Preparation Of Screen Printable Catalytic Activated Ink And Its Application Research

The traditional micro-graphic methods of electronic circuits/devices are based on the "etching-subtraction method",which is a complex process,long production cycle,high material waste,high production costs and poor environmental compatibility,making it difficult to achieve further breakthroughs in large-area manufacturing and ultra-low-cost manufacturing of electronic products."All Printed Electronics"（APE）technology is an electronic circuit/device fabrication method developed in recent years,which uses the "additive method" as the primary graphic process route.Compared with the cumbersome preparation process,high preparation costs and serious material wastage,and etching pollution of the "subtractive method",all-printed-electronics technology shows great promise as a large-area,flexible,low-cost,and green additive technology.In this work,based on screen printing technology,a thermosetting screen-printable ink system with catalytic activity was developed to print graphically active functional layer on rigid/flexible substrates with surface pre-treatment and combining with the electroless copper plating process to prepare graphically metallic conductive layer.The specific contents of the research are as follows:（1）A thermosetting screen printing ink formulation structure with polyurethane resin as the ink body,dibasic ester（DBE）solvent as the dilute solution,and silver nitrate as the catalytically active source donor.Using sec-butylamine and silane coupling agent KH560 as the carrier for adsorbing silver,two kinds of screen-printable thermosetting inks with catalytic activity were prepared after component optimization.These inks are simple in composition,environmentally friendly,conform to screen-printing viscosities and print adaptability,and the storage performance of the inks were investigated,the storage time can reach 45 days.（2）For two typical rigid/flexible substrates such as PET substrate and glass fiber resin plate,the influence of pretreatment methods such as oxidizing micro-roughening solution and plasma corona treatment on the adhesion of metal conductive layer was studied.The results showed that the best adhesion performance can be achieved with a specific concentration of alkaline potassium permanganate micro-roughening solution and an output power of 240 W corona intensity.The influence law of screen printing mesh on the fineness of printed graphic was studied,and the optimal curing temperature was determined based on the differential scanning thermal analysis results of the ink and the high-temperature resistance conditions of the substrate,and the influence law of different curing times on the adhesion performance of the prepared metallic copper layer was analyzed.The results showed that the ink system has the best graphic accuracy when the screen mesh is 420,the ink layer can be completely cured at a low temperature of 160 ℃for 5 minutes.（3）The effect of different chemical deposition times on the resistivity,film thickness and morphology of copper metal layers in the electroless copper plating solution system with formaldehyde as reducing agent was studied.The results showed that when the deposition time was 20 min,the resistivity of the copper layer prepared by the secbutylamine complex Ag catalytic active ink was 2.19 μΩ·cm,which is 1.28 times of the pure copper,and the adhesion performance met the highest adhesion 5B standard of ASTM D3359-02.the resistivity of the copper layer prepared by the coupling agent grafts Ag catalytic active ink was 2.31 μΩ·cm,which is 1.35 times that of pure copper,and the adhesion performance also met the 5B standard.