Liquid crystal laminated glass with polarizer, preparation method and vehicle containing the same

Abstract

The present invention discloses a liquid crystal laminated glass with polarizers, a preparation method, and a vehicle containing the same. The present invention separates the upper and lower polarizers of a polarized liquid crystal element from a diaphragm substrate, and laminates them with the upper and lower layers of glass through a polymer intermediate layer to form upper and lower laminates. The liquid crystal element without upper and lower polarizers is integrated with the upper and lower laminates by arranging a liquid optically transparent adhesive and cross-linking and curing it to form a multi-layer liquid crystal laminated glass. The two polarizers and the diaphragm substrate of the liquid crystal element are separated, and even if the polarizer expands or warps after being heated or irradiated, it will not cause squeezing of the liquid crystal element, resulting in poor appearance. In addition, the upper and lower laminates are bonded using a liquid optically transparent adhesive to avoid the temperature and pressure required in the lamination process causing permanent poor appearance, liquid crystal loss, bubbles, and other defects to the liquid crystal element. In addition, the strong bond formed during the lamination of the upper and lower laminates can also effectively suppress the expansion and warping tendency of the polarizer.

Description

Technical Field

[0001] The present invention relates to the field of automobile glass, and in particular to a liquid crystal laminated glass with a polarizer, a preparation method and a vehicle comprising the same. Background Art

[0002] Currently, laminated windows with variable transmittance using liquid crystals mostly utilize guest-host liquid crystal elements (LCEs). These elements are formed by laminating a polymer interlayer or by applying a liquid optically clear adhesive and cross-linking and curing. Guest-host LCEs achieve transmittance adjustment by deflecting the liquid crystal molecules within the cell, which in turn pushes the dichroic dye molecules. Another type of LCE is the polarized LCE, which typically uses a flexible substrate such as polyethylene terephthalate (PET) or polycarbonate (PC). These LCEs feature two linear polarizers on either side of the cell, with polarization directions perpendicular to each other. The LCE is encapsulated by a membrane substrate and a sealed joint, and contains a liquid crystal mixture, an electrode layer, and an alignment layer. The LCE contains no dye molecules. Natural light becomes linearly polarized after passing through the first polarizer. The electric field causes the LC molecules to rotate, adjusting the polarization direction of the incident light. According to Malus's law, transmittance is proportional to the square of the cosine of the angle between the polarization direction of the incident light and the polarization direction of the second polarizer.

[0003] Currently, there are three common ways to implement laminated windows containing variable transmittance liquid crystal elements:

[0004] a. By arranging a liquid optically transparent adhesive and cross-linking and curing the liquid crystal element between two layers of glass (one of which is laminated glass), such as Chinese patent publication CN112351883A;

[0005] b. First, a liquid crystal element, a polymer interlayer, and glass are bonded together by lamination to form a laminated assembly, and then the laminated assembly is bonded to another layer of glass by disposing a liquid optically transparent adhesive and cross-linking and curing the adhesive to form a laminated vehicle window; for example, Chinese patent publication CN114585507A;

[0006] c. Connecting the liquid crystal element and the single-layer polarizer to the vehicle window glass body through an adhesive material to form a composite structure; for example, Chinese patent publication CN110869837A.

[0007] A common feature of both implementations (a) and (b) is that one or both sides of the liquid crystal element are in contact with the liquid optically clear adhesive. Because the liquid optically clear adhesive is in a liquid state before curing, with a low viscosity (typically 100-6000 mPa.s, with a common viscosity of 200-2000 mPa.s), and a low hardness after curing (typically Shore 00 40-60), the force applied to the liquid crystal element before and after curing is relatively small, making it less likely to cause permanent cosmetic defects during the curing process.

[0008] Polarized flexible liquid crystal elements (LCDs) have polarizers attached to their film substrates. These polarizers are made of different materials and have different thermal expansion coefficients. Furthermore, residual stress forms during the polarizer manufacturing and packaging processes. These factors can cause the LCDs to swell or warp when exposed to heat or radiation. If the polarization directions of the upper and lower polarizers are perpendicular, the warping directions on both sides of the LCD may be perpendicular to each other. Liquid optically transparent adhesives are relatively soft after curing, making it difficult to limit the expansion and warping of the LCDs themselves. This expansion and warping can cause variations in the thickness of the LCDs in nearby locations, further leading to localized transmittance or color unevenness (mura) in the liquid crystals near these locations. Because warping in LCDs is difficult to completely resolve after exposure to high temperatures or intense radiation, some of the visual defects can remain, creating permanent cosmetic issues. Severe deformation can even lead to localized loss of liquid crystal or fractures in the film substrate, permanently losing the transmittance adjustment function.

[0009] Method a requires at least three layers of glass, significantly increasing the thickness and weight of the product, which is inconsistent with the current environmentally friendly approach of lightweighting and reducing energy consumption. In method b, the liquid crystal element and glass are bonded together through lamination. Traditional automotive glass lamination processes generally require temperatures exceeding 130°C and pressures exceeding 1 MPa. Because the liquid crystal and dye molecules in existing liquid crystal elements are highly sensitive to cell thickness and processing temperature, process temperatures exceeding 100°C and pressures exceeding 0.1 MPa often lead to localized, irreversible cosmetic defects during the lamination process. To address this issue, specialized materials such as low-temperature EVA and TPU are often required during the lamination process for curved glass. Even with low-temperature materials, temperatures exceeding 100°C and pressures exceeding 0.1 MPa are often required to achieve a uniform, transparent, bubble-free laminated window. This often requires the development and verification of specialized new materials, complex process adjustments, and extended lamination times. Low-temperature, low-pressure lamination processes can also lead to weakened bonding strength and incomplete degassing, posing potential risks to product reliability. The inventors have experimentally proved that if lamination is performed at a low temperature below 110°C and a pressure of 1 bar, a large number of bubbles will easily appear between the commonly used polymer adhesive layer material polyvinyl butyral (PVB) and the liquid crystal element after high-temperature testing. In method c, the liquid crystal element is connected to the inner or outer layer of the window glass through an adhesive layer, and a single polarizer is arranged between the liquid crystal element and the inner or outer layer of the window glass. In order to achieve the shielding effect, the liquid crystal element in method c must have polarization properties in order to achieve the shielding effect after being combined with the polarizer. In actual applications, the polarization degree of liquid crystal elements with polarization properties is limited, that is, natural light is not completely linearly polarized light after being filtered by the liquid crystal element, which results in a high dark state transmittance of the liquid crystal element with a single polarizer or a narrower overall transmittance adjustment range. Summary of the Invention

[0010] The present invention aims to provide a liquid crystal laminated glass with polarizers, a preparation method, and a vehicle incorporating the same. This method separates the upper and lower polarizers of a polarized liquid crystal element from a film substrate, bonds them to the upper and lower glass layers, and then integrates them with the liquid crystal element encapsulated by the film substrate to form a laminated vehicle window glass. This method avoids localized transmittance or color unevenness (mura) in the liquid crystal element caused by thermal expansion coefficients and inherent stress between the polarizers and the film substrate, as well as permanent defects such as poor appearance, missing liquid crystal, and bubbles caused by the temperature and pressure required during the lamination process.

[0011] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0012] In one aspect, the present invention provides a method for preparing liquid crystal laminated glass with a polarizer, the method comprising the following steps:

[0013] combining the upper polarizer with the upper glass to form an upper laminate;

[0014] combining the lower polarizer with the lower glass to form a lower laminate;

[0015] Integration: The liquid crystal element encapsulated by the film substrate without the polarizer is sandwiched between the upper laminate and the lower laminate by arranging a liquid optically transparent adhesive and cross-linking and curing it to form the liquid crystal laminated glass.

[0016] In the present invention's manufacturing method, the two polarizers and the liquid crystal cell's film substrate are separated and filled with a liquid, optically transparent adhesive. This prevents the polarizers from expanding or warping due to heat or radiation exposure, without squeezing the liquid crystal cell and causing a poor appearance. Furthermore, the liquid crystal cell is bonded using a liquid, optically transparent adhesive, avoiding the potential for permanent cosmetic or other defects caused by the high temperatures and pressures required during the lamination process.

[0017] According to the preparation method of the present invention, preferably, the liquid optically transparent adhesive can be selected from one or more of the following materials: acrylic, polyvinyl acetate (PVA), polyurethane (PU), silicone resin, epoxy resin, and the like.

[0018] According to the preparation method of the present invention, preferably, the forming process of the upper laminate comprises:

[0019] The upper glass, first polymer interlayer, upper polarizer, first barrier layer, and first back glass are stacked in sequence to form a laminated structure. After securing their relative positions, the laminate is placed in a vacuum bag and laminated using a low-temperature, high-pressure process. After lamination, the vacuum bag is removed, and the first barrier layer and first back glass are removed, leaving the upper laminate formed by the upper glass, first polymer interlayer, and upper polarizer. During this process, the first polymer interlayer is indented 1-10 mm from the edge of the glass to facilitate the subsequent placement of edge seals.

[0020] According to the preparation method of the present invention, preferably, the formation process of the lower laminate comprises:

[0021] The lower glass, second polymer interlayer, lower polarizer, second barrier layer, and second back glass are stacked in sequence to form a laminated structure. After securing their relative positions, the laminate is placed in a vacuum bag and laminated using a low-temperature, high-pressure process. After lamination, the vacuum bag is removed, and the second barrier layer and second back glass are removed, leaving behind a lower laminate consisting of the lower glass, second polymer interlayer, and lower polarizer. During this process, the second polymer interlayer is indented 1-10 mm from the glass edges to facilitate the subsequent placement of edge seals.

[0022] During the formation of the upper and lower laminates, the polarizer is bonded to the glass using a polymer interlayer and a lamination process. High pressure can be used, avoiding complex lamination process adjustments and issues such as weakened bonding material and incomplete gas removal that can occur with low-pressure processes. This provides better compatibility with existing production lines and operators. Preferably, the low-temperature, high-pressure lamination process uses a pressure of 10 bar or higher, for example, 10 to 13 bar, and a temperature between 110°C and 80°C.

[0023] Furthermore, the strong bond formed during lamination of the upper and lower laminates effectively inhibits the polarizer's tendency to expand and warp. The polymer interlayer effectively blocks UV rays from sunlight, protecting the liquid crystal element within.

[0024] The use of back glass during the production of upper and lower laminates ensures a smooth surface for the polymer interlayer. The use of a barrier layer ensures smooth removal of the back glass after lamination. A smooth barrier layer ensures a smooth surface for the polymer interlayer during lamination. Furthermore, because organic solvents can damage some polymer interlayers, the surface of the polymer interlayer should be kept clean or cleaned as little as possible. Therefore, the barrier layer can be temporarily retained in subsequent processes to protect the polymer interlayer from contamination.

[0025] According to the preparation method of the present invention, preferably, the material of the barrier layer is selected from PET, nylon, silicone or Teflon; the barrier layer can be a single layer or multiple layers, and the size of the barrier layer should be at least equal to or larger than the outer size of the glass.

[0026] According to the preparation method of the present invention, the materials for the first and second polymer interlayers can preferably be selected from the following polymers: polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU), polyethylene terephthalate (PET), polyethylene, polycarbonate, polymethyl methacrylate, polyacrylate, polyvinyl chloride, polyacetate resin, acrylate, fluorinated ethylene propylene, polyvinyl fluoride, ethylene tetrafluoroethylene, and cyclic olefin copolymer (COC). By selecting the materials and components of the polymer interlayers, the glass can maintain mechanical strength and also possess various functions such as sound insulation, infrared and ultraviolet radiation shielding, and coloring.

[0027] According to the preparation method of the present invention, preferably, the specific process of the integration includes: embedding the liquid crystal element inside the liquid optically transparent adhesive and sandwiching it between the upper laminate and the lower laminate; after the liquid optically transparent adhesive is cured, the upper laminate and the lower laminate are bonded together by the liquid optically transparent adhesive to form the liquid crystal laminated glass.

[0028] According to the preparation method of the present invention, preferably, before the integration, peripheral seals are provided at the edges of the upper laminate and the lower laminate so that the upper laminate and the lower laminate maintain a certain distance when bonded by the liquid optically transparent adhesive; an opening is reserved on the peripheral seal for pouring the liquid optically transparent adhesive during integration.

[0029] Alternatively, a liquid optically transparent adhesive is first arranged in the upper laminate or the lower laminate and the liquid crystal element is embedded therein, and then the upper laminate and the lower laminate are combined. After the liquid optically transparent adhesive is cured, peripheral seals are provided on the four opposite edges of the upper laminate and the lower laminate.

[0030] In a preferred embodiment, prior to integration, a peripheral seal is placed between the edge regions of the liquid crystal element and one of the upper and lower laminates. This peripheral seal can be a double-sided adhesive strip of relatively fixed thickness (such as the 3MVHB series), a silicone or polyurethane structural adhesive with a fixed thickness and width, or a combination of fixed-thickness double-sided adhesive strips and structural adhesive. The peripheral seal has a width of 1 to 10 mm and a height of 0.1 to 2 mm. Two or more openings are reserved in the peripheral seal for pouring the liquid optically clear adhesive.

[0031] As another preferred embodiment, a liquid optically transparent adhesive may be first provided on the surface of one of the upper and lower laminates facing the liquid crystal cell, or on the surface of the liquid crystal cell facing the laminates, and then one of the upper and lower laminates may be bonded to the liquid crystal cell. After the liquid optically transparent adhesive is cured, the bonding of one of the upper and lower laminates to the liquid crystal cell is completed.

[0032] After integrating the liquid crystal cell with one of the upper and lower laminates, a peripheral seal is placed in the indented area of the polymer interlayer at the edges of the upper and lower laminates. This peripheral seal can be a double-sided adhesive strip of relatively fixed thickness (such as the 3M VHB series), a silicone or polyurethane structural adhesive with a fixed thickness and width, or a combination of fixed-thickness double-sided adhesive strips and structural adhesive. The peripheral seal should be 1 to 10 mm wide and 0.2 to 2 mm taller than the combined thickness of the liquid crystal cell, upper and lower polarizers, and the first and second polymer interlayers.

[0033] The peripheral seal is primarily used to connect the upper and lower laminates, and together with them, forms a sealed structure with a certain height, preventing foreign particles, moisture, liquids, etc. from entering the sealed structure. The peripheral seal can be made of opaque black, or transparent but UV-blocking material to prevent UV rays from entering the product through the glass edges and causing degradation of the liquid crystal elements. The peripheral seal has a reserved opening for the injection of the liquid optically clear adhesive during assembly. After the liquid optically clear adhesive is injected, the injection port can be sealed with a secondary adhesive injection.

[0034] In another preferred embodiment, after the liquid crystal cell is first integrated with one of the upper and lower laminates, a barrier material such as polytetrafluoroethylene or silicone is optionally placed in the indented area of the polymer interlayer of the upper and lower laminates. The height of the barrier material is 0.2 to 2 mm greater than the combined thickness of the liquid crystal cell, upper and lower polarizers, and the first and second polymer interlayers. A liquid optically clear adhesive is then applied to the surface of the other layer of the upper and lower laminates or the liquid crystal cell, and the upper and lower laminates are bonded. After the liquid optically clear adhesive cures, the barrier material is removed. A peripheral seal is then formed by injecting a silicone or polyurethane structural adhesive into the gaps around the opposing edges of the upper and lower laminates.

[0035] Another aspect of the present invention provides a liquid crystal laminated vehicle window glass with a polarizer, which is obtained by the above preparation method.

[0036] Specifically, the liquid crystal laminated window glass comprises an upper layer of glass, a first polymer interlayer, an upper polarizer, a liquid optically transparent adhesive, a lower polarizer, a second polymer interlayer and a lower layer of glass stacked in sequence;

[0037] A liquid crystal element is embedded in the liquid optically transparent adhesive, and the upper polarizer, the liquid crystal element and the lower polarizer correspond to each other in a stacking direction.

[0038] The liquid crystal element can be positioned directly between the upper and lower polarizers, or closer to one side. This means the adhesive thickness between the liquid crystal element and the upper and lower layers can be different. The adhesive is typically applied in two steps, and different compositions of liquid optically clear adhesive can be used.

[0039] The liquid crystal laminated glass further comprises a peripheral sealant, which is arranged on the four edges of the upper and lower window glasses, and the two ends of the peripheral sealant are respectively connected to the upper and lower glass layers.

[0040] The beneficial effects of the present invention include:

[0041] 1) Existing liquid crystal laminated glass technologies (such as the three implementation methods in the background technology) mostly use guest-host liquid crystal elements. This type of liquid crystal element generally has difficulty reducing the transmittance below 1% (unless the bright state transmittance is reduced to below 15%), and there is a problem of high dark state transmittance. In addition, the guest-host liquid crystal elements currently on the market have problems such as greatly increased response time at low temperatures (>10s), which limits the application of this type of element in the passenger car field. Polarized liquid crystal elements can easily reduce the transmittance to below 1% while ensuring a bright state transmittance of more than 30% due to the orthogonal arrangement of the upper and lower polarizers. The transmittance adjustment range is more ideal.

[0042] 2) The two polarizers and the liquid crystal cell film substrate are separated and filled with a liquid optically transparent adhesive. Even if the polarizer expands and warps after being heated or irradiated, it will not squeeze the liquid crystal cell and cause poor appearance or other defects.

[0043] 3) The polarizer is bonded to the glass using a polymer interlayer and a lamination process, which allows for high pressure (above 10 bar). This avoids the complex lamination process debugging and the problems of weakened bonding materials and incomplete gas removal that may be caused by low-pressure processes, making it more compatible with existing production lines and operators. In addition, the strong bond formed during the lamination of the upper and lower laminates can effectively suppress the expansion and warping tendencies of the polarizer.

[0044] 4) The liquid crystal element is bonded using a liquid optically transparent adhesive, which avoids the temperature and pressure required in the lamination process causing permanent poor appearance or other defects in the liquid crystal element;

[0045] 5) Using back glass when making upper and lower laminates ensures a smooth surface for the polymer interlayer. Using a barrier layer ensures that the back glass can be removed smoothly after lamination, and a smooth barrier layer ensures a smooth surface for the polymer interlayer during the lamination process. In addition, the barrier layer can be temporarily retained in subsequent processes to continue protecting the polymer interlayer from contamination.

[0046] 6) The polymer intermediate layer in the upper laminate can effectively block ultraviolet rays in sunlight and protect the internal liquid crystal elements.

[0047] 7) The peripheral seal is directly connected to the upper and lower layers of glass, which increases the bonding strength between the upper and lower layers of glass and, to a certain extent, avoids the situation where the product is damaged due to dislocation caused by external shear force. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 Schematic diagram of the formation process of the upper and lower laminates in the present invention.

[0049] Figure 2 This is a schematic structural diagram of the liquid crystal laminated glass with polarizer of the present invention.

[0050] Figure 3 FIG. 1 is a schematic structural diagram of a liquid crystal laminated glass with a polarizer in another preferred embodiment of the present invention.

[0051] Description of reference numerals:

[0052] 1-glass, 11-upper glass, 12-lower glass;

[0053] 2-polymer intermediate layer, 21-first polymer intermediate layer, 22-second polymer intermediate layer;

[0054] 3-polarizer, 31-upper polarizer, 32-lower polarizer;

[0055] 4-barrier layer, 41-first barrier layer, 42-second barrier layer;

[0056] 5-Back glass;

[0057] 6-Liquid optically clear adhesive;

[0058] 7-Liquid crystal element;

[0059] 8- Peripheral seal. DETAILED DESCRIPTION

[0060] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. Those skilled in the art should understand that the following specific description is illustrative rather than restrictive and should not be used to limit the scope of protection of the present invention.

[0061] The main technical solution provided by the present invention is achieved through the following process: separating the upper and lower polarizers of the polarized liquid crystal element from the film substrate, laminating the upper polarizer and the upper glass through a first polymer interlayer to form an upper laminate, and laminating the lower polarizer and the lower glass through a second polymer interlayer to form a lower laminate; and integrating the liquid crystal element without upper and lower polarizers with the upper and lower laminates by arranging and curing a liquid optically transparent adhesive to form a multi-layer liquid crystal laminated glass.

[0062] In this invention, the two polarizer layers and the liquid crystal cell film substrate are separated and filled with a liquid, optically clear adhesive. Even if the polarizer warps due to heat or radiation, it will not squeeze the liquid crystal cell and cause poor appearance. Furthermore, the liquid crystal cell is bonded using a liquid, optically clear adhesive, avoiding the temperature and pressure required during the lamination process that can cause permanent mura or other defects. Furthermore, the strong bond formed during the lamination of the upper and lower laminates effectively suppresses the polarizer's tendency to warp.

[0063] The preparation method of the present invention mainly comprises the following steps:

[0064] combining the upper polarizer with the upper glass to form an upper laminate;

[0065] combining the lower polarizer with the lower glass to form a lower laminate;

[0066] Integration: The liquid crystal element encapsulated by the film substrate without the polarizer is sandwiched between the upper laminate and the lower laminate by arranging and curing the liquid optically transparent adhesive (liquid optically transparent adhesive) to form the liquid crystal laminated glass.

[0067] The liquid optically transparent adhesive (liquid optically transparent adhesive) is selected from one or more of the following materials: acrylic, polyvinyl acetate (PVA), polyurethane (PU), silicone resin, epoxy resin, and the like.

[0068] like Figure 1 As shown, the specific upper and lower laminates can be formed by the following process:

[0069] Glass 1, polymer interlayer 2, polarizer 3, barrier layer 4, and back glass 5 are stacked in sequence to form a laminated structure. After securing their relative positions, the glass is placed in a vacuum bag and laminated using a low-temperature, high-pressure (above 10 bar) process. After lamination, the vacuum bag is removed, and the barrier layer 4 and back glass 5 are removed, leaving behind the laminated structure consisting of glass 1, polymer interlayer 2, and polarizer 3, known as the upper or lower laminate. During this process, the polymer interlayer is indented 1 to 10 mm from the glass edges to facilitate the subsequent placement of edge seals.

[0070] During the formation of the upper and lower laminates, the polarizer 3 is bonded to the glass 1 using the polymer interlayer 2 and a lamination process. High pressure (above 10 bar) can be used, avoiding complex lamination process adjustments and the potential problems of weakened bonding materials and incomplete gas removal that may arise from low-pressure processes. This provides a better fit with existing production lines and operators. Preferably, the low-temperature, high-pressure process used for lamination has a pressure of above 10 bar, for example, 10 to 13 bar, and a temperature between 110°C and 80°C.

[0071] The material of the barrier layer 4 is preferably selected from PET, nylon or Teflon; the barrier layer 4 can be a single layer or multiple layers, and the size of the barrier layer 4 should be at least equal to or larger than the outer dimensions of the glass 1. Figure 1 The middle barrier layer includes a first barrier layer 41 and a second barrier layer 42 , wherein the first barrier layer 41 can also form a semi-enclosed structure to enclose and fix the laminated structure of the glass 1 , the polymer intermediate layer 2 and the polarizer 3 .

[0072] The polymer interlayer can be made from the following polymers: polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU), polyethylene terephthalate (PET), polyethylene, polycarbonate, polymethyl methacrylate, polyacrylate, polyvinyl chloride, polyacetate resin, acrylate, fluorinated ethylene propylene, polyvinyl fluoride, ethylene tetrafluoroethylene, and cyclic olefin copolymer (COC). By selecting the material and composition of the polymer interlayer, the glass can maintain mechanical strength while also providing various functions such as sound insulation, infrared and ultraviolet radiation shielding, and coloring.

[0073] The use of back glass 5 during the production of the upper and lower laminates ensures a smooth surface for the polymer interlayer 2. The use of a barrier layer 4 ensures smooth removal of the back glass 5 after lamination. Furthermore, the smooth surface of the barrier layer 4 ensures a smooth surface for the polymer interlayer 2 during the lamination process. Furthermore, because organic solvents may damage portions of the polymer interlayer 2, the surface of the polymer interlayer 2 should be kept clean or cleaned as little as possible. Therefore, the barrier layer 4 can be temporarily retained in subsequent processes to continue protecting the polymer interlayer 2 from contamination.

[0074] The specific upper laminate can be formed by the following process:

[0075] The upper glass, first polymer interlayer, upper polarizer, first barrier layer, and first back glass are stacked in sequence to form a laminated structure. After securing their relative positions, the laminate is placed in a vacuum bag and laminated using a low-temperature, high-pressure (above 10 bar) process. After lamination, the vacuum bag is removed, and the first barrier layer and first back glass are removed, leaving behind a lower laminate consisting of the upper glass, first polymer interlayer, and upper polarizer. During this process, the first polymer interlayer is indented 1-10 mm from the glass edges to facilitate the subsequent placement of edge seals.

[0076] The specific lower laminate can be formed by the following process:

[0077] The lower glass, second polymer interlayer, lower polarizer, second barrier layer, and second back glass are stacked in sequence to form a laminated structure. After securing their relative positions, the laminate is placed in a vacuum bag and laminated using a low-temperature, high-pressure (above 10 bar) process. After lamination, the vacuum bag is removed, and the second barrier layer and second back glass are removed, leaving behind the lower laminate formed by the lower glass, second polymer interlayer, and lower polarizer. During this process, the second polymer interlayer is indented 1-10 mm from the glass edges to facilitate the subsequent placement of edge seals.

[0078] The specific process of integrating the upper and lower laminates includes: embedding the liquid crystal element inside the liquid optically clear adhesive and sandwiching it between the upper and lower laminates; after the liquid optically clear adhesive is cured, the upper and lower laminates are bonded together by the liquid optically clear adhesive to form a multi-layer liquid crystal laminated glass.

[0079] like Figure 2 As shown, the liquid crystal laminated glass with polarizer obtained after integration includes an upper glass 11, a first polymer interlayer 21, an upper polarizer 31, a liquid optically transparent adhesive 6, a lower polarizer 32, a second polymer interlayer 22 and a lower glass 12 stacked in sequence;

[0080] The liquid crystal element 7 is embedded in the liquid optically transparent adhesive 6 , and the upper polarizer 31 , the liquid crystal element 7 and the lower polarizer 32 correspond to each other in the stacking direction.

[0081] like Figure 3 As shown, the liquid crystal laminated glass with polarizers also includes a peripheral seal 8, which is disposed around the edges of the liquid optically transparent adhesive 6. The ends of the peripheral seal 8 are connected to the upper glass 11 and the lower glass 12, respectively; the inner edge is connected to the first polymer interlayer 21, the second polymer interlayer 22, and the optically transparent adhesive 6. The peripheral seal 8 is directly connected to the upper and lower glass layers, enhancing the bonding strength between them and, to a certain extent, preventing misalignment due to external shear forces, which could lead to product damage.

[0082] In a preferred embodiment, before the integration, a peripheral seal 8 is provided at the edges of the upper laminate and the lower laminate so that the upper laminate and the lower laminate maintain a certain distance when bonded by the liquid optically transparent adhesive; an opening is reserved on the peripheral seal 8 for pouring the liquid optically transparent adhesive during the integration and curing to form the liquid optically transparent adhesive 6.

[0083] In another preferred embodiment, a liquid optically transparent adhesive is first arranged in the upper laminate or the lower laminate and the liquid crystal element 7 is embedded, and then the upper laminate and the lower laminate are combined. After the liquid optically transparent adhesive is cured to form a liquid optically transparent adhesive 6, a peripheral seal 8 is provided on the four relative edges of the upper laminate and the lower laminate.

[0084] The peripheral seal 8 primarily connects the upper and lower laminates and, together with them, forms a sealed structure with a defined internal volume to prevent foreign particles, moisture, and liquids from entering the sealed structure. The peripheral seal 8 can be opaque black, or transparent but UV-blocking to prevent UV rays from entering the product through the glass edges and causing degradation of the liquid crystal elements. An opening is reserved in the peripheral seal 8 for injecting the liquid optically transparent adhesive during assembly. After injection, the injection port can be sealed with a secondary adhesive injection.

[0085] The specific setting process of the peripheral seal 8 is as follows:

[0086] 1) Prior to integration, a peripheral seal 8 is placed between the peripheral edge of the liquid crystal element 7 and one of the upper and lower laminates. This peripheral seal 8 can be a double-sided adhesive strip of relatively fixed thickness (such as the 3M VHB series), a silicone or polyurethane structural adhesive with a fixed thickness and width, or both. The peripheral seal has a width of 1-10 mm and a height of 0.1-2 mm. Two or more openings are reserved in the peripheral seal for pouring the liquid optically transparent adhesive.

[0087] 2) A liquid optically transparent adhesive 6 may be first provided on the surface of one layer of the upper and lower laminates facing the liquid crystal element 7 or on the surface of the liquid crystal element 7 facing the laminates, and then one layer of the upper and lower laminates may be bonded to the liquid crystal element 7. After the liquid optically transparent adhesive 6 is cured, the bonding between the one layer of the upper and lower laminates and the liquid crystal element 7 is completed.

[0088] After integrating the liquid crystal element 7 with one of the upper and lower laminates, a peripheral seal 8 is placed in the indented area of the polymer interlayer 2 at the edges of the upper and lower laminates. The peripheral seal 8 can be a double-sided adhesive strip of relatively fixed thickness (such as the 3M VHB series), or a silicone or polyurethane structural adhesive formed into an adhesive strip of a certain thickness and width. Furthermore, a combination of fixed-thickness double-sided adhesive strips and structural adhesive can be used. The peripheral seal 8 is 1 to 10 mm wide and its height is greater than or equal to 0.2 to 2 mm greater than the sum of the thicknesses of the liquid crystal element 7, upper and lower polarizers 31 and 32, and the first and second polymer interlayers 21 and 22.

[0089] 3) After integrating the liquid crystal element 7 with one of the upper and lower laminates, a barrier material such as polytetrafluoroethylene (PTFE) or silicone is optionally placed in the indented area of the polymer interlayer 2 of the upper and lower laminates. The height of the barrier material should be 0.2 to 2 mm greater than the combined thickness of the liquid crystal element, upper and lower polarizers, and the first and second polymer interlayers. Liquid optically transparent adhesive 6 is then applied to the other layer of the upper and lower laminates, or to the surface of the liquid crystal element 7. The upper and lower laminates are then bonded together, and the barrier material is removed after the liquid optically transparent adhesive 6 cures. A peripheral seal 8 is then installed by injecting a silicone or polyurethane structural adhesive into the gap around the opposing edges of the upper and lower laminates.

[0090] The present invention Figure 2 and Figure 3 In the liquid crystal laminated glass, 1) the two polarizers and the film substrate of the liquid crystal element are separated and filled with a liquid optically transparent adhesive. Even if the polarizer warps after being heated or irradiated, it will not squeeze the liquid crystal element and form mura. 2) The polarizer is bonded to the glass using a polymer interlayer and a lamination process. High pressure (above 10 bar) can be used, avoiding the complex lamination process debugging and the problems of weakened bonding material and incomplete gas removal caused by low-pressure processes. It is more compatible with the existing production line and operators. In addition, the strong bond formed during the lamination of the upper and lower laminates can effectively suppress the polarizer's warping tendency. 3) The liquid crystal element is bonded using a liquid optically clear adhesive, preventing the temperature and pressure required during the lamination process from causing permanent mura or other defects in the liquid crystal element. 4) The use of back glass in the production of the upper and lower laminates ensures a smooth surface for the polymer interlayer. The use of a barrier layer ensures that the back glass can be removed smoothly after lamination, and the smooth barrier layer ensures a smooth surface for the polymer interlayer during the lamination process. In addition, the barrier layer can be temporarily retained in subsequent processes to continue protecting the polymer interlayer from contamination. 5) The polymer interlayer in the upper laminate effectively blocks ultraviolet rays in sunlight, protecting the liquid crystal element inside.

[0091] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for preparing liquid crystal laminated glass with a polarizer, characterized in that: The preparation method comprises the following steps: combining the upper polarizer with the upper glass to form an upper laminate; combining the lower polarizer with the lower glass to form a lower laminate; Integration: sandwiching a liquid crystal element encapsulated by a film substrate without a polarizer between the upper laminate and the lower laminate by arranging and curing a liquid optically transparent adhesive to form the liquid crystal laminated glass; The formation process of the upper laminate includes: stacking the upper glass, the first polymer interlayer, the upper polarizer, the first barrier layer, and the first back glass in sequence to form a laminated structure; fixing the relative positions of the upper glass, placing the upper glass in a vacuum bag, and laminating the upper glass using a low-temperature, high-pressure process; removing the vacuum bag after lamination, and removing the first barrier layer and the first back glass to leave an upper laminate formed by the upper glass, the first polymer interlayer, and the upper polarizer; The formation process of the lower laminate includes: The lower glass, the second polymer interlayer, the lower polarizer, the second barrier layer, and the second back glass are stacked in sequence to form a laminated structure; after fixing their relative positions, they are placed in a vacuum bag and laminated using a low-temperature and high-pressure process; after lamination, the vacuum bag is removed and the second barrier layer and the second back glass are removed, leaving a lower laminate formed by the lower glass, the second polymer interlayer, and the lower polarizer.

2. The preparation method according to claim 1, characterized in that The lamination adopts a low-temperature and high-pressure process with a pressure of more than 10 bar and a temperature between 110° C. and 80° C.

3. The preparation method according to claim 1, characterized in that The specific process of the integration includes: The liquid crystal element is embedded in a liquid optically transparent adhesive and sandwiched between the upper laminate and the lower laminate; after the liquid optically transparent adhesive is cured, the upper laminate and the lower laminate are bonded together by the liquid optically transparent adhesive to form the liquid crystal laminated glass.

4. The preparation method according to claim 3, characterized in that Before the integration, peripheral seals are provided at the edges of the upper and lower laminates to maintain a certain distance between the upper and lower laminates when they are bonded by liquid optically transparent adhesive; an opening is reserved on the peripheral seal for pouring the liquid optically transparent adhesive during integration.

5. The preparation method according to claim 3, characterized in that Liquid optically transparent adhesive is first arranged in the upper laminate or the lower laminate and the liquid crystal element is embedded, and then the upper laminate and the lower laminate are combined. After the liquid optically transparent adhesive is cured, peripheral seals are provided on the four opposite edges of the upper laminate and the lower laminate.

6. A liquid crystal laminated glass with a polarizer, characterized in that: The liquid crystal laminated glass is obtained by the preparation method according to any one of claims 1 to 5.

7. The liquid crystal laminated glass with polarizer according to claim 6, characterized in that: The liquid crystal laminated glass comprises an upper layer of glass, a first polymer interlayer, an upper polarizer, a liquid optically transparent adhesive, a lower polarizer, a second polymer interlayer and a lower layer of glass which are stacked in sequence; A liquid crystal element is embedded in the liquid optically transparent adhesive, and the upper polarizer, the liquid crystal element and the lower polarizer correspond to each other in a stacking direction.

8. The liquid crystal laminated glass with polarizer according to claim 7, characterized in that: The liquid crystal laminated glass further comprises a peripheral sealant, which is arranged on the four edges of the liquid optically transparent adhesive, and two ends of the peripheral sealant are respectively connected to the upper glass and the lower glass.

9. A vehicle comprising the liquid crystal laminated glass with polarizer according to any one of claims 6 to 8.

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