Curved glass free polishing heat bending process

Abstract

The disclosure provides a curved glass polishing-free heat bending process, which comprises the following steps: (1) spraying a ceramic powder slurry on a graphite heat bending mold, wherein the ceramic powder slurry is formed by mixing ceramic powder and anhydrous alcohol, and the ceramic powder and the anhydrous alcohol are mixed in a weight ratio of 3:1 to 1:1; (2) baking the sprayed graphite heat bending mold to bond and solidify the graphite heat bending mold and the ceramic powder slurry; and (3) using the solidified graphite heat bending mold to perform heat bending on a glass blank to form a curved glass. No subsequent polishing repair process is required, the process is reduced, the secondary defective scrap rate caused by the polishing repair process is avoided, the direct and indirect costs caused by the polishing repair of the prior art are eliminated, the product quality of the curved glass is effectively ensured, and the production cost of the curved glass is reduced.

Description

Technical Field

[0001] This disclosure relates to the field of glass processing technology, and in particular to a hot bending process for curved glass without polishing. Background Technology

[0002] Curved glass is being used more and more widely, for example in mobile phones and automotive devices, where 2D curved glass and 3D curved glass are already in common use.

[0003] The existing manufacturing process for curved glass mainly involves: CNC trimming of the glass blank (i.e., trimming with a CNC machine tool), followed by hot bending using a graphite mold, and then double-sided polishing of the formed curved glass.

[0004] However, the aforementioned existing curved glass processing technology has a high processing cost and several problems, specifically:

[0005] First, after being hot-bent using a graphite mold, the 3D curved glass surface has defects such as mold marks and indentations, which need to be repaired by polishing. After one side is repaired, the next side needs to be switched to continue the repair process, which is complicated.

[0006] However, the polishing and repair process of curved glass often leads to secondary defects, such as scratches and breakage. This results in a large number of scrapped curved glass products. In addition, the polishing and repair process requires a lot of consumables, such as polishing brushes, polishing powder, and concave / convex polishing fixtures. This situation leads to the high manufacturing cost of curved glass.

[0007] Secondly, in the existing curved glass processing technology, the wear rate of graphite molds is very high. After processing about 500 glass blanks, they will reach the scrap stage, and the cost of graphite molds themselves is also too high.

[0008] In view of this, there is a need to design a better curved glass processing technology that can eliminate or mitigate the defects of one or more of the above-mentioned existing technologies. Summary of the Invention

[0009] One of the technical problems to be solved by this disclosure is to provide a curved glass polish-free hot bending process, which can improve the surface smoothness and other appearance quality of curved glass without the need for subsequent curved glass polishing process.

[0010] To solve the above technical problems, this disclosure provides a curved glass hot bending process without polishing, which includes the following steps: (1) spraying a ceramic powder slurry onto a graphite hot bending mold, wherein the ceramic powder slurry is formed by mixing ceramic powder and anhydrous alcohol, and the ceramic powder and anhydrous alcohol are mixed in a weight ratio of 3:1 to 1:1; (2) baking the sprayed graphite hot bending mold to make the graphite hot bending mold and the ceramic powder slurry bond and solidify; (3) using the solidified graphite hot bending mold to perform hot bending operation on the glass blank to form curved glass.

[0011] In some embodiments, the ceramic powder comprises, by weight percentage: 35-60% silicon carbide, 15%-43% silicon powder, 3-10% alumina, 4-15% boron carbide, and 3-4% zirconium oxide as a combustion aid.

[0012] In some embodiments, prior to step (1), the surface finish of the cavity of the graphite hot bending mold is further subjected to surface treatment.

[0013] In some embodiments, the surface finish treatment is a polishing process applied to the cavity of the graphite hot bending die.

[0014] In some embodiments, in step (2), the coated graphite hot bending mold is baked at a temperature of 300℃-500℃ for 20-40 minutes.

[0015] In some embodiments, the coated graphite hot bending mold is baked at 400°C for 30 minutes.

[0016] In some embodiments, in step (3), a hot bending operation is performed at a temperature of 650°C-850°C for 20-40 minutes, and after baking and curing, the cavity of the graphite hot bending mold is coated with paraffin wax doped with carbon black powder.

[0017] In some embodiments, a hot bending operation is performed at a temperature of 750°C for 30 minutes.

[0018] In some embodiments, the surface finish of the curved glass is inspected after the hot bending operation.

[0019] In some embodiments, after processing 150-250 pieces of curved glass using a graphite hot bending mold, the graphite hot bending mold is immersed and cleaned so that it can be reused after being recoated with ceramic powder slurry and baked to cure.

[0020] In some embodiments, the ceramic slurry is doped with glass powder of the same composition as the glass blank to be processed, wherein the weight of the glass powder is 1 / 50 to 1 / 30 of the weight of the ceramic powder.

[0021] Through the above technical solution, the curved glass polish-free hot bending process disclosed in this disclosure innovatively bonds cured ceramic powder onto a graphite hot bending mold, and uses the cured graphite hot bending mold to perform hot bending operations on the glass blank. The curved glass polish-free hot bending process of this disclosure has been proven in actual production. The processed curved glass has a good appearance, a smooth surface, and a finished product qualification rate of 98.2%. Curved glass of this quality does not require subsequent polishing and repair processes, reducing steps, avoiding secondary defect rates caused by polishing and repair processes, and eliminating the direct and indirect costs caused by existing polishing and repair technologies. This effectively ensures the product quality of curved glass and reduces the production cost of curved glass. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a flowchart illustrating the steps of the curved glass hot bending process without polishing disclosed in this embodiment. Detailed Implementation

[0024] The embodiments of this disclosure will be further described in detail below with reference to the accompanying drawings and examples. The detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of this disclosure by way of example, but should not be used to limit the scope of this disclosure. This disclosure can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0025] These embodiments are provided to make the disclosure thorough and complete, and to fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, material composition, numerical expressions, and values ​​set forth in these embodiments should be interpreted as exemplary only and not as limiting.

[0026] It should be noted that, in the description of this disclosure, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationship, are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0027] Furthermore, the terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. "Vertical" is not strictly vertical, but within the permissible margin of error. "Parallel" is not strictly parallel, but within the permissible margin of error. Terms such as "including" or "contains" mean that the element preceding the word encompasses the element listed after the word, and do not exclude the possibility of encompassing other elements as well.

[0028] It should also be noted that, in the description of this disclosure, unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure depending on the specific circumstances. When a particular device is described as being located between a first device and a second device, an intermediary device may or may not be present between the particular device and the first or second device.

[0029] All terms used in this disclosure have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0030] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0031] Example

[0032] See Figure 1 As shown, the present invention provides a hot bending process for curved glass without polishing, characterized by the following steps:

[0033] (1) Spraying ceramic powder slurry onto graphite hot bending abrasive, wherein the ceramic powder slurry is formed by mixing ceramic powder and anhydrous alcohol, and the ceramic powder and anhydrous alcohol are mixed in a weight ratio of 3:1 to 1:1.

[0034] (2) Bake the coated graphite hot bending mold to make the graphite hot bending mold bond and solidify with the ceramic powder slurry;

[0035] (3) Use the cured graphite hot bending mold to perform hot bending operation on the glass blank to form curved glass.

[0036] The curved glass hot bending process described in the above basic embodiment innovatively involves bonding and curing ceramic powder onto a graphite hot bending mold, and then using the cured graphite hot bending mold to perform hot bending on the glass blank. A unique technical key is the mixing of anhydrous alcohol and ceramic powder to form a ceramic powder slurry. This unique mixing method has been verified through extensive testing with actual products. Using water or other solvents often results in the ceramic powder slurry failing to effectively cure and bond to the graphite hot bending mold. This curved glass hot bending process without polishing has been proven in actual production. The processed curved glass has a good appearance, a smooth surface, and a finished product qualification rate of 98.2%. Curved glass of this quality requires no subsequent polishing or repair process, reducing steps and achieving a polish-free technical effect. This avoids secondary defects caused by polishing repair processes and eliminates the direct and indirect costs associated with existing polishing repair techniques, effectively ensuring the product quality of curved glass and reducing its production cost.

[0037] In some embodiments, the ceramic powder comprises, by weight percentage: 35-60% silicon carbide, 15%-43% silicon powder, 3-10% alumina, 4-15% boron carbide, and 3-4% zirconium oxide as a combustion aid. Although commercially available ceramic powder materials can generally achieve the above-mentioned technical effects of this disclosure, the ceramic powder formulation of this embodiment is a unique and dedicated formulation developed by the project team of this disclosure through arduous and creative work for the graphite hot bending mold coating process. In particular, the original use of the auxiliary materials alumina and boron carbide can effectively improve the toughness and certain plasticity of the ceramic powder slurry layer, and effectively reduce the micropores after the ceramic powder slurry layer is cured, resulting in higher processing quality of the finished product and higher smoothness of the glass plate.

[0038] In some embodiments, prior to step (1), a surface finish treatment may be performed on the cavity of the graphite hot bending mold. The hot bending mold is made of graphite, whose thermal conductivity is similar to that of glass. To prevent machining marks on the graphite mold itself from affecting the subsequent processing quality of curved glass, this surface finish treatment of the cavity can effectively eliminate surface impurities such as tool marks and particle points present during the graphite mold's own machining process. In other embodiments, the specific surface finish treatment may employ a polishing process, such as polishing the cavity of the graphite mold with sandpaper, typically using 5000# sandpaper for fine polishing.

[0039] To better bond and cure the sprayed ceramic powder slurry onto the graphite hot bending mold and enhance adhesion, in some embodiments, the sprayed graphite hot bending mold can be baked at 300℃-500℃ for 20-40 minutes, and after baking and curing, the cavity of the graphite hot bending mold is coated with paraffin wax doped with carbon black powder. This unique paraffin wax coating process can effectively further improve the processing quality of glass covers, especially in improving the smoothness of the glass covers and avoiding scratches invisible to the naked eye. Because the temperature during the hot bending operation is as high as 650℃-850℃, the paraffin wax doped with carbon black powder melts first, becoming liquid, and carries the carbon black powder to penetrate into the surface micropores that may exist in the cured ceramic powder slurry layer. As the temperature rises, the carbon dioxide and water formed by the combustion of paraffin wax evaporate, and the carbides formed after the carbon black powder burns seal the micropores, preventing these micropores from forming slight scratches on the surface of the glass cover, further improving the smoothness of the finished glass cover.

[0040] In some embodiments, the coated graphite hot bending mold can be baked at 400°C for 30 minutes. This baking time and temperature are more beneficial for the fusion, bonding, and curing of the ceramic powder and the graphite hot bending mold.

[0041] In order to avoid damage to the graphite hot bending mold itself due to excessive use and to create conditions for subsequent recycling of the mold, in some embodiments, the operating temperature and operating time in step (3) can be controlled. Specifically, the hot bending operation can be carried out at a temperature of 650℃-850℃ for 20-40 minutes.

[0042] Based on actual production tests, in some embodiments, hot bending can be performed at a temperature of 750°C for 30 minutes. This temperature and duration cause minimal damage to the graphite hot bending die itself and are most conducive to maintaining the service life of the graphite hot bending die.

[0043] In some embodiments, to prevent individual unintended defects in the curved glass non-polishing hot bending process of this disclosure, the surface finish of the curved glass can be checked after the hot bending operation. This way, if any defective products are found, the cause can be identified promptly, the processing parameters adjusted, and defective products can be prevented from mixing with qualified products.

[0044] In some embodiments, after processing 150-250 pieces of curved glass using a graphite hot bending mold, the mold is immersed in water for cleaning. This allows for the re-coating of ceramic powder slurry and subsequent baking and curing, enabling the mold to be reused. Through these embodiments, the usage time of the graphite hot bending mold is precisely controlled, resulting in minimal damage to the mold itself. Immersion cleaning allows for further ceramic powder coating and curing, enabling the mold to be reused. Actual testing shows that this recycling method can extend the lifespan of the graphite hot bending mold by up to four times; previously, a mold had to be scrapped after producing 500 pieces of curved glass, but now each mold can produce 2000 pieces.

[0045] In some embodiments, the sprayed ceramic powder slurry may contain glass powder with the same composition as the glass blank to be processed, wherein the weight part of the glass powder can be 1 / 50 to 1 / 30 of the weight part of the ceramic powder. This process feature is an improvement in the process formula achieved through extensive research and experimentation. In actual production, although the finished product qualification rate of this disclosure reaches 98.2%, occasionally there are still individual defective products of curved glass. Research has found that although the thermal conductivity of graphite and glass is similar, there are still some subtle differences. After the ceramic powder is bonded and cured on the surface of the graphite hot bending mold, there are certain differences in thermal deformation. After extensive improvement and trial production, the sprayed ceramic powder slurry may contain glass powder with the same composition as the glass blank to be processed, wherein the weight part of the glass powder can be 1 / 50 to 1 / 30 of the weight part of the ceramic powder. This can significantly and effectively further improve the finished product qualification rate. Through this technical improvement, the finished product qualification rate reaches 99.3%, further enhancing the technical advantages of the disclosed solution.

[0046] The above describes various implementation methods of the technical solution disclosed herein through some examples. The following describes a relatively comprehensive embodiment with reference to the actual production process.

[0047] In this relatively comprehensive embodiment, the hot bending mold is made of graphite. Because graphite's thermal conductivity is close to that of glass, it is more conducive to the processing of curved glass. The overall processing includes: First, polishing the cavity of the graphite hot bending mold with 5000# sandpaper to remove surface impurities such as tool marks and particle points from the processing; Second, uniformly spraying the inner and outer surfaces of the graphite hot bending mold with a prepared ceramic powder slurry; Third, after spraying the ceramic powder slurry, baking the graphite hot bending mold at 400℃ for 30 minutes (i.e., solidification baking, where the ceramic powder slurry is solidified), allowing the graphite hot bending mold and ceramic powder to fuse together, increasing adhesion and preventing detachment during use, thus providing a solidification and protective function; Fourth, after solidification baking, placing the graphite hot bending mold into the curved glass... For the processing of curved glass products, a graphite hot bending mold is used to perform a hot bending operation at 750℃ for 30 minutes to avoid damaging the graphite hot bending mold by continuous hot bending operations for too long. Fifth, after the hot bending operation of a single curved glass is completed, the surface of the curved glass is inspected to confirm its surface smoothness and other appearance effects. Sixth, after processing 200 pieces of curved glass with the graphite hot bending mold, the graphite hot bending mold is immersed in a cleaning solution. The immersion solution can be a commonly used cleaning agent. After immersion, the graphite hot bending mold is re-coated with ceramic powder slurry and then baked and cured. In this way, the graphite hot bending mold can be reused repeatedly. According to tests, the original lifespan of a graphite hot bending mold that can only process 500 pieces of curved glass can be extended to processing 2000 pieces of curved glass through this cyclical use.

[0048] As can be seen from the description of the above technical solution in this disclosure, the curved glass polish-free hot bending process of this disclosure eliminates the need for subsequent polishing and repair of the processed curved glass, achieving the technical effect of polish-free operation. It reduces the polishing process for curved glass, saves consumables such as polishing brushes, polishing jigs, and polishing liquids, reduces manufacturing costs, and effectively avoids secondary defects such as scratches and breakage caused by the polishing process of curved glass, thereby improving the product yield.

[0049] In addition, the technical solution disclosed herein also improves the service life of graphite hot bending dies, which can multiply the service life and reduce the wear on the surface of graphite dies.

[0050] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0051] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any manner.

Claims

1. A non-polishing hot bending process for curved glass, characterized in that, Includes the following steps: (1) A ceramic powder slurry is sprayed onto a graphite hot bending mold, wherein the ceramic powder slurry is formed by mixing ceramic powder with anhydrous alcohol, wherein the ceramic powder and anhydrous alcohol are mixed in a weight ratio of 3:1 to 1:1, and the ceramic powder slurry is also doped with glass powder with the same composition as the glass blank to be processed, wherein the weight part of the glass powder is 1 / 50 to 1 / 30 of the weight part of the ceramic powder, and the components of the ceramic powder include, by weight percentage: 35-60% silicon carbide, 15%-43% silicon powder, 3-10% alumina, 4-15% boron carbide, and 3-4% zirconium oxide as a combustion aid; (2) The graphite hot bending mold after spraying is baked at a temperature of 300℃-500℃ for 20-40 minutes so that the graphite hot bending mold and the ceramic powder slurry are bonded and cured, and after baking and curing, the cavity of the graphite hot bending mold is coated with paraffin wax doped with carbon black powder. (3) The glass blank is hot-bent using the cured graphite hot bending mold to form curved glass.

2. The curved glass non-polishing hot bending process according to claim 1, characterized in that, Before step (1), the surface finish of the cavity of the graphite hot bending mold is also performed.

3. The curved glass non-polishing hot bending process according to claim 2, characterized in that, The surface finish treatment involves polishing the cavity of the graphite hot bending mold.

4. The curved glass non-polishing hot bending process according to claim 1, characterized in that, In step (2), the coated graphite hot bending mold is baked at 400°C for 30 minutes.

5. The curved glass non-polishing hot bending process according to claim 1, characterized in that, In step (3), hot bending is performed at a temperature of 650℃-850℃ for 20-40 minutes.

6. The curved glass non-polishing hot bending process according to claim 5, characterized in that, Perform hot bending at 750℃ for 30 minutes.

7. The curved glass non-polishing hot bending process according to claim 1, characterized in that, It also includes checking the surface finish of the curved glass after the hot bending operation.

8. The curved glass hot bending process without polishing according to any one of claims 1 to 7, characterized in that, It also includes soaking and cleaning the graphite hot bending mold after processing 150-250 pieces of curved glass using the graphite hot bending mold, so that the graphite hot bending mold can be reused after recoating the ceramic powder slurry and baking and curing.

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