WO2020253217A1

WO2020253217A1 - Circuit board and display screen

Info

Publication number: WO2020253217A1
Application number: PCT/CN2019/130342
Authority: WO
Inventors: 孙天鹏; 张金刚; 胡新喜
Original assignee: 深圳市洲明科技股份有限公司
Priority date: 2019-06-19
Filing date: 2019-12-31
Publication date: 2020-12-24
Also published as: CN110225651A; CN110225651B

Abstract

A circuit board and a display screen (10). The circuit board comprises a substrate (100) and a circuit layer (200), wherein the circuit layer (200) is arranged on the substrate (100); and a face, facing the circuit layer (200), of the substrate (100) is provided with an optical barrier layer (300), wherein the raw materials of the optical barrier layer (300) comprise a white pigment, and a face, facing away from the substrate (100) and the circuit layer (200), of the optical barrier layer (300) is provided with an ink layer (400). When the circuit board is used for manufacturing the display screen (10), lamp beads (120) are provided on the circuit layer (200), and after the lamp beads (120) are extinguished, the optical barrier layer (300) can reflect white light, so as to prevent the color of the substrate (100) from reflecting onto the circuit board, and maintain the color consistency of the ink layer (400), thereby ensuring the color consistency of the display screen (10) after the lamp beads (120) are extinguished.

Description

Circuit board and display

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office with application number 201910529444.7 and application name "Circuit Board and Display Screen" on June 19, 2019, the entire content of which is incorporated into this application by reference.

Technical field

This application relates to the field of display technology, in particular to circuit boards and display screens.

Background technique

The current display screen is composed of a circuit board and the lamp beads set on it. After the display screen is off, that is, after the lamp beads are extinguished, when the external light source shines on the circuit board, it will reflect the color of the circuit board and reflect on the circuit board. The output color easily affects the overall color of the display screen after rest, resulting in poor color consistency of the display screen.

Summary of the invention

According to various embodiments of the present application, a circuit board and a display screen are provided.

A circuit board comprising a substrate and a circuit layer, the circuit layer is arranged on the substrate, the substrate is provided with an optical barrier layer on the side facing the circuit layer, and the raw material of the optical barrier layer includes white pigment An ink layer is provided on the side of the optical barrier layer away from the substrate and the circuit layer.

A display screen includes lamp beads and a circuit board, the circuit board includes a substrate and a circuit layer, the circuit layer is arranged on the substrate, and the substrate is provided with an optical barrier layer on the side facing the circuit layer, so The raw materials of the optical barrier layer include white pigments, an ink layer is provided on the side of the optical barrier layer away from the substrate and the circuit layer, the lamp beads are arranged on the circuit board, and the lamp beads Connect with the circuit layer. The details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, purposes and advantages of this application will become apparent from the description, drawings and claims.

Description of the drawings

FIG. 1 is a schematic diagram of a cross-sectional structure of a display screen according to an embodiment;

Fig. 2 is a schematic cross-sectional structure diagram of a display screen of another embodiment.

Detailed ways

In order to facilitate the understanding of the application, the application will be described in a more comprehensive manner with reference to the relevant drawings. The preferred embodiments of the application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the implementation described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of this application more thorough and comprehensive.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of this application. The terminology used in the specification of the application herein is only for the purpose of describing specific embodiments, and is not intended to limit the application. The term "and/or" as used herein includes any and all combinations of one or more related listed items.

With the continuous development of LED (Light Emitting Diode) display technology, the display effect of LED displays has been rapidly improved, and both the pixel pitch and the display effect have made great progress. With the advent of the 5G era, the Internet of Things and the promotion of artificial intelligence, as an important interactive information display window, LED displays will be further widely used with their technical advantages of seamless splicing and large-screen display. LED displays are moving towards higher definition and better picture quality. At present, the pitch of the LED display is gradually reduced, and it has been developed to below P1.0. The display clarity has made a qualitative leap. The display with pitch below P1.0 is mainly based on Mini-LED display technology. At present, the technology in this field is divided into SMD (Surface Mounted Devices) products, and Mini-LED display products integrated with PCB. The reduction of pixel pitch also makes people look at the display screen closer and closer, so that people's attention and requirements for the display screen are not only the display effect itself, but also extend to the appearance of the screen. From the original single-scale application, it gradually enters the stage of specialized and individualized multiple applications. The current display screen is composed of a circuit board and the lamp beads set on it. After the display screen is off, that is, after the lamp beads are extinguished, when the external light source shines on the circuit board, it will reflect the color of the circuit board and reflect on the circuit board. The output color easily affects the overall color of the display screen after rest, resulting in poor color consistency of the display screen.

In one of the embodiments, as shown in FIG. 1, a circuit board is provided, which includes a substrate 100 and a circuit layer 200, the circuit layer 200 is disposed on the substrate 100, and the substrate 100 faces the circuit layer 200 An optical barrier layer 300 is provided on one side of the optical barrier layer 300. The raw material of the optical barrier layer 300 includes a white colorant. That is, the optical barrier layer 300 is used to reflect white light, that is, the color of the optical barrier layer 300 is white. The optical barrier layer 300 is set in white, and an ink layer 400 is provided on a side of the optical barrier layer 300 away from the substrate 100 and the circuit layer 200.

Specifically, the optical barrier layer 300 is made of raw materials including white pigments, so that the optical barrier layer 300 is white. It should be understood that the optical barrier layer 300 is white because when visible light is irradiated to the optical When on the barrier layer, the optical barrier layer 300 can reflect white light, that is, the optical barrier layer 300 is used to reflect all colors of light, so that the optical barrier layer 300 is white.

In order to achieve the white color of the white colorant, in one embodiment, the white colorant includes at least one of titanium white pigment, lithopone, zinc oxide and antimony white. In an embodiment, the white colorant includes titanium dioxide, or in other words, the white colorant includes titanium white, so as to realize the function of the white colorant to appear white. In one embodiment, the white colorant includes at least one of zinc sulfide and barium sulfate. In one embodiment, the white colorant includes zinc oxide. In one embodiment, the white colorant includes antimony trioxide. It should be understood that the white colorant may also be other pigments that can appear white, and the description will not be redundant in this embodiment.

It should be understood that the substrate can be insulated, that is, the substrate is an insulating substrate, the substrate may also be referred to as an insulating layer, the substrate is used to carry the circuit layer, and the material of the substrate may be a prepreg ), at least one of resin and glass. In one embodiment, the substrate is a prepreg substrate. In one embodiment, the substrate is a resin substrate. In one embodiment, the substrate is a glass substrate. In the above embodiments, the substrate can be used to carry the circuit layer.

In this embodiment, as shown in FIG. 1, the optical barrier layer 300 covers the substrate 100 and is disposed on the side facing the circuit layer 200. In one embodiment, the optical barrier layer covers the substrate where the substrate is not disposed. The position of the circuit layer is to reflect light through the optical barrier layer to prevent light from irradiating the substrate of the circuit board, so as to prevent the reflected light of the substrate from being projected on the ink layer, thereby improving the color consistency of the ink layer.

In this embodiment, the material of the circuit layer includes copper, and the circuit layer is made by pressing copper foil on one side of the substrate, and then performing the steps of laminating, exposing, developing, etching and removing the film on the copper foil. .

Please refer to FIG. 1, the above circuit board, when light is irradiated on the circuit board, and the light passes through the ink layer 400 and irradiates on the optical barrier layer 300, since the raw material of the optical barrier layer 300 includes white colorant, the optical The barrier layer 300 can reflect white light, and a white background color will be transmitted on the ink layer 400, and because the optical barrier layer 300 can reflect white light, it is difficult for light to pass through the optical barrier layer 300, so that the light does not shine on the circuit board. The position within the layer 300 does not reflect the color of the substrate 100 on the circuit board, and the ink layer 400 is used to set the desired color according to the actual situation. Since the color projected on the ink layer 400 is all white, although it will increase The brightness of the ink layer 400 does not change the color of the ink layer 400 itself, so the color consistency of the ink layer 400 can be better maintained.

When the above-mentioned circuit board is used to make the display screen, the lamp beads are arranged on the circuit layer 200. When the lamp beads are extinguished, the optical barrier layer 300 can reflect white light, thereby avoiding reflecting the color of the substrate 100 on the circuit board, thereby maintaining the ink layer The color consistency of 400 ensures the color consistency of the display screen after the lamp bead is extinguished.

It should be understood that the optical barrier layer 300 may also be at least partially disposed on the substrate 100 to reflect part of the white light accordingly. As shown in FIG. 1, in one embodiment, the optical barrier layer 300 covers at least a part of the circuit layer 200, so that light does not irradiate the circuit layer 200 to form the reflective color of the circuit layer 200, and avoid the circuit layer 200 The color of φ is projected on the ink layer 400 to better ensure the color consistency of the ink layer 400. In one embodiment, as shown in FIG. 1, the circuit layer 200 includes a circuit body (not shown) and a plurality of pads 210, and the circuit body is connected to each of the pads 210, and the optical barrier layer 300 covers the circuit body and the substrate 100, so as to prevent light from being irradiated on the circuit body and the substrate 100, thereby preventing the color reflected by the circuit body and the substrate 100 from affecting the color of the circuit board Consistency, and the optical barrier layer 300 and the ink layer 400 disposed on the surface of the optical barrier layer 300 can play a role of solder resist to protect the circuit body.

To protect the circuit layer 200 of the circuit board, in one of the embodiments, as shown in FIG. 2, the circuit board further includes a solder resist layer 500, and the circuit layer 200 includes a circuit body (not shown) and a plurality of solder masks. And the circuit body is connected to each of the pads 210, the solder resist layer 500 is disposed on the circuit body and the substrate 100, the solder resist layer 500 is provided with an opening, and the opening Aligned with each of the pads 210, the optical barrier layer 300 is provided on the surface of the solder resist layer 500. The solder resist layer 500 is used to protect the circuit body when welding parts on the circuit board to prevent the circuit body from breaking and short-circuiting. In this embodiment, a window is opened at the position of the solder resist layer 500 corresponding to the pad 210 to form the opening. In a conventional circuit board, light is irradiated onto the substrate 100 through the solder resist layer 500, which will affect the color of the solder resist layer 500. At the same time, the color of the solder resist layer 500 is difficult to maintain color consistency due to process problems. In this application, the optical barrier layer 300 is disposed on the surface of the solder resist layer 500, so as to filter out the light irradiated on the substrate 100 and the solder resist layer 500, thereby avoiding reflections on the substrate 100 and the solder resist layer 500 The light affects the color of the ink layer 400, and the color consistency of the ink layer 400 is better maintained.

In this embodiment, the number of the openings is multiple, and the openings are arranged in a one-to-one correspondence with the pads, that is, each opening is aligned with one of the pads.

In order to realize the setting of the optical barrier layer, in one of the embodiments, the optical barrier layer is disposed on the side of the substrate facing the circuit layer by printing, and the accuracy of setting the optical barrier layer by printing is higher, thereby Better ensure the color consistency of the optical barrier layer.

In order to realize the function of the optical barrier layer, in one of the embodiments, the raw material of the optical barrier layer is at least one of photocurable ink, thermosetting ink and volatile ink. It should be understood that the current solder mask inks include green, black, blue, etc., but there is no white, and the solder mask ink cannot be adjusted to white at present, so the material of the optical barrier layer is different from the material of the solder mask ink.

In one of the embodiments, the raw material of the optical barrier layer is ultraviolet curable ink, that is, UV (ultraviolet) ink, that is, the optical barrier layer is the first ultraviolet curable ink layer. UV-curable inks are currently widely used inks, and can better realize the function of the optical barrier layer.

In one of the embodiments, the raw material of the ink layer is at least one of photocurable ink, thermosetting ink and volatile ink. Therefore, the function of the ink layer is realized by the above-mentioned materials, and the color consistency of the ink layer can be controlled more conveniently.

In one of the embodiments, the raw material of the ink layer is ultraviolet curable ink, that is, UV (ultraviolet) ink, that is, the ink layer is a second ultraviolet curable ink layer. UV-curable inks are currently widely used inks and can better realize the function of the ink layer.

In order to realize the setting of the ink layer, in one of the embodiments, the ink layer is set on the side of the optical barrier layer away from the substrate and the circuit body layer by printing, and the accuracy of setting the ink layer by printing is Higher, so as to better ensure the color consistency of the ink layer.

It should be understood that the raw material of the solder mask is solder mask ink, and the viscosity of the solder mask ink is high. Therefore, before using the solder mask, a diluent needs to be added to it to reduce the viscosity of the solder mask. Screen the group soldering ink on the substrate and circuit body. After the diluent is added to the solder resist ink, the solder resist ink containing the diluent is coated on the surface of the substrate and the circuit body, and the solder resist layer is formed after curing. The solder resist ink itself is easy to cause uneven color due to batch problems, and the diluent will change the color of the solder resist ink after adding the solder resist ink, making the color of the solder resist ink more difficult to control and adjust. Furthermore, because the process flow of screen printing and curing the solder mask ink is longer and takes a long time, and the diluent in the solder mask ink is volatile, the color of the solder mask ink will gradually darken when the diluent volatilizes. Furthermore, it is difficult to control the color of the solder resist ink after curing, that is, it is difficult to control the color of the solder resist layer. When light shines on the solder resist layer, the color consistency reflected by the solder resist layer is poor, and when the light shines through the solder resist layer on the substrate, the color of the substrate will further affect the color of the solder resist layer, resulting in The color consistency of the circuit board is poor. In this application, the photo-curable ink is manufactured by mass mixing, and the mixed photo-curable ink does not contain volatile substances, so it has good stability, and the photo-curable ink is a mature printing ink. Its configuration ratio and color have strict test standards, so the color of each batch of light-curing ink is relatively uniform. When printing the light-curing ink on the solder mask, the printing component and the light irradiation component of the light-curing ink printing equipment are integrated on the same device, and the light-curing ink is immediately cured after printing, so the production time is short and the light curing is easy to control The color consistency of the ink. In other words, it is easier to control the color of the first ultraviolet curable ink layer to be white, and control the second ultraviolet curable ink layer to be set to the required color as required, so that the ink layer can better maintain color consistency.

In one embodiment, the ink layer is solder resist ink. Although the color of the solder resist ink is difficult to control, since the inner layer of the solder resist ink is provided with an optical barrier layer, the reflected light of the substrate is prevented from being projected on the ink layer. Therefore, compared to the solder resist layer provided on the substrate in the prior art, even if the raw material of the ink layer of the present application is solder resist ink, it can still have better color consistency than the prior art.

In order to realize that the optical barrier layer is used to reflect white light, in one embodiment, the white colorant in the raw material of the optical barrier layer accounts for 0.3%-50% of the total mass of the raw material. Specifically, the optical barrier layer includes a transparent resin, a white colorant, a photosensitizer, and a diluent, wherein the white colorant accounts for 0.3% to 50% of the total mass of the raw material, so that the color of the optical barrier layer is white. And can reflect white light. The remaining components can be blended as needed, and the specific proportions of the remaining components can be blended according to the prior art, and this embodiment will not be redundant.

In order to realize that the optical barrier layer reflects white light, in one of the embodiments, the thickness of the optical barrier layer is 0.01 mm to 0.2 mm. When the optical barrier layer is set to this thickness, it can reflect white light, and when the thickness is in this range, the cost is If it is lower, the influence on the welding of the lamp beads is also small, so as to avoid hindering the welding of the lamp beads.

In order to achieve consistency of ink color after the display screen is off, in one of the embodiments, the color of the ink layer is black or gray. When the ink layer is set to black or gray, after the display screen is closed, light is irradiated on the ink layer, and the ink layer appears black or gray, so as to achieve the consistency of ink color after the display screen is closed.

In one of the embodiments, as shown in FIG. 1 and FIG. 2, a display screen 10 is also provided, which includes lamp beads 120 and the circuit board described in any of the above embodiments, and the lamp beads 120 are arranged on the On the circuit board, and the lamp beads 120 are connected to the circuit layer 200. In this embodiment, a driving component 110 is provided on the side of the substrate 100 facing away from the lamp bead 120, and the driving component is connected to the lamp bead 120 through the circuit layer, and the driving component 110 is used to drive the lamp bead 120. The lamp beads 120 emit light.

Specifically, the substrate is provided with a via hole, the side wall of the via hole is provided with hole copper, and the circuit layer is connected with the driving component through the hole copper, thereby realizing the connection between the driving component and the lamp bead , And drive the lamp beads to emit light.

In the above-mentioned display screen 10, when the lamp beads 120 are extinguished, the optical barrier layer 300 can reflect white light, thereby avoiding reflecting the color of the substrate 100 on the circuit board, thereby maintaining the color consistency of the ink layer 400, and ensuring that the lamp beads 120 are extinguished. The color consistency of the display screen 10.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, All should be considered as the scope of this specification.

The above-mentioned embodiments only express a few implementation modes of the present application, and their description is relatively specific and detailed, but they should not be understood as a limitation on the scope of the patent application. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can be made, and these all fall within the protection scope of this application. Therefore, the scope of protection of the patent of this application shall be subject to the appended claims.

Claims

A circuit board, comprising a substrate and a circuit layer, the circuit layer is arranged on the substrate, the substrate is provided with an optical barrier layer on the side facing the circuit layer, and the raw material of the optical barrier layer It includes a white color material, and an ink layer is provided on the side of the optical barrier layer away from the substrate and the circuit layer.
The circuit board of claim 1, further comprising a solder resist layer, the circuit layer includes a circuit body and a plurality of pads, and the circuit body is connected to each of the pads, and the solder resist The layer is disposed on the circuit body and the substrate, the solder resist layer is provided with openings, the openings are aligned with each of the pads, and the optical barrier layer is disposed on the surface of the solder resist layer.
The circuit board according to claim 1, wherein the optical barrier layer is disposed on the side of the substrate facing the circuit layer by printing.
The circuit board according to claim 1, wherein the raw material of the optical barrier layer is at least one of photocurable ink, thermosetting ink and volatile ink.
The circuit board according to claim 1, wherein the white pigment in the raw material of the optical barrier layer accounts for 0.3%-50% of the total mass of the raw material.
The circuit board according to claim 1, wherein the thickness of the optical barrier layer is 0.01 mm to 0.2 mm.
The circuit board according to claim 1, wherein the raw material of the ink layer is at least one of photocurable ink, thermosetting ink and volatile ink.
The circuit board according to claim 1, wherein the raw material of the optical barrier layer is ultraviolet curable ink.
The circuit board according to claim 1, wherein the color of the ink layer is black or gray.
The circuit board according to claim 1, wherein the ink layer is disposed on the optical barrier layer by printing.
The circuit board according to claim 1, wherein the optical barrier layer covers a position of the substrate where the circuit layer is not provided.
A display screen, including lamp beads, is characterized in that it also includes a circuit board, the circuit board includes a substrate and a circuit layer, the circuit layer is disposed on the substrate, and the substrate is disposed toward the side of the circuit layer There is an optical barrier layer, the raw material of the optical barrier layer includes a white colorant, an ink layer is provided on the side of the optical barrier layer away from the substrate and the circuit layer, and the lamp beads are arranged on the circuit board , And the lamp beads are connected to the circuit layer.
The display screen of claim 12, further comprising a solder resist layer, the circuit layer includes a circuit body and a plurality of pads, and the circuit body is connected to each of the pads, and the solder resist The layer is disposed on the circuit body and the substrate, the solder resist layer is provided with openings, the openings are aligned with each of the pads, and the optical barrier layer is disposed on the surface of the solder resist layer.
The display screen according to claim 12, wherein the optical barrier layer is disposed on the side of the substrate facing the circuit layer by printing.
The display screen of claim 12, wherein the raw material of the optical barrier layer is at least one of photocurable ink, thermosetting ink and volatile ink.
The display screen according to claim 12, wherein the white colorant in the raw materials of the optical barrier layer accounts for 0.3%-50% of the total mass of the raw materials.
The display screen of claim 12, wherein the optical barrier layer has a thickness of 0.01 mm to 0.2 mm.
The display screen according to claim 12, wherein the raw material of the ink layer is at least one of photocurable ink, thermosetting ink and volatile ink.
The display screen of claim 12, wherein the color of the ink layer is black or gray.
The display screen of claim 12, wherein the ink layer is disposed on the optical barrier layer by printing.