Fabrication Of Flexible Conductive Circuits Based On Screen Printing And In-situ Volume Addition

The development of electronic information technology has made conductive' circuits highlight important status.Traditional photolithographic process are cumbersome,polluting and material wasting As the environmental issues are increasingly prominent today.Therefore,it is urgent to develop a simple,environmental friendly and effective method for the conductive circuit preparation.This study uses screen printing patterning combined with in-situ volumetric addition technology to propose a simple and effective conductive circuit fabrication method.This subject prepared copper-containing photo-curable ink firstly,Then patterned the copper nanoparticles with screen printing method.Finally,the copper nanoparticle pattern converted into a conductive silver pattern by in-situ volumetric addition,and relized conductive fuction.Firstly,according to the performance requirements,this study choose appropriate light-curing resin.The oligomer is CN120NS,diluent is TPGDA,the mass ratio between oligomers and active diluents is 6:4,photo-initiator is TPO-L,the mass of photo-initiator is 1%of the resin.The changes in properties before and after the addition of the copper nanoparticles were studied,such as flexibility,adhesion,and viscosity of the resin.Finally a suitable ink formulation was determined.Then use screen printing to prepare the PET-based copper nanoparticle pattern,and to find the reason why it cannot conduct:there are gaps between the copper particles.The conductive network is discontinuous.According to the principle of metal in-situ volume addition,silver nanoparticles were used to replace copper nanoparticles in situ to prepare silver patterns,and the patterns were electrically conductive.The SEM,EDS,and XRD methods were used to determine the electrical conductivity:The generated metal particles increased in both number and volume.In addition,silver grows in dendritic or lamellar crystallineforms.The growth characteristics of the morphologies makes it easier for metals to contact each other to form a continuous conductive structure.The factors such as oxygen inhibition,ink viscosity,content of copper,photocuring times,concentration of silver nitrate solution,and reaction times were studied.The.optimum experimental conditions were determined as follows:First,a photocurable ink pattern having a copper content of 70 wt%was light-cured for 30s,then soak the pattern in a 0.1 mol/L silver nitrate solution for 30 minutes,and the resulting silver pattern was light-cured in a nitrogen atmosphere for 15 minutes.During the pross,mercury lamp is used as the light source,and the light intensity was 60 mW/cm2.The resulting conductive line conductivity was 1.25 X 105 S/m.Finally,study the properties of bending,fatigue,and repairable and prepared flexible circuits.