Reasons for Excessive Opening of Color Box after Forming paper box

Reasons for Excessive Opening of Color Box after Forming paper box

The packaging color box of the product should not only have bright colors and generous design pastry box , but also require the paper box to be beautifully formed, square and upright, with clear and smooth indentation lines, and without exploding lines. However, some thorny issues often arise during the production process, such as the phenomenon of the opening part being too large after some packaging boxes are formed, which directly affects consumers’ trust in the product.

The packaging color box of the product should not only have bright colors and generous design, but also require the paper box to be beautifully formed, square and upright, with clear and smooth indentation lines, and without exploding lines. However, some thorny issues often arise during the production process, such as the phenomenon of opening the opening area too large after some packaging boxes are formed. The same is true for pharmaceutical packaging boxes, which face millions of patients. The poor quality of packaging boxes directly affects consumers’ trust in the product. At the same time, the large quantity and small specifications of pharmaceutical packaging boxes make it more difficult to solve the problem. Based on my practical work experience, I am now discussing with my colleagues the issue of excessive opening after forming pharmaceutical packaging boxes.

There are various reasons for the excessive opening of the paper box after forming, and the decisive factors are mainly in two aspects:

1、 the reasons on the paper, including the use of web paper, the water content of the paper, and the fiber direction of the paper.

2、 Technological reasons include surface treatment, template production, depth of indentation lines, and assembly format. If these two major problems can be effectively solved, then the problem of paper box forming will also be solved accordingly.

1、 Paper is the main factor affecting the formation of paper boxes.

As you all know, most of them now use drum paper, and some still use imported drum paper. Due to site and transportation issues, it is required to cut the paper domestically. The storage time of the cut paper is short, and some manufacturers have difficulty in cash flow, so they sell and buy it now. Therefore, most of the cut paper is not completely flat and still has a tendency to curl. If you directly purchase sliced flat paper, the situation is much better, at least it has a certain storage process after cutting. In addition, the moisture contained in the paper must be evenly distributed, and must be phase equilibrium with the surrounding temperature and humidity, otherwise, deformation will occur over a long period of time. If the cut paper is stacked for too long and not used in a timely manner, and the moisture content on the four sides is greater or less than the moisture content in the middle, the paper will bend. Therefore, in the process of using cardboard, it is not advisable to stack it for too long on the day it is cut to avoid causing deformation of the paper. The excessive opening of the paper box after forming also affects the fiber direction of the paper. The horizontal deformation of paper fibers is small, while the vertical deformation is large. Once the opening direction of the paper box is parallel to the fiber direction of the paper, this phenomenon of opening bulging is very obvious. Due to the absorption of moisture during the printing process, the paper undergoes surface treatment such as UV polishing, polishing, and lamination. During the production process, the paper may deform to some extent, and the tension between the surface and bottom of the deformed paper may not be consistent. Once the paper deforms, the two sides of the paper box are already fixed and glued when it is formed, and only when it is opened outward can the phenomenon of excessive opening after forming occur.

2、 The process operation is also a factor that cannot be ignored when the opening of the color box forming is too large.

1. The surface treatment of drug packaging usually adopts processes such as UV polishing, film covering, and polishing. Among them, polishing, film covering, and polishing cause the paper to undergo high-temperature dehydration, significantly reducing its water content. After stretching, some paper fibers become brittle and deformed. Especially for water-based machine coated paper with a weight of 300g or more, the stretching of the paper is more obvious, and the coated product has inward bending phenomenon, which generally needs to be manually corrected. The temperature of the polished product should not be too high, usually controlled below 80 ℃. After polishing, it usually needs to be left for about 24 hours, and the next process production can only proceed after the product is fully cooled, otherwise there may be a line explosion.

2. The production technology of die-cutting plates also affects the formation of paper boxes. The production of manual plates is relatively poor, and the specifications, cutting, and bending knives in various areas are not well grasped. Generally, manufacturers basically eliminate manual plates and choose beer plates made by laser knife mold companies. However, issues such as whether the size of the anti lock and high and low lines is set according to the weight of the paper, whether the specifications of the cutting line are suitable for all paper thicknesses, and whether the depth of the die line is appropriate all affect the effectiveness of the paper box forming. The die line is a mark made on the surface of a paper by the pressure between the template and the machine. If the die line is too deep, the fibers of the paper will deform due to pressure; If the cutting line of the mold is too shallow, the paper fibers will not be fully pressed through. Due to the elasticity of the paper itself, when both sides of the paper box are formed and folded back, the notches on the opening edge will expand outward, forming a phenomenon of excessive opening.

3. To ensure good indentation effect, in addition to selecting suitable indentation lines and high-quality steel knives, attention should also be paid to adjusting machine pressure, selecting adhesive strips, and installing them in a standardized manner. Generally, printing manufacturers use the form of pasting cardboard to adjust the depth of the indentation line. We know that cardboard generally has a loose texture and insufficient hardness, resulting in less full and durable indentation lines. If imported bottom mold materials can be used, the indentation lines will be more full.

4. The main way to solve the fiber orientation of paper is to find a solution from the perspective of composition format. Nowadays, the fiber direction of paper in the market is basically fixed, mostly in the longitudinal direction. However, the printing of color boxes is done by assembling a certain amount onto a single folio, three folio, or four folio paper. Generally, without affecting product quality, the more pieces of paper are assembled, the better. This can reduce material waste and thus reduce costs. However, blindly considering material costs without considering fiber direction, The formed cardboard box cannot meet the customer’s requirements. In general, it is ideal for the fiber direction of paper to be perpendicular to the direction of the opening.

In summary, the phenomenon of excessive opening of the paper box after forming can be easily solved as long as we pay attention to this aspect during the production process and try to avoid it from the aspects of paper and technology.