CN-121974570-A - Flexible ultrathin glass cover plate and preparation method thereof

Abstract

The invention provides a flexible ultrathin glass cover plate and a preparation method thereof, wherein the preparation method of the flexible ultrathin glass cover plate comprises the steps of providing ultrathin glass; and carrying out vacuum drying and baking curing treatment on the polyimide resin solution to form a polyimide film, thus obtaining the flexible ultrathin glass cover plate. According to the flexible ultrathin glass cover plate and the preparation method thereof, polyimide organic films with specific compositions are utilized to toughen ultrathin glass, and the foldable flexible ultrathin glass cover plate meeting the requirements of a flexible display screen is prepared.

Inventors

• YANG JINFA
• LI SHULI
• YAN JUANJUAN
• ZHOU ZIHAN
• Wang Xunzi
• Gu an

Assignees

• 凯盛科技股份有限公司

Dates

Publication Date

20260505

Application Date

20251224

Claims (10)

1. 1. The preparation method of the flexible ultrathin glass cover plate is characterized by comprising the following steps of: providing ultra-thin glass; coating polyimide resin solution on one side surface of the ultrathin glass; And carrying out vacuum drying and baking curing treatment on the polyimide resin solution to form a polyimide film, thus obtaining the flexible ultrathin glass cover plate.
2. 2. The method for manufacturing a flexible ultrathin glass cover plate according to claim 1, wherein the ultrathin glass has a thickness of 50-150 μm and a hardness of more than 5H.
3. 3. The method for preparing a flexible ultrathin glass cover plate according to claim 1 or 2, wherein the polyimide resin solution comprises 100 parts by weight of polyamic acid A, 50-80 parts by weight of polyamic acid B and 0-20 parts by weight of additive; The polyamide acid A is prepared by polycondensation of silicon dioxide with surface modified by halogenated alkane silane coupling agent, diamine monomer containing nitrogen heteroaryl and dianhydride monomer, and the polyamide acid B is prepared by polycondensation of aminophenyl cage polysilsesquioxane, diamine monomer and dianhydride monomer.
4. 4. The method for manufacturing a flexible ultrathin glass cover plate according to claim 3, wherein the haloalkane silane coupling agent is at least one of chloromethyltriethoxysilane, 3-chloropropyl dimethoxymethylsilane or 3-chloropropyl methyldimethoxysilane; the diamine monomer containing nitrogen heteroaryl is at least one of 2- (4-aminophenyl) -5-amino-benzimidazole, 2- (3-aminophenyl) -5-amino-benzimidazole, 2, 5-diaminoimidazole, 4' -diamino-bipyridine, 2, 6-diaminopyridine or 3, 5-diaminopyridine; the diamine monomer is at least one of p-phenylenediamine, 4' -diaminodiphenyl ether, 4' -diaminodiphenyl sulfone, 2' -dimethyl-4, 4' -biphenyl diamine or 4,4' -diamine benzoyl benzene, the dianhydride monomer is at least one of benzene dianhydride, 3', 4' -biphenyl tetracarboxylic dianhydride, 4' -oxydiphthalic anhydride or 3,3', 4' -benzophenone tetracarboxylic dianhydride.
5. 5. The method for preparing a flexible ultrathin glass cover plate according to claim 3 or 4, wherein the additive is at least one of a coupling agent, a wetting and leveling agent or a flame retardant; preferably, the coupling agent is a siloxane coupling agent or a titanate coupling agent, the wetting and leveling agent is polyether modified organosiloxane or polyester modified organosiloxane, and the flame retardant is a phosphorus-containing flame retardant.
6. 6. The method for producing a flexible ultrathin glass cover according to any one of claims 1 to 5, wherein the vacuum drying treatment temperature is 80 to 150 ℃ and the time is 0.5 to 2 hours, the baking curing treatment temperature is 200 to 300 ℃, and the film is formed by continuous heating reaction curing.
7. 7. The method for producing a flexible ultrathin glass cover sheet according to any one of claims 1 to 6, wherein the thickness of the polyimide film is 1 to 20 μm.
8. 8. The method for manufacturing a flexible ultrathin glass cover plate according to any one of claims 1 to 7, further comprising attaching a protective film to one side surface of a polyimide film and/or coating an OCR adhesive layer to one side surface of the ultrathin glass far from the polyimide film and attaching a lower protective film; Preferably, the upper protective film or the lower protective film is a PE protective film or a PET protective film, and the thickness is 50-100 mu m.
9. 9. A flexible ultrathin glass cover sheet prepared by the method of any one of claims 1-8.
10. 10. The flexible ultrathin glass cover plate according to claim 9, wherein the flexible ultrathin glass cover plate comprises an upper protective film, a polyimide film, ultrathin glass, an OCR glue layer and a lower protective film which are sequentially laminated from top to bottom.

Description

Flexible ultrathin glass cover plate and preparation method thereof Technical Field The invention belongs to the technical field of display, and particularly relates to a flexible ultrathin glass cover plate and a preparation method thereof. Background In recent years, the rapid development of flexible display technology has driven the commercialization of folding screen devices, and at the same time, higher demands are being made on the comprehensive properties of the cover plate material. Currently, transparent polyimide (CPI) polymer films and ultra-thin glass (UTG) inorganic materials are mainly used, and the two materials are also considered as the most promising and potential materials. But solutions using both materials alone as flexible cover plates have obvious advantages and disadvantages. CPI is used as a polymer material, and has the advantages of excellent bending performance, excellent impact drop resistance and good mass production performance, and has the disadvantages of softer hardness, poorer optical performance, poorer friction resistance (required to be coated with a hardening layer) and more obvious crease compared with UTG. UTG as an inorganic material has the advantages of stronger hardness, excellent optical performance, better scratch resistance, and the disadvantages of poor bending performance, poor impact resistance, fragility and the like. Disclosure of Invention Based on the technical problems mentioned in the background art, the invention provides a flexible ultrathin glass cover plate and a preparation method thereof, and the flexible ultrathin glass cover plate meeting the requirements of a flexible display screen is prepared by toughening ultrathin glass with polyimide organic films with specific compositions. The invention provides a preparation method of a flexible ultrathin glass cover plate, which comprises the following steps: providing ultra-thin glass; coating polyimide resin solution on one side surface of the ultrathin glass; And carrying out vacuum drying and baking curing treatment on the polyimide resin solution to form a polyimide film, thus obtaining the flexible ultrathin glass cover plate. In the invention, the ultrathin glass is taken as a cover plate substrate, the cover plate can be ultrathin and has enough hardness, so that a plurality of defects existing in a pure polymer cover plate are avoided, but the ultrathin glass has certain flexibility and hardness and also brings mechanical properties such as reduction of folding resistance, so that polyimide resin solution is adopted to coat the ultrathin glass, a polyimide organic film is formed on the ultrathin glass, and the polyimide organic film layer has the advantages of high transparency, high hardness and high strength, and has the advantages that the high transparency is beneficial to displaying and protecting the ultrathin glass from bursting after being applied to the surface of the ultrathin glass as a high polymer material, and the folding resistance is improved under the condition similar to the hardness of the glass. Preferably, the thickness of the ultrathin glass is 50-150 mu m, and the hardness is more than 5H. Preferably, the polyimide resin solution comprises 100 parts by weight of polyamic acid A, 50-80 parts by weight of polyamic acid B and 0-20 parts by weight of additive; Wherein, the polyamide acid A is prepared by polycondensation of silicon dioxide with surface modified by halogenated alkane silane coupling agent, diamine monomer containing nitrogen heteroaryl and dianhydride monomer, and the polyamide acid B is prepared by polycondensation of aminophenyl cage polysilsesquioxane, diamine monomer and dianhydride monomer. In the invention, although polyimide resin has certain flexibility and is favorable for improving the flexibility of the glass cover plate, the polyimide resin is used as an outer layer material of the glass cover plate, but has the problem of insufficient hardness, after the silicon dioxide modified by the halogenated alkane silane coupling agent is adopted for polycondensation with a diamine monomer containing nitrogen heteroaryl and a dianhydride monomer, the halogenated alkane contained in the silicon dioxide modified by the halogenated alkane silane coupling agent can undergo quaternization reaction with the nitrogen heteroaryl in the diamine monomer containing nitrogen heteroaryl, so that the silicon dioxide is grafted on the diamine monomer, and then the silicon dioxide can be chemically grafted on the obtained polyimide molecular chain after the silicon dioxide is subjected to polycondensation with the dianhydride monomer, thus the flexibility of the coating is ensured, and meanwhile, the hardness of the coating is improved, and on the other hand, the cationic group formed by the quaternization reaction can weaken or inhibit the effect of a charge transfer complex, so that the optical transparency of the polyimide film is improved, and meanwhile, the bonding