Epoxy glue for mini LED and preparation method thereof

Abstract

The invention belongs to the field of epoxy resin, and provides epoxy glue for a mini LED and a preparation method of the epoxy glue. The formula comprises the following components: alicyclic epoxy resin, aromatic epoxy resin, modified epoxy resin, a glyceryl ether diluent, a curing agent, a filler, a flatting agent, a defoaming agent, a coupling agent, a wetting agent and color paste. Through special selection of the resin and the curing agent, the viscosity is reduced, and the fluidity is improved; the expansion coefficient is reduced by adding a physical filler; finally, color paste is added, and the chromaticity is improved to achieve ink color consistency through a dispersion process such as rolling; and good comprehensive quality is obtained. The prepared glue has low viscosity, is easy to level and defoam during molding and curing, and can be used for filling tiny gaps; the processing and the use are convenient. The epoxy resin glue is a single-component epoxy resin glue, is convenient to use and has low requirements on packaging equipment.

Description

technical field [0001] The invention belongs to the field of epoxy resins, and in particular relates to an epoxy glue for miniLED and a preparation method thereof. Background technique [0002] The miniLED display package has traditional SMT and new COB packaging technology. The main differences between the two packages are: [0003] 1. The difference in technology, SMT package is to encapsulate the chip in the bracket, bond it to the PCB board by welding, weld the LED leads through the welding process, and then pour the epoxy resin to form a display module according to a certain distance; COB packaging is a new type of LED packaging technology, which directly solders the light-emitting chip to the PCB without brackets and reflow soldering; [0004] Second, the difference in dot pitch, the traditional SMT package LED screen is P1.5 and larger, the larger the dot pitch, the lower the resolution, subject to the display of the SMT packaging technology itself, it is difficult t...

AI Technical Summary

Problems solved by technology

[0007] 1. The fluidity of the glue is insufficient. At present, the miniLED chips packaged in COB are small, such as 4*8, 3*6, etc., coupled with high integration and small dot spacing, higher requirements are put forward for the fluidity of the glue. The viscosity and thixotropy of the glue are difficult to completely fill the chip gap

[0008] Second, the thermal expansion coefficient of the glue is large and the curing shrinkage rate is large. Excessive shrinkage during the curing process will cause the entire display module board to warp, which will not be flat and affect the subsequent multi-screen assembly. Humidity changes, the glue stress is too large, and then damage the LED chip, reduce the display effect, or even dead light

[0009] Third, the ink color consistency is difficult to guarantee. The mini LED screen is spliced ​​and assembled through dozens or even hundreds of modules. Due to the differences in the color of its own PCB bottom plate and the reflection of the bottom of the chip, it is difficult to pass the current environment. Oxygen glue to achieve ink color consistency

[0010] CN104804694A discloses a novel epoxy resin LED encapsulation glue and its preparation method, but the encapsulation glue is composed of A and B glues and cannot be used directly

Among them, the ultraviolet light absorber needs to be synthesized by itself, which is not easy to obtain. At the same time, when the packaging material is used to encapsulate LED components, matching molds are required, and the equipment used for packaging requires complex requirements.

[0011] CN112375524A discloses an epoxy glue and its preparation method and application. The epoxy glue film prepared by the invention has good heat resistance and high transparency, but the viscosity of the glue is relatively high, basically 8000mPa.s Left and right, not easy to level and defoam during molding and curing

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