Research On The Preparation Of Silver Nanoparticles And Their Application In Laser Etching Paste

In recent years the smartphone market is developing rapidly,people are becoming more and more like ultra-thin mobile phones.Now people’s attention begins to focus on the pursuit of ultra-narrow border,the border width has become one of the key factors which influence the visual effect.Ultra-narrow border has strict requirements on silver nanoparticles size and performance.We dried the laser-etched silver paste after printing,and then laser-etched to obtain ultra-narrow lines.If we want to implement this process,it needs that silver nanoparticles have good compatibility with laser etching paste.So we focused on how to prepare the silver nanoparticles of consistent with the laser etching process,and the properties of silver nanoparticles in laser etching paste after sintering.In this paper,we used the chemical reduction method to prepare silver nanoparticles.We investigated the effect of the preparation parameters of silver nanoparticles,including the concentration of silver nitrate,ascorbic acid,disodium edetate,sodium citrate and the polyvinylpyrrol idone,PH value and so on.The result showed that when the concentration of silver nitrate was 0.2 mol/L,the size of silver nanoparticles was in about 100 nm,and there were no special big particles.By changing the single variable,when the molar ratio o f ascorbic acid and silver nitrate was 2,hydrated sodium citrate and silver nitrate was 0.1,polyvinylpyrrolidone and silver nitrate quality percentage was 2%,the PH value was 1,silver nanoparticles were the most conform to the requirements of the laser etching.Under the condition of laboratory,we perfored different magnification experiments,when magnified 100 times,the monodispersity of silver powder got worse.In this thesis,we studied the separation method of silver nanoparticles in the solution,and found that the use of recycled water type multipurpose vacuum pump was highest efficiency,natural precipitation was the lowest cost and add starch flocculant was suitable under the condition of high temperature.Separately we studied the ethanol,eth yl acetate and acetic acid as cleaning agent of silver nanoparticles,the results indicated that acetic acid as cleaning agent,the mass-to-volume ratio of silver nanoparticles and acetic acid was 4%,ultrasonic treatment for 20 minutes,the sheet resista nce of silver nanoparticles was the lowest in the laser etching paste.In this thesis,we found that when the sintering time was 60 minutes,cast powder was 75%,and mixed grinding time was 40 minutes,the silver powder could have a good compatibility with laser etching paste and showed a low resistance.