What is the reason for the inconsistency in printing color depth and "run version"?
The main reason is that the ink viscosity is poorly controlled; the ink transfer state is unstable; the paper feeding state is unstable. The poor flatness of paperboard is also an important reason.
Therefore, to maintain the consistent color and layout accuracy of corrugated board ink printing, the following must be done:
1. Keep the ink viscosity stable.
The ink viscosity is the main indicator that needs to be controlled in the printing of corrugated cardboard. It is one of the main factors that affect the printing color condition. Since the ink solvent volatilizes during the printing process, the base viscosity increases, and in order to maintain the stability of the ink viscosity, the ink stabilizer should be added every 0.5-1 hour, and the amount added is 1%-2%.
2. Keep the amount of ink transferred stable.
For this reason, it is necessary to maintain a balanced and stable printing speed. Because the speed of printing is related to the state of ink transfer, it must be run in a balanced manner and cannot be ignored. Balanced paper should also be maintained, and paper feeds cannot be separated. Only in this way can the ink printing machine have a stable ink transfer state, which has an important role in maintaining the stability of the printing ink color.
3. Keep the paper feed stable.
In addition to the stable operation speed of the printing press, the manual feed point should be fixed. For poorly flat cardboard, it should be properly handled, such as folding along one side (or both sides) of the cardboard transverse pressure line; hand pressure feeding, etc. All guide gaps should be consistent. These are related to keeping the cardboard stable The important link is also an important way to "run version" of the phenomenon.
4. To keep the printing equipment in good condition.
The emphasis here is to keep the anilox roll and printing plate clean, clean and directly related to the printing effect. The anilox roller is related to the ink transfer performance, and the printing plate is related to the print text and the clarity of the pattern.
Three printing process <br> <br> printed corrugated box development in the country have for decades, from the earliest hand-engraved flexographic printing some simple product information, to today's laser flexographic printing, offset printing with a difference With a small, exquisite pattern, we can easily see that with the development of the market economy and the integration of the international environment, corrugated carton packaging has increased the basic functions of placing goods and protecting goods in the transportation process, adding promotional products, Promote sales and other functions, play a certain container effect. To achieve the promotion of products and promote sales, the effect of printing is of course exquisite. Maybe some people will say that if they want to be beautiful, then use offset printing to print. Let us analyze the advantages and disadvantages of several types of printing.
Corrugated box printing is currently divided into two printing methods, one is offset printing, the other is ink printing.
Offset printing is familiar to most people. It is printed on sheet-fed paperboard first, then the printed paperboard and corrugated cardboard are faced to each other, and finally die-cut. Offset printing in the printing process is more difficult to control the hue of different batches of production, so the color difference problem is the technical problem of each offset printing plant; because the offset printing is transferred by more than a dozen transfer rollers, it is also known as the long ink road. . Each transfer roller needs to adjust the pressure to transfer the ink. No one operator can adjust the pressure between the rollers to ensure that the pressure adjusted at each or the same time is the same. This will make Color differences occur in the same product in different batches.
The printed cardboard and the corrugated board are placed side by side and placed one or two days afterwards, so that the glue can be dried and then dried and then the cutting work can be done; thus, the processing time will be longer. In the process of offset printing, due to insufficient pressure on the corrugated medium and excessive moisture left in the glue, it is difficult for the technical indexes such as the compressive strength, bursting resistance, and adhesiveness of the finished product box to meet the requirements of some products for packaging. , such as beer boxes, I do not know if everyone has noticed, when we buy the whole box of beer to take home, you will find some cardboard boxes in his hand feel soft, like to be broken; while some cardboard boxes held in Feeling quite stiff in the hand. You can understand that most of the software is offset.
Therefore, offset printing requires thicker paper to enhance the strength of the carton. Domestic domestic breweries have done such data surveys. The same box, if you want to achieve a certain pressure resistance index, offset printing should use more than 180 grams of cardboard to achieve, and flexo face paper only 150 grams of cardboard to achieve the technical indicators.
There are two types of ink-and-ink printing. One is the direct printing of the corrugated boxes (post-printing), and the other is the pre-printing.
Ink printing is transmitted through an anilox roller. The anilox roller is quantitative. Under the premise of constant ink, the same color. If the same anilox roller is used, the hue printed by different batches is basically the same.
Ink printers are generally slotted and can be die-cut directly after printing. The printed carton is an unfolded carton. From the production efficiency faster than offset printing.
Because the corrugated cardboard is composed of a face paper, a core paper and a liner paper, and has a hollow structure, corrugated paperboards inevitably generate a washboard phenomenon due to different forces during the printing process.
Of course, the direct printing technology of corrugated boxes is also constantly improving.
