Fluorescent-powder dispensing glue for white-light SMD nixie tube and application method thereof

Abstract

The invention discloses a fluorescent-powder dispensing glue for a white-light SMD nixie tube and an application method thereof. The glue is prepared from the flowing raw materials: an epoxy resin main agent, an epoxy-resin hardener, a fluorescent powder, a diffusion powder and an anti-sedimentation powder with a mass ratio of (90-110):(90-110):(4-10):(5-11):(1-7). According to the fluorescent-powder dispensing glue for the white-light SMD nixie tube and the application method thereof, the adhesion degree of the glue is improved, the fluorescent powder mixed in epoxy resin is uniformly distributed and enables white light to be emitted uniformly, epoxy resin subjected to baking is relatively substantially improved in hardness compared with silica gel and is capable of protecting luminescent chips and a lead from being damaged by external force or temperature-difference stress; and the dispensing method enables color rendering of the nixie tube to be uniform and helps to substantially save the fluorescent powder.

Description

technical field [0001] The invention relates to a fluorescent powder dispensing glue for a white light patch digital tube and a use method thereof. Background technique [0002] Currently on the market, there are several techniques for digital tubes to display white light: the first is to use white SMD lamp beads to weld them on the PCB, and then press them with the plastic case to achieve. The disadvantage of this process is that the cost is high; the second is The first is to attach a fluorescent film on the surface of the digital tube. The disadvantage is that the fluorescent film cannot withstand high temperatures and cannot withstand the high temperature of reflow soldering when used on SMD products; the third is to mix fluorescent film in the digital tube potting glue. powder to achieve white light, the disadvantage is that the waste of phosphor is more serious; the fourth is the COB process in which silica gel mixed with phosphor is directly dispensed on the wafer, wh...

AI Technical Summary

Problems solved by technology

[0002] Currently on the market, there are several techniques for digital tubes to display white light: the first is to use white SMD lamp beads to weld them on the PCB, and then press them with the plastic case to achieve. The disadvantage of this process is that the cost is high; the second is The first is to attach a fluorescent film on the surface of the digital tube. The disadvantage is that the fluorescent film cannot withstand high temperatures and cannot withstand the high temperature of reflow soldering when used on SMD products; the third is to mix fluorescent film in the digital tube potting glue. powder to achieve white light, the disadvantage is that the waste of phosphor is more serious; the fourth is the COB process in which silica gel mixed with phosphor is directly dispensed on the wafer, which has emerged in the past two years, but the silica gel and potted epoxy resin are due to stress during baking. Different, it will cause the reliability problem of breaking the aluminum wire and causing the dead lamp. For this, our company has developed a new dispensing process to solve the reliability problem. It also has the advantages of low cost, uniform light emission, high temperature resistance, and phosphor saving.

In the domestic market, white light digital tubes are basically assembled using white light SMD chip technology. Most domestic counterparts use the process of pasting fluorescent film on the digital tubes or mixing fluorescent glue as a whole, but the biggest disadvantage of this process is : Uneven color rendering and serious phosphor waste

And traditional dispensing uses silica gel mixed with fluorescent powder with high viscosity to operate, but the viscosity of silica gel mixed phosphor is low, and the phosphor mixed in silica gel is easy to precipitate, so that the white light is uneven