Colloidal quantum dot high-throughput inkjet printing device, printing method and applications

Abstract

This disclosure provides a high-throughput inkjet printing device, printing method, and application for colloidal quantum dots. The inkjet printing device includes: a liquid supply unit comprising a pneumatic pump (1) and multiple liquid storage bottles (2), wherein the colloidal quantum dot inks contained in the multiple liquid storage bottles (2) are different; the pneumatic pump (1) is used to control the colloidal quantum dot inks to enter the inkjet printhead through the liquid inlet pipe (3); a high-throughput inkjet printhead comprising multiple independent microfluidic channels (4) and nozzles (5), each microfluidic channel (4) being connected to a corresponding liquid inlet pipe (3), and the cross-sectional area of ​​the microfluidic channel (4) gradually decreasing from the inlet end to the outlet end; the nozzle (5) having a hollow needle-shaped tip, with the tip facing the substrate to be printed, and different colloidal quantum dot inks dripping onto different positions on the substrate through the nozzle (5). The printing device of this disclosure can print multiple different colloidal quantum dot inks simultaneously, improving printing efficiency, and the ink material has good uniformity and stability.

Description

Technical Field

[0001] This disclosure relates to the field of inkjet printing technology, specifically to a colloidal quantum dot high-throughput inkjet printing device, printing method, and application. Background Technology

[0002] Inkjet printing, with its variable data, large-format production capability, ease of operation, and patterning ability, has become a new choice for the further processing and preparation of many functional materials. As more and more high-performance functional materials are developed, they are patterned in the form of functional inks with the help of inkjet printing technology, and are widely used in optoelectronic sensors and displays. Colloidal quantum dot materials refer to semiconductor nanocrystals with diameters of 2-20 nanometers, possessing tunable band gaps and functionalizable characteristics. By adjusting the size and composition of the material, the absorption spectrum wavelength of colloidal quantum dots can be controlled. Applying colloidal quantum dot materials to inkjet ink systems combines the excellent optoelectronic properties of quantum dot materials with the controllability of inkjet printing technology, which is beneficial to maximizing the working efficiency of quantum dot optoelectronic devices. However, traditional inkjet printing systems can only print one type of colloidal quantum dot ink at a time, which severely limits its application in applications requiring the simultaneous printing of different types of colloidal quantum dots. For example, in the case of colloidal quantum dot-based spectral chips, hundreds or thousands of different colloidal quantum dots need to be printed on a single receiving circuit surface, and current technologies result in extremely low printing efficiency. Summary of the Invention

[0003] In view of the above, the first aspect of this disclosure provides a colloidal quantum dot high-throughput inkjet printing apparatus, comprising: a liquid supply unit including a pneumatic pump and multiple liquid storage bottles, wherein the multiple liquid storage bottles contain different colloidal quantum dot inks, and the pneumatic pump is used to control the colloidal quantum dot inks to enter the inkjet printhead through the liquid inlet pipe; a high-throughput inkjet printhead including multiple independent microfluidic channels and nozzles, each microfluidic channel being connected to a corresponding liquid inlet pipe, the cross-sectional area of ​​the microfluidic channel gradually decreasing from the inlet end to the outlet end; and a nozzle having a hollow needle-shaped tip, the tip facing the substrate to be printed, and different colloidal quantum dot inks dripping from the nozzle to different positions on the substrate.

[0004] According to embodiments of this disclosure, multiple microfluidic channels are arranged in an array, with an array size of 2×2 to 100×100 and an array period of 0.2 to 2 mm; the diameter of the inlet end cross-section of each microfluidic channel is 0.1 to 1 mm.

[0005] According to embodiments of this disclosure, the inner diameter of the needle tip of the nozzle is 10~100μm, and the period is 20~200μm.

[0006] According to embodiments of this disclosure, the nozzle undergoes a hydrophobic treatment step before use.

[0007] According to embodiments of this disclosure, the nozzles correspond one-to-one with the pixel slots on the substrate.

[0008] According to embodiments of this disclosure, multiple independent nozzles operate simultaneously, printing a substrate using different colloidal quantum dot inks.

[0009] According to embodiments of this disclosure, a high-throughput inkjet printhead is prepared by 3D printing, and the material used for 3D printing includes one of metals and ceramics.

[0010] According to embodiments of this disclosure, it further includes: a control module for controlling the operating state of the liquid supply unit and for controlling the position of the high-throughput inkjet printhead to align the nozzles with the pixel slots of the substrate.

[0011] The second aspect of this disclosure provides the use of the aforementioned colloidal quantum dot high-throughput inkjet printing apparatus for fabricating spectral chips based on colloidal quantum dots.

[0012] The third aspect of this disclosure provides a high-throughput inkjet printing method for colloidal quantum dots, comprising: S1, using a pneumatic pump to control different colloidal quantum dot inks to enter the inkjet printhead through different inlet pipes; S2, using independent microfluidic channels to extrude different colloidal quantum dot inks from nozzles to form ink droplets; S3, overcoming surface tension, the ink droplets on the surfaces of different nozzles drip onto different positions on the substrate surface to perform inkjet printing. Attached Figure Description

[0013] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0014] Figure 1 This schematic diagram illustrates the structure of a colloidal quantum dot high-throughput inkjet printing apparatus according to an embodiment of the present disclosure.

[0015] Figure 2 A flowchart illustrating a high-throughput inkjet printing method for colloidal quantum dots according to an embodiment of the present disclosure is shown schematically.

[0016] Explanation of icon numbers:

[0017] 1. Pneumatic pump; 2. Liquid storage bottle; 3. Liquid inlet pipe; 4. Microfluidic channel; 5. Nozzle. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0019] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0020] The various directional terms used in this disclosure, such as "front," "back," "left," "right," "up," and "down," are merely for the convenience of description and are used to describe the relative positional relationships between the components, not to limit this disclosure. Different product placement methods may lead to changes in the various directional descriptions.

[0021] This disclosure provides a high-throughput inkjet printing apparatus for colloidal quantum dots. Please refer to [link to relevant documentation]. Figure 1 The system includes: a liquid supply unit, comprising a pneumatic pump 1 and multiple liquid storage bottles 2, wherein the liquid storage bottles 2 contain different colloidal quantum dot inks; the pneumatic pump 1 is used to control the colloidal quantum dot inks to enter the inkjet printhead through the liquid inlet pipe 3; a high-throughput inkjet printhead, comprising multiple independent microfluidic channels 4 and nozzles 5, each microfluidic channel 4 being connected to a corresponding liquid inlet pipe 3, the cross-sectional area of ​​the microfluidic channel 4 gradually decreasing from the inlet end to the outlet end; and nozzles 5 having hollow needle-shaped tips with the tips facing the substrate to be printed, and different colloidal quantum dot inks dripping onto different positions on the substrate through the nozzles 5.

[0022] This high-throughput inkjet printing device mainly consists of two parts: a liquid supply unit and a high-throughput inkjet printhead. A pneumatic pump 1 is connected to multiple liquid storage bottles 2 via short tubes. The short tubes are positioned above the surface of the colloidal quantum dot ink, while a long tube is positioned below it. The long tube connects to the high-throughput inkjet printhead. The pneumatic pump 1 controls the extrusion of colloidal quantum dot ink from the liquid storage bottles 2 through pressure. Specifically, the pneumatic pump 1 pressurizes nitrogen gas into the liquid storage bottles 2 through the short tubes, forcing the colloidal quantum dot ink into the long tube, which then guides the ink into the high-throughput inkjet printhead. The high-throughput inkjet printhead includes multiple microfluidic channels 4, each corresponding to a liquid storage bottle 2, for inkjet printing using different colloidal quantum dot inks.

[0023] The high-throughput inkjet printing apparatus disclosed herein uses a high-throughput inkjet printhead, which can simultaneously print multiple different colloidal quantum dot inks, thereby improving printing efficiency.

[0024] Based on the above embodiments, multiple microfluidic channels 4 are arranged in an array, with an array size of 2×2 to 100×100 and an array period of 0.2 to 2 mm; the diameter of the inlet end cross section of each microfluidic channel 4 is 0.1 to 1 mm.

[0025] The inkjet printhead disclosed herein differs from conventional inkjet printheads. This disclosure features a high-throughput microfluidic channel, and the diameter of the inlet end cross-section of the microfluidic channel 4 is within the aforementioned range, which facilitates the entry of colloidal quantum dot ink into the microfluidic channel 4 through the inlet tube 3.

[0026] Based on the above embodiments, the inner diameter of the needle tip of the nozzle 5 is 10~100μm, and the period is 20~200μm.

[0027] The needle tip inner diameter of nozzle 5 within the above range is beneficial for printing small-sized pixels.

[0028] Based on the above embodiments, the nozzle 5 undergoes a hydrophobic treatment step before use.

[0029] To prevent different inks from contacting each other when they drip from nozzle 5, the tip of nozzle 5 needs to be hydrophobically treated. This makes the ink from nozzle 5 finer, preventing them from contacting each other and allowing them to drip directly into the pixel grooves of the substrate. This effectively avoids mutual interference between multi-array printheads, forms stable ink droplets on the substrate, improves printing accuracy, and reduces the burden on the equipment.

[0030] Based on the above embodiments, the nozzle 5 corresponds one-to-one with the pixel slots on the substrate.

[0031] The nozzle 5 corresponds one-to-one with the pixel groove on the substrate so that the colloidal quantum dot ink can be directly dripped into the pixel groove on the substrate, avoiding the mixing of different colloidal quantum dot inks and affecting subsequent processes.

[0032] Based on the above embodiments, multiple independent nozzles 5 work simultaneously to print on the substrate using different colloidal quantum dot inks.

[0033] Different inks in multiple storage bottles 2 are connected to the inlet of a microfluidic channel 4 via long tubes. Below the outlet are multiple needle-like nozzles 5. The cross-sectional area of ​​the microfluidic channel 4 gradually decreases from the inlet to the outlet, facilitating ink export. When the pneumatic pump 1 operates, it simultaneously compresses the colloidal quantum dot inks in the multiple storage bottles 2. Different colloidal quantum dot inks drip simultaneously onto the substrate surface through different nozzles 5, allowing for the printing of hundreds or thousands of different colloidal quantum dot inks at the same time, thus improving printing efficiency. Of course, this disclosure can also be used for group printing according to actual needs; a single group can print multiple colloidal quantum dot inks.

[0034] Based on the above embodiments, the high-throughput inkjet printhead is prepared by 3D printing, and the material for 3D printing includes one of metals and ceramics.

[0035] 3D printing offers the advantage of one-piece molding, and this disclosure enables the rapid production of the required high-throughput inkjet printhead. The high-throughput inkjet printhead utilizes metal and ceramic materials and possesses technical protection against acid and alkali corrosion.

[0036] Based on the above embodiments, it also includes: a control module for controlling the working state of the liquid supply unit and for controlling the position of the high-throughput inkjet printhead so that the nozzle 5 is aligned with the pixel slot of the substrate.

[0037] The high-throughput inkjet printing device also includes a control module to control the flow rate of colloidal quantum dot ink and to control the position of the high-throughput inkjet printhead for alignment.

[0038] This disclosure also provides an application of the aforementioned colloidal quantum dot high-throughput inkjet printing apparatus for the fabrication of spectral chips based on colloidal quantum dots.

[0039] The high-throughput inkjet printing device disclosed herein can be used to prepare spectral chips based on colloidal quantum dots. Compared with traditional inkjet printing devices that can only print one type of colloidal quantum dot ink at a time, it greatly improves printing efficiency and can quickly prepare the required spectral chips.

[0040] This disclosure also provides a high-throughput inkjet printing method for colloidal quantum dots. Please refer to [link to relevant documentation]. Figure 2 The process includes: S1, using a pneumatic pump 1 to control different colloidal quantum dot inks to enter the inkjet printhead through different inlet pipes 3; S2, using independent microfluidic channels 4 to extrude different colloidal quantum dot inks from nozzles 5 to form ink droplets; S3, the ink droplets on the surfaces of different nozzles 5 overcome surface tension and drip onto different positions on the substrate surface for inkjet printing.

[0041] The high-throughput inkjet printing method includes a control module controlling a pneumatic pump 1 to operate. The pneumatic pump 1 pressurizes nitrogen gas into a reservoir bottle 2, and the colloidal quantum dot ink in the reservoir bottle 2 is forced into a long tube. This long tube guides the colloidal quantum dot ink into the high-throughput inkjet printhead. Different colloidal quantum dot inks sequentially pass through different microfluidic channels 4 and nozzles 5, with droplets accurately falling into the pixel slots of the substrate, completing the inkjet printing. Subsequent operations, such as curing, are involved, but since they are not the focus of this disclosure, they will not be described in detail here.

[0042] In summary, the high-throughput inkjet printing apparatus disclosed herein can simultaneously print multiple different colloidal quantum dot inks, thereby improving inkjet printing efficiency and quality.

[0043] The specific embodiments described above further illustrate the purpose, technical solutions, and beneficial effects of this disclosure. It should be understood that the above descriptions are merely specific embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A colloidal quantum dot high-throughput inkjet printing apparatus, characterized by, include: The liquid supply unit includes a pneumatic pump (1) and multiple liquid storage bottles (2). The multiple liquid storage bottles (2) contain different colloidal quantum dot inks. The pneumatic pump (1) is connected to the multiple liquid storage bottles (2) respectively and is used to control the colloidal quantum dot inks to enter the inkjet printhead through the liquid inlet pipe (3). A high-throughput inkjet printhead includes multiple independent microfluidic channels (4) and nozzles (5). Each microfluidic channel (4) is connected to a corresponding inlet pipe (3). The diameter of the inlet end cross section of each microfluidic channel (4) is 0.1~1mm. The cross-sectional area of ​​the microfluidic channel (4) gradually decreases from the inlet end to the outlet end. The nozzle (5) undergoes a hydrophobic treatment step before use. The nozzle (5) is a hollow needle-shaped tip. The tip faces the substrate to be printed. The nozzle (5) corresponds one-to-one with the pixel groove on the substrate. Different colloidal quantum dot inks are dripped from the nozzle (5) to different positions on the substrate.

2. The colloidal quantum dot high-throughput inkjet printing device according to claim 1, characterized in that, Multiple microfluidic channels (4) are arranged in an array, the array size is 2×2~100×100, and the period of the array is 0.2~2mm.

3. The colloidal quantum dot high-throughput inkjet printing device according to claim 1, characterized in that, The nozzle (5) has a needle tip inner diameter of 10~100μm and a period of 20~200μm.

4. The colloidal quantum dot high-throughput inkjet printing apparatus according to claim 1, characterized in that, Multiple independent nozzles (5) work simultaneously to print on the substrate using different colloidal quantum dot inks.

5. The colloidal quantum dot high-throughput inkjet printing apparatus according to claim 1, characterized in that, The high-throughput inkjet printhead is prepared by 3D printing, and the material used for 3D printing includes one of metals and ceramics.

6. The colloidal quantum dot high-throughput inkjet printing apparatus according to claim 1, characterized in that, Also includes: The control module is used to control the working state of the liquid supply unit and to control the position of the high-throughput inkjet printhead so that the nozzle (5) is aligned with the pixel slot of the substrate.

7. Use of a colloidal quantum dot high-throughput inkjet printing apparatus according to any one of claims 1 to 6 for fabricating a spectral chip based on colloidal quantum dots.

8. A high-throughput inkjet printing method for colloidal quantum dots, characterized in that, The method, applied to the colloidal quantum dot high-throughput inkjet printing apparatus according to any one of claims 1 to 6, comprises: S1, using a pneumatic pump (1) to control different colloidal quantum dot inks to enter the inkjet printhead through different inlet pipes (3); S2, using independent microfluidic channels (4) to extrude different colloidal quantum dot inks from nozzles (5) to form ink droplets; S3, the ink droplets on the surfaces of different nozzles (5) overcome surface tension and drop to different positions on the substrate surface for inkjet printing.

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