LED lamp strip

Abstract

The LED lamp strip comprises LED lamp beads, a base material layer, a conductive layer and a protective layer, the base material layer, the conductive layer and the protective layer are sequentially arranged, the conductive layer is formed by silver paste printed on the surface of the base material layer, and the specific resistance value of the silver paste is smaller than or equal to 1.5 * 10 <-5 > omega.cm; the conductive layer is exposed through a hollow area of the protective layer, a chemical plating immersion gold layer is arranged at the position, corresponding to the hollow area, of the conductive layer, and welding spots of the LED lamp beads are welded to the chemical plating immersion gold layer through solder paste; and a heat dissipation layer formed by heat-conducting ink is arranged on one surface, opposite to the conductive layer, of the base material layer. The heat-conducting ink is printed on the bottom surface of the base material layer of the lamp strip, so that the heat dissipation performance of the lamp strip is improved, the problem of high-current heating of the silver paste printed circuit board is solved, and the silver paste printed circuit board is applied to the side light-emitting LED lamp strip. And the resistance of the conductive layer is not higher than 1.5 * 10 <-5 > omega.cm, so that the conductivity of the conductive layer is improved, and the problem of high-current heating of the silver paste printed circuit board can be solved.

Description

Technical Field

[0001] This application relates to the fields of lighting and backlight modules, and mainly relates to flexible LED strip lights. Background Art

[0002] A utility model patent with the application number "202320328879.7" discloses a flexible LED strip light. The conductive layer of this strip light is made of silver paste. A resistor is connected in series on each LED lamp bead. If the resistance values of the resistors are different, it will cause the current passing through each LED lamp to be inconsistent, resulting in inconsistent luminous brightness of each LED lamp on the strip light. The LED lamp beads generate heat during operation, especially the side-emitting LED lamp beads, which may generate more heat due to their structural characteristics. At the same time, when the silver paste printed circuit board passes a large current, the heat generation situation is serious, which extremely affects the service life of the LED lamp beads. Utility Model Content

[0003] The technical problem to be solved by this application is: to provide an LED strip light with excellent heat dissipation performance.

[0004] To solve the above technical problem, the technical solution adopted by this application is as follows:

[0005] An LED strip light includes LED lamp beads, and a substrate layer, a conductive layer, and a protective layer arranged in sequence. The conductive layer is formed by silver paste printed on the surface of the substrate layer, with a thickness of 5 - 12 μm, and the specific resistance value of the silver paste ≤ 1.5 * 10 -5 Ω·cm; the protective layer has a hollowed-out area that exposes a part of the conductive layer, and an electroless gold plating layer is provided at the position of the conductive layer corresponding to the hollowed-out area, and the thickness of the electroless gold plating layer is 0.03 - 0.19 μm; the solder joints of the LED lamp beads are welded to the electroless gold plating layer through solder paste; a heat dissipation layer formed by heat-conducting ink is provided on one side of the substrate layer relative to the conductive layer, and / or a heat dissipation layer formed by heat-conducting ink is provided on one side of the protective layer relative to the conductive layer.

[0006] Preferably, the conductive layer includes two conductive wires respectively connected to the positive and negative poles of the power supply. The LED lamp beads are arranged between the two conductive wires. The two conductive wires are provided with S-shaped connecting wires corresponding to each LED lamp bead, and the S-shaped connecting wires are designed with different lengths and widths according to the current requirements of the lamp.

[0007] Preferably, the thickness of the heat dissipation layer is 4 - 15 um.

[0008] The bottom heat dissipation of the conductive layer is achieved by printing heat-conducting ink on the bottom surface of the base material layer, which improves the heat dissipation performance of the LED strip, solves the problem of large-current heating of the silver paste printed circuit board, and enables the silver paste printed circuit board to be applied in the side-emitting LED strip. The specific resistance of the conductive layer formed by the silver paste is only 1.5*10 -5 Ω·cm, which improves the conductivity of the conductive layer and can also reduce the problem of large-current heating of the silver paste printed circuit board. The heat-dissipating ink is printed on the protective layer to achieve the upper-layer heat dissipation of the conductive layer. Both heat dissipation methods can significantly improve the heat dissipation performance of the LED strip.

[0009] The specific resistance of the electroless nickel-gold plating layer is lower than that of the silver paste, which is more conducive to the heat dissipation of the LED strip. The electroless nickel-gold plating layer on the silver paste solves the problem that the solder paste does not combine with the silver paste. The solder paste can stably combine with the electroless nickel-gold plating layer, so that the SMT soldering process can also be used on the silver wire, and the problem of quickly, accurately and firmly attaching the lamp beads on the silver wire is solved.

[0010] Preferably, an alloy layer formed by copper alloy paste is provided at the position corresponding to the hollowed-out area of the conductive layer. A nickel deposition layer is provided on one side of the alloy layer relative to the conductive layer, and the electroless nickel-gold plating layer is provided on the nickel deposition layer.

[0011] Preferably, the protective layer is composed of a thin film and an epoxy thermosetting adhesive layer. The thickness of the thin film of the protective layer is 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm. The thickness of the epoxy thermosetting adhesive layer is 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm.

[0012] Preferably, a back glue layer with a thickness of 50-100μm is provided on one side of the protective layer relative to the conductive layer. During use, the back glue layer is attached to the lamp strip carrier. Through holes are provided in the back glue layer corresponding to the LED lamp beads, and the LED lamp beads are located in the through holes, so that it can be ensured that the lamp beads do not contact the lamp fixture carrier and the light emitted by the lamp beads does not leak out.

[0013] In summary, the LED strip of the present application eliminates the external current-limiting resistor, reduces the use of electronic components, saves materials, and also improves the yield. Without using the external resistor, the yield risk caused by the inconsistent resistance values of the external resistors is eliminated. The application of the heat-conducting ink and the electroless nickel-gold plating layer improves the heat dissipation performance and the firmness performance of the lamp beads of the LED strip, enabling the silver paste conduction method to be applied in the side-emitting LED strip. Description of the Drawings

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments.

[0015] Figure 1It is a plan view of the LED light strip in Embodiment 1;

[0016] Figure 2 It is a sectional structure diagram of the light strip installation area in Embodiment 1;

[0017] Figure 3 It is a sectional structure diagram of the light strip installation area in Embodiment 2;

[0018] Figure 4 It is a sectional structure diagram of the light strip installation area in Embodiment 3. Specific embodiments

[0019] In order to make the technical problems, technical solutions and beneficial effects solved by the present utility model clearer, the present utility model will be further described in detail below in conjunction with embodiments.

[0020] Embodiment 1

[0021] Figure 1 and 2 The LED light strip shown in and includes LED lamp beads 10, and a base material layer 20, a conductive layer 30 and a protective layer 40 arranged in sequence. The LED light strip has a lamp bead installation area A and a gold finger B. The conductive layer includes two conductive wires 31 respectively connecting the positive and negative poles of the power supply. The conductive wires extend from the gold finger to the installation area. The LED lamp beads 10 are arrayed between the two conductive wires. The conductive wires are connected to the LED lamp beads through S-shaped connecting wires 32. The protective layer 40 is provided with a hollowed-out area that exposes part of the conductive layer corresponding to the LED lamp beads and the connecting wires. The conductive layer is provided with an electroless nickel immersion gold layer 50 corresponding to the hollowed-out area. The solder joints of the LED lamp beads are welded to the electroless nickel immersion gold layer through solder paste, and the solder paste forms a welding layer 60. A back glue layer 70 with a thickness of 40-100 μm is provided on one side of the protective layer relative to the conductive layer. During use, the back glue layer is attached to the lamp fixture carrier. The back glue layer is provided with through holes 71 corresponding to the LED lamp beads. The topmost end of the LED lamp beads is located in the through holes, so that the lamp beads can be ensured not to contact the lamp fixture carrier.

[0022] The silver paste is coated on the surface of the base material layer through a screen printing process. The formed conductive layer 30 has a thickness of 5-12 μm, preferably 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm. The silver paste adopts a silver paste formula with low resistance, and the specific resistance value of the silver paste ≤ 1.5*10 -5 Ω·cm. In this embodiment, the conductive layer is two silver paste lines, which is suitable for a circuit board with sufficient space. However, sometimes the circuit board is restricted by insufficient mechanical space, and the conductive layer needs to use a jumper process. The jumper process is a common process in the circuit board, so it will not be fully described here. This embodiment is also suitable for the conductive layer of the jumper process.

[0023] The resistance values of the conductive lines formed by screen printing and the connections between the conductive regions are consistent. The LED lamp beads do not require an additional series external current-limiting resistor, reducing the use of electronic components, simplifying the manufacturing process, saving materials, and eliminating the yield risk caused by inconsistent resistance values of external resistors. The specific resistance of the conductive layer is not higher than 1.5*10 -5 Ω·cm, with good electrical conductivity, and it can also solve the problem of large current heating of the silver paste printed circuit board. A chemical plating immersion gold layer (not shown in the figure) is provided on the surface of the silver paste layer, and the protective layer covers the chemical plating immersion gold layer. The thickness of the chemical plating immersion gold layer is 0.03μm - 0.19μm, and the resistance value of the chemical plating immersion gold layer is lower, further solving the problem of large current heating of the silver paste printed circuit board.

[0024] The substrate layer 10 is made of polyimide material and has basically no deformation in a temperature environment within 300°C and can withstand the welding temperature of the LED lamp beads. The substrate layer can also be made of thin film materials such as PET.

[0025] On one side of the substrate layer relative to the conductive layer, a heat dissipation layer 80 formed by heat conductive ink is provided, which can improve the heat dissipation performance of the light strip, solve the problem of large current heating of the silver paste printed circuit board, and the silver paste printed circuit board can be applied in the side-emitting LED light strip. A varnish protective layer is provided at the bottom of the heat dissipation layer to protect the heat dissipation layer from being damaged (not shown in the figure).

[0026] Preferably, the protective layer 40 is composed of a thin film sheet and an epoxy thermosetting adhesive layer, and the thickness of the protective layer is 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm. The thickness of the epoxy thermosetting adhesive layer is 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm. In a possible implementation manner, an insulating layer with a thickness of 8 - 20μm (not shown in the figure) is provided between the conductive layer and the thin film protective sheet to add an additional layer of protection to the conductive layer.

[0027] As Figure 1 shown, the gold finger belongs to a long and narrow structure and is relatively easy to deform relative to the lamp body. In this embodiment, a reinforcing layer corresponding to the gold finger is provided at the bottom of the substrate layer (not shown in the figure) to increase the strength of the gold finger.

[0028] Embodiment Two

[0029] The difference between this embodiment and Embodiment One is:

[0030] Referring to the appendix Figure 3 , an alloy layer 90 formed by printing copper alloy paste is provided at the hollow area of the conductive layer corresponding to the protective layer. A nickel plating layer 100 is provided on one side of the alloy layer relative to the conductive layer, and the chemical plating immersion gold layer 50 is provided on the nickel plating layer 100.

[0031] Embodiment III

[0032] The difference between this embodiment and Embodiment II is that:

[0033] Refer to the appendix Figure 4 , a heat dissipation layer formed by heat-conducting ink is arranged on the side of the protective layer opposite to the conductive layer. The heat dissipation performance of the light strip can also be improved by adopting the heat dissipation method of the upper layer of the conductive layer in this embodiment.

[0034] Embodiment IV

[0035] The difference between this embodiment and Embodiment III is that:

[0036] Heat dissipation layers formed by graphite are arranged on both the substrate layer and the protective layer, and the heat dissipation performance of the light strip is better than that of Embodiment I, Embodiment II, and Embodiment III.

[0037] Various modifications to these embodiments will be obvious to those of ordinary skill in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. An LED light strip, comprising LED lamp beads, and a substrate layer, a conductive layer and a protective layer arranged in sequence, characterized in that: The conductive layer is formed by silver paste printed on the surface of the substrate layer, with a thickness of 5-12 μm, and the specific resistance value of the silver paste is ≤1.5*10 -5 Ω·cm; the protective layer has a hollow area so that the conductive layer is partially exposed, and the conductive layer is provided with a chemical plating gold layer corresponding to the hollow area, and the thickness of the chemical plating gold layer is 0.03-0.19μm; the solder joints of the LED lamp beads are soldered to the chemical plating gold layer through solder paste; the substrate layer is provided with a heat dissipation layer formed by thermal conductive ink on one side relative to the conductive layer, and / or the protective layer is provided with a heat dissipation layer formed by thermal conductive ink on one side relative to the conductive layer.

2. The LED light strip according to claim 1, characterized in that: The thickness of the heat dissipation layer is 4-15um.

3. The LED light strip according to claim 1, characterized in that: An alloy layer formed by printing copper alloy paste is provided at the hollow area corresponding to the conductive layer, a nickel-plated layer is provided on one side of the alloy layer opposite to the conductive layer, and the chemically plated gold-plated layer is provided on the nickel-plated layer.

4. The LED light strip according to claim 1, characterized in that: The protective layer is composed of a film sheet and epoxy thermosetting adhesive, the thickness of the protective layer is 20-100 μm, and the thickness of the epoxy thermosetting adhesive is 10-50 μm.

5. The LED light strip according to claim 4, characterized in that: An insulating layer is provided between the conductive layer and the thin film sheet; the thickness of the insulating layer is 8-20 μm.

6. The LED light strip according to claim 1, characterized in that: A back glue layer is provided on one side of the protective layer opposite to the conductive layer; the thickness of the back glue layer is 50-100 μm.

7. The LED light strip according to claim 6, characterized in that: The adhesive layer is provided with through holes at locations corresponding to the LED lamp beads, and the LED lamp beads are located in the through holes.

8. The LED light strip according to claim 1, characterized in that: The conductive layer includes two conductive wires respectively connected to the positive and negative poles of the power supply, the LED lamp beads are arrayed between the two conductive wires, and the two conductive wires are provided with an S-shaped connecting wire corresponding to each LED lamp bead.

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