How to meet the labeling requirements of beer label gravure printing

At present, most of China's beer labels use 65-80g/m2 single-sided coated paper, wet strength paper, and aluminum spray paper. The printing methods are offset printing, gravure printing, and the label quality and label fiber orientation, flatness, moisture content, and size. Stability, curling time and other factors. The specific requirement is that the paper fiber direction is perpendicular to the bottle body axial direction; the water content is about 5% to 7%; under the condition of humidity of 40% to 80%, the single label remains flat; the front and back surface curl height is not more than 3mm; The time for the back of the water to curl into a tube should be greater than 8 seconds. In addition to the above elements, the printing quality must meet the requirements of the wine label, otherwise it will bring difficulties to the labeling.

The Probable Quality Problems and Causes in Beer Labeling

1. The glue is uneven (there are glues on the upper and lower sides, no glue in the middle or glue in the middle and glue on the left and right sides). The main reason is that the beer label paper is uneven and the positive and negative curl heights are more than 3mm.

2. Lost Zhang when taking the bid. The main reason is that the front curl height of the beer label paper is greater than 3mm, and air cannot enter between the label and the label during the labeling process. When the label is taken, the label appears double or multiple sheets.

3. The label is pleated or curled (very good when bottled, but the label is curled at the corners during transport). The main reason is that the moisture content of the label paper is low and the water rapidly expands.

At present, the technical level of most printing factories can meet the appearance requirements of beer labels. How to control the intrinsic quality of beer labels and meet the labeling requirements is a key process. From the above analysis, it can be seen that the main cause of problems such as curling and curling of beer labels is that the moisture content of beer labels is low. If the printing method is different from the post-press processing method, the printing quality needs to be controlled by controlling the moisture change of the beer label paper.

Change of Water Content of Beer Label Paper in Different Printing Methods

1. Offset labels are printed single-sheet, single-color or multiple-overprint. The ink drying is mostly cured by the natural conjunctiva. Because there is water-ink balance in the offset printing, the water content of the label paper is basically the same as the water content of the printed matter.

2. The gravure label is web pre-dried, continuous multicolor overprint. After the winding is completed, the ink is dried after each color printing and the solvent is volatilized and dried. After the label is dried many times, it will cause water loss. From the moisture-elongation and drying shrinkage of the paper, it is known that the offset label is printed with the paper "stretched" and the gravure label is printed with the paper "shrinking". Therefore, if the processes for gravure beer labeling are not well mastered, the finished product will suffer from curling due to humidity, resulting in labeling failures. How to solve the problem of changing the moisture content of the gravure beer label to meet the bottle labeling requirements? May wish to pay attention to the following points.

Gravure beer label considerations

1. Rewetting: Restore the moisture content of the label after printing;

2. Stereotype: adjust the amount of water in the rewetting process according to different paper properties;

3. Leveling: The finished sheet after cutting the web should be flattened;

4. Keep the air humidity in the production workshop.


Source: Shenzhen Printing Network