OLED inkjet printing substrate vacuum high temperature baking equipment and baking method

Abstract

The present invention relates to the technical field of display panel manufacturing, and discloses a vacuum high-temperature baking device for an OLED inkjet printing substrate and a baking method thereof. The vacuum high-temperature baking device comprises: a vacuum chamber, the vacuum chamber is provided with a closable product inlet and outlet; a vacuum mechanism, the vacuum mechanism is used to form a vacuum environment in the vacuum chamber; a heating plate, the heating plate is located in the vacuum chamber; a heat enclosure, the heat enclosure is installed around the heating plate, and together with the heating plate, forms a box-type structure open upward. The present invention can reduce the heat loss of the heating plate, which is conducive to improving the temperature uniformity of the heating plate.

Description

Technical Field

[0001] The present invention relates to the technical field of display panel manufacturing, and in particular to vacuum high-temperature baking equipment and a baking method for an OLED inkjet printing substrate. Background Art

[0002] Inkjet printing is a key technology in the field of OLED (Organic Light Emitting Diode) display panel manufacturing. After the OLED inkjet printed substrate is dried in a low-temperature vacuum to form a film, it also needs to be baked at a high temperature to remove the high-boiling point solvent in the ink to ensure that the substrate after inkjet printing is completely cured to form a film.

[0003] At present, high-temperature baking after OLED inkjet printing is carried out in the atmosphere or nitrogen. The presence of gas molecules causes the heating plate in the baking equipment to dissipate heat quickly, and the heating efficiency is not high. At the same time, the heating plate also has the problem of poor temperature uniformity. Its edge dissipates heat faster, making the temperature in the middle of the heating plate high and the temperature at the edge low. This situation causes the glass substrate to have a high temperature in the middle and a low temperature at the edge when baking the inkjet printed substrate at high temperature, resulting in uneven temperature of the glass substrate, and finally uneven film thickness of the inkjet printed substrate, affecting product quality. Therefore, the problem of temperature uniformity of the heating plate needs to be improved urgently. Summary of the invention

[0004] The present invention aims to improve at least one technical problem in the background technology.

[0005] In a first aspect, the present invention provides a vacuum baking device, comprising:

[0006] A vacuum chamber, wherein the vacuum chamber is provided with a closable product inlet and outlet;

[0007] A vacuum mechanism, the vacuum mechanism is used to form a vacuum environment in the vacuum chamber to reduce heat loss during baking;

[0008] A heating plate, wherein the heating plate is located in the vacuum chamber;

[0009] A heat enclosure is installed around the heating plate and together with the heating plate forms a box-like structure open upwards. A heating body is arranged inside the heat enclosure.

[0010] The beneficial effect of a vacuum baking device according to the first aspect of the present invention is as follows: a vacuum environment is formed in the vacuum chamber of the device, and a heat enclosure is installed around the heating plate. A heating body is also provided in the heat enclosure, which can compensate for the heat loss of the heating plate during the baking process and improve the temperature uniformity of the heating plate.

[0011] Furthermore, the vacuum baking equipment also includes a carrying platform and a supporting column, both of which are located in the vacuum chamber, and the carrying platform supports the heating plate through the supporting column, so that the carrying platform and the heating plate do not fit each other.

[0012] By adopting the above technical solution, the direct contact between the heating plate and the carrying platform can be reduced, thereby reducing the direct conduction of heat from the heating plate to the carrying platform.

[0013] Furthermore, the vacuum baking equipment also includes a lifting module, which drives the carrying platform to rise or fall. When the carrying platform rises to the upper surface of the heat wall and contacts the lower surface of the upper wall of the vacuum chamber, a closed space is formed between the upper wall of the vacuum chamber, the heat wall and the heating plate.

[0014] By adopting the above technical solution, after the carrying platform is raised, the heat can be gathered in the enclosed space formed, further reducing the heat loss around the heating plate.

[0015] Furthermore, the lifting module includes a first guide rail, a first slider, a second guide rail, a second slider, a driving motor, a first gear set, a second gear set and a transmission shaft. The first guide rail and the second guide rail are respectively located on the left and right sides of the product inlet and outlet opening direction. The first guide rail and the second guide rail are both fixed to the vacuum chamber. Racks are provided on the first guide rail and the second guide rail. The driving motor drives the first slider to slide along the first guide rail through the first gear set. The first gear set and the second gear set are connected by a transmission shaft, and the second slider is driven to slide along the second guide rail through the second gear set.

[0016] By adopting the above technical solution, it can be ensured that when the driving motor is driven, the first slider and the second slider rise or fall synchronously.

[0017] Furthermore, a base plate is connected between the bottom of the first slider and the second slider, and vertical guide rods extending upward are provided on both sides of the base plate. Bellows are provided on the vertical guide rods, and support members are sleeved on the bellows. The bearing platform is installed on the support members.

[0018] By adopting the above technical solutions, the bellows has the advantages of high strength, corrosion resistance, and resistance to temperature changes. It has a certain elasticity while bearing pressure, which can make the lifting and lowering of the carrying platform more stable.

[0019] Furthermore, the vacuum mechanism includes a first vacuum pump and a second vacuum pump, both of which are connected to the vacuum chamber through a vacuum pipe. The first vacuum pump is used to form a vacuum environment in the vacuum chamber, and the second vacuum pump is used to extract the volatile solvent generated in the vacuum chamber during the baking process.

[0020] By adopting the above technical solution, the toxic ink solvent volatilized during high-temperature baking of the OLED substrate can be collected, and the collected toxic gas is subsequently processed so that the toxic gas generated by the equipment does not affect the surrounding equipment environment and personnel.

[0021] Furthermore, the number of the vacuum chambers is more than two, and the vacuum chambers are all connected to a vacuum mechanism.

[0022] By adopting the above technical solution, the equipment can bake multiple OLED substrates at the same time, thereby improving work efficiency.

[0023] In a second aspect, the present invention provides a baking method of a vacuum baking device, comprising the following steps:

[0024] The OLED substrate is placed on a heating plate in a vacuum chamber, wherein a heat enclosure is installed in the vacuum chamber, the heat enclosure surrounds the heating plate, the heat enclosure is located above the heating plate, and a heating body is arranged in the heat enclosure;

[0025] The vacuum chamber is evacuated after forming a sealed space;

[0026] After the vacuum chamber is evacuated to form a vacuum environment, the heating plate starts to heat up, the heating body in the heat enclosure heats up, and vacuum baking begins to heat the OLED substrate to a specified temperature;

[0027] After baking is completed, the vacuum chamber returns to normal pressure.

[0028] The second aspect of the present invention provides a beneficial technical effect of a baking method for a vacuum baking device: by adopting a vacuum baking method, the heat conduction generated by the heating plate can be reduced, and at the same time, a heat fence is set around the heating plate, which can reduce heat loss around the heating plate and improve the temperature uniformity of the heating plate.

[0029] Furthermore, after the OLED substrate is heated to a specified temperature, the heating plate and the heat enclosure are raised so that the top side of the heat enclosure contacts the inner wall of the vacuum chamber, and a closed space is formed to keep the OLED substrate warm, and then the baking is completed.

[0030] By adopting the above technical solution, the enclosed space formed by the rising heating plate and the heat wall can gather heat, which can further reduce the heat loss of the heating plate.

[0031] Furthermore, after the OLED substrate is completely insulated, the solvent is evacuated from the vacuum chamber.

[0032] By adopting the above technical solution, harmful gases generated during the baking process are extracted and subsequently treated, thereby preventing the baking method from polluting the surrounding environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 It is an axonometric diagram of a vacuum high temperature baking device for an OLED inkjet printing substrate of the present invention;

[0035] Figure 2 This is a front view of a single vacuum chamber and vacuum mechanism of a vacuum high temperature baking device for an OLED inkjet printed substrate of the present invention;

[0036] Figure 3 This is a cross-sectional view of a single vacuum chamber of a vacuum high-temperature baking device for an OLED inkjet printed substrate of the present invention;

[0037] Figure 4 It is a front view of the lifting module of the present invention;

[0038] Figure 5 The present invention is a flow chart of a baking method of a vacuum baking device.

[0039] In the attached drawings: 1-vacuum chamber; 11-product inlet and outlet; 12-gate valve; 13-upper wall of vacuum chamber; 2-vacuum mechanism; 21-first vacuum pump; 22-second vacuum pump; 23-vacuum pipe; 3-heating plate; 4-heat enclosure; 5-bearing platform; 6-support column; 7-lifting module; 711-first guide rail; 712-first slider; 721-second guide rail; 722-second slider; 73-drive motor; 741-first gear set; 742-second gear set; 75-transmission shaft; 76-bottom plate; 77-vertical guide rod; 78-bellows; 79-support member. DETAILED DESCRIPTION

[0040] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0041] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element 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.

[0042] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0043] Combine the following Figures 1 to 5 Embodiments of the present invention are described.

[0044] This embodiment relates to a vacuum high temperature baking device for an OLED inkjet printed substrate and a baking method thereof. Currently, the heating plate in the OLED inkjet printed substrate baking device has a fast heat dissipation speed and poor temperature uniformity. This embodiment reduces the heat loss around the heating plate and improves the temperature uniformity of the heating plate.

[0045] Reference Figures 1 to 3 The vacuum baking equipment of this embodiment comprises:

[0046] A vacuum chamber 1, wherein the vacuum chamber 1 is provided with a closable product inlet and outlet 11, and a gate valve 12 which can be opened or closed automatically is installed on the product inlet and outlet, and the material can be automatically fed and discharged by a robot without manual operation;

[0047] A vacuum mechanism 2, the vacuum mechanism 2 is used to form a vacuum environment in the vacuum chamber;

[0048] A heating plate 3, wherein the heating plate 3 is located in the vacuum chamber 1;

[0049] The heat enclosure 4 is installed around the heating plate 3 and together with the heating plate 3 forms an upwardly open box structure. A heating body (not shown in the figure) is arranged in the heat enclosure 4. During the heating process of the heating plate 3, the heating body in the heat enclosure 4 is heated synchronously, which makes up for the heat loss around the heating plate and improves the temperature uniformity of the heating plate.

[0050] Furthermore, the vacuum baking equipment in this embodiment also includes a carrying platform 5 and a support column 6, and the carrying platform 5 and the support column 6 are both located in the vacuum chamber 1. The carrying platform 5 supports the heating plate 3 through the support column 6, so that the carrying platform 5 and the heating plate 3 are not in contact with each other, thereby reducing the direct contact between the heating plate 3 and the carrying platform 5, thereby reducing the heat of the heating plate 3 directly transferred to the carrying platform 5.

[0051] Reference Figure 3 In this embodiment, the vacuum baking equipment further includes a lifting module 7, which drives the carrying platform 5 to rise or fall. When the carrying platform 5 rises to the point where the upper surface of the heat enclosure 4 contacts the lower surface of the upper wall 13 of the vacuum chamber, a closed space is formed between the upper wall 13 of the vacuum chamber, the heat enclosure 4 and the heating plate 3. After the heating plate 3 is heated, the heat is gathered in this closed space, further reducing the heat loss from the heating plate to the surrounding area.

[0052] Reference Figure 4 In this embodiment, the lifting module 7 includes a first guide rail 711, a first slider 712, a second guide rail 721, a second slider 722, a driving motor 73, a first gear set 741, a second gear set 742 and a transmission shaft 75. The first guide rail 711 and the second guide rail 721 are respectively located on the left and right sides of the opening direction of the product inlet and outlet 11. The first guide rail 711 and the second guide rail 721 are both fixed to the vacuum chamber 1. The first guide rail 711 and the second guide rail 721 are both provided with racks (not shown in the figure). The driving motor 73 drives the first slider 712 to slide along the first guide rail 711 through the first gear set 741. The first gear set 741 and the second gear set 742 are connected by transmission through the transmission shaft 75. The second gear group drives the second slider 722 to slide along the second guide rail 721; in the present embodiment, the first slider 712 and the second slider 722 are both fixedly connected by the base plate 76, and the first gear group 741 and the second gear group 742 are both installed on the base plate 76. When the lifting module 7 is in operation, the driving motor 73 drives the first gear group 741 to rotate. The rotation of the first gear group 741 divides the input rotation into two output rotations. The first gear group 741 drives the first slider 712 to rise or fall. At the same time, the first gear group 741 drives the second gear group 742 to rotate through the transmission shaft 75, and the second gear group 742 drives the second slider 722 to rise or fall, thereby realizing the synchronous rise or fall of the first slider 712 and the second slider 722.

[0053] Furthermore, in the present embodiment, a base plate 76 is connected between the bottom of the first slider 712 and the bottom of the second slider 722. Vertical guide rods 77 extending upward are provided on both sides of the base plate 76. Bellows 78 are provided on the vertical guide rods 77. Support members 79 are sleeved on the bellows 78. The supporting platform 5 is installed on the support members 79. The bellows 78 has the advantages of high strength, corrosion resistance, and temperature resistance. It has a certain elasticity while bearing pressure. In the present embodiment, the lifting module 7 introduces the bellows 78 for carrying the supporting platform 5, which can make the supporting platform 5 more stable during the rising or falling process.

[0054] Reference Figure 1 In this embodiment, the vacuum mechanism 2 includes a first vacuum pump 21 and a second vacuum pump 22. The first vacuum pump 21 and the second vacuum pump 22 are both connected to the vacuum chamber 1 through a vacuum pipe 23. The first vacuum pump 21 is used to form a vacuum environment in the vacuum chamber 1. The second vacuum pump 22 is used to extract the volatile solvent generated in the vacuum chamber during the baking process. The extracted toxic gas is collected and processed to prevent the toxic gas generated by the vacuum baking equipment during the baking process of the OLED substrate from polluting the surrounding environment.

[0055] Reference Figure 1In this embodiment, the vacuum baking device has two vacuum chambers 1, both of which are connected to the vacuum mechanism 2, so that the vacuum baking device in this embodiment can bake two OLED substrates at the same time, thereby improving work efficiency.

[0056] Reference Figure 5 The baking method of the vacuum baking equipment of this embodiment comprises the following steps:

[0057] The OLED substrate is placed on the heating plate 3 of the vacuum chamber 1. A heat enclosure 4 is installed in the vacuum chamber 1. The heat enclosure 4 is arranged around the heating plate 3. The heat enclosure 4 is located above the heating plate 3. A heating body is arranged in the heat enclosure 4.

[0058] The vacuum chamber 1 is evacuated after forming a sealed space;

[0059] After the vacuum chamber 1 is evacuated to form a vacuum environment, the heating plate 3 starts to heat, the heating body in the heat enclosure 4 heats up, and vacuum baking starts to raise the temperature of the OLED substrate to a specified temperature;

[0060] After baking is completed, the vacuum chamber 1 returns to normal pressure.

[0061] In the above baking method, a vacuum environment is formed in the vacuum chamber 1, which reduces the heat conduction generated by the heating plate 3, and the heat enclosure 4 is arranged around the heating plate 3 to reduce the heat loss around the heating plate 3.

[0062] Furthermore, after the OLED substrate is heated to a specified temperature, the heating plate 3 and the heat enclosure 4 are lifted by the lifting module 7 so that the top side of the heat enclosure 4 contacts the lower surface of the upper wall 13 of the vacuum chamber, and a closed space is formed. After the OLED substrate is kept warm, baking is completed.

[0063] In the above baking method, the enclosed space formed by the rising heating plate 3 and the heat enclosure 4 can gather heat, so the OLED substrate has double protection during baking. The first layer is the vacuum environment formed in the vacuum chamber 1, which reduces the heat conduction generated by the heating plate 3. The second layer is the enclosed space formed around the heating plate 3, which reduces the heat loss around the heating plate 3 and gathers the heat in this enclosed space, thereby improving the temperature uniformity of the heating plate 3 as a whole.

[0064] Furthermore, after the OLED substrate is kept warm, the second vacuum pump 22 is started to extract the volatilized solvent in the vacuum chamber 1. The extracted toxic gas is collected and transported to a toxic gas treatment station for treatment, without causing pollution to the surrounding environment of the vacuum baking equipment of this embodiment.

[0065] The preferred embodiments of the present invention are described in detail above, but the present disclosure is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present disclosure.

Claims

1. A vacuum baking device, characterized in that: include: A vacuum chamber, wherein the vacuum chamber is provided with a closable product inlet and outlet; A vacuum mechanism, the vacuum mechanism is used to form a vacuum environment in the vacuum chamber; A heating plate, wherein the heating plate is located in the vacuum chamber; A heat enclosure, the heat enclosure is installed around the heating plate and together with the heating plate forms a box-like structure open upward, and a heating body is arranged in the heat enclosure; A bearing platform, the bearing platform is used to support the heating plate; A lifting module drives the carrying platform to rise or fall. When the carrying platform rises to the point where the upper surface of the heat enclosure contacts the lower surface of the upper wall of the vacuum chamber, a closed space is formed between the upper wall of the vacuum chamber, the heat enclosure and the heating plate.

2. The vacuum baking equipment according to claim 1, characterized in that: The vacuum baking equipment further comprises a supporting column, and the carrying platform supports the heating plate via the supporting column, so that the carrying platform and the heating plate do not fit each other.

3. The vacuum baking equipment according to claim 1, characterized in that: The lifting module includes a first guide rail, a first slider, a second guide rail, a second slider, a driving motor, a first gear set, a second gear set and a transmission shaft. The first guide rail and the second guide rail are respectively located on the left and right sides of the product inlet and outlet opening direction. The first guide rail and the second guide rail are both fixed to the vacuum chamber. Racks are provided on the first guide rail and the second guide rail. The driving motor drives the first slider to slide along the first guide rail through the first gear set. The first gear set and the second gear set are connected by a transmission shaft, and the second slider is driven to slide along the second guide rail through the second gear set.

4. The vacuum baking equipment according to claim 3, characterized in that: A bottom plate is connected between the bottoms of the first slider and the second slider, vertical guide rods extending upward are provided on both sides of the bottom plate, bellows are provided on the vertical guide rods, support members are sleeved on the bellows, and the bearing platform is installed on the support members.

5. The vacuum baking equipment according to claim 1, characterized in that: The vacuum mechanism includes a first vacuum pump and a second vacuum pump, both of which are connected to the vacuum chamber through a vacuum pipe. The first vacuum pump is used to form a vacuum environment in the vacuum chamber, and the second vacuum pump is used to extract the volatile solvent generated in the vacuum chamber during the baking process.

6. The vacuum baking equipment according to claim 1, characterized in that: The number of the vacuum chambers is more than two, and the vacuum chambers are all connected to a vacuum mechanism.

7. A baking method for a vacuum baking device, characterized in that: The steps include: The OLED substrate is placed on a heating plate in a vacuum chamber, wherein a heat enclosure is installed in the vacuum chamber, the heat enclosure surrounds the heating plate, the heat enclosure is located above the heating plate, and a heating body is arranged in the heat enclosure; The vacuum chamber is evacuated after forming a sealed space; After the vacuum chamber is evacuated to form a vacuum environment, the heating plate starts to heat up, the heating body in the heat enclosure heats up, and vacuum baking begins to heat the OLED substrate to a specified temperature; Raise the heating plate and the heat enclosure so that the top side of the heat enclosure contacts the inner wall of the vacuum chamber and forms a closed space to keep the OLED substrate warm; After baking is completed, the vacuum chamber returns to normal pressure.

8. The baking method of the vacuum baking equipment according to claim 7, characterized in that: After the OLED substrate is completely insulated, the solvent is evaporated from the vacuum chamber.

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