CN112735258A

CN112735258A - Quantum dot diffusion plate and quantum dot backlight source

Info

Publication number: CN112735258A
Application number: CN202110057188.3A
Authority: CN
Inventors: 陈雪莲; 叶茂村; 林俊良; 林金汉; 林金锡
Original assignee: Changzhou Almaden Co Ltd
Current assignee: Changzhou Almaden Co Ltd
Priority date: 2021-01-15
Filing date: 2021-01-15
Publication date: 2021-04-30

Abstract

The invention provides a quantum dot diffusion plate and a quantum dot backlight source, wherein the quantum dot diffusion plate comprises a diffusion plate body and a first protective layer arranged on the side edge of the diffusion plate body; the diffusion plate body comprises a glass substrate, a diffusion layer, a quantum dot printing ink layer, an OCA (optically clear adhesive) layer and a second protective layer which are sequentially arranged. According to the quantum dot diffusion plate, the quantum dot ink layer replaces the existing quantum dot film, and the use of film materials is reduced, so that the cost is greatly reduced, and the cost of a quantum dot backlight source is further reduced; simultaneously, this application makes the quantum dot printing ink layer be located an enclosure space through setting up OCA glue film, second protective layer and first protective layer, isolated quantum dot printing ink layer and air contact to avoid the quantum dot printing ink layer to become invalid because of taking place the decay, guarantee the life on quantum dot printing ink layer, and then guarantee the life of quantum dot diffuser plate.

Description

Quantum dot diffusion plate and quantum dot backlight source

Technical Field

The invention relates to the technical field of display screens, in particular to a quantum dot diffusion plate and a quantum dot backlight source.

Background

Compared with the conventional white light LED backlight source, the quantum dot backlight source has the advantages of high color gamut and high contrast, and the picture color is richer; however, the quantum dots have poor thermal stability, and are accelerated to decay when being contacted with water and oxygen, so that the service life is shortened, and the conventional quantum dot backlight mode is a blue light LED + quantum dot film mode at present; due to the high cost of the quantum dot film, the cost of the quantum dot backlight mode is greatly increased compared with the white light LED backlight mode.

Disclosure of Invention

The invention solves the problem that the cost of the prior quantum dot backlight source is higher.

In order to solve the above problems, the present invention provides a quantum dot diffusion plate, which includes a diffusion plate body, and a first protection layer disposed on a side of the diffusion plate body;

the diffusion plate body comprises a glass substrate, a diffusion layer, a quantum dot printing ink layer, an OCA (optically clear adhesive) layer and a second protective layer which are sequentially arranged.

Optionally, the second protective layer is glass.

Optionally, the first protective layer comprises an adhesive-backed PE film.

Optionally, the glass substrate has a thickness in a range of 0.5mm to 1.1 mm.

Optionally, the diffusion layer has a thickness in a range of 30 μm to 80 μm.

Optionally, the thickness of the quantum dot ink layer ranges from 30 ± 3 μm; the light transmittance of the quantum dot ink layer is greater than 95%; the haze of the quantum dot ink layer is lower than 8%.

Optionally, the thickness of the OCA glue layer is 25 μm; the light transmittance of the OCA glue layer is more than 93%; the haze of the OCA glue layer is 0.

Optionally, the thickness of the second protective layer is 0.5 mm; the light transmittance of the second protective layer is 93-94%; the haze of the second protective layer is 0.

Optionally, the haze range of the diffusion plate body is 80% to 100%; the light transmittance of the diffusion plate body is 40% -65%.

Another objective of the present invention is to provide a quantum dot backlight source, which includes the quantum dot diffusion plate, an LED lamp located inside the quantum dot diffusion plate, and a brightness enhancement film layer located outside the quantum dot diffusion plate.

Compared with the prior art, the quantum dot diffusion plate provided by the invention has the following advantages:

according to the quantum dot diffusion plate, the quantum dot ink layer replaces the existing quantum dot film, and the use of film materials is reduced, so that the cost is greatly reduced, and the cost of a quantum dot backlight source is further reduced; simultaneously, this application makes the quantum dot printing ink layer be located an enclosure space through setting up OCA glue film, second protective layer and first protective layer, isolated quantum dot printing ink layer and air contact to avoid the quantum dot printing ink layer to become invalid because of taking place the decay, guarantee the life on quantum dot printing ink layer, and then guarantee the life of quantum dot diffuser plate.

Drawings

Fig. 1 is a cross-sectional view of a prior art quantum dot film backlight;

fig. 2 is a cross-sectional view of a quantum dot diffusion plate of the present invention;

fig. 3 is a cross-sectional view of a quantum dot backlight of the present invention.

Description of reference numerals:

1-diffusion plate body; 11-a glass substrate; 12-a diffusion layer; 13-a quantum dot ink layer; 14-OCA glue line; 15-a second protective layer; 2-a first protective layer; 3-an LED lamp; 4-brightening film layer; 5-a light diffuser plate; 6-quantum dot film.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and intended to be illustrative of the present invention and should not be construed as limiting the present invention, and all other embodiments that can be obtained by one skilled in the art based on the embodiments of the present invention without inventive efforts shall fall within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "circumferential," "radial," and the like are used in the orientations and positional relationships indicated in the drawings for the purpose of simplifying the description, and are not intended to indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be considered as limiting the present invention.

Furthermore, the terms "first" and "second" are used merely to simplify the description and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the first feature being "on" or "under" the first feature may comprise the first feature being in direct contact with the second feature or the first feature being in direct contact with the second feature but being in contact with the second feature by another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. The first feature being "under," "below," and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or merely indicates that the first feature is at a lower level than the second feature.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Because quantum dots have poor thermal stability, in order to avoid the accelerated decay of the quantum dots due to the contact with water, oxygen, etc. during the use process, referring to fig. 1, the conventional quantum dot backlight mode is generally a mode of combining a quantum dot film with an LED light source, specifically, the conventional quantum dot film backlight structure generally includes a light diffusion plate 5, an LED lamp 3 located at one side of the light diffusion plate 5, a quantum dot film 6 located at the other side of the light diffusion plate 5, and a brightness enhancement film layer 4 located at the outer side of the quantum dot film 6, i.e. at the side far from the light diffusion plate 5; in the working process, the LED lamp 3 emits blue light, the blue light passes through the light diffusion plate 5, then passes through the quantum dot film 6, is converted into white light through the quantum dot film 6, and then is emitted through the brightening film layer 4; on one hand, the cost of the quantum dot film 6 is high due to the high price of the film material, so that the cost of the quantum dot film backlight source is high; on the other hand, since the quantum dot film 6 itself has a certain light-shielding property, a part of luminance is lost when light passes through, and the luminance of the quantum dot film backlight is reduced.

In order to solve the problem of high cost of the current quantum dot backlight source, the invention provides a quantum dot diffusion plate, which is shown in fig. 2 and comprises a diffusion plate body 1 and a first protection layer 2 arranged on the side edge of the diffusion plate body 1; the diffusion plate body 1 comprises a glass substrate 11, a diffusion layer 12, a quantum dot ink layer 13, an OCA glue layer 14 and a second protection layer 15 which are sequentially arranged; wherein the diffusion layer 12 is located on the light-emitting surface of the glass substrate 11.

The glass substrate 11 is preferably float glass; diffusion layer 12 and quantum dot printing ink layer 13 are all coated through the mode of printing, and diffusion layer 12 and quantum dot printing ink layer 13 are all coated through the screen printing technology to the preferred in this application.

The composition of the diffusion layer 12 in this application may be any of the diffusion layer compositions that are currently available; the glass substrate 11 is formed into a glass diffusion plate by printing the diffusion layer 12 on the surface of the glass substrate 11.

Further printing a quantum dot ink layer 13 on the surface of the diffusion layer 12, wherein the specific preparation process comprises the steps of uniformly dispersing quantum dot nanoparticles by using an organic solvent, and adding the uniformly dispersed quantum dot nanoparticles into transparent ink according to a certain proportion to prepare quantum dot ink; then, uniformly coating the quantum dot ink on the surface of the diffusion layer 12 to obtain a quantum dot ink layer 13; the specific components and compositions of the quantum dot ink can be any components and compositions in the prior art.

For avoiding quantum dot in quantum dot printing ink layer 13 to accelerate the decay after the contact water oxygen, this application further laminates OCA glue film 14 and second protective layer 15 on quantum dot printing ink layer 13's surface entirely, obtains diffuser plate body 1 to separation water oxygen avoids quantum dot to expose and takes place the decay in the air, improves diffuser plate body 1's life.

Meanwhile, in order to avoid quantum dot attenuation caused by contact between the quantum dot ink layer 13 at the edge of the side edge of the diffusion plate body 1 and air, the first protective layer 2 is further arranged at the side edge of the diffusion plate body 1, so that edge failure caused by direct contact between the quantum dot ink at the edge of the diffusion plate body 1 and water oxygen is prevented through the first protective layer 2; specifically, use diffuser plate body 1 to be square structure as an example, first protective layer 2 in this application sets up in four sides of diffuser plate body 1 to in through being located first protective layer 2 all around, second protective layer 15 and glass substrate 11, enclose to close and constitute a totally closed structure, in order to avoid being located quantum dot printing ink layer 13 and the air contact in this closed structure, prolong its life.

According to the quantum dot diffusion plate provided by the invention, the quantum dot ink layer 13 is used for replacing the existing quantum dot film 6, so that the use of film materials is reduced, the cost is greatly reduced, and the cost of a quantum dot backlight source is further reduced; simultaneously, this application makes quantum dot printing ink layer 13 be located an enclosure space through setting up OCA glue film 14, second protective layer 15 and first protective layer 2, isolated quantum dot printing ink layer 13 and air contact to avoid quantum dot printing ink layer 13 to lose efficacy because of taking place the decay, guarantee quantum dot printing ink layer 13's life, and then guarantee quantum dot diffuser plate's life.

Simultaneously, because the quantum dot diffuser plate that this application provided avoids using the membrane material, avoid causing light shielding nature because of using the membrane material to be favorable to improving the luminance of quantum dot diffuser plate, and then be favorable to improving the whole luminance of quantum dot backlight.

The second protective layer 15 in the present application may be a protective coating capable of protecting the quantum dot ink layer 13, or may be any other structural form capable of protecting the quantum dot ink layer 13; this second protective layer 15 of this application preferred is glass to further this second protective layer 15 of preferred is float glass, so that when realizing carrying out the isolation to quantum dot printing ink layer 13 and air, do not cause light shielding nature, do not influence the luminance of quantum dot diffuser plate, simultaneously, simple structure, the material is easily obtained, is favorable to further reducing the cost of quantum dot diffuser plate.

First protective layer 2 in this application can be for wantonly can be with quantum dot printing ink layer 13 and the isolated structure of air, and this first protective layer 2 of this application preferred includes gum PE membrane to when carrying out quantum dot printing ink layer 13 and air isolated, reduce the preparation degree of difficulty of quantum dot diffuser plate, and further practice thrift the cost.

In order to reduce the cost of the quantum dot diffusion plate and ensure the optical performance of the quantum dot diffusion plate, the thickness range of the glass substrate 1 is preferably 0.5 mm-1.1 mm; the thickness range of the diffusion layer 12 is 30 μm to 80 μm; the thickness range of the quantum dot ink layer 13 is 30 +/-3 mu m; the light transmittance of the quantum dot ink layer 13 is greater than 95%; the haze of the quantum dot ink layer 13 is lower than 8%; the thickness of the OCA glue layer 14 is 25 μm; the light transmittance of the OCA glue layer 14 is more than 93%; the haze of the OCA bondline 14 is 0; the thickness of the second protective layer 15 is 0.5 mm; the light transmittance of the second protective layer 15 is 93-94%; the haze of the second protective layer 15 is 0; the haze range of the diffusion plate body 1 is 80% -100%; the light transmittance of the diffusion plate body 1 is 40-65%; according to the quantum dot diffusion plate provided by the invention, the total thickness range of the diffusion plate body 1 is controlled to be 1.1-1.7 mm.

The application provides a quantum dot diffuser plate, with the transparent printing ink collocation quantum dot nano-particle of low temperature solidification, adopt the screen printing technology, evenly coat the quantum dot on the play plain noodles of glass diffuser plate, when reduce cost, still can improve about 10% with quantum dot backlight brightness.

Another objective of the present invention is to provide a quantum dot backlight source, as shown in fig. 3, which includes the quantum dot diffusion plate as described above, an LED lamp 3 located inside the quantum dot diffusion plate, and a brightness enhancement film layer 4 located outside the quantum dot diffusion plate; the inner side of the quantum dot diffusion plate in the application specifically refers to the side of the quantum dot diffusion plate where the glass substrate 11 is located; specifically, the outer side of the quantum dot diffusion plate is the side of the quantum dot diffusion plate away from the glass substrate 11.

The LED lamp 3 and the brightness enhancement film layer 4 in the application can both adopt corresponding prior art.

In the quantum dot backlight source, the quantum dot ink layer 13 replaces the existing quantum dot film 6 in the quantum dot diffusion plate, so that the use of film materials is reduced, the cost is greatly reduced, and the cost of the quantum dot backlight source is further reduced; simultaneously, this application makes quantum dot printing ink layer 13 be located an enclosure space through setting up OCA glue film 14, second protective layer 15 and first protective layer 2, isolated quantum dot printing ink layer 13 and air contact to avoid quantum dot printing ink layer 13 to lose efficacy because of taking place the decay, guarantee quantum dot printing ink layer 13's life, guarantee the life of quantum dot diffuser plate, and then guarantee the life of quantum dot backlight.

In order to facilitate understanding of the advantages of the quantum dot diffusion plate provided by the present invention, the present application is described in terms of specific embodiments and comparative examples.

Example one

Selecting common float glass with the thickness of 1.1mm as a glass substrate 11, printing a diffusion layer 12 with the thickness of 50 microns on a light-emitting surface of the glass substrate 11, then uniformly coating a quantum dot ink layer 13 with the thickness of 30 microns on the surface of the diffusion layer 12, and pasting an OCA (optically clear adhesive) layer 14 with the thickness of 25 microns and thin glass with the thickness of 0.5mm on the surface of the quantum dot ink layer 13 to be used as a second protective layer 15 to obtain a diffusion plate body 1; and (3) coating a gum PE film with the width of 1.7mm on the side edge of the diffusion plate body 1 to be used as a first protective layer 2, so as to obtain the quantum dot diffusion plate.

Comparative example

Selecting common float glass with the thickness of 1.1mm, and printing a diffusion layer with the thickness of 50 μm on the light-emitting surface of the glass to manufacture the light diffusion plate 5, wherein the light diffusion plate 5 is equivalent to the glass substrate 11 and the diffusion layer 12 in the first embodiment; and adding a quantum dot film 6 on the diffusion plate 5, and adding a brightening film layer on the surface of the quantum dot film 6 to obtain the quantum dot film diffusion plate.

The optical performance and cost of the quantum dot diffusion plate obtained in the first example and the quantum dot film diffusion plate obtained in the comparative example are respectively compared, and the comparison results are shown in table one (in order to ensure the accuracy of the comparison results, in the process of detecting the brightness, the brightness enhancement film layer 4 is added on the surface of the quantum dot diffusion plate obtained in the first example):

watch 1

	Luminance/nits	Light transmittance	Price
				Example one	6140 (brightening film)	50.5% (bare board)	Material adding process $ 10-20/m²
Comparative example	5570 (Quantum dot film and brightening film)	52.4% (bare board)	Film material 60-80 dollar/m²

As can be seen from the above table, after the quantum dot diffuser plate obtained in the first embodiment is covered by the brightness enhancement film layer 4, the measured backlight luminance is 10.2% higher than the backlight luminance of the quantum dot film diffuser plate in the comparative example; after the quantum dot ink layer 13 and the second protective layer 15 are coated on the surface, the numerical value of the reduction of the light transmittance is within 2 percent, and the influence on the brightness of the whole backlight source is small; the diffusion plate with the same size is processed, the price of the quantum dot diffusion plate in the embodiment one is compared with that of the quantum dot film diffusion plate in the comparison example, and the cost of 50-60 dollars can be saved per square meter; therefore, the quantum dot diffusion plate provided by the application greatly reduces the cost while improving the optical performance.

Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and such changes and modifications will fall within the scope of the present invention.

Claims

1. A quantum dot diffusion plate is characterized by comprising a diffusion plate body (1) and a first protective layer (2) arranged on the side edge of the diffusion plate body (1);

the diffusion plate body (1) comprises a glass substrate (11), a diffusion layer (12), a quantum dot printing ink layer (13), an OCA glue layer (14) and a second protection layer (15) which are arranged in sequence.

2. The quantum dot diffusion plate according to claim 1, wherein the second protective layer (15) is glass.

3. The quantum dot diffuser plate according to claim 1, wherein the first protective layer (2) comprises an adhesive-backed PE film.

4. The quantum dot diffuser plate according to any one of claims 1 to 3, wherein the thickness of the glass substrate (1) is in a range of 0.5mm to 1.1 mm.

5. The quantum dot diffusion plate according to claim 4, wherein the thickness of the diffusion layer (12) is in a range of 30 μm to 80 μm.

6. The quantum dot diffusion plate according to claim 4, wherein the quantum dot ink layer (13) has a thickness in a range of 30 ± 3 μm; the light transmittance of the quantum dot ink layer (13) is more than 95%; the haze of the quantum dot ink layer (13) is lower than 8%.

7. The quantum dot diffuser plate according to claim 4, wherein the thickness of the OCA glue layer (14) is 25 μm; the light transmittance of the OCA glue layer (14) is more than 93%; the haze of the OCA glue layer (14) is 0.

8. The quantum dot diffusion plate according to claim 4, wherein the thickness of the second protective layer (15) is 0.5 mm; the light transmittance of the second protective layer (15) is 93-94%; the second protective layer (15) has a haze of 0.

9. The quantum dot diffusion plate according to claim 4, wherein the haze of the diffusion plate body (1) ranges from 80% to 100%; the light transmittance of the diffusion plate body (1) is 40-65%.

10. A quantum dot backlight source, comprising the quantum dot diffusion plate according to any one of claims 1 to 9, LED lamps (3) located inside the quantum dot diffusion plate, and a brightness enhancement film layer (4) located outside the quantum dot diffusion plate.