CN106374028A - Quantum dot film and preparation method thereof - Google Patents

Abstract

The invention discloses a quantum dot film and a preparation method therefor. The quantum dot film comprises a substrate, a quantum dot layer, a buffer layer, a protection layer, a water-oxygen blocking layer, and a curing layer, wherein the buffer layer is used for sticking and fixing the quantum dot layer with the substrate; the protection layer is formed on the quantum dot layer to seal and package the quantum dot layer so as to protect the quantum dot layer; the water-oxygen blocking layer is used for sealing and packaging the substrate, the buffer layer, the quantum dot layer and the protection layer in the interior of the water-oxygen blocking layer; and the curing layer is used for sealing and packaging the water-oxygen blocking layer in the interior of the curing layer. According to the quantum dot film provided by the invention, the quantum dot layer and the water-oxygen blocking layer are fully packaged and protected in an all-around manner, so that the quantum dot film has relatively high structural stability and relatively long service life.

Description

Quantum dot film and preparation method thereof

technical field

The invention relates to the display field, in particular to a quantum dot film and a preparation method thereof.

Background technique

At present, the mainstream display on the market is LCD mode, which requires an active light source, superimposed on the RGB color filter on the panel, and realizes the transformation of light and dark and color by controlling the direction of the liquid crystal. This technology is favored by the market due to its mature technology, high yield rate and relatively low cost. But its low color saturation has also been criticized. Therefore, the industry has carried out extensive research and development on LCD color gamut enhancement technology, which includes the improvement of LED's own phosphor technology, and also includes adding another mechanism or film besides LED, such as quantum dot film to increase the color gamut . The luminescent principle of quantum dot materials is to emit red and green light after being excited by blue light of a specific wavelength band. Due to its high light conversion efficiency and narrow luminous wavelength band, it can obtain a high-quality color gamut of more than 100% in NTSC, and has been sought after by the industry. However, due to the insufficient heat resistance and water and oxygen resistance of the quantum dot material, its production becomes complicated and expensive. For example, a quantum dot film (its English name is Quantum Dot Enhancement Film, referred to as QDEF) protected by two upper and lower water-oxygen barrier films is made, and the entire surface is applied to the display backlight unit or encapsulated in a glass tube for side-entry backlight units. .

There are two main types of light-emitting devices for existing quantum dot products that are widely used in mass production.

One is the quantum dot thin film product (QDEF) in the On surface application mode. The upper and lower water and oxygen barrier films protect the quantum dots from water and oxygen in the upper and lower directions. The main disadvantages of this light-emitting device are: first, it covers the entire display area, and the cost is high; second, there is no water and oxygen barrier protection on the side of the QDEF, and it is easy to cause the edge area to fail; Cause regional failure, cause the whole machine display to fail, and the loss is multiplied.

The other is the QD tube in the On Edge application mode. Its main structure is a strip glass tube encapsulating quantum dots, which is used for side-entry backlight structures. Its main disadvantage is that the application mode is limited and can only be used for side entry.

Contents of the invention

The first object of the present invention is to provide a quantum dot film with high structural stability and long service life in view of the problems in the background technology.

In order to achieve above-mentioned first object, technical scheme of the present invention is:

A quantum dot film comprising:

Substrate;

quantum dot layer;

a buffer layer, which bonds and fixes the quantum dot layer and the substrate;

a protective layer, which is formed on the quantum dot layer and encapsulates the quantum dot layer to protect the quantum dot layer;

a water-oxygen barrier layer encapsulating the substrate, the buffer layer, the quantum dot layer and the protective layer; and

The solidified layer completely encapsulates the water-oxygen barrier layer to protect the water-oxygen barrier layer.

In some embodiments of the present invention, the substrate is a polymer material. More preferably, the substrate is made of PET material.

In still some preferred embodiments of the present invention, the protective layer is a high temperature resistant resin. More preferably, the protective layer is one of three high-temperature-resistant resins: acrylic resin, epoxy resin or polyimide resin.

The second object of the present invention is to provide a method for preparing a quantum dot film with the above structure in view of the problems in the background technology.

In order to achieve the above-mentioned second purpose, the technical solution of the present invention is:

A preparation method of the quantum dot film with the above structure, comprising:

Provide the substrate;

forming a buffer layer on the substrate;

forming a quantum dot layer on the buffer layer;

forming a protective layer encapsulating the quantum dot layer on the quantum dot layer;

forming a water and oxygen barrier layer encapsulating the substrate, the buffer layer, the quantum dot layer and the protective layer;

A cured layer encapsulating the water and oxygen barrier layer is formed.

In some preferred embodiments of the present invention, the water-oxygen barrier layer is formed by atomic deposition technology.

The advantages of the present invention are:

1. The quantum dot layer in the quantum dot film of the present invention is encapsulated and protected from top, bottom, left and right by the corresponding structural layer, which effectively improves the aging resistance of the quantum dot layer and increases its service life.

2. The water-oxygen barrier layer in the quantum dot film of the present invention is fully protected by the solidified layer that fully encapsulates it, so that the water-oxygen barrier layer can be protected from damage everywhere.

3. The water and oxygen barrier layer covers the side of the quantum dot layer, so that the side of the quantum dot layer can also be protected by water and oxygen.

4. The water-oxygen barrier layer does not need to cover the entire surface of the substrate, which reduces the material cost, and avoids the regional failure caused by a point defect in the traditional technology due to the full-surface application of the water-oxygen barrier film, and the display of the whole machine Problems of failure and loss multiplied.

5. The quantum dot film of the present invention uses a flexible polymer material layer as the substrate, and a buffer layer with bonding properties is laid between the substrate and the quantum dot layer, so that the light-emitting device has excellent optical properties and anti-stripping performance.

6. The quantum dot layer in the quantum dot film of the present invention is composed of a special formula, and the chromaticity can realize more than 100% NTSC and white balance.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment:

Fig. 1 is the structural representation of quantum dot film in the embodiment of the present invention;

Fig. 2 is the spectrogram obtained under the excitation of the LED blue light source by the quantum dot film of the present embodiment of the present invention;

Among them: 1-substrate, 2-buffer layer, 3-quantum dot layer, 4-protective layer, 5-water oxygen barrier layer, 6-cured layer.

detailed description

The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings. The present invention can be implemented in many different forms, and is not limited to the embodiments described in this embodiment. The purpose of providing the following specific embodiments is to facilitate a clearer and more thorough understanding of the disclosure of the present invention, wherein the words indicating orientation such as up, down, left, and right are only for the positions of the structures shown in the corresponding drawings.

However, those skilled in the art may recognize that description of one or more of the specific details may be omitted, or other methods, components or materials may also be used. In some instances, some implementations were not described or described in detail.

In addition, the technical features and technical solutions described herein can also be combined in any suitable manner in one or more embodiments. It is readily understood by those skilled in the art that the steps or sequence of operations of methods related to the embodiments provided herein can also be changed. Therefore, any order in the figures and examples is for illustrative purposes only and does not imply a certain order unless explicitly stated to do so.

Fig. 1 shows a specific embodiment of this quantum dot film of the present invention, and it comprises substrate 1, buffer layer 2, quantum dot layer 3, protective layer 4, water oxygen barrier layer 5 and cured layer 6 that are closely bonded together . in:

The substrate 1 is a flexible polymer material, specifically PET material in this embodiment. Of course, the substrate 1 can also use other layered materials.

The buffer layer 2 is equivalent to a layer of adhesive, which is used to bond and fix the quantum dot layer 3 and the substrate 1 to enhance the peeling force between the quantum dot layer 3 and the substrate 1 .

The quantum dot layer 3 is arranged on the buffer layer 2. The quantum dots in the quantum dot layer 3 are composed of a certain ratio of red quantum dots and green quantum dots. Under the excitation of a blue light source, red and green light of specific wavelength bands will be emitted. , due to its narrow half-peak width, red and green bands do not overlap, which can effectively improve the color saturation of the display.

The protection layer 4 is formed on the quantum dot layer 3 and encapsulates the quantum dot layer 3, so that all parts of the quantum dot layer 3 can be well protected. This is because the structure of the quantum dot layer 3 is unstable, so the protective layer 4 needs to be formed immediately after film formation for pre-protection. Apparently, the protection layer 4 is formed with materials capable of protecting the stability of the quantum dot layer structure. Considering that the water-oxygen barrier layer 5 on the protective layer 4 needs to undergo high-temperature treatment during production, the protective layer 4 is preferably made of high-temperature-resistant resin materials, such as acrylic resins, epoxy resins, and polyimide resins. .

In fact, the combination of the protective layer 4 and the substrate 1 is better, and it is not necessary to use the buffer layer 2 to enhance the peeling force between the protective layer 4 and the substrate 1. Therefore, the protective layer 4 and the substrate in FIG. 1, the buffer layer at the junction is partially removed, so that the lower part of the protective layer 4 is directly connected to the substrate 1 (not the buffer layer) (the two are no longer indirectly connected through the buffer layer 2). The reason why this embodiment retains the buffer layer structure at the junction of the protective layer 4 and the substrate 1 is based on the consideration of simplifying the manufacturing process.

The water and oxygen barrier layer 5 encapsulates the substrate 1 , the buffer layer 2 , the quantum dot layer 3 and the protective layer 4 inside, and is a layer structure with a certain water and oxygen barrier function. The water and oxygen barrier layer 5 can be made of inorganic materials, or can be composed of multilayer films of inorganic materials and organic materials. The water-oxygen barrier rate of the water-oxygen barrier layer 5 is generally at the level of 10^-1 to -2, and may be higher, mainly to meet the needs of protecting the quantum dot layer.

The cured layer 6 completely encapsulates the water-oxygen barrier layer 5 inside, so as to protect all parts of the water-oxygen barrier layer 5 from being damaged. Apparently, the cured layer 6 is formed of a material capable of protecting the structural stability of the water-oxygen barrier layer 5 . In this embodiment, the cured layer is formed by resin coating. Different from the above-mentioned protective layer 4, the cured layer 6 does not have to be made of high-temperature-resistant resin material, and there is no requirement for high-temperature resistance.

We tested the quantum dot film of this embodiment under the excitation of the LED blue light source, and the obtained spectrum is shown in Figure 2. It can be seen from Figure 2 that the red light obtained by the excitation of the quantum dot film And green light has a narrow emission band and high purity, which can effectively increase the color gamut and improve color saturation.

Shown in Fig. 1 again, the preparation method of this quantum dot film of the present embodiment comprises the following steps:

1) A substrate 1 formed of a PET film is provided.

2) Forming a buffer layer 2 on the substrate 1, the coating thickness of the buffer layer 2 is preferably between 5-10 microns.

3) Forming the quantum dot layer 3 on the buffer layer 2 .

4) Form a protective layer 4 on the quantum dot layer 3 to enclose the quantum dot layer.

5) The water-oxygen barrier layer 5 is formed by atomic deposition technology, and the water-oxygen barrier layer 5 encapsulates the substrate 1 , the buffer layer 2 , the quantum dot layer 3 and the protective layer 4 inside.

6) Forming the solidified layer 6, and the solidified layer 6 fully encapsulates the water and oxygen barrier layer 5 inside.

Various raw materials adopted in each of the above-mentioned embodiments can be purchased from outside or prepared by conventional methods.

The above content is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. Those of ordinary skill in the technical field to which the present invention belongs can also make some simple deduction or replacement without departing from the concept of the present invention.

Claims (7)

1. A quantum dot film, characterized in that, comprising: Substrate (1); quantum dot layer (3); a buffer layer (2), which bonds and fixes the quantum dot layer (3) and the substrate (1); A protective layer (4), which is formed on the quantum dot layer (3) and encapsulates the quantum dot layer (3), so as to protect the quantum dot layer (3); A water and oxygen barrier layer (5), which encapsulates the substrate (1), the buffer layer (2), the quantum dot layer (3) and the protective layer (4) therein; and A solidified layer (6), which encapsulates the water-oxygen barrier layer (5) therein, so as to protect the water-oxygen barrier layer (5). 2. The quantum dot film according to claim 1, characterized in that, the substrate (1) is a polymer material. 3. The quantum dot film according to claim 2, characterized in that the substrate (1) is a PET material. 4. The quantum dot film according to claim 1, characterized in that, the protective layer (4) is a high temperature resistant resin. 5. The quantum dot film according to claim 4, characterized in that, the protective layer (4) is an acrylic resin, an epoxy resin or a polyimide resin. 6. A method for preparing a quantum dot film according to any one of claims 1 to 5, characterized in that, comprising: providing a substrate (1); forming a buffer layer (2) on the substrate (1); forming a quantum dot layer (3) on the buffer layer (2); forming a protective layer (4) enclosing the quantum dot layer (3) on the quantum dot layer (3); forming a water and oxygen barrier layer (5) encapsulating the substrate (1), the buffer layer (2), the quantum dot layer (3) and the protective layer (4) therein; A cured layer (6) encapsulating the water and oxygen barrier layer (5) is formed. 7. The preparation method according to claim 6, characterized in that, the water-oxygen barrier layer (5) is formed by atomic deposition technology.