TWI892829B - Heat-resistant protective mask - Google Patents

Abstract

The present invention relates to a heat-resistant protective mask comprising, in sequence, a polycarbonate molded part, a silicon dioxide hard coat layer, a copper-zinc alloy layer, and a dielectric layer. The dielectric layer comprises titanium nitride, zirconium nitride, zirconium oxide, or a combination thereof. The copper-zinc alloy layer has a thickness of 0.2 μm to 3.0 μm, the dielectric layer has a thickness of 10 nm to 999 nm, and the thickness ratio of the copper-zinc alloy layer to the dielectric layer is 1:1 to 100:1. The heat-resistant protective mask of the present invention has excellent heat resistance, visible light transmittance, and infrared light transmittance, and can reduce costs. After being treated for 200 hours at a temperature of 60°C and a relative humidity of 90%RH, the change rate of infrared light transmittance and visible light transmittance is less than or equal to 100%, which is relatively stable and suitable for long-term use.

Description

Heat-resistant protective mask

The present invention relates to a heat-resistant protective mask, particularly a heat-resistant protective mask suitable for special working environments.

In special working environments, such as welding, grinding, milling, and construction, there may be hazardous factors such as smoke, high heat, and high infrared light. Therefore, operators need to wear protective masks to protect their faces and eyes during the operation to avoid being poisoned by the aforementioned hazardous factors.

To ensure workers' visibility in these special operating environments, protective masks must have a certain light transmittance to ensure visibility while maintaining the required operating capabilities in high-temperature environments. Furthermore, due to the limitations of high-temperature operating environments, if the protective mask lacks sufficient heat resistance, its surface will be easily heated, causing oxidation, melting, and blistering, which will undermine the required protective effect. Furthermore, due to the high infrared light generated in these operating environments, it may also cause eye burns and even retinal burns. Long-term exposure may reduce the elasticity of the lens and lead to vision loss.

Currently available face masks are typically made of a plastic base coated with a pure gold layer. However, due to its high cost, it is not widely available. Therefore, there is an urgent need to develop a low-cost material that can meet the protection requirements and improve the quality of traditional face masks.

In view of the above-mentioned deficiencies of the prior art, one of the objectives of the present invention is to provide a heat-resistant protective mask that can take into account the advantages of low cost, good heat resistance, good infrared light shielding and good visibility.

Another object of the present invention is to improve the stability of the heat-resistant protective mask so that it can maintain good infrared light shielding and good visibility in long-term high-temperature working environments.

To achieve the above object, the present invention provides a heat-resistant protective mask comprising: a polycarbonate molded part; a silicon dioxide hard coating layer located on one surface of the polycarbonate molded part; a copper-zinc alloy layer located on the silicon dioxide hard coating layer, wherein the copper content of the copper-zinc alloy layer is greater than 0% to less than 100%, and the zinc content is less than 100% to greater than 0%; and a dielectric layer located on the copper-zinc alloy layer, comprising titanium nitride (TiN), zirconium nitride (ZrN), zirconium oxide (ZrO ₂ ), or a combination thereof; wherein the thickness of the copper-zinc alloy layer is 0.2 micrometers (μm) to 3.0 μm. μm, the thickness of the dielectric layer is 10 nanometers (nm) to 999 nm, and the thickness ratio of the copper-zinc alloy layer to the dielectric layer is 1:1 to 100:1.

In a specific embodiment of the present invention, the polycarbonate molded part is a lens molded part or a face mask molded part. In this specific embodiment of the present invention, the lens molded part or the face mask molded part can be produced by injection molding, or by first forming a sheet material through extrusion molding, blow molding, casting, or thermoforming, and then processing the sheet material to produce the lens molded part or the face mask molded part. In the present invention, the polycarbonate molded part serves as the substrate.

In a specific embodiment of the present invention, the material of the polycarbonate molded part can be general polycarbonate or commercially available low-retardation polycarbonate.

In a specific embodiment of the present invention, the weight average molecular weight (Mw) of the material of the polycarbonate molded article is 20,000 to 150,000, or 30,000 to 140,000, or 40,000 to 130,000, or 50,000 to 120,000, or 60,000 to 110,000, or 70,000 to 100,000, or 80,000 to 90,000.

In a specific embodiment of the present invention, the polycarbonate molded article has a melt flow index (MI) of 1 g/10min to 30 g/10min, or 5 g/10min to 25 g/10min, or 10 g/10min to 20 g/10min, or 15 g/10min to 20 g/10min, as measured at 190°C and 2.16 kilograms (kg).

In a specific embodiment of the present invention, the glass transition temperature (Tg) of the material of the polycarbonate molded part is 100°C to 180°C, or 110°C to 170°C, or 120°C to 160°C, or 130°C to 150°C, or 130°C to 140°C.

In a specific embodiment of the present invention, the thickness of the polycarbonate molded part is 0.5 millimeters (mm) to 5.0 mm, or 1.0 mm to 4.0 mm, or 1.5 mm to 3.5 mm, or 2.0 mm to 3.0 mm, or 2.0 mm to 2.5 mm.

In a specific embodiment of the present invention, the material of the silica hard coating layer includes silica particles, a hardening polymer and an oligomer. In the present invention, the silica hard coating layer can enhance the surface hardness of the heat-resistant protective mask.

In a specific embodiment of the present invention, the silica hard coating material is applied to one surface of the polycarbonate molded part by spraying or pouring.

In a specific embodiment of the present invention, the hardening polymer in the silica hard coating layer can be a room-temperature hardening polymer, a heat-hardening polymer, and/or an ultraviolet (UV) hardening polymer. In a specific embodiment of the present invention, the hardening polymer in the silica hard coating layer is a room-temperature hardening polymer. After the silica hard coating layer material is applied to a surface of the polycarbonate molded part, the silica hard coating layer is hardened at room temperature to form the silica hard coating layer. In a specific embodiment of the present invention, the hardening polymer in the silica hard coating layer is a heat-hardening polymer. After the silica hard coating layer material is applied to a surface of the polycarbonate molded part, the silica hard coating layer is hardened by heating. In a specific embodiment of the present invention, the curable polymer in the silica hard coating layer is a UV curable polymer. After the silica hard coating material is coated on one surface of the polycarbonate molded part, the silica hard coating layer is cured by UV light to obtain the silica hard coating layer.

In a specific embodiment of the present invention, the solid content of the material of the silica hard coat layer is 1% to 40%, or 5% to 35%, or 10% to 30%, or 15% to 25%, or 20% to 25%.

In specific embodiments of the present invention, the coating thickness (wet film thickness) of the silica hardcoat material is 1 μm to 99 μm, or 10 μm to 90 μm, or 20 μm to 80 μm, or 30 μm to 70 μm, or 40 μm to 60 μm, or 50 μm to 60 μm. In specific embodiments of the present invention, the thickness of the silica hardcoat (after curing) is 1 μm to 30 μm, or 5 μm to 25 μm, or 10 μm to 20 μm, or 15 μm to 20 μm.

In a specific embodiment of the present invention, the copper-zinc alloy layer is deposited on the silicon dioxide hard coat layer. In a specific embodiment of the present invention, the copper-zinc alloy layer is deposited on the silicon dioxide hard coat layer by vacuum sputtering. In the present invention, the copper-zinc alloy layer has thermal conductivity and shielding properties.

In a specific embodiment of the present invention, the copper content of the copper-zinc alloy (Cu/Zn alloy) is greater than or equal to 5% to less than or equal to 95%, and the zinc content is less than or equal to 95% to greater than or equal to 5%; or, the copper content is greater than or equal to 10% to less than or equal to 90%, and the zinc content is less than or equal to 90% to greater than or equal to 10%; or, the copper content is greater than or equal to 15% to less than or equal to 85%, and the zinc content is less than or equal to 85% to greater than or equal to 15%; or, the copper content is greater than or equal to 20% to less than or equal to 80%, and the zinc content is less than or equal to 80% to greater than or equal to 20%; or, the copper content is greater than or equal to 25% to less than or equal to 75%, and the zinc content is less than or equal to 10% 75% to 25% or more; or, the copper content is 30% or more to 70% or less, and the zinc content is 70% or less to 30% or more; or, the copper content is 35% or more to 65% or less, and the zinc content is 65% or less to 35% or more; or, the copper content is 40% or more to 60% or less, and the zinc content is 60% or less to 40% or more; or, the copper content is 45% or more to 55% or less, and the zinc content is 55% or less to 45% or more; or, the copper content is 45% or more to 50% or less, and the zinc content is 50% or less to 45% or more.

In a specific embodiment of the present invention, the thickness of the copper-zinc alloy layer may be 0.5 μm to 2.5 μm, or 1.0 μm to 2.0 μm, or 1.5 μm to 2.0 μm.

In a specific embodiment of the present invention, the dielectric layer is made of titanium nitride, zirconium nitride, or a combination thereof. In the present invention, the dielectric layer has the properties of thermal conductivity and infrared light shielding, and can protect the copper-zinc alloy layer from oxidation.

In a specific embodiment of the present invention, the dielectric layer may be deposited on the copper-zinc alloy layer by a method selected from vacuum sputtering, but is not limited thereto.

In specific embodiments of the present invention, the thickness of the dielectric layer may be 50 nm to 950 nm, or 100 nm to 900 nm, or 150 nm to 850 nm, or 200 nm to 800 nm, or 250 nm to 750 nm, or 300 nm to 700 nm, or 350 nm to 650 nm, or 400 nm to 600 nm, or 450 nm to 550 nm, or 500 nm to 550 nm.

In specific embodiments of the present invention, the thickness ratio of the copper-zinc alloy layer to the dielectric layer can be 5:1 to 95:1, or 10:1 to 90:1, or 15:1 to 85:1, or 20:1 to 80:1, or 25:1 to 75:1, or 30:1 to 70:1, or 35:1 to 65:1, or 40:1 to 60:1, or 45:1 to 55:1, or 50:1 to 55:1. By controlling the thickness of the copper-zinc alloy layer and the dielectric layer, and their thickness ratio, the visibility and thermal conductivity of the heat-resistant face shield can be adjusted.

In a specific embodiment of the present invention, it further comprises a primer layer, which can be formed between the surface of the polycarbonate molded part and the silica hard coating layer to improve the adhesion of the silica hard coating layer to the polycarbonate molded part.

In a specific embodiment of the present invention, the primer layer can be made of polyurethane resin or acrylic resin. In a specific embodiment of the present invention, the primer layer can be solvent-based or water-based. In a specific embodiment of the present invention, the primer layer was purchased from Changxing Materials and its main components are SO-GEL inorganic sol and acrylic resin.

In a specific embodiment of the present invention, the glass transition temperature (Tg) of the material of the primer layer is 70°C to 120°C, or 80°C to 110°C, or 90°C to 100°C.

In a specific embodiment of the present invention, the solid content of the material of the primer layer is 0% to 100%, or 10% to 90%, or 20% to 80%, or 30% to 70%, or 40% to 60%, or 50% to 60%.

In a specific embodiment of the present invention, the heat-resistant protective mask has good heat resistance, and its melting temperature is above 150°C, or above 160°C, or above 170°C, or above 180°C, or above 190°C, or above 200°C, or above 210°C, or above 220°C, or above 230°C.

In this invention, parameters such as infrared light transmittance and visible light transmittance are subjected to tolerance testing, which includes treating the device at a temperature of 60°C and a relative humidity of 90% for 200 hours. The infrared light transmittance and visible light transmittance before and after the test are measured, and their stability is calculated.

In specific embodiments of the present invention, the infrared light transmittance of the heat-resistant protective mask is 0.6% to 20%, or 0.6% to 18%, or 0.6% to 15%, or 0.6% to 10%, or 0.6% to 5%, or 0.6% to 2.5% (complying with EN 169 and/or EN 171 safety standards). In the present invention, infrared light refers to light with a wavelength of 760 nm to 1 mm, light with a wavelength of 780 nm to 2000 nm, or light with a wavelength of 780 nm to 1400 nm. If the infrared light transmittance of the heat-resistant protective mask of the present invention is too high, it indicates poor infrared light shielding effectiveness and cannot effectively protect the operator's face or eyes from the harmful effects of high infrared light.

In a specific embodiment of the present invention, after the heat-resistant protective mask is treated at a temperature of 60°C and a relative humidity of 90% for 200 hours, the change rate of infrared light transmittance is less than 100%, less than 750%, less than 50%, less than 45%, less than 40%, less than 30%, less than 20%, less than 15%, or less than 10%.

In specific embodiments of the present invention, the visible light transmittance of the heat-resistant face shield is 2.5% to 50%, or 2.5% to 40%, or 2.5% to 30%, or 2.5% to 20%, or 2.5% to 10%, or 2.5% to 7%, or 2.5% to 6%, or 2.5% to 5% (complying with EN 169 and/or EN 171 safety standards). If the visible light transmittance of the heat-resistant face shield of the present invention is too low, it cannot be used as a face shield or goggles; however, if the visible light transmittance of the heat-resistant face shield of the present invention is too high, the protective effect may not be achieved.

In a specific embodiment of the present invention, after the heat-resistant protective mask is treated at a temperature of 60°C and a relative humidity of 90% for 200 hours, the change rate of visible light transmittance is less than 100%, or less than 70%, or less than 40%, or less than 30%, or less than 20%, or less than 10%.

In a specific embodiment of the present invention, the aforementioned resistance test may further include a step of irradiating with a 500-watt (W) UV light for 200 hours.

In a specific embodiment of the present invention, the polycarbonate molded part is a lens molded part or a mask molded part.

The heat-resistant protective mask of the present invention comprises a copper-zinc alloy layer and a dielectric layer. The copper-zinc alloy layer significantly reduces manufacturing costs, while the dielectric layer protects the copper-zinc alloy layer from oxidation. Furthermore, the heat-resistant protective mask as a whole exhibits excellent heat resistance (melting temperature above 150°C), infrared light transmittance (0.6% to 20%), and visible light transmittance (2.5% to 50%), making it suitable as a protective mask. Furthermore, the heat-resistant face shield can withstand operating temperatures ranging from 40°C to 250°C. After 200 hours of exposure to temperatures of 60°C and a relative humidity of 90% RH, its infrared and visible light transmittances exhibited low variability, both below 100%, demonstrating relative stability. This ensures excellent infrared shielding and visibility even in prolonged high-temperature operating environments.

The objectives, advantages and technical features of the present invention will become apparent through the following detailed description of the embodiments and the accompanying drawings.

As shown in FIG1 , the heat-resistant protective mask 1 of the present invention comprises: a polycarbonate molded part 11 , a silicon dioxide hard coating layer 12 , a copper-zinc alloy layer 13 , and a dielectric layer 14 .

Preparation of the heat-resistant protective mask of the present invention

First, a polycarbonate molded part is provided, forming a transparent face shield that can cover a person's face. A silica hardcoat material (comprising silica microparticles, a curing polymer, and an oligomer) is then applied to one surface of the polycarbonate molded part. After curing, a silica hardcoat layer with a thickness of 4±1 μm is formed.

A copper-zinc alloy layer was sputter-plated on the silicon dioxide hard coat layer using a vacuum sputter plating method according to the copper-zinc alloy layer materials shown in Tables 1 and 2. Examples 1-6 (E1-E6) and Comparative Examples 1-5 (C1-C5) were sputter-plated with copper-zinc alloys, with the atomic percent (at%) of copper and zinc and the thickness of the copper-zinc alloy layer shown in Tables 1 and 2. Comparative Examples 6 and 7 were sputter-plated with conventional gold (pure gold). Comparative Example 5 did not include a copper-zinc alloy layer.

A dielectric layer was then sputter-coated on the copper-zinc alloy layer of Examples 1-6 (E1-E6) using the dielectric layer materials shown in Tables 1 and 2. Comparative Examples 1-7 (C1-C7) were not sputter-coated with a dielectric layer. Thus, heat-resistant protective masks for each of the Examples and Comparative Examples were produced.

Endurance test

The heat-resistant protective masks of the aforementioned embodiments and comparative examples were subjected to tolerance tests to evaluate changes in visible light transmittance and infrared light transmittance of the protective masks before and after exposure to a long-term high-temperature environment. The aforementioned endurance test was conducted according to the ISO4892-2 standard method, but with more stringent parameters: first, exposure to a UV lamp (lamp brand: USHIO, model: UXL-450SP, a 500W xenon lamp) for 200 hours at an illumination of 13,000 lumens (lm); then, treatment for 200 hours in an incubator (equipment brand: Jufu, model: GTH-408-SSP-SD) at a high temperature of 60°C and a relative humidity of 90% RH. Heat resistance tests were performed on samples of each embodiment and comparative example before the endurance test. Infrared light transmittance and visible light transmittance tests were performed on samples of each embodiment and comparative example before and after the endurance test, respectively. The changes in infrared light transmittance and visible light transmittance were calculated.

Heat resistance test

Before endurance testing, samples from each Example and Comparative Example were placed in an oven and the temperature was gradually increased to 230°C. Visual observation was performed, and the temperature at which each sample began to foam and melt was recorded. If the sample had not melted at 230°C, it was recorded as above 230°C (i.e., >230°C). The results are shown in Tables 1 and 2.

Visible light transmittance test

A spectrometer (brand: HITACHI, model: UH-4150, with built-in Sunglasses Certification software) was used to measure the visible light transmittance (%) of each Example and Comparative Example before and after the endurance test. The change in visible light transmittance was calculated using the following formula. The results are shown in Tables 1 and 2. Change rate of visible light transmittance = (Visible light transmittance after test – Visible light transmittance before test) x100% Visible light transmittance before test

Infrared light transmittance test

A spectrometer (brand: HITACHI, model: UH-4150, with built-in Sunglasses Certification software) was used to measure the infrared transmittance (%) of each Example and Comparative Example before and after the withstand test. The change in infrared transmittance was calculated using the following formula. The results are shown in Tables 1 and 2. Change rate of infrared light transmittance = (Infrared light transmittance after test – Infrared light transmittance before test) x100% Infrared transmittance before test

Table 1. Materials of Examples 1-6 (E1 to E6) and their heat resistance, visible light transmittance, and infrared light transmittance data E1 E2 E3 E4 E5 E6 Copper-zinc alloy layer Alloy materials Cu Zn Cu Zn Cu Zn Cu Zn Cu Zn Cu Zn Alloy ratio (at%) 85 15 85 15 70 30 60 40 85 15 85 15 Thickness (μm) 70±10% 70±10% 70±10% 70±10% 40±10% 70±10% dielectric layer Material TiN TiN TiN TiN TiN Zn Thickness (nm) 20 30 20 20 20 35 Heat resistance Melting temperature (°C) >230 >230 About 185 About 168 About 220 210 to 220 Visible light transmittance Before tolerance test 4.30% 3.3% 2.1% 1.8% 41.1% 1.4% After tolerance test 5.8% 3.7% 3.1% 2.9% 44.2% 2.8% Rate of change 34.88% 12.12% 47.62% 61.11% 7.54% 100.00% Infrared light transmittance Before tolerance test 0.46% 0.86% 1.3% 2.6% 16.9% 0.64% After tolerance test 0.65% 0.95% 1.8% 3.1% 17.8% 0.88% Rate of change 41.30% 10.47% 38.46% 19.23% 5.33% 37.50%

Table 2, Materials of Comparative Examples 1-7 (C1 to C7) and Their Heat Resistance, Visible Light Transmittance, and Infrared Light Transmittance Data C1 C2 C3 C4 C5 C6 C7 Copper-zinc alloy layer Alloy materials Cu Zn Cu Zn Cu Zn Cu Zn without Au Au Alloy ratio (at%) 85 15 85 15 70 30 60 40 Thickness (μm) 70±10% 40±10% 70±10% 70±10% without 150±10% 120±10% dielectric layer Material without without without without without without without Thickness (nm) without without without without without without without Heat resistance Melting temperature (°C) >230 About 220 About 190 About 180 About 140 >230 >230 Visible light transmittance Before tolerance test 1.2% 48% 3.2% 3.9% 5% 4.3% 48.2% After tolerance test 7.6% 66% 10.7% 11.8% 5% 5.7% 52% Rate of change 533.33% 37.50% 234.38% 202.56% 0.00% 32.56% 7.88% Infrared light transmittance Before tolerance test 0.18% 18.1% 1.6% 2.7% 75% 0.4% 16.3% After tolerance test 6.5% 48.1% 11.2% 12.1% 75% 0.48% 17% Rate of change 3511.11% 165.75% 600.00% 348.15% 0.00% 20.00% 4.29%

As can be seen from Tables 1 and 2, in Comparative Examples 1-4 (C1-C4), although copper-zinc alloy is used as the copper-zinc alloy layer, due to the lack of protection of the dielectric layer, the infrared light transmittance and visible light transmittance after the tolerance test are relatively high, such as Comparative Example 2 (C2). In other words, the proportion of visible light and infrared light that can penetrate the heat-resistant protective mask is relatively high; In addition, even if the infrared light transmittance and visible light transmittance after the tolerance test are still within the safe range, the change rate of the infrared light transmittance and visible light transmittance before and after the tolerance test of some comparative examples is also relatively high, such as Comparative Examples 1, 3, and 4. The results of the following experiments (C1, C3, and C4) indicate that these heat-resistant face shields exhibit poor stability and lose their infrared light shielding effectiveness after prolonged use in high-temperature environments. Furthermore, Example 5 (C5), which lacks both a copper-zinc alloy layer and a dielectric layer, exhibits significant heat resistance, blistering and melting at 140°C. Using gold, a conventional material, for the copper-zinc alloy layer achieves comparable performance even without a dielectric layer, but at a significantly higher cost.

In addition, the oxidation of the copper-zinc alloy layer was observed for the heat-resistant protective masks of Examples 1 and 2 (E1, E2) and Comparative Example 1 (C1).

Infrared light transmission spectra of Examples 1 and 2 (E1 and E2) and Comparative Example 1 (C1) are shown in Figures 2A-2C, respectively. Furthermore, photographs of the heat-resistant face shields of Comparative Example 1 (C1) and Examples 1 and 2 (E1 and E2) after endurance testing are shown in Figures 3A-3C. The above testing and observation results show that the pure copper copper-zinc alloy layer in Comparative Example 1 (C1), which lacks a dielectric layer, exhibits significant oxidation. However, this is not the case with Examples 1 and 2 (E1 and E2), which have dielectric layers, and therefore meet 3M specifications.

As can be seen from the above, the heat-resistant protective mask of the present invention replaces the conventional pure gold plating with a copper-zinc alloy layer and a dielectric layer, which can reduce manufacturing costs. Moreover, the heat-resistant protective mask as a whole has good heat resistance, visible light transmittance, and infrared light transmittance, making it suitable as a human protective gear. Furthermore, the dielectric layer in the heat-resistant protective mask not only assists in heat conduction and shields infrared light, but also protects the copper-zinc alloy layer from oxidation. The heat-resistant protective mask can be used at operating temperatures between 40°C and 250°C, and the variability in infrared and visible light transmittance before and after treatment for 200 hours at a temperature of 60°C and a relative humidity of 90% RH is low and relatively stable. Therefore, the heat-resistant protective mask of the present invention is suitable for long-term use.

1: Heat-resistant protective visor 11: Polycarbonate molding 12: Silicon dioxide hard coat 13: Copper-zinc alloy layer 14: Dielectric layer

Figure 1 is a schematic side view of the heat-resistant protective mask of the present invention. Figure 2A is a graph showing the infrared light transmission spectrum of the heat-resistant protective mask of Example 1 (E1) after a heat-resistant test. Figure 2B is a graph showing the infrared light transmission spectrum of the heat-resistant protective mask of Example 2 (E2) after a heat-resistant test. Figure 2C is a graph showing the infrared light transmission spectrum of the heat-resistant protective mask of Comparative Example 1 (C1) after a heat-resistant test. Figure 3A is a photograph of the heat-resistant protective mask of Comparative Example 1 (C1) after a heat-resistant test. Figure 3B is a photograph of the heat-resistant protective mask of Example 1 (E1) after a heat-resistant test. Figure 3C is a photograph of the heat-resistant protective mask of Example 2 (E2) after a heat-resistant test.

1: Heat-resistant protective mask

11: Polycarbonate moldings

12: Silicon dioxide hard coating

13: Copper-zinc alloy layer

14: Dielectric layer

Claims (12)

A heat-resistant protective mask comprises: a polycarbonate molded part; a silicon dioxide hard coating layer located on one surface of the polycarbonate molded part; a copper-zinc alloy layer located on the silicon dioxide hard coating layer, wherein the copper content of the copper-zinc alloy layer is greater than 0% and less than 100%, and the zinc content is less than 100% and greater than 0%; and a dielectric layer located on the copper-zinc alloy layer, comprising titanium nitride, zirconium nitride, zirconium oxide, or a combination thereof; wherein the copper-zinc alloy layer has a thickness of 0.2 μm to 3.0 μm, the dielectric layer has a thickness of 10 nm to 999 nm, and the thickness ratio of the copper-zinc alloy layer to the dielectric layer is 1:1 to 100:1. The heat-resistant protective mask as described in claim 1, wherein the copper content in the copper-zinc alloy layer is greater than or equal to 30% and less than or equal to 70%, and the zinc content is less than or equal to 70% and greater than or equal to 30%. A heat-resistant protective mask as described in claim 1, wherein the melting temperature of the heat-resistant protective mask is above 150°C. The heat-resistant protective mask as described in claim 1, wherein the copper content in the copper-zinc alloy layer is greater than or equal to 5% and less than or equal to 95%, and the zinc content is less than or equal to 95% and greater than or equal to 5%. The heat-resistant protective mask as described in claim 1, wherein the thickness ratio of the copper-zinc alloy layer to the dielectric layer is 1:5 to 1:95. The heat-resistant protective mask as described in claim 1 further comprises a primer layer, which is located between the surface of the polycarbonate molded part and the silica hard coating layer. The heat-resistant protective mask as described in claim 6, wherein the material of the primer layer is polyurethane resin or acrylic resin. A heat-resistant protective mask as described in claim 1 or 6, wherein the heat-resistant protective mask has a visible light transmittance of 2.5% to 50%. A heat-resistant protective mask as described in claim 1 or 6, wherein the change rate of visible light transmittance of the heat-resistant protective mask after being treated at a temperature of 60°C and a relative humidity of 90% for 200 hours is less than or equal to 100%. A heat-resistant protective mask as described in claim 1 or 6, wherein the infrared light transmittance of the heat-resistant protective mask is 0.6% to 20%. A heat-resistant protective mask as described in claim 1 or 6, wherein the change rate of infrared light transmittance of the heat-resistant protective mask after being treated at a temperature of 60°C and a relative humidity of 90% for 200 hours is less than or equal to 100%. A heat-resistant protective mask as described in claim 1 or 6, wherein the polycarbonate molded part is a lens molded part or a mask molded part.