Multi-layer film compounding process and device

Abstract

The invention discloses a compounding process and device of a multi-layer film. The compounding process comprises the following steps: irradiating a PET film with a clean surface for 1 min by using an ultraviolet lamp under the protection of nitrogen to generate surface free radicals; the preparation method comprises the following steps: immersing a PET film with surface free radicals into a hydroxyethyl methylacrylate solution, irradiating for 25 minutes by using an ultraviolet lamp under the protection of nitrogen to carry out grafting reaction, and introducing hydroxyl on the surface of the PET film; carrying out ultrasonic cleaning on the PET film with hydroxyl on the surface by using ethyl acetate as a cleaning agent, and drying and curing; coating two surfaces of the dried and cured PET film with glue; a BOPP film and a CPP film are compounded on the two faces of the PET film coated with the glue respectively; the composite film is cooled and cured, a grafting reaction is carried out on the surface of the PET film, hydroxyl is introduced, the surface activity of the PET film is improved, the hydrophilicity is enhanced, and therefore the bonding strength after the PET film is composited with the BOPP film and the CPP film is improved, and layering is not prone to occurring.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-layer packaging films, and in particular to a composite process and device for multi-layer films. Background Art

[0002] One type of multilayer packaging film currently available uses a PET film as a base material, onto which various functional film materials are laminated. These multilayer films are typically bonded together using glue. Conventional PET films have low surface activity and are not very hydrophilic. Conventional lamination processes involve directly coating the PET film with glue before lamination. This method of laminating multilayer films results in low interlayer bonding strength and is prone to delamination. Summary of the Invention

[0003] In order to solve the above-mentioned deficiencies in the prior art, the present invention provides a multi-layer film composite process and device.

[0004] In order to achieve the above technical effects, the present invention adopts the following scheme: A multilayer film composite process comprises the following steps: S1. Irradiate the cleaned PET film with UV light for 1 min under nitrogen protection to generate surface free radicals. S2. Immersing the PET film having surface free radicals in a hydroxyethyl methacrylate solution and irradiating it with an ultraviolet lamp for 25 minutes under nitrogen protection to perform a grafting reaction, thereby introducing hydroxyl groups on the surface of the PET film; S3, ultrasonically cleaning the PET film having hydroxyl groups on the surface using ethyl acetate as a cleaning agent, and drying and curing; S4, applying glue on both sides of the dried and cured PET film; S5. Laminating the two sides of the PET film coated with glue with BOPP film and CPP film respectively; S6. Cooling and solidifying the composite film.

[0005] A multi-layer film composite device comprises a grafting reaction mechanism, a double-sided coating mechanism and a composite mechanism which are arranged in sequence; The grafting reaction mechanism includes a chassis, which is divided into an unwinding chamber, a preparation chamber, a reaction chamber, a cleaning chamber, a drying chamber, and a winding chamber in sequence by a plurality of partitions; the chassis is provided with a first door and a second door connected to the unwinding chamber and the winding chamber respectively, and the partition is provided with a slit opening for the PET film to pass through; A first unwinding roller is provided in the unwinding chamber, and a first winding roller is provided in the winding chamber; The preparation chamber is provided with a plurality of first ultraviolet lamps respectively located above and below the PET film; A container for hydroxyethyl methacrylate solution is provided in the reaction chamber, and a plurality of second ultraviolet lamps are provided on the container; An ultrasonic cleaning machine is provided in the cleaning chamber; The drying chamber is provided with a plurality of electric heating tubes; The chassis is provided with an air inlet and an air outlet respectively connected to the unwinding chamber and the winding chamber, the air outlet is connected to an air pump, and the chassis is also provided with an air suction pipe connected to the unwinding chamber, and the air suction pipe is provided with a first valve.

[0006] A preferred technical solution is that the container is provided with a plurality of guide rollers that allow the PET film to be transported in a continuously curved path, and the container is provided with a plurality of transparent mounting tubes, the mounting tubes are arranged parallel to the guide rollers, the two ends of the mounting tubes are sealed and connected to the inner wall of the container, the mounting tubes are hollow and pass through the inner wall of the container, and the second ultraviolet lamp is arranged in the mounting tube.

[0007] According to a preferred technical solution, a plurality of hollow holes are provided on the partition.

[0008] According to a preferred technical solution, the composite mechanism includes at least two composite roller groups arranged on a frame, and each composite roller group includes two composite rollers arranged close to each other.

[0009] A preferred technical solution is that the composite roller includes a cylindrical outer shell, both ends of the outer shell are through-set, and both end surfaces of the outer shell are provided with concave steps, and end covers are matched on the steps. A main shaft extends outward from the center of the end cover, and the main shaft is rotatably arranged on the frame. A through hole connected to the outer shell is opened in the center of the main shaft, and a central cylinder is provided in the outer shell. The length of the central cylinder is shorter than the length of the outer shell. The central cylinder and the inner wall of the outer shell are spaced apart to form a hot oil interlayer, and the hot oil interlayer is connected to the through hole. The end covers at both ends of the outer shell are detachably connected to the two ends of the central cylinder.

[0010] A preferred technical solution is that a plurality of connecting columns are extended outward on the end surface of the central cylinder, and the plurality of connecting columns are evenly distributed around the center of the central cylinder. The connecting columns are against the inner side of the end cover, and the outer end of the connecting column is fixed with an outward-facing screw column, and the diameter of the screw column is smaller than the diameter of the connecting column. A connecting hole matching the screw column is opened on the end cover, and the screw column is screwed with a nut after passing through the connecting hole.

[0011] According to a preferred technical solution, a second sealing ring is fixedly provided on the outer end surface of the connecting column and surrounds the screw column, and the end cover is pressed tightly against the second sealing ring.

[0012] According to a preferred technical solution, a plurality of support columns corresponding to the connecting columns are protruding from the inner side of the end cover, and the inner ends of the support columns are provided with sockets matching the connecting columns, the connecting columns are inserted into the sockets, and the connecting holes are connected to the sockets.

[0013] According to a preferred technical solution, a first sealing ring is fixedly provided on the outer side of the step, and the end cover is pressed tightly against the first sealing ring.

[0014] Compared with the prior art, the beneficial effects are: The present invention first carries out a grafting reaction on the surface of the PET film to introduce hydroxyl groups, which is used to improve the surface activity of the PET film and enhance the hydrophilicity, thereby improving the bonding strength of the PET film after being composited with the BOPP film and the CPP film, and preventing delamination. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a cross-sectional schematic diagram of the grafting reaction mechanism in the present invention.

[0016] Figure 2 It is a schematic diagram of the container structure in the present invention.

[0017] Figure 3 It is a schematic cross-sectional view of the container in the present invention.

[0018] Figure 4 It is a schematic diagram of the composite structure of the present invention.

[0019] Figure 5 It is a schematic diagram of the composite roller structure of the present invention.

[0020] Figure 6 It is a schematic diagram of the first cross section of the composite roller in the present invention.

[0021] Figure 7 It is a second cross-sectional schematic diagram of the composite roller in the present invention.

[0022] Figure 8 It is a schematic diagram of the end cover structure of the composite roller in the present invention.

[0023] Figure 9 It is a partial structural schematic diagram of the composite roller in the present invention.

[0024] Figure 10 It is a schematic diagram of the shell structure in the present invention.

[0025] Reference numerals: 1, chassis; 2, partition; 3, slit; 4, unwinding chamber; 5, preparation chamber; 6, reaction chamber; 7, cleaning chamber; 8, drying chamber; 9, winding chamber; 10, first chamber door; 11, second chamber door; 12, unwinding roller; 13, first ultraviolet lamp; 14, container; 15, ultrasonic cleaning machine; 16, electric heating tube; 17, winding roller; 18, nitrogen tank; 19, air inlet pipe; 20, air intake pipe ; 21. Air pump; 22. Guide roller; 23. Mounting pipe; 24. Frame; 25. Composite roller; 26. Main shaft; 27. Oil inlet pipe; 28. Bracket; 29. ​​Housing; 30. End cover; 31. Shaft seal structure; 32. Nut; 33. Through hole; 34. Center cylinder; 35. Support edge; 36. Connecting column; 37. Screw column; 38. Hot oil interlayer; 39. Support column; 40. Socket; 41. Step. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described 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.

[0027] A multilayer film composite process comprises the following steps: S1. Irradiate the cleaned PET film with UV light for 1 min under nitrogen protection to generate surface free radicals to facilitate the connection of hydroxyl groups; S2. Immersing the PET film having surface free radicals in a hydroxyethyl methacrylate solution and irradiating the film with an ultraviolet lamp for 25 minutes under nitrogen protection to perform a grafting reaction, thereby introducing hydroxyl groups on the surface of the PET film and improving the surface activity of the PET film; S3, ultrasonically cleaning the PET film having hydroxyl groups on the surface using ethyl acetate as a cleaning agent, and drying and curing; S4, applying glue on both sides of the dried and cured PET film; S5. Laminating the two sides of the PET film coated with glue with BOPP film and CPP film respectively; S6. Cooling and solidifying the composite film to form a multilayer film.

[0028] The present invention first carries out a grafting reaction on the surface of the PET film to introduce hydroxyl groups, which is used to improve the surface activity of the PET film and enhance the hydrophilicity, thereby improving the bonding strength of the PET film after being composited with the BOPP film and the CPP film, and preventing delamination.

[0029] A multi-layer film composite device comprises a grafting reaction mechanism, a double-sided coating mechanism, and a composite mechanism, which are sequentially arranged. A roll of PET film is first subjected to a grafting reaction in the grafting reaction mechanism to introduce hydroxyl groups onto its surface. The PET film roll, a BOPP film roll, and a CPP film roll are then removed from the grafting reaction mechanism. The PET film roll, the BOPP film roll, and the CPP film roll are then released onto a second unwinding roller 12. The released PET film is first coated with glue on both sides in the double-sided coating mechanism, which utilizes existing technology. The released BOPP film and CPP film are then composited onto both sides of the PET film via the composite mechanism. After composited, the film is cooled and solidified. Finally, the multi-layer film is wound onto a second winding roller 17.

[0030] The grafting reaction mechanism includes a chassis 1, which is sealed and divided into a reeling chamber 4, a preparatory chamber 5, a reaction chamber 6, a cleaning chamber 7, a drying chamber 8 and a reeling chamber 9 in sequence by multiple partitions 2; the chassis 1 is provided with a first door 10 and a second door 11 connected to the reeling chamber 4 and the reeling chamber 9 respectively, and the partition 2 is provided with a slit 3 for the PET film to pass through.

[0031] A first unwinding roller 12 is provided in the unwinding chamber 4, and a first winding roller 17 is provided in the winding chamber 9. The first box door 10 is opened to place the PET film roll to be grafted onto the first unwinding roller 12, and then the PET film after the reaction is wound onto the first winding roller 17. After completion, the second box door 11 is opened to remove the PET film roll from the first winding roller 17.

[0032] The preparation chamber 5 is provided with a plurality of first ultraviolet lamps 13 respectively located above and below the PET film. The surface of the PET film is irradiated by the first ultraviolet lamps 13, thereby forming free radicals on the surface of the PET film.

[0033] The reaction chamber 6 is provided with a container 14 containing hydroxyethyl methacrylate solution, and the container 14 is provided with a plurality of second ultraviolet lamps. The PET film enters the container 14 and undergoes a grafting reaction under the irradiation of the second ultraviolet lamps.

[0034] An ultrasonic cleaning machine 15 is provided in the cleaning chamber 7. The ultrasonic cleaning machine 15 adopts the existing technology. The cleaning agent in the ultrasonic cleaning machine 15 is ethyl acetate solution to clean the PET film.

[0035] The drying chamber 8 is provided with a plurality of electric heating tubes 16 , which generate high temperature for drying the cleaned PET film.

[0036] The chassis 1 is provided with an air inlet and an air outlet respectively connected to the unwinding chamber 4 and the winding chamber 9, the air outlet is connected to an air pump 21, and the chassis 1 is further provided with an air intake pipe 20 connected to the unwinding chamber 4, the air intake pipe 20 is provided with a first valve, the air inlet is connected to the nitrogen tank 18 through the air intake pipe 19, the air intake pipe 19 is provided with a second valve, the nitrogen tank 18 is installed on the chassis 1, and the air outlet is connected to the exhaust pipe through the air pump 21. During the reaction process, the first valve is closed and the second valve is opened. Under the drive of the air pump 21, the nitrogen in the nitrogen tank 18 is sucked into the chassis 1 and flows within the chassis 1, and finally discharged from the air outlet and the exhaust pipe, thereby filling the chassis 1 with a flowing nitrogen atmosphere. After the reaction is completed, the second valve is closed and the first valve is opened. Under the drive of the air pump 21, air is sucked into the chassis 1 from the air intake pipe 20 to replace the nitrogen atmosphere within the chassis 1.

[0037] The PET film to be grafted is placed on the first unwinding roller 12, and the housing 1 is filled with a flowing nitrogen atmosphere. The PET film is then released and enters the preparation chamber 5 where it is irradiated by the first ultraviolet lamp 13 to form free radicals. The PET film is then sent to the reaction chamber 6, and the PET film is sent to the container 14 to be immersed in hydroxyethyl methacrylate. Under the irradiation of the second ultraviolet lamp, a grafting reaction is performed to connect the hydroxyl groups. The PET film is then sent to the cleaning chamber and cleaned in an ultrasonic cleaning machine 15 filled with ethyl acetate solution. After cleaning, the PET film is sent to the drying chamber 8 and dried at the high temperature of the electric heating tube 16. After drying, the PET film is sent to the winding chamber 9 for winding. Since the grafting reaction of the PET film in the container 14 takes time, the PET film is intermittently conveyed in the housing 1.

[0038] A preferred technical solution is that the container 14 is provided with a plurality of guide rollers 22 that allow the PET film to be transported in a continuously curved path, and the container 14 is provided with a plurality of transparent mounting tubes 23. The mounting tubes 23 are arranged parallel to the guide rollers 22, and both ends of the mounting tubes 23 are sealed and connected to the inner wall of the container 14. The mounting tubes 23 are hollow and pass through the inner wall of the container 14, and the second ultraviolet lamp is arranged in the mounting tubes 23.

[0039] This solution facilitates the installation of the second ultraviolet lamp tube, and the second ultraviolet lamp tube is set below the liquid level of hydroxyethyl methacrylate. The arrangement of several second ultraviolet lamp tubes needs to enable both sides of the PET film to be irradiated.

[0040] In a preferred technical solution, a plurality of hollow holes are provided on the partition plate 2 to facilitate the flow of nitrogen.

[0041] According to a preferred technical solution, the composite mechanism includes at least two groups of composite rollers 25 arranged on a frame 24 , and each group of composite rollers 25 includes two composite rollers 25 arranged adjacent to each other.

[0042] After the BOPP film and the CPP film are respectively attached to both sides of the PET film, they are squeezed between two laminating rollers 25 to perform compression lamination.

[0043] The preferred technical solution is that the composite roller 25 includes a cylindrical shell 29, both ends of the shell 29 are through-set, and both end surfaces of the shell 29 are provided with a concave step 41, and the step 41 is matched with an end cover 30, and a main shaft 26 extends outward from the center of the end cover 30, and the main shaft 26 is rotatably set on the frame 24. The center of the main shaft 26 is provided with a through hole 33 connected to the shell 29, and a central cylinder 34 is provided in the shell 29. The length of the central cylinder 34 is shorter than the length of the shell 29, and the central cylinder 34 is spaced from the inner wall of the shell 29 to form a hot oil interlayer 38, and the hot oil interlayer 38 is connected to the through hole 33. The end covers 30 at both ends of the shell 29 are detachably connected to the two ends of the central cylinder 34.

[0044] To improve lamination quality and prevent the glue from cooling during lamination, the laminating roller 25 needs to be heated. In this solution, the two main shafts 26 at either end of the housing 29 are connected to the oil inlet pipe 27 and the oil outlet pipe, respectively, via a shaft seal mechanism. The oil inlet pipe 27 and the oil outlet pipe are secured to the frame 24 via a bracket 28. During the lamination process, hot oil is fed from the oil inlet pipe 27 and the through-hole 33 at one end into the hot oil interlayer 38, filling the hot oil interlayer 38 and thereby heating the housing 29. The hot oil then flows out of the through-hole 33 at the other end, passing through the hot oil interlayer 38 and maintaining the housing 29 at a constant temperature.

[0045] A number of support edges 35 are protruding from the inner wall of the outer shell 29. The support edges 35 rest against the central cylinder 34, which can not only increase the load strength of the outer shell 29, but also limit the central cylinder 34 to the center of the outer shell 29 through the area surrounded by the several support edges 35. The end covers 30 at both ends are then pressed onto the steps 41 at both ends of the outer shell 29 and connected to the central cylinder 34, so that the outer shell 29, the central cylinder 34 and the end covers 30 can be detachably arranged for easy maintenance.

[0046] A preferred technical solution is that a plurality of connecting columns 36 are extended outward from the end surface of the central cylinder 34, and the plurality of connecting columns 36 are evenly distributed around the center of the central cylinder 34. The connecting columns 36 are against the inner side of the end cover 30, and the outer end of the connecting column 36 is fixed with an outward-facing screw column 37, and the diameter of the screw column 37 is smaller than the diameter of the connecting column 36. A connecting hole matching the screw column 37 is opened on the end cover 30, and the screw column 37 is screwed with a nut 32 after passing through the connecting hole.

[0047] In this way, the central cylinder 34 and the end cover 30 are detachably connected.

[0048] In a preferred technical solution, a second sealing ring is fixedly provided on the outer end surface of the connecting column 36 and surrounds the screw column 37 , and the end cover 30 is pressed tightly against the second sealing ring.

[0049] According to a preferred technical solution, a plurality of support columns 39 corresponding to the connecting columns 36 are protruded from the inner side of the end cover 30, and the inner ends of the support columns 39 are provided with sockets matching the connecting columns 36, the connecting columns 36 are inserted into the sockets, and the connecting holes are connected to the sockets.

[0050] The support column 39 and the end cover 30 are integrally formed, thereby improving the connection strength between the connecting column 36 and the end cover 30 .

[0051] In a preferred technical solution, a first sealing ring is fixedly provided on the outer side of the step 41 , and the end cover 30 is pressed tightly against the first sealing ring.

[0052] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. These are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0054] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present invention.

Claims

1. A multi-layer film composite process, characterized in that: The following steps are involved: S1. Irradiate the cleaned PET film with UV light for 1 min under nitrogen protection to generate surface free radicals. S2. Immersing the PET film having surface free radicals in a hydroxyethyl methacrylate solution and irradiating it with an ultraviolet lamp for 25 minutes under nitrogen protection to perform a grafting reaction, thereby introducing hydroxyl groups on the surface of the PET film; S3, ultrasonically cleaning the PET film having hydroxyl groups on the surface using ethyl acetate as a cleaning agent, and drying and curing; S4, applying glue on both sides of the dried and cured PET film; S5. Laminating the two sides of the PET film coated with glue with BOPP film and CPP film respectively; S6. Cooling and solidifying the composite film.

2. A multi-layer film composite device, characterized in that: A composite process for the multilayer film according to claim 1, comprising a grafting reaction mechanism, a double-sided coating mechanism, and a composite mechanism arranged in sequence; The grafting reaction mechanism comprises a chassis (1), wherein the chassis (1) is divided into an unwinding chamber (4), a preparatory chamber (5), a reaction chamber (6), a cleaning chamber (7), a drying chamber (8), and a winding chamber (9) in sequence by a plurality of partitions (2); a first door (10) and a second door (11) are provided on the chassis (1), which are connected to the unwinding chamber (4) and the winding chamber (9), respectively; and a slit opening (3) for the PET film to pass through is provided on the partition (2); A first unwinding roller (12) is provided in the unwinding chamber (4), and a first winding roller (17) is provided in the winding chamber (9); The preparation chamber (5) is provided with a plurality of first ultraviolet lamp tubes (13) respectively located above and below the PET film; A container (14) containing a hydroxyethyl methacrylate solution is provided in the reaction chamber (6), and a plurality of second ultraviolet lamps are provided on the container (14); An ultrasonic cleaning machine (15) is provided in the cleaning chamber (7); A plurality of electric heating tubes (16) are provided in the drying chamber (8); The chassis (1) is provided with an air inlet and an air outlet respectively connected to the unwinding chamber (4) and the winding chamber (9), the air outlet is connected to an air pump (21), and the chassis (1) is also provided with an air suction pipe (20) connected to the unwinding chamber (4), and the air suction pipe (20) is provided with a first valve.

3. The multi-layer film composite process and device according to claim 2, characterized in that: The container (14) is provided with a plurality of guide rollers (22) for transporting the PET film in a continuously curved path. The container (14) is provided with a plurality of transparent mounting tubes (23). The mounting tubes (23) are arranged parallel to the guide rollers (22). Both ends of the mounting tubes (23) are sealed and connected to the inner wall of the container (14). The mounting tubes (23) are hollow and pass through the inner wall of the container (14). The second ultraviolet lamp is arranged in the mounting tubes (23).

4. The multi-layer film composite process and device according to claim 2, characterized in that: The partition (2) is provided with a plurality of hollow holes.

5. The multi-layer film composite process and device according to claim 2, characterized in that: The composite mechanism comprises at least two groups of composite roller (25) wheel sets arranged on a frame (24), and each group of composite roller (25) wheel sets comprises two composite rollers (25) arranged adjacent to each other.

6. The multi-layer film composite process and device according to claim 5, characterized in that: The composite roller (25) includes a cylindrical shell (29), both ends of the shell (29) are through-set, and both end surfaces of the shell (29) are provided with concave steps (41), and the steps (41) are matched with end covers (30), and a main shaft (26) extends outward from the center of the end cover (30), and the main shaft (26) is rotatably set on the frame (24), and a through hole (33) connected to the shell (29) is opened at the center of the main shaft (26), and a central cylinder (34) is provided in the shell (29), and the length of the central cylinder (34) is shorter than the length of the shell (29), and the central cylinder (34) and the inner wall of the shell (29) are spaced apart to form a hot oil interlayer (38), and the hot oil interlayer (38) is connected to the through hole (33), and the end covers (30) at both ends of the shell (29) are detachably connected to the two ends of the central cylinder (34).

7. The multi-layer film composite process and device according to claim 6, characterized in that: A plurality of connecting columns (36) are provided on the end surface of the central cylinder (34) extending outward. The plurality of connecting columns (36) are evenly distributed around the center of the central cylinder (34). The connecting columns (36) abut against the inner side of the end cover (30). An outward-facing screw column (37) is fixed to the outer end of the connecting column (36). The diameter of the screw column (37) is smaller than the diameter of the connecting column (36). A connecting hole matching the screw column (37) is provided on the end cover (30). The screw column (37) passes through the connecting hole and is screwed with a nut (32).

8. The multi-layer film composite process and device according to claim 7, characterized in that: A second sealing ring is fixedly provided on the outer end surface of the connecting column (36) and surrounds the screw column (37). The end cover (30) is pressed tightly against the second sealing ring.

9. The multi-layer film composite process and device according to claim 7, characterized in that: The inner side of the end cover (30) is provided with a plurality of support columns (39) corresponding to the connecting columns (36), and the inner ends of the support columns (39) are provided with sockets matching the connecting columns (36). The connecting columns (36) are inserted into the sockets, and the connecting holes are connected to the sockets.

10. The multi-layer film composite process and device according to claim 1, characterized in that: A first sealing ring is fixedly provided on the outer side of the step (41), and the end cover (30) is pressed tightly against the first sealing ring.

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