An electronic screen chemical thinning process and apparatus

Abstract

The application discloses an electronic screen chemical thinning process and device, characterized in that the process comprises the following steps: S1, performing full-closed UV film protection on a non-thinning area of the electronic screen and performing plasma surface activation on a thinning area; S2, performing gradient grading dynamic spray etching on the thinning area by using a high-activity etching liquid and a low-activity corrosion etching liquid to complete glass substrate thinning; S3, synchronously performing online dynamic deslagging by ultrasonic oscillation and inert micro-bubbles during the etching process; S4, removing residual etching liquid and impurities by multi-stage countercurrent washing; and S5, performing UV debonding and film removing after drying to complete thinning. The electronic screen chemical thinning process and device can consider high-precision thinning, all-around screen protection, no residue and adapt to special-shaped screens, and have strong practicability and good application prospect.

Description

Technical Field

[0001] This invention belongs to the field of screen processing technology, and more specifically, relates to a chemical thinning process and apparatus for electronic screens. Background Technology

[0002] With the rapid development of smartphones, tablets, wearable devices, and automotive display terminals towards thinner, more flexible, and higher-definition designs, thinning the screen glass substrate has become a key process for achieving ultra-thin portability, flexible bending, and high light transmittance in terminal devices. Chemical thinning, with its advantages of high processing efficiency, good surface flatness, and adaptability to complex screen structures, has become the mainstream technology for electronic screen thinning.

[0003] However, existing chemical thinning technologies for electronic screens still suffer from several insurmountable technical drawbacks: poor etching uniformity, traditional chemical thinning uses a single mixed acid etching solution, resulting in uncontrollable etching rates and defects such as over-etching, pitting, and wavy unevenness on the glass substrate surface, making it difficult to guarantee thickness uniformity and severely affecting screen display quality and light transmittance. Research shows that under a single acid etching system, the retention of reaction products on the glass surface leads to local concentration differences, which is the main cause of uneven etching; and precision structures are easily corroded. Electronic screens contain precision structures such as circuits, IC chips, and COF flexible cables. During chemical thinning, the etching solution can easily seep into non-processed areas along microscopic capillary gaps, causing circuit corrosion, chip failure, and a significant reduction in screen yield. Existing protective coating methods are mostly simple film application, which makes it difficult to achieve zero-gap bonding in irregularly shaped areas; reaction residue removal is difficult, and the reaction residue generated during the etching process adheres to the glass surface and cannot be removed in time, forming local etching blind spots, resulting in uneven thinning thickness, making subsequent cleaning difficult and easily leaving stains; conventional immersion and spray thinning processes are difficult to adapt to the uniform thinning requirements of irregularly shaped and curved screens, with large deviations in thinning thickness between the edge and center areas, and ultra-thin glass is prone to breakage and warping during the thinning process.

[0004] Currently, the industry lacks a chemical thinning technology that can simultaneously achieve high-precision thinning, all-round screen protection, no residue, and compatibility with irregularly shaped screens, which seriously restricts the mass production and quality improvement of high-end electronic screens. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problems existing in the chemical thinning of electronic screens and to provide a chemical thinning process and device for electronic screens that can achieve high-precision thinning, all-round screen protection, no residue residue and adaptability to irregularly shaped screens.

[0006] To achieve the above objectives, the technical solution adopted by this invention is as follows: The provided electronic screen chemical thinning process includes the following steps: S1, applying a fully enclosed UV coating to the non-thinning area of ​​the electronic screen and performing plasma surface activation on the thinning area; S2, using a high-activity etching solution and a low-activity etching inhibitor to perform gradient-level dynamic spray etching to complete the glass substrate thinning; S3, simultaneously performing online dynamic slag removal through ultrasonic vibration and inert microbubbles during the etching process; S4, using multi-stage countercurrent cleaning to remove residual chemicals and impurities; S5, performing UV debonding and film removal after drying to complete the thinning.

[0007] The protective film used in the fully enclosed UV coating protection in step S1 includes a polyimide or polyethylene terephthalate substrate layer and a UV photosensitive curable adhesive layer. The curing light intensity is 500-1500 mJ / cm², the porosity of the cured film layer is ≤0.5%, and the breakdown voltage is ≥15kV / mm.

[0008] The treatment gas for plasma surface activation in step S1 is oxygen or an argon-oxygen mixture, with a power of 200-500W and a treatment time of 30-120s.

[0009] The high-activity etching solution in step S2 consists of the following components by mass fraction: 15%-22% hydrofluoric acid, 8%-15% sulfuric acid, 1%-3% corrosion inhibitor, 0.5%-1.5% surfactant, and the balance of deionized water; the low-activity corrosion-inhibiting etching solution consists of the following components by mass fraction: 8%-12% hydrofluoric acid, 5%-10% nitric acid, 2%-4% corrosion inhibitor, 0.8%-2% chelating agent, and the balance of deionized water; the corrosion inhibitor is a compound of benzotriazole and organophosphate, with a compounding mass ratio of 1:1 to 3:1.

[0010] The gradient-level dynamic spray etching described in step S2 includes a first-stage coarse etching and a second-stage fine etching: the etching temperature is 25-40℃, the coarse etching time is 3-8 min, removing 70%-85% of the thickness of the glass substrate; the fine etching time is 5-12 min; the spray pressure for both stages of etching is 0.2-0.5 MPa.

[0011] The frequency of the ultrasonic oscillation in step S3 is 28-40KHz, the flow rate of the inert microbubbles is 0.5-1.2L / min, and the inert gas is nitrogen or argon.

[0012] The multi-stage countercurrent cleaning in step S4 includes a first-stage acid washing, a second-stage pure water washing, and a third-stage ultrapure water washing. The cleaning temperature is 30-45℃, and the cleaning time for each stage is 2-5 minutes. A countercurrent circulation water supply method is used.

[0013] The drying process in step S5 is a combination of hot air drying and nitrogen blowing, with a drying temperature of 50-70℃ and a drying time of 3-8 minutes; the UV gelling process involves a light intensity of 2000-4000 mJ / cm² and an irradiation time of 30-90 seconds.

[0014] An electronic screen chemical thinning device for implementing the aforementioned process includes a frame, a feeding and conveying module, a fully enclosed protection module, a gradient etching module, a dynamic slag removal module, a multi-stage cleaning module, a drying and demolding module, a waste liquid recovery module, and a central control module.

[0015] The feeding and conveying module adopts a belt conveyor line and is equipped with a vacuum adsorption fixture that is compatible with flat screens, curved screens and irregularly shaped screens.

[0016] The fully enclosed protective module is sequentially equipped with a plasma activation unit, a UV coating unit, and a curing unit along the transmission direction.

[0017] The gradient etching module is a sealed, constant temperature, and dust-free chamber structure, with a built-in dual-path independent chemical spraying system, temperature sensor, laser + infrared dual-mode online fully automatic thickness detection unit, chemical parameter real-time monitoring unit, and adaptive control unit, realizing independent storage, supply, and automatic switching of the two gradient etching solutions.

[0018] The dynamic slag removal module integrates an inert gas supply unit and an ultrasonic vibration unit, and is integrated with the gradient etching module.

[0019] The multi-stage cleaning module is divided into three independent cleaning chambers and adopts a counter-current water supply system.

[0020] The drying and decoction module includes a hot air drying unit, a nitrogen blowing unit, and a UV degumming unit.

[0021] The waste liquid recovery module connects the gradient etching module and the multi-stage cleaning module, and has a built-in filtration unit and purification unit to realize the recycling of waste liquid.

[0022] The dual-mode online fully automatic thickness detection unit has a detection accuracy of 0.1μm; the real-time chemical solution parameter monitoring unit can detect the concentration, pH value, temperature and flow rate of the etching solution in real time, and automatically complete the chemical solution replenishment and parameter calibration; the waste liquid recovery module has a filtration accuracy of ≤1μm and an etching solution recycling rate of ≥85%.

[0023] Compared with existing technologies, this invention has the following advantages: It provides a chemical thinning process and apparatus for electronic screens, achieving precise control of thinning thickness and significant improvement in surface quality through gradient etching technology; it completely eliminates the erosion of non-processed areas such as screen circuits and chips by the etching solution at the physical level through fully enclosed UV curing coating protection technology; it promptly removes reaction residues and eliminates local etching blind spots through online dynamic slag removal technology; it reduces thinning stress and prevents ultra-thin glass from shattering and warping through low-temperature temperature control and corrosion-inhibiting formula; and it achieves green production through a waste liquid recycling system, demonstrating strong practicality and promising application prospects. Attached Figure Description

[0024] The following is a brief explanation of the contents depicted in the accompanying drawings and the markings therein:

[0025] Figure 1 This is a schematic diagram of the chemical thinning process for electronic screens according to the present invention;

[0026] Figure 2 This is a structural block diagram of the electronic screen chemical thinning device of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0028] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0029] This invention discloses a high-precision, corrosion-free chemical thinning process for electronic screens, such as... Figure 1 As shown, the steps include:

[0030] S1. Fully enclosed UV coating protection and surface activation.

[0031] Select the electronic screen to be thinned and apply a high-temperature resistant (withstands temperatures above 80℃), acid and alkali resistant, and highly adhesive UV-cured protective film to protect the screen.

[0032] The protective film consists of a substrate layer and an adhesive layer: the substrate layer is made of polyimide (PI) or polyethylene terephthalate (PET) film, which has the properties of insulation, liquid impermeability and resistance to hydrofluoric acid corrosion; the adhesive layer is a UV photosensitive curing system, composed of acrylate oligomers, photoinitiators and reactive diluents.

[0033] After manual or automated lamination, the film completely covers the screen display area, IC chip, COF flexible cable, gold finger terminals, and exposed precision structures on the sides, ensuring no obstructions or gaps. Subsequently, it undergoes vertical UV curing at an intensity of 500-1500 mJ / cm² and a wavelength of 365 nm, causing the liquid adhesive layer to instantly cross-link and solidify, resulting in slight volume shrinkage (shrinkage rate ≤2%). This achieves zero-gap adhesion between the film layer and the screen substrate, circuit edges, and irregular gaps, forming a dense, integrated, fully sealed insulating protective layer in all non-thinned areas of the screen.

[0034] The cured film has a dense structure without micropores and a porosity of ≤0.5%. It has high insulation performance, with a breakdown voltage of ≥15kV / mm, which can isolate the etching solution from the electrochemical corrosion of metal lines and chip pins. It can also seal micro capillary gaps with a sealing width of ≤5μm, completely preventing acidic solutions from penetrating along the edges of the lines and interlayer gaps, and physically preventing the etching solution from seeping into non-processed areas.

[0035] After the coating is completed, the thinned area of ​​the glass substrate is subjected to plasma surface activation treatment. The treatment gas is oxygen or argon-oxygen mixture, the power is 200-500W, and the treatment time is 30-120s. This increases the surface energy of the exposed glass area and improves the uniformity of etching solution wetting.

[0036] S2, gradient graded chemical etching.

[0037] The protected screen is fixed in a vacuum adsorption fixture and sent into a sealed, constant temperature, dust-free etching chamber. A graded gradient etching solution is used to perform chemical thinning in steps, with the temperature controlled at 25-40℃ throughout the process. A low-temperature temperature control strategy is adopted to reduce etching stress and prevent the ultra-thin glass from breaking and warping.

[0038] First-stage coarse etching: A highly active etching solution is introduced into the etching chamber, rapidly removing 70%-85% of the glass substrate thickness using a dynamic spraying method, with an etching time of 3-8 minutes. The highly active etching solution consists of the following components by mass fraction: hydrofluoric acid (HF) 15%-22%, sulfuric acid 8%-15%, corrosion inhibitor 1%-3%, surfactant 0.5%-1.5%, and deionized water as the balance. This stage utilizes the high concentration of HF to rapidly erode the glass substrate, significantly reducing the substrate thickness. Simultaneously, the strong dehydrating properties of sulfuric acid promote the breaking of silicon-oxygen bonds on the glass surface, accelerating the etching reaction.

[0039] The second stage of fine etching involves switching the etching solution to a low-activity, low-intensity etching solution. This slow and precise etching method eliminates residual stress and surface defects from the initial rough etching, controlling the final thinning thickness. The etching time is 5-12 minutes. The low-activity, low-intensity etching solution consists of the following components by mass fraction: hydrofluoric acid (HF) 8%-12%, nitric acid 5%-10%, corrosion inhibitor 2%-4%, chelating agent 0.8%-2%, and deionized water as the balance. The introduction of nitric acid provides an oxidizing environment, promoting uniform corrosion of the glass surface, which, combined with the low concentration of HF, achieves precise thinning.

[0040] The aforementioned corrosion inhibitor is a compound of benzotriazole (BTA) and organophosphates (such as hydroxyethylidene diphosphonic acid HEDP) with a mass ratio of 1:1 to 3:1. It can form an adsorption film on the glass surface, effectively inhibiting local over-etching and improving surface smoothness.

[0041] Both of the above two etching processes employ dynamic spraying with a spraying pressure of 0.2-0.5 MPa. The spray heads are arranged in an array and can swing at multiple angles to ensure uniform distribution of etching solution in all areas of curved and irregularly shaped screens, thus eliminating edge effects.

[0042] S3. Online dynamic slag removal.

[0043] During the graded etching process, inert microbubbles, using nitrogen or argon gas, are simultaneously introduced into the etching chamber. Combined with ultrasonic oscillation, this rapidly removes the insoluble fluorosilicate residues generated during the etching reaction on the glass surface, preventing residue adhesion and uneven etching in certain areas. The ultrasonic oscillation frequency is 28-40 kHz, the average diameter of the microbubbles is 10-100 μm, and the bubble density is ≥10. 5 Microbubbles per mL, with a flow rate of 0.5-1.2 L / min. The microbubbles generate local disturbances during their ascent, which, combined with the ultrasonic cavitation effect, enables efficient stripping and dispersion of residues.

[0044] Microbubbles, with their large specific surface area and negative surface charge, preferentially adsorb reactive residue particles. Under the combined action of buoyancy and the sprayed liquid flow, they pull the residue away from the glass surface and carry it out of the etching area. The cavitation effect and microjets generated by ultrasonic oscillation physically break down and peel off the firmly adhered residue layer. Microbubbles, acting as preferential cavitation nuclei for ultrasonic cavitation, significantly reduce the cavitation threshold energy (approximately 30%-50%), concentrating the cavitation effect at the glass or solution interface and greatly improving residue removal efficiency. Ultrasonic oscillation simultaneously prevents excessive aggregation of microbubbles into large bubbles, maintaining a high-density distribution of small bubbles. Through these synergistic effects, the residue is peeled off and removed from the etching area within 0.5-2 seconds of formation, keeping the glass surface "fresh" and exposed to the etching solution at all times, achieving a residue removal efficiency of ≥90%.

[0045] S4, multi-stage countercurrent cleaning.

[0046] After etching, the screen sequentially enters a primary acid pickling tank, a secondary pure water rinsing tank, and a tertiary ultrapure water rinsing tank, using a counter-current circulation water supply system. Water from the tertiary tank is replenished to the secondary tank for reuse, then to the primary tank for reuse, and finally discharged. This means that the last stage of fresh ultrapure water overflows from the previous stage for reuse, thoroughly removing residual etching solution and impurities from the surface and conserving water. The primary acid pickling uses dilute hydrochloric acid or dilute sulfuric acid with a mass fraction of 3%-8%; the cleaning temperature is 30-45℃, and the cleaning time for each stage is 2-5 minutes, ensuring no chemical residue remains and preventing subsequent corrosion.

[0047] S5. Drying and Demolding.

[0048] The cleaned screen is dried using a combination of hot air drying and nitrogen blowing to completely remove moisture. The drying temperature is 50-70℃ and the drying time is 3-8 minutes.

[0049] Finally, the adhesive layer adhesion is significantly reduced by UV debonding process (light intensity 2000-4000mJ / cm², wavelength 365nm, irradiation time 30-90s), the protective film can be completely peeled off without any adhesive residue, and chemical thinning is completed.

[0050] This application also provides a high-precision, non-corrosive chemical thinning device for electronic screens, such as... Figure 2 As shown, it includes a frame, a feeding and conveying module, a fully enclosed protection module, a gradient etching module, a dynamic slag removal module, a multi-stage cleaning module, a drying and demolding module, a waste liquid recovery module, and a central control module.

[0051] The feeding and conveying module uses a belt conveyor and is equipped with a vacuum adsorption fixture. The fixture surface has contoured grooves and vacuum suction holes, which can stably fix flat screens, curved screens and irregularly shaped screens. The conveying speed is adjustable from 0.5-3m / min.

[0052] The fully enclosed protective module is arranged sequentially along the transmission direction, consisting of a plasma activation unit, a UV coating unit, and a curing unit. The plasma activation unit uses an atmospheric pressure plasma spray gun; the UV coating unit is equipped with a precision coating roller and an automatic cutting device; and the curing unit uses an LED-UV surface light source, realizing the integrated operation of automatic screen coating and surface activation.

[0053] The gradient etching module is a sealed, temperature-controlled, dust-free chamber (Class 100 cleanliness). It integrates a dual-channel independent chemical spray system, a high-precision temperature sensor (±0.5℃ accuracy), a laser and infrared dual-mode online fully automatic thickness detection unit, a real-time chemical parameter monitoring unit, and an adaptive control unit. The dual-channel independent chemical spray system stores high-activity and low-activity inhibitory etching solutions respectively. This module enables independent storage, supply, and automatic switching between the two gradient etching solutions, achieving seamless, fully automated transitions between coarse and fine etching processes. When the online detection unit detects that the remaining thickness has reached a set threshold, it automatically switches from the first-level etching solution to the second-level etching solution. The dual-mode online detection unit utilizes a combination of laser triangulation and infrared interferometry to achieve full-area, blind-spot-free thickness scanning with a detection accuracy of 0.1μm, supporting real-time data feedback and adaptive fine-tuning of process parameters. The chemical monitoring unit can monitor the etching solution concentration, pH value, temperature, and flow rate in real time, automatically replenishing the chemical solution and calibrating parameters to ensure stable etching conditions throughout the process.

[0054] The dynamic slag removal module integrates an inert gas supply unit (nitrogen generator or gas cylinder group) and an ultrasonic oscillation unit (frequency adjustable from 28-40KHz), and is integrated with the gradient etching module to complete the slag removal operation synchronously.

[0055] The multi-stage cleaning module is divided into three independent cleaning chambers, corresponding to acid washing, pure water washing, and ultrapure water washing, respectively. It adopts a counter-current water supply system, and each cleaning tank is equipped with an independent circulation pump and heater, which saves water while improving the cleaning effect.

[0056] Drying and Demolding Module: This module includes a hot air drying unit, a nitrogen blowing unit, and a UV debonding unit, integrating drying and demolding. The hot air drying unit has adjustable heating power, the blowing unit has adjustable flow rate, and the UV debonding unit uses a high-power LED-UV light source.

[0057] The waste liquid recovery module connects the gradient etching module and the multi-stage cleaning module via pipelines. It incorporates a filtration unit, a purification unit, and a circulation pump set. Through diffusion dialysis, precipitation filtration, and component replenishment, it filters, purifies, and recycles the waste liquid, reducing waste liquid discharge. The etching solution utilization rate is increased to over 85%, and waste liquid discharge is reduced by 70%. The built-in filtration unit is a precision filter with a filtration accuracy ≤1μm, and the purification unit uses ion exchange resin or an electrodialysis device.

[0058] The central control module uses a PLC programmable controller and a human-machine interface touch screen to realize full-process automated control, process parameter setting, data recording and alarm management.

[0059] This invention offers the following significant advantages: High precision and uniformity: Employing gradient etching technology, coarse etching rapidly removes the main body thickness, while fine etching precisely refines the surface quality. Combined with online dynamic slag removal and real-time thickness detection, the uniformity of screen glass thinning is ≤±0.01mm, and the surface roughness Ra≤3nm, eliminating defects such as over-etching, pits, and ripples, significantly improving screen transmittance and display accuracy. Comprehensive screen protection: Utilizing a fully sealed UV-cured protective film, ultraviolet light induces cross-linking and curing of the adhesive layer, resulting in micro-shrinkage and achieving zero-gap bonding between the film layer and the screen substrate, circuit edges, and irregular gaps. This forms a dense, integrated insulating protective layer, effectively blocking etching solution corrosion and completely preventing corrosion damage to screen circuits, IC chips, and ribbon cables, increasing the screen yield rate to over 98.5%. High adaptability: The vacuum adsorption fixture, combined with a multi-angle dynamic spray design, perfectly adapts to various electronic screens, including flat screens, curved screens, irregularly shaped screens, and automotive large screens, ensuring consistent thinning thickness across all areas and eliminating edge effects. Featuring low damage and high stability, the etching solution, combined with corrosion inhibitors and low-temperature control technology at 25-40℃, effectively reduces etching stress, decreasing the breakage and warpage rates by over 90% during the ultra-thin glass thinning process. It is suitable for thinning processing of ultra-thin screens below 50μm. The waste liquid recovery module achieves the recycling of etching solution through filtration and purification, increasing the utilization rate to over 85% and reducing waste liquid discharge by 70%, significantly lowering environmental treatment costs. The entire process is automated, requiring no manual intervention, and the processing time per batch is reduced by 40% compared to traditional processes, making it suitable for large-scale thinning production of electronic screens.

[0060] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the implementation of the present invention is not limited thereto.

[0061] Example 1 uses a curved mobile phone screen glass with a thickness of 0.4mm and a size of 6 inches as an example.

[0062] S1: A UV liquid protective film (viscosity 1500cps) containing benzotriazole-modified acrylate was vacuum-sprayed onto the IC chip and COF cable area, cured with 365nm UV for 120s, and the film thickness was approximately 50μm. Subsequently, the glass thinning surface was subjected to oxygen plasma treatment (power 300W, time 60s).

[0063] S2: Fix the screen to the curved vacuum fixture. First-stage coarse etching solution: HF 18%, H2SO4 10%, corrosion inhibitor 2%, surfactant 1%, balance water. Spray at 35℃ for 5 minutes, reducing the thickness from 0.4mm to 0.12mm. Second-stage fine etching solution: HF 10%, HNO3 6%, corrosion inhibitor 3%, chelating agent 1%, balance water. Spray at 35℃ for 8 minutes, achieving a final thickness of 0.07mm. Spray pressure: 0.35MPa.

[0064] Online thickness detection: laser interferometry, accuracy ±0.5μm, threshold set at 0.09mm, automatic switching 1.5 seconds after reaching the threshold.

[0065] S3: Simultaneously introduce nitrogen microbubbles (average diameter 50 μm, flow rate 0.8 L / min, bubble density approximately 2 × 10⁻⁶). 5 (number / mL), ultrasonic frequency 35KHz, power density 1.0W / cm².

[0066] S4: Sequentially enter 5% dilute hydrochloric acid wash (40℃), pure water wash (40℃), and ultrapure water wash (40℃), with countercurrent water supply, and each chamber is cleaned for 2 minutes.

[0067] S5: After drying with hot air and nitrogen at 60℃, the protective film is completely peeled off by using 385nm UV for 5 minutes.

[0068] Results: Thickness uniformity ±0.007mm, Ra 2.5nm, no corrosion on ICs and cables, 8% breakage rate at 45μm thinning, and overall yield rate 98.7%.

[0069] Example 2 uses a 0.5mm thick rectangular screen glass (15.6 inches in size) for automotive use as an example.

[0070] S1: Same as Example 1, but the plasma processing power is increased to 400W and the time is 90s.

[0071] S2: The first-stage etching time is extended to 8 minutes, the second-stage etching time is 12 minutes, and the spray pressure is 0.4 MPa. The online thickness detection threshold is set to the target thickness of 0.10 mm + 0.03 mm = 0.13 mm.

[0072] S3-S5: Same as Example 1.

[0073] Results: Final thickness 0.10 mm, thickness difference between edge and center ≤ 0.010 mm, surface roughness Ra 2.8 nm, no etching ripples, yield 98.2%.

[0074] Comparative Example 1 uses a conventional process with conventional ink protection (screen printing + baking at 150°C for 30 min), single-stage etching (HF 18%, 35°C, 13 min), no slag removal, and the rest is the same as in Example 1.

[0075] Results: Corrosion protection rate 13.3%, thickness uniformity ±0.034mm, Ra 8.2nm, 45μm fragmentation rate 35%, overall yield 82%.

[0076] Comparative Example 2 (Improved Process: Dry Film + Single-Stage Etching + Post-Cleaning) uses traditional dry film protection (hot rolling bonding + UV curing), single-stage etching (HF 18%, 35℃, 13min), and ultrasonic cleaning after etching (35KHz, 3min), the rest is the same as Example 1.

[0077] Results: Corrosion protection rate 6.7%, thickness uniformity ±0.021mm, Ra 6.5nm, 45μm fragmentation rate 22%, overall yield 89%.

[0078] Comparative Example 3 (two-stage etching + manual switching + no slag removal) uses the UV protective film of the present invention, two-stage etching (manual timing switching: 5min + 8min), no slag removal, and the rest is the same as Example 1.

[0079] Results: The yield rate of protective products was 98.2%, the thickness uniformity was ±0.012mm, the Ra value was 4.1nm, the 45μm fragmentation rate was 25%, and the overall yield rate was 91%.

[0080] Comparative Example 4 (two-stage etching + manual switching + ultrasonic cleaning after etching) uses the UV protective film of the present invention, two-stage etching (manual timing switching: 5min + 8min), ultrasonic cleaning after etching (35KHz, 3min), and the rest is the same as Example 1.

[0081] Results: The yield rate of protective products was 98.2%, the thickness uniformity was ±0.010mm, the Ra value was 3.5nm, the 45μm fragmentation rate was 18%, and the overall yield rate was 93.5%.

[0082] Comparative Example 5 (complete solution but without online detection and automatic switching) uses the UV protective film of the present invention, two-stage etching (manual timing switching: 5min + 8min), and microbubble + ultrasonic synchronous slag removal of the present invention (same parameters as Example 1), and the rest is the same as Example 1.

[0083] Results: The yield rate of protective products was 98.5%, the thickness uniformity was ±0.009mm, Ra was 3.2nm, the 45μm fragmentation rate was 12%, and the overall yield rate was 95%.

[0084] Comparative Example 6 (ultrasound + microbubbles but no synergistic optimization) uses the UV protective film of this invention, two-stage etching (online detection with automatic switching), and the slag removal method is ultrasound + microbubbles (but the microbubble diameter is not controlled (100-500μm), the density is low (about 10³ bubbles / mL), and no synergistic effect of bubbles as cavitation nuclei is formed), the rest is the same as Example 1.

[0085] Results: The yield rate of protective products was 99.0%, the thickness uniformity was ±0.009mm, the Ra value was 3.0nm, the residue was 0.06g / m², the 45μm fragmentation rate was 12%, and the overall yield rate was 96%.

[0086] In this application, the breakage rate refers to the percentage of screens with any visible cracks or breaks in the glass substrate after the completion of all thinning processes, as determined by visual inspection and microscopic examination, out of the total number of processed screens. The 'overall yield' refers to the percentage of screens that simultaneously meet all quality standards, including thickness uniformity (≤±0.01mm), surface roughness (Ra≤3nm), no line corrosion, and no breakage, out of the total number of processed screens.

[0087] Protection affects the basic yield rate, two-stage etching affects uniformity, and slag removal affects surface defects and breakage rate. Their effects are complementary rather than additive, achieving a comprehensive yield rate of 98.7%, far exceeding any single or pairwise combination.

[0088] The overall yield rate of Example 1 (complete solution) (98.7%) is 3.7 percentage points higher than that of Comparative Example 5 (lacking online detection, 95%), 2.7 percentage points higher than that of Comparative Example 6 (lacking synergistic optimization, 96%), 5.2 percentage points higher than that of Comparative Example 4 (lacking simultaneous slag removal, 93.5%), and 16.7 percentage points higher than that of Comparative Example 1 (traditional, 82%). These data fully demonstrate the significant synergistic effect among the three core features of this invention.

[0089] The electronic screen chemical thinning process and apparatus provided by this invention achieve precise control of thinning thickness and significant improvement of surface quality through gradient etching technology; completely eliminate the corrosion of non-processed areas such as screen circuits and chips by etching solution through fully enclosed UV curing coating protection technology; promptly remove reaction residues and eliminate local etching blind spots through online dynamic slag removal technology; reduce thinning stress and prevent ultra-thin glass from breaking and warping through low temperature control and corrosion inhibitor formula; and achieve green production through waste liquid recycling system.

[0090] The electronic screen chemical thinning process and apparatus provided by this invention can realize fully automated continuous production and is applicable to the thinning processing of various screens such as smartphones, tablets, automotive displays, and wearable devices, and has extremely high industrialization value.

[0091] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in the details for the sake of brevity.

[0092] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

[0093] The present invention has been described above by way of example with reference to the accompanying drawings. However, the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention or any direct application to other situations shall fall within the protection scope of the present invention.

Claims

1. A chemical thinning process for electronic screens, characterized in that, Includes the following steps: S1. Fully enclosed UV coating protection is applied to the non-thinning areas of the electronic screen, and plasma surface activation is applied to the thinning areas. S2. Gradient-level dynamic spray etching is performed using high-activity etching solution and low-activity corrosion-inhibiting etching solution to complete the thinning of the glass substrate; S3. During the etching process, online dynamic slag removal is performed simultaneously through ultrasonic vibration and inert microbubbles; S4. Multi-stage countercurrent cleaning removes residual chemicals and impurities; S5. After drying, UV debonding and film removal are performed to complete the thinning.

2. The electronic screen chemical thinning process according to claim 1, characterized in that: The protective film used in the fully enclosed UV coating protection in step S1 includes a polyimide or polyethylene terephthalate substrate layer and a UV photosensitive curable adhesive layer. The curing light intensity is 500-1500 mJ / cm², the porosity of the cured film layer is ≤0.5%, and the breakdown voltage is ≥15kV / mm.

3. The electronic screen chemical thinning process according to claim 1, characterized in that: The treatment gas for plasma surface activation in step S1 is oxygen or an argon-oxygen mixture, with a power of 200-500W and a treatment time of 30-120s.

4. The electronic screen chemical thinning process according to claim 1, characterized in that: The high-activity etching solution in step S2 consists of the following components by mass fraction: 15%-22% hydrofluoric acid, 8%-15% sulfuric acid, 1%-3% corrosion inhibitor, 0.5%-1.5% surfactant, and the balance of deionized water; the low-activity corrosion-inhibiting etching solution consists of the following components by mass fraction: 8%-12% hydrofluoric acid, 5%-10% nitric acid, 2%-4% corrosion inhibitor, 0.8%-2% chelating agent, and the balance of deionized water; the corrosion inhibitor is a compound of benzotriazole and organophosphate, with a compounding mass ratio of 1:1 to 3:

1.

5. The electronic screen chemical thinning process according to claim 1, characterized in that: The gradient-level dynamic spray etching described in step S2 includes a first-stage coarse etching and a second-stage fine etching: the etching temperature is 25-40℃, the coarse etching time is 3-8 min, removing 70%-85% of the thickness of the glass substrate; the fine etching time is 5-12 min; the spray pressure for both stages of etching is 0.2-0.5 MPa.

6. The electronic screen chemical thinning process according to claim 5, characterized in that: The frequency of the ultrasonic oscillation in step S3 is 28-40KHz, the flow rate of the inert microbubbles is 0.5-1.2L / min, and the inert gas is nitrogen or argon.

7. The electronic screen chemical thinning process according to claim 1, characterized in that: The multi-stage countercurrent cleaning in step S4 includes a first-stage acid washing, a second-stage pure water washing, and a third-stage ultrapure water washing. The cleaning temperature is 30-45℃, and the cleaning time for each stage is 2-5 minutes. A countercurrent circulation water supply method is used.

8. The electronic screen chemical thinning process according to claim 1, characterized in that: The drying process in step S5 is a combination of hot air drying and nitrogen blowing, with a drying temperature of 50-70℃ and a drying time of 3-8 minutes; the UV gelling process involves a light intensity of 2000-4000 mJ / cm² and an irradiation time of 30-90 seconds.

9. An electronic screen chemical thinning apparatus for implementing the process described in any one of claims 1-8, characterized in that: It includes a frame, a feeding and conveying module, a fully enclosed protection module, a gradient etching module, a dynamic slag removal module, a multi-stage cleaning module, a drying and demolding module, a waste liquid recovery module, and a central control module; The feeding and conveying module adopts a belt conveyor line and is equipped with a vacuum adsorption fixture that is compatible with flat screens, curved screens and irregularly shaped screens. The fully enclosed protective module is sequentially equipped with a plasma activation unit, a UV coating unit, and a curing unit along the transmission direction. The gradient etching module is a sealed, constant temperature, and dust-free chamber structure, with a built-in dual-path independent chemical spraying system, temperature sensor, laser + infrared dual-mode online fully automatic thickness detection unit, chemical parameter real-time monitoring unit, and adaptive control unit, realizing independent storage, supply, and automatic switching of the two gradient etching solutions. The dynamic slag removal module integrates an inert gas supply unit and an ultrasonic vibration unit, and is integrated with the gradient etching module. The multi-stage cleaning module is divided into three independent cleaning chambers and adopts a counter-current water supply system. The drying and decoction module includes a hot air drying unit, a nitrogen blowing unit, and a UV degumming unit. The waste liquid recovery module connects the gradient etching module and the multi-stage cleaning module, and has a built-in filtration unit and purification unit to realize the recycling of waste liquid.

10. The electronic screen chemical thinning device according to claim 9, characterized in that: The dual-mode online fully automatic thickness detection unit has a detection accuracy of 0.1μm; the real-time chemical solution parameter monitoring unit can detect the concentration, pH value, temperature and flow rate of the etching solution in real time, and automatically complete the chemical solution replenishment and parameter calibration; the waste liquid recovery module has a filtration accuracy of ≤1μm and an etching solution recycling rate of ≥85%.

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