It can be seen from the relevant national standards of barcodes and the quality indicators of barcode printing that commodity barcodes are not a simple set of patterns, and the printing quality of commodity barcodes is quite particular. In order to print qualified barcode quality, it is very important to adopt scientific and perfect printing quality control.
1. Self-adhesive barcode design
The design of commodity barcodes should start with the predictability of its indicators, such as barcode uniqueness, barcode color matching, blank area width, barcode height, magnification, optical characteristics, and printing position. Fully consider all indicators in line with national standards, while taking into account the beautiful packaging and decoration.
2. Print media and media
Commonly used packaging materials, such as plain paper, cardboard, plastic film, aluminum foil, tinplate, corrugated cardboard and some special printing materials, can be used as the printing carrier of self-adhesive commodity barcodes. However, it should be noted that when choosing a printing carrier, it is necessary to avoid using those narrow-width reflective materials, and try not to use transparent, translucent and poor coloring materials. If these materials are required for packaging and decoration, the part where the product barcode is printed should be surface-treated.
In order to ensure the printing accuracy of commodity barcodes, printing materials with good dimensional stability, moderate ink diffusion, low permeability, and good flatness and finish should be selected. For rougher corrugated cardboard and woven bags, self-adhesive barcode labels can be used. When printing barcodes on tinplate and aluminum foil, full consideration should be given to their high temperature resistance.
When printing commodity barcodes, the ink that matches the carrier should be selected, and attention should be paid to the uniformity and diffusion of the ink. Poor ink uniformity can lead to oil seepage or insufficient ink consumption, blurred edges of printed graphics, blemishes, and bar code symbol spacing that is out of tolerance. When using specular reflective material or transparent material as barcode carrier, two inks that absorb completely different should be selected.
3. Commodity barcode film
When ordering or making product barcode film, please consider and check the following for consistency: product barcode type (EAN-13 or EAN-8), identification code on the film, bar reduction, positive or negative, top or bottom membrane. Which film to choose should depend on the needs of plate making and process. Usually, the production of letterpress and letterpress uses negative film, and the production of gravure, gravure and stencil uses positive film. Direct printing (except stencil) selects the film on the top, direct printing with stencil and indirect printing select the film on the bottom.
4. Printing adaptability experiment
The so-called printing suitability experiment is to verify the suitability of the various elements of the printing conditions (the sum of the equipment, carrier, ink, process, environment, etc. for printing commodity barcodes), and determine the bar width compensation of the barcode. Barcode film and barcode symbol computer graphics files. Experiments are based on design parameters such as quantity. The suitability test must be carried out in strict accordance with GB/T18805-2002 "Commodity Barcode Printing Suitability Test". The printing conditions for the barcode printability test should be the same as the printing conditions for the official barcode printing.
5. Printing method
According to the form of plate making, printing methods can be divided into letterpress printing, offset printing, gravure printing and stencil printing. The characteristics of the printing method and the practice have proved that the product bar code of lithographic and gravure printing has good quality stability and high dimensional accuracy, and is suitable for printing product bar codes of different magnifications. It is the best choice for printing product barcodes. Traditional letterpress printing has poor stability and large dispersion of dimensional errors, so it is not suitable for printing commodity barcodes. If letterpress printing must be used for product packaging and decoration, in order to ensure the quality of product barcodes, it is recommended to use offset printing product barcodes first, and then use letterpress to print other decorations. Stencil printing can be used to print commodity barcodes at medium magnifications.
6. Printing Inspection
The printing quality inspection of commodity barcode symbols is an important link to ensure the quality of commodity barcodes. Commodity barcodes should be checked for printing quality before trial printing and before the finished product leaves the factory. The inspection should be carried out in strict accordance with GB/T18348-2001 "Commodity Barcode Symbol Printing Quality Inspection".
