Method for splicing tempered glass and PC plastic glass

Abstract

The application provides a laminating method of tempered glass and PC plastic glass, and relates to the technical field of composite glass processing. The PC plastic glass is subjected to constrained annealing, and the surfaces to be laminated of the tempered glass and the PC plastic glass are subjected to differential activation respectively. A transparent TPU film with exhaust microgrooves is arranged between the two, and an exhaust strip can be pulled away is arranged on the periphery. The laminating is completed after first vacuum pre-laminating, vacuum extraction of the exhaust strip, second vacuum edge sealing and low-temperature pressurizing treatment. Through the synergistic control of PC constrained annealing, differential interface activation of the tempered glass and the PC plastic glass, microgroove gas guiding and periphery delayed sealing, the application realizes the interface air exhaust, residual stress release and reliable bonding of heterogeneous materials, and has good application prospect in the fields of building, vehicle and safety protection transparent components.

Description

Technical Field

[0001] This invention relates to the field of composite glass processing technology, and more particularly to a method for laminating tempered glass and PC plastic glass. Background Technology

[0002] Tempered glass has high surface hardness, wear resistance, and weather resistance, while PC plastic glass is lightweight, has high impact resistance, and does not easily shatter into sharp fragments after breakage. Combining the two provides both surface protection and impact energy absorption, making it suitable for building doors and windows, vehicle transparent components, protective partitions, and equipment observation windows.

[0003] However, tempered glass differs significantly from PC plastic glass in terms of thermal expansion coefficient, hygroscopicity, surface polarity, and heat resistance. PC plastic glass may also develop residual stress and absorb moisture during extrusion, cutting, and storage. When using conventional laminated glass processes such as single-roll pressing or high-temperature, high-pressure lamination, interface bubbles, edge delamination, PC warping, and optical distortion are prone to occur.

[0004] Chinese patent application CN1690005A discloses a method for manufacturing high-strength bulletproof laminated glass, which involves placing a polycarbonate film between an adhesive film and a glass plate, and then using a low-temperature, high-pressure process to expel air. This method primarily targets multi-layer bulletproof glass and does not address the residual stress in thick PC plastic glass or the issue of premature sealing around the glass-PC perimeter.

[0005] The invention patent with publication number CN101760143A discloses a highly transparent polyurethane hot melt adhesive film that can simultaneously bond inorganic glass and PC sheets, solving the problem of insufficient bonding ability between ordinary PVB and PC. However, improving the film formula alone is still insufficient to eliminate residual stress in PC, residual air at the interface, and edge stress caused by the difference in thermal expansion between the two types of sheets.

[0006] The invention patent with publication number CN122008675A discloses a multi-layer high-impact TPU glass interlayer film, which uses a core layer and a skin layer to improve the film's performance. This solution mainly targets the strength, weather resistance, and glass adhesion performance of the TPU film itself, but does not disclose the peripheral delayed sealing and constrained annealing processes when tempered glass and PC plastic glass are laminated together.

[0007] Therefore, there is a need for a lamination method that can fully expel interfacial air within the temperature range that the PC can withstand and release thermal expansion mismatch stress before the edges are finally closed. Summary of the Invention

[0008] In view of this, the present invention provides a method for bonding tempered glass and PC plastic glass. Through the synergistic control of constrained annealing of PC, differentiated interface activation between tempered glass and PC plastic glass (PC sheet), microgroove air conduction, and peripheral delayed sealing, the present invention achieves interfacial air removal, residual stress release, and reliable bonding of dissimilar materials, showing promising application prospects in fields such as architecture, vehicles, and transparent safety protection components.

[0009] The first aspect of this invention provides a method for laminating tempered glass and PC plastic glass, comprising the following steps: S1. Clamp the PC plastic glass between two flat heat-resistant plates and perform constrained annealing at 105~120℃ for 1~3 hours to release residual molding stress and remove moisture while maintaining flatness. Then, cool it to no higher than 40℃ while maintaining flatness and constraint. S2. After plasma activation of the tempered glass to be bonded, a silane coupling agent is applied. After plasma activation of the PC plastic glass to be bonded, a water-based aliphatic polyurethane primer is applied. The surface tension of the tempered glass to be bonded is not less than 52 mN / m, and the surface tension of the PC plastic glass to be bonded is 42~48 mN / m. S3. A transparent TPU film is placed between tempered glass and PC plastic glass. The side of the TPU film facing the PC plastic glass has interconnected venting micro-grooves, and the outlet of the venting micro-grooves extends to the peripheral area of ​​the TPU film. A removable venting strip is placed in the peripheral area between the TPU film and the PC plastic glass, so that the outlet of the venting micro-grooves is connected to the venting pattern of the removable venting strip, thus obtaining the assembly to be assembled. S4. Place the assembly to be bonded in a vacuum bag, so that the pull-out end of the removable exhaust strip extends out of the assembly and passes through the self-sealing extraction port of the vacuum bag; evacuate to a vacuum gauge pressure of -0.095 MPa to -0.085 MPa, and maintain at 70 to 80°C for 15 to 30 minutes to pre-bond the central area of ​​the assembly to be bonded, while making the peripheral area connected to the inside of the vacuum bag through the removable exhaust strip; S5. While maintaining the vacuum state inside the vacuum bag, extract the removable exhaust strip from the peripheral area of ​​the assembly to be assembled along the predetermined extraction direction, and then continue vacuum treatment at 90~105℃ for 30~60 min to seal the peripheral area of ​​the assembly to be assembled. S6. After vacuum treatment, the assembly to be assembled is pressurized at 100~115℃ and 0.6~0.9 MPa for 45~90 minutes. Under the condition of maintaining pressure, it is cooled to no higher than 45℃. After depressurization, the laminated product of tempered glass and PC plastic glass is obtained.

[0010] After vacuum degassing, the present invention performs pressurization treatment at a temperature not exceeding 115°C, and cools down while maintaining pressure. This can reduce the high-temperature softening deformation of PC and the warping caused by thermal expansion differences during the cooling process.

[0011] Preferably, the tempered glass has a thickness of 3-8 mm, the PC plastic glass has a thickness of 2-6 mm, the transparent TPU film has a thickness of 0.76-1.52 mm, and the Shore A hardness is 78-88.

[0012] Preferably, in step S1, the uniform pressure applied to the PC plastic glass surface by the two flat heat-resistant plates is 0.5~2.0 kPa; after annealing, it is cooled to 80°C at a rate not exceeding 2°C / min, and then cooled to not exceeding 40°C.

[0013] Based on the difference between the hydrophilicity of tempered glass and the relative hydrophobicity of PC surface, this invention performs surface activation and primer treatment on the two types of sheets to be bonded.

[0014] Before surface activation, the tempered glass and PC board surfaces to be bonded are cleaned with a neutral water-based cleaning agent and deionized water, respectively, and then dried with clean nitrogen gas. The cleaned surfaces must not be touched directly by hand.

[0015] Preferably, in step S2, the tempered glass surfaces to be joined are subjected to plasma treatment, coated with an aqueous solution of γ-aminopropyltriethoxysilane at a mass fraction of 0.3%~0.8%, and dried at 60~80℃ for 10~20 min; the PC plastic glass surfaces to be joined are subjected to plasma treatment at a concentration of 1~3 g / m 2 A water-based aliphatic polyurethane primer is applied and dried at 55-70°C for 10-20 minutes. The thickness of the primer layer after drying is 0.3-1.0 μm. The primer contains 0.5%-1.5% of blocked polyisocyanate by its solid mass. The γ-aminopropyltriethoxysilane aqueous solution was prepared with deionized water, and the pH of the silane aqueous solution was adjusted to 4.5-5.0 using a 10% (w / w) acetic acid aqueous solution. The aqueous aliphatic polyurethane primer uses an aqueous aliphatic polyether polyurethane dispersion as the film-forming substance, with a solid content of 28%~32%, a viscosity of 100~300 mPa·s at 25℃, and a pH of 7.5~8.5; the blocked polyisocyanate is a low-temperature unblocking HDI polyisocyanate, with an unblocking temperature not exceeding 100℃, and the addition amount is 0.5%~1.5% of the solid mass of the primer.

[0016] Preferably, the plasma treatment is carried out using a low-pressure oxygen plasma treatment device, with the working gas being oxygen with a purity of not less than 99.5%, the treatment chamber pressure being 40~80 Pa, and the oxygen flow rate being 30~60 sccm; when treating the tempered glass to be bonded, the plasma power is 80~120 W, and the treatment time is 45~90 s; when treating the PC board to be bonded, the plasma power is 20~50 W, and the treatment time is 15~40 s; the treatment power and treatment time for the PC board are lower than those for the tempered glass to avoid excessive etching of the PC board surface or degradation of optical performance.

[0017] Preferably, within 10 minutes after plasma treatment, the wetting tension of the surfaces to be bonded is determined using a graded wetting tension test solution, referring to GB / T 14216-2008. The ambient temperature is 23±2℃ and the relative humidity is 50%±5%. The criterion for passing is that the continuous liquid film formed by the test solution does not shrink or break significantly within 2 seconds. The wetting tension of the tempered glass surfaces to be bonded should not be less than 52 mN / m, and the wetting tension of the PC board surfaces to be bonded should be 42~48 mN / m. After the surface treatment is qualified, the primer coating should be completed within 30 minutes.

[0018] Preferably, the depth of the exhaust microgroove is 25~55 μm, the width is 150~350 μm, and the spacing between adjacent exhaust microgrooves is 8~15 mm; the exhaust microgrooves are interconnected, and the outlet of the exhaust microgroove extends to the peripheral area of ​​the TPU film and is connected to the exhaust pattern of the removable exhaust strip.

[0019] Preferably, the removable exhaust strip is made of polytetrafluoroethylene, with a width of 8~15 mm and a thickness of 0.08~0.15 mm, and its surface is provided with exhaust patterns extending along the extraction direction.

[0020] In the first vacuum process of this invention, the central area is pre-bonded, while the periphery remains connected to the external vacuum channel through an exhaust strip; after the vacuum is maintained and the exhaust strip is removed, the periphery is sealed by heating. This avoids sealing the edges first and trapping air inside the component.

[0021] Preferably, in step S4, a surface pressure of 0.02~0.08 MPa is gradually applied from the center of the assembly to be assembled to the periphery, so that air is discharged along the exhaust micro-groove and the removable exhaust strip.

[0022] Preferably, in step S6, the pressure is increased after the temperature reaches the set temperature, and after the processing is completed, the temperature is reduced while maintaining the pressure before the pressure is released.

[0023] A second aspect of the present invention provides a laminated product of tempered glass and PC plastic glass prepared by the above-described lamination method.

[0024] Compared with the prior art, the beneficial technical effects of the present invention are as follows: This invention performs constrained annealing on PC plastic glass, which can release residual stress formed during extrusion, cutting, and storage and transportation while maintaining the flatness of the sheet, and reduces the possibility of residual moisture forming bubbles during subsequent hot pressing.

[0025] This invention employs different activation and primer coating methods for tempered glass and PC plastic glass, enabling the two surfaces with different properties to form compatible interfaces with the TPU film, thus avoiding the situation where one side is fully bonded while the other side is insufficiently bonded when the same treatment method is used.

[0026] The venting micro-grooves and removable venting strips together form an venting channel extending from the inside of the component to the external vacuum space. Pre-bonding the center and then removing the peripheral venting strips delays edge sealing, allowing residual air and in-plane displacement caused by thermal expansion mismatch to be released before final edge sealing.

[0027] Low-temperature graded vacuum hot pressing can prevent PC plastic glass from being exposed to excessively high temperatures for a long time, and limit interlayer slippage and cooling warping through pressurized cooling, thereby taking into account interface adhesion, appearance quality and dimensional stability. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] Unless otherwise specified, colorless tempered glass, double-sided hardened transparent PC plastic glass, and aliphatic polyether TPU film were used; each embodiment was conducted in a clean assembly room with a temperature of 22~25℃ and a relative humidity not exceeding 35%; each embodiment was conducted in a clean assembly room with a temperature of 25℃ and a relative humidity not exceeding 35%; all tests were repeated 3 times, and the results are expressed as average values.

[0030] Example 1 The system uses 5 mm thick colorless sodium-calcium-silicon tempered glass, 4 mm thick optical-grade transparent bisphenol A extruded PC sheet, and 1.14 mm thick aliphatic polyether transparent TPU film. The PC sheet has an approximately 8 μm thick polysiloxane wear-resistant hardening layer only on the side facing away from the TPU film, and no hardening layer on the side facing the TPU film. The TPU film has a Shore A hardness of 83 and a softening temperature of 90℃. The TPU film is dried at 60℃ and a vacuum gauge pressure of -0.090 MPa for 8 h, and then sealed and cooled before use. PC plastic glass was sandwiched between two flat aluminum alloy heat-resistant plates, a uniform pressure of 1.0 kPa was applied, and it was annealed at 112℃ for 2 h, cooled to 80℃ at 1.5℃ / min, and then cooled to 35℃. The surfaces of the tempered glass and PC board to be bonded were cleaned with a neutral water-based cleaning agent and deionized water, respectively, and then dried with clean nitrogen. The tempered glass was placed in a low-pressure oxygen plasma device and treated for 60 s under conditions of 60 Pa chamber pressure, 50 sccm oxygen flow rate, and 100 W power. The PC board was placed in the same device and treated for 25 s under conditions of 60 Pa chamber pressure, 50 sccm oxygen flow rate, and 30 W power. Within 10 min after the plasma treatment, the wetting tension was measured using a wetting tension test solution. The wetting tensions of the tempered glass and PC board to be bonded were 56 mN / m and 45 mN / m, respectively. A 0.5% (w / w) aqueous solution of γ-aminopropyltriethoxysilane was coated onto the surfaces of the tempered glass to be bonded. The pH of the aqueous solution was 4.8, and it was pre-hydrolyzed for 30 min after preparation. The wet coating amount was 2 g / m². 2 The mixture was dried at 70℃ for 15 min; a water-based aliphatic polyether polyurethane primer with a solid content of 30% and a viscosity of approximately 200 mPa·s at 25℃ was applied to the surface of the PC board to be bonded, with a wet coating amount of 2 g / m². 2 The primer is dried at 62°C for 15 min. The primer contains 1.0% of its solid mass of low-temperature unblocking HDI polyisocyanate, and the unblocking temperature of the HDI polyisocyanate is not higher than 100°C. The TPU film facing the PC has a mesh exhaust micro-groove with a depth of 40 μm, a width of 240 μm, and a spacing of 11 mm. A polytetrafluoroethylene exhaust strip with a width of 10 mm and a thickness of 0.10 mm is set along the periphery between the TPU and the PC. Its extraction end passes through the self-sealing extraction port of the vacuum bag. Vacuum was applied to -0.091 MPa and held at 75°C for 22 min to pre-bond the central area. The vacuum was maintained and the exhaust strip was removed. The temperature was raised to 98°C and the process continued for 45 min. Then, pressure was applied at 108°C and 0.75 MPa for 60 min. The pressure was maintained and the product was cooled to 42°C before the pressure was released to obtain the assembled product.

[0031] Example 2 The difference from Example 1 is that the thicknesses of the tempered glass, PC, and TPU film are 3 mm, 2 mm, and 0.76 mm, respectively; the PC is annealed at 0.5 kPa constraint pressure and 105°C for 3 h; the depth, width, and spacing of the microgrooves are 25 μm, 150 μm, and 8 mm, respectively; the width and thickness of the exhaust strip are 8 mm and 0.08 mm, respectively; the first vacuum treatment is at 70°C for 30 min, the second vacuum treatment is at 90°C for 60 min; and finally, it is treated at 100°C and 0.9 MPa for 90 min.

[0032] Example 3 The difference from Example 1 is as follows: the thicknesses of the tempered glass, PC, and TPU film are 8 mm, 6 mm, and 1.52 mm, respectively; the PC is annealed at 2.0 kPa constraint pressure and 120°C for 1 h; the depth, width, and spacing of the microgrooves are 55 μm, 350 μm, and 15 mm, respectively; the width and thickness of the exhaust strip are 15 mm and 0.15 mm, respectively; the first vacuum treatment is at 80°C for 15 min, the second vacuum treatment is at 105°C for 30 min; and finally, it is treated at 115°C and 0.6 MPa for 45 min.

[0033] Comparative Example 1 The difference from Example 1 is that the PC plastic glass is not subjected to constrained annealing.

[0034] Comparative Example 2 The difference from Example 1 is that plasma activation is not performed, and the aqueous silane solution and water-based polyurethane primer are not applied.

[0035] Comparative Example 3 The difference from Example 1 is that the TPU film surface does not have exhaust microgrooves.

[0036] Comparative Example 4 The difference from Example 1 is that no removable exhaust strip is provided, and a vacuum treatment is performed directly at 98°C for 67 minutes.

[0037] Comparative Example 5 The difference from Example 1 is that the final pressurization temperature is 130°C.

[0038] Comparative Example 6 The difference from Example 1 is that: no two vacuum treatments are performed, and the final pressurization treatment is performed directly after the assembly of the composite assembly.

[0039] Performance testing Light transmittance and haze were tested in accordance with GB / T 2410-2008.

[0040] The bubble area ratio is determined using orthographic projection image analysis, and is expressed as the ratio of the bubble projection area to the effective composite area.

[0041] Peel strength was tested according to GB / T 2790-1995, with 180° peels performed on the glass-TPU interface and the PC-TPU interface respectively.

[0042] The damp heat resistance test conditions were 85℃, 85% relative humidity, and 500 h.

[0043] The temperature cycling conditions were -30℃ for 1 hour, then raised to 80℃ and held for 1 hour, for a total of 100 cycles.

[0044] Warpage is the ratio of the maximum height of the specimen from the surface to the length of the specimen, and the unit is mm / m.

[0045] Table 1 Initial performance test results

[0046] Table 2 Durability test results

[0047] As can be seen from Tables 1 and 2, constrained annealing of PC mainly improves dimensional stability and PC side bonding, differential interface activation mainly improves the bonding strength on both sides and resistance to damp heat, venting microgrooves and removable venting strips mainly reduce bubbles and edge delamination, and low-temperature pressurized cooling mainly controls PC warpage.

[0048] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for laminating tempered glass and PC plastic glass, characterized in that, Includes the following steps: S1. Clamp the PC plastic glass between two flat heat-resistant plates and perform constrained annealing at 105~120℃ for 1~3 h, and then cool it to no higher than 40℃ while maintaining flatness and constraint. S2. After plasma activation of the tempered glass to be bonded, a silane coupling agent is applied. After plasma activation of the PC plastic glass to be bonded, a water-based aliphatic polyurethane primer is applied. The surface tension of the tempered glass to be bonded is not less than 52 mN / m, and the surface tension of the PC plastic glass to be bonded is 42~48 mN / m. S3. A transparent TPU film is placed between tempered glass and PC plastic glass. The side of the TPU film facing the PC plastic glass has interconnected venting micro-grooves, and the outlet of the venting micro-grooves extends to the peripheral area of ​​the TPU film. A removable venting strip is placed in the peripheral area between the TPU film and the PC plastic glass, so that the outlet of the venting micro-grooves is connected to the venting pattern of the removable venting strip, thus obtaining the assembly to be assembled. S4. Place the assembly to be bonded in a vacuum bag, so that the pull-out end of the removable exhaust strip extends out of the assembly and passes through the self-sealing extraction port of the vacuum bag; evacuate to a vacuum gauge pressure of -0.095 MPa to -0.085 MPa, and maintain at 70 to 80°C for 15 to 30 minutes to pre-bond the central area of ​​the assembly to be bonded, while making the peripheral area connected to the inside of the vacuum bag through the removable exhaust strip; S5. While maintaining the vacuum state inside the vacuum bag, extract the removable exhaust strip from the peripheral area of ​​the assembly to be assembled along the predetermined extraction direction, and then continue vacuum treatment at 90~105℃ for 30~60 min to seal the peripheral area of ​​the assembly to be assembled. S6. After vacuum treatment, the assembly to be assembled is pressurized at 100~115℃ and 0.6~0.9 MPa for 45~90 min. Under the condition of maintaining pressure, it is cooled to no higher than 45℃. After depressurization, the laminated product of tempered glass and PC plastic glass is obtained.

2. The lamination method according to claim 1, characterized in that, The tempered glass has a thickness of 3-8 mm, the PC plastic glass has a thickness of 2-6 mm, the transparent TPU film has a thickness of 0.76-1.52 mm, and the Shore A hardness is 78-88.

3. The lamination method according to claim 1, characterized in that, In step S1, the uniform pressure applied to the PC plastic glass surface by the two flat heat-resistant plates is 0.5~2.0 kPa; after annealing, it is cooled to 80°C at a rate not exceeding 2°C / min, and then cooled to 40°C.

4. The lamination method according to claim 1, characterized in that, In step S2, the tempered glass surfaces to be joined are subjected to plasma treatment, coated with an aqueous solution of γ-aminopropyltriethoxysilane at a mass fraction of 0.3%~0.8%, and dried at 60~80℃ for 10~20 min; the PC plastic glass surfaces to be joined are subjected to plasma treatment at a concentration of 1~3 g / m 2 A water-based aliphatic polyurethane primer is applied and dried at 55-70°C for 10-20 minutes. The primer contains 0.5%-1.5% of blocked polyisocyanate by its solid mass.

5. The lamination method according to claim 1, characterized in that, The depth of the exhaust micro-groove is 25~55 μm, the width is 150~350 μm, and the spacing between adjacent exhaust micro-grooves is 8~15 mm; the exhaust micro-grooves are interconnected, and the outlet of the exhaust micro-groove extends to the peripheral area of ​​the TPU film and is connected to the exhaust texture of the removable exhaust strip.

6. The lamination method according to claim 1, characterized in that, The removable exhaust strip is made of polytetrafluoroethylene, with a width of 8~15 mm and a thickness of 0.08~0.15 mm, and its surface is provided with exhaust patterns extending along the extraction direction.

7. The lamination method according to claim 1, characterized in that, In step S4, a surface pressure of 0.02~0.08 MPa is gradually applied from the center of the assembly to be assembled to the periphery, so that air is discharged along the exhaust micro-groove and the removable exhaust strip.

8. The lamination method according to claim 1, characterized in that, In step S6, the pressure is increased after the temperature reaches the set temperature. After the process is completed, the temperature is reduced while maintaining the pressure, and then the pressure is released.

9. A composite product of tempered glass and PC plastic glass, characterized in that, The composite material comprises tempered glass, transparent TPU film, and PC plastic glass stacked sequentially, and the composite product is prepared by the lamination method according to any one of claims 1 to 8.

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