From the relevant national standards of barcodes and barcode printing quality indicators, it can be seen that commodity barcodes are not a set of simple patterns, and the printing quality of commodity barcodes is quite particular. If you want to print qualified product barcode quality, it is very important to adopt scientific and perfect printing quality control.

1. Design of product barcode

The design of commodity bar codes should be based on the predictability of their indicators, such as the uniqueness of the code, the color matching of the bar, the width of the blank area, the height of the bar, the magnification factor, the optical characteristics, and the printing position. Fully consider that every index meets the national standards, while taking into account the beauty of packaging and decoration.

2, print carrier and media

Commonly used packaging materials, such as ordinary paper, cardboard, plastic film, aluminum foil, tinplate, corrugated paper plate and some special printing materials can be used as the printing carrier of commodity bar codes. But it should be noted that when choosing a printing carrier, avoid using those narrow reflective materials, and try not to use transparent, translucent and poorly colored materials. If these materials are required for packaging and decoration, surface treatment should be carried out on the part where the barcode of the product is printed.

In order to ensure the printing accuracy of commodity barcodes, printing materials with good dimensional stability, moderate ink diffusion, low permeability, smoothness and smoothness should be selected. For rougher corrugated paper plates and woven bags, self-adhesive bar code labels can be used. When printing bar codes on tinplate and aluminum foil, full consideration should be given to their high temperature resistance.

When printing commodity barcodes, you should choose the ink that matches the carrier, and pay attention to the uniformity and spread of the ink. Poor ink uniformity will cause oil leakage or insufficient ink consumption, blur the edges of the printed graphics, stains, and make the bar code symbol size out of tolerance. If using specular reflective material or transparent material as the barcode carrier, two inks with completely different absorbency should be used.

3, commodity barcode film

When ordering or making a product barcode film, the consistency of the following should be considered and checked: the product barcode type (EAN-13 or EAN-8), the identification code on the film, the reduction in bar width, positive or negative film, and the Up or down. The choice of film depends on the needs of plate making and process. Normally, negative films are used for letterpress and planographic printing, and positive films are used for intaglio plates and stencils. For direct printing (except for stencils), choose the medicinal film on the top, and use the stencil for direct printing and indirect printing to choose the medicinal film on the bottom.

4. Printing suitability 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 bar codes, and to determine the bar width compensation of the bar code film and the bar code symbol computer graphic file And other design parameters. The suitability test must be strictly carried out in accordance with GB/T18805-2002 "Commodity Barcode Printing Suitability Test". The printing conditions of the barcode printing suitability experiment should be the same as the printing conditions of the formal 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 practice have proved that the product barcodes printed by offset printing and gravure printing have good quality stability, high dimensional accuracy, suitable for printing product barcodes with different magnification factors, and are the best choice for printing product barcodes. Traditional letterpress printing has poor stability and large dimensional error dispersion, which is not suitable for printing commodity barcodes. If the packaging and decoration of the product must be printed with letterpress, in order to ensure the quality of the product barcode, it is recommended to print the product barcode with lithography first, and then use letterpress to print other decorations. The stencil printing can be used to print commodity barcodes with a mid-range magnification factor.

6. Printing quality inspection

Commodity barcode symbol printing quality inspection is an important process to ensure the quality of commodity barcodes. Commodity barcodes should undergo a printing quality inspection before trial printing and finished products leave the factory. The inspection shall be carried out in strict accordance with GB/T18348-2001 "Quality Inspection of Commodity Barcode Symbol Printing".