Anisotropic conductive adhesive, display panel and electronic equipment

Abstract

The utility model provides an anisotropic conductive adhesive, a display panel and electronic equipment. The anisotropic conductive adhesive comprises an adhesive body, a plurality of conductive particles and a plurality of plastic spacer particles, the plurality of conductive particles and the plurality of plastic spacer particles are arranged in the adhesive body, and the plastic spacer particles are arranged among the plurality of conductive particles. The conductive particle comprises a plastic ball and a nickel layer covering the plastic ball, the nickel layer is formed by nickel powder, and the outer surface, away from the plastic ball, of the nickel layer is provided with a plurality of spikes formed by the nickel powder. The conductive particles are separated by adopting the plastic spacer particles, so that the phenomenon of short circuit caused by aggregation of a plurality of conductive particles in the anisotropic conductive adhesive can be reduced, and the reliability of the anisotropic conductive adhesive is improved. The plastic spacer particles and the conductive particles composed of the nickel layers and the plastic balls are applied to the anisotropic conductive adhesive at the same time, and the conductive particles and the insulating particles / insulating layers of the anisotropic conductive adhesive in the related technology can be replaced.

Description

Technical Field

[0001] The present application belongs to the technical field of anisotropic conductive adhesives, and specifically relates to anisotropic conductive adhesives, display panels and electronic devices. Background Art

[0002] Anisotropic Conductive Film (ACF) is a transparent polymer connection material that has three properties: bonding, conductivity, and insulation. Its notable feature is that it conducts in the vertical direction and insulates in the horizontal direction. ACF is mainly composed of conductive particles and colloids. However, since nickel in the conductive particles has strong magnetism, it is easy to aggregate, and the conductive particles are easily squeezed together under pressure, causing a short circuit. Utility Model Content

[0003] In view of this, the first aspect of the present application provides an anisotropic conductive adhesive, which includes a colloid, a plurality of conductive particles, and a plurality of plastic spacer particles. The plurality of conductive particles and the plurality of plastic spacer particles are both disposed in the colloid, and the plastic spacer particles are disposed between the plurality of conductive particles.

[0004] The anisotropic conductive adhesive provided in the first aspect of the present application separates the nickel in multiple conductive particles by using plastic spacer particles as spacer balls between conductive particles. Since the plastic spacer particles are insulating, the nickel in the conductive particles can be prevented from agglomerating with each other, separating multiple conductive particles, and conducting laterally, causing a short circuit.

[0005] In addition, since the plastic spacer particles have a relatively high hardness, the plastic spacer particles can also reduce the probability of the conductive particles being crushed, thereby preventing the conductive particles from being crushed and having a smaller contact area, which results in poor conductivity.

[0006] Therefore, the present application uses plastic spacer particles to separate the conductive particles, thereby reducing the phenomenon of agglomeration and short circuit of multiple conductive particles in the anisotropic conductive adhesive, thereby improving the reliability of the anisotropic conductive adhesive.

[0007] Wherein, the plastic spacer particles are silicon dioxide and resin particles.

[0008] Wherein, the plastic spacer particles are pure resin particles.

[0009] Wherein, the particle size d1 of the plastic spacer particles satisfies: 1 μm≤d1≤10 μm.

[0010] The conductive particles include a plastic ball and a nickel layer covering the plastic ball. The nickel layer is formed by nickel powder, and the outer surface of the nickel layer away from the plastic ball has a plurality of spikes formed by the nickel powder.

[0011] Wherein, two adjacent spikes are connected; and / or, there is a gap between two adjacent spikes.

[0012] Wherein, the nickel powder satisfies at least one of the following conditions:

[0013] The particle size d2 of the nickel powder satisfies: 1 μm≤d2≤10 μm;

[0014] The density ρ of the nickel powder satisfies: 0.5 g / cm 3 ≤ρ≤2.3g / cm 3 .

[0015] A second aspect of the present application provides a display panel, which includes the anisotropic conductive adhesive provided in the first aspect of the present application.

[0016] The display panel provided in the second aspect of the present application adopts the anisotropic conductive adhesive provided in the first aspect of the present application and uses plastic spacer particles to separate conductive particles, thereby reducing the phenomenon of multiple conductive particles in the anisotropic conductive adhesive agglomerating and short-circuiting, thereby improving the reliability of the anisotropic conductive adhesive.

[0017] The display panel includes a first substrate and a second substrate which are arranged opposite to each other, and the anisotropic conductive adhesive is arranged between the first substrate and the second substrate and is used to electrically connect the electrodes of the first substrate and the electrodes of the second substrate.

[0018] A third aspect of the present application provides an electronic device, which includes a housing and a display panel as provided in the second aspect of the present application, wherein the display panel is mounted on the housing.

[0019] The electronic device provided in the third aspect of the present application adopts the display panel provided in the second aspect of the present application. The anisotropic conductive adhesive in the display panel uses plastic spacer particles to separate the conductive particles, which can reduce the phenomenon of multiple conductive particles in the anisotropic conductive adhesive agglomerating and short-circuiting, thereby improving the reliability of the anisotropic conductive adhesive. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the implementation modes of the present application, the drawings required for use in the implementation modes of the present application will be described below.

[0021] Figure 1 A schematic diagram of the structure of anisotropic conductive adhesive provided in one embodiment of the present application.

[0022] Figure 2 A three-dimensional structural diagram of plastic spacer particles provided in one embodiment of the present application.

[0023] Figure 3 for Figure 2 A partial enlarged view of .

[0024] Figure 4 A schematic diagram of the structure of conductive particles provided in one embodiment of the present application.

[0025] Figure 5 A three-dimensional structural diagram of conductive particles provided in one embodiment of the present application.

[0026] Figure 6 A schematic diagram of the structure of a display panel provided in one embodiment of the present application.

[0027] Explanation of reference numerals: anisotropic conductive adhesive-1, colloid-11, conductive particles-12, plastic balls-121, nickel layer-122, plastic spacer particles-13, display panel-2, first substrate-21, second substrate-22. DETAILED DESCRIPTION

[0028] The following are preferred implementations of the present application. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application, and these improvements and modifications are also considered to be within the scope of protection of the present application.

[0029] Unless otherwise specified or there is a contradiction, the terms and phrases used in this application have the following meanings:

[0030] In this application, "first", "second", etc. are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0031] In this application, "one or several" refers to any one, any two or more of the listed items. Among them, "several" refers to any two or more of the listed items.

[0032] In the present application, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0033] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be connected, detachably connected, or integrated. It can be mechanically connected or electrically connected. It can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0034] In the related technology, the procurement cost of anisotropic conductive adhesive is relatively high. Among them, the process of conductive particles in anisotropic conductive adhesive is complicated. Conductive particles are mainly metal powders and metals coated on the surface of polymer plastic balls. Common metal powders are nickel (NI), gold (AU), gold plated on nickel, etc. Conductive particles need to be evenly electroplated with nickel and gold layers on resin balls, which is difficult to develop. ACF manufacturers usually need to purchase conductive particles from outside.

[0035] Since nickel in the conductive particles has strong magnetism, it is easy to aggregate, and the conductive particles are easily squeezed together under pressure, causing a short circuit. In addition, the conductive particles only have a metal layer on the surface, and the resin inside is not conductive. After the conductive particles are crushed, the contact area becomes smaller, resulting in poor conductivity.

[0036] Please refer to Figure 1-Figure 3 , Figure 1 A schematic diagram of the structure of anisotropic conductive adhesive provided in one embodiment of the present application. Figure 2 A three-dimensional structural diagram of plastic spacer particles provided in one embodiment of the present application. Figure 3 for Figure 2 A partial enlarged view of .

[0037] This embodiment provides an anisotropic conductive adhesive 1, which includes a colloid 11, a plurality of conductive particles 12, and a plurality of plastic spacer particles 13. The plurality of conductive particles 12 and the plurality of plastic spacer particles 13 are both disposed in the colloid 11, and the plastic spacer particles 13 are disposed between the plurality of conductive particles 12.

[0038] The anisotropic conductive adhesive 1 provided in this embodiment includes a colloid 11, which is used to carry conductive particles 12 and plastic spacer particles 13. Optionally, the colloid 11 is an adhesive resin. The colloid 11 can be bonded to other structural parts. For example, the colloid 11 is bonded to the first substrate 21 and the second substrate 22 of the display panel 2.

[0039] The anisotropic conductive adhesive 1 provided in this embodiment further includes a plurality of conductive particles 12 for conducting electricity. For example, the anisotropic conductive adhesive 1 is disposed between the first substrate 21 and the second substrate 22 of the display panel 2, and the conductive particles 12 are disposed between the electrodes of the first substrate 21 and the electrodes of the second substrate 22, and the conductive particles 12 are used to realize electrical connection between the electrodes of the first substrate 21 and the electrodes of the second substrate 22.

[0040] The anisotropic conductive adhesive 1 provided in this embodiment further includes a plurality of plastic spacer particles 13, which are used to act as a spacer and are disposed between the plurality of conductive particles 12. The plastic spacer particles 13 have insulating properties. For example, one plastic spacer particle 13 is located between two conductive particles 12. For another example, a plurality of plastic spacer particles 13 are located between two conductive particles 12. For another example, one plastic spacer particle 13 is located between three conductive particles 12.

[0041] Optionally, the plastic spacer particles 13 are polymer plastic particles. The polymer plastic particles can be used to precisely control the thickness of the liquid crystal panel glass box and support the upper and lower substrates. The polymer plastic particles are now used in the ACF anisotropic conductive adhesive 1 as plastic spacer beads to separate the conductive particles 12.

[0042] In this embodiment, the plastic spacer particles 13 are used as spacer balls between the conductive particles 12 to separate the nickel in the plurality of conductive particles 12. Since the plastic spacer particles 13 are insulating, the nickel in the conductive particles 12 can be prevented from agglomerating with each other, separating the plurality of conductive particles 12 and conducting horizontally, thus causing a short circuit.

[0043] In addition, since the plastic spacer particles 13 have a relatively high hardness, the plastic spacer particles 13 can also reduce the probability of the conductive particles 12 being crushed, thereby preventing the conductive particles 12 from being crushed and having a smaller contact area, thereby preventing the conductivity from being deteriorated.

[0044] Therefore, in this embodiment, the conductive particles 12 are separated by plastic spacer particles 13 , which can reduce the phenomenon of agglomeration and short circuit of a plurality of conductive particles 12 in the anisotropic conductive adhesive 1 , thereby improving the reliability of the anisotropic conductive adhesive 1 .

[0045] In one embodiment, the plastic spacer particles 13 are silicon dioxide and resin particles.

[0046] When the plastic spacer particles 13 are silicon dioxide and resin particles, the plastic spacer particles 13 are made of silicon dioxide, and the plastic spacer particles 13 have high hardness, high modulus, high toughness and high heat resistance. For example, silicon dioxide can be added to epoxy resin to enhance the toughness of the epoxy resin material, greatly improve its mechanical properties, thereby increasing the service life of the epoxy resin material, and SiO2 has good strength, stable chemical properties, and good heat resistance, thereby further improving the mechanical properties, heat resistance, cold resistance, insulation, vibration resistance and chemical resistance of the plastic spacer particles 13.

[0047] Optionally, the plastic spacer particles 13 are silicon dioxide and epoxy resin particles. Optionally, in one embodiment, the coefficient of variation CV1 of the plastic spacer particles 13 satisfies: CV<1.5%. Further optionally, the coefficient of variation CV1 of the plastic spacer particles 13 can be 0.2%, or 0.4%, or 0.6%, or 0.8%, or 1%, or 1.2%, or 1.4%, etc.

[0048] Among them, the particle size of the plastic spacer particles 13 can be customized, ranging from 1μm-10μm, the particle size is very uniform, and the coefficient of variation CV is less than 1.5%; it has good monodispersity, large specific surface area, no overlap or agglomeration; the product has high purity and no pollution; high mechanical strength, K>4500; it has excellent heat resistance, cold resistance, insulation, vibration resistance and chemical resistance; and excellent mechanical properties.

[0049] In one embodiment, the plastic spacer particles 13 are pure resin particles.

[0050] When the plastic spacer particles 13 are pure resin particles, the plastic spacer particles 13 are made of pure resin, and the resin often has high molecular weight, high strength, high heat resistance, corrosion resistance, wear resistance, heat insulation, sound insulation, flame retardancy, etc. For example, the resin has excellent corrosion resistance and is not corroded by chemical substances. The resin has good insulation properties and can be used to make insulating materials and electrical components. The strength of the resin is higher than that of steel, so it can be used to make high-strength structural materials. The resin has a lower specific gravity and weight, and is easy to process and carry. The resin can be manufactured into various shapes and sizes and is suitable for a variety of applications. Pure resin particles are insulating and can prevent the nickel powder of the conductive particles 12 from aggregating with each other, conducting laterally, and causing a short circuit. Among them, the particle size of the plastic spacer particles 13 can be customized, ranging from 1μm-10μm, with uniform particle size and elasticity.

[0051] In one embodiment, the particle size d1 of the plastic spacer particles 13 satisfies: 1 μm ≤ d1 ≤ 10 μm. Optionally, the particle size d1 of the plastic spacer particles 13 may be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, etc.

[0052] Please refer to Figure 1-Figure 5 , Figure 4 It is a schematic diagram of the structure of the conductive particles 12 provided in one embodiment of the present application. Figure 5 The three-dimensional structure diagram of the conductive particle 12 provided in one embodiment of the present application. In one embodiment, the conductive particle 12 includes a plastic ball 121 and a nickel layer 122 covering the plastic ball 121, the nickel layer 122 is formed of nickel powder, and the outer surface of the nickel layer 122 facing away from the plastic ball 121 has a plurality of spikes formed by the nickel powder.

[0053] The conductive particles 12 provided in this embodiment include plastic balls 121, which are used to play a buffering role to prevent the particles from falling off due to different thermal expansion coefficients at the top and bottom. Optionally, the plastic balls 121 are resin balls.

[0054] The conductive particles 12 provided in this embodiment also include a nickel layer 122 for conducting electricity. The nickel layer 122 covers the surface of the plastic ball 121. The nickel layer 122 is formed by nickel powder, and the outer surface of the nickel layer 122 has a plurality of spikes. Nickel powder is a high-purity nickel powder composed of discrete nickel particles with a spike morphology, which has a high melting point, good conductivity, plasticity, corrosion resistance, and protrusions on the surface of the nickel powder. During pressing, the contact area of ​​the nickel powder can be increased, thereby improving the conductivity of the nickel layer 122.

[0055] In this embodiment, the plastic spacer particles 13 and the conductive particles 12 composed of the nickel layer 122 and the plastic balls 121 are simultaneously applied to the anisotropic conductive adhesive 1, so as to replace the conductive particles and the insulating particles / insulating layer of the anisotropic conductive adhesive in the related art.

[0056] In one embodiment, two adjacent spikes are connected; and / or, there is a gap between two adjacent spikes. For example, one spike is connected to another adjacent spike. For another example, there is a gap between one spike and another adjacent spike. For another example, multiple adjacent spikes are connected.

[0057] Optionally, at least some of the plurality of spikes have different heights, so that some of the spikes form protrusions and some of the spikes form depressions.

[0058] In one embodiment, the nickel powder satisfies at least one of the following conditions: the particle size d2 of the nickel powder satisfies: 1 μm ≤ d2 ≤ 10 μm. And / or the density ρ of the nickel powder satisfies: 0.5 g / cm 3 ≤ρ≤2.3g / cm 3 .

[0059] Optionally, the particle size d2 of the nickel powder can be 1 μm, or 2 μm, or 3 μm, or 4 μm, or 5 μm, or 6 μm, or 7 μm, or 8 μm, or 9 μm, or 10 μm, etc.

[0060] Optionally, the density ρ of the nickel powder can be 0.5 g / cm 3 , or 0.8g / cm 3 , or 1.1 g / cm 3 , or 1.4g / cm 3 , or 1.7g / cm 3 , or 2.0g / cm 3 , or 2.3g / cm 3 wait.

[0061] Optionally, in one embodiment, the coefficient of variation CV2 of the nickel powder satisfies: CV<3.5%. Further optionally, the coefficient of variation C2 of the nickel powder may be 0.5%, or 1%, or 1.5%, or 2%, or 2.5%, or 3%, or 3.3%, etc.

[0062] In this embodiment, the particle size is 1 μm-10 μm and the density is 0.5 g / cm 3 -2.3g / cm 3 Nickel powder has uniform particle size and coefficient of variation CV2 less than 3.5%; good dispersion without overlap or agglomeration; suitable hardness, which makes it have stable conductivity and reliability; low impedance and high stability under high temperature and high humidity. In ACF anisotropic conductive adhesive 1, nickel powder can not only be well dispersed and play a good conductive role during pressure extrusion, but also be resistant to high temperature and corrosion.

[0063] In summary, the structure of the anisotropic conductive adhesive 1 provided in this embodiment uses plastic spacer particles 13 as gap balls to reduce the probability of lateral conduction, so as to prevent the nickel powder of the conductive particles 12 from agglomerating and causing short circuits. In addition, the gold layer of the conductive particles in the related art is replaced with a nickel layer 122 formed by pure nickel powder. The nickel powder can not only be well dispersed and play a good conductive role during pressure extrusion, but also be resistant to high temperature and corrosion.

[0064] The present application also provides a display panel, which includes the anisotropic conductive adhesive provided above in the present application.

[0065] The anisotropic conductive adhesive provided in this embodiment can meet the design trend of miniaturization, thinness and shortness of electronic products, especially in the application of liquid crystal display (LCD) and other types of flat panel display devices. For example, it is used in the electrical connection between the driver chip and the substrate of the display panel. For another example, it is used in other microelectronic packaging.

[0066] In liquid crystal panels, the anisotropic conductive adhesive provided by the present application is mainly used in processes that cannot be soldered with high-temperature lead-tin soldering, such as circuit connections of FPC, Plastic Card and LCD, among which driver IC-related applications are the majority. The anisotropic conductive adhesive provided by the present application can be used in the OLB (Outer Lead Bonding) process of connecting to the LCD during TCP / COF packaging and the ILB (Inner Lead Bonding) process of the driver IC connected to the TCP / COF carrier board, or the process of bonding the driver IC to the glass substrate during COG packaging.

[0067] The display panel provided in this embodiment adopts the anisotropic conductive adhesive provided in the present application and uses plastic spacer particles to separate conductive particles, thereby reducing the phenomenon of multiple conductive particles in the anisotropic conductive adhesive agglomerating and short-circuiting, thereby improving the reliability of the anisotropic conductive adhesive.

[0068] Please refer to Figure 6 , Figure 6 A schematic diagram of the structure of a display panel provided in one embodiment of the present application. In one embodiment, the display panel 2 includes a first substrate 21 and a second substrate 22 arranged opposite to each other, and the anisotropic conductive adhesive 1 is arranged between the first substrate 21 and the second substrate 22 and is used to electrically connect the electrodes of the first substrate 21 and the electrodes of the second substrate 22.

[0069] The display panel 2 provided in this embodiment further includes a first substrate 21 and a second substrate 22, and the anisotropic conductive adhesive 1 is bonded to connect the first substrate 21 and the second substrate 22. The conductive particles 12 of the anisotropic conductive adhesive 1 are located between the electrodes of the first substrate 21 and the electrodes of the second substrate 22 to achieve electrical connection between the electrodes of the first substrate 21 and the electrodes of the second substrate 22.

[0070] The present application also provides an electronic device, which includes a housing and a display panel as provided above in the present application, wherein the display panel is mounted on the housing.

[0071] The electronic device provided in this embodiment adopts the display panel provided in the present application. The anisotropic conductive adhesive in the display panel uses plastic spacer particles to separate the conductive particles, which can reduce the phenomenon of multiple conductive particles in the anisotropic conductive adhesive agglomerating and short-circuiting, thereby improving the reliability of the anisotropic conductive adhesive.

[0072] The above is a detailed introduction to the contents provided in the implementation mode of the present application. This article explains and illustrates the principles and implementation modes of the present application. The above explanation is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation mode and application scope. In summary, the contents of this specification should not be understood as limiting the present application.

Claims

1. An anisotropic conductive adhesive, characterized in that: The anisotropic conductive paste includes a colloid, a plurality of conductive particles, and a plurality of plastic spacer particles. The plurality of conductive particles and the plurality of plastic spacer particles are both arranged in the colloid, and the plastic spacer particles are arranged between the plurality of conductive particles.

2. The anisotropic conductive adhesive according to claim 1, characterized in that: The plastic spacer particles are pure resin particles.

3. The anisotropic conductive adhesive according to claim 2, characterized in that: The particle size d1 of the plastic spacer particles satisfies: 1 μm≤d1≤10 μm.

4. The anisotropic conductive adhesive according to claim 1, characterized in that: The conductive particles include a plastic ball and a nickel layer covering the plastic ball. The nickel layer is formed of nickel powder, and an outer surface of the nickel layer facing away from the plastic ball has a plurality of spikes formed of the nickel powder.

5. The anisotropic conductive adhesive according to claim 4, characterized in that: Two adjacent spikes are connected; and / or, there is a gap between two adjacent spikes.

6. The anisotropic conductive adhesive according to claim 4, characterized in that: The nickel powder satisfies at least one of the following conditions: The particle size d2 of the nickel powder satisfies: 1 μm≤d2≤10 μm; The density ρ of the nickel powder satisfies: 0.5 g / cm 3 ≤ρ≤2.3g / cm 3 .

7. A display panel, characterized in that: The display panel includes the anisotropic conductive adhesive as described in claims 1-6.

8. The display panel according to claim 7, wherein: The display panel includes a first substrate and a second substrate which are arranged opposite to each other. The anisotropic conductive adhesive is arranged between the first substrate and the second substrate and is used to electrically connect electrodes of the first substrate and electrodes of the second substrate.

9. An electronic device, characterized in that: The electronic device comprises a housing and a display panel as described in any one of claims 7 to 8, wherein the display panel is mounted on the housing.

Images