Grounding gasket with excellent electroplating adhesive force for direct electroplating type welding and manufacturing method thereof

Abstract

The invention relates to a direct electroplating type grounding gasket, which can be surface-mounted on circuit boards of various communication devices and electronic devices, realizes reflow soldering, and improves electroplating adhesive force. The direct plating type ground pad for improving plating adhesion according to the present invention comprises: an inner elastic body; a palladium-dispersed silica coating layer formed on the surface of the inner elastomer; the first electroplated layer is formed by taking palladium as a seed crystal; and one or more second electroplated layers formed on the outer side of the first electroplated layer, the palladium-dispersed silica coating layer being formed by dispersing palladium (Pd) in a nanosilica hard coating solution by a sol-gel method, and the present invention is characterized in that: the palladium-dispersed silica coating layer is formed on the outer side of the first electroplated layer; and the welding adhesive force with the electronic circuit board is further improved through the specific concave-convex shape of the lower surface.

Description

TECHNICAL FIELD

[0001] The present invention relates to a soldering ground pad, which is surface-mounted to various electronic circuit boards through a soldering process, and more particularly, to a direct plating type soldering ground pad having excellent plating adhesion.

[0002] Also, the present invention relates to the direct plating type soldering ground pad having excellent plating adhesion, which is manufactured using a sol-gel method. BACKGROUND

[0003] Generally, the surface-mounted ground pad is soldered to an electronic circuit board for electrical conduction.

[0004] To this end, the ground pad needs to satisfy the following conditions: good electrical conductivity, stable performance in a high-temperature reflow apparatus of about 260°C to 290°C, easy soldering, and excellent elasticity and restoring force for maintaining good electrical contact, and needs to be firmly attached to the electronic circuit board.

[0005] In the prior art, a method of manufacturing the surface-mounted electrical contact pad includes plating a solderable metal on a polyimide film having high heat resistance to form a conductive skin, or manufacturing a metal foil and then coating a heat-resistant adhesive to wrap an internal elastomer in a form of the internal elastomer as a high-molecular resin, in order to combine the internal elastomer with the conductive skin. The technology uses a winding method of coating the heat-resistant adhesive on the conductive skin and wrapping the internal elastomer, and thus, has the following disadvantages: the adhesive often leaks at a width direction overlapping portion of the skin, resulting in soldering failure during reflow soldering, and the manufacturing process is complicated, requiring plating of the metal on the polyimide film to form the conductive skin, coating of the adhesive and wrapping of the internal elastomer, etc.

[0006] In still another prior art, a conductive silicone rubber using a mixture of silicone resin and silver powder is used to manufacture the surface-mounted electrical contact pad, and a metal foil is attached to one surface to achieve soldering. The technology has high product cost due to the use of the silver powder, and has a complicated metal foil attachment process and problems in the bonding force of the metal foil.

[0007] In yet another prior art, after alkali degreasing of a high-molecular resin, a surface is treated with a silane-based coupling agent to impart polarity, and then palladium is adsorbed to perform electroless plating, but there is a problem in that it is difficult to secure plating adhesion for a silicone resin or a fluorine resin having low adhesion. SUMMARY

[0008] Technical Problem to be Solved by the Invention

[0009] The present invention relates to a direct plating type soldering ground pad having excellent plating adhesion.

[0010] Still another problem to be solved by the present application is to provide a method of manufacturing the direct plating type soldering ground pad using a sol-gel method and an electroplating method.

[0011] Technical Solution for Solving the Technical Problem

[0012] The inventors of the present application have found, through long-term research, that the adhesion between an internal elastomer and each layer formed thereon can be improved by forming a palladium (Pd)-dispersed silica coating solution using a sol-gel method, coating the same on the surface of the internal elastomer, and then forming an electroplating layer.

[0013] Also, it has been found through research that the soldering adhesion to an electronic circuit board can be further improved by increasing the contact area and the rubber embedding phenomenon, if a specific concavo-convex shape is imparted to the lower surface of the pad soldered to the electronic circuit board.

[0014] More specifically, to solve the problem, the direct plating type soldering ground pad having excellent electroplating adhesion according to the present application includes an internal elastomer having a cushioning property, a palladium-dispersed silica coating layer formed on the upper surface, the lower surface, and at least a portion of the side surface connecting the upper surface and the lower surface of the internal elastomer, an internal electroplating layer formed on the palladium-dispersed silica coating layer, and one or more external electroplating layers formed on the internal electroplating layer.

[0015] The lower surface of the internal elastomer can include a concavo-convex structure.

[0016] The concavo-convex structure can be a chamfered concavo-convex type, a stepped concavo-convex type, or a multiple concavo-convex type.

[0017] The internal elastomer can include a through hole formed in the length direction.

[0018] The internal elastomer can be a sponge-like foam.

[0019] The palladium-dispersed silica coating layer can further include a silane coupling agent.

[0020] The internal electroplating layer or the external electroplating layer can include at least one of copper, gold, silver, iron, nickel, tin, zinc, chromium, aluminum, magnesium, titanium, tungsten, cobalt, lead, and lithium.

[0021] To solve the problem, the direct plating type ground pad for improving plating adhesion according to the present application can include the steps of forming an inner elastic body; preparing a palladium dispersed silica coating solution by performing a sol-gel reaction on a precursor solution including a silica precursor and palladium; coating the palladium dispersed silica coating solution on a surface of the inner elastic body to form a palladium dispersed silica coating layer; forming an inner plating layer on the palladium dispersed silica coating layer using palladium as a seed; and forming one or more outer plating layers on the inner plating layer.

[0022] The present application can further include the step of cutting the inner elastic body on which the palladium dispersed silica coating layer is formed into a predetermined length.

[0023] The palladium dispersed silica coating layer can be pre-cured before the inner plating layer is formed, and fully cured after the inner plating layer is formed.

[0024] Effects of the Invention

[0025] The direct plating type ground pad for improving plating adhesion according to the present application can improve the adhesion of the inner elastic body and the plating layer by dispersing palladium (Pd) in a nano-silica hard coating solution using a sol-gel method, and can further improve the plating adhesion to an electronic circuit board by increasing the contact area and the rubber insertion phenomenon using a specific concave-convex shape on the lower surface of the pad.

[0026] Further, the direct plating type ground pad according to the present application can reduce the manufacturing process and thus reduce the cost due to the simplified structure.

[0027] Further, the direct plating type ground pad according to the present application can form a strong silica coating layer using a silica coating solution manufactured using a sol-gel method even when a non-sticky material such as silicone rubber or fluorine rubber having strong release properties is used as the inner elastic body, and can directly perform plating thereon with high plating adhesion.

[0028] Therefore, even when a non-sticky material having strong release properties is used as the inner elastic body, the structure can be simplified, and the problem can be solved by eliminating the process and the layers that cause the problem from the root, for example, eliminating the plating failure caused by the adhesive leakage, and the like, simplifying the complicated process of attaching the inner elastic body and the conductive outer skin using the adhesive, and reducing the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 FIG. 1 is a cross-sectional view of a direct plating type ground pad for improving plating adhesion according to an embodiment of the present application.

[0030] Figure 2To briefly show a sectional view of a direct plating type ground pad for welding according to another embodiment of the present application, a chamfered concavo-convex structure is formed on a lower surface of the ground pad.

[0031] Figure 3 To briefly show a sectional view of a direct plating type ground pad for welding according to another embodiment of the present application, a chamfered concavo-convex structure is formed on a lower surface of the ground pad.

[0032] Figure 4 To briefly show a sectional view of a direct plating type ground pad for welding according to another embodiment of the present application, a chamfered concavo-convex structure is formed on a lower surface of the ground pad.

[0033] Figure 5 To briefly show a sectional view of a direct plating type ground pad for welding according to another embodiment of the present application, a chamfered concavo-convex structure is formed on a lower surface of the ground pad.

[0034] Explanation of Reference Numerals

[0035] 10: Printed Circuit Board (PCB)

[0036] 20: Solder

[0037] 110: Inner Elastomer

[0038] 115: Additive Material

[0039] 117: Through Hole

[0040] 120: Palladium Dispersed Silica Coating

[0041] 130: Plating Layer

[0042] 210, 310, 410: Concavo-Convex Structure DETAILED DESCRIPTION

[0043] The advantages, features and methods of carrying out the present application will be apparent from the embodiments, with reference to the accompanying drawings, as well as the following detailed description. However, the present application is not limited to the embodiments disclosed below, but can be implemented in various different embodiments, and the embodiments are provided only to completely disclose the present application and to enable a person of ordinary skill in the art to which the present application pertains to fully understand the scope of the present application, which is defined only by the scope of the claims.

[0044] Hereinafter, a direct plating type ground pad for welding having excellent plating adhesion and a method of manufacturing the same according to a preferred embodiment of the present application will be described in detail with reference to the accompanying drawings.

[0045] Figure 1 To briefly show a sectional view of a direct plating type ground pad for welding according to another embodiment of the present application, a chamfered concavo-convex structure is formed on a lower surface of the ground pad.

[0046] Referring toFigure 1 The direct plating type ground pad 100 for welding includes an inner elastic body 110, a palladium dispersed silica coating 120, and a plating layer 130.

[0047] The inner elastic body 110 uses a material and / or structure having a cushioning property.

[0048] The inner elastic body 110 can be a sponge-like foam. Also, the inner elastic body can be a material including one or more of silicone rubber, fluorine rubber, synthetic rubber, and thermoplastic elastomer.

[0049] If necessary, the inner elastic body 110 can include an additive material 115. The additive material 115 can be a flame retardant material, a heat resistance reinforcing material, etc.

[0050] Also, the inner elastic body 110 can be formed as a sponge-like foam by another method of achieving a proper cushioning property. In this case, the foam can include open-cell foam and closed-cell foam, but in order to reduce high-temperature thermal expansion during reflow, open-cell foam is preferred.

[0051] The inner elastic body 110 can include one or more rubbers or resins selected from silicone rubber, fluorine rubber, synthetic rubber, and thermoplastic elastomer.

[0052] For example, in the case where the inner elastic body 110 is not silicone rubber, fluorine rubber, or synthetic rubber having a basic heat resistance, but is a thermoplastic polymer material having insufficient heat resistance, in order to improve the heat resistance, a heat resistance reinforcing material can be added to the inner elastic body 110. For example, in the case of double extrusion, a rigid segment can be added to the polymer resin of the outer portion requiring plating, and simple blending or dynamic cross-linking can be performed to improve the heat resistance.

[0053] For example, when the internal elastomer 110 is a thermoplastic elastomer, two different components are required in the molecule, a flexible segment for maintaining rubber-like elasticity, which can use butadiene rubber (BR), isoprene rubber (IR), butyl rubber (IIR), ethylene-propylene rubber (EPDM), and polyether, and a rigid segment for preventing plastic deformation, which can add polypropylene, polystyrene, nylon, styrene-acrylonitrile, and polyethylene, and the addition amount is preferably 40% to 70%. In this case, when dynamically crosslinking, the crosslinking agent can be selected from one of a phenol resin system, a bismaleimide system, a zinc oxide system, and a halogenated melamine system, and in order to improve heat resistance and high-temperature mixing stability, a phenol-based or amine-based heat-resistant antioxidant, a stabilizer, and a plasticizer can be added, and the heat resistance can be improved to 200°C or more.

[0054] As still another example, in order to improve the flame retardancy of the internal elastomer 110, a non-halogen flame retardant material can be added to the internal elastomer 110.

[0055] Figure 1 The shape of the internal elastomer 110 is shown as a square cross section as a base type, but is not limited thereto, and can be a polygonal shape such as a triangle or a circular shape, a semicircular shape, or the like. Also, the internal elastomer 110 can be a tubular or sheet structure. A lower protrusion 116 can be formed at the lower portion of the internal elastomer 110.

[0056] The palladium-dispersed silica coating 120 can be formed on at least one of the upper surface, the lower surface, and the side surface connecting the upper surface and the lower surface of the internal elastomer 110. For example, the palladium-dispersed silica coating 120 can be formed on the front surface of the internal elastomer 110.

[0057] As still another example, the palladium-dispersed silica coating 120 can be formed only on the upper surface, the lower surface, the front surface, and the back surface of the internal elastomer 110. In this case, the left and right side surfaces of the internal elastomer 110 can be in an exposed state.

[0058] The palladium-dispersed silica coating is a coating mainly including silica (SiO2) particles (for example, mainly including nano-silica particles), and palladium particles are dispersed between the silica particles. With respect to the silica particles, excellent adhesion between the internal elastomer (for example, a high-molecular resin) and the silica coating can be achieved. Furthermore, the adhesion between the silica particles and the electroplated metal is also good. On the other hand, the palladium particles dispersed between the silica particles act as seeds for the internal electroplated layer. Ultimately, the palladium-dispersed silica coating applied to the present application not only enables electrolysis-free electroplating, but also contributes to improving the electroplated adhesion of the electroplated layer 130 to the substrate, that is, the electroplated adhesion to the internal elastomer 110.

[0059] The palladium-dispersed silica coating 120 can further include a silane coupling agent.

[0060] The plating layer 130 includes an inner plating layer and one or more outer plating layers. The inner plating layer can be formed by an electroless plating method using the palladium of the palladium-dispersed silica coating as a seed. The outer plating layer is formed on the inner plating layer in one or more layers to compensate for the thin plating thickness of the inner plating layer formed by the electroless plating method. The outer plating layer can be formed by an electrolytic plating method.

[0061] Preferably, the plating layer 130 has an electrical conductivity of 0.1 Ω or less. If the electrical conductivity exceeds 0.1 Ω, the electrical connection can be degraded, which can result in poor efficiency.

[0062] The inner plating layer or the outer plating layer constituting the plating layer 130 can include at least one of copper, gold, silver, iron, nickel, tin, zinc, chromium, aluminum, magnesium, titanium, tungsten, cobalt, lead, and lithium. The inner plating layer and the outer plating layer can be of the same material or of different materials.

[0063] A rust-preventing treatment layer (not shown) can be formed on the surface of the outer plating layer to prevent discoloration and corrosion.

[0064] Figures 2 to 4 Other embodiments of the direct plating type ground pad for soldering according to the present application are shown, in which a concavo-convex structure is formed on the lower surface of the ground pad. For example, the concavo-convex structure can be a chamfered concavo-convex type, a stepped concavo-convex type, or a multiple concavo-convex type.

[0065] Specifically, in the direct plating type ground pad for soldering 200 of the embodiment, a chamfered concavo-convex structure is formed on the lower surface of the ground pad. Referring to FIG. 2, the lower surface of the inner elastic body 210 is chamfered on both sides of the lower surface. Figure 2 The chamfered concavo-convex structure of the direct plating type ground pad for soldering 200 of the embodiment is formed on the lower surface of the inner elastic body 210. Referring to FIG. 2, the lower surface of the inner elastic body 210 is chamfered on both sides of the lower surface. Figure 2 The chamfered concavo-convex structure of the direct plating type ground pad for soldering 200 of the embodiment is formed on the lower surface of the inner elastic body 210. Referring to FIG. 2, the lower surface of the inner elastic body 210 is chamfered on both sides of the lower surface. Figure 1 Compared to the structure shown in FIG. 1, the chamfered concavo-convex structure of the direct plating type ground pad for soldering 200 of the embodiment can ensure a wider solder contact area and can have an effect of embedding the lower portion in the solder 20.

[0066] In the direct plating type ground pad for soldering 300 of the embodiment, a stepped concavo-convex structure is formed on the lower surface of the ground pad. Figure 3 In the direct plating type ground pad for soldering 300 of the embodiment, a stepped concavo-convex structure is formed on the lower surface of the ground pad. Figure 4 In the direct plating type ground pad for soldering 400 of the embodiment, a multiple concavo-convex structure is formed on the lower surface of the ground pad. Also, compared to the structure shown in FIG. 1, the multiple concavo-convex structure of the direct plating type ground pad for soldering 400 of the embodiment can ensure a wider solder contact area and can have an effect of embedding the lower portion in the solder 20. Figure 1 Compared to the structure shown in FIG. 1, the multiple concavo-convex structure of the direct plating type ground pad for soldering 400 of the embodiment can ensure a wider solder contact area and can have an effect of embedding the lower portion in the solder 20. Figure 3 In the direct plating type ground pad for soldering 400 of the embodiment, a multiple concavo-convex structure is formed on the lower surface of the ground pad. Also, compared to the structure shown in FIG. 1, the multiple concavo-convex structure of the direct plating type ground pad for soldering 400 of the embodiment can ensure a wider solder contact area and can have an effect of embedding the lower portion in the solder 20. Figure 4 Compared to the structure shown in FIG. 1, the multiple concavo-convex structure of the direct plating type ground pad for soldering 400 of the embodiment can ensure a wider solder contact area and can have an effect of embedding the lower portion in the solder 20.

[0067] Also, as shown in Figures 2 to 4 the lower uneven structure 210, 310, 410 at the time of welding can further improve the welding adhesion with the electronic circuit board by enlarging the contact area of the ground pad and the embedding phenomenon of the rubber.

[0068] Also, referring to Figures 2 to 4 , the internal elastic body 110 can include a through-hole 117 formed in the length direction. Through the through-hole 117, the ground pad can be given appropriate cushioning and extrusion resilience.

[0069] The through-hole 117 can be formed in a circular, semicircular, square, triangular, or other polygonal cross-section, and can be formed in more than one.

[0070] Figure 5 A manufacturing method of the direct plating type ground pad for welding according to an embodiment of the present application is briefly shown.

[0071] Referring to Figure 5 , the manufacturing method of the direct plating type ground pad for welding includes an internal elastic body forming step (S511), a palladium-dispersed silica coating solution preparation step (S512), a palladium-dispersed silica coating forming step (S520), an internal plating layer forming step (S530), and an external plating layer forming step (S540).

[0072] In the internal elastic body forming step (S511), the internal elastic body is formed in a predetermined shape (for example, a shape including a lower protrusion (116 in Figure 1 or a lower unevenness (310 in Figure 3 , etc.). The internal elastic body can be formed by injection molding, sheet molding, and longitudinal cutting, etc., and is preferably formed by a continuous extrusion process.

[0073] The extrusion process can be a process in which at least one rubber or resin selected from among silicone rubber, fluorine rubber, synthetic rubber, and thermoplastic elastomer is fed into an extruder, and then passes through a die by the pressure of a pressurizing device such as a screw.

[0074] In this case, for example, Figures 2 to 4 the cross-sectional shape of the internal elastic body can be determined by the die. If the internal elastic body formed by the die is silicone rubber, primary vulcanization can be performed for several seconds in a temperature range of 200°C to 500°C. The internal elastic body that has undergone the primary vulcanization can be subjected to secondary vulcanization for 1 to 12 hours at 100°C to 220°C, thereby achieving complete curing.

[0075] On the other hand, before coating the inner elastomer, a process of removing oil, impurities, foreign matter, or modifying the surface of the inner elastomer can be included by washing or degreasing. For example, the washing and / or surface modification process can be performed by one or more of acid washing, plasma, alkaline degreasing, ultraviolet (UV) irradiation treatment.

[0076] The alkaline degreasing can be performed in a degreasing solution such as sodium hydroxide (NaOH), potassium hydroxide (KOH), etc. for about 5 minutes to 15 minutes, and in addition, the washing and surface modification processes according to various resin types known in the art can be performed according to a suitable process.

[0077] In the palladium-dispersed silica coating solution manufacturing step (S512), a process of performing a sol-gel reaction on a precursor solution including a silica precursor and palladium (or a palladium salt) is included, thereby manufacturing a palladium-dispersed silica coating solution.

[0078] For example, the palladium-dispersed silica coating solution can be manufactured by adding distilled water (H2O), nitric acid (HNO3), ethanol, and palladium (or a palladium salt) to a silica precursor such as tetramethoxysilane (TMOS), tetraethyl orthosilicate (TEOS), etc., and performing a sol-gel reaction through hydrolysis and condensation.

[0079] The size of the silica (SiO2) generated through the sol-gel reaction can grow to about 5 nm to 100 nm, and more preferably, to nanoscale nanosilica having a size of about 10 nm to 30 nm.

[0080] Also, the precursor solution can further include a silane coupling agent. The silane coupling agent can be selected from one or more of a vinyl group, an epoxy group, a styryl group, a methacryloxy group, an acryloxy group, an amino group, a ureide group, an isocyanate group, an isocyanurate group, a mercapto group, etc. Preferably, methacryloxypropyl trimethoxysilane (MPTMS), glycidoxypropyl trimethoxysilane (GPTMS), etc. can be selected.

[0081] The silica coating solution without dispersed palladium can include stannous chloride (SnCl2) and a palladium salt dissolved in an alcohol, for example, can include palladium chloride (PdCl2) for the dispersion of palladium. Further, the silica coating solution with dispersed palladium can further include stannous chloride (SnCl2) and palladium chloride (PdCl2) dissolved in an alcohol for the further dispersion of palladium. When palladium chloride (PdCl2) is dispersed in the silica coating solution without palladium, the palladium chloride can be introduced in a weight ratio of about 0.5% to 5% with respect to 100 parts by weight of the silica coating solution. The stannous chloride (SnCl2) and the palladium chloride (PdCl2) dissolved in the alcohol can be a solution of about 5 wt% to 10 wt%. Also, the stannous chloride and the palladium chloride can be introduced in a weight ratio of 3: 1 to 4: 1.

[0082] The alcohol can be selected from ethanol, methanol, butanol, isopropyl alcohol, etc.

[0083] In the preparation of the palladium-dispersed silica coating solution, a stirring step can be included. The stirring can be performed using a magnetic stirrer, an ultrasonic stirrer, etc.

[0084] Also, the palladium-dispersed silica coating solution can be diluted to a solution of about 2 times to 4 times by the alcohol to control the thickness of the palladium-dispersed silica coating.

[0085] Next, in the palladium-dispersed silica coating formation step (S520), the palladium-dispersed silica coating solution is coated on the inner elastomer surface and dried to form a palladium-dispersed silica coating.

[0086] The coating method can be performed by a known method such as brushing, spraying, dipping, etc. The drying can also be performed by a known method such as natural drying, hot air drying, etc.

[0087] After the palladium-dispersed silica coating is formed, the formed coating can be cured. The curing can be performed using a known curing device such as a box furnace, a tunnel furnace, etc.

[0088] The cleaning and / or surface modification process, the coating process, and the pre-curing process can be performed by a continuous process in-line. The continuous process can be performed by a dipping method at a speed of 100 mm / min to 500 mm / min. In this case, if the speed is faster than 500 mm / min, the coating film thickness can be too thick, which can cause a decrease in adhesion and plating quality, and if the speed is slower than 100 mm / min, the coating film thickness can be too thin, which can also cause a decrease in adhesion and plating quality.

[0089] On the other hand, it is preferable that the palladium-dispersed silica coating layer is pre-cured before the inner plating layer formation, and is fully cured after the inner plating layer formation. For example, the palladium-dispersed silica coating layer can be pre-cured at about 60°C to 200°C for about 1 minute to 10 minutes to form a nanosilica coated film, and is fully cured at about 80°C to 250°C for about 10 minutes to 3 hours after the inner plating layer formation step in a state where palladium (Pd) is exposed (before the pores are closed).

[0090] After the palladium-dispersed silica coating layer formation step (S520), a step of cutting the inner elastomer on which the palladium-dispersed silica coating layer is formed to a predetermined length (S527) can be further performed. For example, the inner elastomer is manufactured to be longer than the length of a target product, or is continuously manufactured on-line, and after the palladium-dispersed silica coating layer is formed on the surface thereof, if plating is performed after cutting to the target length in a pre-cured state, the cut surface of the inner elastomer is not plated, and the plating layer can be formed only on the surface of the inner elastomer which is not cut.

[0091] The cutting can be performed by a ring knife, a shearing blade, a Thomson blade, or the like.

[0092] The ground pad of a desired size can be obtained through the cutting step (S527). In particular, both side surfaces of the inner elastomer can be in an exposed state through the cutting step (S527). The cut cross-section portion is not plated, and since it has a shape in which a two-dimensional plating sheet is curled, even if it is repeatedly pressed, the plating layer can not be damaged.

[0093] Next, in the inner plating layer formation step (S530), an inner plating layer is formed on the palladium-dispersed silica coating layer using palladium as a seed. The inner plating layer can be formed by an electroless plating method using the palladium particles of the palladium-dispersed silica coating layer as a seed.

[0094] The plating metal can include one or more of copper, gold, silver, iron, nickel, tin, zinc, chromium, aluminum, magnesium, titanium, tungsten, cobalt, lead, lithium, or the like. For example, a single metal, a combination of two to three metals, or the like can be formed by electroless plating, and preferably, boron-based nickel (Ni-B) or phosphorus-based nickel (Ni-P) can be formed. The boron-based nickel (Ni-B) electroless plating can be performed at a temperature of 45°C to 65°C for 5 minutes to 30 minutes, and can be performed in a barrel.

[0095] Next, in the outer plating layer formation step (S540), one or more outer plating layers are formed on the inner plating layer. The outer plating layer can be formed by an electrolytic plating method. The outer plating layer formation step can be performed in a barrel.

[0096] Preferably, the outer metal layer can be formed of copper to ensure good electrical conductivity, and can be formed in a copper sulfate plating solution at a current density of 0.3 A / dm 2 -1.5 A / dm 2 for about 30 minutes to 90 minutes.

[0097] Preferably, the additional outer metal layer can be formed of tin to achieve good solderability and prevent corrosion of the second metal layer, and can be formed in an organic acid tin plating solution at a current density of 0.1 A / dm 2 -1 A / dm 2 for about 5 minutes to 20 minutes.

[0098] The inner plating layer can be formed to be about 0.2 μm to 2 μm, and the outer plating layer can be formed to be about 2 μm to 10 μm. Also, if necessary, an additional plating layer of about 1 μm to 5 μm can be formed on the outer plating layer.

[0099] Rust-proof treatment can be performed on the outside of the plating layer to prevent discoloration and corrosion.

[0100] As described above, the direct plating type soldering ground pad of the present application can improve the adhesion of the inner elastomer to the plating layer by using the palladium (Pd) dispersed silica coating formed by the nano-silica hard coating solution of the sol-gel method.

[0101] Further, by using a specific concavo-convex shape on the lower surface of the soldered inner elastomer, the soldering adhesion to the electronic circuit board can be further improved by increasing the contact area and the rubber embedding phenomenon.

[0102] The above has been described centering on one embodiment of the present application, but those skilled in the art can make various changes or modifications within the skill level. Such changes and modifications should be considered to belong to the present application as long as they do not depart from the scope of the present application. Therefore, the scope of the claims of the present application should be judged based on the appended claims for protection.

Claims

1. A direct electroplating type ground pad for soldering, characterized by, Comprising: an internal elastomer having cushioning properties; a palladium-dispersed silica coating layer formed on at least one of an upper surface, a lower surface, and a side surface connecting the upper surface and the lower surface of the internal elastomer; an internal plating layer formed on the palladium-dispersed silica coating layer; and one or more external plating layers formed on the internal plating layer, the internal elastomer is made of one or more of silicone rubber, fluororubber, synthetic rubber, and thermoplastic elastomer, in the palladium-dispersed silica coating layer, palladium particles are dispersed between silica particles. The palladium-dispersed silica coating layer is formed by dispersing palladium in a nanosilica hard coating solution prepared using a sol-gel method.

2. The direct electroplating type ground pad for welding according to claim 1, characterized by The lower surface of the internal elastomer includes a concave-convex structure.

3. The direct electroplating type ground pad for welding according to claim 1, characterized by The concave-convex structure is a chamfered concave-convex type, a stepped concave-convex type, or a multiple concave-convex type.

4. The direct electroplating type ground pad for welding according to claim 3, characterized by The internal elastomer includes a through-hole formed in a lengthwise direction.

5. The direct electroplating type ground pad for welding according to claim 1, wherein The internal elastomer is a sponge-like foam.

6. The direct electroplating type ground pad for welding according to claim 1, wherein The palladium-dispersed silica coating layer further includes a silane coupling agent.

7. The direct electroplating type ground pad for welding according to claim 1, wherein The internal plating layer or the external plating layer includes at least one of copper, gold, silver, iron, nickel, tin, zinc, chromium, aluminum, magnesium, titanium, tungsten, cobalt, lead, and lithium.

8. The direct electroplating type ground pad for welding according to claim 1, wherein Comprising the steps of:

9. A method of manufacturing a direct electroplating type ground pad for welding, characterized by, forming an internal elastomer; preparing a palladium-dispersed silica coating solution by subjecting a precursor solution including a silica precursor and palladium to a sol-gel reaction; coating the palladium-dispersed silica coating solution on a surface of the internal elastomer to form a palladium-dispersed silica coating layer; forming an internal plating layer on the palladium-dispersed silica coating layer using palladium as a seed crystal; and forming one or more external plating layers on the internal plating layer, the internal elastomer is made of one or more of silicone rubber, fluororubber, synthetic rubber, and thermoplastic elastomer, in the step of forming the palladium-dispersed silica coating layer, the palladium-dispersed silica coating layer in which palladium particles are dispersed between silica particles is formed. The internal plating layer is formed by an electroless plating method, and the external plating layer is formed by an electrolytic plating method.

10. The method of producing a direct electroplating type ground pad for welding according to claim 9, characterized by, Further comprising the steps of:

11. The direct electroplating type ground pad for welding manufacturing method according to claim 9, characterized by cutting the internal elastomer on which the palladium-dispersed silica coating layer is formed into a predetermined length. pre-curing the palladium-dispersed silica coating layer before forming the internal plating layer, and fully curing the palladium-dispersed silica coating layer after forming the internal plating layer.

12. The direct electroplating type ground pad for welding manufacturing method according to claim 9, characterized by, ​

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