Method for detecting warping stability of glass substrate and glass grinding equipment

Abstract

The invention discloses a method for detecting the warping stability of a glass substrate and glass grinding equipment, and relates to the field of glass substrate detection.The method for detecting the warping stability of the glass substrate comprises the steps that glass is pretreated, and the pretreated glass is subjected to high-temperature baking and cooling; detecting the warpage value of the cooled glass, carrying out high-temperature baking again, and repeating the operation for multiple times; summarizing the data of the warping values after multiple times of detection, and sorting the summarized data to pick out glass with qualified warping degree and glass with unqualified warping degree; according to the method, warping correction is carried out on the glass with the unqualified warping degree, the glass subjected to warping correction is detected so as to detect the warping value of the glass, and qualified products and unqualified products are picked out, and the change conditions of the glass under different temperature conditions can be simulated through multiple times of high-temperature baking and detection; therefore, the warping phenomenon possibly occurring in actual use can be predicted and prevented.

Description

Technical Field

[0001] The present application relates to the field of glass substrate detection, and in particular to a method for detecting warping stability of a glass substrate and a glass grinding device. Background Art

[0002] With the vigorous development of the display panel industry at home and abroad, domestic display panel technology has also developed rapidly. Glass substrate is the key glass material for thin-film transistors, and as an important component of the panel, it has become particularly important. In the process of liquid crystal display, the warping of the glass substrate is particularly important. Once the warping of the glass substrate is unstable and changes during the process, it will greatly damage the probes and other precision devices of the process equipment, causing irreparable losses. Therefore, in the production of glass substrates, the warping of the glass substrate needs to be strictly controlled. However, at present, glass substrate manufacturers are more focused on warping quality control of the glass substrate itself. When other quality parameters meet the control standards and the warping also meets the control standards, they will be packaged. There is almost no warping evaluation and detection for the process technology of liquid crystal displays that require multiple high-temperature baking. Therefore, in the process of liquid crystal displays, it is difficult to ensure that the warping of the glass substrate will not fluctuate due to multiple high-temperature baking. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention provides a method for detecting the warping stability of a glass substrate, comprising:

[0004] Step 1: pre-treat the glass and bake the pre-treated glass at high temperature;

[0005] Step 2: Cooling the glass after high-temperature baking;

[0006] Step 3: Detecting the warpage value of the cooled glass;

[0007] Step 4: The tested glass is again baked at high temperature, and steps 1 to 3 are repeated multiple times;

[0008] Step 5: Summarize the warpage values ​​after multiple tests, and sort out the summarized data to select glasses with qualified warpage and glasses with unqualified warpage;

[0009] Step 6: Correct the warping of the glass that does not meet the requirements, and perform steps 1 to 3 on the warping-corrected glass to detect the warping value of the glass, and select qualified products from unqualified products, store the qualified products, and discard the unqualified products.

[0010] Optionally, in some embodiments of the present application, in step 1, the glass includes stabilized front glass and stabilized rear glass, the stabilized front glass includes glass before heating in the pretreatment process, and the stabilized rear glass includes glass after heating in the pretreatment process;

[0011] The pre-processing of the glass includes cutting the glass, and the cutting size is 500mm*500mm.

[0012] Optionally, in some embodiments of the present application, in step 1, the temperature range of high temperature baking is: 200°C-250°C.

[0013] Optionally, in some embodiments of the present application, in step 3, the warping value includes a maximum warping value deviation and an average warping value deviation.

[0014] Optionally, in some embodiments of the present application, in step 5, when the maximum warping deviation is ≤0.01 mm and the average warping deviation is ≤0.005 mm, the glass is qualified glass.

[0015] Optionally, in some embodiments of the present application, in step 5, the warpage correction includes:

[0016] Step 501: Rotating and grinding the glass by glass grinding equipment;

[0017] Step 502: wet-etching the ground glass;

[0018] Step 503: Detect the warpage of the glass after wet etching. If the glass is qualified, store the qualified glass. If the glass is unqualified, discard the unqualified glass.

[0019] Optionally, in some embodiments of the present application, in step 501, the glass grinding equipment is provided with grinding pressure, grinding speed and grinding particle size, the grinding pressure includes 100g-500g, the grinding speed includes 10r / min-40r / min, and the grinding particle size includes 3μm-4μm.

[0020] Optionally, in some embodiments of the present application, in step 502, the wet etching includes a corrosive solution, and the corrosive solution is formed by mixing hydrochloric acid and phosphoric acid.

[0021] Optionally, in some embodiments of the present application, the volume ratio of the hydrochloric acid to the phosphoric acid is 1:3.

[0022] Optionally, in some embodiments of the present application, a glass grinding device is further provided, the glass grinding device comprising:

[0023] The grinding disc is rotated horizontally by a rotary drive device;

[0024] The pressurizing device includes a pressurizing groove and a pressurizing member, wherein the pressurizing member is located in the pressurizing groove, the glass is placed in the pressurizing groove, the notch of the pressurizing groove faces the grinding disc, and the pressurizing member applies pressure to the glass in the pressurizing groove so that the glass is ground on the grinding disc.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] 1. Through in-depth testing of the warping stability of glass, potential warping problems can be discovered and solved in a timely manner, thereby ensuring the quality and stability of the final product. This helps to improve the market competitiveness of the product and meet more stringent quality requirements.

[0027] 2. Through multiple high-temperature baking and testing, this method can simulate the changes of glass under different temperature conditions, thereby predicting and preventing warping that may occur in actual use, which helps to reduce product scrapping and rework caused by warping and reduce production costs.

[0028] 3. By analyzing the test data, we can understand the changes in the warping of the glass at different processing stages, and then optimize the production process, for example, adjust the baking temperature, time or grinding parameters to improve the warping stability of the glass.

[0029] 4. For unqualified products found during testing, the method provides effective corrective measures such as grinding correction and wet etching treatment, which helps to reduce product scrap rate and improve resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A schematic diagram of the overall process of a detection method for evaluating the warpage stability of a glass substrate provided in an embodiment of the present application;

[0032] Figure 2 This is a schematic diagram of the overall structure of the glass grinding equipment provided in an embodiment of the present application.

[0033] Description of reference numerals:

[0034] 100, grinding disc; 200, driving device; 300, pressurizing device; 310, pressurizing groove; 320, pressurizing member. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present application. It is understood that the drawings are only provided for reference and illustration, and are not used to limit the present application. The connection relationship shown in the drawings is only for the convenience of clear description and does not limit the connection method.

[0036] Specifically, Figure 1 As shown, a method for detecting the warping stability of a glass substrate is provided in an embodiment of the present application. The detection method mainly performs in-depth detection on the warping stability of the glass, and its purpose is to avoid the glass from warping in the later stage. To avoid this situation, in an embodiment of the present application, it is necessary to perform warping detection on the glass multiple times. First, the glass to be detected needs to be processed and pre-processed, wherein the glass that needs to be pre-processed includes glass before stabilization and glass after stabilization. The glass before stabilization is glass before the initial heating of the glass after production. This glass rarely warps and can be used as a control test for test detection. The glass after stabilization is glass after the initial heating of the glass after production. Since the occurrence of glass warping will be affected by temperature, the glass after the initial heating will have a probability of warping, but it is not obvious. In order to highlight the warping phenomenon, it is necessary to perform multiple baking tests on these two types of glass to make a comparison effect.

[0037] And in the embodiment of the present application, the pre-treatment process mainly includes: cutting the glass, and the cutting size is 500*500mm, and cleaning the cut glass with ultrapure water.

[0038] In the above description, the cut glass is divided into 8 pieces, including 4 pieces of glass before stabilization, which are labeled Q1, Q2, Q3, and Q4, and 4 pieces of glass after stabilization, which are labeled H1, H2, H3, and H4.

[0039] After the glass is pre-treated, the glass before stabilization and the glass after stabilization are respectively subjected to high-temperature baking. The high-temperature baking is performed in an electric heating oven. First, the electric heating oven heats up from room temperature, and after 50 minutes, the temperature is raised to 230°C, and then kept warm at 230°C.

[0040] Preferably, the temperature range of high temperature baking in the embodiment of the present application can be selected as: 200°C-250°C, which can produce a good warping catalytic effect on the glass without affecting other properties of the glass.

[0041] In the electric heating oven, the glasses to be tested are placed obliquely in the oven, and the glasses to be tested are arranged in sequence and spaced apart so that the glasses do not touch each other, thereby avoiding the influence between the glasses.

[0042] In the above, the glass is continuously baked in the electric heating oven for 30 minutes. After 30 minutes, the glass to be tested is taken out of the electric heating oven and placed in an external environment for cooling, so that the glass is cooled to the ambient room temperature.

[0043] The glass after cooling is tested by a warpage tester, wherein the testing process is as follows:

[0044] The glass substrate samples Q1, Q2, Q3, Q4 and H1, H2, H3, H4 treated at high temperature in the above steps are respectively tested for warpage using a warpage measuring instrument, and the maximum warpage value and the average warpage value of the glass substrate samples Q1, Q2, Q3, Q4 and H1, H2, H3, H4 are recorded;

[0045] In the embodiment of the present application, the data of the maximum warpage value and the average warpage value are the change values ​​after the first high temperature treatment.

[0046] After the first test, the glass after the preliminary test is put into the electric heating oven again, and the glass substrate samples Q1, Q2, Q3, Q4 and H1, H2, H3, H4 after the medium and high temperature treatment are heated again in the electric heating device. After heating, the warpage is tested again by the warpage measuring instrument, and the maximum warpage value and the average warpage value of the glass substrate samples Q1, Q2, Q3, Q4 and H1, H2, H3, H4 are recorded;

[0047] After recording the corresponding probabilities, the glass substrate is put into the electric heating oven again. The electric heating oven heats the two batches of glass substrates three times and performs detection again to obtain corresponding data.

[0048] The above operation is cycled for 5 times in total in the embodiment of the present application, and each cycle includes heating and detection.

[0049] After five cycles, the data recorded five times were sorted and summarized, and the summarized data results are as follows:

[0050]

[0051]

[0052] Table 1: Glass substrate sample data before stabilization

[0053]

[0054]

[0055] Table 2: Data of stabilized glass substrate samples

[0056] In the above table, the glass substrate samples are judged by the maximum warpage deviation and the average warpage deviation. When the maximum warpage deviation is ≤0.01nm and the average deviation is ≤0.005nm, it can be determined that the glass substrate sample has good warpage stability and better quality and can be used as a subsequent product.

[0057] Among them, when the warping deviation value in this application is not within the above range, it is determined that the glass substrate sample has poor warping stability and poor quality, and it is not recommended to be directly used as a subsequent product.

[0058] In order to better verify the determination results of the above experiments, and further verify the feasibility and accuracy of the technical solution of the method of the present invention, processes were performed on the glass substrates before and after the warping was stabilized, and the accuracy was further verified by the results after the processes.

[0059] Specifically, 10 glass substrates were selected before and after the warpage stabilization for processing, and the process integrity rate of the final 10 substrates and the film integrity of the glass substrates were counted to verify the accuracy of the results.

[0060] (1) The warpage of the glass substrate is measured before and after the warpage is stabilized to determine the warpage value:

[0061] Warpage value / mm Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Maximum 0.286 0.265 0.324 0.315 0.317 0.189 0.176 0.195 0.177 average value 0.215 0.208 0.219 0.211 0.209 0.168 0.167 0.169 0.171 Warpage value / mm H2 H3 H4 H5 H6 H7 H8 H9 H10 Maximum 0.082 0.089 0.075 0.068 0.074 0.054 0.059 0.092 0.101 average value 0.044 0.038 0.051 0.039 0.042 0.041 0.038 0.042 0.051

[0062] (2) 10 glass substrates before and after warpage stabilization are respectively prepared, and the glass substrates are specifically manufactured in combination with the process flow of the front-end station of the liquid crystal display: input of ITO glass - glass cleaning and drying - photoresist coating - pre-baking - exposure and development - etching - film removal - image inspection - cleaning and drying - TOP coating - baking - curing - cleaning - coating of alignment agent - curing - cleaning screen printing - baking - spraying of liner material - alignment and pressing - curing, etc.;

[0063] (3) The process integrity rate and film integrity of 10 glass substrates before and after the warpage stabilization were counted respectively:

[0064]

[0065] A glass film is placed on the glass substrate. When the glass substrate is repeatedly subjected to high temperature and testing, the stability of the glass film on the glass substrate is checked to determine the degree of glass warping. The result is the warping value in the above table. From the above table, we can understand that:

[0066] The maximum value of the warping value of the glass substrate after stabilization is about 0.1, and the average value is about 0.05, which is much smaller than the warping degree data of the glass substrate before stabilization, further verifying the operability and accuracy of the technical solution of the method of the present invention.

[0067] After verifying the feasibility of this application, it is necessary to correct the warping of unqualified products and process and test the glass substrate samples again to further determine the warping stability of the glass substrate samples.

[0068] Among them, warpage correction includes:

[0069] The glass is rotationally ground by a glass grinding device, and the glass is the glass that does not meet the corresponding requirements after the above detection.

[0070] In rotary grinding, the glass grinding equipment mainly includes a grinding disc 100 and a pressurizing device 300. A rotary driving device is provided on the grinding disc 100. The rotary driving device drives the grinding disc 100 to rotate continuously. The rotary driving device is provided to process the rotary grinding in this application, so as to facilitate the processing of the glass substrate sample by rotary grinding.

[0071] Among them, the original film of the glass substrate is provided with a warping correction in the present application, and the pressurizing device 300 is provided with a pressurizing member 320 and a pressurizing groove 310, the pressurizing member 320 is located in the pressurizing groove 310, and the opening of the pressurizing groove 310 is facing the direction of the grinding disk 100, so that when the glass substrate sample is located in the pressurizing groove 310, the pressurizing member 320 pushes the glass substrate sample to move in the direction of the grinding disk 100, so that the grinding disk 100 grinds the glass substrate sample, wherein the glass substrate grinding processes the glass substrate.

[0072] During the grinding process, the pressure member 320 is located in the pressure groove 310, so that the pressure member 320 can move in the pressure groove 310 to push the glass substrate sample until the side of the glass substrate sample close to the grinding disk 100 abuts against the grinding disk 100, and the grinding disk 100 grinds and polishes the glass substrate sample.

[0073] The grinding parameters of the glass substrate on the grinding disc 100 include: the grinding pressure is set at 100g-500g, the grinding speed is set at 10-40r / min, and the grinding particle size is set at 3-4μm.

[0074] In the above, the grinding disc 100 is set to perform preliminary processing on the glass substrate sample. To ensure a better grinding effect, the grinding duration is about 2-3 minutes. After the grinding is completed, the ground glass substrate sample is wet-etched. The wet etching process is mainly processed by a etching solution, which includes hydrochloric acid and phosphoric acid.

[0075] In order to achieve better results, the volume ratio of hydrochloric acid to phosphoric acid in the embodiment of the present application is 1:3. During the grinding process, hydrochloric acid mainly corrodes the glass substrate, and phosphoric acid is mainly used as a diluent corrosion inhibitor for viscosity adjustment.

[0076] The above grinding process requires immersion grinding in an acidic solution.

[0077] The pickling solution corrodes the glass substrate, which needs to be rinsed after corrosion. After rinsing, the glass substrate samples are subjected to multiple high-temperature baking and warpage tests. When the final test is qualified, the qualified glass substrate samples are stored. When the final test shows that the glass is unqualified, the unqualified glass is discarded.

[0078] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A method for detecting the warpage stability of a glass substrate, characterized in that: include: Step 1: pre-treat the glass and bake the pre-treated glass at high temperature; Step 2: Cooling the glass after high-temperature baking; Step 3: Detecting the warpage value of the cooled glass; Step 4: The tested glass is again baked at high temperature, and steps 1 to 3 are repeated multiple times; Step 5: Summarize the warpage values ​​after multiple tests, and sort out the summarized data to select glasses with qualified warpage and glasses with unqualified warpage; Step 6: Correct the warping of the glass that does not meet the requirements, and perform steps 1 to 3 on the warping-corrected glass to detect the warping value of the glass, and select qualified products from unqualified products, store the qualified products, and discard the unqualified products.

2. A method for detecting warpage stability of a glass substrate according to claim 1, characterized in that: In step 1, the glass includes stabilized front glass and stabilized rear glass, wherein the stabilized front glass includes glass before being heated in the pretreatment process, and the stabilized rear glass includes glass after being heated in the pretreatment process; The pre-processing of the glass includes cutting the glass, and the cutting size is 500mm*500mm.

3. The method for detecting the warpage stability of a glass substrate according to claim 1, characterized in that: In the step 1, the temperature range of the high temperature baking is: 200°C-250°C.

4. The method for detecting the warpage stability of a glass substrate according to claim 1, characterized in that: In step 3, the warping value includes a maximum warping value deviation and an average warping value deviation.

5. The method for detecting the warpage stability of a glass substrate according to claim 4, characterized in that: In the step 5, when the maximum warpage deviation is ≤0.01 mm and the average warpage deviation is ≤0.005 mm, the glass is qualified glass.

6. The method for detecting the warpage stability of a glass substrate according to claim 5, characterized in that: In step 5, the warpage correction includes: Step 501: Rotating and grinding the glass by glass grinding equipment; Step 502: wet-etching the ground glass; Step 503: Detect the warpage of the glass after wet etching. If the glass is qualified, store the qualified glass. If the glass is unqualified, discard the unqualified glass.

7. The method for detecting the warpage stability of a glass substrate according to claim 6, characterized in that: In the step 501, the glass grinding equipment is provided with grinding pressure, grinding speed and grinding particle size, wherein the grinding pressure is 100g-500g, the grinding speed is 10r / min-40r / min, and the grinding particle size is 3μm-4μm.

8. The method for detecting the warpage stability of a glass substrate according to claim 6, characterized in that: In step 502, the wet etching includes a etching solution, and the etching solution is a mixture of hydrochloric acid and phosphoric acid.

9. The method for detecting the warpage stability of a glass substrate according to claim 9, characterized in that: The volume ratio of the hydrochloric acid to the phosphoric acid is 1:

3.

10. A glass grinding device, used to perform a method for detecting warpage stability of a glass substrate according to any one of claims 1 to 9, characterized in that: The glass grinding equipment comprises: The grinding disc is rotated horizontally by a rotary drive device; The pressurizing device includes a pressurizing groove and a pressurizing member, wherein the pressurizing member is located in the pressurizing groove, the glass is placed in the pressurizing groove, the notch of the pressurizing groove faces the grinding disc, and the pressurizing member applies pressure to the glass in the pressurizing groove so that the glass is ground on the grinding disc.

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