An ultrathin white covering film and an LED substrate using the white covering film

Abstract

The invention discloses an ultrathin white covering film and an LED substrate using the white covering film, the ultrathin wite covering film comprises a white ink layer and an adhesive layer, whereinthe white ink layer is located on the upper surface of the adhesive layer; the total thickness of both the white ink layer and the adhesive layer is 4 to 50 [mu]m, wherein the thickness of the whiteink lay is 1. 25 [mu]m, and the thickness of the adhesive layer is 3 to 25 [mu]m; The white ink layer comprises a composition of an organic pigment and a white filler, at least one of an inorganic pigment and an organic pigment, the inorganic pigment being a white pigment or a grey pigment, the organic pigment being a highly transparent polymer, and the white filler being at least one of silicon dioxide, titanium dioxide, alumina and alumina. The ultrathin white coating film has extremely low dielectric constant and loss, extremely high ion purity, high reflectivity, high temperature yellowingresistance, low penetration rate, low gloss, high flexibility, low rebound force, high surface hardness and good weather resistance, and is particularly suitable for use in LED lighting with high performance of a soft-hard combined plate.

Description

technical field [0001] The invention belongs to the technical field of cover films for LEDs (light-emitting diodes), in particular to an ultra-thin white cover film and an LED substrate using the white cover film. Background technique [0002] With the development of the information and communication industry driving the rapid development of the microelectronics industry, flexible printed circuit boards (Flexible Printed Circuit, FPC) came into being and developed rapidly. widely used. The biggest difference between a flexible printed circuit board and a PCB (Printed Circuit Board, rigid printed circuit board) is that the function of the former's use of a cover film exceeds that of the solder resist ink used in the PCB. It not only acts as a solder mask, but also protects the FPC from dust, Moisture, chemical erosion, and can reduce the impact of stress in the bending process. In addition, with the development of the FPC market, the cover film has been endowed with more fu...

AI Technical Summary

Problems solved by technology

[0004] The first method: After the cover film is opened, the substrate is pressed, and after low-temperature drying, a layer of white ink A100 is coated on the surface to improve the contrast of LED products and enhance its printing effect. The disadvantage is that the printing thickness is uneven and flexible. Poor flexibility (such as figure 1 );

[0005] The second type: use a white ink cover film directly attached to the FPC substrate, the white ink cover film includes the first white ink layer B100, the yellow PI (polyimide) layer B200, the first adhesive layer B300 and the first Release layer B400, which can reduce the downstream process, but the high temperature yellowing resistance of the white ink cover film is poor, and it is difficult to achieve thinning (such as figure 2 );

[0006] The third method: use a white PI cover film to directly attach to the FPC substrate. The white PI cover film includes a white PI layer C100, a white adhesive layer C200 and a second release layer C300, which has good resistance to high temperature yellowing and weather resistance And has high reflectivity, but its cost is high and thinning is difficult to achieve (such as image 3 )

Images