Affect corrugated carton printing problem solution

1. What are the main printing methods for paper packaging products?

The printing methods of paper packaging products mainly include letterpress printing (including flexographic printing). screen printing. Offset offset and gravure etc. Different packaging products need to select different printing methods according to the printing materials and the different requirements for product quality.

2. What are the main advantages of packaging products produced by offset printing?

Packaging products produced by offset printing have a fine pattern. Bright ink, clear graphics and other advantages. Compared with letterpress printing and screen printing, offset printing enables a more realistic reproduction of tones and colors of color originals; offset printing has a shorter plate-making cycle than gravure printing. The advantages of low plate making costs. In particular, the rapid development of prepress technology in recent years. The development of offset press towards high speed and multicolor, the rapid development of China's manufacturing industry and the improvement of customer's requirements for product packaging quality have made offset printing one of the main packaging and printing methods.

3. What are the limitations of producing packaging products by offset printing?

The thickness of the offset ink layer is not as thick as the gravure printing and the screen printing, so the ink color is not as thick as the gravure printing and the silk screen printing. Offset machines have strict requirements on the shape and material quality of substrates. For example, offset printing pressure is too large to directly print corrugated cardboard. Offset printing machines have certain restrictions on the thickness of substrates, and they cannot print thick paperboards.

4. How to produce corrugated boxes/boxes by offset printing?

Traditional corrugated cartons/boxes are too thick and too soft to be printed directly by an offset press. Therefore, a single sheet or cardboard must be printed by offset printing. After processing with glazing, peritoneum, etc., the corrugated cardboard must be processed. Die cutting, paste boxes and other processing.
With the appearance of thin corrugated cardboard, some well-known overseas offset printing equipment manufacturers have jointly tackled problems with rubber blankets and ink suppliers, which have enabled E-Watt, F-Watt, and G-Watt to achieve direct printing of offset presses, but need special blankets. There is also a high demand for equipment. Not all offset machines are competent.

5. How to produce cardboard cartons by offset printing?

Different offset presses allow different thicknesses of substrates to be printed, but they all have certain limitations, and more than this range cannot be printed. If the desired carton thickness exceeds this range, you must first print the thinner cardboard and then add one or more layers of paperboard.

6. What kind of offset press is suitable for producing packaging cartons?

A sheet-fed offset press is suitable for the production of packaging cartons, and the allowable range of substrate thickness is better. Because there is often a large area on the packaging printing. The more pronounced ink bars tend to appear in the printing, so the offset press should have better manufacturing accuracy and a longer ink path. Usually, the printing ink layer in the field is relatively thick, and the back stains are likely to occur. It is preferable to have facilities for preventing back rubbing, such as powder spraying devices and auxiliary drying devices.

7. In the selection of packaging materials should pay attention to what issues?

1 The materials used for the blanks and the visual effects of the ink layer cover should be compatible with the packaged materials. The material of the material can protect the fragile contents, the structural strength can withstand the weight of the items, and should have better sanitation. Performance, do not pollute the loaded items;

2 The materials selected meet the requirements of economic efficiency and environmental protection;

3 The materials used should be able to meet the performance requirements of the offset press on the substrate, and have good offset printing suitability.

8. From the point of view of the offset printing process, what problems should be noted when designing packaging cartons?

1 If the width of the packaging carton exceeds the width of the printing press, the carton should be divided into two halves for printing.

2 If the thickness of the packaged product exceeds the thickness range of the offset printing machine, thin cardboard should be printed first, and then one or more layers of cardboard should be laid on it;

3 In addition to aesthetic considerations, the design of the pattern must also take into account the ease of reproduction of the printing process and the effect of copying.

The number of times of 4 printing should consider the beauty of the pattern at the same time. Economic benefits. The number of printing presses and the overlay accuracy of the machine.

9. When using color prints as originals, what issues need attention?

The use of color prints as originals is only used in special cases where the original manuscript for producing the color prints does not exist, because the color prints have been copied once, resulting in the loss of part of the layers. 2. The copy again must be more deviating from the color of the first manuscript. Tones and sharpness; In addition, the color print itself is an image formed by the interlacing of the dots, and after the color separation and screening, an unattractive moiré is easily generated, which affects the copy quality. Therefore, when such an original is used, measures should be taken to prevent the occurrence of moiré in the prepress production. For the over-molded packaging prints as originals, due to creases on the original, corresponding measures must be taken to deal with the crease marks. For the bleeding part that has been die-cut, measures should be taken to make up, or the enlarged image of the original document should be enlarged to give the bleeding site.

10. What is an outlet or field?

Dots are the most basic units for the representation of tonality and color of an image in a printed image, which is equivalent to many centers. For small dots with the same density and unequal area, offset printing uses the dot area in the unit area to express the level. Regardless of the 90:6 position or the 30% position, the center-to-center distance and density between every two mesh points are equal. Only the percentage of the image area of ​​the image per unit area is 90% and 30%, respectively. If the substrate surface of the graphic part is completely covered with ink, which is equivalent to 100% of the dot, it is called the field.

Reprinted from: print128.com