Technical requirements for gravure printing of the

Technical requirements for intaglio printing of beer labels

at present, China's beer labels mostly use 65-80g/m2 coated paper, wet strength paper and aluminum spray paper to meet social needs. The printing methods are offset printing and intaglio printing. The label quality is related to the fiber direction, flatness, moisture content, dimensional stability, crimping time and other factors of the label paper. The specific requirements are that the fiber direction of the paper is perpendicular to the axial direction of the bottle body; The water content is about 5% - 7%; Under the condition that the cooperation between wet and ISRO Mars Orbiter is also known as 40% - 80%, the single label remains flat; The curling height of the front and back sides shall not be greater than 3mm; The time for the back to curl into a barrel when encountering water shall be greater than 8 seconds. In addition to the above elements, the printing quality should meet the requirements of the wine label, otherwise it will bring difficulties to the labeling

quality problems and reasons that are easy to appear in beer label labeling

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

2. The sheet is dropped during bid winning. The main reason is that the curl height on the front of beer label paper is greater than 3mm, and the air cannot enter between the bid and the label during the labeling process. When taking the label, there are two or more labels

3. The label is pleated or cocked (it is good when sticking the bottle, but the four corners of the label are cocked during the transmission). The main reason is that the moisture content of label paper is low, and it will elongate rapidly in case of water

at present, the technical level of most printing plants can meet the appearance requirements of beer labels. How to control the internal quality of beer labels and meet the labeling requirements is the key point of the process. From the above analysis, it can be seen that the main reason for the problems of beer label curling and warping angle is the low moisture content of beer label paper. If the printing method is different from the post press processing method, it is also necessary to control the printing quality by controlling the moisture change of beer label paper

the change of water content of beer label paper in different printing methods

1. offset labels are printed by single sheet, monochrome or multiple overprinting, and the ink drying is mostly natural conjunctival solidification. Due to the water ink balance in offset printing, the water content of label paper is basically the same as that of printed matter

2. Gravure labels are completed by pre drying, continuous multi-color overprinting and winding of web paper. After each color printing, the ink is dried by drying and solvent volatilization, and the labels will lose water after drying for many times. It can be seen from the moisture @b power supply voltage elongation and drying shrinkage of the paper that offset labels are printed under the condition of "elongation" of the paper, while gravure labels are printed under the condition of "shrinkage" of the paper. Therefore, if the processes of gravure printing beer labels are not well mastered, the finished products will curl due to humidity, resulting in labeling failure. How to solve the problem of water content change in gravure beer labels to meet the requirements of wine bottle labeling? You may wish to pay attention to the following points

precautions for gravure printed beer labels

1. Rewetting: after printing, take out the sample, inspect and record the fracture morphology of the sample, and then restore the water content of the label paper

2. setting: adjust the amount of water replenishment during the rewetting process according to different paper properties

3. Flattening: the single sheet finished product after web cutting should be flattened

4. Maintain the air humidity in the production workshop