Research On Numerical Simulation And Quality Optimization Of Variable Two-dimensional Code Jet Printing Of Cigarette Label

Cigarette labels with variable two-dimensional codes are gradually becoming the mainstream form of cigarette packaging due to their advantages in anti-counterfeiting,traceability,publicity and marketing.With the continuous expansion of coding scale in printing enterprises,the defects of unstable production quality and unguaranteed printing precision are becoming more and more prominent.In response to this problem,this article is based on the overall jet printing process of the variable two-dimensional code for cigarette labels in printing companies.Firstly,the numerical simulation of the variable two-dimensional code jet printing process and the analysis of the ink droplet morphology are carried out;Secondly,the influence of the process parameters of jet printing code on the symbol level of two-dimensional code was studied.Finally,an experimental research on the jet printing quality optimization of the variable two-dimensional code on cigarette labels was carried out.This thesis aims to further improve the printing process of the variable two-dimensional code on cigarette labels,and provide a favorable reference for the actual code printing business on cigarette labels.The main research contents are as follows:1.research on the numerical simulation of jet printing process and the the analysis of the ink droplet morphology.According to the basic principle of piezoelectric ink-jet and the physical properties of the ink,the jet printing process was numerically simulated,and the movement patterns of the ink droplet at different stages were analyzed.By changing the parameters of ink surface tension,viscosity,density and the initial velocity of the ink drop,the influence of the above factors on the motion pattern of the ink drop was discussed.2.Research on the influence of jet printing process parameters on the symbol level of two-dimensional code.The main process parameters(nozzles temperature,nozzles voltage,nozzles distance,paper moving speed)that affect the quality of jet printing were analyzed.The results of actual coding and numerical simulation under different nozzle temperature and nozzle voltage process parameters are compared and discussed,and the relationship between droplet motion pattern and its fixation state was analyzed.Through orthogonal experiment,the influence significance of four process parameters on the seven indicators of the impact evaluation of the symbol level of two-dimensional code was analyzed.It is concluded that the four process parameters have the most significant influence on the two indicators of the fixed pattern damage and the unused error correction of the two-dimensional code.Finally,through the response curves of the two indexes,the optimal combination of process parameters was obtained: nozzle temperature 47?,nozzle voltage 14 V,nozzle distance 0.2mm,paper moving speed 70m/s.3.Research on quality optimization of variable two-dimensional code jet printing.Four types of variable two-dimensional code printing processes were experimented and tested for white cardboard substrate and silver cardboard substrate.By comparing the basal surface properties of the substrate(surface topography,whiteness,gloss,smoothness,absorbency),code quality(two-dimensional code level,ink layer thickness,friction factor,ink layer abrasion resistance)and safety quality of the four processes,the conclusion was drawn: for cigarette label products with white cardboard substrate,the substrate directly printed with the varnish layer has good inkjet adaptability,high coding quality and qualified safety;for the cigarette label products of silver cardboard substrate,the substrate that prints the white ink layer and then the varnish layer has good inkjet adaptability,high coding quality and qualified safety.