Method for processing three-dimensional LOGO on mobile phone glass cover plate

Abstract

The invention discloses a method for processing a three-dimensional LOGO on mobile phone cover plate glass, which comprises the following steps of: firstly, silk-screening protective ink on the surface of a glass cover plate to hollowed out a LOGO area, then generating a sunken structure in the hollowed-out LOGO area through chemical etching, and finally spraying contrast color ink to the LOGO area, so as to obtain the three-dimensional LOGO on the mobile phone cover plate glass. A strong three-dimensional visual effect is generated by utilizing the height difference of the sunken structure and the comparison of the two-color ink of the LOGO area and the non-LOGO area, the common interlayer stripping problem in the traditional process is avoided through the integrated ink design, the product yield is improved by 15-20%, and compared with the prior art, the product quality is improved by 20-30%. According to the method, a plurality of complex procedures such as photoresist coating, mask exposure, developing photoresist removal and functional film lamination are omitted, three-step method efficient production is achieved, the procedures are reduced by more than 50%, equipment investment and process time are greatly reduced, procedure connection and yield loss are reduced, and the surface decoration effect and production efficiency of the glass cover plate are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of mobile phone glass cover processing, and relates to a three-dimensional LOGO processing technology, specifically a method for processing a three-dimensional LOGO on a mobile phone glass cover. Background Art

[0002] With the continuous upgrading of the appearance design of smart phones, 2D, 2.5D and 3D curved glass front covers / rear covers have become the standard for high-end intelligent terminals due to their excellent visual effects and tactile experiences. Among them, to enhance product recognition, manufacturers usually make brand LOGOs or decorative patterns on the glass surface and endow them with a three-dimensional light and matte coexisting effect (that is, the coexistence of high-gloss and matte areas). At present, the industry mainly uses the processes of developing and exposing + etching + laminating or screen printing texture + etching + laminating to achieve such effects, but the existing technologies still have problems such as high cost, low yield, and complex processes, which are specifically manifested as follows:

[0003] 1. Developing and exposing + etching + laminating process

[0004] In this process, a photoresist is first coated on the glass surface, and a pattern of LOGO or texture is formed by exposure and development through a mask plate. Then, chemical etching (such as hydrofluoric acid solution) is used to corrode the unprotected area of the glass to form a three-dimensional concave-convex structure. Finally, an optical film layer is laminated to enhance the light and matte contrast effect. Its defects are as follows:

[0005] Complex process: It requires multiple processes such as coating, exposure, development, etching, degluing, cleaning, and laminating, with a long production cycle and large equipment investment.

[0006] High cost: The consumption of photoresist and etching solution is large, and the etching accuracy requirement is high, resulting in an increase in the cost of raw materials and waste liquid treatment.

[0007] Unstable yield: It is difficult to uniformly control the etching depth, and over-etching or residues are likely to occur. Especially on 3D curved glass, due to uneven stress distribution, edge serrations or cracks are more likely to occur.

[0008] 2. Screen printing texture + etching + laminating process

[0009] In this process, an anti-etching ink is directly printed on the glass surface through screen printing to form a texture or LOGO pattern, and then the exposed glass area is etched, and finally a functional film is laminated. Although the lithography step is omitted, there are still significant problems:

[0010] Limited resolution: The screen printing accuracy is relatively low (usually >50μm), and it is difficult to achieve fine LOGOs or complex gradient textures, affecting the appearance performance of high-end products.

[0011] Adhesion defect: The adhesion between the ink and the glass is greatly affected by the environmental temperature and humidity. During etching, edge erosion or ink peeling is likely to occur, resulting in blurred or incomplete patterns.

[0012] Environmental protection pressure: Screen printing inks contain volatile organic compounds (VOCs), and additional environmental protection costs are required for the treatment of etching waste liquid.

[0013] 3. Common technical bottlenecks

[0014] Lamination process defect: The existing optical film and the etched glass surface need to be laminated through glue, which is prone to air bubbles and warping. Especially on curved glass, the lamination yield is less than 70%.

[0015] Inability to balance efficiency and precision: High-precision patterns rely on exposure and development, but the cost is high; screen printing has a lower cost but cannot meet the high-resolution requirements, and manufacturers face a dilemma.

[0016] In summary, the existing technologies seriously restrict the mass production economy and quality consistency of curved glass LOGO / textures due to problems such as long process chains, large material losses, and fluctuating yields. Therefore, there is an urgent need to develop a new manufacturing method with low cost, high yield, and simplified processes to break through the existing technical bottlenecks. Summary of the Invention

[0017] To solve the technical problems in the background art, the present invention proposes a method for processing a three-dimensional LOGO on a mobile phone glass cover plate, including three steps: screen printing a hollowed-out LOGO area, etching the LOGO area, and spraying a contrasting color on the LOGO area. By using the height difference and color contrast between the LOGO area and the glass surface, a three-dimensional effect is formed, significantly improving the surface decoration effect and production efficiency of the glass cover plate.

[0018] The object of the present invention can be achieved through the following technical solutions:

[0019] A method for processing a three-dimensional LOGO on a mobile phone cover plate glass, including:

[0020] Step S1, screen printing a protective ink on the surface of the glass cover plate to form a hollowed-out area for the LOGO;

[0021] Step S2, chemically etching the hollowed-out LOGO area to form a concave structure;

[0022] Step S3, spraying a contrasting color ink different from the screen-printed protective ink on the etched LOGO area to form a three-dimensional visual effect with a height difference from the surface of the glass cover plate through the concave structure.

[0023] Further, step S1 specifically includes:

[0024] Pretreatment of the glass cover plate: Use ultrasonic cleaning or alcohol wiping to remove grease, dust, and fingerprints on the surface of the glass cover plate, ensure the ink adhesion, dry the glass cover plate, and ensure that there is no water residue on the surface of the glass cover plate;

[0025] Screen printing plate making: Use a high-precision stainless steel / polyester screen printing plate, and form a hollow LOGO area after exposure and development;

[0026] Ink selection: According to the etching requirements, select acid-resistant protective ink, epoxy resin-based ink or UV-curable ink to resist the corrosion of the subsequent etching solution and ensure that it does not fall off during the etching process;

[0027] Screen printing: Place the glass cover plate on the screen printing machine table, install the squeegee on the machine table to align with the screen printing plate pattern, install the flood blade on the machine table to align with the screen printing plate pattern, add the adjusted protective ink into the screen printing plate, and start the machine for screen printing.

[0028] Further, in step S1, the LOGO area of the screen printing plate is completely hollowed out, and there is no ink coverage after screen printing. The non-LOGO area of the screen printing plate is a closed mesh hole, and the ink completely covers it after screen printing.

[0029] Further, in step S1, the shape of the hollowed-out LOGO area is larger than the actual LOGO design size to compensate for the subsequent etching diffusion effect, and the LOGO hollowed-out area is expanded by 0.05 - 0.1 mm.

[0030] Further, step S2 specifically includes:

[0031] Etching solution preparation: Mix hydrofluoric acid and deionized water according to the volume ratio, or directly use a preset concentration of ammonium fluoride solution;

[0032] Etching control: Use the prepared etching solution to chemically etch the hollowed-out LOGO area on the glass cover plate, and adjust the etching time and etching temperature according to the expected depth of the recessed structure;

[0033] Post-etching treatment: Immediately rinse the etched area with deionized water, neutralize the residual acid solution, and then dry.

[0034] Further, in step S2, the depth of the recessed structure is 0.1 - 0.8 mm, and the side wall of the recessed structure forms an inclination angle of 110 - 135° with the surface of the glass cover plate.

[0035] Further, step S3 specifically includes:

[0036] Select ink type: Use polyurethane-based or epoxy resin-based ink as the contrast color ink;

[0037] Spraying: Use a precision nozzle to perform spot spraying on the LOGO area of the glass cover plate;

[0038] Curing: Cure the contrasting color ink layer in the LOGO area by means of ultraviolet curing or thermal curing.

[0039] Further, in step S3, the thickness of the contrasting color ink layer is 15 - 30 μm, and the difference in surface gloss between the contrasting color ink layer and the glass substrate is ≤ 10%.

[0040] Further, after step S3, step S4 is continued. A nano - scale silica coating is sprayed on the surface of the LOGO area after spraying the contrasting color ink, and a protective layer with a certain hardness is formed through heat treatment.

[0041] Further, after step S4, step S5 is continued. An anti - stain coating containing fluorosilane is applied to the entire surface of the glass cover plate, including the LOGO area and the non - LOGO area.

[0042] Advantages of the present invention: The method for processing a three - dimensional LOGO on a mobile phone glass cover plate provided by the present invention first screens a protective ink on the surface of the glass cover plate to hollow out the LOGO area, then generates a concave structure in the hollowed - out LOGO area through chemical etching, and finally sprays a contrasting color ink on the LOGO area. Utilizing the height difference of the concave structure and the contrast of the two - color inks between the LOGO area and the non - LOGO area, a strong three - dimensional visual effect is produced. Through an integrated ink design, the common problem of interlayer peeling in traditional processes is avoided, and the product yield is increased by 15 - 20%. Compared with the prior art, multiple complex processes such as photoresist coating, mask exposure, developing and removing photoresist, and functional film lamination are omitted, realizing efficient production by a three - step method. The number of processes is reduced by more than 50%, significantly reducing equipment investment and process time, reducing process connection and yield loss, and significantly improving the surface decoration effect and production efficiency of the glass cover plate. Description of the Drawings

[0043] Figure 1 It is a flow chart of the present invention. Detailed Embodiments

[0044] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0045] As Figure 1 shown, the present invention provides a method for processing a three - dimensional LOGO on a mobile phone glass cover plate, specifically including the following steps:

[0046] Step S1, screen-print a protective ink on the surface of the glass cover plate to form a hollowed-out area in the LOGO area.

[0047] Step S2, chemically etch the hollowed-out LOGO area to form a sunken structure.

[0048] Step S3, spray a contrasting-color ink different from the screen-printed protective ink on the etched LOGO area to form a three-dimensional visual effect with a height difference from the surface of the glass cover plate through the sunken structure.

[0049] Step S4, spray a nano-scale silica coating on the surface of the LOGO area after spraying the contrasting-color ink, and form a protective layer with a certain hardness through heat treatment.

[0050] Step S5, coat an anti-fouling coating containing fluorosilane on the entire surface of the glass cover plate, including the LOGO area and the non-LOGO area.

[0051] Preferably, in Step S2, the hollowed-out LOGO area can be chemically etched multiple times to form a stepped multi-level sunken structure with a depth difference of 10-20 μm in the hollowed-out LOGO area, and spray the corresponding contrasting-color inks of different colors in Step S3 to achieve a 3D gradient visual effect. After the etching in Step S2 is completed, use an ultraviolet laser to perform micron-level trimming on the edge of the etched LOGO area to remove burrs.

[0052] Among them, Step S1 specifically includes:

[0053] Pretreatment of the glass cover plate: Use ultrasonic cleaning or immersion and wiping with anhydrous ethanol to remove grease, dust and fingerprints on the surface of the glass cover plate to ensure the adhesion of the ink; among them, the frequency of ultrasonic cleaning is 40-80 kHz, and the cleaning agent is a neutral pH solution. Dry the glass cover plate with hot air at 80-120 °C for 5-10 minutes to ensure that there is no moisture residue on the surface of the glass cover plate, and the roughness ≤ 0.1 μm.

[0054] Screen plate production: Use a stainless steel screen plate or a polyester screen plate with 350-500 meshes, and control the screen plate tension at 20-25 N / cm 2 , and form a hollowed-out LOGO area through ultraviolet exposure (energy 300-500 mJ / cm 2 ) and development (developer temperature 35 ± 2 °C); among them, the LOGO area of the screen plate is completely hollowed out, and there is no ink coverage after screen printing. The non-LOGO area of the screen plate is a closed mesh hole, and the ink completely covers after screen printing. The shape of the LOGO hollowed-out area is larger than the actual LOGO design size to compensate for the subsequent etching diffusion effect. The LOGO hollowed-out area expands outwards by 0.05-0.1 mm, and the edge precision error of the LOGO hollowed-out area ≤ 0.02 mm.

[0055] Ink selection: According to the etching requirements, select an acid-resistant protective ink, an epoxy resin-based ink (corrosion resistance to hydrofluoric acid ≥ 48 hours) or a UV-curable ink (hardness after curing ≥ 3H, hydrofluoric acid concentration resistance ≥ 5%) to resist the corrosion of the subsequent etching solution and ensure that it does not fall off during the etching process.

[0056] Screen printing: Place the glass cover plate on the screen printing machine table, install the squeegee on the machine table to align with the screen pattern, install the ink return knife on the machine table to align with the screen pattern, add the adjusted protective ink into the screen, and start the machine for screen printing; among them, the squeegee angle is 60 - 75°, the pressure is 0.3 - 0.5 MPa, the printing speed is 50 - 100 mm / s, and the thickness of the protective ink is 20 - 30 μm.

[0057] Among them, step S2 specifically includes:

[0058] Etching solution preparation: Mix hydrofluoric acid and deionized water in a volume ratio of 1:(3 - 5) for preparation, with a concentration of 5 - 15%, or directly use an ammonium fluoride solution with a concentration of 10 - 20%, and control the temperature at 25 - 40°C; preferably, add a corrosion inhibitor to the etching solution, and the corrosion inhibitor uses 0.5 - 1% sodium citrate or 0.1 - 0.3% sodium dodecylbenzenesulfonate to control the uniformity of the etching rate, and the edge roughness ≤ 0.2 μm.

[0059] Etching control: Chemically etch the hollowed-out LOGO area on the glass cover plate using the prepared etching solution, and adjust the etching time and etching temperature according to the expected depth of the concave structure; preferably, mask-assisted etching can be used, and the mask opening size is 0.02 - 0.05 mm smaller than the LOGO hollowed-out area; among them, the depth of the concave structure is 0.1 - 0.8 mm, 30 - 60 seconds are required for a depth of 0.1 mm, 3 - 5 minutes are required for a depth of 0.8 mm, and the etching temperature is maintained at 20 - 30°C; and, by controlling the etching solution flow rate at 0.5 - 1.5 L / min and the mask edge tension, an inclination angle of 110 - 135° is formed between the side wall of the concave structure and the surface of the glass cover plate.

[0060] Post-etching treatment: Immediately rinse the etched area with deionized water, neutralize the residual acid solution and then dry; preferably, it can be rinsed with a 5% sodium carbonate solution for 10 - 20 seconds first, and then rinsed with deionized water. Drying is carried out by nitrogen purging or low-temperature drying at 60°C.

[0061] Among them, step S3 specifically includes:

[0062] Select ink type: Use polyurethane-based or epoxy resin-based ink as the contrast color ink; among them, the color difference ΔE between the contrast color ink and the protective ink ≥ 8, and the surface gloss difference between the contrast color ink layer and the glass substrate ≤ 10%.

[0063] Spraying: Use a precision nozzle to perform spot spraying on the LOGO area of the glass cover plate; specifically, the nozzle diameter is 0.2 - 0.5 mm, the air pressure is 0.1 - 0.3 MPa, the nozzle is 10 - 15 mm away from the glass surface, and the moving speed is 0.5 - 1.2 m / s. The thickness of the contrast color ink layer is controlled to be 15 - 30 μm, and it is sprayed in 2 - 3 times to avoid sagging.

[0064] Curing: Cure the contrast color ink layer in the LOGO area by using ultraviolet curing or thermal curing; among them, the ultraviolet curing energy is 300 - 500 mJ / cm 2 , and the thermal curing temperature is maintained at 80 - 120 °C for 10 - 30 minutes.

[0065] Among them, step S4 specifically includes:

[0066] Coating material: Use nano-silica sol with a particle size of 10 - 50 nm and a solid content of 5 - 10%.

[0067] Spraying and curing: The spraying thickness is 0.5 - 2 μm, and after spraying, it is heat-treated at 150 - 200 °C for 30 minutes to form a protective layer with a hardness ≥ 6H.

[0068] Among them, step S5 specifically includes:

[0069] Coating material: Use fluorosilane, such as heptadecafluorodecyltrimethoxysilane, and the solvent is isopropanol.

[0070] Coating method: Use a spin coating method with a rotation speed of 2000 - 3000 rpm or a vacuum coating method. The coating thickness is 100 - 200 nm, and the contact angle of the anti-fouling coating ≥ 110°.

[0071] The present invention provides a processing method for a three-dimensional LOGO on a mobile phone glass cover plate that is efficient, low-cost, and has excellent three-dimensional decoration effects. First, a protective ink layer with a hollowed-out LOGO pattern is formed on the surface of the glass cover plate using screen printing technology. Then, a micron-level concave structure with controllable depth is formed in the exposed LOGO area through a precisely controlled chemical etching process. Finally, a contrast-color ink that forms a sharp contrast with the protective ink is sprayed in the etched area. This innovative process design achieves a breakthrough three-dimensional visual effect through three key elements: one is the difference in light refraction formed by the concave structure, the second is the strong color contrast of the two-color ink, and the third is the height difference between the LOGO area and the surface of the glass cover plate. The synergistic effect of the three produces a naked-eye 3D effect that is difficult to achieve with traditional processes. Compared with traditional processes, this method has significant competitive advantages: First, it eliminates multiple complex processes such as photoresist coating, mask exposure, development and removal of photoresist, and functional film lamination, streamlining the originally complex production process into 3 core steps, reducing the number of processes by more than 50%, increasing production efficiency by about 40%, and at the same time, reducing equipment investment costs by 60%, greatly lowering the production threshold. Second, the integrated ink design avoids the common interlayer peeling problem in traditional processes, increasing the product yield by 15-20%. Third, this method supports more flexible color matching and LOGO design, can meet the stringent requirements of high-end mobile phone brands for personalized appearances, and at the same time, by optimizing etching parameters and ink formulations, reduces production costs by about 35%, having significant market competitiveness.

[0072] The above content is only an example and explanation of the structure of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, as long as they do not deviate from the structure of the invention or exceed the scope defined by this claim book, they should fall within the protection scope of the present invention.

Claims

1. A method for processing a three-dimensional LOGO on a mobile phone cover glass, characterized in that: include: Step S1, screen printing protective ink on the surface of the glass cover plate to form a hollow LOGO area; Step S2, chemically etching the hollowed-out LOGO area to form a concave structure; Step S3, spraying a contrasting color ink of a different color from the silk-screen protective ink on the etched LOGO area, and forming a three-dimensional visual effect with a height difference from the surface of the glass cover plate through the concave structure.

2. The method according to claim 1, characterized in that Step S1 specifically includes: Pretreatment of the glass cover: Use ultrasonic cleaning or alcohol wiping to remove grease, dust and fingerprints on the surface of the glass cover to ensure the adhesion of the ink, and dry the glass cover to ensure that there is no moisture residue on the surface of the glass cover; Screen production: Use high-precision stainless steel / polyester screen to form a hollow LOGO area after exposure and development; Ink selection: According to the etching requirements, choose acid-resistant protective ink, epoxy resin-based ink or UV-curable ink to resist the corrosion of subsequent etching solutions and ensure that it does not fall off during the etching process; Screen printing: Place the glass cover on the screen printing machine, install the scraper on the machine to align the screen pattern, install the ink return knife on the machine to align the screen pattern, add the adjusted protective ink to the screen, and start the machine for screen printing.

3. The method according to claim 2, characterized in that In step S1, the LOGO area of ​​the screen is completely hollowed out and is not covered by ink after screen printing, and the non-LOGO area of ​​the screen is a closed mesh and is completely covered by ink after screen printing.

4. The method according to claim 3, characterized in that In step S1, the shape of the LOGO hollow area is larger than the actual LOGO design size to compensate for the subsequent etching diffusion effect, and the LOGO hollow area expands outward by 0.05-0.1mm.

5. The method according to claim 1, characterized in that Step S2 specifically includes: Etching solution preparation: Mix hydrofluoric acid and deionized water in a volume ratio, or directly use ammonium fluoride solution of a preset concentration; Etching control: Use the configured etching solution to chemically etch the hollowed-out LOGO area on the glass cover, and adjust the etching time and etching temperature according to the expected depth of the recessed structure; Post-etching treatment: Immediately rinse the etched area with deionized water to neutralize the residual acid and then dry.

6. The method according to claim 5, characterized in that In step S2, the depth of the recessed structure is 0.1-0.8 mm, and the side wall of the recessed structure forms an inclination angle of 110-135° with the surface of the glass cover plate.

7. The method according to claim 1, characterized in that Step S3 specifically includes: Choose ink type: use polyurethane-based or epoxy-based ink as contrasting ink; Spraying: Use a precision nozzle to spray the LOGO area of ​​the glass cover at a fixed point; Curing: Use UV curing or thermal curing to cure the contrasting color ink layer in the LOGO area.

8. The method according to claim 7, characterized in that In step S3, the thickness of the contrasting color ink layer is 15-30 μm, and the difference in surface glossiness of the contrasting color ink layer and the glass substrate is ≤10%.

9. The method according to claim 1, characterized in that: After step S3, step S4 is continued to be executed, in which a nano-scale silicon dioxide coating is sprayed on the surface of the LOGO area after the contrast color ink is sprayed, and a protective layer with a certain hardness is formed through heat treatment.

10. The method according to claim 9, characterized in that After step S4, step S5 is continued to be performed to coat a layer of anti-fouling coating containing fluorine silane on the entire surface of the glass cover plate, including the LOGO area and the non-LOGO area.

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