Methods of fabricating quantum dot color film substrates

Patent metadata

Field	Value
Publication number	US-10120232-B2
Application number	US-201615023691-A
Country	US
Kind code	B2
Filing date	Jan 29, 2016
Priority date	Dec 8, 2015
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

The present application provides a method of fabricating a quantum dot color film substrate, red and green quantum dots are respectively formulating into red and green quantum dot inks, then formation is performed by an inkjet printing, and a color filter layer is obtained, thereby brightness and color saturation of displays can be increased; simultaneously, the red quantum dot ink and the green quantum dot ink at least have an ink of epoxy resin system therein, when the ink of epoxy resin system is yet cured, a graphene conductive layer is formed thereon to act as an electrode, so that a greatly improved adhesion of the graphene conductive layer and the color filter layer can be obtained. Additionally, to replace ITO by utilizing graphene as a conductive layer can alleviate current issues of few ITO sources and increasing price, and the graphene has conductivity and high transmittance that make display quality of TFT-LCD screen be guaranteed, and an overall thinned and lightened panel be achieved. Such design helps increasing conductivity and integrating benefits, and also has very great application prospect in curved panel market.

First claim

What is claimed is:

1. A method of fabricating a quantum dot color film substrate, comprising following steps:
step 1, providing a transparent substrate;
partitioning the transparent substrate into side by side arranged red pixel regions, green pixel regions and transparent pixel regions;
step 2, forming a patterned organic transparent photoresist layer corresponding to the transparent pixel regions on the transparent substrate;
step 3, providing a red quantum dot ink and a green quantum dot ink; the red quantum dot ink and the green quantum dot ink at least having an ink of epoxy resin system therein, the ink of epoxy resin system having a prescription as follows:
an epoxy resin of 40-65 wt %;
a curing agent of 1-15 wt %;
an accelerating agent of 0.3-8 wt %;
a diluting agent of 10-20 wt %;
pigments of 3-12 wt %;
quantum dots of 1-10 wt %;
coating the red quantum dot ink corresponding to the red pixel regions on the transparent substrate by way of inkjet printing, to form a patterned red quantum dot layer, coating the green quantum dot ink corresponding to the green pixel regions on the transparent substrate by way of inkjet printing, to form a patterned green quantum dot layer, so as to obtain a color filter layer comprising the organic transparent photoresist layer, the red quantum dot layer and the green quantum dot layer;
step 4, forming a graphene conductive layer on the color filter layer when the ink of epoxy resin system is yet cured, to increase adhesion of the graphene conductive layer and the color filter layer; then, completely curing the ink of epoxy resin system on the transparent substrate by one or two ways of UV curing and thermosetting;
step 5, forming a black photoresist layer on the graphene conductive layer, the black photoresist layer comprising a black matrix, and main spacers and auxiliary spacers located on the black matrix.

2. The method of fabricating the quantum dot color film substrate according to claim 1 , wherein the red quantum dot ink and the green quantum dot ink have viscosities in 1-40 cp, and surface tensions in 30-70 dy/cm.

3. The method of fabricating the quantum dot color film substrate according to claim 1 , wherein, in the ink of epoxy resin system, the epoxy resin is a bisphenol A epoxy resin;
the curing agent is hexahydrophthalic anhydride, tetrahydrophthalic anhydride, butanedihydrazide, adipic dihydrazide, dicyanodiamide or p-phenylenediamine;
the accelerating agent is 2-ethyl-4-methylimidazole, imidazole, dimethylimidazole or triethylamine;
the diluting agent is one of isopropyl alcohol, acetone, n-butyl alcohol, glycol ether, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol methyl ether acetate, propylene glycol monomethyl ether acetate, or a combination thereof;
the pigments are one of red, green and yellow pigments, or a combination thereof according to display requirement, the red, green and yellow pigments respectively are one of monoazo yellow and orange pigment, disazo pigment, naphthol series pigment, azo lake based pigment, azo condensation pigment, benzimidazolone pigment, phthalocyanine pigment, thioindigo pigment, quinacridone based pigment, quinophthalone based pigment, anthraquinone pigment, dioxazine pigment, triarylmethane based pigment, and diketopyrrolo pyrrole based pigment, or a combination thereof;
the quantum dots corresponding to red and green quantum dot inks respectively are quantum dots of emitting red light and green light, a material of the quantum dots comprises one or more than one of II-VI groups quantum dot material, and one or more than one of I-III-VI groups quantum dot material; structures of the quantum dots are spherical, core-shell type, spheroidal with convex, or irregular shape.

4. The method of fabricating the quantum dot color film substrate according to claim 1 , wherein, in step 4, the graphene conductive layer is formed by using transfer, inkjet orienting, spray coating, slit coating, or spin coating.

5. The method of fabricating the quantum dot color film substrate according to claim 1 , wherein, on the transparent substrate, the red pixel regions and the green pixel regions are spaced by the transparent pixel regions, each the red pixel region is located between two of the transparent pixel regions, each the green pixel region is located between two of the transparent pixel regions; in step 3, with the organic transparent photoresist layer as a barrier wall, coating the red and green quantum dot inks corresponding to the red and green pixel regions on the transparent substrate by the way of inkjet printing.

6. The method of fabricating the quantum dot color film substrate according to claim 5 , wherein, in step 3, for preventing overflow, coating thicknesses of the red quantum dot layer and the green quantum dot layer are set as 0.01-2 μm less than a thickness of the organic transparent photoresist layer;
in step 5, the black matrix comprises longitudinal light shading bands and lateral light shading bands; the main spacers are disposed corresponding to the organic transparent photoresist layer above the lateral light shading bands, and the auxiliary spacers are disposed corresponding to the red quantum dot layer and the green quantum dot layer above the lateral light shading bands.

7. The method of fabricating the quantum dot color film substrate according to claim 5 , wherein a ratio of an area of the transparent pixel regions (AT) to an area of the red pixel regions (AR) is in a range of 0.05≤AT/AR≤0.5, a ratio of the area of the red pixel regions (AR) to an area of the green pixel regions (AG) is in a range of 0.3≤AR/AG≤1.

8. The method of fabricating the quantum dot color film substrate according to claim 1 , wherein, in step 2, a material of the organic transparent photoresist layer is a transparent photoresist material having UV curable, thermosetting, or simultaneously photo curable and thermosetting performance; the organic transparent layer is obtained through a yellow light lithography.

9. A method of fabricating a quantum dot color film substrate, comprising following steps:
step 1, providing a transparent substrate;
partitioning the transparent substrate into side by side arranged red pixel regions, green pixel regions and transparent pixel regions;
step 2, forming a patterned organic transparent photoresist layer corresponding to the transparent pixel regions on the transparent substrate;
step 3, providing a red quantum dot ink and a green quantum dot ink; the red quantum dot ink and the green quantum dot ink at least having an ink of epoxy resin system therein, the ink of epoxy resin system having a prescription as follows:
an epoxy resin of 40-65 wt %;
a curing agent of 1-15 wt %;
an accelerating agent of 0.3-8 wt %;
a diluting agent of 10-20 wt %;
pigments of 3-12 wt %;
quantum dots of 1-10 wt %;
coating the red quantum dot ink corresponding to the red pixel regions on the transparent substrate by way of inkjet printing, to form a patterned red quantum dot layer, coating the green quantum dot ink corresponding to the green pixel regions on the transparent substrate by way of inkjet printing, to form a patterned green quantum dot layer, so as to obtain a color filter layer comprising the organic transparent photoresist layer, the red quantum dot layer and the green quantum dot layer;
step 4, forming a graphene conductive layer on the color filter layer when the ink of epoxy resin system is yet cured, to increase adhesion of the graphene conductive layer and the color filter layer; then, completely curing the ink of epoxy resin system on the transparent substrate by one or two ways of UV curing and thermo

Assignees

• Shenzhen China Star Optoelect

Inventors

• Zhang Xia

Classifications

• G02F1/133516 Primary

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• G02F1/1335

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• H01J2329/326

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• C01B32/186

  by chemical vapour deposition [CVD] · CPC title