CN110305531B

CN110305531B - Quantum dot ink and quantum dot color film

Info

Publication number: CN110305531B
Application number: CN201910486243.3A
Authority: CN
Inventors: 方龙; 王允军
Original assignee: Suzhou Xingshuo Nanotech Co Ltd
Current assignee: Suzhou Xingshuo Nanotech Co Ltd
Priority date: 2019-06-05
Filing date: 2019-06-05
Publication date: 2022-12-02
Anticipated expiration: 2039-06-05
Also published as: CN110305531A

Abstract

The invention discloses quantum dot ink which comprises quantum dots, monomers, an initiator and a solvent, wherein the quantum dot ink also comprises oligomers, the boiling points of the oligomers and the monomers are more than 300 ℃, and the boiling point of the solvent is less than 250 ℃. The quantum dot ink can easily control the printing film forming process, so that the thickness of the film has uniformity.

Description

Quantum dot ink and quantum dot color film

Technical Field

The application belongs to the field of nano materials, and particularly relates to quantum dot ink and a quantum dot color film.

Background

The quantum dots have excellent optical properties, and can be applied to the fields of display, illumination and the like. When the quantum dot material is used for display, the color gamut of the display can be obviously improved.

The quantum dots are prepared into quantum dot ink, and a required quantum dot film can be formed by printing, transfer printing, spin coating and other modes. In one application, a quantum dot material is taken as a main body, an additive is added into a solvent component to prepare a proper quantum dot ink, and the quantum dot ink is made to form a color film through a corresponding process, wherein the color film is called as a quantum dot color film.

In the prior art, a printing process is usually adopted to print quantum dot ink on a pixel substrate, and after the quantum dot ink is cured, pixel points on the pixel substrate are formed. However, in the process of printing and film forming of these quantum dot inks, due to the different evaporation rates of the materials, the thickness of the finally formed quantum dot color film is not uniform, which affects the overall optical performance of the quantum dot color film. In addition, the volatility of the existing quantum dot ink is difficult to control, so that the thickness of a formed film in the printing process cannot be kept stable. There is therefore a need for an ink that can maintain a consistent film shrinkage.

Disclosure of Invention

To above-mentioned technical problem, the application provides a quantum dot ink, and it can make the membrane shrinkage keep unanimous, is convenient for control to print the film forming process for the thickness of filming has the homogeneity.

The application provides a quantum dot ink, including quantum dot, monomer, initiator and solvent, wherein, quantum dot ink still includes oligomer, oligomer and monomer's boiling point is greater than 300 ℃, the boiling point of solvent is less than 250 ℃.

Preferably, the oligomer accounts for 10 to 30wt% of the quantum dot ink.

Preferably, the quantum dots account for 0.1 to 10wt% of the quantum dot ink, the monomers account for 10 to 30wt% of the quantum dot ink, the resin accounts for 10 to 30wt% of the quantum dot ink, the initiator accounts for 0.1 to 10wt% of the quantum dot ink, and the solvent accounts for 30 to 70wt% of the quantum dot ink.

Preferably, the oligomer has a viscosity of 10 to 30cp.

Preferably, the oligomer is at least one of polyethylene glycol acrylate and derivatives thereof, triethylene glycol diacrylate and derivatives thereof, triethylene glycol acrylate and derivatives thereof, diethylene glycol diacrylate and derivatives thereof, diethylene glycol acrylate and derivatives thereof, or alkyl methacrylate and derivatives thereof.

Preferably, the quantum dot ink further comprises a resin comprising an acrylic resin, an epoxy resin, a styrene resin, a polyolefin resin, a polyoxyalkylene resin, or a mixture thereof.

Preferably, the solvent includes at least one of ethylene glycol butyl ether, dimethyl imidazolidinone, ethylene glycol butyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol butyl ether, diethylene glycol ethyl ether, or diethylene glycol methyl ethyl ether.

Preferably, the quantum dot ink further comprises a cross-linking agent.

Preferably, the viscosity of the quantum dot ink is 3 to 12cp.

The application also provides a quantum dot color film which is prepared from any one of the quantum dot inks.

According to the method, the low polymer is added into the quantum dot ink, the problem that the film shrinkage rate is inconsistent when the quantum dot ink is dried to form a film is solved, the boiling point of a solvent in the quantum dot ink is lower than 250 ℃, and the boiling points of the low polymer and the monomer are higher than 300 ℃, so that the solvent is easy to volatilize in a short time, the low polymer and the monomer to be solidified are easy to deposit, the printing film forming process is controllable, the thicknesses of the front and back prepared films are relatively consistent, and the finally obtained integral thickness of the quantum dot color film has uniformity.

Drawings

Fig. 1 is a quantum dot color film thickness measurement diagram after a quantum dot ink is printed and formed into a film in an embodiment of the present application.

Detailed Description

The technical solutions in the examples of the present application will be described in detail below with reference to the embodiments of the present application. It should be noted that the described embodiments are only some embodiments of the present application, and not all embodiments.

The application provides a quantum dot ink, including quantum dot, monomer, initiator and solvent, wherein, quantum dot ink still includes oligomer, oligomer and monomer's boiling point be greater than 300 ℃, the boiling point of solvent is less than 250 ℃.

The quantum dot ink in the present application contains a low polymer, and the inventors have found that the problem of non-uniform film shrinkage when the quantum dot ink is dried to form a film can be significantly solved by adding the low polymer.

It is to be noted that the molecular weight is generally 10, which is considered to be more than dimerization ⁴ Hereinafter referred to as oligomers. For example dimers (dimers), trimers (trimers), tetramers (tetramers). The oligomer is selected from polyethylene glycol acrylate and its derivatives, triethylene glycol diacrylate and its derivatives, triethylene glycol acrylate and its derivatives, diethylene glycol diacrylate and its derivatives, diethylene glycol acrylate and its derivatives, or alkyl methacrylate and its derivatives.

In addition, the boiling point of the solvent in the quantum dot ink is lower than 250 ℃, so that the solvent is easy to volatilize in a short time, and the boiling points of the monomer and the oligomer are higher than 300 ℃, so that substances which need to be solidified and are difficult to volatilize are easy to deposit, therefore, the printing film forming process is controllable, the thicknesses of the films prepared before and after are relatively consistent, and the overall thickness of the finally obtained quantum dot color film has uniformity.

The boiling point of the volatile component is less than 250 ℃, the boiling point of the non-volatile component is more than 300 ℃, so that the difference between the boiling points of the volatile component and the non-volatile component is more than 50 ℃, and the volatile component can be volatilized in a short time and the non-volatile component can be quickly reserved. Therefore, the thicknesses of the films of the quantum dot ink printed in front and at the back do not differ too much when the quantum dot ink is printed into the films, and the control of the ink printing film forming process is facilitated.

That is, the quantum dot ink of the present application can be formed in a short time after the completion of ink jet printing, and after that, the thickness of the formed thin film does not change so much, and the thickness of the formed thin film changes little and remains stable. Compared with the film printed before, the film printed before and after has basically the same thickness without great fluctuation, thereby being more convenient for monitoring the ink printing film forming process, and the finally formed film has relatively uniform thickness and uniformity.

On the contrary, if the boiling points of the components in the quantum dot ink are relatively close, the components to be volatilized, such as the solvent and the like, cannot be volatilized in a short time, and the components to be remained, such as the monomer and the like, cannot be deposited in a short time, so that the thickness of the film sprayed and printed can be in various thicknesses along with the time, and the monitoring of the film forming process of the ink printing is very inconvenient. Moreover, since the thicknesses of the films printed before and after are different, the thickness of the finally formed film is very uneven, thereby affecting the overall structure and optical performance of the film.

In short, the volatilization rate of the current quantum dot ink is difficult to control, and the thickness of a formed film in the printing process cannot be kept stable. The volatility of the quantum dot ink in a period of unit time is controllable, so that the film shrinkage rate of the ink can be kept consistent, and the uniformity of final film forming is ensured.

In one embodiment of the present application, the oligomer accounts for 10 to 30wt% of the quantum dot ink, the quantum dot accounts for 0.1 to 10wt% of the quantum dot ink, the monomer accounts for 20 to 60wt% of the quantum dot ink, the initiator accounts for 0.1 to 10wt% of the quantum dot ink, the solvent accounts for 30 to 70wt% of the quantum dot ink,

in one embodiment of the present application, the oligomer has a viscosity of 10 to 30cp, and the quantum dot ink has an overall viscosity of 3 to 7cp. The quantum dot ink is very suitable for ink jet printing by adjusting the oligomer, monomer and solvent components to make the overall viscosity of the quantum dot ink be 3 to 7cp, preferably 5 to 6 cp.

In one embodiment of the present application, a quantum dot ink contains quantum dots, monomers, oligomers, resins, initiators, and solvents. Wherein the monomers, oligomers and resins have a boiling point greater than 300 ℃, for example, the resins may be selected from acrylic resins, epoxy resins, styrenic resins, polyolefin resins, polyoxyalkylene resins, or mixtures thereof; for example, the monomer may be selected from isobornyl acrylate monomer (IBOA), isobornyl methacrylate (IBOMA), trimethylolpropane triacrylate (TMPTA), tripropylene glycol diacrylate (TPGDA), and the like.

In one embodiment of the present application, the quantum dot ink contains quantum dots, monomers, oligomers, resins, initiators and solvents, which can be selected from ethylene glycol butyl ether, dimethyl imidazolidinone, ethylene glycol butyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol butyl ether, diethylene glycol ethyl ether, or diethylene glycol methyl ethyl ether.

In one embodiment of the present application, the quantum dot ink contains quantum dots, monomers, oligomers, resins, initiators and solvents, and the quantum dot ink further contains a volatile monomer having a boiling point of less than 250 ℃. For example, the volatile monomer may be selected from octyl methacrylate, decyl methacrylate, 4-hydroxybutyl vinyl ether, hydroxyethyl acrylate, hydroxypropyl methacrylate, isooctyl acrylate, hydroxypropyl acrylate, or hydroxypropyl methacrylate.

In a specific embodiment of the present application, a quantum dot ink contains quantum dots, monomers, oligomers, resins, initiators, and solvents. The quantum dot ink further includes a cross-linking agent, for example, the cross-linking agent may be selected from trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, or hexapentaerythritol hexaacrylate, etc.

The quantum dot ink of the present application contains an initiator, and the initiator may be a photoinitiator or a thermal initiator, or both. For example, the initiator is a photoinitiator that is TPO (2,4,6-trimethylbenzoyl-diphenylphosphine oxide).

In a specific embodiment of the present application, a quantum dot ink contains quantum dots, monomers, oligomers, resins, initiators, and solvents. The ink comprises, by weight, 5wt% of quantum dot ink, 20wt% of monomer, 15wt% of oligomer, 10wt% of resin, 5wt% of initiator and 45wt% of solvent, wherein the boiling points of the resin, oligomer and monomer are more than 300 ℃, and the boiling point of the solvent is less than 250 ℃.

In a specific embodiment of the present application, a quantum dot ink contains quantum dots, monomers, oligomers, resins, initiators, and solvents. The ink comprises, by weight, quantum dots 10wt%, monomers 25wt%, oligomers 15wt%, resin 5wt%, initiators 1wt%, and solvents 44wt%, wherein the boiling points of the resins, oligomers, and monomers are greater than 300 ℃, and the boiling point of the solvents is less than 250 ℃.

In one embodiment of the present application, a quantum dot ink includes quantum dots, monomers, oligomers, resins, initiators, and solvents. The ink comprises, by weight, 2wt% of quantum dot ink, 30wt% of monomer, 30wt% of quantum dot ink, 30wt% of oligomer, 5wt% of resin, 3wt% of initiator and 30wt% of solvent, wherein the boiling points of the resin, oligomer and monomer are more than 300 ℃, and the boiling point of the solvent is less than 250 ℃.

In summary, the quantum dot ink in the present application includes a volatile solvent and a non-volatile monomer, a low polymer and a resin, the boiling point of the volatile solvent and the volatile monomer is less than 250 ℃, the boiling point of the non-volatile resin, the boiling point of the monomer and the low polymer is greater than 300 ℃, so that the difference between the boiling points is greater than 50 ℃, thereby the volatile component can be volatilized in a short time, and the non-volatile component can be retained quickly, so that the thicknesses of the films of the quantum dot ink printed before and after the film formation do not differ too much, and the control of the printing film formation process is facilitated.

The application further provides a quantum dot color film, the quantum dot color film is prepared from quantum dot ink, the quantum dot ink comprises quantum dots, monomers, an initiator and a solvent, wherein the quantum dot ink further comprises oligomers, the boiling points of the oligomers and the monomers are greater than 300 ℃, and the boiling point of the solvent is less than 250 ℃.

The application further provides a quantum dot color film, the quantum dot color film is prepared from quantum dot ink, the quantum dot ink comprises quantum dots, a monomer, an initiator and a solvent, and the quantum dot ink further comprises resin. For example, the resin may be selected from an acrylic resin, an epoxy resin, a styrene resin, a polyolefin resin, a polyoxyalkylene resin, or a mixture thereof; for example, the monomer may be selected from isobornyl acrylate monomer (IBOA), isobornyl methacrylate (IBOMA), trimethylolpropane triacrylate (TMPTA), tripropylene glycol diacrylate (TPGDA), and the like.

In one embodiment of the present application, the quantum dot color film contains a low polymer, and the inventors have found that the problem of inconsistent film shrinkage when the quantum dot ink is dried to form a film can be significantly reduced by adding the low polymer.

In a specific embodiment of the application, the thicknesses of the quantum dot color films are relatively consistent, and the film forming process is controllable.

In addition, the manufacturing process of the quantum dot color film is generally implemented by an inkjet printing method, and details about the inkjet printing technology are well known to those skilled in the art and will not be described herein.

To better illustrate the advantages of the present application, fig. 1 is a graph showing the thickness measurement of the color film of the quantum dots after the quantum dot ink is cured in a specific embodiment of the present application. The thickness in the figure is in micrometers (μm). And (3) respectively spraying quantum dot ink on the color film substrate with the groove, respectively selecting 3 positions (point A, point B and point C) of different printing time points, and measuring the film thickness of each point by using a step profiler. Wherein, the film thickness of the point A is 7.17 microns, the film thickness of the point B is 7.15 microns, and the film thickness of the point C is 7.18 microns. Therefore, although the time for printing the ink at the three positions of the point A, the point B and the point C is different, the thicknesses of the ink printing films at the three positions of the point A, the point B and the point C are close, so that the spraying and printing process of the whole thin film is controllable, the thicknesses of the finally formed thin films are basically consistent, and the quantum dot color film has good uniformity.

In a word, the quantum dot color film prepared by the quantum dot ink has a controllable printing film forming process and good film forming uniformity.

Although the present disclosure has been described and illustrated in greater detail by the inventors, it should be understood that modifications and/or alterations to the above-described embodiments, or equivalent substitutions, will be apparent to those skilled in the art without departing from the spirit of the disclosure, and that no limitations to the present disclosure are intended or should be inferred therefrom.

Claims

1. The quantum dot ink comprises quantum dots, a monomer, an initiator and a solvent, and is characterized by further comprising an oligomer, wherein the boiling points of the oligomer and the monomer are more than 300 ℃, the boiling point of the solvent is less than 250 ℃, the difference between the boiling points of the oligomer and the monomer and the solvent is more than 50 ℃, the viscosity of the oligomer is 10 to 30cp, the viscosity of the quantum dot ink is 3 to 12cp, the oligomer is polyethylene glycol acrylate and derivatives thereof, triethylene glycol diacrylate and derivatives thereof, diethylene glycol acrylate and derivatives thereof, or at least one of alkyl methacrylate and derivatives thereof, and the oligomer accounts for 10 to 30wt% of the quantum dot ink, the quantum dots account for 0.1 to 10wt% of the quantum dot ink, the monomer accounts for 20 to 60wt% of the quantum dot ink, the initiator accounts for 0.1 to 10wt% of the quantum dot ink, and the solvent accounts for 30 to 70wt% of the quantum dot ink.

2. The quantum dot ink of claim 1, further comprising a resin comprising an acrylic resin, an epoxy resin, a styrene resin, a polyolefin resin, a polyoxyalkylene resin, or a mixture thereof.

3. The quantum dot ink of claim 1, wherein the solvent comprises at least one of ethylene glycol butyl ether, dimethyl imidazolidinone, ethylene glycol butyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol butyl ether, diethylene glycol ethyl ether, or diethylene glycol methyl ethyl ether.

4. The quantum dot ink of claim 1, further comprising a crosslinker.

5. A quantum dot color film prepared from the quantum dot ink of claim 1~4.