Fluorescent powder coating liquid of white light emitting diode as well as preparation method and coating method thereof

Abstract

The invention provides a method for configuring a fluorescent powder coating liquid of a white light emitting diode. The fluorescent powder coating liquid of the white light emitting diode includes the fluorescent powder and a binder, wherein the binder is an inorganic compound nanometer silica sol, and the inorganic compound nanometer silica sol and the fluorescent powder have weight percentage ratios of 60-85% and 40-15%. The method includes: slowly pouring the silica sol into a ball mill with 15%-40% of fluorescent powder, then adding ball mill balls with diameters of phi6, phi10, phi15 and a weight ratio of 2:1:1 for mixing and milling. The fluorescent powder coating liquid has the advantages that the membrane enveloping effect on the fluorescent powder is realized by utilizing the nano silica sol; the damage of the harmful ultraviolet radiation on the fluorescent powder is reduced; and the hot quenching property of the fluorescent powder is lowered so that the attenuation of the fluorescent powder and the color bleaching of the light emitting diode are reduced, and the aging resistance property of the light emitting diode is improved.

Description

technical field [0001] The invention relates to the technical field of packaging of white light emitting diodes, in particular to a white light emitting diode fluorescent powder coating solution and a preparation method and coating method thereof. Background technique [0002] Light-emitting diodes (LEDs) have the advantages of high efficiency, energy saving, and environmental protection. The technological progress of white LEDs has created conditions for LEDs to enter the field of general lighting. LEDs are generally considered by the industry to be the main lighting source in the 21st century. Technically, the realization of white light LED mainly includes: use RGB (red, green, blue) three primary colors multiple chips or multiple devices to emit light and mix them into white; apply RGB phosphor powder on the ultraviolet light chip, and use purple light to excite the phosphor powder Produce three-primary color mixing to form white light, or coat YAG (yttrium aluminum garn...

AI Technical Summary

Problems solved by technology

[0005] The above-mentioned traditional phosphor coating methods are prone to the following problems: 1. Organic colloids (such as epoxy and silicone) cannot effectively protect against ultraviolet radiation, resulting in damage to the phosphor, such as aging attenuation, color drift, etc.

The literature "Research on Phosphor Powder Aging in White LED" (Foshan Institute of Science and Technology (Natural Science Edition), 2007, 25(4), 6-8) analyzed and confirmed that the attenuation of the conversion rate of phosphor powder under thermal effect and current effect is One of the important factors affecting the aging of white light LED; patent CN201062757Y (Zhu Jianping) is to change the phosphor layer to the lens so as to increase the distance between the phosphor layer and the chip to avoid the attenuation and aging of the phosphor; 2. During the coating process, rapid sedimentation is caused by the large density difference between the phosphor powder and the organic colloid, and the process needs to constantly stir the mixed liquid of the phosphor powder and the glue solution to alleviate this tendency; 3. During the use of the LED, the non-crystalline organic polymer Thermal motion in the form of rotation, movement and orientation of the chain segment relative to other parts of the molecule will lead to further migration, sedimentation or agglomeration of the phosphor, resulting in the drift of the LED color