Transfer paper for display screen production and preparation process thereof

Abstract

The invention relates to the technical field of display screen production, and discloses transfer paper for display screen production and a preparation process thereof.The transfer paper for display screen production comprises a metal base material, functional silica gel layers are arranged on the upper side and the lower side of the metal base material correspondingly, release films are arranged outside the functional silica gel layers, and the functional silica gel layers are arranged on the release films. The functional silica gel layer comprises the following components in parts by weight: 70-85 parts of methyl vinyl silicone rubber; 3-7 parts of hydrogenated castor oil; 2-6 parts of an ionic liquid; 0.2 to 0.6 part of a multi-walled carbon nanotube; 0.05 to 0.2 part of a platinum catalyst; and 0.1 to 0.5 part of a fluorosilicone interfacial agent. Functional silica gel layers with different viscidity are constructed on the two sides of the metal base material, the upper layer with strong viscidity is used for fixing, the lower layer with weak viscidity is used for operation, the structure brings a major breakthrough in the automatic operation process, and clear function division of fixing and transferring in production is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of display screen production, and in particular to transfer paper for display screen production and a preparation process thereof. Background Art

[0002] In the field of modern electronic product manufacturing, especially in the production and assembly of display screens, the cleanliness and integrity of component surfaces are crucial. For example, core optical components such as polarizers and light guide plates are covered with protective films when they leave the factory to prevent scratches or contamination. Before entering the next process, precise and non-destructive removal of these protective films is a necessary step.

[0003] To meet the demand for automated peeling, some transfer tools based on silicone rubber materials have appeared in the existing technology. These tools utilize the excellent properties of silicone rubber materials themselves. Silicone rubber has good chemical inertness and flexibility. After contacting and peeling with the protective film, it will not cause chemical transfer of adhesives like traditional tapes, which can ensure that the peeled surface is clean and free of residue. At the same time, the material has a certain degree of resilience and recoverability, allowing it to be reused to a certain extent. Compared with disposable tape solutions, it has improvements in cost and environmental protection.

[0004] However, when the existing technology is deeply applied to large-scale, high-precision automated production lines, its inherent defects are exposed. First, these tools generally adopt a single-sided or uniformly sticky structure, which has inherent deficiencies in mechanical control. Automated equipment cannot independently and firmly pre-fix them. During operation, it is very easy to encounter a chaotic situation where the peeling force is greater than the tool's own fixing force, resulting in inaccurate positioning or even process failure. Secondly, standard silicone rubber is an excellent insulator. During the high-speed peeling process, a large amount of static electricity will be generated and accumulated, which is a fatal threat to the static-sensitive display panel drive circuit. At the same time, its internal structure lacks reinforcement and cannot withstand high-frequency mechanical stress, resulting in rapid viscosity decay and extremely limited service life. Finally, its physical interface also has major hidden dangers: the silicone layer and the base are connected only by weak adhesive force, which is very easy to delaminate and fall off under repeated pulling. Moreover, the flat silicone surface will trap air when it is attached, forming a large number of bubbles, which not only affects the effective peeling area, but also causes uneven stress, leading to the tearing of the protective film, seriously affecting the product yield. To this end, those skilled in the art have proposed transfer paper for display production and its preparation process to solve the above problems. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides transfer paper for display screen production and its preparation process, which solves the technical problems of transfer tools in the existing technology, such as poor automation controllability, easy generation of static electricity, short cycle life, weak interface bonding force, and easy generation of bubbles during lamination.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: transfer paper for display screen production includes a metal substrate, a functional silicone layer is provided on the upper and lower sides of the metal substrate, a release film is provided on the outside of the functional silicone layer, and the functional silicone layer includes the following components in parts by weight: Methyl vinyl silicone rubber: 70-85 parts; Hydrogenated castor oil: 3-7 parts; Ionic liquid: 2-6 parts; Multi-walled carbon nanotubes: 0.2-0.6 parts; Platinum catalyst: 0.05-0.2 parts; Fluorosilicone surfactant: 0.1-0.5 parts.

[0007] This technical solution, by constructing a metal substrate as the middle layer and a functional silicone layer on each side, achieves bidirectionally controllable adhesion performance during transfer paper use. This structure differs significantly from traditional single-sided adhesion, offering significant advantages such as a clear sequence of adhesion and separation, a distinct adhesion and separation interface, and ease of operation.

[0008] In actual use, the release film on the upper surface is first removed to expose the upper functional silicone layer. Because the upper functional silicone layer is a strong silicone layer with higher adhesion, it can ensure that the transfer paper adheres firmly to the film removal equipment, positioning device, or transfer head, thereby maintaining a stable reference position during operation. After the fixation is completed, the operator then removes the release film on the lower side, exposing the weaker silicone layer on the lower side and contacting it with the protective film or functional layer of the target display product, completing the "lifting" or "tearing" operation of the film layer.

[0009] This structural design utilizes a viscosity differential to achieve distinct functional divisions between the upper and lower sides: the upper side is responsible for fixation, while the lower side handles the transfer operation. This structurally controlled adhesion method eliminates the need for additional adhesives or energy stimulation, reduces process requirements, and improves reliability during the transfer process.

[0010] In terms of components, methyl vinyl silicone rubber is used as the main film-forming material. Its excellent flexibility, viscoelasticity and thermal stability provide a structural basis for the functional silicone layer; hydrogenated castor oil is used as a plasticizer and regulator to control the softness and recovery performance of the rubber layer after curing; ionic liquid is used as an internal regulator to improve the interaction between molecular chains, thereby further affecting the rheological properties and adhesion dynamic response of silicone; multi-walled carbon nanotubes form a supporting effect on the silicone network when added in trace amounts, thereby improving the overall microstructural stability and imparting certain shear and slip resistance; platinum catalysts are used for the addition curing reaction of silicone rubber; fluorosilicone surfactants play an important role in surface interface regulation, making the silicone layer cleaner and more complete in surface integrity when peeled off.

[0011] Preferably, the ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt; the multi-walled carbon nanotubes have a diameter of 5-15 nm, a length of 1-10 μm, and are coated with a polyvinylpyrrolidone coating; the hydrogenated castor oil has an iodine value of less than 4 and a hydroxyl value of 150-200 mgKOH / g.

[0012] This technical solution is limited by specific types and structural parameters to meet the comprehensive requirements of the functional silicone layer for viscosity, interfacial energy and mechanical response in actual use.

[0013] The selected ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, exhibits excellent thermal stability and interfacial wettability, effectively improving the compatibility of the silicone layer with the substrate interface and the surface to which the film is applied, reducing localized debonding caused by poor wetting. Furthermore, its larger anionic structure helps regulate the free volume distribution within the cross-linked network, resulting in improved low-temperature flexibility and stress-relieving properties for the silicone system.

[0014] Multi-walled carbon nanotubes (MWCNTs) coated with polyvinylpyrrolidone (PVP) significantly enhance their dispersion, preventing localized stress concentration caused by agglomeration. Controlling their size within the 5-15nm diameter and 1-10μm length range helps form a uniform microscopic skeleton network within the silicone matrix. This structure enhances the microstructural stability of the adhesive layer without compromising its adhesive and compliance properties, providing microscopic support for high-precision transfer processes.

[0015] Hydrogenated castor oil is a structurally adjustable regulating component. Its low iodine value ensures molecular chain saturation, which helps improve the aging resistance of the silicone layer. The hydroxyl value is controlled in the range of 150-200mgKOH / g, giving it good polarity matching properties. During the curing reaction, it can form micro-crosslinks with the silicone rubber chain segments, improving film uniformity and the continuity of the adhesion layer structure.

[0016] Preferably, the metal substrate is copper foil or tin foil with a thickness of 20-40 μm and a micron-scale concave-convex structure on the surface. The sawtooth depth of the concave-convex structure is 0.5-2 μm and the arrangement density is 500-800 per cm. 2 ; The functional silicone layer includes a strong silicone layer and a weak silicone layer, wherein the viscosity range of the strong silicone layer is 1000-2500mPa·s, and the viscosity range of the weak silicone layer is 600-1200mPa·s.

[0017] This technical solution, by selecting copper foil or tin foil as the intermediate substrate, ensures excellent thermal conductivity and dimensional stability while further optimizing the adhesion and interface bonding performance of the functional silicone layer by applying a micron-level concave-convex serrated structure to its surface.

[0018] The presence of the microstructure significantly increases the effective contact interface per unit area, enabling mechanical interlocking of the silicone layers at a microscopic scale during coating. This structure not only improves the bonding efficiency of the upper and lower silicone layers during hot pressing and curing, but also helps reduce the risk of interfacial tearing caused by adhesive peeling during subsequent film removal.

[0019] The core innovation of this invention in functional transfer design is the structure of strong and weak silicone layers on the upper and lower sides. By adjusting the viscosity range of the two layers, they can respectively have the functions of fixing and tearing the film, and can achieve clear step separation in production and use: When using, the operator first tears off the upper release film to expose the strong silicone layer, and then sticks it to the automatic film tearing device or positioning device to achieve stable fixation of the transfer paper as a whole; Then tear off the lower release film to make the weak silicone layer contact the surface of the target film layer. By laminating and then pulling up, the product film layer can be quickly removed.

[0020] The preparation process of transfer paper for display screen production includes the following steps: S1, surface microstructure treatment of metal substrate; S2. Preparation and mixing of functional silicone layer materials; S3, coating and heat curing treatment; S4, die-cutting and laser punching; S5, vacuum bonding and exhaust treatment; S6. Final quality inspection and packaging.

[0021] This technical solution provides a transfer paper preparation process that embodies a highly systematic and targeted multi-step process deployment, aiming to ensure efficient interfacial coupling between the functional silicone layer and the metal substrate, as well as precise control of various performance properties in actual film tearing applications.

[0022] By breaking down the process into steps, control variables such as material properties, structural interfaces, and geometric accuracy can be independently optimized at each stage. Microstructuring, as the first step, establishes the interface bonding foundation with the metal substrate, creating excellent adhesion conditions for subsequent coating and curing steps. Prefabrication and differentiated mixing of functional silicone materials lay the foundation for establishing viscosity differences between the upper and lower layers. Coating and thermal curing, through spatial control and temperature field regulation, enable simultaneous viscosity control and structural formation.

[0023] Subsequent die-cutting and perforation steps not only ensure the accuracy and repeatability of the final product's geometric contours, but also provide structural support for the functional layer's air-exhaust capacity and controllable adhesion. Finally, vacuum lamination and quality inspection further ensure the transfer paper's overall performance consistency and applicability. Each step in the entire process is interconnected, starting with the functional material, continuing through processing control and all the way to the end user, achieving a highly integrated approach from material formulation to application functionality.

[0024] Preferably, the surface microstructure treatment of the metal substrate comprises the following steps: A copper foil or tin foil with a thickness of 20-40 μm is used as a metal substrate, and a plasma etching process is used to perform microstructural treatment on its surface, so that a uniformly distributed micro-serrated structure is formed on the metal surface. The micro-serrated structure has the following characteristics: The sawtooth depth is 0.5-2μm; The aspect ratio of the saw teeth is 1:2-1:4; The arrangement is radial gradient distribution.

[0025] In this technical solution, the microstructural design of the metal substrate surface is one of the core improvements in the material interface control aspect of the invention. A plasma etching process is used to microstructure the surface of the copper or tin foil, creating a regular, zigzag pattern. This microstructure exhibits a significant interfacial anchoring effect, effectively enhancing the mechanical bond between the silicone layer and the metal substrate during the hot-press curing process without the introduction of additional chemical adhesives.

[0026] Furthermore, the "gradual distribution" strategy employed by this surface serration structure helps reduce internal stress concentration during large-area coating, allowing for the natural diffusion of interfacial stress along the film's depth, effectively preventing localized warping or interfacial voids. Furthermore, this microstructure provides microscopic stability for the secure attachment of the functional silicone layer after curing, ensuring no slippage or interfacial delamination during the transfer process, thereby maintaining the product's stability and reliability in practical applications.

[0027] Preferably, the preparation and mixing of the functional silica gel layer material includes the following steps: The components of the functional silicone layer are added to the mixing device in proportion and then uniformly mixed and vacuum degassed. The mixing conditions are as follows: strong silicone layer: mixing temperature is 30-40°C, stirring speed is 1200-1500 rpm, and mixing time is 45-60 minutes; weak silicone layer: mixing temperature is 20-30°C, stirring speed is 1000-1200 rpm, and mixing time is 30-45 minutes; then vacuum degassed, and the vacuum degree is controlled at -0.08 to -0.095 MPa.

[0028] This technical solution, during the preparation of the functional silicone layer, differentiates the mixing temperature, stirring intensity, and time of the upper (strong) and lower (weak) silicone layers, imparting essentially distinct rheological properties to the two silicone materials. This proactive process adjustment ensures that, despite being structurally homologous, the upper and lower functional silicone layers exhibit distinct differences in adhesion response, achieving functional differentiation independent of chemical formulations.

[0029] Vacuum degassing, a key process in this step, ensures that gases in the mixed adhesive are effectively removed to prevent the formation of air bubbles during curing, which can affect the adhesive layer's adhesion and continuity. This highly controlled pretreatment ensures a more uniform coating and enhances the stability of the material's properties, ensuring a strong bond between the top and bottom of the final product.

[0030] Preferably, the coating and heat curing process comprises the following steps: The obtained mixed functional silicone layer material is coated according to the coating thickness of 0.2-0.3mm for the strong silicone material and 0.1-0.2mm for the weak silicone material; After coating, hot pressing curing is carried out at a temperature of 110-130°C, the hot pressing time is 20-40 minutes, and the pressure is 0.3-0.5MPa; After curing, a release film is applied to the surface of the functional silicone layer.

[0031] This technical solution applies functional silicone materials of varying viscosities to the top and bottom surfaces of a metal substrate, combined with precise thickness control. This ensures that each layer of silicone possesses a distinct functional orientation after curing. This process creates a spatially distributed, "stronger at the top, weaker at the bottom" structure, automatically guiding the operational sequence during use: fixation first, then transfer.

[0032] The heat curing process, controlled by specific temperature and time, causes an addition reaction between the silicone molecular segments, resulting in a stable three-dimensional cross-linked network structure upon completion of the curing process. This hot-pressing process not only ensures uniform film formation of the adhesive layer but also, through pressure regulation, allows it to better embed into the substrate surface microstructure, forming a strong interfacial bond. Furthermore, the application of the release film not only provides physical protection but also facilitates the sequential peeling of the upper and lower adhesive layers during subsequent use, ensuring a clean and controllable process.

[0033] Preferably, the die cutting and laser drilling process includes the following steps: Die cutting and punching operations are performed on the solidified structural materials. The die cutting is controlled by the XY axis servo system to position and cut the die cutter. The tool pressure is 20-40N. Microhole array drilling using a pulsed laser drilling system: The positioning holes have a diameter of 0.5-1.0 mm, are closely packed in a hexagonal pattern, and have a hole spacing of 1.5-3.0 mm; The diameter of the exhaust holes is 0.1-0.3 mm, and the arrangement adopts a Fibonacci spiral structure. The density increases by 10-20% along the peeling direction, and the hole density is 150-300 holes / cm 2 ; The laser wavelength is 1064nm, the pulse width is 8-12ns, and the energy density is 2.8-3.5J / cm 2 , the focused spot diameter is 10-30μm.

[0034] In this technical solution, die-cutting and perforation design are crucial steps in enabling the transfer paper of this invention to be practically applied in automated film-tearing processes. Die-cutting ensures the dimensional consistency and boundary integrity of the structural components, while laser perforation provides the functional silicone layer with active venting and positioning capabilities.

[0035] The positioning holes are arranged in a regular geometric array to ensure accurate registration of the transfer paper during the lamination process. This not only accommodates standard tooling positioning but also compatibility with the suction mechanisms of various automated equipment. The exhaust holes are arranged in a spiral, gradually increasing density, allowing air to be gradually expelled from the bottom to the top during lamination, preventing the formation of residual bubbles. High-precision laser-controlled machining preserves the overall structure of the silicone layer while maintaining both hole position accuracy and microscopic interface integrity, ensuring the necessary conditions for subsequent vacuum lamination.

[0036] Preferably, the vacuum lamination and exhaust treatment includes the following steps: The die-cut and punched structural parts are subjected to exhaust lamination in a vacuum laminating device. The process is as follows: Vacuum degree is -0.08 to -0.1 MPa; The pulsation frequency is 3-7Hz, and the pressure difference amplitude is ±0.01MPa; The temperature of the thermal paste is controlled at 50-70°C and the processing time is 10-30 seconds; And remove the trapped air through the exhaust holes.

[0037] In this technical solution, during the vacuum lamination stage, the bonding process between the transfer paper and the target film surface is controlled through a fully sealed system, preventing external gas disturbances or particle contamination during the adhesion process. By precisely controlling the vacuum level and pressure differential pulsation frequency, the functional silicone layers adhere layer by layer during bonding, smoothly expelling the intermediate air layer and preventing the formation of interfacial bubbles.

[0038] During this process, the vents serve as structural conduction channels. Combined with a spiral arrangement and density control strategy, they allow residual gas at the bonding interface to be discharged in a stable path, thereby improving the continuity and reliability of the bonding process. Furthermore, by regulating the thermal bonding temperature, the instantaneous viscosity response of the silicone layer is further reduced, facilitating smooth bonding and rapid demolding, thereby enhancing process compatibility.

[0039] Preferably, the final quality inspection and packaging includes the following steps: The following items are fully inspected and sampled on the completed transfer paper: Dimension detection uses laser interferometry; Surface defects are identified by the AOI automatic inspection system; The electrical conductivity was tested by the four-probe resistance method; Adhesion performance was evaluated by 180° peel test for peel force; The position and aperture accuracy of the microwell array are verified by a high-magnification microscopic imaging system in conjunction with a recognition algorithm; After passing the inspection, the products will be carefully cut, packaged and cleanly packed.

[0040] In this technical solution, the quality inspection stage is the closed-loop control endpoint of the process described in the present invention. Its goal is to quantitatively confirm the key performance indicators of the transfer paper through multi-dimensional detection means to ensure that it meets the requirements of the subsequent automated film tearing process.

[0041] Laser interferometry ensures dimensional consistency and is conducive to matching with high-speed positioning systems; the AOI automatic inspection system can identify surface micro-defects and ensure the surface integrity of the functional silicone layer; the four-probe resistance test assists in evaluating the conductive stability of the metal substrate and adapts to specific electrical requirements. The peel force test and hole position accuracy test directly verify whether the structural division of the upper and lower functional layers of the present invention matches the function of the punching design.

[0042] Finally, the product is protected before leaving the factory through clean packaging, so that it will not be contaminated or its performance will be degraded during transportation and storage, thus providing guarantee for direct use by downstream customers.

[0043] In summary, this application includes at least one of the following beneficial technical effects: 1. The present invention constructs functional silicone layers with different viscosities on both sides of the metal substrate. The upper layer has strong viscosity for fixation, and the lower layer has weak viscosity for operation. This structure has brought a major breakthrough in the automated operation process. It realizes the clear functional division of labor of "fixation first, then transcription" in production. Compared with the single-sided or uniform viscosity structure commonly used in the prior art, the present invention fundamentally solves the inherent defects of the automated process due to the inability to stabilize the operating reference, which easily leads to inaccurate positioning and process confusion.

[0044] 2. The present invention creatively combines ionic liquids and surface-modified multi-walled carbon nanotubes into a silicone rubber matrix. This unique formula design simultaneously gives the transfer paper excellent antistatic properties and an ultra-long cycle life. The ionic liquid constructs a charge discharge path, and the multi-walled carbon nanotubes form a microscopic reinforced skeleton. This is in sharp contrast to traditional technologies that rely solely on ordinary silicone or simply add antistatic agents. It solves the technical bottlenecks of single performance, easy electrostatic breakdown of precision components, poor mechanical properties, and inability to withstand high-frequency repeated use.

[0045] 3. The present invention uses plasma etching to construct microscopic serrations on the surface of the substrate, and uses a laser to punch exhaust holes arranged in a Fibonacci spiral. This series of precision processing methods achieves interfacial bonding and bubble-free bonding. The substrate microstructure firmly locks the silicone layer through a mechanical anchoring effect, and the unique exhaust holes provide an efficient escape path for air trapped during bonding. Compared with the prior art method of using direct coating on a smooth substrate or ordinary mechanical punching, the present invention completely avoids the fatal defects of weak interfacial bonding leading to the shedding of the adhesive layer and poor exhaust resulting in a large number of bubbles. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a schematic diagram of the process flow of the present invention. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the present specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0048] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0049] Please see the attached Figure 1 and attached Figure 2 : Example 1: Group allocation ratio: Methyl vinyl silicone rubber: 77.5 parts; hydrogenated castor oil: 5 parts; ionic liquid: 4 parts; multi-walled carbon nanotubes: 0.4 parts; platinum catalyst: 0.125 parts; fluorosilicone surfactant: 0.3 parts.

[0050] Preparation process: 1. Surface microstructure treatment of metal substrate: Metal substrate: copper foil, thickness 30 μm.

[0051] Plasma etching: sawtooth depth 1.25μm, arrangement density 650 / cm 2 .

[0052] The sawtooth aspect ratio is 1:3, and the microstructure is designed as a radial gradient arrangement.

[0053] 2. Preparation and mixing of functional silicone layer materials: Mixing of the strong silica gel layer: mixing temperature 35°C, stirring speed 1400 rpm, mixing time 50 minutes, vacuum degassing (vacuum degree -0.09 MPa).

[0054] Weak silica gel layer mixing: mixing temperature 30°C, stirring speed 1300 rpm, mixing time 45 minutes, vacuum degassing (vacuum degree -0.09 MPa).

[0055] 3. Coating and thermal curing treatment: Strong silicone coating thickness: 0.25mm, weak silicone coating thickness: 0.15mm.

[0056] Hot pressing curing: temperature 120℃, hot pressing time 30 minutes, pressure 0.4MPa.

[0057] After curing, apply release film.

[0058] 4. Die cutting and laser punching: Die cutting operation: tool pressure 30N, XY axis servo system control.

[0059] Laser drilling: positioning hole diameter is 0.8mm, hole spacing is 2.5mm, exhaust hole diameter is 0.2mm, hole density is 200 holes / cm 2 .

[0060] 5. Vacuum bonding and exhaust treatment: Vacuum degree: -0.09MPa, pulsation frequency: 5Hz, hot paste temperature: 60℃, processing time: 20 seconds.

[0061] 6. Final quality inspection and packaging: Dimension detection: laser interferometry.

[0062] Surface defects: AOI automatic detection.

[0063] Resistance test: Four-probe method, to test the electrical conductivity of metal substrates.

[0064] Peel force: 180° peel test.

[0065] Aperture and position accuracy: Verification of high-magnification microscopy system and recognition algorithm.

[0066] Example 2: Group allocation ratio: Methyl vinyl silicone rubber: 85 parts; hydrogenated castor oil: 3 parts; ionic liquid: 2 parts; multi-walled carbon nanotubes: 0.2 parts; platinum catalyst: 0.05 parts; fluorosilicone surfactant: 0.1 parts.

[0067] Preparation process: 1. Surface microstructure treatment of metal substrate: Metal substrate: tin foil, thickness 25 μm.

[0068] Plasma etching treatment: sawtooth depth 0.5μm, arrangement density 500 pieces / cm 2 , the sawtooth aspect ratio is 1:2.

[0069] 2. Preparation and mixing of functional silicone layer materials: Mixing of the strong silica gel layer: mixing temperature 30°C, stirring speed 1200 rpm, mixing time 45 minutes, vacuum degassing (vacuum degree -0.08 MPa).

[0070] Weak silica gel layer mixing: mixing temperature 25 ° C, stirring speed 1100 rpm, mixing time 40 minutes, vacuum degassing (vacuum degree -0.08 MPa).

[0071] 3. Coating and thermal curing treatment: Strong silicone coating thickness: 0.3mm, weak silicone coating thickness: 0.1mm.

[0072] Hot pressing curing: temperature 130℃, hot pressing time 40 minutes, pressure 0.5MPa.

[0073] After curing, apply release film.

[0074] 4. Die cutting and laser punching: Die cutting operation: tool pressure 35N, XY axis servo system control.

[0075] Laser drilling: positioning hole diameter is 0.5mm, hole spacing is 2.0mm, exhaust hole diameter is 0.3mm, hole density is 250 holes / cm 2 .

[0076] 5. Vacuum bonding and exhaust treatment: Vacuum degree: -0.1MPa, pulsation frequency: 6Hz, hot paste temperature: 70℃, processing time: 25 seconds.

[0077] 6. Final quality inspection and packaging: Dimension detection: laser interferometry.

[0078] Surface defects: AOI automatic detection.

[0079] Resistance test: Four-probe method, to test the electrical conductivity of metal substrates.

[0080] Peel force: 180° peel test.

[0081] Aperture and position accuracy: Verification of high-magnification microscopy system and recognition algorithm.

[0082] Example 3: Group allocation ratio: Methyl vinyl silicone rubber: 70 parts; hydrogenated castor oil: 7 parts; ionic liquid: 6 parts; multi-walled carbon nanotubes: 0.6 parts; platinum catalyst: 0.2 parts; fluorosilicone surfactant: 0.5 parts.

[0083] Preparation process: 1. Surface microstructure treatment of metal substrate: Metal substrate: tin foil, thickness 40 μm.

[0084] Plasma etching: sawtooth depth 2μm, arrangement density 800 / cm 2 , the sawtooth aspect ratio is 1:4.

[0085] 2. Preparation and mixing of functional silicone layer materials: Mixing of the strong silica gel layer: mixing temperature 40°C, stirring speed 1500 rpm, mixing time 60 minutes, vacuum degassing (vacuum degree -0.095 MPa).

[0086] Weak silica gel layer mixing: mixing temperature 35°C, stirring speed 1400 rpm, mixing time 50 minutes, vacuum degassing (vacuum degree -0.095 MPa).

[0087] 3. Coating and thermal curing treatment: Strong silicone coating thickness: 0.2mm, weak silicone coating thickness: 0.1mm.

[0088] Hot pressing curing: temperature 110℃, hot pressing time 20 minutes, pressure 0.3MPa.

[0089] After curing, apply release film.

[0090] 4. Die cutting and laser punching: Die cutting operation: tool pressure 20N, XY axis servo system control.

[0091] Laser drilling: positioning hole diameter is 1.0mm, hole spacing is 3.0mm, exhaust hole diameter is 0.1mm, hole density is 150 holes / cm 2 .

[0092] 5. Vacuum bonding and exhaust treatment: Vacuum degree: -0.08MPa, pulsation frequency: 4Hz, hot paste temperature: 50℃, processing time: 15 seconds.

[0093] 6. Final quality inspection and packaging: Dimension detection: laser interferometry.

[0094] Surface defects: AOI automatic detection.

[0095] Resistance test: Four-probe method, to test the electrical conductivity of metal substrates.

[0096] Peel force: 180° peel test.

[0097] Aperture and position accuracy: Verification of high-magnification microscopy system and recognition algorithm.

[0098] Comparative Example 1: Compared with Example 1, the difference is that the components of the functional silica gel layer do not contain ionic liquid, and the missing 4 parts by weight are supplemented by methyl vinyl silicone rubber, and the rest are the same.

[0099] Comparative Example 2: Compared with Example 1, the difference is that the functional silicone layer does not contain multi-walled carbon nanotubes, and the missing 0.4 parts by weight is supplemented by methyl vinyl silicone rubber, and the rest are the same.

[0100] Comparative Example 3: Compared with Example 1, the difference is that the functional silicone layers on the upper and lower sides of the metal substrate are prepared using the preparation and mixing process of the weak silicone layer, that is, the upper and lower layers are mixed under the conditions of a mixing temperature of 30°C, a stirring speed of 1300 rpm, and a mixing time of 45 minutes, and the rest are the same.

[0101] Comparative Example 4: Compared with Example 1, the difference is that step S1 "microstructure treatment of the metal substrate surface" is omitted in the preparation process, that is, a smooth copper foil whose surface has not been treated with plasma etching is used as the metal substrate, and the rest are the same.

[0102] Comparative Example 5: Compared with Example 1, the difference is that the laser punching step in step S4 is omitted in the preparation process, that is, no positioning holes and exhaust holes are set on the obtained transfer paper, and the rest are the same.

[0103] Comparative Example 6: Compared with Example 1, the difference is that a weak functional silicone layer is only set on one side of the metal substrate, and no silicone layer is set on the other side. The rest of the preparation process and parameters are the same as the corresponding parts of the weak silicone layer in Example 1.

[0104] Experiment 1: Purpose of the experiment: This experiment aims to quantitatively verify, through comparative testing, the decisive role played by the key chemical components in the functional silicone layer formula: ionic liquids and multi-walled carbon nanotubes, in the ultimate antistatic properties and cycle life of transfer paper.

[0105] Experimental groups: Sample of Example 1; sample of Comparative Example 1 (the formulation does not contain ionic liquid); sample of Comparative Example 2 (the formulation does not contain multi-walled carbon nanotubes).

[0106] Experimental steps: 1. Antistatic Performance Test: Samples from each group were placed under constant temperature and humidity conditions (25°C, 50% RH) for 2 hours. Using a high resistance meter, place the electrode on the surface of the weak functional silicone layer of the sample and apply a 100V test voltage. Hold for 60 seconds and read the surface resistance. Five random points were tested on each sample, and the average value was recorded.

[0107] 2. Cycle life test: Use a 180° peel force tester. Fix the strong silicone layer of each group of samples to the tester platform. Use a standard PET protective film as the adherend. Set the program to adhere the weak silicone layer of the sample to the PET protective film at a pressure of 5N for 2 seconds, then peel it 180° at a speed of 300mm / min, and record the initial peel force. Repeat this "bond-peel" cycle until the peel force drops below 50% of the initial value or the silicone layer shows visible damage. Record the total number of cycles at this point as the cycle life (experimental data is shown in Table 1).

[0108] Table 1: Comparative test data of key chemical components Sample number Surface resistance (Ω) Cycle life (times) Example 1 <![CDATA[2.8x10 8 ]]> 1835 Comparative Example 1 <![CDATA[4.9x10 12 ]]> 1790 Comparative Example 2 <![CDATA[3.5x10 8 ]]> 246 From Table 1, we can get: The experimental data clearly demonstrates that the sample of Example 1 exhibits significant superiority in both antistatic performance and cycle life, two key indicators. While the cycle life of Comparative Example 1 is comparable to that of Example 1, its surface resistivity is extremely high, indicating virtually no antistatic capability. While Comparative Example 2 resolves the static issue, its cycle life is extremely short, far from meeting the requirements for repeated use in actual production. This demonstrates the necessity of the synergistic effect of the components in the present invention's formulation.

[0109] The experimental results reveal the intrinsic mechanism of action of the present invention. The core difference between Example 1 and Comparative Example 1 lies in the presence or absence of ionic liquid. As a conductive medium, the ions of ionic liquid can migrate in the polymer network of silicone rubber, forming an effective charge discharge path, thereby controlling the surface resistance to 10 8The antistatic level of Ω effectively prevents the accumulation of static electricity from damaging the display components. Comparative Example 1 lacks this component and exhibits typical insulating properties, which cannot meet application requirements.

[0110] Comparing the results of Example 1 with those of Comparative Example 2 clearly demonstrates the structural reinforcement effect of multi-walled carbon nanotubes. The multi-walled carbon nanotubes that have undergone surface coating treatment can be evenly dispersed in the silica gel matrix to form a three-dimensional microscopic reinforcement skeleton. This skeleton greatly improves the toughness, shear resistance, and fatigue resistance of the silica gel layer, allowing the material to maintain its structural integrity and adhesion properties after thousands of high-intensity stretching and peeling. In contrast, in Comparative Example 2, due to the lack of support from this microscopic skeleton, its silica gel network is rapidly destroyed under repeated mechanical stress, resulting in a sharp decline in performance and the inability to achieve the design goal of long life.

[0111] Experiment 2: Comparative test of product structure and interface innovation performance Purpose of the experiment: This experiment aims to verify the necessity of the "double-sided differentiated adhesive structure" in the present invention for achieving orderly operation by simulating actual application scenarios, as well as the key role of "metal substrate surface microstructure treatment" in ensuring the long-term reliability of the product.

[0112] Experimental groups: Sample of Example 1; sample of Comparative Example 3 (the upper and lower silicone layers have the same viscosity); sample of Comparative Example 4 (using a smooth metal substrate without microstructuring treatment).

[0113] Experimental steps: 1. Functionality Verification Test: 20 samples each from Example 1 and Comparative Example 3 were collected. Simulating an automated process, the strong side of the sample (or a random side for Comparative Example 3) was first attached to a fixed base. The weak side (or the other side) was then used to adhere to and peel off the polarizer protective film from a standard glass plate. The number of successful completions of the "attachment-peeling" cycle was recorded, and the success rate was calculated.

[0114] 2. Substrate Adhesion Durability Test: Samples from Example 1 and Comparative Example 4 were subjected to a T-type peel cycle test using a fatigue testing machine. This test aims to forcibly separate the silicone layer from the metal substrate in the samples. The cyclic tension was set at 5 N and the frequency was 1 Hz. The number of cycles until delamination began to occur at the interface between the silicone layer and the metal substrate was recorded (experimental data are shown in Table 2).

[0115] Table 2: Comparative test data of product structure and interface innovation performance From Table 2, we can get: The experimental results clearly demonstrate the superiority of the structural innovation of the present invention. Comparative Example 3, due to the identical viscosity of the upper and lower layers, exhibited an extremely low success rate in the operational functionality test. Its failure mode was completely random, making it unsuitable for controlled automated production. Although Comparative Example 4 functioned normally during initial operation, it quickly failed in the substrate adhesion test, indicating that its structure was unreliable and could not withstand long-term use. Only Example 1 achieved both functionality and reliability, perfectly achieving the invention's purpose.

[0116] The fundamental reason for the failure of Comparative Example 3 is that its structure violates the core design concept of "functional zoning" in the present invention. By adopting a "strong top, weak bottom" adhesiveness differentiation, the present invention establishes a clear logical sequence for the automated operation process: the strong side is responsible for securely "locking" with the equipment, while the weak side is responsible for "operating" the product. However, the uniform adhesiveness of Comparative Example 3 results in disordered force distribution during operation, making it very easy for the peeling force to exceed the fixing force, leading to operational failure. This fully demonstrates that differentiated adhesiveness on both sides is a prerequisite for realizing the functions of the present invention.

[0117] The difference in durability between Example 1 and Comparative Example 4 profoundly reveals the importance of the microscopic physical structure of the interface. The smooth metal substrate used in Comparative Example 4 relies only on the weak van der Waals force between molecules for its bonding to the silicone layer. This bonding force is easily destroyed under repeated stress. In Example 1, a micron-scale serrated array is constructed on the surface of the metal substrate through a plasma etching process. During the coating and thermal curing process, liquid silicone will penetrate and fill these microscopic "grooves", and after curing, a powerful mechanical anchoring effect (or mechanical interlocking) is formed. This strong interlocking at the physical level makes the interface bonding force far exceed the molecular force, and can effectively resist the fatigue and shear force caused by long-term cyclic use, thereby fundamentally ensuring the long life and high reliability of the product.

[0118] Experiment 3: Purpose of the experiment: This experiment aims to verify the effectiveness of the "precision laser drilling structure" in solving the problem of lamination bubbles by simulating an automated production environment, as well as the necessity of the "double-sided structure" design for compatibility with automated equipment operations.

[0119] Experimental groups: Sample of Example 1; sample of Comparative Example 5 (not laser punched); sample of Comparative Example 6 (only one-sided weak silicone layer).

[0120] Experimental steps: 1. Lamination Degassing Performance Test: Samples from Example 1 and Comparative Example 5 were laminator-mounted onto a clean, transparent glass substrate using the same process parameters (vacuum level -0.09 MPa, lamination temperature 60°C, and lamination time 20 seconds). After lamination, the glass substrate was placed on a backlit optical inspection platform. A high-resolution camera was used to capture the lamination interface, and image analysis software was used to calculate the percentage of air bubbles in the total lamination area.

[0121] 2. Automated Process Applicability Test: An automated testing platform was constructed, including a vacuum suction cup robotic arm. The robotic arm was programmed to pick up the sample, move to the target station, and attach the sample to the protective film to be removed. This operation was repeated 20 times for each of the samples from Example 1 and Comparative Example 6. The number of times the robotic arm successfully completed the entire process of movement and attachment, with stable suction, was recorded, and the success rate was calculated (the experimental data is shown in Table 3).

[0122] Table 3: Comparative test data of automated application functions From Table 3 we can get: The above experimental results clearly demonstrate that the structural design of the present invention is indispensable for achieving automated applications. Although Comparative Example 5 can be operated, the large amount of bubbles remaining after lamination makes it lose its practical application value. Comparative Example 6 is fundamentally incompatible with automated equipment and fails at the first step of the process. Only the sample of Example 1 can perfectly fit without bubbles and seamlessly connect with automated equipment, fully demonstrating the integrity and advanced nature of the invention.

[0123] Comparing the results of Example 1 and Comparative Example 5 deeply reveals the core mechanism of the precision microporous structure in the bonding process. At the moment of bonding, air will inevitably be trapped between the two layers of film. For Comparative Example 5 without an exhaust channel, the air is "stifled" inside, forming fatal bubbles that affect the product yield. The microporous array constructed by laser punching in the present invention, especially the innovative exhaust holes arranged in a Fibonacci spiral, provides an efficient "escape channel" for these trapped air. Under the negative pressure of vacuum bonding, gas molecules will be rapidly extracted along these micropores, thereby achieving a nearly perfect bubble-free bonding, which is the basis for ensuring the success of high-precision transcription.

[0124] Comparing the applicability of the automated processes of Example 1 and Comparative Example 6 verifies the ingenuity of the double-sided structure of the present invention. Automated equipment (such as vacuum suction cups) need to be adsorbed on a clean, flat and non-sticky surface to work stably. Comparative Example 6 has only one side, with a metal substrate on the back and sticky silicone on the front. No matter which side is adsorbed, it cannot meet the requirements of automated operation. The double-sided structure of Example 1, covered with a release film, provides an ideal contact surface (the outer surface of the release film) for automated equipment. The robotic arm can stably adsorb, move and position, and remove the release film when necessary to proceed to the next step, which perfectly solves the problem of automated compatibility. This design is the key to upgrading the present invention from a simple material solution to a mature industrial product that can be seamlessly connected to a modern production line.

[0125] The examples of this specific embodiment are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, any equivalent changes made based on the structure, shape, and principle of this application should be included in the scope of protection of this application.

Claims

1. Transfer paper for display screen production, characterized in that: It includes a metal substrate, wherein functional silicone layers are provided on both the upper and lower sides of the metal substrate, a release film is provided on the outside of the functional silicone layer, and the functional silicone layer includes the following components in parts by weight: Methyl vinyl silicone rubber: 70-85 parts; Hydrogenated castor oil: 3-7 parts; Ionic liquid: 2-6 parts; Multi-walled carbon nanotubes: 0.2-0.6 parts; Platinum catalyst: 0.05-0.2 parts; Fluorosilicone surfactant: 0.1-0.5 parts.

2. The transfer paper for display screen production according to claim 1, characterized in that: The ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt; the multi-walled carbon nanotube has a diameter of 5-15 nm, a length of 1-10 μm, and is coated with a polyvinyl pyrrolidone coating; the iodine value of the hydrogenated castor oil is less than 4, and the hydroxyl value is 150-200 mgKOH / g.

3. The transfer paper for display screen production according to claim 1, characterized in that: The metal substrate is copper foil or tin foil with a thickness of 20-40 μm and a micron-level concave-convex structure on the surface. The sawtooth depth of the concave-convex structure is 0.5-2 μm and the arrangement density is 500-800 per cm. 2 ; The functional silicone layer includes a strong silicone layer and a weak silicone layer, wherein the viscosity range of the strong silicone layer is 1000-2500mPa·s, and the viscosity range of the weak silicone layer is 600-1200mPa·s.

4. The process for preparing the transfer paper for display screen production according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, surface microstructure treatment of metal substrate; S2. Preparation and mixing of functional silicone layer materials; S3, coating and heat curing treatment; S4, die-cutting and laser punching; S5, vacuum bonding and exhaust treatment; S6. Final quality inspection and packaging.

5. The process for preparing transfer paper for display screen production according to claim 4, characterized in that: The metal substrate surface microstructure treatment comprises the following steps: A copper foil or tin foil with a thickness of 20-40 μm is used as a metal substrate, and a plasma etching process is used to perform microstructural treatment on its surface, so that a uniformly distributed micro-serrated structure is formed on the metal surface. The micro-serrated structure has the following characteristics: The sawtooth depth is 0.5-2μm; The aspect ratio of the saw teeth is 1:2-1:4; The arrangement is radial gradient distribution.

6. The process for preparing transfer paper for display screen production according to claim 4, wherein: The preparation and mixing of the functional silica gel layer material comprises the following steps: Add the components of the functional silica gel layer in proportion to the mixing device for uniform mixing and vacuum degassing. The mixing conditions are as follows: Strong silica gel layer: mixing temperature is 30-40℃, stirring speed is 1200-1500rpm, and mixing time is 45-60 minutes; Weak silica gel layer: mixing temperature is 20-30°C, stirring speed is 1000-1200 rpm, and mixing time is 30-45 minutes; Vacuum degassing is then carried out, and the vacuum degree is controlled at -0.08 to -0.095 MPa.

7. The process for preparing transfer paper for display screen production according to claim 4, characterized in that: The coating and heat curing process comprises the following steps: The obtained mixed functional silicone layer material is coated according to the coating thickness of 0.2-0.3mm for the strong silicone material and 0.1-0.2mm for the weak silicone material; After coating, hot pressing curing is carried out at a temperature of 110-130°C, the hot pressing time is 20-40 minutes, and the pressure is 0.3-0.5MPa; After curing, a release film is applied to the surface of the functional silicone layer.

8. The process for preparing transfer paper for display screen production according to claim 4, wherein: The die cutting and laser punching process includes the following steps: Die cutting and punching operations are performed on the solidified structural materials. The die cutting is controlled by the XY axis servo system to position and cut the die cutter. The tool pressure is 20-40N. Microhole array drilling using a pulsed laser drilling system: The positioning holes have a diameter of 0.5-1.0 mm, are closely packed in a hexagonal pattern, and have a hole spacing of 1.5-3.0 mm; The vent holes have a diameter of 0.1-0.3 mm and are arranged in a Fibonacci spiral structure. The density increases by 10-20% along the peeling direction, and the hole density is 150-300 holes / cm 2 ; The laser wavelength is 1064nm, the pulse width is 8-12ns, and the energy density is 2.8-3.5J / cm 2 , the focused spot diameter is 10-30μm.

9. The process for preparing transfer paper for display screen production according to claim 4, wherein: The vacuum lamination and exhaust process includes the following steps: The die-cut and punched structural parts are subjected to exhaust lamination in a vacuum laminating device. The process is as follows: Vacuum degree is -0.08 to -0.1 MPa; The pulsation frequency is 3-7Hz, and the pressure difference amplitude is ±0.01MPa; The temperature of the thermal paste is controlled at 50-70°C and the processing time is 10-30 seconds; And remove the trapped air through the exhaust holes.

10. The process for preparing transfer paper for display screen production according to claim 4, characterized in that: The final quality inspection and packaging includes the following steps: The following items are fully inspected and sampled on the completed transfer paper: Dimension detection uses laser interferometry; Surface defects are identified by the AOI automatic inspection system; The electrical conductivity was tested by the four-probe resistance method; Adhesion performance was evaluated by 180° peel test for peel force; The position and aperture accuracy of the microwell array are verified by a high-magnification microscopic imaging system in conjunction with a recognition algorithm; After passing the inspection, the products will be carefully cut, packaged and cleanly packed.

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