A self-regulating heating cloth with low electromagnetic radiation

Abstract

This application relates to the field of electrothermal materials, and in particular to a self-regulating heating cloth with low electromagnetic radiation. The self-regulating heating cloth with low electromagnetic radiation includes an insulating silicone protective layer and a base fabric. The base fabric is woven with several self-regulating heating wires, several first conductive strips, and two second conductive strips. The first and second conductive strips are both conductive composite yarns, which are composed of several conductive composite yarns, including S-twist conductive composite yarns and Z-twist conductive composite yarns, which are spaced apart to form the conductive composite yarn. The self-regulating heating cloth of this application has low electromagnetic radiation intensity and better safety performance.

Description

Technical Field

[0001] This application relates to the field of electrothermal materials, and in particular to a self-regulating heating cloth with low electromagnetic radiation. Background Technology

[0002] The self-regulating heating cloth has a heating function, and its resistance decreases as the temperature rises. When the threshold is reached, the resistance rises sharply, causing the heating power to drop sharply, thus avoiding unnecessary safety accidents caused by excessive temperature. This gives the self-regulating heating cloth excellent safety performance.

[0003] An existing self-regulating heating fabric, such as the mattress disclosed in announcement number CN220423583U, includes a self-regulating heating fabric comprising a warp and weft woven fabric and an insulating silicone protective layer. The warp and weft woven fabric is located inside the insulating silicone protective layer. A plurality of self-regulating heating lines are woven into the warp and weft woven fabric. The self-regulating heating lines are parallel to the weft threads in the warp and weft woven fabric. A plurality of first conductive strips are woven into the warp and weft woven fabric, and the first conductive strips are in contact with the self-regulating heating lines. The first conductive strips are parallel to the warp threads in the warp and weft woven fabric. Two second conductive strips are woven into the warp and weft woven fabric, and the second conductive strips are located at opposite ends near the weft threads of the warp and weft woven fabric. The self-regulating heating lines, the first conductive strips, and the second conductive strips are connected to a power source to form a current return flow, causing the self-regulating heating lines to release heat.

[0004] In actual production, both the first and second conductive strips are composed of multiple nickel-plated copper wire bundles. The multiple nickel-plated copper wire bundles in the first conductive strip are woven as warp threads into the warp-weft woven fabric. The multiple nickel-plated copper wire bundles in the second conductive strip are woven as weft threads into the warp-weft woven fabric. Because both the first and second conductive strips generate magnetic and electric fields when energized, excessively strong electric and magnetic fields can cause electromagnetic hazards, affecting the safety performance of the self-regulating heating fabric. To further optimize the safety performance of the self-regulating heating fabric, the inventors have provided a self-regulating heating fabric with low electromagnetic radiation. Utility Model Content

[0005] To address the electromagnetic hazard issues associated with the first and second conductive strips in existing self-regulating heating fabrics, the inventors further optimized the structure of the first and second conductive strips, providing a self-regulating heating fabric with low electromagnetic radiation.

[0006] The low electromagnetic radiation self-regulating heating cloth provided in this application is achieved through the following technical solution: A low-electromagnetic-radiation self-regulating heating fabric includes an insulating silicone protective layer and a base fabric located inside the insulating silicone protective layer. The base fabric is woven with a plurality of self-regulating heating threads parallel to the weft threads. The base fabric also includes a plurality of first conductive strips that are in contact with the self-regulating heating threads and parallel to the warp threads. Two second conductive strips are woven into the base fabric, parallel to the weft threads, and are located at opposite ends near the weft threads. Both the first and second conductive strips are conductive composite yarns, each composed of a plurality of conductive composite yarns. These conductive composite yarns include S-twist conductive composite yarns and Z-twist conductive composite yarns, which are spaced apart to form the conductive composite yarn.

[0007] The magnetic field generated by the S-twist conductive composite yarn is opposite in direction to that generated by the Z-twist conductive composite yarn. The opposing magnetic fields cancel each other out, which significantly reduces the electromagnetic radiation intensity generated by the first and second conductive strips. This results in a relatively lower electromagnetic radiation intensity for the self-regulating heating fabric, improving its safety performance and enhancing the core competitiveness of the self-regulating heating fabric series.

[0008] Preferably, the S-twist conductive composite yarn is made by winding and twisting a single nickel-plated copper foil, with the twist being S-twist and a twist degree of 2000 TPM.

[0009] Preferably, the Z-twist conductive composite yarn is made by winding and twisting a single nickel-plated copper foil, with the twist being Z-twist and a twist degree of 2000 TPM.

[0010] By adopting the above technical solution, the electromagnetic radiation intensity of the self-regulating heating cloth can be effectively reduced.

[0011] Preferably, the S-twist conductive composite yarn includes an elastic yarn A as the core yarn and a plurality of conductive filaments A wound clockwise spirally around the elastic yarn A.

[0012] Preferably, the Z-twist conductive composite yarn includes an elastic yarn B as the core yarn and a plurality of conductive filaments B wound counterclockwise spirally around the elastic yarn B.

[0013] Preferably, the elastic yarn A and the elastic yarn B are 250D polyester or nylon.

[0014] Preferably, the conductive wire A and the conductive wire B are nickel-plated copper foils; the nickel-plated copper foils have a width of 0.33 mm and a thickness of 0.03 mm.

[0015] By adopting the above technical solution, not only can the electromagnetic radiation intensity of the self-regulating heating fabric be effectively reduced, but its smoothness and wrinkle resistance can also be improved. Specifically, the smoothness problem of the self-regulating heating fabric lies in the difference between the volume expansion coefficient of the metal conductive filaments and the volume expansion coefficients of the warp and weft yarns in the base fabric. When the copper-nickel alloy filaments are woven, they are subjected to warp tension and elongation. After the tension is released from the machine, the copper-nickel alloy filaments spring back and undergo irreversible tensile deformation. After weaving, they are restricted by the warp and weft yarns and cannot fully recover, resulting in wrinkles. The copper-nickel alloy filaments are made by twisting multiple strands of monofilament metal wires together. They are shaped during the winding process, but loosening during weaving causes the twisted metal wires to spring back. The phenomenon is that after the tension is removed, the twisting direction of adjacent metal wires is inconsistent, causing wrinkles on the fabric surface. When the copper-nickel alloy filaments are used as the warp yarns in the heating fabric weaving process, they bear a certain amount of stress. When the copper-nickel alloy filaments are stretched under tension, and the warp tension is removed after the fabric is woven off the loom, the copper-nickel alloy filaments exhibit partial shrinkage upon rebound. Specifically, this manifests as wavy wrinkles on the fabric surface at the position of the copper-nickel alloy filaments after the heated fabric is removed from the loom, affecting the smoothness of the self-regulating heated fabric. However, S-twist conductive composite yarns and Z-twist conductive composite yarns, which are prepared using elastic yarn as the core yarn, have better compatibility with the volume expansion coefficients of the warp and weft yarns in the base fabric. The twisted conductive composite yarns (i.e., S-twist conductive composite yarns and Z-twist conductive composite yarns) experience thermal expansion and contraction, causing the copper foil to shrink and expand. Both are warp-oriented spirals, similar to a spring effect, reducing the stretching and rebound effect, decreasing wrinkles, and thus improving the overall smoothness and wrinkle resistance.

[0016] Preferably, the S-twist conductive composite yarn includes a conductive elastic yarn A as the core yarn and a conductive filament C wound clockwise spirally around the conductive elastic yarn A.

[0017] Preferably, the Z-twist conductive composite yarn includes a conductive elastic yarn B as the core and a conductive filament D wound counterclockwise spirally around the conductive elastic yarn B.

[0018] Preferably, the conductive elastic yarn A and the conductive elastic yarn B are DDY composite conductive filaments, and the specifications of the DDY composite conductive filaments are 30D / 4f or 60D / 8f; the conductive wire C and the conductive wire D are nickel-plated copper foils; the width of the nickel-plated copper foils is 0.33mm and the thickness is 0.03mm.

[0019] This not only effectively reduces the electromagnetic radiation intensity of self-regulating heating fabrics, but also improves their smoothness and wrinkle resistance. Furthermore, S-twist and Z-twist conductive composite yarns prepared using DDY composite conductive filaments as the core yarn exhibit superior conductivity and lower electrical loss, thus improving heating efficiency.

[0020] In summary, this application has the following advantages: 1. The self-regulating heating cloth provided in this application has relatively lower electromagnetic radiation and better safety performance, thereby enhancing the core competitiveness of the self-regulating heating cloth series products.

[0021] 2. Regarding the flatness and wrinkle resistance of the self-regulating heating fabric provided in this application, the original conductive wire is a copper-nickel alloy filament, which undergoes significant thermal expansion and contraction after heating. The degree of contraction is inconsistent with that of the warp and weft yarns, resulting in wavy wrinkles on the conductive strip after the woven fabric is unloaded, which is detrimental to the flatness of the product and subsequent processing. In contrast, the copper foil-coated conductive wire in this application is a ring-shaped coating, and its own spring-like spiral structure offsets the degree of thermal expansion and contraction. After the woven fabric is unloaded, the conductive strip is flat without wavy wrinkles, and the finished self-regulating heating fabric is flatter. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the low electromagnetic radiation self-limiting heating cloth in Example 1.

[0023] Figure 2 This is a schematic diagram of the base fabric of the low electromagnetic radiation self-limiting temperature heating cloth in Example 1.

[0024] Figure 3 This is a schematic diagram of the connection structure between the first conductive strip of the base fabric and the self-limiting heating wire in Example 1.

[0025] Figure 4 This is a schematic diagram of the structure of the S-twist conductive composite yarn and the Z-twist conductive composite yarn in Example 2.

[0026] Figure 5 This is a schematic diagram of the structure of the S-twist conductive composite yarn and the Z-twist conductive composite yarn in Example 2.

[0027] In the diagram, 1. Insulating silicone protective layer; 2. Base fabric; 20. Self-regulating heating wire; 3. First conductive strip; 4. Second conductive strip; 41. Second conductive strip A; 42. Second conductive strip B; 421. Second conductive strip B1; 422. Second conductive strip B2; 5. Conductive composite yarn; 50. Conductive composite yarn; 51. S-twist conductive composite yarn; 511. Elastic yarn A; 512. Conductive filament A; 513. Conductive elastic yarn A; 514. Conductive filament C; 52. Z-twist conductive composite yarn; 521. Elastic yarn B; 522. Conductive filament B; 523. Conductive elastic yarn B; 524. Conductive filament D; 6. Wire connection port; 7. Power adapter; 71. Power connection wire A; 72. Power connection wire B. Detailed Implementation

[0028] The technical solution of this application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0029] Example 1: Refer to Figure 1A self-regulating heating cloth with low electromagnetic radiation includes an insulating silicone protective layer 1 and a base cloth 2 located inside the insulating silicone protective layer 1. The base cloth 2 is woven with a number of self-regulating heating threads 20 that are parallel to the weft threads in the base cloth 2.

[0030] The resistance of the self-regulating heating wire 20 was measured to be 4.0*10 at 10℃. 2 -2.0*10 3 Ω*m.

[0031] Preferably, the resistance of the self-limiting heating wire 20 is measured to be 4.0*10 at 10°C. 2 -8*10 2 Ω*m, meaning the heating voltage of the self-regulating heating cloth 4 is controlled between 12-36V, giving this application good performance and safety. Specifically, the self-regulating heating wire 32 is the self-regulating heating wire developed by the applicant, Zhejiang Danting New Materials Co., Ltd., an electric heating wire with intelligent temperature control function in application number 2023104652588, and the self-regulating heating wire in embodiment 33 of the heating module assembly prepared using it. The wire resistance was measured to be 418.4Ω*m at 10℃.

[0032] The self-regulating heating wire 20 is composed of a T300 1K carbon fiber core and a self-regulating heating outer layer composited around the T300 1K carbon fiber core. The self-regulating heating outer layer is prepared from the following raw materials in the indicated weight percentages: 795g PP resin, 420g HDPE resin, 185g EVA resin, 292g carbon black, 8g titanium diboride, 160g nano zinc oxide, 18g antioxidant 1024, 10g antioxidant 697, 3.0g antioxidant DBHQ, 2.2g nano zirconium carbide, 2.9g nano titanium carbide, 0.29g nano titanium nitride, 0.58g nano silicon nitride, 2.9g UV-234, 1.16g UV-622, 0.87g UV-770, and 4g zinc stearate. The preparation method of the self-regulating heating wire includes the following steps: S1, PP resin, HDPE resin, and EVA resin are dried until the moisture content is below 0.1% and set aside for later use; 795g of dried PP resin, 420g of HDPE resin, 185g of EVA resin, 292g of carbon black, 8g of titanium diboride, 160g of nano zinc oxide, 18g of antioxidant 1024, 10g of antioxidant 697, 3.0g of antioxidant DBHQ, 2.2g of nano zirconium carbide, 2.9g of nano titanium carbide, 0.29g of nano titanium nitride, 0.58g of nano silicon nitride, 2.9g of UV-234, 1.16g of UV-622, 0.87g of UV-770, and 4g of zinc stearate were placed in a mixer and mixed evenly. The mixture was then subjected to internal mixing at 166℃ for 300 seconds. S2, the intensively mixed material obtained in S1 is placed in a twin-screw extruder for melt extrusion. The extrusion temperature is 175-195℃, specifically divided into five heating temperature zones: zone 1 170℃±0.5℃, zone 2 180℃±0.5℃, zone 3 190℃±0.5℃, zone 4 195℃±0.5℃, and zone 5 195℃±0.5℃. The screw speed is 38 r / min, and the die temperature is 193.6℃. After drawing, water cooling, and granulation, an electrothermal material with intelligent temperature control function with a thickness of 1.0-1.2 mm is obtained and dried until the moisture content is below 0.1%. S3 uses Toray T300 1K carbon fiber. The spinning masterbatch is placed in a twin-screw extruder, and the extrusion temperature is 175-195℃, specifically divided into five heating temperature zones: Zone 1 170℃±0.5℃, Zone 2 180℃±0.5℃, Zone 3 190℃±0.5℃, Zone 4 195℃±0.5℃, and Zone 5 195℃±0.5℃. The screw speed is 38 r / min, and the die temperature is 192.8℃. The resulting extruded molten material adheres to the outer surface of the core wire. The traction speed is 10.0 cm / s. Water cooling and heat treatment: After water cooling, the semi-finished yarn is placed in a 60℃ oven for 3.6m, then in an 80℃ oven for 5.4m, then in a 60℃ oven for 3.6m, and finally air-cooled at room temperature for 5.4m to obtain an 800D finished self-regulating heated yarn.

[0033] Reference Figure 1 and Figure 2 The base fabric 2 is woven with several first conductive strips 3 that are in contact with the self-regulating heating wire 20 and are parallel to the warp threads of the base fabric 2. The base fabric 2 is also woven with two second conductive strips 4 that are parallel to the weft threads of the base fabric 2, and the two second conductive strips 4 are located at opposite ends near the weft threads of the base fabric 2. The self-regulating heating wire 20, the first conductive strips 3, and the second conductive strips 4 are connected to a power source to form a current return flow, causing the self-regulating heating wire 20 to generate heat through the thermal effect of the current, thus achieving an electric heating effect.

[0034] Reference Figure 1 and Figure 2 Two second conductive strips 4 are designated as second conductive strip A41 and second conductive strip B42. Several first conductive strips 3 are labeled 1, 2, 3..., where n is an even number. Among the several first conductive strips 3, the first conductive strip 3 labeled 1 has one end connected to the second conductive strip A41 and its other end connected to the second conductive strip B42, and the first conductive strip 3 labeled 1 is in contact with the self-regulating heating wire 20.

[0035] Reference Figure 2One end of the even-numbered first conductive strip 3 is connected to the second conductive strip B42, and the other end is not connected to the second conductive strip A41. That is, the even-numbered first conductive strip 3 has a break A. The vertical projection of the break A is located in the area between the second conductive strip A41 and the self-limiting heating line 20 adjacent to the second conductive strip A41. However, the even-numbered first conductive strip 3 is in contact with the self-limiting heating line 20.

[0036] Reference Figure 2 Among the several first conductive strips 3, the odd-numbered first conductive strips 3 (excluding the one labeled 1) are connected at one end to the second conductive strip A41, and at the other end are not connected to the second conductive strip B42. That is, the odd-numbered first conductive strips 3 (excluding the one labeled 1) have a break B. The vertical projection of the break B is located in the area between the second conductive strip B42 and the self-limiting heating line 20 adjacent to the second conductive strip B42. However, the odd-numbered first conductive strips 3 (excluding the one labeled 1) are all in contact with the self-limiting heating line 20.

[0037] Reference Figure 2 The second conductive strip B42 is cut to form the wire connection port 6, dividing the second conductive strip B42 into a second conductive strip B1421 and a second conductive strip B2422, such that the second conductive strip B1421 is not connected to the second conductive strip B2422. The second conductive strip B1421 is in contact with the first conductive strip 3 numbered 1 among the plurality of first conductive strips 3. The second conductive strip B2422 is in contact with the first conductive strips 3 numbered 2, 3...n among the plurality of first conductive strips 3, but not with the first conductive strip 3 numbered 1 among the plurality of first conductive strips 3. A power connection wire A71 is soldered to one end of the second conductive strip B1421 at the wire connection port 6, and a power connection wire B72 is soldered to one end of the second conductive strip B2422 at the wire connection port 6. Both power connection wires A and B are connected to the power adapter 7, which has an input of 100-300VAC and an output of 12-36VDC.

[0038] Reference Figure 2 and Figure 3 The first conductive strip 3 and the second conductive strip 4 are both conductive composite yarn strips 5, which are composed of several conductive composite yarns 50. The conductive composite yarns 50 include S-twist conductive composite yarns 51 and Z-twist conductive composite yarns 52, which are spaced apart to form the conductive composite yarns 50. The magnetic field generated by the S-twist conductive composite yarn 51 is opposite in direction to that generated by the Z-twist conductive composite yarn 52. These opposite magnetic fields cancel each other out, significantly reducing the electromagnetic radiation intensity generated by the first conductive strip 3 and the second conductive strip 4. This results in a relatively lower electromagnetic radiation intensity for the self-regulating heating fabric, improving its safety performance and enhancing the core competitiveness of the self-regulating heating fabric series products.

[0039] Reference Figure 2 and Figure 3 S-twist conductive composite yarn 51 is made by winding and twisting a single strand of nickel-plated copper foil, with an S-twist and a twist of 2000 TPM. Z-twist conductive composite yarn 52 is made by winding and twisting a single strand of nickel-plated copper foil, with a Z-twist and a twist of 2000 TPM. The width of the nickel-plated copper foil is 0.33 mm and the thickness is 0.03 mm.

[0040] Reference Figure 2 and Figure 3 Specifically, the conductive composite yarn tape 5 contains 4 S-twist conductive composite yarns 51 and 3 Z-twist conductive composite yarns 52. The specific arrangement of the conductive composite yarn tape 5 is: S-twist conductive composite yarn 51 / Z-twist conductive composite yarn 52 / S-twist conductive composite yarn 51 / Z-twist conductive composite yarn 52 / S-twist conductive composite yarn 51 / Z-twist conductive composite yarn 52 / S-twist conductive composite yarn 51.

[0041] The spacing between adjacent self-regulating heating wires 20 is 8 cm, and the spacing between adjacent first conductive strips 3 is 32 cm. There are 6 first conductive strips 3 and 18 self-regulating heating wires 20. The magnetic field strength B and electric field strength E near the 6 first conductive strips 3 were measured, and the average value ∑B was taken. ∑B is 0 μT, and ∑E is 12.6 V / m. In contrast, the self-regulating heating cloth disclosed in CN220423583U has ∑B of 0.72 μT and ∑E of 28.0 V / m. Therefore, it can be seen that the self-regulating heating cloth has relatively lower electromagnetic radiation, better safety performance, and enhances the core competitiveness of the self-regulating heating cloth series products.

[0042] The difference between Example 2 and Example 1 is that: (Refer to...) Figure 4 The S-twist conductive composite yarn 51 includes an elastic yarn A511 as the core and a conductive filament A512 wound clockwise spirally around the elastic yarn A511. The Z-twist conductive composite yarn 52 includes an elastic yarn B521 as the core and a conductive filament B522 wound counterclockwise spirally around the elastic yarn B521. The elastic yarns A511 and B521 are 250D polyester or 250D nylon yarns. The conductive filaments A512 and B522 are nickel-plated copper foil, with a width of 0.33mm and a thickness of 0.03mm.

[0043] The difference between Example 3 and Example 1 is that: (Refer to...) Figure 5The S-twist conductive composite yarn 51 includes a conductive elastic yarn A513 as the core and a conductive filament C514 wound clockwise spirally around the conductive elastic yarn A513. The Z-twist conductive composite yarn 52 includes a conductive elastic yarn B523 as the core and a conductive filament D524 wound counterclockwise spirally around the conductive elastic yarn B523. The conductive elastic yarns A513 and B523 are DDY composite conductive filaments with a specification of 30D / 4f or 60D / 8f. The conductive filaments C514 and D524 are nickel-plated copper foil with a width of 0.33mm and a thickness of 0.03mm.

[0044] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A self-regulating heating cloth with low electromagnetic radiation, comprising an insulating silicone protective layer (1) and a base cloth (2) located inside the insulating silicone protective layer (1), wherein the base cloth (2) is woven with a plurality of self-regulating heating threads (20) parallel to the weft threads in the base cloth (2); wherein the base cloth (2) is woven with a plurality of first conductive strips (3) that are in contact with the self-regulating heating threads (20) and parallel to the warp threads in the base cloth (2); wherein the base cloth (2) is woven with two second conductive strips (4) parallel to the weft threads in the base cloth (2), and the two second conductive strips (4) are respectively located at both ends near the weft direction of the base cloth (2), characterized in that: The first conductive strip (3) and the second conductive strip (4) are both conductive composite yarn strips (5). The conductive composite yarn strip (5) is composed of a plurality of conductive composite yarns (50). The conductive composite yarn (50) includes S-twist conductive composite yarn (51) and Z-twist conductive composite yarn (52). The S-twist conductive composite yarn (51) and the Z-twist conductive composite yarn (52) are arranged alternately to form the conductive composite yarn (50).

2. The low electromagnetic radiation self-regulating heating cloth according to claim 1, characterized in that: The S-twist conductive composite yarn (51) is made by winding and twisting a single nickel-plated copper foil, with the twist being S-twist and a twist of 2000 TPM.

3. The low electromagnetic radiation self-regulating heating cloth according to claim 1, characterized in that: The Z-twist conductive composite yarn (52) is made by winding and twisting a single nickel-plated copper foil, with the twist being Z-twist and a twist of 2000 TPM.

4. The low electromagnetic radiation self-regulating heating cloth according to claim 1, characterized in that: The S-twist conductive composite yarn (51) includes an elastic yarn A (511) as the core yarn and a conductive filament A (512) that is spirally wound clockwise around the elastic yarn A (511).

5. The low electromagnetic radiation self-regulating heating cloth according to claim 4, characterized in that: The Z-twist conductive composite yarn (52) includes an elastic yarn B (521) as the core and a conductive filament B (522) that is spirally wound counterclockwise around the elastic yarn B (521).

6. The low electromagnetic radiation self-regulating heating cloth according to claim 5, characterized in that: The elastic yarn A (511) and the elastic yarn B (521) are 250D polyester or nylon.

7. The low electromagnetic radiation self-regulating heating cloth according to claim 5, characterized in that: The conductive wire A (512) and the conductive wire B (522) are nickel-plated copper foils; the width of the nickel-plated copper foils is 0.33 mm and the thickness is 0.03 mm.

8. The low electromagnetic radiation self-regulating heating cloth according to claim 1, characterized in that: The S-twist conductive composite yarn (51) includes a conductive elastic yarn A (513) as the core and a conductive filament C (514) that is spirally wound clockwise around the conductive elastic yarn A (513).

9. A self-regulating heating cloth with low electromagnetic radiation according to claim 8, characterized in that: The Z-twist conductive composite yarn (52) includes a conductive elastic yarn B (523) as the core and a conductive filament D (524) that is spirally wound counterclockwise around the conductive elastic yarn B (523).

10. A self-regulating heating cloth with low electromagnetic radiation according to claim 9, characterized in that: The conductive elastic yarn A (513) and the conductive elastic yarn B (523) are DDY composite conductive filaments, and the specifications of the DDY composite conductive filaments are 30D / 4f or 60D / 8f; the conductive wire C (514) and the conductive wire D (524) are nickel-plated copper foils; the width of the nickel-plated copper foils is 0.33mm and the thickness is 0.03mm.

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