Anti-fingerprint liquid medicine continuous evaporation method suitable for continuous coating of flexible film

Abstract

An anti-fingerprint liquid medicine continuous evaporation method suitable for flexible film continuous coating comprises the steps that in a vacuum coating chamber, a rolled anti-fingerprint liquid medicine belt (30) is installed on an unwinding roller (21) and a winding roller (22) and engaged with a rotating drum (10) of a driving mechanism, and a first liquid medicine storage block (32) on the liquid medicine belt is located on a molybdenum boat of an evaporation resisting module (40); and after vacuumizing, the evaporation resisting module is started, heating evaporation is conducted, and heating is stopped until the liquid medicine is completely evaporated. After the molybdenum boat is cooled, the motor is started, the rotary drum rotates, the plated flexible film product is automatically wound, meanwhile, the liquid medicine belt moves forwards, and the next liquid medicine storage block moves into the molybdenum boat; and the blank to-be-plated flexible film sample is moved into the film plating chamber, and the evaporation resisting module starts evaporation again. When the rotating drum rotates by the same radian every time, the liquid medicine belt moves forwards at equal intervals, repeated film coating is conducted in the same vacuum environment, stopping liquid medicine adding, repeated vacuum breaking and vacuum pumping are not needed, efficiency is greatly improved, and product quality is stable and good.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum coating, and in particular to an anti-fingerprint film evaporation method suitable for a continuous coating process of a flexible film. Background Art

[0002] With the emergence of 3D curved screens and foldable electronic products, the demand for flexible protective films that match them is increasing. Compared with traditional tempered films, flexible protective films have stronger plasticity and safety in protecting the surface of flexible electronic products, that is, they can fit the screen more perfectly, and will not produce fragments and cause additional damage when broken.

[0003] The substrate of the flexible protective film is generally made of plastic materials such as PET. As a protective film that is in direct contact with consumers when used, the flexible protective film needs to be smooth, scratch-resistant, and easy to wipe fingerprints. Therefore, the flexible protective film also needs to be coated with a hydrophobic and oleophobic anti-fingerprint film layer on the outermost layer. However, the difference from the tempered film coating process of the glass substrate is that, in order to improve the coating efficiency, the flexible protective film is usually coated in a whole roll, and then divided into rolls and die-cut after coating. In the existing technology for evaporation of anti-fingerprint coatings, the anti-fingerprint solution is usually prepared into anti-fingerprint particles according to the size of the coating chamber. Under a vacuum environment, the perfluoropolyether siloxane molecules in the anti-fingerprint particles are attached to the surface of the coated substrate by anti-evaporation heating to form an anti-fingerprint film layer. Usually, the anti-fingerprint particles are replaced once for one batch of products. However, in the roll-to-roll coating process, traditional anti-fingerprint particle coating is used. It is usually impossible to complete the coating of the entire roll by placing the anti-fingerprint particles once. The anti-fingerprint particles need to be constantly opened and replaced. Therefore, the vacuum will be constantly broken and vacuumed, which is not only inefficient, but also difficult to control the film-forming effect of the anti-fingerprint film on the roll.

[0004] Therefore, developing a new evaporation method for anti-fingerprint solution to meet the requirements of roll-to-roll continuous coating of flexible films is an urgent problem to be solved. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a continuous evaporation method for anti-fingerprint solution suitable for flexible film winding continuous coating, which does not require opening the cabin to replace the anti-fingerprint solution before the entire roll of coating is completed to improve efficiency and maintain stable coating quality.

[0006] In order to solve the above problems, the present invention provides a method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films, which is characterized by comprising the following steps:

[0007] S1. Open the hatch of the vacuum coating equipment and place the rolled anti-fingerprint tape on the unwinding roller of the unwinding mechanism;

[0008] S2, pull out the grid-shaped stainless steel conveyor belt with a blank front end of the anti-fingerprint solution belt from the unwinding roller and flatten it, pass it through the two ends of the steam-resistant module also fixed in the furnace, and engage with the rotating drum of the driving mechanism, and then use a fixing rod to fix the front end of the anti-fingerprint solution belt on the winding roller, and then place the first solution storage block on the grid-shaped stainless steel conveyor belt just in the molybdenum boat of the steam-resistant module;

[0009] S3. Place the flexible film product to be plated, close the hatch, and start vacuuming. The vacuum degree reaches 5×10 -3 Pa;

[0010] S4, the resistance wire in the anti-evaporation module is heated, and the anti-fingerprint solution in the solution storage block above it reaches the evaporation point, gasifies and moves, and adheres to the surface of the flexible film product to be plated; at this time, the film thickness monitor monitors the film thickness of the anti-fingerprint film layer deposited on the product surface;

[0011] S5. When the curve of the film thickness monitor returns to zero, it means that the anti-fingerprint solution in the solution storage block has evaporated completely. The heating of the anti-evaporation module can be stopped, and the molybdenum boat can be left to cool down to below the evaporation point of the anti-fingerprint solution.

[0012] S6, the motor drives the drum to rotate, driving the winding roller and the unwinding roller to rotate at the same time, and the coated flexible film product passes through the tension roller and is sent to the winding roller for winding; at the same time, the anti-fingerprint solution belt moves forward, just moving the next solution storage block into the molybdenum boat; the drum rotates the same arc each time, so that the anti-fingerprint solution belt moves forward at equal intervals;

[0013] S7, the next blank flexible film sample to be plated is moved into the coating chamber, and the steam resistance module is turned on for heating again;

[0014] S8. Repeat steps S4 to S7 until the continuous coating of the flexible film is completed.

[0015] As a further preferred embodiment, the step S5 is allowed to stand for 10 minutes; and the step S7 is confirmed through an observation window that the position of the medicine storage block is accurately located in the molybdenum boat of the anti-evaporation module.

[0016] As a preferred embodiment, a continuous evaporation device having the following structure is provided in the vacuum coating equipment, including:

[0017] A driving mechanism, the driving mechanism comprising a motor and a rotating drum driven by the motor, wherein the surface of the rotating drum is serrated;

[0018] The unwinding and rewinding mechanism includes an unwinding roller, a rewinding roller, and a tension roller;

[0019] The anti-fingerprint liquid belt is mainly a mesh-shaped stainless steel conveyor belt, one end of which is wound on the unwinding roller and the other end is wound on the winding roller, passing through a tension roller in the middle, and the mesh on the mesh-shaped stainless steel conveyor belt can be engaged with the saw teeth of the rotating drum; a plurality of liquid storage blocks are evenly installed on the mesh-shaped stainless steel conveyor belt;

[0020] The steam resistance module comprises a resistance wire and a heating molybdenum boat adapted to the medicine storage block;

[0021] A fixed bracket, used to fix the motor, the drum, the unwinding roller, the winding roller, the tension roller and the steam-proof module;

[0022] The control module has a control panel arranged outside the vacuum chamber and is electrically connected to the motor and the resistance wire to control their switching.

[0023] A further preferred technical solution is that a connecting ring or nut is welded on the grid-like stainless steel conveyor belt, and the medicine storage block is square with through holes at the four corners, which are connected to the connecting ring or nut on the grid-like stainless steel conveyor belt through screws or fixing pins or iron wire or steel wire.

[0024] The medicine storage block is 1-2 mm wider than both sides of the grid-shaped stainless steel conveyor belt.

[0025] The interval between two adjacent medicine storage blocks on the grid-shaped stainless steel conveyor belt is 50 mm.

[0026] The solution storage block is a stainless steel micro-wire felt dripped with anti-fingerprint solution.

[0027] The size of the medicine storage block is 50mm×50mm×2mm.

[0028] The molybdenum boat is a flat molybdenum boat with 3mm limits on both sides, and its two ends are open, accommodating the medicine storage block 32 which is limited within the two sides of the molybdenum boat and can pass through the two ends of the molybdenum boat.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] In the existing roll-to-roll coating process, the traditional anti-fingerprint particle coating is used. It is usually impossible to complete the coating of the entire roll by placing the anti-fingerprint particles once. It is necessary to constantly open the cabin to replace the anti-fingerprint particles, plate a furnace of products for one or two minutes, then release the vacuum, and then evacuate again. Even if the vacuum pump is well maintained and operates well, it takes more than an hour, and then evaporate the next furnace of products for one or two minutes, and then release the vacuum again and evacuate for more than an hour... This cycle is repeated, and the vacuum is constantly broken and evacuated. A roll of flexible film usually requires continuous evaporation of more than 20 furnaces, which takes more than 20 hours, and the efficiency is very low; the film-forming effect of the anti-fingerprint film layer on the roll is also difficult to control. The anti-fingerprint solution continuous evaporation method of the present invention adopts a continuous evaporation device placed in a vacuum chamber, and several anti-fingerprint solution storage blocks are arranged at equal intervals on a grid-shaped stainless steel conveyor belt, and are placed in a furnace in a roll. The solution storage blocks arrive at the fixed position of the molybdenum boat along the conveyor belt, and the molybdenum boat heats the solution storage blocks to achieve evaporation. One solution storage block evaporates one furnace. After one furnace is completed, it only needs to stay for about 10 minutes to wait for the molybdenum boat to cool down, and then the motor can be started to drive the rotating drum to rotate, so that the next solution storage block runs to the molybdenum boat for the next furnace evaporation, eliminating the time of repeatedly breaking the vacuum and evacuating the vacuum. It only takes about 5 hours to continuously plate 20 furnaces, truly realizing the "continuous" coating of the anti-fingerprint solution in the vacuum chamber, without the need to frequently open and close the cabin door, and replace the coating material, the efficiency is greatly improved, and the stability of the coating quality is also improved. In the continuous evaporation device of the anti-fingerprint solution of the present invention, the solution storage block is easy to disassemble and recycle. The invention discloses an anti-fingerprint liquid continuous coating process, which adopts a large-area block evaporation source to ensure that the anti-fingerprint liquid AF is volatilized and dispersed evenly and the film layer is deposited evenly. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the principle of the continuous evaporation device used in the present invention.

[0032] Figure 2 This is a schematic diagram of the winding and unwinding of the continuous evaporation device used in the present invention.

[0033] Figure 3 Schematic diagram of the heating module of the continuous evaporation device used in the present invention

[0034] Figure 4 This is a schematic diagram of the meshed stainless steel conveyor belt and the rotating drum of the continuous evaporation device used in the present invention.

[0035] The technical features correspond to the reference numerals as follows:

[0036] Rotating drum 10 , unwinding and rewinding mechanism 20 , unwinding roller 21 , rewinding roller 22 , anti-fingerprint solution belt 30 , mesh stainless steel conveyor belt 31 , solution storage block 32 , screw 33 , steam-proof module 40 . DETAILED DESCRIPTION

[0037] The technical solutions of the preferred embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0038] Reference Figure 1-4 As shown, a continuous evaporation device used in a continuous evaporation method of anti-fingerprint solution for continuous coating of flexible films of the present invention is provided. The device is provided with a fixed bracket on a base in a coating chamber, on which a motor, a rotating drum 10, a unwinding roller 21, a winding roller 22, a tension roller and an anti-evaporation module 40 are installed. The motor and the rotating drum 10 serve as a driving mechanism, and the rotating drum 10 is installed on the output shaft of the motor and is driven by the motor to rotate, and the surface of the rotating drum is serrated.

[0039] The unwinding roller 21, the winding roller 22, and the tension roller (which belongs to the prior art and is not shown in the figure) serve as the unwinding and winding mechanism 30. The anti-fingerprint solution belt 30 is installed on the unwinding and winding mechanism 20. The main body of the anti-fingerprint solution belt 30 is a mesh-shaped stainless steel conveyor belt 31, one end of which is wound on the unwinding roller 21 and the other end is wound on the winding roller 22, and passes through the tension roller in the middle; and the mesh on the mesh-shaped stainless steel conveyor belt 31 can mesh with the serrations of the rotating drum 10.

[0040] Along the length direction of the grid-like stainless steel conveyor belt 31, a number of medicine storage blocks 32 are evenly installed at intervals. The installation method is that a connecting ring or a nut is welded on the grid-like stainless steel conveyor belt 31. The medicine storage block 32 is square and has through holes at the four corners. Screws 33 or fixing pins or iron wires or steel wires pass through the through holes and are connected to the connecting rings or nuts on the grid-like stainless steel conveyor belt 31.

[0041] The solution storage block 32 is a stainless steel micro-wire felt dripped with anti-fingerprint solution, and is preferably a large-area block evaporation source with a size of 50mm×50mm×2mm to ensure the uniform dispersion of the anti-fingerprint solution AF; the interval between two adjacent solution storage blocks 32 on the grid-shaped stainless steel conveyor belt 31 is 50mm. The solution storage block 32 is 1-2mm wider than the two sides of the grid-shaped stainless steel conveyor belt 31, mainly to better locate the position of the solution storage block on the molybdenum boat. On the one hand, the size just matches the molybdenum boat and can be stuck on the molybdenum boat. On the other hand, it also increases the contact area between the molybdenum boat and the solution storage block, increases the heating surface, and improves the steam resistance efficiency.

[0042] According to the prior art, the anti-evaporation module 40 includes a resistance wire and a molybdenum boat. The preferred molybdenum boat of the present invention is a flat molybdenum boat with 3mm high limit baffles on both sides, which is adapted to the medicine storage block 32. The flat molybdenum boat has open ends to accommodate the medicine storage block 32, which is limited between the limit baffles on both sides of the molybdenum boat and can pass through the two ends of the molybdenum boat.

[0043] The continuous evaporation device is also provided with a control module, and its control panel is arranged outside the vacuum chamber and is electrically connected to the motor and the resistance wire to control their switching, which is the same as the control method in the prior art.

[0044] The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films of the present invention comprises the following steps:

[0045] S1. Open the door of the vacuum coating equipment and install the rolled anti-fingerprint solution tape 30 on the unwinding roller 21 of the unwinding mechanism 20;

[0046] S2, pull out the grid-shaped stainless steel conveyor belt 31 with a blank front end (i.e., without the solution storage block 32) of the anti-fingerprint solution belt 30 from the unwinding roller 21, flatten it, pass it through the openings at both ends of the molybdenum boat of the anti-evaporation module 40, mesh the grid-shaped stainless steel conveyor belt 31 with the rotating drum 10 of the driving mechanism, fix the front end of the anti-fingerprint solution belt 30 on the winding roller 22 with a fixing rod, and then adjust the grid-shaped stainless steel conveyor belt 31 so that the first solution storage block 33 thereon is just located on the molybdenum boat of the anti-evaporation module 40;

[0047] S3, according to the flexible film winding and unwinding method in the prior art, the flexible film product to be plated is placed, the hatch is closed, and vacuuming is started, and the vacuum degree reaches 5×10 -3 Pa. In the prior art, an unwinding chamber and a winding chamber can be arranged on both sides of the coating chamber, and an isolation valve can be installed between the unwinding chamber, the winding chamber and the coating chamber. When the isolation valve is opened, the flexible film material passes through the extremely narrow slit on the isolation valve, moves and winds in the unwinding chamber-coating chamber-winding chamber, and after the flexible film moves into place, the isolation valve is closed.

[0048] S4, the resistance wire in the anti-evaporation module 40 is heated, and the anti-fingerprint solution in the solution storage block 33 above it reaches the evaporation point, gasifies and moves, and adheres to the surface of the flexible film product to be plated; at this time, a film thickness monitor commonly used in the prior art can be used to monitor the film thickness of the anti-fingerprint film layer deposited on the product surface;

[0049] S5. When the film thickness monitor curve returns to zero, it means that the anti-fingerprint solution in the solution storage block has completely evaporated. The anti-evaporation module can be controlled to stop heating and the molybdenum boat is left to cool down for about 10 minutes. On the one hand, the temperature is lowered to below the evaporation point of the anti-fingerprint solution to prevent the waste of anti-fingerprint solution. On the other hand, a certain amount of time is given to allow the coated flexible film to be rolled up, and at the same time, the film to be coated is unfolded and moved into the coating room.

[0050] S6. The motor drives the rotating drum 10 of the driving mechanism to rotate, and the anti-fingerprint solution belt 30 drives the reeling roller 22 and the unwinding roller 21 to rotate simultaneously. The anti-fingerprint solution belt 30 passes through the tension roller (conventional technology, not shown in the figure) and is transferred to the reeling roller 22 for reeling; at the same time, the anti-fingerprint solution belt 30 moves forward and just moves the next solution storage block 32 to the molybdenum boat. At this time, it can be confirmed through the observation window that the position of the solution storage block 32 is accurately located in the molybdenum boat of the anti-evaporation module 40; a sensor can also be set for automatic and accurate control. The rotating drum rotates the same arc each time, so that the anti-fingerprint solution belt 30 moves forward at equal intervals, allowing the solution storage blocks 32 to be placed on the molybdenum boat one by one;

[0051] S7, the next blank flexible film sample to be plated is moved into the coating chamber, and the steam resistance module is turned on for heating again;

[0052] S8. Repeat steps S4 to S7 until the continuous coating of the flexible film is completed.

[0053] Comparative Example 1

[0054] A conventional coating process of anti-fingerprint film layer in the prior art:

[0055] Step 1, open the vacuum chamber door and fix the sample on the sample holder;

[0056] Step 2, open the vacuum sealed package of the anti-fingerprint pill, place the pill with the whole surface facing up in the corresponding card slot of the molybdenum boat, and close the door;

[0057] Step 3: Start the vacuuming process and vacuum to 8×10 -3 Pa, turn on the ion source and clean the sample surface for 300 s;

[0058] Step 4: Continue to vacuum until 5×10 -3 Pa, turn on the heating and steam resistance to heat the anti-fingerprint pills, so that the anti-fingerprint solution in them evaporates to the sample surface to form an anti-fingerprint film layer. Monitor the AF film thickness according to the crystal oscillator, and stop heating when the preset film thickness is reached;

[0059] Step 5, turn on the deflation mode, open the hatch, and take out the plated samples.

[0060] Step 6: Repeat steps 1-5 to complete the coating of multi-furnace anti-fingerprint products.

[0061] The relevant parameters of the two coating processes of this comparative example and the embodiment of the present invention are shown in Table 1. It can be seen from Table 1 that the continuous coating method of the present invention greatly improves the coating efficiency. The comparative data of the coating effects of the two coating processes of the comparative example and the embodiment of the present invention are shown in Table 2. It can be seen from Table 2 that after SW-1500 rounds of experiments, the performance of the samples obtained by the coating method of the present invention is more stable and reliable. The practical comparison of different coating methods is shown in Table 3.

[0062] Table 1

[0063]

[0064] Table 2

[0065]

[0066] Table 3

[0067]

Claims

1. A method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films, characterized in that: The steps include: S1. Open the door of the vacuum coating equipment and place the rolled anti-fingerprint solution tape (30) on the unwinding roller (21) of the unwinding mechanism (20); S2, pull out the blank mesh stainless steel conveyor belt (31) at the front end of the anti-fingerprint solution belt (30) from the unwinding roller (21) and flatten it, pass it through the two ends of the steam-proof module (40) also fixed in the furnace, and mesh with the rotating drum (10) of the driving mechanism, and then use a fixing rod to fix the front end of the anti-fingerprint solution belt (30) on the winding roller (22), and then place the first solution storage block (33) on the mesh stainless steel conveyor belt (31) just in the molybdenum boat of the steam-proof module (40); S3. Place the flexible film product to be plated, close the hatch, and start vacuuming. The vacuum degree reaches 5×10 -3 Pa; S4, the resistance wire in the anti-evaporation module (40) is heated, and the anti-fingerprint solution in the solution storage block (32) above it reaches the evaporation point, vaporizes and moves, and adheres to the surface of the flexible film product to be plated; at this time, the film thickness monitor monitors the film thickness of the anti-fingerprint film layer deposited on the product surface; S5. When the curve of the film thickness monitor returns to zero, it means that the anti-fingerprint solution in the solution storage block has evaporated completely. The heating of the anti-evaporation module can be stopped, and the molybdenum boat can be left to cool down to below the evaporation point of the anti-fingerprint solution. S6, the motor drives the rotating drum (10) to rotate, driving the winding roller (22) and the unwinding roller (21) to rotate simultaneously, and the coated flexible film product passes through the tension roller and is transferred to the winding roller (22) for winding up; at the same time, the anti-fingerprint solution belt (30) moves forward, just moving the next solution storage block (32) into the molybdenum boat; each time the rotating drum rotates the same arc, the anti-fingerprint solution belt (30) moves forward at equal intervals; S7, the next blank flexible film sample to be plated is moved into the coating chamber, and the steam resistance module is turned on for heating again; S8. Repeat steps S4 to S7 until the continuous coating of the flexible film is completed.

2. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 1, characterized in that: In step S5, the step is left to stand for 10 minutes; In step S7, the position of the medicine storage block (32) is confirmed through the observation window to be accurately located in the molybdenum boat of the steam resistance module (40).

3. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 1 or 2, characterized in that: A continuous evaporation device is provided in the vacuum coating equipment, including: A driving mechanism, the driving mechanism comprising a motor and a rotating drum (10) driven by the motor, wherein the surface of the rotating drum is serrated; The unwinding and rewinding mechanism (20) comprises an unwinding roller (21), a rewinding roller (22), and a tension roller; The anti-fingerprint liquid belt (30) is mainly a mesh-shaped stainless steel conveyor belt (31), one end of which is wound on the unwinding roller (21) and the other end is wound on the winding roller (22), and passes through a tension roller in the middle, and the mesh on the mesh-shaped stainless steel conveyor belt (31) can be meshed with the saw teeth of the rotating drum (10); a plurality of liquid storage blocks (32) are evenly installed on the mesh-shaped stainless steel conveyor belt (31); An anti-evaporation module (40) comprising a resistance wire and a heating molybdenum boat adapted to the medicine storage block (32); A fixed bracket, used to fix the motor, the drum, the unwinding roller, the winding roller, the tension roller and the steam-proof module; The control module has a control panel arranged outside the vacuum chamber and is electrically connected to the motor and the resistance wire to control their switching.

4. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 3, characterized in that: A connecting ring or nut is welded on the mesh-shaped stainless steel conveyor belt (31); the medicine storage block (32) is square and has through holes at four corners, through which screws (33) or fixing pins or iron wires or steel wires pass to connect with the connecting ring or nut on the mesh-shaped stainless steel conveyor belt (31).

5. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 4, characterized in that: The medicine storage block (32) is 1-2 mm wider than the two sides of the grid-shaped stainless steel conveyor belt (31).

6. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 5, characterized in that: The interval between two adjacent medicine storage blocks (32) on the grid-shaped stainless steel conveyor belt (31) is 50 mm.

7. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 3, characterized in that: The liquid medicine storage block (32) is a stainless steel micro-wire felt dripped with anti-fingerprint liquid medicine.

8. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to claim 3, characterized in that: The size of the medicine storage block (32) is 50 mm×50 mm×2 mm.

9. The method for continuous evaporation of anti-fingerprint solution suitable for continuous coating of flexible films according to any one of claims 3 to 7, characterized in that: The molybdenum boat is a flat molybdenum boat with 3mm limits on both sides, and its two ends are open, accommodating the medicine storage block (32) which is limited within the two sides of the molybdenum boat and can pass through the two ends of the molybdenum boat.

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