阅读说明：本技术 一种喷墨打印装置以及制备薄膜的方法 (Ink-jet printing device and method for preparing film ) 是由 孙琳 戴伟杰 吕孝鹏 刘明星 于 2019-09-09 设计创作，主要内容包括：本发明实施例提供了一种喷墨打印装置以及制备薄膜的方法,解决了现有技术中采用喷墨打印技术制备OLED显示屏体中的膜层时,膜层均一性较低从而降低了显示效果的技术问题。本发明实施例提供的一种喷墨打印装置,用于在衬底基板上打印墨滴,形成显示器件中的像素层,所述喷墨打印装置通过在入料口内部设置温度控制装置,用于调节所述墨水经过所述入料口后所述墨水的温度,以使得衬底基板上先打印的区域的墨滴的温度大于后打印的区域的墨滴的温度,因此在使用喷墨打印的方法打印像素层的时候,先打印的墨水和后打印的墨水凝固时间差别较小,从而使得墨水凝固后形成的像素层的厚度较为均匀,提高了像素层的均一性,提高了显示效果。(The embodiment of the invention provides an ink-jet printing device and a method for preparing a film, and solves the technical problem that when an ink-jet printing technology is adopted to prepare a film layer in an OLED display screen body in the prior art, the uniformity of the film layer is low, so that the display effect is reduced. The ink-jet printing device provided by the embodiment of the invention is used for printing ink drops on a substrate to form a pixel layer in a display device, and the temperature control device is arranged in a material inlet of the ink-jet printing device and is used for adjusting the temperature of the ink after the ink passes through the material inlet, so that the temperature of the ink drops in a first printing area on the substrate is higher than that of the ink drops in a second printing area, and therefore, when the pixel layer is printed by using an ink-jet printing method, the solidification time difference between the first printing ink and the second printing ink is smaller, the thickness of the pixel layer formed after the ink is solidified is more uniform, the uniformity of the pixel layer is improved, and the display effect is improved.)

1. An ink jet printing apparatus for printing ink droplets on a substrate to form a pixel layer in a display device, comprising:

The material inlet is used for adding ink for preparing the pixel layer; and the number of the first and second groups,

the temperature control device is arranged in the feeding port and used for adjusting the temperature of the ink after the ink passes through the feeding port, so that the temperature of the ink drop in the area printed firstly on the substrate base plate is higher than that of the ink drop in the area printed later, and the temperature of the ink drop in the area printed later is higher than the solidification temperature of the ink drop.

2. Inkjet printing apparatus according to claim 1 wherein said temperature control means includes a heating resistor for adjusting the temperature of said ink after passing through said inlet port by adjusting the power.

3. Inkjet printing apparatus according to claim 2 wherein said heating resistor is disposed at a bottom of said inlet; and/or the presence of a gas in the gas,

The heating resistor is arranged on the inner wall of the feeding port.

4. Inkjet printing apparatus according to claim 1, further comprising:

One end of the communicating vessel is communicated with the feeding port;

The sprayer is fixed at the other end of the communicating vessel and communicated with the communicating vessel; and the number of the first and second groups,

and the blowing device is arranged on the communicating vessel.

5. Inkjet printing apparatus according to claim 4, further comprising:

and the drying element is fixed on the blowing device.

6. inkjet printing apparatus according to claim 5 wherein the drying element is an annular drying element or a planar drying element.

7. Inkjet printing apparatus according to claim 6,

The area of the drying element is greater than or equal to the area of a single pixel.

8. A method of forming a thin film for forming a pixel layer in a display device, comprising:

The temperature of the ink drops in the area printed firstly on the substrate base plate is higher than that of the ink drops in the area printed later, and the temperature of the ink drops in the area printed later is higher than the solidification temperature of the ink drops.

9. The method of claim 8, wherein causing the temperature of the ink drops in the pre-printed area to be greater than the temperature of the ink drops in the post-printed area on the substrate comprises:

Sequentially printing ink drops on different areas on a substrate;

And when different areas on the substrate are printed, the temperature of the ink drops is sequentially reduced according to the printing sequence of the ink drops, and the temperature of the ink drops in the last printing area is higher than the solidification temperature of the ink drops.

10. The method of claim 8, wherein the difference between the temperature of the ink drops in the first printed area and the temperature of the ink drops in the second printed area is equal to the product of the ink solidification rate and a first time, wherein the first time is the difference between the time an ink drop lands in the second printed area and the time an ink drop lands in the first printed area.

Technical Field

The invention relates to the technical field of display, in particular to an ink-jet printing device and a method for preparing a film.

Background

Ink jet printing is a film forming method in which ink of a functional material is printed at a corresponding position under the precise control of a computer, and a digital pattern is converted into a pattern. In the OLED display industry, inkjet printing technology may be used to print a print area of a substrate to form a target film layer. However, when the film layer in the OLED display screen body is printed by adopting the ink-jet printing technology, the uniformity of the film layer is lower, and the display effect is further reduced.

disclosure of Invention

In view of this, the embodiment of the invention provides an inkjet printing device and a method for preparing a thin film, which solve the technical problem that when an inkjet printing technology is adopted to prepare a film layer in an OLED display screen body in the prior art, the uniformity of the film layer is low, so that the display effect is reduced.

For the purpose of making the objects, technical means and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

according to an aspect of the present invention, an embodiment of the present invention provides an inkjet printing apparatus for printing ink droplets on a substrate to form a pixel layer in a display device, the inkjet printing apparatus including: the material inlet is used for adding ink for preparing the pixel layer; and the temperature control device is arranged inside the feeding port and used for adjusting the temperature of the ink after the ink passes through the feeding port, so that the temperature of the ink drop in the area printed firstly on the substrate base plate is greater than the temperature of the ink drop in the area printed later, and the temperature of the ink drop in the area printed later is greater than the solidification temperature of the ink drop.

In an embodiment of the present invention, the temperature control device includes a heating resistor, and the temperature of the ink after passing through the feeding port is adjusted by adjusting power of the heating resistor.

In an embodiment of the present invention, the heating resistor is disposed at the bottom of the feeding port; and/or the heating resistor is arranged on the inner wall of the feeding port.

in an embodiment of the present invention, the inkjet printing apparatus further includes: one end of the communicating vessel is communicated with the feeding port; the sprayer is fixed at the other end of the communicating vessel and communicated with the communicating vessel; and the blowing device is arranged on the communicating vessel.

In an embodiment of the present invention, the inkjet printing apparatus further includes: and the drying element is fixed on the blowing device.

In an embodiment of the present invention, the drying element is an annular drying element or a planar drying element.

In an embodiment of the invention, an area of the drying element is greater than or equal to an area of a single pixel.

as another aspect of the present invention, an embodiment of the present invention provides a method of manufacturing a thin film for forming a pixel layer in a display device, the method including: the temperature of the ink drops in the area printed firstly on the substrate base plate is higher than that of the ink drops in the area printed later, and the temperature of the ink drops in the area printed later is higher than the solidification temperature of the ink drops.

In an embodiment of the present invention, the making the temperature of the ink droplets in the first printed area on the substrate higher than the temperature of the ink droplets in the second printed area includes: sequentially printing ink drops on different areas on a substrate; and when different areas on the substrate are printed, the temperature of the ink drops is sequentially reduced according to the printing sequence of the ink drops, and the temperature of the ink drops in the last printing area is higher than the solidification temperature of the ink drops.

in one embodiment of the invention, the difference between the temperature of the ink drops in the first printed area and the temperature of the ink drops in the second printed area is equal to the product of the ink solidification speed and a first time, wherein the first time is the difference between the time when the ink drops fall to the second printed area and the time when the ink drops fall to the first printed area.

The ink-jet printing device provided by the embodiment of the invention is used for printing ink drops on a substrate to form a pixel layer in a display device, and the temperature control device is arranged in a material inlet of the ink-jet printing device and is used for adjusting the temperature of the ink after the ink passes through the material inlet, so that the temperature of the ink drops in a first printing area on the substrate is higher than that of the ink drops in a second printing area, and therefore, when the pixel layer is printed by using an ink-jet printing method, the solidification time difference between the first printing ink and the second printing ink is smaller, the thickness of the pixel layer formed after the ink is solidified is more uniform, the uniformity of the pixel layer is improved, and the display effect is improved.

Drawings

FIG. 1 is a schematic structural diagram of an inkjet printing apparatus according to an embodiment of the present invention;

Fig. 2 is a schematic diagram illustrating division of each region in a substrate according to an embodiment of the present invention;

Fig. 3 is a schematic diagram illustrating a specific position of a temperature control device disposed at a feeding port of an inkjet printing apparatus according to an embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating a specific position of a temperature control device disposed at a feeding port of an inkjet printing apparatus according to another embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an inkjet printing apparatus according to another embodiment of the present invention;

Fig. 6 is a schematic structural diagram of an inkjet printing apparatus according to another embodiment of the present invention.

Detailed Description

As described in the background art, the present inventors have found that, in the prior art, when the film layer in the OLED display panel is prepared by using the inkjet printing technology, the uniformity of the film layer is low, and thus the display effect is reduced, and that the problem occurs because the ink printed first solidifies and the ink printed later solidifies during the inkjet printing process, and when the ink printed later begins to solidify, the ink printed first has already solidified. The film layer is easy to be uneven due to the batch solidification, so that the uniformity of the film layer is reduced, and the display effect is reduced; and the ink after printing is sprayed from the ink jet opening to easily cause nozzle blockage.

Based on the above, the invention provides an inkjet printing device, which is used for printing ink drops on a substrate to form a pixel layer in a display device, wherein the inkjet printing device is provided with a temperature control device inside a material inlet and is used for adjusting the temperature of the ink after the ink passes through the material inlet, so that the temperature of the ink drops in a first printing area on the substrate is higher than that of the ink drops in a second printing area, and therefore when the pixel layer is printed by using an inkjet printing method, the first printing ink and the second printing ink are solidified simultaneously, so that the thickness of the pixel layer formed after the ink is solidified is relatively uniform, the uniformity of the pixel layer is improved, and the display effect is improved.

Specifically, the present invention provides an inkjet printing apparatus for printing ink droplets on a substrate to form a pixel layer in a display device, the inkjet printing apparatus including: the material inlet is used for adding ink for preparing the pixel layer; and the temperature control device is fixed in the feeding port and used for adjusting the temperature of the ink after the ink passes through the feeding port, so that the temperature of the ink drop in the area printed firstly on the substrate base plate is higher than that of the ink drop in the area printed later, and the temperature of the ink drop in the area printed later is higher than the solidification temperature of the ink drop.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 shows an inkjet printing apparatus according to an embodiment of the present invention, for printing ink droplets on a substrate to form a pixel layer in a display device, as shown in fig. 1, the inkjet printing apparatus includes: a feeding port 1 for adding ink for preparing a pixel layer; a communicating vessel 3 with one end communicated with the feeding port 1; a nozzle 4 fixed at the other end of the communicating vessel 3 and communicated with the communicating vessel 3; and the temperature control device 2 is fixed in the feeding port 1 and used for adjusting the temperature of the ink after the ink passes through the feeding port 1, so that the temperature of the ink drops in the area printed firstly on the substrate base plate is higher than that of the ink drops in the area printed secondly, and the temperature of the ink drops in the area printed secondly is higher than the solidification temperature of the ink drops.

the printing sequence of the regions on the base substrate 10 is shown in fig. 2, the base substrate 10 is divided into four regions, i.e., a region a, a region B, a region C, and a region D, and the printing sequence is a region a, a region B, a region C, and a region D. The temperature control device 2 adjusts the temperature to T1 when the a region on the base substrate 10 is printed by the inkjet printing device, the temperature control device 2 adjusts the temperature to T2 when the B region on the base substrate is printed by the inkjet printing device, the temperature control device 2 adjusts the temperature to T3 when the C region on the base substrate is printed by the inkjet printing device, and the temperature control device 2 adjusts the temperature to T4 when the D region on the base substrate is printed by the inkjet printing device. T1 is greater than T2 is greater than T3 is greater than T4 is greater than T0(T0 is the solidification temperature of ink drops), so that the time difference of starting solidification of the ink drops printed on the substrate 10 in the area A, the area B, the area C and the area D is smaller, the thickness of a pixel layer formed after ink solidification is uniform, the uniformity of the pixel layer is improved, and the display effect is improved.

In one embodiment of the invention, the temperature adjustment device adjusts the temperature between the ink droplets of the first print area and the ink droplets of the second print area such that the difference between the temperature of the ink droplets of the first print area and the temperature of the ink droplets of the second print area is equal to the product of the solidification rate of the ink and a first time, wherein the first time is the difference between the time when the ink droplets land on the second print area and the time when the ink droplets land on the first print area. For example, the time point when the ink droplet lands on the a region is T1, the time point when the ink droplet lands on the B region is T2, T1-T2 (T2-T1) × V, where V is the solidification speed of the ink, and T1-T2 is the difference between the temperature of the ink droplet in the first printed region and the temperature of the ink droplet in the second printed region. Therefore, the time for the ink dropped to the area A and the time for the ink dropped to the area B to start to solidify are the same (namely, the ink begins to solidify at the same time), the thickness of a pixel layer formed after the ink solidifies is further more uniform, the uniformity of the pixel layer is further improved, and the display effect is improved.

In an embodiment of the present invention, the temperature control device 2 includes a heating resistor, and the temperature of the ink after passing through the inlet 1 is adjusted by adjusting the power of the heating resistor.

In a further embodiment of the invention, the power of the heating resistor is such that: CM Δ T ═ P Δ T, where M represents the mass of ink solute or solvent required for one batch printing; c represents the specific heat capacity of the ink solute or solvent; p represents the power of the resistor; Δ T: representing the temperature difference of two adjacent batches of printing ink; Δ t: which represents the difference between the time at which an ink droplet lands on the first print area and the time at which an ink droplet lands on the second print area.

It should be understood that the manner of adjusting the temperature of the temperature control device 2 may be selected according to the actual application scenario, and may be the heating resistor as described above, or may be other devices for adjusting the temperature, so long as the temperature of the ink after passing through the inlet 1 can be controlled, and the specific temperature control manner of the temperature control device 2 is not limited in the embodiment of the present invention.

In an embodiment of the present invention, when the heating resistor is fixed inside the material inlet 1, the specific position of the heating resistor can be as follows: as shown in fig. 3, the heating resistor is fixed at the bottom of the feeding port 1, and when the ink passes through the bottom of the feeding port, the heating resistor can heat the ink, so as to adjust the temperature of the ink after passing through the feeding port 1.

in another embodiment of the present invention, when the heating resistor is fixed inside the material inlet 1, the specific position of the heating resistor may be as follows: as shown in fig. 4, the heating resistor is fixed on the inner wall of the feeding port, and when the ink passes through the feeding port 1, the ink can be heated, so as to adjust the temperature of the ink after passing through the feeding port 1. Preferably, when the heating resistors are fixed on the inner wall of the feeding port 1, the heating resistors can be a plurality of heating resistors and the plurality of heating resistors are uniformly distributed.

it should be understood that the specific position of the heating resistor fixed on the inner wall of the material inlet 1 may be selected according to the actual application scenario, so long as the heating resistor can adjust the temperature of the ink after passing through the material inlet 1, and the embodiment of the present invention does not limit the specific position of the heating resistor fixed on the inner wall of the material inlet 1.

In an embodiment of the present invention, as shown in fig. 5, the ink for inkjet printing includes ink and solvent, and in order to better distinguish the ink from the solvent, the feeding port 1 in the inkjet printing apparatus includes a first feeding port 11 and a second feeding port 12, wherein the first feeding port 11 is used for adding the ink for preparing the pixel layer, and the second feeding port 12 is used for adding the solvent for preparing the pixel layer, so that a first temperature control device 21 is fixed inside the first feeding port 11, a second temperature control device 22 is fixed inside the second feeding port 12, the ink and the solvent after passing through the second feeding port 12 are mixed together to form ink, and then the ink enters the nozzle 4 through the communicating device 3, and then is ejected onto the substrate through the nozzle 4.

It should be understood that the heating manner of the first temperature control device 21 and the second temperature control device 22 and the position of the first temperature control device 21 disposed at the first feeding port 11 and the position of the second temperature control device 22 disposed at the second feeding port 12 can be set according to practical applications, for example, the first temperature control device 21 and the second temperature control device 22 are both heating resistors, and the first temperature control device 21 is fixed at the bottom of the first feeding port 11 and the second temperature control device 22 is fixed at the inner wall of the second feeding port 12. Therefore, the heating method of the first temperature control device 21 and the second temperature control device 22, the position where the first temperature control device 21 is disposed at the first inlet 11, and the position where the second temperature control device 22 is disposed at the second inlet 12 are not limited in the embodiment of the present invention.

In an embodiment of the present invention, as shown in fig. 6, the inkjet printing apparatus further includes a communicating vessel 3 communicating with the feeding port 1 and a blowing device 5 connected to the communicating vessel 3, when the ink of one pixel is sprayed on the substrate 10, the blowing device 5 can accelerate the flow of the ink, improve the surface flatness of the ink, enable the upper surface of the ink to be blown flat, and increase the uniformity of the film.

In a further embodiment of the present invention, the blowing device 5 is movably connected to the communicating vessel 3, that is, the blowing device 5 is movable relative to the communicating vessel 3, when the ink of a pixel is coated on the substrate, the blowing device 5 is moved to the center of the pixel layer, that is, the center of the blowing device 5 is aligned with the center of the pixel up and down, the air blown by the blowing device 5 blows the ink at the center of the pixel to the periphery, so as to accelerate the ink at the center of the pixel to flow to the periphery until the upper surface of the ink is blown flat, further increasing the uniformity of the film layer, and improving the display effect.

In another embodiment of the present invention, as shown in fig. 6, the inkjet printing apparatus further includes a drying member 6 connected to the blowing device 5. When the ink of a pixel is sprayed on the substrate, the drying element 6 can accelerate the volatilization of the solvent in the ink and accelerate the solidification of the ink. Preferably, the drying element 6 is a UV lamp.

In a further embodiment of the present invention, the drying element 6 is movably connected to the communicating vessel 3, that is, the drying element 6 is movable relative to the communicating vessel 3, when the ink of one pixel is sprayed on the substrate, the drying element 6 is moved to the center of the pixel layer, that is, the center of the drying element 6 is aligned with the center of the pixel up and down, and the drying element 6 can accelerate the volatilization of the solvent in the ink, and accelerate the solidification of the ink at each position of the pixel.

In a further embodiment of the invention, the drying element 6 is a circular drying element 6 or a flat drying element 6.

Preferably, the area of the drying element 6 is greater than or equal to the area of a single pixel. The ink drying device can dry ink at each position on a pixel point, and the uniformity of a pixel layer is improved.

the embodiment of the invention also provides a preparation method of the film, which is used for forming a pixel layer in a display device and comprises the following steps: so that the temperature of the ink droplets in the first printed area on the substrate base plate is greater than the temperature of the ink droplets in the second printed area. Therefore, when the pixel layer is printed by using the ink-jet printing method, the ink printed firstly and the ink printed later are solidified simultaneously, so that the thickness of the pixel layer formed after the ink is solidified is uniform, the uniformity of the pixel layer is improved, and the display effect is improved.

in an embodiment of the present invention, making the temperature of the ink droplets of the first printed area on the substrate higher than the temperature of the ink droplets of the second printed area comprises:

sequentially printing ink drops on different areas on a substrate; and

And when different areas on the substrate are printed, the temperature of the ink drops is sequentially reduced according to the printing sequence of the ink drops. For example, when the printing order of the respective areas on the base substrate is as shown in fig. 2, the base substrate is divided into four areas, which are an a area, a B area, a C area, and a D area, respectively, and the printing order is the a area, the B area, the C area, and the D area. The temperature control device adjusts the temperature to T1 when the a region on the base substrate is printed using the inkjet printing device, T2 when the B region on the base substrate is printed using the inkjet printing device, T3 when the C region on the base substrate is printed using the inkjet printing device, and T4 when the D region on the base substrate is printed using the inkjet printing device. T1 is greater than T2 is greater than T3 is greater than T4 is greater than T0(T0 is the solidification temperature of ink drops), so that the time difference of the beginning solidification of the ink drops printed on the substrate in the area A, the area B, the area C and the area D is smaller, the thickness of a pixel layer formed after the ink is solidified is more uniform, the uniformity of the pixel layer is improved, and the display effect is improved.

In a further embodiment of the invention, the difference between the temperature of the ink drops in the first printed area and the temperature of the ink drops in the second printed area is equal to the product of the ink solidification rate and a first time, wherein the first time is the difference between the time the ink drops fall into the second printed area and the time the ink drops fall into the first printed area. For example, the time point when the ink droplet lands on the a region is T1, the time point when the ink droplet lands on the B region is T2, T1-T2 (T2-T1) × V, where V is the solidification speed of the ink, and T1-T2 is the difference between the temperature of the ink droplet in the first printed region and the temperature of the ink droplet in the second printed region. Therefore, the time for the ink dropped to the area A and the time for the ink dropped to the area B to start to solidify are the same (namely, the ink begins to solidify at the same time), the thickness of a pixel layer formed after the ink solidifies is further more uniform, the uniformity of the pixel layer is further improved, and the display effect is improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the invention, so that any modifications, equivalents and the like included in the spirit and principle of the present invention should be included in the scope of the present invention.