Integrated functional layer for light-emitting module, preparation method of integrated functional layer and light-emitting module

Abstract

The invention discloses an integrated functional layer for a light-emitting module, a preparation method of the integrated functional layer and the light-emitting module, a conductive circuit layer and an optical functional layer are integrated on the same insulating base material, and the optical functional layer at least comprises a reflection area used for improving the light utilization rate and a shading area used for preventing light leakage. And the reflection region and the shading region are positioned on the same structural layer. A layer of integrated functional layer structure is used for replacing a traditional independent layered five structure, the framework of the light-emitting module is fundamentally simplified, the types of materials for manufacturing the light-emitting module are reduced, the production cost is reduced, complex procedures such as alignment and curing in the machining process can be reduced, the production period is shortened, and the production efficiency is improved. And meanwhile, the light-emitting module can meet the diversified requirements of thin and light-weight products.

Description

Technical Field

[0001] This invention relates to the field of flexible printed circuit board technology, specifically to an integrated functional layer for a light-emitting module, its preparation method, and the light-emitting module itself. Background Technology

[0002] In light-emitting devices such as LCD backlight modules (BLU), advertising light boxes, and various signs, three core functional components are typically involved: a flexible circuit board (FPC) for carrying and electrically connecting to light-emitting diodes (LEDs), a reflective film for efficiently reflecting light back to the light-emitting area to enhance brightness, and a light-shielding film for preventing light leakage from non-display surfaces and ensuring visual contrast or a clean appearance.

[0003] Currently, mainstream technical solutions typically employ stacking and gluing of these functional components as independent physical layers. However, this traditional approach has the following significant drawbacks: the use of multiple independent components increases the variety and cost of materials; its manufacturing process involves complex steps such as FPC processing, multi-layer lamination, and multiple alignment and curing processes, resulting in a long production cycle; furthermore, the multi-layer stacked structure inevitably increases the overall thickness of the module, making it difficult to meet the increasingly urgent demand for thinner and lighter designs in end products.

[0004] Therefore, it is necessary to improve upon the aforementioned deficiencies. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an integrated functional layer for a light-emitting module, a method for preparing the same, and a light-emitting module.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: In a first aspect, the present invention provides an integrated functional layer for a light-emitting module, wherein a conductive circuit layer and an optical functional layer are integrated on the same insulating substrate, the optical functional layer including at least a reflective region for improving light utilization and a light-shielding region for preventing light leakage, and the reflective region and the light-shielding region are located in the same structural layer.

[0007] The beneficial effects of this invention are: by integrating the traditionally separately layered FPC circuit board layer structure, reflective layer structure, and light-shielding layer structure into a single structural layer structure, it reduces the number of adhesive layers used to bond the reflective layer structure and the light-shielding layer structure, as well as the number of separately installed reflective layer structures and light-shielding layer structures. In other words, this invention integrates the traditionally separately layered FPC circuit board layer structure, reflective layer (with light-reflecting function), two adhesive layers for bonding, and light-shielding layer (with light-shielding function) into a single integrated functional layer structure. This invention fundamentally simplifies the architecture of the light-emitting module. The integrated functional layer can fulfill the functions of conductive circuitry, light reflection, and light shielding. Compared to traditional four-layer light-emitting modules, this invention simplifies the light-emitting module structure, reduces the types of materials used in manufacturing the module, and lowers production costs. Furthermore, by simplifying the light-emitting module structure, complex processes such as alignment and curing can be reduced during FPC processing, shortening the production cycle. Additionally, the simplified structure also reduces the overall thickness of the light-emitting module, allowing it to meet the diverse needs of thinner and lighter products.

[0008] Based on the above technical solution, the present invention can be further improved as follows.

[0009] Furthermore, the thickness of the insulating substrate ranges from 5 μm to 2000 μm.

[0010] The beneficial effect of adopting the above-mentioned further solution is that by using an insulating substrate of 5μm to 2000μm, the light-emitting module can meet the requirements of both ultra-thin and ultra-thick structures.

[0011] Furthermore, the insulating substrate is made of any one of polyethylene terephthalate, polyvinyl chloride, polyimide, and epoxy glass cloth laminate.

[0012] Furthermore, the conductive circuit layer is formed by curing a printable conductive paste, the conductive paste comprising silver, copper, or an alloy thereof.

[0013] The beneficial effects of adopting the above-mentioned further solution are as follows: This invention uses printable conductive paste, which differs from the traditional copper etching process of FPC, allowing the invention to integrate separately layered reflective layer structures and light-shielding layer structures onto the same structural layer. Simultaneously, the use of silver paste and copper paste improves the conductivity of the conductive circuit layer.

[0014] Furthermore, the reflective area is composed of a white high-reflectivity ink layer coated on the insulating substrate, and the light-shielding area is composed of a dark-colored high-shielding ink layer coated on the insulating substrate.

[0015] The beneficial effect of adopting the above-mentioned further solution is that by using printing ink to form the reflective and light-shielding areas of the optical functional layer, the compatibility between the optical functional layer and the printed conductive circuit layer can be effectively improved, realizing true "integrated printing" manufacturing.

[0016] Furthermore, the white high-reflectivity ink layer covers the conductive circuit layer, and only exposes the pads and connection terminals used for electrical connection in the conductive circuit area.

[0017] The beneficial effect of adopting the above-mentioned further solution is that the reflective area formed by the white high reflectivity ink layer covers the conductive circuit layer, and the white high reflectivity ink layer exposes the pads and connection terminals used for electrical connection, so that the reflective area can not only satisfy the function of reflecting light, but also provide insulation protection and prevent oxidation of the conductive circuit layer below.

[0018] Furthermore, the reflective area and the light-shielding area are respectively disposed on two opposite surfaces of the insulating substrate.

[0019] The beneficial effect of adopting the above-mentioned further solution is that by setting the reflective area and the light-shielding area on the front and back sides of the single-layer insulating substrate film, the functions of reflecting light and shielding light can be effectively set on the two sides of the film respectively, forming a clear physical isolation, avoiding light crosstalk, and achieving the optimal form of optical performance.

[0020] In a second aspect, the present invention also provides a light-emitting module, including a light guide plate, a light-emitting element disposed on the light-incident side of the light guide plate, and the integrated functional layer for the light-emitting module in the first aspect; The light-emitting element is electrically connected to the conductive circuit layer region of the integrated functional layer, and the optical functional layer of the integrated functional layer is correspondingly disposed on the bottom surface and / or side surface of the light guide plate.

[0021] The beneficial effects of this invention are as follows: This invention fundamentally improves the structure of the light-emitting module by replacing the traditional five-layer structure of the FPC circuit board layer, reflective layer, light-shielding layer, and two separate adhesive layers used for bonding with an integrated functional layer. This simplifies the overall structural architecture of the light-emitting module. The integrated functional layer can fulfill the functions of conductive circuitry, light reflection, and light shielding. This integrated functional layer structure reduces the types of materials used in manufacturing the light-emitting module and lowers production costs. In addition, it reduces complex processes such as alignment and curing during FPC processing, shortening the production cycle. Furthermore, it reduces the overall thickness of the light-emitting module, enabling it to meet the diverse needs of thin and lightweight products.

[0022] Based on the above technical solution, the present invention can be further improved as follows.

[0023] Furthermore, a light-shielding layer and a dust-proof layer are sequentially arranged above the light guide plate from bottom to top. The light-shielding layer is adhesively connected to the light guide plate, and the light guide plate is adhesively connected to the light-emitting element.

[0024] The beneficial effects of adopting the above-mentioned further solution are: by sequentially placing the dustproof layer, light-shielding layer, light guide plate and light-emitting element on top of the integrated functional layer to form a 5-layer structure, the underlying structure of the light-emitting module of the present invention is fundamentally simplified compared to the traditional 7-layer structure of the light-emitting module, thereby making the light-emitting module of the present invention thinner, lighter and reducing the number of production steps.

[0025] Thirdly, the present invention also provides a method for preparing an integrated functional layer for a light-emitting module, comprising the following steps: S1: Provides insulating substrate; S2: Print a conductive paste pattern on the first surface of the insulating substrate and cure it to form a conductive circuit layer area; S3: On the first surface of the insulating substrate, optical ink is printed to cover the conductive line layer region to form at least a portion of the reflective region of the optical functional layer and to precisely expose the pads and connection terminals in the conductive line layer region. S4: Print light-shielding ink on the second surface of the insulating substrate opposite to the first surface to form the light-shielding area of ​​the optical functional area.

[0026] The beneficial effects of this invention are: by printing conductive circuit layer structure and reflective and light-shielding areas of optical functional layer on insulating substrate, compared with the complex steps of multiple bonding, alignment and pressing required by the separately layered FPC circuit board layer structure, reflective layer structure and light-shielding layer structure in traditional light-emitting modules, the preparation method of this invention has a simpler process flow and higher production efficiency. Attached Figure Description

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0028] Figure 1 This is a schematic diagram of the structure of the light-emitting module in this invention; Figure 2 This is a schematic diagram of the integrated functional layer of the light-emitting module in this invention; Figure 3 This is a flowchart of the method for preparing the integrated functional layer of the light-emitting module in this invention.

[0029] The attached diagram lists the components represented by each number as follows: 10. Conductive circuit layer; 20. Optical functional layer; 21. Reflective area; 211. White high reflectivity ink layer; 22. Light-shielding area; 221. Dark high light-shielding ink layer; 30. Insulating substrate; 40. Light guide plate; 50. Light-emitting element; 60. Light-shielding layer; 70. Dustproof layer. Detailed Implementation

[0030] The following will clearly and completely describe the concept, specific structure, and technical effects of the present invention in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. Furthermore, all connections / linkages involved in the patent do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this invention can be combined interactively without contradicting each other.

[0031] Example 1 refer to Figures 1-2 The present invention provides an integrated functional layer for a light-emitting module, wherein a conductive circuit layer 10 and an optical functional layer 20 are integrated on the same insulating substrate 30. The optical functional layer 20 includes at least a reflective region 21 for improving light utilization and a light-shielding region 22 for preventing light leakage, and the reflective region 21 and the light-shielding region 22 are located in the same structural layer.

[0032] In this embodiment, reference Figure 2 This embodiment provides an integrated functional layer for a light-emitting module. Its core lies in integrating the five layers—the FPC circuit board layer, reflective layer, light-shielding layer 60, and adhesive layer for bonding—that exist independently in a traditional light-emitting module into a single layered structure. Specifically, a conductive circuit layer 10 and an optical functional layer 20 are simultaneously integrated onto an insulating substrate 30 using a printing process. This optical functional layer 20 includes a reflective region 21 for reflecting light and a light-shielding region 22 for preventing light leakage, all within the same structural layer. The reflective region 21 is composed of a white high-reflectivity ink layer 211, and the light-shielding region 22 is composed of a black high-shielding ink layer. In this embodiment, the reflective region 21 and the light-shielding region 22 are located on opposite sides of the insulating substrate 30, but under the concept of the same structural layer, the reflective region 21 and the light-shielding region 22 together constitute the optical functional layer 20 integrated into the substrate, rather than an independent physical film layer.

[0033] It should be explained that in this embodiment, the insulating substrate 30 is a white polyethylene terephthalate (PET) film with a thickness of 100 μm, which has good flatness, insulation and mechanical strength.

[0034] The conductive circuit layer 10 is formed by printing silver paste (silver content ≥65%) onto the first surface (upper surface) of the insulating substrate 30 using a 300-mesh screen. The printed pattern includes multiple pads for soldering the light-emitting elements 50LEDs, traces connecting the pads, and gold fingers for connecting to an external power supply. After printing, the substrate is placed in a hot air circulating oven and cured at 130°C for 10 minutes to form the conductive circuit layer 10 with a sheet resistance of less than 50 mΩ / □.

[0035] The reflective area 21 is formed by screen printing a layer of white high-reflectivity UV ink using a 350-mesh screen above the cured conductive circuit layer 10. This ink uses titanium dioxide (TiO2) as a reflective filler and has a reflectivity greater than 92% after curing. The pattern printed with the white high-reflectivity UV ink is designed to cover all circuit areas except for the solder pads and gold fingers, achieving both protection and reflection. Immediately after printing, it is cured by irradiation with a UV lamp (wavelength 365nm, light intensity 80mW / cm²).

[0036] To form the light-shielding region 22, the insulating substrate 30, which forms the emission region, is flipped over, and a layer of black light-shielding ink (optical density OD>3) is screen-printed on its second surface (lower surface, opposite to the first surface). After printing, it is heat-cured at 90°C for 20 minutes.

[0037] It should be noted that the integrated functional layer manufactured in this embodiment successfully simplifies the traditional five-layer structure of FPC, reflective film, light-shielding film, and two adhesive layers into a single-layer structure. Calculations show that the number of material types is reduced by approximately 60%, resulting in lower direct material costs. In production, the multi-layer cutting, alignment, and bonding processes are eliminated, shortening the production cycle from 5-7 days in the traditional approach to less than 1 day. Simultaneously, the integrated structure eliminates the reflective film, light-shielding film, and adhesive layers, significantly reducing the overall product thickness. This facilitates the design of thinner end products, fundamentally solving the problems of high material costs, complex processes, and thick products in traditional light-emitting module manufacturing.

[0038] The beneficial effects of this invention are: by integrating the separately layered FPC circuit board layer structure, reflective layer structure, and light-shielding layer 60 structure into a single structural layer, the number of adhesive layers used to bond the reflective layer structure and the light-shielding layer 60 structure, as well as the number of separately layered reflective layer structure and light-shielding layer 60 structure, is reduced. In other words, this invention integrates the traditionally separately layered FPC circuit board layer structure, reflective layer (with light-reflecting function), two adhesive layers for bonding, and light-shielding layer 60 into a single integrated functional layer structure. This invention fundamentally simplifies the architecture of the light-emitting module. The integrated functional layer can fulfill the functions of conductive circuitry, light reflection, and light shielding. Compared to traditional four-layer light-emitting modules, this invention simplifies the light-emitting module structure, reduces the types of materials used in manufacturing the module, and lowers production costs. Furthermore, by simplifying the light-emitting module structure, complex processes such as alignment and curing can be reduced during FPC processing, shortening the production cycle. Additionally, the simplified structure also reduces the overall thickness of the light-emitting module, allowing it to meet the diverse needs of thinner and lighter products.

[0039] Preferred, Reference Figure 2 The thickness of the insulating substrate 30 ranges from 5 μm to 2000 μm.

[0040] In this embodiment, when applied to the backlight of an ultrathin flexible display, the insulating substrate 30 can be a transparent polyimide (PI) film with a thickness of 8 μm. Specifically, on this ultrathin substrate, the conductive circuit layer 10 pattern is printed using nano-silver conductive ink (curing temperature ≤120℃) and combined with low-temperature curing optical ink to prepare a flexible integrated functional layer with a total thickness of less than 30 μm, which meets the requirements of foldable devices for extreme thinness.

[0041] In some embodiments, when applied to large-area advertising light boxes that require structural support and heat dissipation, the insulating substrate 30 can be made of FR-4 epoxy glass cloth laminate with a thickness of 1.5mm. Specifically, the conductive lines can be printed with thick film copper paste to carry large currents, and the optical inks are selected from outdoor models with stronger weather resistance. This integrated functional layer structure combines the functions of a circuit board, a reflector, and a light shield, and has a robust structure.

[0042] It should be explained that the present invention, by adapting to various insulating substrates 30 with thicknesses ranging from 5μm to 2000μm, can achieve both the extreme thinness of the product and meet the structural strength requirements in specific scenarios, thus expanding the application boundaries of the technology.

[0043] By using an insulating substrate 30 ranging from 5μm to 2000μm, the integrated functional layer can meet the requirements of both ultra-thin light-emitting module structures and ultra-thick light-emitting module structures.

[0044] Preferred, Reference Figure 2 The insulating substrate 30 is made of any one of polyethylene terephthalate, polyvinyl chloride, polyimide, and epoxy glass cloth laminate.

[0045] In this embodiment, the insulating substrate 30 can also be made of polyvinyl chloride (PVC), polyimide (PI), or epoxy glass cloth laminate (FR4). Specifically, when using a polyvinyl chloride (PVC) substrate for the insulating substrate 30, a 150μm thick white PVC rigid sheet can be selected as the insulating substrate 30. It should be understood that PVC is inexpensive and suitable for cost-sensitive mid-to-low-end luminous signage products. More specifically, by using PVC-specific conductive silver paste and ink that match the polyvinyl chloride (PVC) substrate and curing them in stages at 100°C, a reliable integrated functional layer can be formed.

[0046] In some embodiments, due to the physical properties of high temperature resistance and dimensional stability of polyimide (PI) substrates, they can be used in high-end display products that require high-temperature SMT soldering processes or operate in high-temperature environments.

[0047] In some embodiments, epoxy glass cloth laminate (FR4) substrates, due to their rigidity and the need for good heat dissipation and support, can be used to replace the traditional “aluminum-based circuit board + reflective film” solution.

[0048] Preferred, Reference Figure 2 The conductive circuit layer 10 is formed by curing a printable conductive paste, the conductive paste comprising silver, copper or their alloys.

[0049] In this embodiment, the conductive paste is a low-temperature curing copper paste with approximately 70% copper particles and 30% organic carrier. Specifically, a 400-mesh polyester screen is used to print the conductive circuit layer 10 pattern on a 100μm thick white PET substrate 110. The printing pattern accuracy is controlled by screen tension and squeegee pressure, achieving a line width / spacing of 100μm / 100μm. The printed substrate is then placed in an infrared tunnel oven and cured at a peak temperature of 160°C for 5 minutes. After curing, the organic solvents in the copper paste evaporate, and the metal particles sinter to form a dense conductive network, with the circuit resistance meeting the requirements for driving LEDs.

[0050] It is important to understand that the copper paste printing process reduces the number of process steps by more than 50% compared to the traditional subtractive method of FPC (copper clad laminate-exposure-etching), and eliminates chemical etching waste, making it more environmentally friendly. The use of silver or copper paste ensures good conductivity, allowing this invention to simplify the structure without sacrificing electrical performance, which is a key prerequisite for achieving "circuit and optical function integration".

[0051] This invention uses printable conductive paste, unlike the traditional copper etching process of FPC, allowing the integration of separately layered reflective layer structures and light-shielding layer 60 structures onto a single structural layer. Simultaneously, the use of silver and copper paste improves the conductivity of the conductive circuit layer 10.

[0052] Preferred, Reference Figure 2 The reflective area 21 is composed of a white high-reflectivity ink layer 211 coated on the insulating substrate 30, and the light-shielding area 22 is composed of a dark-colored high-shielding ink layer 221 coated on the insulating substrate 30.

[0053] In this embodiment, the white high-reflectivity ink layer 211 used to coat the reflective area 21 can be a UV-curable coating, whose main components include 50% acrylic resin (base material), 45% rutile titanium dioxide (particle size 0.2-0.3μm, reflective filler), 5% photoinitiator, and other additives. After curing, the UV-curable coating has a white surface and a measured reflectivity of over 95% for 450nm blue light (a common LED light source). Additionally, the dark-colored high-shielding ink layer 221 used to coat the light-shielding area 22 can be a black thermosetting epoxy ink with a carbon black content as high as 25% and added anti-settling additives. After curing, the film layer is dense, with an optical density (OD value) exceeding 4.0, effectively absorbing stray light leaking from the light guide plate 40.

[0054] It should be explained that the biggest advantage of using printing ink to form the optical functional layer 20 is its high compatibility with the process of printing conductive circuits. Both can be processed sequentially through similar processes such as screen printing and spraying, achieving "integrated printing" manufacturing on the same production line, which greatly simplifies the production process and reduces equipment investment and production changeover costs.

[0055] By using printing ink to form the reflective area 21 and the light-shielding area 22 of the optical functional layer 20, the compatibility between the optical functional layer 20 and the printed conductive circuit layer 10 can be effectively improved, achieving true "integrated printing" manufacturing.

[0056] Further reference Figure 2 The white high-reflectivity ink layer 211 covers the conductive circuit layer 10 and exposes only the pads and connection terminals in the conductive circuit area for electrical connection.

[0057] In this embodiment, the reflective area 21 formed by the white high-reflectivity ink layer 211 covers the conductive circuit layer 10. Specifically, after the conductive circuit layer 10 is printed and cured, a high-precision CCD vision alignment system is used to print the white high-reflectivity ink a second time. The system first identifies the alignment marks on the circuit layer, and then controls the screen movement to ensure that the printed pattern of the white high-reflectivity ink can accurately cover all traces, leaving only a circular pad with a diameter of 1.0 mm and a long strip of gold finger area.

[0058] Additionally, after the white high-reflectivity ink layer 211 completely covered the circuit, the insulation resistance between any two adjacent traces was measured using a multimeter on the high resistance setting. The value was greater than 10^9 Ω, indicating that the ink layer provided good insulation protection. Furthermore, after placing the sample in an 85℃ / 85%RH environment for 500 hours, slight oxidation was observed in the pad area, but the resistance change rate of the ink-covered circuit was less than 2%, proving that the ink layer effectively prevented electrochemical corrosion of the circuit in humid environments.

[0059] It should be understood that the white high-reflectivity ink layer 211 in this embodiment not only provides optical reflection but also serves as a solder resist layer and a protective layer. This design eliminates the need for a separate solder resist layer fabrication process on traditional FPCs, achieving "multi-purpose use of one material," further simplifying the structure and process, and improving the environmental reliability of the product.

[0060] The white high-reflectivity ink layer 211 forms a reflective area 21 that covers the conductive circuit layer 10. The white high-reflectivity ink layer 211 exposes the pads and connection terminals used for electrical connection, so that the reflective area 21 can not only reflect light, but also provide insulation protection and prevent oxidation of the conductive circuit layer 10 below.

[0061] Preferred, Reference Figure 2 The reflective area 21 and the light-shielding area 22 are respectively disposed on two opposite surfaces of the insulating substrate 30.

[0062] In this embodiment, the reflective region 21 is disposed on the first surface (upper surface) of the insulating substrate 30, while the light-shielding region 22 is disposed on the opposite second surface (lower surface). Specifically, when the integrated functional layer is applied to the backlight module, its upper surface (reflective region 21) faces the light guide plate 40, efficiently reflecting downward-leaking light back; its lower surface (light-shielding region 22) faces away from the external environment, absorbing any residual light transmitted through the substrate. The reflective region 21 and the light-shielding region 22 are physically isolated by the insulating substrate 30, completely avoiding mutual interference (optical crosstalk) between reflected light and light-shielding function, ensuring the highest optical efficiency (high brightness) and the lowest light leakage (high contrast).

[0063] By placing the reflective area 21 and the light-shielding area 22 on the front and back sides of the single-layer insulating substrate 30 film, the functions of reflecting light and shielding light can be effectively placed on the two sides of the film respectively, forming a clear physical isolation, avoiding light crosstalk, and achieving the optimal form of optical performance.

[0064] Example 2 refer to Figures 1-2 Based on Embodiment 1, the present invention also provides a light-emitting module, including a light guide plate 40, a light-emitting element 50 disposed on the light-incident side of the light guide plate 40, and an integrated functional layer for the light-emitting module as described in the first aspect; the light-emitting element 50 is electrically connected to the conductive line layer 10 region of the integrated functional layer, and the optical functional layer 20 of the integrated functional layer is correspondingly disposed on the bottom surface and / or side surface of the light guide plate 40.

[0065] In this embodiment, the light-emitting module includes, from top to bottom: a dustproof film (or a brightness enhancement film), an upper light-shielding tape, optical adhesive, a light guide plate 40, a photoelectric element LED, a pressure-sensitive adhesive layer, and the integrated functional layer described in this invention. Specifically, the photoelectric element LED is soldered onto the pads on the upper surface of the integrated functional layer using an SMT process. A layer of transparent pressure-sensitive adhesive with a thickness of 0.05 mm is coated on the upper surface of the integrated functional layer (on the white high-reflectivity ink layer 211). The light-incident side of the light guide plate 40 is aligned with the photoelectric element LED, and then the entire integrated functional layer is flatly adhered to the bottom of the light guide plate 40 using the pressure-sensitive adhesive layer. In this light-emitting module, the integrated functional layer can simultaneously power the photoelectric element LED through its conductive circuit layer 10 (replacing the FPC); simultaneously, it reflects light from the bottom of the light guide plate 40 through the upper surface of the white high-reflectivity ink layer 211 in its reflective area 21 (replacing the reflective film); and it can also prevent light from leaking downwards through the lower surface of the dark high-shield ink layer 221 in its light-shielding area 22 (replacing the light-shielding film).

[0066] It should be explained that the integrated functional layer of this invention can be directly used as a core component to assemble high-performance light-emitting modules. The overall thickness of this module is reduced by approximately 30%-40% compared to traditional structures, resulting in lighter weight. Furthermore, due to the robust and integrated underlying structure, the assembly yield is improved.

[0067] The beneficial effects of this invention are as follows: This invention fundamentally improves the structure of the light-emitting module by replacing the traditional five-layer structure of the FPC circuit board layer, reflective layer, light-shielding layer 60, and two separate adhesive layers for bonding with an integrated functional layer. This simplifies the overall structural architecture of the light-emitting module. The integrated functional layer can fulfill the functions of conductive circuitry, light reflection, and light shielding. This allows the invention to reduce the types of materials used in manufacturing the light-emitting module and lower production costs. In addition, it reduces complex processes such as alignment and curing during FPC processing, shortening the production cycle. Furthermore, it reduces the overall thickness of the light-emitting module, enabling it to meet the diverse needs of thin and lightweight products.

[0068] Preferred, Reference Figure 1 A light-shielding layer 60 and a dust-proof layer 70 are arranged sequentially above the light guide plate 40 from bottom to top. The light-shielding layer 60 is glued to the light guide plate 40, and the light guide plate 40 is glued to the light-emitting element 50.

[0069] In this embodiment, above the light guide plate 40, a layer of light-shielding tape is sequentially bonded with an optical adhesive layer to prevent light leakage at the edges, and a dustproof film is then placed on top to prevent dust and diffuse light. In other words, the upper layer of the light-emitting module is a four-layer structure consisting of a dustproof layer 70, a light-shielding layer 60, a light guide plate 40, and a light-emitting element 50, which are connected to each other by adhesive. The lower layer is the integrated functional layer of this invention.

[0070] It should be explained that traditional side-lit backlight modules typically have a structure of 7 or more layers, including a dustproof film, upper light-shielding tape, light guide plate 40, LED, FPC, reflective film, and lower light-shielding film. This invention integrates the lower FPC, reflective film, lower light-shielding film, and adhesive layer into a single layer, significantly reducing the total number of layers and greatly decreasing structural complexity. This fundamental simplification of the light-emitting module architecture results in a thinner and more cost-effective module structure, while also reducing potential tolerance accumulation and defect rates during assembly, thus optimizing the overall manufacturability and reliability of the product.

[0071] By sequentially placing the dustproof layer 70, the light-shielding layer 60, the light guide plate 40, and the light-emitting element 50 on top of the integrated functional layer, a structure of 5 individually layered layers is formed. Compared with the traditional 7-layer layered structure of the light-emitting module, the underlying structure of the light-emitting module of the present invention is fundamentally simplified, thereby making the light-emitting module of the present invention thinner, lighter, and reducing the number of production steps.

[0072] Example 3 refer to Figure 3 Based on Embodiment 1 and / or Embodiment 2, the present invention also provides a method for preparing an integrated functional layer for a light-emitting module, comprising the following steps: S1: Provide insulating substrate 30; Specifically, we provide rolls of white PET substrate film, 500 mm wide and 125 μm thick. After unwinding, the film undergoes a corona treatment process to achieve a surface tension of over 50 dynes / cm.

[0073] S2: A conductive paste pattern is printed on the first surface of the insulating substrate 30 and cured to form the conductive line layer 10 region. Specifically, the insulating substrate 30 enters the first fully automatic CCD alignment screen printing station. After the silver paste conductive circuit layer 10 is printed, it immediately enters a three-temperature zone hot air curing oven with a length of 8 meters (temperature setting: 120℃-140℃-130℃), with a speed of 2 meters / minute, to complete the circuit curing.

[0074] S3: On the first surface of the insulating substrate 30, optical ink is printed to cover the area of ​​the conductive line layer 10 to form at least a portion of the reflective area 21 of the optical functional layer 20 and to precisely expose the pads and connection terminals in the area of ​​the conductive line layer 10. Specifically, the insulating substrate 30 enters the second CCD alignment printing station to be printed with white high-reflectivity UV ink. After printing, it passes through a high-intensity UV LED curing station (wavelength 395nm) and is cured within 0.5 seconds.

[0075] S4: Print light-shielding ink on the second surface of the insulating substrate 30 opposite to the first surface to form the light-shielding area 22 of the optical functional area.

[0076] Specifically, the insulating substrate 30 is rotated 180 degrees by guide rollers. It then enters the third printing station to be printed with black opaque ink. Subsequently, it enters the second stage hot air curing oven (90℃) at a speed of 2 meters per minute to complete the final curing.

[0077] The beneficial effects of the present invention are as follows: By printing the conductive circuit layer 10 structure and the reflective region 21 and light-shielding region 22 structure of the optical functional layer 20 on the insulating substrate 30, compared with the complex steps of multiple bonding, alignment and pressing required by the separately layered FPC circuit board layer structure, reflective layer structure and light-shielding layer 60 structure in the traditional light-emitting module, the preparation method of the present invention has a simpler process flow and higher production efficiency.

[0078] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. An integrated functional layer for a light-emitting module, characterized in that, A conductive circuit layer and an optical functional layer are integrated on the same insulating substrate. The optical functional layer includes at least a reflective region for improving light utilization and a light-shielding region for preventing light leakage, and the reflective region and the light-shielding region are located in the same structural layer.

2. The integrated functional layer for a light-emitting module according to claim 1, characterized in that, The thickness of the insulating substrate ranges from 5 μm to 2000 μm.

3. The integrated functional layer for a light-emitting module according to claim 1, characterized in that, The insulating substrate is made of any one of polyethylene terephthalate, polyvinyl chloride, polyimide, and epoxy glass cloth laminate.

4. The integrated functional layer for a light-emitting module according to claim 1, characterized in that, The conductive circuit layer is formed by curing a printable conductive paste, the conductive paste comprising silver, copper, or an alloy thereof.

5. The integrated functional layer for a light-emitting module according to claim 1, characterized in that, The reflective area is composed of a white, high-reflectivity ink layer coated on the insulating substrate, and the light-shielding area is composed of a dark-colored, high-shielding ink layer coated on the insulating substrate.

6. The integrated functional layer for a light-emitting module according to claim 5, characterized in that, The white, high-reflectivity ink layer covers the conductive circuit layer and exposes only the pads and connection terminals used for electrical connection in the conductive circuit area.

7. The integrated functional layer for a light-emitting module according to claim 1 or 5, characterized in that, The reflective area and the light-shielding area are respectively disposed on two opposite surfaces of the insulating substrate.

8. A light-emitting module, characterized in that, It includes a light guide plate, a light-emitting element disposed on the light-incident side of the light guide plate, and an integrated functional layer according to any one of claims 1 to 7; The light-emitting element is electrically connected to the conductive circuit layer region of the integrated functional layer, and the optical functional layer of the integrated functional layer is correspondingly disposed on the bottom surface and / or side surface of the light guide plate.

9. The light-emitting module according to claim 8, characterized in that, A light-shielding layer and a dust-proof layer are arranged sequentially above the light guide plate from bottom to top. The light-shielding layer is glued to the light guide plate, and the light guide plate is glued to the light-emitting element.

10. A method for preparing an integrated functional layer for a light-emitting module as described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1: Provides insulating substrate; S2: Print a conductive paste pattern on the first surface of the insulating substrate and cure it to form a conductive circuit layer area; S3: On the first surface of the insulating substrate, optical ink is printed to cover the conductive line layer region to form at least a portion of the reflective region of the optical functional layer and to precisely expose the pads and connection terminals in the conductive line layer region. S4: Print light-shielding ink on the second surface of the insulating substrate opposite to the first surface to form the light-shielding area of ​​the optical functional area.

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