Method for masking assembly area of glass substrate coated with AF film and application thereof

Abstract

The application discloses a method for coating AF film on a glass substrate and shielding an assembling area, and applies to coating AF film on the whole surface of a glass substrate with a modified hydrosol layer printed on the assembling area, and then washing and removing the modified hydrosol on the assembling area of the glass substrate. When the modified hydrosol is printed on the glass substrate, the modified hydrosol has a good edge protection effect. The method for shielding the assembling area has the advantages of high precision, low cost, easy operation, high production capacity and high yield, and is beneficial to industrial mass production.

Description

Technical Field

[0001] This invention belongs to the field of glass processing technology, and particularly relates to a method and application for masking the assembly area of ​​a glass substrate coated with an AF film. Background Technology

[0002] Currently, coating glass surfaces with an anti-fouling and anti-fingerprint film is the most common practice to improve their resistance to stains and fingerprints. While the low surface energy of the anti-fouling and anti-fingerprint film gives it strong hydrophobicity and resistance, it also makes it difficult for subsequent assemblies to adhere firmly to its surface. Therefore, in existing technologies, to ensure that components can be firmly bonded to the anti-fouling glass substrate, a coating needs to be pre-applied to the assembly area of ​​the glass surface before the functional film is applied.

[0003] Currently, the most common method for applying a coating to the assembly area is screen printing ink. Although the ink can prevent the assembly area on the glass surface from being coated with an AF film, this method is low in precision, high in cost, and difficult to operate. In addition, laser engraving can also cause some damage to the glass substrate when removing the ink.

[0004] Therefore, this invention proposes a new process to solve the problem of shielding the assembly area. Summary of the Invention

[0005] To address the technical problems existing in the background art, the present invention proposes a solution.

[0006] The present invention provides a method for masking the assembly area of ​​a glass substrate coated with an AF film, comprising the following steps:

[0007] S1. Screen print modified hydrosol on the assembly area of ​​the glass substrate and cure it;

[0008] S2. After screen printing the hydrosol in step S1, deposit an AF film layer on the surface of the glass substrate.

[0009] S3. Remove the hydrosol from the assembly area of ​​the glass substrate coated with AF film in step S2.

[0010] Compared with existing screen printing inks, the screen printing of modified hydrosol in the assembly area has higher precision (0.01mm).

[0011] In step S1, the modified hydrosol comprises the following raw materials in parts by weight: 5-15 parts deionized water, 30-60 parts plasticizer, 0.3-0.8 parts zinc stearate, 0.3-0.8 parts calcium stearate, 0.3-0.8 parts magnesium stearate, and 40-70 parts PVC paste resin.

[0012] In this invention, stearates of appropriate types and proportions can form a continuous lubricating layer on the surface of PVC molecular chains, thereby increasing the fluidity of the modified hydrosol.

[0013] The modified hydrosol is prepared by the following steps: the raw materials are mixed in the following order: deionized water, plasticizer, zinc stearate, calcium stearate, magnesium stearate and PVC paste resin.

[0014] Preferably, the mixing temperature is 50-70°C;

[0015] Preferably, the mixing method is stirring, and the stirring speed is 100-600 r / min.

[0016] The preparation of the modified hydrosol also includes a condensation reaction of zinc stearate, calcium stearate and magnesium stearate with a silane coupling agent.

[0017] Preferably, the condensation reaction is carried out by hydrolyzing the silane coupling agent and then condensing it with zinc stearate, calcium stearate and magnesium stearate.

[0018] In this invention, the stearate in the modified hydrosol can produce a certain lubricating effect. However, when the adhesive is stored for a long time, the presence of water in the system will weaken the bond between the stearate and the PVC molecular chain, and damage the integrity of the lubricating layer. After the stearate and the silane coupling agent undergo a condensation reaction, they can form a continuous and stable lubricating layer on the surface of the PVC molecular chain. This not only increases the storage time of the adhesive, but also makes it less likely to produce jagged printing edges when the modified hydrosol is screen-printed on the surface of the glass substrate, thus producing a better edge protection effect.

[0019] Silane coupling agents possess both organic and hydrolyzable groups. The hydrolyzable groups (alkoxy, acetoxy, chloro groups) of the silane coupling agent hydrolyze to produce silanols. On one hand, the hydroxyl groups (-OH) in the silanol undergo a condensation reaction with the hydrogen atoms on the carboxyl groups of stearate, removing one water molecule to form a structure similar to -Si-OC(=O)-R (where R is the carbon chain portion of stearic acid). In this way, the silane coupling agent is chemically bonded to the stearate. On the other hand, the silanol chemically bonds to the chlorine atoms on the PVC molecular chain, thereby allowing the stearate to bond through silicon... The silane coupling agent adsorbs onto the surface of the PVC molecular chain, and the long-chain fatty acid structure of stearate forms a continuous and stable lubricating layer on the PVC molecule surface, synergistically enhancing the lubrication effect and improving the fluidity of the hydrosol. Due to the special structure of the long-chain fatty acid of stearate, it can act like a "molecular spring" during the lubrication process. Therefore, the lubricating layer formed by the silane coupling agent and stearate can also adapt to external forces through a certain degree of twisting and sliding, preventing the PVC molecular chains from getting close and entangled, reducing the internal friction of the system, and further improving the fluidity of the hydrosol.

[0020] In step 1, the thickness of the modified hydrosol screen-printed on the assembly area is 8-100 μm, the curing temperature of the modified hydrosol is 60-100℃, and the curing time is 20-50 min.

[0021] In step S2, the thickness of the AF film layer on the glass substrate is 5-80 μm.

[0022] In step S3, the hydrosol in the assembly area is removed by a brush-type cleaning machine, which requires a cleaning medium at 40-60°C to remove the hydrosol.

[0023] The cleaning medium is one of a neutral cleaning agent, ethanol, or an aqueous solution of isopropanol;

[0024] Preferably, the cleaning medium is an aqueous solution of a neutral cleaning agent;

[0025] Preferably, the cleaning time is 2-20 minutes.

[0026] In this invention, under the dual action of heating and cleaning media, the modified hydrosol layer will swell and loosen its phase interface with the glass substrate, so that the adhesive layer is removed while the AF film remains unaffected.

[0027] This invention also proposes the application of a method for shielding the assembly area of ​​a glass substrate coated with an AF film in the back cover of a mobile phone.

[0028] The mobile phone glass cover is one of a glossy surface, an AG surface, or a combination of glossy and matte surfaces;

[0029] Preferably, the thickness of the mobile phone glass back cover is 0.1-2mm.

[0030] The beneficial effects of this invention are:

[0031] (1) The screen printing of modified hydrosol in the assembly area has high precision (0.01mm), fast speed (50 pieces / minute), easy removal and high yield.

[0032] (2) Compared to screen printing ink in the assembly area and then laser engraving to remove part of the ink thickness, the process is simpler and suitable for industrial production.

[0033] (3) In the modified hydrosol, a continuous and stable lubricating layer is formed on the surface of the PVC molecular chain, which not only improves the fluidity of the modified hydrosol, but also increases the storage time of the modified hydrosol. Attached Figure Description

[0034] Figure 1 The glossy glass substrate after screen printing with hydrosol in Example 1;

[0035] Figure 2 The AG glass substrate with water-soluble adhesive screen-printed in Example 2 is shown. Detailed Implementation

[0036] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0038] The technical solution of the present invention will now be described more clearly and completely with reference to specific embodiments and comparative examples.

[0039] Example 1

[0040] This embodiment proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific steps are as follows:

[0041] (1) Take a smooth glass substrate with a thickness of 0.55mm. Use a flatbed cleaning machine (micro flatbed machine ZC-8456) to clean the surface of the glass substrate. The cleaning temperature is 50℃ and the cleaning time is 60S. Dry the cleaned smooth glass substrate for later use.

[0042] (2) In the assembly area of ​​the glossy glass substrate, a modified hydrosol with a thickness of 20 μm is screen-printed. The glossy glass substrate with the modified hydrosol screen-printed is dried in an oven at a temperature of 80°C for 30 min.

[0043] The modified hydrosol used in step (2) for screen printing is obtained by the following preparation method: Deionized water, PVC paste resin, trioctyl trimellitate, zinc stearate, calcium stearate and magnesium stearate are weighed according to the mass ratio of 8.1:45:45:0.6:0.6:0.7. Trioctyl trimellitate is prepared into a 20wt% ethanol solution for later use. Under the conditions of stirring speed of 150r / min and temperature of 50℃, the raw materials are added to the beaker in the order of deionized water, trioctyl trimellitate ethanol solution, zinc stearate, calcium stearate, magnesium stearate and PVC paste resin. When the PVC paste resin is completely added, the temperature is raised to 70℃, the stirring speed is increased to 600r / min, and stirring is continued for 30 minutes to obtain the hydrosol.

[0044] (3) Place the glossy glass substrate with modified hydrosol screen printed in step (2) into a coating machine and coat a 10μm thick AF film on the glass surface.

[0045] (4) Place the glass substrate coated in step (3) in the cleaning medium and clean it for 10 minutes using a brush cleaning machine to remove the modified hydrosol in the assembly area and obtain the glass substrate to be assembled. The brush bristles are made of soft nylon with a Shore hardness of 30HA. The pressure applied by the brush bristles to the glass surface is 0.1MPa, the brush speed is 50r / min, the cleaning process temperature is 50℃, and the cleaning medium is an aqueous solution of neutral cleaning agent (alkyl glycoside 5wt%, fatty alcohol polyoxyethylene ether 3wt%).

[0046] Example 2

[0047] This embodiment proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific steps are as follows:

[0048] (1) Take an AG surface glass substrate with a glass thickness of 0.50mm. Use a flatbed cleaning machine (micro flatbed machine ZC-8456) to clean the surface of the glass substrate. The cleaning temperature is 50℃ and the cleaning time is 60S. Dry the cleaned AG surface glass substrate for later use.

[0049] (2) In the assembly area of ​​the AG glass, a modified hydrosol with a thickness of 30μm is screen-printed. The AG glass substrate with the modified hydrosol screen-printed is dried in an oven at a temperature of 80℃ for 30min.

[0050] The modified hydrosol used in step (2) for screen printing is obtained by the following preparation method: Deionized water, PVC paste resin, trioctyl trimellitate, zinc stearate, calcium stearate and magnesium stearate are weighed according to the mass ratio of 14:45:40:0.3:0.4:0.3, and trioctyl trimellitate is prepared into a 20wt% solution with ethanol for later use; under the conditions of stirring speed of 150r / min and temperature of 50℃, the raw materials are added to the beaker in the order of deionized water, trioctyl trimellitate ethanol solution, zinc stearate, calcium stearate, magnesium stearate and PVC paste resin. After the PVC paste resin is completely added, the temperature is raised to 70℃, the stirring speed is increased to 500r / min, and stirring is continued for 30 minutes to obtain the hydrosol.

[0051] (3) Place the AG glass substrate with modified hydrosol screen printed in step (2) into a coating machine and coat a 20μm thick AF film on the glass surface.

[0052] (4) Place the glass substrate coated in step (3) in the cleaning medium and clean it for 10 minutes using a brush cleaning machine to remove the modified hydrosol in the assembly area and obtain the AG surface glass substrate to be assembled; the brush bristles are made of soft nylon with a Shore hardness of 30HA, the pressure applied by the brush bristles to the glass surface is 0.1MPa, the brush speed is 50r / min, the cleaning temperature is 50℃, and the cleaning medium is an aqueous solution of neutral cleaning agent (6wt% alkyl glycoside and 5wt% fatty alcohol polyoxyethylene ether).

[0053] Example 3

[0054] This embodiment proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific steps are as follows:

[0055] (1) Take a smooth glass substrate with a thickness of 0.55mm. Use a flatbed cleaning machine (micro flatbed machine ZC-8456) to clean the surface of the glass substrate. The cleaning process temperature is 50℃ and the cleaning time is 60S. Observe the cleanliness of the glass surface from multiple angles under strong light. Dry the cleaned glass substrate for later use.

[0056] (2) In the assembly area of ​​the glossy glass substrate, a modified hydrosol with a thickness of 20 μm is screen-printed. The glass substrate with the modified hydrosol screen-printed is dried in an oven at a temperature of 80°C for 45 min.

[0057] The modified hydrosol used in step (2) for screen printing is obtained by the following preparation method: Deionized water, PVC paste resin, trioctyl trimellitate, 3-hydroxypropyltrimethoxysilane, zinc stearate, calcium stearate and magnesium stearate are weighed according to the mass ratio of 12.5:45:40:1:0.5:0.7:0.3, and trioctyl trimellitate is prepared into a 20wt% solution with ethanol for later use; Under the conditions of stirring speed of 150r / min and temperature of 50℃, the raw materials are added to the beaker in the order of deionized water, trioctyl trimellitate ethanol solution, 3-hydroxypropyltrimethoxysilane, zinc stearate, calcium stearate, magnesium stearate and PVC paste resin. When the PVC paste resin is completely added, the temperature is raised to 70℃, the stirring speed is increased to 600r / min, and stirring is continued for 30 minutes to obtain the hydrosol;

[0058] (3) Place the glossy glass substrate with modified hydrosol screen printed in step (2) into a coating machine and coat a 10μm thick AF film on the glass surface.

[0059] (4) Place the coated smooth glass substrate from step (3) in the cleaning medium and clean it for 10 minutes using a brush cleaning machine to remove the modified hydrosol from the assembly area and obtain the smooth glass substrate to be assembled. The brush bristles are made of soft nylon with a Shore hardness of 30HA. The pressure applied by the brush bristles to the glass surface is 0.1MPa, the brush speed is 50r / min, the cleaning temperature is 50℃, and the cleaning medium is an aqueous solution of neutral cleaning agent (alkyl glycoside 5wt%, fatty alcohol polyoxyethylene ether 3wt%).

[0060] Example 4

[0061] This embodiment proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific steps are as follows:

[0062] (1) Take an AG surface glass substrate with a glass thickness of 0.50mm. Use a flatbed cleaning machine (micro flatbed machine ZC-8456) to clean the surface of the glass substrate. The cleaning process temperature is 50℃ and the cleaning time is 60S. Dry the cleaned glass substrate for later use.

[0063] (2) In the assembly area of ​​the AG surface glass substrate, a water-soluble adhesive with a thickness of 20 μm is screen-printed. The glass substrate with the modified water-soluble adhesive screen-printed is dried in an oven at a temperature of 80°C for 45 min.

[0064] The modified hydrosol used in step (2) for screen printing is prepared as follows: Deionized water, PVC paste resin, trioctyl trimellitate, 3-hydroxypropyltriethoxysilane, zinc stearate, calcium stearate and magnesium stearate are weighed according to the mass ratio of 9:47:41:1.5:0.5:0.7:0.3, and trioctyl trimellitate is prepared into a 20wt% solution with ethanol for later use; Under the conditions of stirring speed of 150r / min and temperature of 50℃, the raw materials are added to the beaker in the order of deionized water, trioctyl trimellitate ethanol solution, 3-hydroxypropyltriethoxysilane, zinc stearate, calcium stearate, magnesium stearate and PVC paste resin. When the PVC paste resin is completely added, the temperature is raised to 70℃, the stirring speed is increased to 600r / min, and stirring is continued for 30 minutes to obtain the hydrosol;

[0065] (3) Place the AG glass substrate with modified hydrosol screen printed in step (2) into a coating machine and coat a 10μm thick AF film on the glass surface.

[0066] (4) Place the AG glass substrate coated in step (3) in the cleaning medium and clean it for 10 minutes using a brush cleaning machine to remove the water-soluble adhesive in the assembly area to obtain the glass substrate to be assembled. The brush bristles are made of soft nylon with a Shore hardness of 30HA. The pressure applied by the brush bristles to the glass surface is 0.1MPa, the brush speed is 50r / min, the cleaning temperature is 50℃, and the cleaning medium is an aqueous solution of neutral cleaning agent (7wt% alkyl glycoside and 2wt% fatty alcohol polyoxyethylene ether).

[0067] like Figure 1 As shown, point 1 is the assembly area of ​​the glossy glass in Example 1, used for screen printing modified water-soluble adhesive; as Figure 2 As shown, point 1 is the assembly area of ​​the AG surface glass in Example 2, which is used for screen printing modified water-soluble adhesive.

[0068] Comparative Example 1

[0069] This comparative example proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific steps are as follows:

[0070] (1) Take a smooth glass substrate with a thickness of 0.55mm. Use a flatbed cleaning machine (micro flatbed machine ZC-8456) to clean the surface of the glass substrate. The cleaning process temperature is 50℃ and the cleaning time is 60S. Dry the cleaned glass substrate for later use.

[0071] (2) In the assembly area of ​​the glossy glass substrate, ink with a thickness of 20μm is screen printed. The glass substrate with screen printed ink is dried in an oven at a temperature of 80℃ for 30min.

[0072] In step (2), the ink used for screen printing is composed of 50% epoxy resin, 10% iron oxide, 0.3% defoamer, 9.7% plasticizer, and 30% methyl ethyl ketone.

[0073] (3) Place the glass substrate with ink screen printed in step (2) into a coating machine and coat a 10μm thick AF film on the glass surface.

[0074] (4) Remove some of the ink from the glass substrate coated with AF film in step (3) using an ultraviolet laser engraving device to obtain the glass substrate to be assembled. The laser power is 0.95W, the speed is 350mm / s, and the frequency is 30khz.

[0075] Comparative Example 2

[0076] This comparative example proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific steps are the same as those in Example 1, except that magnesium stearate is omitted in the preparation of the hydrosol in step (2).

[0077] Comparative Example 3

[0078] This comparative example proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific operation steps are the same as those in Example 3, except that the mass ratio of the hydrosol components in step (2) is changed from "12.5:45:40:1:0.5:0.7:0.3" to "12.5:45:40:5:0.5:0.7:0.3".

[0079] Comparative Example 4

[0080] This comparative example proposes a method for masking the assembly area of ​​a glass substrate coated with an AF film. The specific operation steps are the same as those in Example 3, except that the mass ratio of the components of the hydrosol in step (2) is changed from "12.5:45:40:1:0.5:0.7:0.3" to "12.5:45:40:1:0.2:0.1:1.2".

[0081] Adhesion performance test

[0082] In the following adhesive performance test, the components were replaced with polycarbonate plastic blocks of the same size.

[0083] Take the glass substrates to be assembled from the above embodiments and comparative examples, coat the assembly area of ​​these glass substrates with epoxy resin adhesive, align the polycarbonate plastic blocks of the same size with the area coated with adhesive, press gently to remove air bubbles, and make the adhesive evenly distributed on the bonding interface. Place the bonded samples in an oven, cure at 80°C for 2 hours, and test the bonding strength on a universal testing machine (Meters CMT4104). The bonding strength is calculated and the test results are shown in Table 1.

[0084] Table 1. Results of the bonding performance tests of assembled glass in each embodiment and comparative example.

[0085] sample Bond strength (MPa) Yield % Example 1 3.27 96.2 Example 2 3.58 95.5 Example 3 5.19 95.6 Example 4 5.22 96.7 Comparative Example 1 1.89 88.3 Comparative Example 2 2.43 95.8 Comparative Example 3 2.79 96.1 Comparative Example 4 2.63 95.4

[0086] As shown in Table 1, in Examples 1-4, the addition of appropriate types and proportions of stearates to the hydrosol improved its fluidity, resulting in a high precision of 0.01 mm for the hydrosol screen-printed on the glass cover, which is far superior to the precision of laser removal achieved by existing screen-printing inks. In particular, in Examples 3 and 4, the addition of silane coupling agents further reduced the internal friction of the hydrosol, resulting in very smooth printing edges and good edge protection when printed on the glass cover, making it less likely for components in the assembly area to fall off. In contrast, Comparative Examples 1-4 did not form a smooth and continuous lubricating layer, leading to poorer fluidity of the hydrosol and making it easier for the plastic blocks tested in the assembly area to fall off.

[0087] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for masking the assembly area of ​​a glass substrate coated with an AF film, characterized in that, Includes the following steps: S1. Screen print modified hydrosol on the assembly area of ​​the glass substrate and cure it; S2. After screen printing the hydrosol in step S1, deposit an AF film layer on the surface of the glass substrate. S3. Remove the modified hydrosol from the glass substrate assembly area in step S2; In step S1, the modified hydrosol comprises the following raw materials in parts by weight: 5-15 parts deionized water, 30-60 parts plasticizer, 0.3-0.8 parts zinc stearate, 0.3-0.8 parts calcium stearate, 0.3-0.8 parts magnesium stearate, and 40-70 parts PVC paste resin. The modified hydrosol is prepared by the following steps: the raw materials are mixed in the following order: deionized water, plasticizer, zinc stearate, calcium stearate, magnesium stearate and PVC paste resin. The mixing temperature is 50-70℃; The mixing method is stirring, and the stirring speed is 100-600 r / min; The preparation of the modified hydrosol also includes a condensation reaction of zinc stearate, calcium stearate and magnesium stearate with a silane coupling agent. The condensation reaction is achieved by hydrolyzing the silane coupling agent and then condensing it with zinc stearate, calcium stearate and magnesium stearate. The silane coupling agent is 3-hydroxypropyltrimethoxysilane, and the amount of 3-hydroxypropyltrimethoxysilane used is 1-1.5 parts by weight per 100 parts by weight of modified hydrosol.

2. The method for shielding the assembly area of ​​the glass substrate coated with AF film according to claim 1, characterized in that, In step 1, the thickness of the modified hydrosol screen-printed on the assembly area is 8-100 μm, the curing temperature of the modified hydrosol is 60-100℃, and the curing time is 20-50 min.

3. The method for shielding the assembly area of ​​the glass substrate coated with AF film according to claim 1 or 2, characterized in that, In step S2, the thickness of the AF film layer on the glass substrate is 5-80 μm.

4. The method for shielding the assembly area of ​​a glass substrate coated with an AF film according to claim 1, characterized in that, In step S3, the hydrosol in the assembly area is removed by a brush-type cleaning machine, which requires a cleaning medium at 40-60°C to remove the hydrosol.

5. The method for shielding the assembly area of ​​the glass substrate coated with AF film according to claim 4, characterized in that, The cleaning medium is one of a neutral cleaning agent, ethanol, or an aqueous solution of isopropanol.

6. The method for shielding the assembly area of ​​the glass substrate coated with AF film according to claim 5, characterized in that, The cleaning medium is an aqueous solution of a neutral cleaning agent.

7. The method for shielding the assembly area of ​​a glass substrate coated with an AF film according to claim 5 or 6, characterized in that, The cleaning time is 2-20 minutes.

8. The application of the method for shielding the assembly area of ​​the glass substrate coated with AF film according to any one of claims 1-7 in the back cover of a mobile phone glass.

9. The application of the method for shielding the assembly area of ​​the glass substrate coated with AF film according to claim 8 in the back cover of a mobile phone glass, characterized in that, The mobile phone glass cover is one of a glossy surface, an AG surface, or a combination of glossy and matte surfaces; The thickness of the mobile phone glass back cover is 0.1-2mm.

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