Analysis of the Problems in the Gluing Box Process and Solutions

With the rapid development of society and economy, people are increasingly demanding product packaging. Various types of exquisitely-advanced carton boxes are emerging in an endless stream. The traditional hand-glued boxes have not kept pace with the development of the times. Many domestic packaging and printing companies have invested in them. Automatically paste the box equipment, with a view to occupying this market that has not yet been systematically developed as soon as possible.

In the automatic gluing process, various process problems and mechanical malfunctions plague many packaging and printing manufacturers. To this end, we tracked some manufacturers who are using folder gluers, and based on advanced design concepts combined with actual conditions during the production and use of the company, summarized some views and experiences on the faults that occurred during the various parts of the automatic gluing process. , for your reference only.

First of all, we must do a good job in the pre-press design and paste box matching process: pre-press, printing, post-press negotiations of various processes to ensure production quality and improve production efficiency play a crucial role. The matching of the gluing process with the previous process and prepress design is no exception.

The relationship between pre-press design and post-press processing is very close. This requires designers to understand the needs of printing and post-press processing. In recent years, various packaging and printing companies and advertising design companies have found that the profits of packaging printing are higher than those of general books and publications. Therefore, they have swarmed and turned to packaging printing. However, it is not easy to do well in packaging and printing. As far as the final process of gluing boxes is concerned, the quality of gluing boxes is closely linked with the quality of die-cutting. Die-cutting is not good, and the indentation is not deep enough. No matter how good the gluing device is, it is not possible to paste good products. Die-cutting in the die-cutting process is inextricably linked to the pre-press box design. The cardboard of the same specification, due to the different box design, the box is often not the same, so the box design directly affects the quality of the final product.

In this regard, some customers are also deeply impressed. They think that many design companies currently lack understanding of the process flow of packaging and printing production. According to the customer's introduction, once the company took a single job and found that the electronic files produced by the design company could not be used for automated production, not only affecting the production efficiency, but also failed to achieve the designed packaging effect. In this regard, the company's prepress process engineers again proposed changes to the box design, adapted to the automatic production of the folder gluer.

It can be seen that when designing a box type, it is necessary to comprehensively consider the subsequent production process. The box type design must pay attention to the key elements such as folding position, folding angle, size and position of the gluing box, and ensuring that these elements meet the gluing machine. The design accuracy and processing requirements. Only in this way can we match the prepress design with the automatic gluing process.

In the pasting process, everyone encountered a variety of problems. At the same time, various solutions have emerged. Here are some of the problems and the causes of the problems:

1 paste fastness is not high, carton degumming

Degumming refers to peeling off due to insufficient fastness. The main reasons are summarized as follows:

1 The viscosity of the adhesive is not enough or the amount of glue is insufficient;

2Adhesive and carton materials are not suitable;

3 If the sticky part of the carton is subjected to surface treatment such as film coating and glossing, the adhesive is difficult to penetrate the paper through the surface layer, and such a paper box is difficult to be firmly attached;

4 The pressure after the gluing is insufficient and the pressing time is not long enough, which is not conducive to strong paste.

For the above problems caused by adhesives, the adhesives should be selected in accordance with the carton material to be pasted. The selection and use of adhesives are also very particular about.

First of all, one cannot mistakenly believe that the higher the viscosity of the adhesive, the better the sticking effect. With high viscosity, the strength of the adhesive also becomes higher and the wrinkling rate also increases. The recommended viscosity of the adhesive is 500 cps-1000 cps in the case of the automatic gluing machine's gluing roller operating at a high speed of 112 rpm.
Second, the adhesive has a stronger bond. Because the instantaneous pressure in the forming section is not very large, and the high-speed operation of producing 30 to 40 cartons per minute, the pressing dwell time is not long. Adhesives with strong adhesive strength can be firmly bonded even if they are pressed lightly.

Finally, operating the shop's ambient temperature will have a certain impact on the adhesive. If the temperature of the operation shop is too low, the adhesive will immediately solidify, affecting the firmness of the bond. Even if the amount of glue applied is too large, it will not work. Of course, the less the amount of glue applied is, the more sensitive it is to the room temperature. Therefore, in winter, the operating room temperature should be kept as high as 20°C or more, and air conditioners can be used to adjust conditions. In the operation shop, large-scale and easy-to-read thermometers are also installed to check and control the working environment at any time. For a good paste product, it should be dried at room temperature and then leave the factory. In winter, avoid dripping and rushing delivery.

For the carton coated and glazing, the following four methods are available to solve the problem that the gluing chamber is not firm:

1 When the die is cut, a needle knife is placed on the sticky mouth to break the surface of the sticky mouth, which is beneficial to the penetration of the adhesive;

2 Use the edge grinding device attached to the automatic folder gluer to grind the surface of the sticky mouth to facilitate the penetration of the adhesive;

3 The hot melt glue is sprayed on the sticky part, and the material at the high temperature is used to melt the sticky surface to increase the firmness of the paste box;

4 In the design of the pre-press box type, it is possible to leave a glue application area on the edge of the film sheet to be covered and coated in advance.

For the inadequacy of the gluing chamber due to insufficient pressure, the pressure of the gluing section of the gluing machine can be increased, the pressing time can be prolonged, or the adhesive with strong adhesive force can be replaced.

2 carton deformation

There are three main reasons for the deformation of the paper box:

1 Some die-cut versions are hand-made, often due to inconsistent results, resulting in inconsistent cartons, and distorted cases.

2 The adhesive has a low concentration and a large amount of moisture, resulting in moisture absorption and deformation of the paperboard. The carton is not evenly formed after molding:

3 The folder-gluer itself is not adjusted well.

To solve this problem, as long as the stability of the die-cutting quality is ensured, proper adhesives can be selected and the folder-gluer can be adjusted.

3 carton sticky skew

There are mainly three kinds of causes for skewed cartons:

1 Indentation steel wire pressure groove is too wide, indentation pressure is not enough, so that the indentation line is not full, folding can not accurately press the mark line folding;

2 improper adjustment of the folding transmission, the conveyance speed of the left and right sides of the box is inconsistent, resulting in a sticky mouth;

3 The folding bar is not installed properly.

Solution: Reduce the width of the indentation line and increase the indentation pressure; adjust the folding transmission so that the conveyance speeds of the left and right sides of the carton are the same, and re-install the folding bar.

4 sticky mouth is not allowed

The misalignment of the sticky mouth means that the sticky mouth is misaligned and the misplaced carton cannot be well formed. This phenomenon is usually caused by inaccurate tuning accuracy. Further, it is mainly due to the lack of understanding of the box type and folder gluer by the operator, which affects the operation level. Therefore, strengthening the training of operating personnel, upgrading their operating skills and their understanding of complex box types will effectively avoid the problem of inadvertent sticking.
5. Sticky mouth overflow glue

Excess glue refers to excess adhesive out of the sticky mouth. This phenomenon is mainly caused by the misalignment of the gluing chamber and the excessive amount of the adhesive. The occurrence of the glue-out phenomenon can be effectively reduced by grinding the adhesive and reducing the amount of glue.