Printing process of self-adhesive label paper--Printing self-adhesive labels

Modern label printers are mostly multipurpose. Users can change the processing technology according to their needs. All kinds of wear-resistant self-adhesive labels, different materials use different production processes, general barcode labels are processed by the following processes.

There are two ways to print barcodes.

One is the commercial production of barcode labels using batch printing and copy printing equipment, which usually overlays barcodes and patterns.

The second is computer-controlled real-time printing of barcode labels and barcode files. The former is suitable for barcodes with a large number, fixed features and the same content, and is also designed and printed synchronously with the external graphics and text on the packaging. The latter can be computer controlled to provide instant printing with a high degree of flexibility as needed. Barcode printers include inkjet printers, thermal printers, thermal transfer printers, impact matrix printers, and laser printers. In order to ensure that the printed barcode meets the specification requirements, the plate making process should be considered according to the printing process and the characteristics of the substrate. For example, in a flexographic printing process, the line width can be appropriately reduced during the platemaking process to compensate for the increased printing variation. When printing on shrink packaging materials, the position of the barcode after the film is shrunk needs to be considered during plate making, and the longitudinal and transverse shrinkage coefficients are pre-calculated for adjustment. For the convenience of normal reading during use, attention should be paid to the matching of barcode colors.

In the barcode reading system, the light source of the scanner is usually a red light source with a wavelength of 630-700nm, so the red light effect of the ink color should be considered. The incident light of the scanner falls on the barcode surface of different materials and colors, and the reflection effect is also different. Black ink can completely absorb red light, and the reflectivity of printed matter to incident light is usually below 3%, so most barcode designs are printed with black ink. White ink fully reflects red light, and the reflectivity of its prints to incident light is close to 100%, making it an ideal pure color. For the above reasons, barcodes on printed products are usually printed on white paper.

However, some packaging products, starting from the decorative effect, will also choose other color combinations, so we must pay attention to matching according to the nature of the color. Generally, the colors with high red light reflectivity are yellow, orange, red, light brown, etc. While black, green, purple, blue, etc., red light reflectivity is low. Reasonable barcode printing color design must fully consider factors such as the color reflectivity of red light. Transparent film packaging should not be directly printed with barcodes. It should be printed with white ink or yellow, orange and red as the substrate first, and then printed with dark barcodes such as black, dark green, dark blue, etc., making it easy to read and use.