Laminated bulletproof glass and manufacturing process

Abstract

Laminated bulletproof glass holds significant importance in research and development efforts aimed at enhancing material performance and the manufacturing process of laminated bulletproof glass itself. The objective is to create laminated bulletproof glass sheets that incorporate layers of float glass, high-strength synthetic glass, or high-strength synthetic glass with heat-reflective properties. These glass layers are interspersed with layers of polymer-type interlayer material in a specific arrangement pattern and then subjected to a specialized heat and pressure treatment process under controlled conditions. Finally, the assembly is bonded with polycarbonate using silicone adhesive. The resulting product provides protection levels ranging from NIJ 3A, with a total glass thickness between 28 millimeters and no more than 32 millimeters, up to NIJ 3, with a total glass thickness between 33 millimeters and no more than 38 millimeters.

Description

[0001] Details of the Invention

[0002] Title of Invention

[0003] LAMINATED BULLETPROOF GLASS AND MANUFACTURING PROCESS

[0004] Field of Technology

[0005] Mechanical engineering, materials science, and processes related to bulletproof glass

[0006] Background of the Art

[0007] Currently, unrest has arisen in many areas and in various forms to achieve different goals, stemming from conflicting ideologies among multiple parties. The forms of these incidents vary, with different levels of violence, ultimately leading to loss of life and property damage. One common form of incident in areas of intense conflict that escalates into clashes is the ambush of civilians, community leaders, dignitaries, and peacekeepers with various firearms while they are on duty or engaged in activities, resulting in severe loss of life and property damage. Therefore, to prevent and mitigate damage from such incidents, bulletproof glass is a popular choice for protection.

[0008] To defend against various firearms with different levels of intensity, bulletproof glass comes in varying numbers of layers and thicknesses, as well as different types of interlayer films. When impacted by bullets or other objects, the broken pieces do not detach and maintain their original state, with only cracks appearing on the glass surface. Additionally, considering the impact force from external bullets and the safety from potential glass shards upon bullet impact, different types of film can be chosen for the inner and outer layers. Generally, regular bulletproof or laminated glass can resist revolver bullets at a distance of 1 to 30 meters. It can also prevent theft due to the difficulty of penetrating the film layers. Currently, bulletproof glass is commonly found in applications such as door windows for bulletproofing in cash transport vehicles, prisoner transport vehicles, military vehicles, teller windows at banks, VIP rooms, and windows in important embassy buildings.

[0009] Laminated glass consists of at least two glass sheets with a polymer interlayer in between to bond the two sheets together. The laminated glass manufacturing process creates chemical bonds between hydroxyl groups (polymer) and silanol groups (glass). This type of chemical bond occurs at all interlayer interfaces in the hydroxyl group, including polyvinyl butyral (PVB), thermoplastic polyurethane (TPU), ethylene-vinyl acetate (EVA), and ionomers. This composite material can significantly improve the properties of glass, both before and after breakage. Before breakage, when a laminated glass sheet is bent in-plane, the interlayer material transfers shear stress between the glass surfaces, consequently affecting the bending stiffness. The stiffer the interlayer, the higher the bending stiffness of the laminated glass sheet, and the force applied will cause cracks to appear and propagate, which can be redirected by the shear stress in the interlayer material to the adjacent unbroken glass layer. The crack blocking mechanism prevents cracks from opening up on the laminated glass sheet. Due to these adhesion properties, laminated glass has a certain level of residual strength after breakage. This is because the polymer interlayer material can provide a certain level of tensile stress while the broken glass fragments can still provide compressive stress but cannot withstand tensile stress. Laminated glass, therefore, has a higher post-breakage strength than monolithic glass, where the post-breakage strength of laminated glass depends on the strength of the polymer interlayer material, which in turn depends on its stiffness, thickness, and level of adhesion to the glass.

[0010] Due to the desired interlayer material properties of laminated glass, which are transparency and the ability to bond glass sheets, amorphous structural polymers are the most suitable choice. Interlayer polymer materials can be divided into two main groups based on the manufacturing process. The first type consists of the most common interlayer materials, bonded by a lamination process, which are sheet polymers such as polyvinyl butyral (PVB), ethylene - vinyl acetate (EVA), ionomers (e.g., Sentry Glass), thermoplastic polyurethane (TPU), polycarbonate (PC), and polyethylene terephthalate (PET). The second group is the cast-in-place (CIP) interlayer type, with polyurethane (PU), polymethyl methacrylate (PMMA), and epoxy. Although different polymer materials are used as binders in the laminated glass manufacturing process, to date, polyvinyl butyral (PVB) remains widely used in all areas of laminated glass applications due to its affordability, widespread production, and availability.

[0011] The materials used to make laminated bulletproof glass include float glass, which is highly transparent, has a smooth surface, good reflectivity, few air bubbles within the glass sheet, and a strong molecular arrangement within the glass. Float glass (annealed glass) is layered alternately with polymer-type interlayer materials having the same width and length as the glass, in a flat sheet shape. Annealed glass is a readily available material.

[0012] The interlayer material for laminated bulletproof glass consists of polymer -type interlayer materials, including general-purpose polyvinyl butyral resin (PVB). It is a polymer compound obtained from the reaction of polyvinyl alcohol and butyraldehyde under acid catalysis. It has the properties of white spherical porous particles or powder. The specific gravity is 1 to 1 at a packing density of only 0.20 to 0.35 grams per milliliter (g / ml). The heat distortion temperature ranges from 50 to 90 degrees Celsius. It is used for applications requiring strong adhesion, light clarity, adhesion to various surfaces, toughness, and flexibility. It is also waterproof, oil -resistant, safe, non-toxic, and harmless to the human body. Therefore, it is widely used in printing inks for food packaging and plastic packaging in Europe and America. This interlayer material is readily available.

[0013] The final layer uses polycarbonate (PC) in the manufacturing process to protect users from glass shards in case the glass is broken. Polycarbonate (PC) is a group of thermoplastic polymers containing carbonate groups in their chemical structure. Polycarbonates used in engineering are strong, durable, and can be easily molded and thermoformed. Polycarbonate is almost as transparent as glass and is lightweight, weighing about half as much as glass, resulting in lower transportation costs and easier handling and storage. It has good mechanical properties, strength, toughness, and impact resistance. It can also maintain good mechanical properties when exposed to high temperatures up to 140 degrees Celsius. Its operating temperature range is -20 to 140 degrees Celsius without losing mechanical properties or deforming. It is a thermal insulator, preventing heat buildup when used in sunlight. It is resistant to certain chemicals such as alcohol, weak acids, and aliphatic hydrocarbons but not resistant to bases, aromatic hydrocarbons, and halogenated hydrocarbons. It is not UV resistant, so it can easily turn yellow when used outdoors. It is also not scratch-resistant. This material is readily available.

[0014] The infrared reflective pigments with a spinel structure in the iron chromium aluminate system (Crx,Fey)A12O4 are subjected to a drying process in an electric oven to achieve the desired crystal structure. They are then ground to an appropriate particle size for infrared reflection. This process allows for the preparation of ceramic powders in large quantities, ensuring a crystal structure resistant to environmental conditions and effectively reflecting infrared radiation with wavelengths ranging from 700 to 2,500 nanometers. The material also absorbs ultraviolet radiation and visible light. Therefore, iron chromium aluminate type metal oxide ((Crx, Fey)A12O4) can be incorporated into mixtures for various applications such as exterior building paints, automotive paints, glass, plastics, or other related industries to reflect heat from infrared radiation. This results in lower temperatures inside buildings or structures, reducing air conditioning costs and extending the lifespan of materials and equipment affected by high heat.

[0015] The selection of the aforementioned materials in the laminated bulletproof glass manufacturing process, which incorporates layers of float glass or high-strength synthetic glass or high-strength synthetic glass with heat-reflective properties, and the manufacturing process itself involve choosing materials that offer high levels of protection when assembled according to the appropriate laminated glass manufacturing process. Moreover, these materials are readily available and accessible, providing flexibility in their utilization across various forms based on the manufacturer's requirements, thus enabling cost control and resource conservation during production.

[0016] The evaluation of bulletproof glass efficacy necessitates testing its bullet resistance in accordance with NIJ standards at each level. The NIJ standards pertain to the methods and criteria for assessing the bulletproof capability or performance of materials as established by the National Institute of Justice (NIJ) in the United States. The NIJ Level 3 testing for bulletproof glass involves firing 7.62x51 mm NATO FMJ 148 Gr bullets at a 0-degree angle from a distance of 15 meters. The test employs a bulletproof glass sheet measuring at least 12x12 inches (305x305 mm). The firing is conducted on one sheet at a time, repeated three times, with each instance involving five shots aimed at the four corners and the center of the sheet, at an average velocity of 847 meters per second. The desired outcome is the absence of bullet penetration after firing, irrespective of the spacing between impact points. This signifies that "the armor can withstand normal or higher threat situations." The NIJ Level 3 A testing for bulletproof glass utilizes 5.56x45 mm NATO bullets, and the testing procedure mirrors that of the NIJ Level 3 test. Previous Works

[0017] • 2014: Gyu-In Shim et al. The research focused on the fabrication of lightweight and thin bullet-resistant windows using ion-exchange strengthened borosilicate glass. The study identified the optimal ion-exchange conditions for borosilicate glass with thicknesses of 3, 4, and 6 millimeters at a temperature of 560 degrees Celsius for durations of 10, 12, and 15 minutes, respectively. The penetration depth of potassium ions into the glass was 42, 63, and 78 liters, respectively. The ion-exchange rate of potassium ions was approximately 4.9 ± 0.6 liters / minute at 560 degrees Celsius. The bending strength of the ion-exchange strengthened borosilicate glass with thicknesses of 3, 4, and 6 millimeters was 0.745 ± 0.018, 0.783 ± 0.017, and 0.810 ± 0.014 GPa, respectively, which is about 2.8 times higher than that of conventional bulletproof glass. The fracture toughness of the ion-exchanged borosilicate glass at thicknesses of 3, 4, and 6 millimeters was 0.911 ± 0.018, 0.959 ± 0.005, and 1.010 ± 0.027 MPa ml / 2, representing increases of 18%, 23%, and 29%, respectively. The Vickers hardness of the ion-exchange strengthened glass at thicknesses of 3, 4, and 6 millimeters was 6.93 ± 0.13, 7.08 ± 0.15, and 7.21 ± 0.14 GPa, respectively, an increase of up to about 27% compared to the original bulletproof glass.

[0018] • 2014: Gyu-In Shim et al. This research aimed to improve the ballistic impact resistance of bulletproof materials coated with soda-lime silicate for glass strengthening, producing lightweight and thin bulletproof materials referred to as SLS glass. Strengthening was achieved through ion exchange at 480 degrees Celsius for 10 to 20 minutes, allowing potassium ions to penetrate the SLS glass with thicknesses of 3, 4, 8, and 10 millimeters to depths of approximately 17, 21, 30, and 37 millimeters, respectively. This resulted in increased Vickers hardness and fracture toughness of 22% and 5%, respectively, compared to conventional bulletproof glass. Bending strength increased 3.5 times under optimal ion-exchange conditions. The transmittance of the strengthened glass had a minimum value of 88%, allowing it to be coated onto bulletproof glass. Using the 23GMGGPP(10) strengthened glass sample, the glass thickness was reduced from 28.65 to 23.85 millimeters, and the areal density decreased from 68.85 to 50.06 kilograms per square meter. The 23GMGGPP(10) material had a Vo of 973.8 meters per second, meeting the NI J- STD-0108.01 projectile limiting velocity (V50: 838 ± 15 meters per second). The Vo value was 14% higher than the bulletproof value. The material fabricated with SLS glass (V50: 851 meters per second) had a 10% higher bulletproof performance compared to the material strengthened with borosilicate glass (V50: 889.4 meters per second). Therefore, bulletproof materials with improved protective performance can be fabricated using SLS glass for strengthening. Finally, the transmittance of the bulletproof material strengthened with SLS glass exceeded 83.0%, which is a satisfactory criterion according to NIJ-STD- 0108.01 (77%).

[0019] • 2013: Bertolini, Alberto, Este, IT This research focused on the manufacturing process of special safety glass incorporating both UV filtering and electrochromic films, enhancing UV protection and controlling light transmission through the glass. The UV filtering film is produced by coating a liquid crystal polymer compound onto a polyurethane film or other thermoplastic material. The film is then dried and cured using UV light. This step may include adding reinforcement layers to further improve UV filtering efficiency. The electrochromic film is produced by coating an indium tin oxide (ITO) solution onto a film, followed by coating with an electrochromic compound and another layer of ITO solution. This type of film has the special property of adjusting the intensity of transmitted light. The safety glass assembly involves placing the UV filtering and electrochromic films between each glass layer, with potential variations in film arrangement. The glass layers are then laminated together using heat and pressure in a controlled-pressure oven. This process ensures a strong bond between the films and glass, enhancing the strength and safety of the safety glass. Additionally, adding a step of coating the inner surface of the glass with polyurethane and a polycarbonate sheet can further improve protection against glass breakage.

[0020] • 2013: Mario Arturo Benjamin Mannheim et al. This research explored the production of curved bulletproof glass, an innovation combining strength and flexibility. This type of bulletproof glass consists of multiple layers, including ion-exchange strengthened glass or ceramic glass layers, at least one glass or ceramic glass layer, an inner plastic layer, and an adhesive material bonding the layers together. The manufacturing process begins with cutting and shaping the glass or ceramic glass to the desired size and shape. The edges are then polished to minimize potential damage. A crucial step is bending each layer using heat and gravity to achieve the desired curved shape. Another important step is ion exchange in at least one of the glass or ceramic glass layers, enhancing flexibility and mechanical strength. Additionally, the edges of the glass are painted black to block UV rays and improve aesthetics. In the final step, the ion-exchange strengthened glass or ceramic glass layer, the inner plastic layer, and the interlayer material are laminated together and undergo another heat and pressure bending process to ensure all materials bond into a single unit, resulting in high-quality curved bulletproof glass.

[0021] • 2020: Wang Jinping et al. This research investigated bulletproof glass with special properties for radiation and electromagnetic shielding, along with the ability to generate electricity. The glass comprises 12 layers of various materials stacked together, including metal foil layers, two vacuum layers, a heat-reflective layer, three glass layers, three film layers, a copper mesh layer, and a power generation layer. The manufacturing process begins with coating a heat-reflective film and an anti-reflective film on a glass sheet using a sputtering machine for the heat-reflective film and gel injection and heat treatment at 500 degrees Celsius. Then, the power generation layer is assembled by layering materials such as glass sheets, transparent conductive films, window layers, absorption layers, back contact layers, and back electrode layers, and placing them in a vacuum coating machine. Afterward, the layers are assembled into bulletproof glass, with a PVC frame installed and desiccant added to create a vacuum layer, enhancing sound and heat insulation. The final step is sealing the glass edges with sealant to prevent air and moisture leakage. Test results showed that the bulletproof glass could reduce noise by up to 30 decibels. It also had a 13% solar energy to electricity conversion efficiency, a thermal conductivity of 1.6 watts per square meter-Kelvin, and could reduce UV radiation by up to 6 volts per meter.

[0022] • 2022: FABIO MOREIRA SANTOS This research focused on the manufacturing process of bulletproof glass using a material called "F4 (TRI -LAYERS)", consisting of three film layers. The bulletproof glass made with F4 (TRI -LAYERS) starts with cleaning the glass sheets with glass cleaner, rinsing with clean water, and drying with a microfiber cloth to prepare the surface for F4 coating. Then, F4 material is prepared by mixing resins A and B in a 1 : 1 ratio and resins C and D in a 1 : 1 ratio as well. Once both mixtures are obtained, they are mixed together in a 1 : 1 ratio and stirred until homogeneous. The F4 mixture is then coated onto the first glass sheet, spread evenly with a roller to a thickness of 0.5 millimeters to ensure uniform coverage. Another glass sheet is then placed on top of the first, and a roller is used to remove air bubbles, ensuring tight lamination without air gaps. The laminated glass is then baked in a hot air oven at 60 degrees Celsius for 24 hours to allow the F4 to set and adhere firmly to the glass sheets. The F4 coating and drying steps are repeated to achieve a total of three F4 layers on the glass, enhancing strength and impact resistance. Finally, the glass with three F4 layers is subjected to a final drying process for 48 hours to ensure complete F4 drying, and its quality is checked through shooting and impact tests.

[0023] • 2011: Pinkney, Linda Earl et al. delves into the manufacturing process of transparent laminated glass made from ceramic glass and glass. It commences with the preparation of at least one transparent ceramic glass sheet and one transparent glass sheet. The ceramic glass possesses unique properties, including a higher melting point than conventional glass and superior heat resistance. The transparent glass contributes to the overall transparency and aesthetic appeal of the final product. The subsequent step involves arranging the glass sheets onto the ceramic glass sheet, ensuring they are in close contact. The arranged assembly is then placed in a furnace and heated to the appropriate temperature, exceeding the softening point of glass but remaining below the melting point of ceramic glass, typically ranging from 600 to 800 degrees Celsius. The meticulous control of temperature during this stage is paramount, as it allows the glass sheets to melt and seamlessly bond with the ceramic glass sheet without causing any deformation to the ceramic glass itself. Once the glass and ceramic glass sheets have fused into a unified entity, the bonded material is gradually cooled down to room temperature. The cooling process holds equal significance, as a rapid reduction in temperature could induce internal stresses within the material, potentially leading to fractures in the laminated sheet. The culmination of the manufacturing process yields a transparent laminated glass sheet crafted from ceramic glass and glass, showcasing enhanced strength, impact resistance, and heat resistance compared to ordinary glass. Furthermore, the process allows for the incorporation of a debris capture layer, typically fashioned from polycarbonate, into the laminated glass, augmenting its strength and safeguarding against shattering upon impact. This innovation mitigates the necessity for polymer interlayers or adhesives between the glass layers, which are prone to deterioration over time.

[0024] • 2013: Thilo Zachau, Bensheim et al. The research focused on the manufacturing process of transparent ceramic glass sheets from lithium aluminosilicate (LAS), starting with selecting high-purity materials consisting of lithium oxide (LioO), aluminum oxide (AI2O3), and silicon oxide (SiOo) in appropriate proportions. After mixing the materials, other substances may be added, such as fluxing agents or colorants, to achieve desired properties. The mixture is then melted in a furnace at 1 ,500 to 1,600 degrees Celsius until it becomes a homogeneous, transparent molten glass. The next step is forming, which can be done in several ways, such as rolling the molten glass on a flat surface to obtain a sheet of uniform thickness or casting the molten glass into a mold to achieve the desired shape. After forming, the glass is slowly cooled to prevent internal stresses that could cause breakage. Additionally, there's an annealing step involving heating the glass at 500 to 600 degrees Celsius to relieve any stresses that might have arisen during cooling. The final step is ceramization, transforming the glass structure into ceramic by heating the glass at high temperatures in two stages. The first stage heats the glass at about 750 degrees Celsius for 20 minutes to stimulate the formation of crystal nuclei, initiating the structural change from glass to ceramic. The second stage increases the temperature to 900 degrees Celsius, holding it for 20 minutes to allow the formed crystals to grow into a complete ceramic structure. The temperature of the resulting ceramic glass sheet is then slowly reduced to room temperature. After completing these processes, a transparent ceramic glass sheet is obtained, exhibiting strength, impact resistance, and a low coefficient of thermal expansion.

[0025] • 2016: HE KAICHENG et al. This research focused on manufacturing glass capable of absorbing UV and infrared radiation. The process begins with preparing the glass mixture, consisting of main components providing hardness and transparency, such as silicon dioxide (SiC ), the primary component of ordinary glass; sodium oxide (Na2O), which lowers the melting temperature of the glass for easier manufacturing; calcium oxide (CaO) to enhance strength and chemical resistance; and aluminum oxide (AI2O3), which improves mechanical strength and high-temperature resistance. Other compounds are also added, such as magnesium oxide (MgO), potassium oxide (K2O), barium oxide (BaO), and sulfur trioxide (SO3) to tailor the glass properties for specific applications. The key components enabling UV and infrared absorption are iron (III) oxide (FeoCh), which can absorb both UV and near-infrared radiation; zirconium dioxide (ZrCT) and hafnium dioxide (Hf’Ch), which effectively absorb UV radiation; and titanium dioxide (TiCU), which, in addition to UV absorption, increases the refractive index, making the glass more lustrous. Other components like chlorine (Cl), boron trioxide (B2O3), copper (II) oxide (CuO), bromine (Br), manganese (II) oxide (MnO), fluorine (F), strontium oxide (SrO), and cerium (IV) oxide (CeO2) also contribute to UV and infrared absorption. Preparing this glass mixture requires controlling the oxidation -reduction ratio of iron (III) oxide (Fe2O3) within the range of 0.4 to 0.8 for optimal radiation absorption. The mixture is then melted in a furnace at 15,00 to 1,600 degrees Celsius to ensure homogeneity and eliminate air bubbles. The molten glass is then formed into the desired product, such as glass sheets or panels. This can be achieved by pouring the glass onto a flat surface and using a roller to achieve the desired thickness or by pouring the glass into molds of the desired shape. Once the product is formed, it undergoes annealing in an oven at a temperature slightly below the melting point, with a gradual decrease in temperature to reduce internal stresses arising during forming, enhancing the glass's strength and fracture resistance. The final step involves quality control using a spectrophotometer to measure the amount of UV and infrared radiation the glass can absorb, along with other properties like visible light transmittance, strength, scratch resistance, and chemical resistance.

[0026] • 2014: Boone, Lionel The research focused on translucent lithium aluminosilicate (LAS) ceramic glass with beta-quartz solid solution as the main crystal phase. The chemical composition was modified by reducing lithium oxide (Li2O) content to no more than 3.3% by weight. This reduction offers several benefits, such as lowering production costs due to the high price of lithium. It also simplifies the manufacturing process, as Li2O affects the viscosity of molten glass, making it harder to control in large quantities. In addition to reducing Li2O, cobalt oxide (CoO) and iron (III) oxide (Fe2O3) were used as colorants instead of vanadium oxide (V2O5), a common but more expensive colorant in ceramic glass. Using CoO and Fe2O3 reduces production costs and simplifies the process. The developed ceramic glass is transparent with a low coefficient of thermal expansion and good light transmittance. The composition includes silicon dioxide (SiO2) 60 to 67.5%, aluminum oxide (AI2O3) 18-22%, lithium oxide (LioO) 2.5 to 3.3%, magnesium oxide (MgO) 0 to 1.5%, zinc oxide (ZnO) 1 to 3.5%, barium oxide (BaO) 0 to 4%, strontium oxide (SrO) 0 to 4%, calcium oxide (CaO) 0 to 2%, titanium dioxide (TiCU) 3.1 to 5%, zirconium dioxide (ZrCh) 0.4 to 1.3%, sodium oxide (NaoO) 0 to 1%, potassium oxide (K2O) 0 to 1%, phosphorus pentoxide (P2O5) 0 to 3%, cobalt (II) oxide (CoO) 0.02 to 0.1%, iron (III) oxide (Fe2O3) 0.05 to 0.25%, and optionally at least one refining agent up to 2%, with the condition that (0.74MgO + 0.19BaO + 0.29SrO + 0.53CaO + 0.48Na2O + O.32K2O) / Li2O < 0.8. The ceramic glass, according to the aforementioned composition, has a coefficient of thermal expansion between 25 and 700 degrees Celsius in the range of ±14x 107per Kelvin and exhibits excellent melting properties, with a liquidus temperature below 1,400 degrees Celsius and a viscosity exceeding 400 Pascal -seconds or a viscosity of 30 Pascal-seconds at a temperature not exceeding 1 ,640 degrees Celsius. It also has an electrical resistivity at a viscosity of 30 Pascal -seconds lower than 50 ohms per centimeter.

[0027] • US Pat. No. 2021 / 0379871 Al This patent describes a transparent bulletproof glass with anti-shatter properties and a fire-resistant coating. It comprises at least two layers of transparent sheets with an intermediate bonding layer, each layer having a thickness of at least 3 millimeters. The fire protection part is constructed from two layers of transparent sheets bonded together with a transparent interlayer, maintaining a distance between the bulletproof and fire-resistant layers, with both layers perfectly parallel.

[0028] • US Pat. No. 10,239,288 B2 This invention relates to the construction of glass panes, specifically bulletproof glass panes for automotive use. It involves multiple layers of transparent glass panes stacked together, made of materials such as glass, ceramic, or synthetic materials, laminated together. It incorporates an electrically controlled electrochromic layer for light transmission control, which is transparent and can filter UV radiation.

[0029] • US Pat. No. 9,950,944 B2 This patent describes a curved composite bulletproof glass comprising mechanically curved and ion-exchange strengthened glass or glass-ceramic, with an inner plastic layer. The layers are bonded together with at least one layer of interlayer material. The bullet impact layer is glass or glass-ceramic, and the plastic layer is internal. • US Pat. No. 2021 / 0379871 Al The research pertains to the development of transparent bulletproof glass that possesses anti-shatter properties and is coated with a fire-resistant substance. The glass comprises at least two layers of transparent sheets, each with a minimum thickness of 3 millimeters, joined together by an intermediate bonding layer. The fire-resistant component is constructed by laminating two layers of transparent sheets with a transparent bonding layer, maintaining a specific distance between the bulletproof and fire-resistant layers, ensuring they are perfectly parallel.

[0030] • US Pat. No. 10,239,288 B2 The research presented in this patent involves the creation of glass panes, particularly bulletproof glass panes for automotive applications. It features multiple layers of transparent glass panes stacked together, crafted from materials like glass, ceramic, or synthetic materials, and laminated together. The invention incorporates an electrically controlled electrochromic layer for regulating light transmission, which is transparent and capable of filtering UV radiation.

[0031] Currently, bulletproof glass is being developed by manufacturers, researchers, and developers through various processes and methods, and it is being produced and sold in the market in many regions and areas. However, access to such materials is highly restricted, both in terms of market conditions and the policies of each region, making it difficult for those who need them to readily access these materials, especially in areas experiencing intense conflict, such as wars that have occurred at various times, resulting in barriers to accessing such materials.

[0032] Therefore, the developers recognize the importance of protecting the lives and property of all individuals. They have conducted research and development on laminated bulletproof glass that incorporates layers of float glass, high-strength synthetic glass, or high-strength synthetic glass with heat-reflective properties, and a manufacturing process that utilizes materials with a high level of protection against bullet attacks. The development of these materials is based on the concept of increasing accessibility and opportunities for users to access such materials by selecting commonly available materials and employing simple manufacturing processes that reduce complexity or control conditions. The selection of machinery in the production process also emphasizes ease of use, with various layer arrangements and material choices to provide manufacturers with more options for creating such materials, all while considering cost reduction in production. These factors are crucial in the design, research, and development to create innovations that can be further developed commercially.

[0033] The Nature and Objectives of the Invention

[0034] The nature and objectives of this invention are to design laminated bulletproof glass that incorporates layers of float glass, high-strength synthetic glass, or high-strength synthetic glass with heat-reflective properties. These glass layers are arranged alternately with polymer-type interlayer materials in a specific layer arrangement pattern and undergo a specific heat and pressure treatment process under controlled conditions. The resulting assembly is then bonded with polycarbonate using silicone adhesive. The aim is to achieve protection levels of NIJ 3A, with a total glass thickness ranging from 28 millimeters to no more than 32 millimeters, and up to NIJ 3, with a total glass thickness ranging from 33 millimeters to no more than 38 millimeters, offering high protection against attacks. The invention also seeks to minimize the thickness and weight of the bulletproof glass sheet as much as possible to reduce the weight burden and internal temperature, which can impact installation efficiency, while taking into account production cost reduction to enhance accessibility and opportunities for users to obtain such materials.

[0035] Brief Description of the Drawings

[0036] Figure 1: The arrangement pattern between the glass and the polymer-type interlayer material, using 3 layers of glass.

[0037] Figure 2: The arrangement pattern between the glass and the polymer-type interlayer material, using 4 layers of glass.

[0038] Figure 3: The arrangement pattern between the glass and the polymer-type interlayer material, using 5 layers of glass.

[0039] Figure 4: The arrangement pattern between the glass and the polymer-type interlayer material, using 7 layers of glass. Complete disclosure of invention

[0040] The laminated bulletproof glass comprises layers of float glass (1), or high-strength synthetic glass (1A), or high-strength synthetic glass with heat -reflective properties (IB), or polymer-type interlayer material (2). The glass and interlayer materials are arranged alternately in a specific layer configuration and subjected to a specific heat and pressure treatment process under controlled conditions. The resulting assembly is then bonded with polycarbonate (3) using silicone adhesive.

[0041] Wherein the high-strength synthetic glass (1A) has the following manufacturing process

[0042] 1. Preparation of Magnesium Aluminate (MgAhCM) Powder

[0043] 1.1 Magnesium carbonate (MgCCh) powder and aluminum oxide (AI2O3) powder are used as starting materials. These are mixed together by wet mixing in water at a molar ratio of 1 : 1 using a ball mill for 24 hours.

[0044] 1.2 The mixed powder from step 1.1 is dried in an electric oven at 100 degrees Celsius for at least 24 hours until the moisture content in the powder is less than 12% RH.

[0045] 1.3 The mixed powder from step 1.2 is placed in an electric furnace at a temperature of 1,300 to 1,500 degrees Celsius for 2 to 5 hours. It is then ground with a ball mill to separate the agglomerated particles of the mixed powder. This yields magnesium aluminate (MgAhCM) powder, which is then packaged in a closed container and stored in an environment with a temperature range of 25 to 30 degrees Celsius.

[0046] 2. Preparation of High-Strength Synthetic Glass

[0047] 2.1 Dry mix lithium tetraborate (Li2B4O?) powder with the magnesium aluminate (MgAhCM) powder obtained from the preparation in step 1 at a molar ratio of 2: 1 using a ball mill for 6 hours. 2.2 Place the mixed powder from step 2.1 into a graphite crucible and place it in an electric furnace. Heat at a rate of 3 to 8 degrees Celsius per minute until the temperature reaches 1,100 degrees Celsius and hold for 1 hour.

[0048] 2.3 From step 2.2, open the furnace and remove the graphite crucible using tongs. Pour the molten glass from the crucible into a mold and press the molten glass to fit the mold. Then allow it to cool. This will result in high-strength synthetic glass, which has a hardness greater than ordinary glass, with translucent properties that allow light to pass through more than 90%.

[0049] And the high-strength synthetic glass with heat -reflective properties (IB) has the following manufacturing process

[0050] 1. Preparation of Heat-Reflective Material, Iron Chromium Aluminate ((Crx, Fey)A12O4)

[0051] 1.1 Iron oxide (Fe) and chromium oxide (Cr) are mixed with aluminum oxide (Al). The ratio of the three components is determined from the chemical formula of the spinel structure (Crx, Fey)A12O4. The molar ratio between iron oxide, chromium oxide, and aluminum oxide is 0.5 to 1.5 : 0.5 to 1.5 : 1.5 to 2.5.

[0052] 1.2 The three materials are wet mixed in water at the ratio from step 1.1 using a ball mill for 6 hours.

[0053] 1.3 The mixed material from step 1.2 is dried in an electric oven at 105 degrees Celsius for more than 24 hours until the moisture content in the powder is less than 12% RH.

[0054] 1.4 The mixed material from step 1.3 is placed in an electric furnace at a temperature of 1,500 to 1,700 degrees Celsius for 2 to 20 hours.

[0055] 1.5 The synthesized material from step 1.4 is ground using a ring mill for 3 to 12 minutes. This yields heat reflective material, iron chromium aluminate ((Crx, Fey)AhO4).

[0056] 2. Preparation of High-Strength Synthetic Glass with Heat-Reflective Properties 2.1 Mix lithium tetraborate (I^E O?) with magnesium aluminate (MgAhCM) at a molar ratio of 2: 1. Then add 1 to 5 mol% of iron chromium aluminate ((Crx, Fey)A12O4) and mix thoroughly using a ball mill for 6 hours.

[0057] 2.2 Place the mixture from step 2.1 into a graphite crucible and place it in an electric furnace. Heat at a rate of 3 to 8 degrees Celsius per minute until the temperature reaches 1,100 degrees Celsius and hold for 1 hour.

[0058] 2.3 From step 2.2, open the electric furnace and remove the graphite crucible. The glass will be in a molten state inside the crucible. Pour the molten glass into a mold and press it to fit the mold. Then allow it to cool. This will result in high-strength synthetic glass with heat-reflective properties, allowing more than 80% of light to pass through.

[0059] From Figure 1 to Figure 4, the laminated bulletproof glass, which comprises layers of float glass (1) or high-strength synthetic glass (1A) or high-strength synthetic glass with heat -reflective properties (IB) or polymer-type interlayer material (2), where these glass and interlayer materials are arranged alternately in a specific layer configuration, has the layer arrangement details as specified in Table 1 and Table 2.

[0060] Table 1: Layer arrangement of laminated bulletproof glass incorporating float glass (1), high- strength synthetic glass (1 A), or high-strength synthetic glass with heat-reflective properties (IB), at NIJ 3A level (unit: millimeters)

[0061] Layer Layer Layer Layer

[0062] Config Layer 1 Layer 2 Layer 3 Layer 4 Layer 5 Layer 6 Layer ? Layer s Layer 9 LayerlO 11 12 13 14

[0063] 1 Glass PVB Glass PVB Glass PC

[0064] 12.0 0.5-1.5 8.0 0.5-1.5 4.0 3.0

[0065] 2 Glass PVB Glass PVB Glass PC

[0066] 15.0 0.5-1.0 6.0 0.5-1.0 6.0 3.0

[0067] 0 . 5 -

[0068] 3.0 0.5-1.0 3.0 0.5-1.0 3.0 0.5-1.0 3.0 0.5-1.0 3.0 0.5-1.0 6.0 3.0 3.0

[0069] 1.0

[0070] Group 1: Laminated bulletproof glass composed of layers of float glass (1), high-strength synthetic glass (1A), or high-strength synthetic glass with heat -reflective properties (IB), or polymer-type interlayer material (2), where the glass and interlayer materials are arranged alternately in a specific layer configuration. There are 3 specific layer arrangement patterns:

[0071] • According to Figure 1 , the layers are arranged in a specific pattern with a total thickness ranging from 28 to 32 millimeters. It uses 3 layers of glass. Group 1, Pattern 1 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 12.0 millimeters. o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters. o Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters. o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters. o Layer 5: Float glass (1) layer 3, with a thickness of 4.0 millimeters. • According to Figure 1 , the layers are arranged in a specific pattern with a total thickness ranging from 28 to 32 millimeters. It uses 3 layers of glass. Group 1, Pattern 2 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 15.0 millimeters. o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 3: Float glass (1) layer 2, with a thickness of 6.0 millimeters. o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 5: Float glass (1) layer 3, with a thickness of 6.0 millimeters.

[0072] • According to Figure 4, the layers are arranged in a specific pattern with a total thickness ranging from 28 to 32 millimeters. It uses 7 layers of glass. Group 1, Pattern 3 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 3.0 millimeters o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters o Layer 3: Float glass (1) layer 2, with a thickness of 3.0 millimeters o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters o Layer 5: Float glass (1) layer 3, with a thickness of 3.0 millimeters o Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters o Layer 7: Float glass (1) layer 4, with a thickness of 3.0 millimeters o Layer 8: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters o Layer 9: Float glass (1) layer 5, with a thickness of 3.0 millimeters o Layer 10: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters o Layer 11: Float glass (1) layer 6, with a thickness of 6.0 millimeters o Layer 12: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters o Layer 13: Float glass (1) layer 7, with a thickness of 3.0 millimeters

[0073] Table 2. Layer arrangement of laminated bulletproof glass incorporating float glass (1), high- strength synthetic glass (1 A), or high-strength synthetic glass with heat-reflective properties (IB), at NIJ 3 level (unit: millimeters)

[0074] Layer Layer Layer Layer Layer Layer Layer Layer Layer Layer Layer Layer Layer Layer Config

[0075] 1 2 3 4 5 6 7 8 9 10 11 12 13 14

[0076] 1 Glass PVB Glass PVB Glass PC

[0077] 0.5- 0.5-

[0078] 6.0 10.0 10.0 6.0

[0079] 2.0 2.0

[0080] 2 Glass PVB Glass PVB Glass PVB Glass PC

[0081] 8.0 0. 5 - 8.0 0.5 - 8.0 0.5 - 6.0 6.0

[0082] 1.0 1.0 1.0

[0083] 3 Glass PVB Glass PVB Glass PVB Glass PVB Glass PC

[0084] 0.5- 0.5- 0.5- 0.5 -

[0085] 3.0 8.0 8.0 8.0 3.0 3.0

[0086] 1.5 1.5 1.0 1.0

[0087] 4 Glass PVB Glass PVB Glass PVB Glass PVB Glass PVB Glass PVB Glass PC

[0088] 0.5- 0.5- 0.5- 0.5 - 0.5- 0.5-

[0089] 3.0 8.0 8.0 3.0 3.0 3.0 3.0 3.0

[0090] 1.0 1.0 1.0 1.0 1.0 1.0

[0091] Group 2: Laminated bulletproof glass composed of layers of float glass (1), high-strength synthetic glass (1A), or high-strength synthetic glass with heat -reflective properties (IB), or polymer-type interlayer material (2), where the glass and interlayer materials are arranged alternately in 4 specific layer arrangement patterns: • According to Figure 1 , the layers are arranged in a specific pattern with a total thickness ranging from 33 to 38 millimeters. It uses 3 layers of glass. Group 2, Pattern 1 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 6.0 millimeters. o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 2.0 millimeters. o Layer 3: Float glass (1) layer 2, with a thickness of 10.0 millimeters. o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 2.0 millimeters. o Layer 5: Float glass (1) layer 3, with a thickness of 10.0 millimeters.

[0092] • According to Figure 2, the layers are arranged in a specific pattern with a total thickness ranging from 33 to 38 millimeters. It uses 4 layers of glass. Group 2, Pattern 2 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 8.0 millimeters. o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters. o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 5: Float glass (1) layer 3, with a thickness of 8.0 millimeters. o Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 7: Float glass (1) layer 4, with a thickness of 6.0 millimeters.

[0093] • According to Figure 3, the layers are arranged in a specific pattern with a total thickness ranging from 33 to 38 millimeters. It uses 5 layers of glass. Group 2, Pattern 3 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 3.0 millimeters. o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters. o Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters. o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters. o Layer 5: Float glass (1) layer 3, with a thickness of 8.0 millimeters. o Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 7: Float glass (1) layer 4, with a thickness of 8.0 millimeters. o Layer 8: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 9: Float glass (1) layer 5, with a thickness of 3.0 millimeters.

[0094] • According to Figure 4, the layers are arranged in a specific pattern with a total thickness ranging from 33 to 38 millimeters. It uses 7 layers of glass. Group 2, Pattern 4 is as follows: o Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high-strength synthetic glass with heat -reflective properties (IB) layer 1, with a thickness of 3.0 millimeters. o Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters. o Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 5: Float glass (1) layer 3, with a thickness of 8.0 millimeters. o Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 7: Float glass (1) layer 4, with a thickness of 3.0 millimeters. o Layer 8: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 9: Float glass (1) layer 5, with a thickness of 3.0 millimeters. o Layer 10: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 11: Float glass (1) layer 6, with a thickness of 3.0 millimeters. o Layer 12: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters. o Layer 13: Float glass (1) layer 7, with a thickness of 3.0 millimeters.

[0095] The manufacturing process of laminated bulletproof glass, which incorporates a polymer interlayer material (2) and has a specific layer arrangement pattern, involves the following steps:

[0096] Step 1: Arrange the glass and interlayer material layers according to the specific layer arrangement pattern as described in claims 2-8.

[0097] Step 2: Place the arranged glass assembly from step 1 into a leak -proof bag and vacuum out the air to create a vacuum inside the bag.

[0098] Step 3: Place the bag containing the glass from step 2 into a double-sided press machine capable of controlling temperature and pressure. Apply pressure in the range of 95 to 110 kilograms per square centimeter and increase the temperature by 5 degrees Celsius every 1 minute from room temperature until it reaches 90 to 110 degrees Celsius. Maintain this temperature for 30 minutes. Then, increase the temperature by 5 degrees Celsius every 1 minute until it reaches 120 to 130 degrees Celsius. Maintain this temperature for 120 minutes. Further increase the temperature by 5 degrees Celsius every 1 minute until it reaches 156 to 165 degrees Celsius and maintain for 180 minutes. Stop heating and reduce the pressure to allow the glass to cool down slowly until its temperature drops below 50 degrees Celsius. Then, remove it from the machine and let it cool down further.

[0099] Step 4: Place the bag containing the glass from step 3 back into the double -sided press machine capable of controlling temperature and pressure. Apply pressure in the range of 95 to 110 kilograms per square centimeter and increase the temperature by 5 degrees Celsius every 1 minute from room temperature until it reaches 155 to 165 degrees Celsius. Maintain this temperature for 180 minutes. Stop heating and reduce the pressure to allow the glass to cool down slowly until its temperature drops below 50 degrees Celsius. Then, remove it from the machine and let it cool down further. Step 5: Place the bag containing the glass from step 4 into an oven capable of controlling temperature. Increase the temperature by 3 degrees Celsius every 1 minute from room temperature until it reaches 160 to 170 degrees Celsius. Maintain this temperature for 240 minutes. Stop heating to allow the glass to cool down slowly until its temperature drops below 50 degrees Celsius. Then, remove it from the oven and let it cool down further.

[0100] Step 6: Remove the glass from the bag from step 5 and laminate it with polycarbonate (3) with a thickness of 3 to 6 millimeters as the final layer. Bond them together using silicone adhesive and let it dry completely.

[0101] The laminated bulletproof glass, as described, can be used in vehicles, buildings, counters, bulletproof shields, or any desired areas to resist penetration from bullets or other high-impact objects, thereby enhancing safety for users.

[0102] The best methods for crafting

[0103] The best method of invention is the method described in the details of the complete disclosure of the invention.

Claims

Claim1. The laminated bulletproof glass comprises layers of float glass (1), or high-strength synthetic glass (1A), or high-strength synthetic glass with heat-reflective properties (IB), or polymer- type interlayer material (2). The glass and interlayer materials are arranged alternately in a specific layer configuration and subjected to a specific heat and pressure treatment process under controlled conditions. The resulting assembly is then bonded with polycarbonate (3) using silicone adhesive.Wherein the high-strength synthetic glass (1A) has the following manufacturing process1. Preparation of Magnesium Aluminate (Mg Al 2O4) Powder1.1 Magnesium carbonate (MgCCh) powder and aluminum oxide (AI2O3) powder are used as starting materials. These are mixed together by wet mixing in water at a molar ratio of 1 : 1 using a ball mill for 24 hours.1.2 The mixed powder from step 1.1 is dried in an electric oven at 100 degrees Celsius for at least 24 hours until the moisture content in the powder is less than 12% RH.1.3 The mixed powder from step 1.2 is placed in an electric furnace at a temperature of 1,300 to 1,500 degrees Celsius for 2 to 5 hours. It is then ground with a ball mill to separate the agglomerated particles of the mixed powder. This yields magnesium aluminate (MgAhCri) powder, which is then packaged in a closed container and stored in an environment with a temperature range of 25 to 30 degrees Celsius.

2. Preparation of High-Strength Synthetic Glass2.1 Dry mix lithium tetraborate (Li2B4O?) powder with the magnesium aluminate (Mg AI2O4) powder obtained from the preparation in step 1 at a molar ratio of 2: 1 using a ball mill for 6 hours.2.2 Place the mixed powder from step 2.1 into a graphite crucible and place it in an electric furnace. Heat at a rate of 3 to 8 degrees Celsius per minute until the temperature reaches 1,100 degrees Celsius and hold for 1 hour.2.3 From step 2.2, open the furnace and remove the graphite crucible using tongs. Pour the molten glass from the crucible into a mold and press the molten glass to fit the mold. Then allow it to cool. This will result in high-strength synthetic glass, which has a hardness greater than ordinary glass, with translucent properties that allow light to pass through more than 90%.And the high-strength synthetic glass with heat -reflective properties (IB) has the following manufacturing process1. Preparation of Heat-Reflective Material, Iron Chromium Aluminate ((Crx, Fey)AhO4)1.1 Iron oxide (Fe) and chromium oxide (Cr) are mixed with aluminum oxide (Al). The ratio of the three components is determined from the chemical formula of the spinel structure (Crx, Fey)A12O4. The molar ratio between iron oxide, chromium oxide, and aluminum oxide is 0.5 to 1.5 : 0.5 to 1.5 : 1.5 to 2.5.1.2 The three materials are wet mixed in water at the ratio from step 1.1 using a ball mill for 6 hours.1.3 The mixed material from step 1.2 is dried in an electric oven at 105 degrees Celsius for more than 24 hours until the moisture content in the powder is less than 12% RH.1.4 The mixed material from step 1.3 is placed in an electric furnace at a temperature of 1,500 to 1,700 degrees Celsius for 2 to 20 hours.1.5 The synthesized material from step 1.4 is ground using a ring mill for 3 to 12 minutes. This yields heat reflective material, iron chromium aluminate ((Crx, Fe^^AhCM).

2. Preparation of High-Strength Synthetic Glass with Heat-Reflective Properties2.1 Mix lithium tetraborate (U2B4O7) with magnesium aluminate (MgAhCM) at a molar ratio of 2:

1. Then add 1 to 5 mol% of iron chromium aluminate ((Crx, Fey)A12O4) and mix thoroughly using a ball mill for 6 hours.2.2 Place the mixture from step 2.1 into a graphite crucible and place it in an electric furnace. Heat at a rate of 3 to 8 degrees Celsius per minute until the temperature reaches 1,100 degrees Celsius and hold for 1 hour.2.3 From step 2.2, open the electric furnace and remove the graphite crucible. The glass will be in a molten state inside the crucible. Pour the molten glass into a mold and press it to fit the mold. Then allow it to cool. This will result in high-strength synthetic glass with heat -reflective properties, allowing more than 80% of light to pass through.

2. The laminated bulletproof glass as claimed in claim 1 , wherein the specific layer arrangement pattern is Group 1, laminated bulletproof glass, NIJ 3 A level, Pattern 1, with a total thickness ranging from 28 to 32 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 12.0 millimeters.• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters.• Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters.• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters.• Layer 5: Float glass (1) layer 3, with a thickness of 4.0 millimeters.

3. The laminated bulletproof glass as claimed in claims 1 to 2, wherein the specific layer arrangement pattern is Group 1, laminated bulletproof glass, NIJ 3 A level, Pattern 2, with a total thickness ranging from 28 to 32 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 15.0 millimeters.• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 3: Float glass (1) layer 2, with a thickness of 6.0 millimeters.• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 5: Float glass (1) layer 3, with a thickness of 6.0 millimeters.

4. The laminated bulletproof glass as claimed in claim 1 or 3, wherein the specific layer arrangement pattern is Group 1, laminated bulletproof glass, NIJ 3 A level, Pattern 3, with a total thickness ranging from 28 to 32 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 3.0 millimeters• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters• Layer 3: Float glass (1) layer 2, with a thickness of 3.0 millimeters• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters• Layer 5: Float glass (1) layer 3, with a thickness of 3.0 millimeters• Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters• Layer 7: Float glass (1) layer 4, with a thickness of 3.0 millimeters• Layer 8: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters• Layer 9: Float glass (1) layer 5, with a thickness of 3.0 millimeters• Layer 10: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters• Layer 11: Float glass (1) layer 6, with a thickness of 6.0 millimeters• Layer 12: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters• Layer 13: Float glass (1) layer 7, with a thickness of 3.0 millimeters5. The laminated bulletproof glass as claimed in any one of claims 1 to 4, wherein the specific layer arrangement pattern is Group 2, laminated bulletproof glass, NIJ 3 level, Pattern 1, witha total thickness ranging from 33 to 38 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 6.0 millimeters.• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 2.0 millimeters.• Layer 3: Float glass (1) layer 2, with a thickness of 10.0 millimeters.• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 2.0 millimeters.• Layer 5: Float glass (1) layer 3, with a thickness of 10 millimeters.

6. The laminated bulletproof glass as claimed in any one of claims 1 to 5, wherein the specific layer arrangement pattern is Group 2, laminated bulletproof glass, NIJ 3 level, Pattern 2, with a total thickness ranging from 33 to 38 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 8.0 millimeters.• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters.• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 5: Float glass (1) layer 3, with a thickness of 8.0 millimeters.• Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 7: Float glass (1) layer 4, with a thickness of 6.0 millimeters.

7. The laminated bulletproof glass as claimed in any one of claims 1 to 6, wherein the specific layer arrangement pattern is Group 2, laminated bulletproof glass, NIJ 3 level, Pattern 3, with a total thickness ranging from 33 to 38 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 3.0 millimeters.• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters.• Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters.• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.5 millimeters.• Layer 5: Float glass (1) layer 3, with a thickness of 8.0 millimeters.• Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 7: Float glass (1) layer 4, with a thickness of 8.0 millimeters.• Layer 8: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 9: Float glass (1) layer 5, with a thickness of 3.0 millimeters.

8. The laminated bulletproof glass as claimed in any one of claims 1 to 7, wherein the specific layer arrangement pattern is Group 2, laminated bulletproof glass, NIJ 3 level, Pattern 4, with a total thickness ranging from 33 to 38 millimeters, has the following arrangement of glass and interlayer materials in its assembly:• Layer 1: Float glass (1) layer 1, or high-strength synthetic glass (1A) layer 1, or high- strength synthetic glass with heat-reflective properties (IB) layer 1, with a thickness of 3.0 millimeters.• Layer 2: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 3: Float glass (1) layer 2, with a thickness of 8.0 millimeters.• Layer 4: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 5: Float glass (1) layer 3, with a thickness of 8.0 millimeters.• Layer 6: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 7: Float glass (1) layer 4, with a thickness of 3.0 millimeters.• Layer 8: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 9: Float glass (1) layer 5, with a thickness of 3.0 millimeters.• Layer 10: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 11: Float glass (1) layer 6, with a thickness of 3.0 millimeters.• Layer 12: Polymer-type interlayer material (2), with a thickness of 0.5 to 1.0 millimeters.• Layer 13: Float glass (1) layer 7, with a thickness of 3.0 millimeters.

9. The manufacturing process of laminated bulletproof glass, which incorporates a polymer interlayer material (2) and has a specific layer arrangement pattern as defined in any one of claims 1 to 8, involves the following steps:• Step 1 : Arrange the glass and interlayer material layers according to the specific layer arrangement pattern as described in claims 2-8.• Step 2: Place the arranged glass assembly from step 1 into a leak -proof bag and vacuum out the air to create a vacuum inside the bag.• Step 3: Place the bag containing the glass from step 2 into a double -sided press machine capable of controlling temperature and pressure. Apply pressure in the range of 95 to 110 kilograms per square centimeter and increase the temperature by 5 degrees Celsius every 1 minute from room temperature until it reaches 90 to 110 degrees Celsius. Maintain this temperature for 30 minutes. Then, increase the temperature by 5 degrees Celsius every 1 minute until it reaches 120 to 130 degrees Celsius. Maintain this temperature for 120 minutes. Further increase the temperature by 5 degrees Celsius every 1 minute until it reaches 156 to 165 degrees Celsius and maintain for 180 minutes. Stop heating and reduce the pressure to allow the glass to cool down slowly until its temperature drops below 50 degrees Celsius. Then, remove it from the machine and let it cool down further.• Step 4: Place the bag containing the glass from step 3 back into the double -sided press machine capable of controlling temperature and pressure. Apply pressure in the range of 95 to 110 kilograms per square centimeter and increase the temperature by 5 degrees Celsius every 1 minute from room temperature until it reaches 155 to 165 degrees Celsius. Maintain this temperature for 180 minutes. Stop heating and reduce the pressure to allow the glass to cool down slowly until its temperature drops below 50 degrees Celsius. Then, remove it from the machine and let it cool down further.• Step 5: Place the bag containing the glass from step 4 into an oven capable of controlling temperature. Increase the temperature by 3 degrees Celsius every 1 minute from room temperature until it reaches 160 to 170 degrees Celsius. Maintain this temperature for 240 minutes. Stop heating to allow the glass to cool down slowly until its temperature drops below 50 degrees Celsius. Then, remove it from the oven and let it cool down further.• Step 6: Remove the glass from the bag from step 5 and laminate it with polycarbonate (3) with a thickness of 3 to 6 millimeters as the final layer. Bond them together using silicone adhesive and let it dry completely.

10. The laminated bulletproof glass as claimed in any one of claims 1 to 9 can be used in vehicles, buildings, counters, bulletproof shields, or any desired areas to resist penetration from bullets or other high-impact object

Images