Preparation method of biaxially oriented polypropylene touch film

Abstract

The invention discloses a preparation method of a biaxially oriented polypropylene touch film. The preparation method comprises the following specific steps: S1, preparing raw materials; s2, raw material mixing: mixing a base layer raw material and an elastic coating raw material; s3, coating with a coating machine: extruding the mixed raw materials of the base layer through the coating machine; s4, coating: stretching the base layer raw material by a stretcher to prepare a base layer, and coating the surface of the base layer with an elastic coating; s5, performing excimer UV lamp irradiation: performing pretreatment by using a curing device and using a 172nm excimer light source; s6, irradiating with a high-pressure mercury lamp: irradiating with a conventional mercury lamp; s7, curing: after irradiation by a conventional mercury lamp, standing and waiting for complete curing to obtain the bidirectional sec-polypropylene elastic film; and S8, rolling: rolling the biaxially oriented polypropylene elastic film. The preparation method of the biaxially oriented polypropylene touch film disclosed by the invention has the effects of improving the solvent resistance and wear resistance of a coating and optimizing the appearance and quality stability of a product at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of biaxially stretched polypropylene touch films, and in particular to a preparation method of biaxially stretched polypropylene touch films. Background Art

[0002] Polypropylene touch film is a processing method that changes the surface treatment of polypropylene film to give it different tactile effects. Tactile film has a wide range of applications and can be used in packaging, printing, bag making and other fields. By changing the tactile effect, the appearance, touch and use experience of the product are enhanced, and the product's attractiveness and brand value are improved. In addition, the tactile film process can achieve a variety of effects, such as frosted, suede, leather, pearlescent, etc., to meet the needs of different customers and markets.

[0003] During the production process of polypropylene touch film, excessive wrinkles may be formed during the surface treatment. If there are too many wrinkles on the surface, it will directly affect the appearance, strength and quality stability of the finished product. Summary of the invention

[0004] The present invention discloses a method for preparing a biaxially oriented polypropylene touch film, which aims to solve the technical problem that too many wrinkles may be formed when the surface is treated, and if there are too many wrinkles on the surface, the appearance, strength and quality stability of the finished product will be directly affected.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing a biaxially oriented polypropylene touch film comprises the following specific steps:

[0007] S1: Raw material configuration: Use polypropylene, styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, nano calcium carbonate, paraffin, titanate coupling agent, toughening agent, anti-adhesive masterbatch, antistatic masterbatch, etc. to adjust the base material formula; use water-based polyurethane emulsion, styrene-acrylate copolymer emulsion, triethylamine, ammonia water, silicon dioxide, dipropylene glycol methyl ether, alcohol ester twelve, polyether polyurethane thickener, defoamer, silicone surfactant, water-based isocyanate curing agent, thermoplastic polyurethane elastomer, homopolypropylene, homopolyethylene, maleic anhydride grafted polyolefin, hydroxy ester of olefin, and water to adjust the elastic coating formula;

[0008] S2: Raw material mixing: mixing base material and elastic coating material;

[0009] S3: Coating by coater: The mixed base material is extruded through the coater;

[0010] S4: coating: the base material is stretched by a stretching machine to form a base, and an elastic coating is applied on the surface of the base;

[0011] S5: Excimer light source irradiation: Use a curing device to pre-treat with a 172nm excimer light source;

[0012] S6: Mercury lamp irradiation: conventional mercury lamp irradiation is used again;

[0013] S7: Curing: After being irradiated by a conventional mercury lamp, it is left to stand and wait for complete curing to obtain a biaxially stretched polypropylene elastic film;

[0014] S8: Rolling up: rolling up the biaxially stretched polypropylene elastic film.

[0015] Through the synthesis of tactile coatings, the self-extinction method can be used to obtain a biaxially oriented polypropylene tactile film. By adjusting the mass ratio or type of the hard segment and the soft segment, a tactile coating with different properties can be obtained. The introduction of photocuring functional groups can improve the solvent resistance and wear resistance of the coating. During the surface treatment, it is first pretreated with a 172nm excimer light source. Due to the high energy of the excimer light source and the penetration depth of 100-500nm, only a very thin layer is cured to produce shrinkage and wrinkles, and floats on the uncured coating. Subsequently, the biaxially oriented polypropylene tactile film is formed after being irradiated by a conventional mercury lamp and completely cured. This can reduce the generation of wrinkles and the overall shrinkage of the film, thereby optimizing the product appearance and quality stability.

[0016] In a preferred embodiment, the curing device includes a light-shielding chamber, and the polypropylene touch film is guided into the light-shielding chamber through a coating machine, and an excimer UV lamp and a high-pressure mercury lamp are arranged in the light-shielding chamber, and a hot air blower is installed at the top of the light-shielding chamber;

[0017] The output end of the hot air blower passes through the top of the light-shielding chamber, the top inner wall of the light-shielding chamber is fixedly connected with an I-shaped bracket, and the I-shaped bracket is located directly below the hot air blower. The I-shaped bracket is also located between the excimer UV lamp and the high-pressure mercury lamp, and a filter is provided on one inner wall of the I-shaped bracket;

[0018] The top inner wall of the light-shielding chamber is fixedly connected with a lamp holder 1, and the excimer UV lamp is installed on the lamp holder 1, and the outer walls on both sides facing each other are respectively fixedly connected with a light shielding plate 1;

[0019] The top inner wall of the light-shielding bin is fixedly connected to a linear guide rail, and a slider is movably connected to the linear guide rail. The bottom end of the slider is fixedly connected to a second lamp holder, and a high-pressure mercury lamp is installed on the second lamp holder. A second light shielding plate is fixedly connected to an outer wall of one side of the second lamp holder.

[0020] A vent 1 is provided on one side of the I-shaped bracket, and an inner C-shaped bracket is provided on one side of the vent 1; a vent 2 is provided on one side of the shading plate 2, and an outer C-shaped bracket is provided on one side of the vent 2; the outer C-shaped bracket is movably sleeved outside the inner C-shaped bracket;

[0021] A support frame is fixed to the inner wall of the outer C-shaped bracket, and a plurality of fan guides are installed on the support frame. A light guide mechanism is arranged on one side of the second lamp bracket.

[0022] By providing a curing device, in the curing device, the pulled acrylic tactile film enters the light-shielding chamber and passes under the excimer UV lamp and the high-pressure mercury lamp in sequence. Among them, by providing a linear guide rail, the curing time after the excimer UV lamp irradiation can be adapted to the use of films of different materials. By providing a hot air blower, the wind force can be dispersed through the filter during the hot air flow, so as to avoid wrinkles on the surface of the acrylic tactile film caused by excessive wind force, and at the same time make the hot air distribution more uniform. Through the guidance of the ventilator, the hot air can flow evenly through the surface of the acrylic tactile film, optimizing the efficiency of one round of curing. The hot air is guided to one side of the high-pressure mercury lamp to achieve full utilization of the hot air, and can assist in improving the curing efficiency of the acrylic tactile film again after the high-pressure mercury lamp irradiation.

[0023] In a preferred solution, the light guide mechanism includes a support plate, and one side of the support plate is fixedly connected to a silver reflector and a white reflector at the same time through a connecting frame, and the white reflector is arranged on the outer side of the silver reflector;

[0024] The two opposite sides of the lamp frame 2 are respectively fixedly connected with mirror frames through side frames, and two reflecting mirrors are respectively installed on each mirror frame.

[0025] A light-guiding mechanism is provided in which the light of the high-pressure mercury lamp can be reflected by reflectors arranged on both sides, and the light is respectively reflected to the center of the silver-surface reflector and the white-surface reflector. After being reflected by the two, the light can be vertically irradiated to the surface of the acrylic tactile film. Since the reflectivity of the silver-surface reflector is higher than that of the white-surface reflector and the light is lost during the reflection process, the acrylic tactile film can present a gradually decreasing light effect after passing through the high-pressure mercury lamp. Therefore, only a longer high-pressure mercury lamp is required to complete the light reduction for a certain distance, thereby optimizing the curing efficiency and reducing the cost expenditure.

[0026] As can be seen from the above, a method for preparing a biaxially oriented polypropylene touch film includes the following specific steps: S1: raw material configuration: using polypropylene, styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, nano calcium carbonate, paraffin, titanate coupling agent, toughening agent, anti-adhesive masterbatch, antistatic masterbatch and the like to adjust the base material formula; using water-based polyurethane emulsion, styrene-acrylate copolymer emulsion, triethylamine, ammonia water, silicon dioxide, dipropylene glycol methyl ether, alcohol ester twelve, polyether polyurethane thickener, defoamer, silicone surfactant, water-based isocyanate curing agent, thermoplastic polyurethane elastomer, homopolymer polypropylene, homopolymer polyethylene, maleic anhydride grafted Polyolefin, hydroxy ester of olefinic acid, water-adjustable elastic coating formula; S2: raw material mixing: mixing base material and elastic coating material; S3: coating by coater: extruding the mixed base material through coater; S4: coating: the base material is stretched by a stretching machine to form a base, and an elastic coating is coated on the surface of the base; S5: excimer UV lamp irradiation: pre-treatment with a 172nm excimer light source using a curing device; S6: high-pressure mercury lamp irradiation: then irradiation with a conventional mercury lamp; S7: curing: after irradiation with a conventional mercury lamp, standing and waiting for complete curing to obtain a biaxially stretched polypropylene elastic film; S8: winding: winding the biaxially stretched polypropylene elastic film. The preparation method of the biaxially stretched polypropylene touch film provided by the present invention has the technical effect of improving the solvent resistance and wear resistance of the coating, while optimizing the product appearance and quality stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention provides an overall flow chart of a method for preparing a biaxially oriented polypropylene touch film.

[0028] Figure 2 The present invention provides a schematic diagram of the appearance structure of a curing device for preparing a biaxially oriented polypropylene touch film.

[0029] Figure 3 The present invention provides a schematic diagram of the internal structure of a curing device for preparing a biaxially oriented polypropylene touch film.

[0030] Figure 4 This is a schematic diagram of the connection structure of an outer C-shaped bracket and an inner C-shaped bracket in a method for preparing a biaxially oriented polypropylene touch film proposed in the present invention.

[0031] Figure 5 The present invention provides a schematic diagram of the structure of a light guide mechanism for the method for preparing a biaxially oriented polypropylene touch film.

[0032] In the figure: 1. light shielding chamber; 2. hot air blower; 3. light shielding plate 1; 4. lamp holder 1; 5. excimer UV lamp; 6. I-type bracket; 7. filter; 8. inner C-type bracket; 9. outer C-type bracket; 10. light shielding plate 2; 11. high pressure mercury lamp; 12. lamp holder 2; 13. light guide mechanism; 14. slider; 15. linear guide rail; 16. vent 1; 17. support frame; 18. fan guide; 19. vent 2; 1301. support plate; 1302. connecting frame; 1303. white reflector; 1304. reflector; 1305. silver reflector; 1306. mirror frame; 1307. side frame. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0034] The method for preparing a biaxially stretched polypropylene tactile film disclosed in the present invention is mainly used in the scenario of preparing a biaxially stretched polypropylene tactile film.

[0035] Reference Figure 1 , a method for preparing a biaxially oriented polypropylene touch film, comprising the following specific steps:

[0036] S1: Raw material configuration: Use polypropylene, styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, nano calcium carbonate, paraffin, titanate coupling agent, toughening agent, anti-adhesive masterbatch, antistatic masterbatch, etc. to adjust the base material formula; use water-based polyurethane emulsion, styrene-acrylate copolymer emulsion, triethylamine, ammonia water, silicon dioxide, dipropylene glycol methyl ether, alcohol ester twelve, polyether polyurethane thickener, defoamer, silicone surfactant, water-based isocyanate curing agent, thermoplastic polyurethane elastomer, homopolypropylene, homopolyethylene, maleic anhydride grafted polyolefin, hydroxy ester of olefin, and water to adjust the elastic coating formula;

[0037] S2: Raw material mixing: mixing base material and elastic coating material;

[0038] S3: Coating by coater: The mixed base material is extruded through the coater;

[0039] S4: coating: the base material is stretched by a stretching machine to form a base, and an elastic coating is applied on the surface of the base;

[0040] S5: Excimer light source irradiation: Use a curing device to pre-treat with a 172nm excimer light source;

[0041] S6: Mercury lamp irradiation: conventional mercury lamp irradiation is used again;

[0042] S7: Curing: After being irradiated by a conventional mercury lamp, it is left to stand and wait for complete curing to obtain a biaxially stretched polypropylene elastic film;

[0043] S8: Winding: The biaxially stretched polypropylene elastic film is rolled up. Through the synthesis of the tactile coating, the self-extinction method can be used to obtain the biaxially stretched polypropylene tactile film. By adjusting the mass ratio or type of the hard segment and the soft segment, tactile coatings with different properties are obtained. The photocuring functional groups are introduced to improve the solvent resistance and wear resistance of the coating. During the surface treatment, it is first pretreated with a 172nm excimer light source. Due to the high energy of the excimer light source and the penetration depth of 100-500nm, only a very thin layer is cured to produce shrinkage and wrinkles, and floats on the uncured coating. Subsequently, the biaxially stretched polypropylene tactile film is formed after being irradiated by a conventional mercury lamp and completely cured. This can reduce the generation of wrinkles and the overall shrinkage of the film, thereby optimizing the product appearance and quality stability.

[0044] Reference Figure 2 and Figure 3 In a preferred embodiment, the curing equipment includes a light-shielding chamber 1, and the polypropylene touch film is guided into the light-shielding chamber 1 through a coater, and a quasi-molecular UV lamp 5 and a high-pressure mercury lamp 11 are simultaneously arranged in the light-shielding chamber 1, and a hot air blower 2 is installed at the top of the light-shielding chamber 1.

[0045] Reference Figure 3 and Figure 4 In a preferred embodiment, the output end of the hot air blower 2 passes through the top of the light-shielding chamber 1, and the top inner wall of the light-shielding chamber 1 is fixedly connected with an I-shaped bracket 6, and the I-shaped bracket 6 is located directly below the hot air blower 2. The I-shaped bracket 6 is also located between the excimer UV lamp 5 and the high-pressure mercury lamp 11, and a filter 7 is provided on the inner wall of one side of the I-shaped bracket 6.

[0046] Reference Figure 3 In a preferred embodiment, the top inner wall of the shading chamber 1 is fixedly connected to a lamp holder 4, and the excimer UV lamp 5 is installed on the lamp holder 4, and the outer walls on both sides of the lamp holder 4 facing each other are fixedly connected to a shading plate 3 respectively.

[0047] Reference Figure 3 In a preferred embodiment, the top inner wall of the shading bin 1 is fixedly connected to a linear guide rail 15, and a slider 14 is movably connected to the linear guide rail 15, the bottom end of the slider 14 is fixedly connected to a lamp holder 12, and the high-pressure mercury lamp 11 is installed on the lamp holder 12, and a shading plate 10 is fixedly connected to one side outer wall of the lamp holder 12.

[0048] Reference Figure 4In a preferred embodiment, a vent 16 is provided on one side of the I-shaped bracket 6, and an inner C-shaped bracket 8 is provided on one side of the vent 16, a vent 2 19 is provided on one side of the visor 10, and an outer C-shaped bracket 9 is provided on one side of the vent 2 19, and the outer C-shaped bracket 9 is movably connected to the outside of the inner C-shaped bracket 8.

[0049] Reference Figure 3 and Figure 4 In a preferred embodiment, a support frame 17 is fixed to the inner wall of the outer C-shaped bracket 9, and a plurality of ventilating fans 18 are installed on the support frame 17. A light guide mechanism 13 is provided on one side of the lamp frame 12. In the curing device, the traction acrylic touch film enters the light shielding chamber 1 and passes under the excimer UV lamp 5 and the high-pressure mercury lamp 11 in sequence. The position of the high-pressure mercury lamp 11 can be changed by providing a linear guide rail 15 to change the distance between the high-pressure mercury lamp 11 and the excimer UV lamp 5, thereby changing the curing time after irradiation by the excimer UV lamp 5 to adapt to the use of films of different materials. By providing the hot air blower 2, the hot air is blown by The filter screen 7 passes through the top of the I-shaped bracket 6 to act on the surface of the propylene touch film, and is guided by multiple fan guides 18 to allow the hot air to pass through the inner C-shaped bracket 8 and the outer C-shaped bracket 9 and be transmitted to one side of the high-pressure mercury lamp 11. As a result, the wind force can be dispersed through the filter screen 7 to avoid excessive wind force causing wrinkles on the surface of the propylene touch film, and at the same time, the hot air can be distributed more evenly. After being guided by the fan guides 18, the hot air can flow evenly through the surface of the propylene touch film to optimize the efficiency of one round of curing. The hot air is guided to one side of the high-pressure mercury lamp 11 to fully utilize the hot air, and can again assist in improving the curing efficiency of the propylene touch film after irradiation by the high-pressure mercury lamp 11.

[0050] Reference Figure 5 In a preferred embodiment, the light guide mechanism 13 includes a support plate 1301 , and one side of the support plate 1301 is fixedly connected to a silver reflector 1305 and a white reflector 1303 through a connecting frame 1302 , and the white reflector 1303 is arranged on the outer side of the silver reflector 1305 .

[0051] Reference Figure 5In a preferred embodiment, the two opposite sides of the lamp frame 12 are respectively fixedly connected with a frame 1306 through a side frame 1307, and two reflectors 1304 are respectively installed on each frame 1306. In the light guide mechanism 13, the reflectors 1304 arranged on both sides can reflect the light of the high-pressure mercury lamp 11. Based on the setting angle of the reflectors 1304, the outer reflectors 1304 and the inner reflectors 1304 can reflect the light to the silver reflector 1305 and the white reflector 1304 respectively. At the center position, the light can be reflected by the two to make it irradiate vertically to the surface of the acrylic tactile film. Since the reflectivity of the silver-surface reflector 1305 is higher than that of the white-surface reflector 1304, the light extending from one side of the high-pressure mercury lamp 11 can be gradually reduced from strong to weak. At the same time, based on the loss of light in the reflection process, the acrylic tactile film can present a gradually decreasing light effect after passing through the high-pressure mercury lamp 11. Therefore, only a longer high-pressure mercury lamp 11 is needed to complete the light reduction for a certain distance, which can optimize the curing efficiency and reduce cost expenditure.

[0052] Working principle: Through the synthesis of tactile coatings, the self-extinction method can be used to obtain a biaxially oriented polypropylene tactile film. By adjusting the mass ratio or type of the hard segment and the soft segment, tactile coatings with different properties are obtained. The introduction of photocurable functional groups improves the solvent resistance and wear resistance of the coating. During the surface treatment, it is first pre-treated with a 172nm excimer light source. Due to the high energy of the excimer light source and the penetration depth of 100-500nm, only a very thin layer is cured to produce shrinkage and wrinkles, and floats on the uncured coating. Subsequently, the biaxially oriented polypropylene tactile film is formed after being irradiated by a conventional mercury lamp and completely cured, which is recognized to reduce the generation of wrinkles and the shrinkage of the entire film. degree, thereby optimizing the product appearance and quality stability. In the curing equipment, the pulled acrylic touch film enters the light shielding chamber 1 and passes under the excimer UV lamp 5 and the high-pressure mercury lamp 11 in sequence. The position of the high-pressure mercury lamp 11 can be changed by providing a linear guide 15 to change the distance between the high-pressure mercury lamp 11 and the excimer UV lamp 5, thereby changing the curing time after being irradiated by the excimer UV lamp 5 to adapt to the use of films of different materials. Through the setting of the hot air blower 2, the hot air passes through the filter 7 from the top of the I-shaped bracket 6 to act on the surface of the acrylic touch film, and is guided by a plurality of guide fans 18 to pass through the inner C-shaped bracket 8 and the outer C-shaped bracket 9, and The hot air is transmitted to one side of the high-pressure mercury lamp 11, thereby the wind force can be dispersed through the filter 7 to avoid excessive wind force causing wrinkles on the surface of the acrylic touch film, and at the same time, the hot air distribution is more uniform. After being guided by the fan 18, the hot air can flow evenly through the surface of the acrylic touch film, optimizing the efficiency of one round of curing. The hot air is guided to one side of the high-pressure mercury lamp 11 to achieve full utilization of the hot air, which can help improve the curing efficiency of the acrylic touch film again after the high-pressure mercury lamp 11 irradiates. In the light guide mechanism 13, the light of the high-pressure mercury lamp 11 can be reflected by the reflectors 1304 arranged on both sides. Based on the setting angle of the reflector 1304, the outer reflector 1304 can be set to 04 and the inner reflector 1304 reflect the light to the center of the silver reflector 1305 and the white reflector 1304 respectively, and then the light can be vertically irradiated to the surface of the acrylic touch film after being reflected by the two. Since the reflectivity of the silver reflector 1305 is higher than that of the white reflector 1304, the light extending from one side of the high-pressure mercury lamp 11 can be gradually reduced from strong to weak. At the same time, based on the loss of light in the reflection process, the acrylic touch film can present a gradually decreasing light effect after passing through the high-pressure mercury lamp 11. Therefore, only a longer high-pressure mercury lamp 11 is required to complete the light reduction for a certain distance, which can optimize the curing efficiency and reduce cost expenditure.

[0053] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a biaxially oriented polypropylene touch film, characterized in that: The specific steps include: S1: Raw material configuration: Use polypropylene, styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, nano calcium carbonate, paraffin, titanate coupling agent, toughening agent, anti-adhesive masterbatch, antistatic masterbatch, etc. to adjust the base material formula; use water-based polyurethane emulsion, styrene-acrylate copolymer emulsion, triethylamine, ammonia water, silicon dioxide, dipropylene glycol methyl ether, alcohol ester twelve, polyether polyurethane thickener, defoamer, silicone surfactant, water-based isocyanate curing agent, thermoplastic polyurethane elastomer, homopolypropylene, homopolyethylene, maleic anhydride grafted polyolefin, hydroxy ester of olefin, and water to adjust the elastic coating formula; S2: Raw material mixing: mixing base material and elastic coating material; S3: Coating by coater: The mixed base material is extruded through the coater; S4: coating: the base material is stretched by a stretching machine to form a base, and an elastic coating is applied on the surface of the base; S5: Excimer light source irradiation: Use curing equipment to pre-treat with 172nm excimer light source. Due to the high energy of the excimer light source and the penetration depth of 100-500nm, only a very thin layer is cured to produce shrinkage and wrinkles, and float on the uncured coating; S6: Mercury lamp irradiation: conventional mercury lamp irradiation is used again; S7: Curing: After being irradiated by a conventional mercury lamp, it is left to stand and wait for complete curing to obtain a biaxially stretched polypropylene elastic film; S8: Rolling up: rolling up the biaxially stretched polypropylene elastic film.

2. The method for preparing a biaxially oriented polypropylene touch film according to claim 1, characterized in that: The curing device comprises a light-shielding chamber (1), and the polypropylene touch film is guided into the light-shielding chamber (1) through a coating machine, and an excimer UV lamp (5) and a high-pressure mercury lamp (11) are simultaneously arranged in the light-shielding chamber (1), and a hot air blower (2) is installed at the top of the light-shielding chamber (1).

3. The method for preparing a biaxially oriented polypropylene touch film according to claim 2, characterized in that: The output end of the hot air blower (2) passes through the top of the light-shielding chamber (1); the inner wall of the top of the light-shielding chamber (1) is fixedly connected to an I-shaped bracket (6); the I-shaped bracket (6) is located directly below the hot air blower (2); the I-shaped bracket (6) is also located between the excimer UV lamp (5) and the high-pressure mercury lamp (11); and a filter screen (7) is provided on one inner wall of the I-shaped bracket (6).

4. The method for preparing a biaxially oriented polypropylene touch film according to claim 3, characterized in that: The top inner wall of the light-shielding chamber (1) is fixedly connected to a lamp holder (4), and the excimer UV lamp (5) is installed on the lamp holder (4). The outer walls on both sides facing each other of the lamp holder (4) are respectively fixedly connected to a light-shielding plate (3).

5. The method for preparing a biaxially oriented polypropylene touch film according to claim 4, characterized in that: The top inner wall of the light-shielding bin (1) is fixedly connected to a linear guide rail (15), and a slider (14) is movably connected to the linear guide rail (15), the bottom end of the slider (14) is fixedly connected to a second lamp holder (12), and a high-pressure mercury lamp (11) is mounted on the second lamp holder (12), and a second light-shielding plate (10) is fixedly connected to an outer wall on one side of the second lamp holder (12).

6. The method for preparing a biaxially oriented polypropylene touch film according to claim 5, characterized in that: One side of the I-shaped bracket (6) is provided with a vent 1 (16), and one side of the vent 1 (16) is provided with an inner C-shaped bracket (8); one side of the shading plate 2 (10) is provided with a vent 2 (19), and one side of the vent 2 (19) is provided with an outer C-shaped bracket (9); the outer C-shaped bracket (9) is movably sleeved on the outside of the inner C-shaped bracket (8).

7. The method for preparing a biaxially oriented polypropylene touch film according to claim 6, characterized in that: A support frame (17) is fixed to the inner wall of the outer C-shaped bracket (9), and a plurality of ducting fans (18) are installed on the support frame (17). A light guiding mechanism (13) is arranged on one side of the second lamp frame (12).

8. The method for preparing a biaxially oriented polypropylene touch film according to claim 7, characterized in that: The light guide mechanism (13) comprises a support plate (1301), and one side of the support plate (1301) is simultaneously fixedly connected to a silver-surface reflective plate (1305) and a white-surface reflective plate (1303) via a connecting frame (1302), and the white-surface reflective plate (1303) is arranged on the outside of the silver-surface reflective plate (1305).

9. The method for preparing a biaxially oriented polypropylene touch film according to claim 8, characterized in that: The two opposite sides of the lamp frame 2 (12) are respectively fixedly connected with mirror frames (1306) through side frames (1307), and two reflectors (1304) are respectively installed on each mirror frame (1306).

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