To ensure the stability of the color of the copper plate label paper, you can start from the following aspects:
First, establish a reasonable color management system
1.Formulate color standards: When producing a label product for the first time, the upper limit, standard and lower limit of the color of the label product should be formulated, and it is determined as "proof" after customer confirmation. In the future production, the standard color of the sample is based on it, and the fluctuation of the color can not exceed the upper and lower limits.
2.Strengthen inspection and random inspection: Strengthen inspection and random inspection in the printing and production process of label products in order to timely discover and deal with label products that exceed the reasonable range of color difference.
Second, the use of printing standard lighting source
Many label printing companies do not use printing standard lighting sources, which causes hidden dangers for the color consistency control of label products. Therefore, it is recommended to use the printed standard lighting source for lighting, and conditional enterprises also need to be equipped with a standard light source box in order to allow employees to contrast the color of label products under the standard light source. This can effectively avoid the problem of print color difference caused by non-standard lighting sources.
Third, pay attention to the choice and use of ink
1.Use of ink produced by regular manufacturers: the use of expired ink can easily lead to fading of label products, etc., so you should choose ink produced by regular manufacturers, pay attention to the shelf life of ink, and update the inventory in time.
2.Control the amount of ink additives used: Excessive use of ink additives may also lead to changes in the color of the ink after printing.
3.Standardized ink preparation: The first preparation of spot color ink should be recorded by the operator's ink ratio on the process card, in order to provide the data basis for the next preparation of the spot color ink, while ensuring the consistency of the color of different shifts and different operators.
Fourth, precise control of printing parameters
1.Dot density and size: The dot density and size on the plate need to be equivalent to the dot density and size on the sample to avoid color differences.
2.Roller parameters: The color of flexo label products is also affected by the number of network cables and the depth of mesh holes of the roller. Under normal circumstances, the ratio of the number of lines added to the roller and the number of lines added to the plate is 3:1 or 4:1. Once these parameters are determined, the color of similar labels will be basically the same for each batch produced in the future.
3.Printing pressure: The printing pressure should be appropriate, too large or too small may affect the printing effect.
4.Ink viscosity: Adjust the viscosity of the ink according to the printing speed and graphic category to ensure the printing quality.
Fifth, pay attention to the impact of paper characteristics on printing
1.Paper smoothness: Paper surface smoothness is closely related to imprinting replication. Uneven paper often requires greater pressure to make the ink have good contact with it. Such as ink viscosity, fluidity, ink layer thickness to maintain a certain amount, increasing pressure often increase the printing spread area.
2.Paper absorption: The absorption of paper affects the penetration of ink and the saturation of imprinting. The paper with low absorption can make most of the ink film appear on the surface of the paper, so that the imprinted ink layer has a better saturation.
Sixth, the use of color management system
The color management system running in the color desktop system can improve the stability of the printing quality through output, printing, proofing, and thus improve the accuracy of the output color. On the one hand, color management is to control and standardize the output device, establish the feature file, that is, the target feature file, so that it can be integrated into the color management system.
Seventh, regular calibration and maintenance of equipment
1.Periodically calibrate the display: For devices that perform screen soft proofing, the display should be periodically calibrated to meet the standards for graphic art reproduction.
2.Maintenance of printing equipment: Regular maintenance and maintenance of printing equipment to ensure that it is in the best working condition to avoid printing color differences caused by equipment problems.
In summary, to ensure the stability of color label paper color needs to start from many aspects, including the establishment of a reasonable color management system, the use of printing standard lighting sources, pay attention to the selection and use of ink, accurate control of printing parameters, pay attention to the impact of paper characteristics on printing, the use of color management systems and regular calibration and maintenance of equipment.