High-reliability and high-efficiency fluorescent glass for packaging LED (light emitting diode) and preparation method thereof

Abstract

A high-reliability and high-efficiency fluorescent glass for packaging LED (light emitting diode) and a preparation method of the fluorescent glass, belonging to the field of LED packaging technology. Super-white glass is used as a substrate to be coated with the fluorescent glass powder slurry, and is subjected to heat treatment for curing and sintering, wherein the heat treatment conditions are as follow: the heat treatment is carried out in air atmosphere, heat treatment temperature is 350-600 DEG C, and heat treatment time is 20-150minutes. The components and mass ration of the slurry are as follow: 8-20 parts of fluorescent powder with granularity of 15-50mum, 30-70 parts of low melting point glass powder, 5-20 parts of terpineol, 2-12 parts of non aqueous acrylic resin, and 3-4 parts of cyclohexane. The method is used for LED packaging, the water vapor transmission rate is lower than 10-4g / m<2>.24h, the luminous efficiency of white light LED is 141lm / W, the LED is not affected by the effect of ultraviolet radiation aging, and the method facilitates industrial production, simplifies LED packaging process, reduces packaging cost and improving service life.

Description

technical field [0001] The invention belongs to the technical field of LED packaging, and relates to a fluorescent glass for LED packaging with high reliability and high efficiency and a preparation method thereof. Background technique [0002] LED solid-state lighting is an inevitable trend of future development. The lumen efficiency of LED has exceeded 200lm / W, the lumen efficiency of ordinary fluorescent lamps is 85lm / W, and the lumen efficiency of incandescent lamps is 15lm / W. Therefore, LEDs will definitely decrease with the cost And the improvement of efficiency and enter the field of general lighting. The theoretical life of LED is 100,000 hours, but it is generally only about 10,000 hours at present. The main reason is the aging and failure of packaging materials. [0003] In the prior art, the LED packaging material uses silica gel mixed with phosphor powder, and then coated on the surface of the LED chip. The phosphor powder and silica gel must be mixed evenly in ...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, the LED packaging material uses silica gel mixed with phosphor powder, and then coated on the surface of the LED chip. The phosphor powder and silica gel must be mixed evenly in advance, which requires the particle size of the phosphor powder to be small (less than 15 μm) and consistent. Good performance, at the same time, it is necessary to add light scattering agent to improve the uniformity of light, otherwise it will lead to uneven sedimentation of phosphor powder, resulting in uneven light output and light leakage of LED. The disadvantage is that the water vapor transmission rate of silica gel is greater than 30g / m 2 24h, silica gel is susceptible to aging by ultraviolet rays and heat, which leads to accelerated aging of packaging materials, which in turn affects the luminous efficiency and service life of the entire LED

On the other hand, since the luminous efficiency of phosphor is proportional to the size of phosphor particles, the size of the encapsulated particles is less than 15 μm, which limits the luminous efficiency of LED. At the same time, the mixing dispersion of phosphor and silica gel is not easy to control during the preparation process. Moreover, the coating process of phosphor powder must be strictly controlled, so the preparation is difficult

Images