Production process of excimer PET (Polyethylene Terephthalate) film

Abstract

The invention relates to the technical field of PET (Polyethylene Terephthalate) films, and particularly discloses a production process of an excimer PET film, which comprises the following steps of: feeding PET slice raw materials to a crystallization bed after passing through a feeding bin and a drying overhead stock bin, and crystallizing and drying; conveying the crystallized and dried slices to a screw extruder for melting, and blowing the extruded slices into a film shape through a film blowing pipe; stretching and shaping the film-shaped PET film, and cutting the film-shaped PET film into a specific length or width; uniformly coating the surface of the PET film with a UV coating; and irradiating the surface of the PET film by using an excimer light beam. Excimer light beams are utilized to irradiate the surface of the PET film to achieve the effect of curing the UV coating, the effects of enhancing the surface hardness and wear resistance of the PET film, improving the surface glossiness and transparency of the PET film, improving the adhesive force of the PET film and the UV coating and achieving environment-friendly and energy-saving green production are achieved, high energy of the excimer light beams excites chemical bonds of the UV coating to be rapidly cured, and a hard protective layer is formed. The anti-scraping capability is obviously improved; the service life is obviously prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of PET films, and in particular discloses a production process of a quasi-molecular PET film. Background Art

[0002] Excimer technology is a technology that uses excimer beams to treat the surface of materials. In the production process of excimer PET film, excimer beam treatment is closely related to the use of UV coating, which is a coating that can be quickly cured under ultraviolet light. In the excimer treatment process, the UV coating is evenly coated on the surface of the PET film, and then the UV coating is cured on the surface of the PET film to form an extremely thin film through the irradiation of the excimer ultraviolet lamp. However, the existing production of PET film still needs to be improved, so a production process of excimer PET film is provided. Summary of the invention

[0003] In order to overcome the shortcomings and deficiencies in the prior art, the object of the present invention is to provide a production process for excimer PET film.

[0004] To achieve the above object, a production process of a quasi-molecular PET film of the present invention specifically comprises the following steps: S1: PET chips are fed into the crystallization bed through the feeding bin and the drying high-level bin for crystallization and drying; S2: conveying the crystallized and dried slices to a screw extruder for melting, extrusion and blowing into a film through a film blowing tube; S3: stretching and shaping the thin PET film and cutting it into a specific length or width; S4: Apply UV coating evenly on the surface of PET film; S5: irradiating the surface of the PET film with an excimer beam.

[0005] Preferably, the excimer beam is emitted by an excimer laser, the wavelength emitted by the excimer laser is between 100nm and 400nm, and the energy of the photons in the excimer beam is between 3.1eV and 12.4eV, which has multiple functions such as high-precision processing, non-contact processing, high efficiency and environmental protection, and flexible control of processing parameters. These functions jointly realize the miniaturization and high-precision of the surface treatment of the PET film, avoid the damage that may be caused by traditional processing, improve production efficiency and meet environmental protection requirements, and at the same time, can flexibly adjust the processing parameters according to specific needs to achieve diversified processing effects on the surface of the PET film.

[0006] Preferably, the environment in which the working area of ​​the surface of the PET film is irradiated by the excimer beam is an inert gas environment, which has the effect of preventing oxidation and contamination of the surface of the PET film, and achieves the effect of improving the processing quality and surface performance of the PET film. In the process of irradiating the surface of the PET film with the excimer beam, the inert gas environment can effectively isolate oxygen, moisture and other impurities in the air, thereby preventing the surface of the PET film from being oxidized or contaminated during the processing, which can not only maintain the cleanliness of the surface of the PET film, but also reduce surface defects caused by oxidation and contamination, such as scratches, spots, etc., thereby improving the processing quality and surface performance of the PET film. At the same time, the inert gas environment also helps to maintain the stability and energy output of the excimer beam, ensuring the accuracy and consistency of the processing process.

[0007] Preferably, the mechanism used to irradiate the surface of the PET film with an excimer light beam is an excimer curing mechanism, and a seal is provided at the end of the excimer curing mechanism to ensure the purity of the curing environment, effectively prevent external air, dust and impurities from entering the curing area, and avoid the influence of pollutants on the curing process, thereby achieving high-quality curing of the PET film surface and improving the product yield and performance stability; at the same time, the seal also prevents the leakage of inert gas, ensures the efficient use of the light beam energy, improves the curing efficiency, and plays a role in safety protection, avoiding direct contact of operators with high-energy light beams and ensuring operational safety. In addition, the coordinated work of the seal and the curing mechanism realizes customized modification of the surface properties of the PET film. For example, by adjusting the curing parameters and sealing conditions, PET film products with different gloss, hardness and hydrophilicity can be prepared to meet the needs of different application scenarios.

[0008] Preferably, the seal is made of graphite packing / thermoplastic rubber. The graphite packing can ensure excellent sealing performance under high temperature, high pressure and corrosive environment due to its excellent resistance to high temperature, high pressure and corrosion, and effectively prevent external contaminants from entering the curing area, thereby maintaining the purity of the curing process and ensuring high-quality curing of the PET film surface. Thermoplastic rubber has good elasticity and resilience, and can form a tight and stable seal at the end of the curing mechanism. Even in the face of deformation or vibration during the curing process, it can quickly return to its original state, continuously maintain the sealing efficiency, and ensure efficient use of beam energy.

[0009] Preferably, the seal is in the form of a long strip, and a plurality of lips are arranged at one end of the seal close to the PET film. The long strip design of the seal and the configuration of the plurality of lips together enhance the sealing performance and achieve efficient isolation of the curing environment. The lips are closely attached to the surface of the PET film to form an effective sealing barrier, effectively preventing the entry of external air, dust, impurities and potential pollutants, and ensuring the purity and stability of the PET film during the curing process. At the same time, this design also improves the adaptability and flexibility of the seal, so that it can better adapt to PET films of different shapes and sizes, as well as various installation conditions at the end of the curing mechanism.

[0010] Preferably, the lip on the seal is inclined relative to the moving direction of the PET film. The inclined lip can better adapt to the movement of the PET film, ensuring a continuous and stable sealing contact between the lip and the PET film. When the lip is subjected to the dynamic pressure generated by the movement of the PET film, the lip can utilize the component force generated by its inclination angle to fit more closely to the PET film, effectively preventing leakage. This not only improves the sealing reliability, but also achieves effective protection of the PET film in a dynamic environment, avoiding poor curing or contamination problems caused by leakage. At the same time, the inclined lip design also helps to reduce the friction between the lip and the PET film, thereby extending the service life of the seal and reducing maintenance costs.

[0011] Preferably, the pre-crystallized polyester chips are melted at high temperature, the melt is extruded through a screw extruder, and impurities and bubbles in the melt are removed to ensure the purity and uniformity of the body, the extruded melt is blown into a film through a film blowing tube, and the film is quickly cooled and kept flat through a cooling and traction device. The cooling adopts a cooling roller and / or air cooling method. The function of the high-temperature melted pre-crystallized polyester chips is to soften them and make them fluid, which is convenient for subsequent extrusion molding. This step realizes the transformation of the polyester raw material into a processable melt. The process of extruding the melt through a screw extruder can accurately control the pressure and flow of the melt to ensure continuous and uniform extrusion of the melt. At the same time, the shearing action during the screw extrusion process helps to further mix and homogenize the melt, remove impurities and bubbles in the melt, realize the purification and homogenization of the melt, and improve the quality of the film. The technical means of blowing the pure and uniform melt into a film through a film blowing tube can quickly expand the melt into a film form, realize the transformation from melt to film form, and lay the foundation for subsequent cooling and shaping. Finally, the film is quickly cooled by cooling rollers and / or air cooling, and the traction device is used to keep the film flat. This can quickly reduce the temperature of the film and quickly shape it while maintaining the flatness and dimensional stability of the film, thereby achieving rapid cooling and shaping of the film and high-quality output.

[0012] Preferably, the PET film is cut into specific lengths or widths as needed, and the shaped PET film is rolled into a roll for subsequent use and transportation. The technical role of cutting the PET film to a specific length or width is to meet the specific requirements of different application scenarios for the film size, thereby achieving precise customization of the film size. At the same time, the technical means of rolling the shaped PET film into a roll not only facilitates the subsequent use and processing of the film, such as printing, lamination and other processes, but also greatly facilitates the transportation and storage of the film, reduces the occupied space, and reduces logistics costs.

[0013] Preferably, the cutting waste generated in the production process is classified and processed, and then the cutting waste is cleaned and crushed before being transported to a screw extruder for melting utilization. The purpose of classifying and processing the cutting waste is to effectively distinguish waste of different materials and different degrees of pollution, so as to facilitate subsequent targeted cleaning and treatment. This step realizes the resource pretreatment of the waste and improves the recycling rate of the waste. By cleaning the waste, stains, oil stains and other impurities attached to the surface of the waste can be removed, and the purity of the waste can be improved, laying a good foundation for subsequent crushing and melting utilization. Crushing the waste can reduce the volume of the waste and increase its surface area, which is convenient for the melting treatment of the screw extruder, and also helps to improve the melting efficiency and product quality. Finally, the cleaned and crushed waste is transported to the screw extruder for melting utilization, which can convert the waste into reusable raw materials, realize the recycling of the waste, save the cost of raw materials, and reduce environmental pollution.

[0014] The beneficial effects of the present invention are as follows: the surface of the PET film is irradiated with an excimer beam to cure the UV coating, thereby achieving the effect of enhancing the surface hardness and wear resistance of the PET film, improving the surface gloss and transparency of the PET film, improving the adhesion between the PET film and the UV coating, and achieving a green production effect of environmental protection and energy saving. The high energy of the excimer beam excites the chemical bonds of the UV coating to rapidly solidify, forming a hard protective layer, and significantly improving the scratch resistance and service life; at the same time, the surface microstructure of the PET film is optimized, defects are reduced, and the gloss is more uniform and the transparency is higher; the surface polarity can also be improved, the adhesion of the coating can be enhanced, and shedding or cracking can be prevented; and the curing process does not require heating or chemical catalysts, thereby reducing energy consumption and waste emissions, and is in line with the concepts of green production and sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A process flow chart of a production process of an excimer PET film; Figure 2 This is a structural flow chart of the surface treatment of PET film. DETAILED DESCRIPTION

[0016] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0017] Example 1 In this embodiment, a production process of a quasi-molecular PET film specifically includes the following steps: S1: PET chips are fed into the crystallization bed through the feeding bin and the drying high-level bin for crystallization and drying; S2: conveying the crystallized and dried slices to a screw extruder for melting, extrusion and blowing into a film through a film blowing tube; S3: stretching and shaping the thin PET film and cutting it into a specific length or width; S4: Apply UV coating evenly on the surface of PET film; S5: irradiating the surface of the PET film with an excimer beam.

[0018] Specifically, the use of excimer beams to irradiate the surface of the PET film has the effect of curing the UV coating, thereby enhancing the surface hardness and wear resistance of the PET film, improving the surface gloss and transparency of the PET film, improving the adhesion between the PET film and the UV coating, and achieving a green production effect of environmental protection and energy saving. The high energy of the excimer beam excites the chemical bonds of the UV coating to quickly solidify and form a hard protective layer, which significantly improves the scratch resistance and service life; at the same time, it optimizes the surface microstructure of the PET film, reduces defects, makes the gloss more uniform and the transparency higher; it can also improve the surface polarity, enhance the adhesion of the coating, and prevent falling off or cracking; and the curing process does not require heating or chemical catalysts, which reduces energy consumption and waste emissions, and is in line with the concept of green production and sustainable development.

[0019] Specifically, the excimer beam is emitted by an excimer laser, the wavelength emitted by the excimer laser is between 100nm and 400nm, and the energy of the photons in the excimer beam is between 3.1eV and 12.4eV, which has multiple functions such as high-precision processing, non-contact processing, high efficiency and environmental protection, and flexible control of processing parameters. These functions jointly realize the miniaturization and high-precision of PET film surface treatment, avoid the damage that may be caused by traditional processing, improve production efficiency and meet environmental protection requirements, and at the same time, can flexibly adjust processing parameters according to specific needs to achieve diversified processing effects on the PET film surface.

[0020] Specifically, the working area of ​​the PET film surface irradiated by the excimer beam is in an inert gas environment, which has the effect of preventing oxidation and contamination of the PET film surface, thereby achieving the effect of improving the processing quality and surface performance of the PET film. In the process of irradiating the PET film surface with the excimer beam, the inert gas environment can effectively isolate oxygen, moisture and other impurities in the air, thereby preventing the PET film surface from being oxidized or contaminated during the processing, which can not only maintain the cleanliness of the PET film surface, but also reduce surface defects caused by oxidation and contamination, such as scratches, spots, etc., thereby improving the processing quality and surface performance of the PET film. At the same time, the inert gas environment also helps to maintain the stability and energy output of the excimer beam, ensuring the accuracy and consistency of the processing process.

[0021] Specifically, the inert gas is preferably helium.

[0022] Specifically, the mechanism used to irradiate the surface of the PET film with an excimer light beam is an excimer curing mechanism. A seal is provided at the end of the excimer curing mechanism to ensure the purity of the curing environment, effectively prevent external air, dust and impurities from entering the curing area, and avoid the influence of pollutants on the curing process, thereby achieving high-quality curing of the PET film surface and improving the product yield and performance stability; at the same time, the seal also prevents the leakage of inert gas, ensures the efficient use of the light beam energy, improves the curing efficiency, and plays a role in safety protection, avoiding direct contact between operators and high-energy light beams, and ensuring operational safety. In addition, the coordinated work of the seal and the curing mechanism realizes customized modification of the surface properties of the PET film. For example, by adjusting the curing parameters and sealing conditions, PET film products with different gloss, hardness and hydrophilicity can be prepared to meet the needs of different application scenarios.

[0023] Specifically, the excimer curing mechanism is also provided with a mass spectrometer leak detector, such as a helium mass spectrometer leak detector, which is installed at the inlet and outlet of the PET film to detect in real time whether the inert gas is leaking and the leakage concentration.

[0024] Specifically, the seal is made of graphite packing / thermoplastic rubber. Graphite packing can ensure excellent sealing performance under high temperature, high pressure and corrosive environment due to its excellent resistance to high temperature, high pressure and corrosion, and effectively prevent external contaminants from entering the curing area, thereby maintaining the purity of the curing process and ensuring high-quality curing of the PET film surface. Thermoplastic rubber has good elasticity and recovery, and can form a tight and stable seal at the end of the curing mechanism. Even in the face of deformation or vibration during the curing process, it can quickly return to its original state, continuously maintain sealing performance, and ensure efficient utilization of beam energy.

[0025] Specifically, the seal is in the form of a long strip, and a plurality of lips are arranged at one end of the seal close to the PET film. The long strip design of the seal and the configuration of the plurality of lips together enhance the sealing performance and achieve efficient isolation of the curing environment. The lips are closely attached to the surface of the PET film to form an effective sealing barrier, effectively preventing the entry of external air, dust, impurities and potential pollutants, and ensuring the purity and stability of the PET film during the curing process. At the same time, this design also improves the adaptability and flexibility of the seal, so that it can better adapt to PET films of different shapes and sizes, as well as various installation conditions at the end of the curing mechanism.

[0026] Specifically, the lip on the seal is inclined relative to the moving direction of the PET film. The inclined lip can better adapt to the movement of the PET film, ensuring a continuous and stable sealing contact between the lip and the PET film. When the lip is subjected to the dynamic pressure generated by the movement of the PET film, the lip can utilize the component force generated by its inclination angle to fit more closely to the PET film, effectively preventing leakage. This not only improves the sealing reliability, but also achieves effective protection of the PET film in a dynamic environment, avoiding poor curing or contamination problems caused by leakage. At the same time, the inclined lip design also helps to reduce the friction between the lip and the PET film, thereby extending the service life of the seal and reducing maintenance costs.

[0027] Specifically, the pre-crystallized polyester chips are melted at high temperature, the melt is extruded through a screw extruder, and impurities and bubbles in the melt are removed to ensure the purity and uniformity of the body, the extruded melt is blown into a film through a film blowing tube, and the film is quickly cooled and kept flat through a cooling and traction device. The cooling adopts a cooling roller and / or air cooling method. The function of the high-temperature melted pre-crystallized polyester chips is to soften them and make them fluid, which is convenient for subsequent extrusion molding. This step realizes the transformation of polyester raw materials into processable melts. The process of extruding the melt through a screw extruder can accurately control the pressure and flow of the melt to ensure continuous and uniform extrusion of the melt. At the same time, the shearing action during the screw extrusion process helps to further mix and homogenize the melt, remove impurities and bubbles in the melt, realize the purification and homogenization of the melt, and improve the quality of the film. The technical means of blowing the pure and uniform melt into a film through a film blowing tube can quickly expand the melt into a film form, realize the transformation from melt to film form, and lay the foundation for subsequent cooling and shaping. Finally, the film is quickly cooled by cooling rollers and / or air cooling, and the traction device is used to keep the film flat. This can quickly reduce the temperature of the film and quickly shape it while maintaining the flatness and dimensional stability of the film, thereby achieving rapid cooling and shaping of the film and high-quality output.

[0028] Specifically, the screw rod is an auger-shaped screw rod, and the spiral blades on the screw rod are also provided with a feeding hole.

[0029] Specifically, the PET film is cut into specific lengths or widths as needed, and the shaped PET film is rolled into a roll for subsequent use and transportation. The technical role of cutting the PET film to a specific length or width is to meet the specific requirements of different application scenarios for the film size, and to achieve precise customization of the film size. At the same time, the technical means of rolling the shaped PET film into a roll not only facilitates the subsequent use and processing of the film, such as printing, lamination and other processes, but also greatly facilitates the transportation and storage of the film, reduces the occupied space, and reduces logistics costs.

[0030] Specifically, the cutting waste generated in the production process is classified and processed, and then the cutting waste is cleaned and crushed before being transported to a screw extruder for melting. The purpose of classifying and processing the cutting waste is to effectively distinguish waste of different materials and different degrees of pollution, so as to facilitate subsequent targeted cleaning and treatment. This step realizes the resource pretreatment of the waste and improves the recycling rate of the waste. By cleaning the waste, stains, oil and other impurities attached to the surface of the waste can be removed, and the purity of the waste can be improved, laying a good foundation for subsequent crushing and melting utilization. Crushing the waste can reduce the volume of the waste and increase its surface area, which is convenient for the melting treatment of the screw extruder, and also helps to improve the melting efficiency and product quality. Finally, the cleaned and crushed waste is transported to the screw extruder for melting utilization, which can convert the waste into reusable raw materials, realize the recycling of the waste, save the cost of raw materials, and reduce environmental pollution.

[0031] Example 2 In this embodiment, a production process of a quasi-molecular PET film specifically includes the following steps: S1: PET chips are fed into the crystallization bed through the feeding bin and the drying high-level bin for crystallization and drying; S2: conveying the crystallized and dried slices to a screw extruder for melting, extrusion and blowing into a film through a film blowing tube; S3: stretching and shaping the thin PET film and cutting it into a specific length or width; S4: Apply UV coating evenly on the surface of PET film; S5: Scan and emboss the surface of the PET film using a laser embossing device; S6: Irradiate the surface of the PET film with an excimer beam.

[0032] Specifically, in S5, the PET film is preheated before laser embossing to improve the plasticity of the material and the absorption efficiency of the laser.

[0033] Specifically, after the laser embossing is completed in S5, the PET film is cooled to preliminarily fix the embossed pattern and prevent thermal deformation, and the embossing quality is checked by an external detection module to ensure that the pattern is clear, continuous and free of defects.

[0034] Specifically, laser embossing utilizes the high energy density of the laser beam. When the laser irradiates the surface of the PET film material, the material absorbs the laser energy and converts it into heat energy. This heat energy will cause the local temperature of the material surface to rise, and the material surface will undergo physical and chemical changes such as local melting, solidification, vaporization or peeling, thereby achieving the embossing effect.

[0035] Specifically, an absorption and filtering device is also provided behind the laser embossing (i.e., in the conveying direction of the PET film), and the absorption and filtering device is used to recycle the waste materials partially vaporized or peeled off from the surface of the material.

[0036] Specifically, when the laser embossing operation is located in the working area where the excimer beam irradiates the surface of the PET film, the absorption and filtering device can not only ensure the purity of the gas in the area, but also re-input the filtered gas to ensure internal gas circulation and accelerate the local initial solidification of the material surface.

[0037] The rest of the content of this embodiment is the same as that of Embodiment 1 and will not be repeated here.

[0038] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A production process for excimer PET film, characterized in that: The specific steps include: S1: PET chips are fed into the crystallization bed through the feeding bin and the drying high-level bin for crystallization and drying; S2: Melting and extruding the crystallized and dried slices into a film; S3: stretching and shaping the thin PET film and cutting it into a specific length or width; S4: Apply UV coating evenly on the surface of PET film; S5: irradiating the surface of the PET film with an excimer beam.

2. The production process of a quasi-molecular PET film according to claim 1, characterized in that: The excimer beam is emitted by an excimer laser, the wavelength emitted by the excimer laser is between 100nm and 400nm, and the energy of the photons in the excimer beam is between 3.1eV and 12.4eV.

3. The production process of a quasi-molecular PET film according to claim 1, characterized in that: The working area where the excimer beam irradiates the surface of the PET film is located in an inert gas environment.

4. The production process of a quasi-molecular PET film according to claim 1, characterized in that: The mechanism used to irradiate the surface of the PET film with an excimer beam is an excimer curing mechanism, and a sealing member is provided at the end of the excimer curing mechanism.

5. The production process of a quasi-molecular PET film according to claim 4, characterized in that: The seal is made of graphite packing / thermoplastic rubber.

6. The production process of a quasi-molecular PET film according to claim 4, characterized in that: The sealing member is in the form of a long strip, and one end of the sealing member close to the PET film is provided with a plurality of lips.

7. The production process of a quasi-molecular PET film according to claim 6, characterized in that: The lip on the seal is arranged obliquely compared to the moving direction of the PET film.

8. The production process of a quasi-molecular PET film according to claim 1, characterized in that: The pre-crystallized polyester chips are melted at high temperature, extruded through a screw extruder, and impurities and bubbles in the melt are removed to ensure the purity and uniformity of the melt. The extruded melt is blown into a film through a film blowing tube, and the film is quickly cooled and kept flat through a cooling and traction device. The cooling adopts a cooling roller and / or air cooling method.

9. The production process of a quasi-molecular PET film according to claim 8, characterized in that: The PET film is cut into specific lengths or widths as needed, and the shaped PET film is rolled into rolls for subsequent use and transportation.

10. The production process of a quasi-molecular PET film according to claim 9, characterized in that: The cutting waste generated during the production process is classified and processed, and then the cutting waste is cleaned, crushed and transported to the screw extruder for melting and utilization.

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