WO2023058797A1 - Conductive carbon-based particles having excellent corrosion resistance - Google Patents

Conductive carbon-based particles having excellent corrosion resistance Download PDF

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WO2023058797A1
WO2023058797A1 PCT/KR2021/013907 KR2021013907W WO2023058797A1 WO 2023058797 A1 WO2023058797 A1 WO 2023058797A1 KR 2021013907 W KR2021013907 W KR 2021013907W WO 2023058797 A1 WO2023058797 A1 WO 2023058797A1
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layer
based particles
silver
carbon
conductive carbon
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PCT/KR2021/013907
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French (fr)
Korean (ko)
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김상호
최성웅
조형근
최윤호
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주식회사 씨앤씨머티리얼즈
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Priority to PCT/KR2021/013907 priority Critical patent/WO2023058797A1/en
Priority to KR1020247010421A priority patent/KR20240051233A/en
Publication of WO2023058797A1 publication Critical patent/WO2023058797A1/en

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/158—Carbon nanotubes
    • C01B32/168—After-treatment
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/182—Graphene
    • C01B32/194—After-treatment
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/20—Graphite
    • C01B32/21—After-treatment
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20—Conductive material dispersed in non-conductive organic material
    • H01B1/24—Conductive material dispersed in non-conductive organic material the conductive material comprising carbon-silicon compounds, carbon or silicon

Definitions

  • the present invention relates to conductive carbon-based particles having a conductive metal coating layer, and in particular, a copper metal layer is formed on the surface without an expensive palladium catalyst layer, and a nickel or silver coating layer is additionally formed to protect the copper metal layer. It relates to excellent conductive carbon-based particles and a manufacturing method thereof.
  • Conductive particles are widely used in electronic materials. Among them, metal particles such as copper or nickel have high conductivity and are highly competitive in price, so they are widely used in films, adhesives, and coating slurries that require electrical conductivity in many electronic parts.
  • metal particles are difficult to produce particles of various sizes in the synthesis process, and it is difficult to maintain particle size uniformity and spherical shape between particles, making it difficult to make a film or adhesive layer of uniform thickness when manufacturing a conductive film or adhesive, It also becomes difficult to keep the contact characteristics uniform.
  • a large volume of metal particles is added to the film or adhesive, and a high volume ratio of the metal particles may cause problems in that the film or adhesive layer becomes heavy and the adhesive strength is weakened.
  • carbon-based particles having a low density, excellent chemical resistance, and conductivity of a certain level or more are also widely used as a conductive material.
  • the carbon-based particles include graphite particles, graphene particles, and CNT particles.
  • the film or adhesive layer made of these carbon-based particles still has a problem in that the conductivity is lower than that of the metal particles.
  • conductive carbon-based particles in which a conductive metal layer such as copper, nickel, silver, or gold is formed on the surface of carbon-based particles such as graphite, graphene, and CNT, which have low density and excellent chemical resistance.
  • the base material carbon-based particles and the metal layer are different materials, it is difficult to maintain bonding strength.
  • a method of forming a metal layer after forming a catalyst layer using palladium is often used, but palladium is too expensive, so the process cost increases.
  • the metal layer coated on the surface of the carbon-based particles may be made of various metals. Copper has excellent conductivity close to silver, but has a problem of being easily oxidized, and nickel has excellent corrosion resistance, so it has advantages in long-term reliability, etc. There is a problem of low electrical conductivity. Another metal, silver (Ag), is excellent in both conductivity and corrosion resistance, but has a problem in that its price is too high.
  • An object of the present invention is to provide conductive carbon-based particles having a metal layer having excellent electrical conductivity and at the same time excellent corrosion resistance and bonding strength with carbon-based particles formed on the surface of the conductive carbon-based particles.
  • Another object of the present invention is to provide a method for manufacturing conductive carbon-based particles capable of forming a metal layer having excellent electrical conductivity and excellent corrosion resistance and bonding strength with carbon-based particles on the surface of the conductive carbon-based particles at low cost.
  • conductive carbon-based particles including a third layer including silver may be provided.
  • the carbon-based particles may be one or more selected from the group consisting of graphite, graphene, and CNT.
  • the first layer further includes metallic silver, and the molar ratio of the silver element in the silver oxide to the silver element in the metallic silver (Ag x + /Ag 0 ( 0 ⁇ x ⁇ 3 )) is in the range of 1 to 20 can
  • the first layer may further include tin.
  • the content of silver included in the first layer may be 10 to 1,000 ppm of the total weight of the conductive carbon-based particles.
  • the third layer may further include phosphorus together with the nickel.
  • the third layer may include 0.1 to 13.0% by weight of phosphorus.
  • the method for manufacturing conductive carbon-based particles according to the present invention includes (a) a hydrophilization step of hydrophilizing the surface of carbon-based particles, (b) forming a first layer of coating silver oxide on carbon-based particles whose surfaces are hydrophilized (c) forming a second layer of electrolessly plating copper on the first layer; and (d) forming a third layer of electroless plating of nickel or silver on the second layer.
  • steps (a) and (b) a step of forming a tin layer may be further included.
  • a post-treatment step of adjusting the amount of silver oxide by stirring the carbon-based particles having the first layer in an aqueous solution having a pH of 8 to 14 and a temperature of 20 to 80 ° C. may further include.
  • the conductive carbon-based particles according to the present invention are inexpensive and have excellent electrical conductivity and corrosion resistance, so that they can be applied to various electronic parts that require electrical conductivity, and the bonding strength of the surface metal layer is excellent, so that the applied parts can be reduced in weight and improved in conductivity and reliability. be able to
  • the method for manufacturing conductive carbon-based particles provided in the present invention enables mass production of conductive carbon-based particles having excellent conductivity and reliability through a low-cost process.
  • Figure 2 shows the analysis results according to the X-ray photoelectron spectroscopy (XPS) for the conductive carbon-based particles in one embodiment according to the present invention.
  • XPS X-ray photoelectron spectroscopy
  • Carbon-based particles have the advantages of excellent chemical resistance and low density, but their use as conductive particles is limited because their electrical conductivity is not high. To overcome this, if a conductive metal layer is formed on the surface, conductivity can be imparted to carbon-based particles of various shapes and sizes.
  • the inventors of the present invention studied an intermediate layer that is cheaper than palladium and can provide sufficient bonding force with the carbon-based particle surface. Since silver oxide is an oxide that can smoothly adhere to the surface of carbon-based particles and is known to have excellent bonding strength with metal, a technology for forming a metal coating layer after forming it as an intermediate layer has been developed.
  • the metal layer formed thereafter can be strongly bonded to the carbon-based particles, so that the bonding strength can be equal to or higher than that of the conventional case of using a layer containing palladium. knew there was
  • the characteristics of the conductive carbon-based particles are determined depending on the type of metal layer formed on the surface of the carbon-based particles. Copper has excellent electrical conductivity, but is easily oxidized, making reliability a problem. Nickel, on the other hand, has excellent corrosion resistance, but has lower electrical conductivity than copper. Silver has excellent corrosion resistance and electrical conductivity, but has a problem of high price. As such, it is difficult to satisfy all the characteristics required by the industry with only one type.
  • the inventors of the present invention first form a copper metal layer by making the metal layer a multi-layer structure, and form a nickel or silver metal layer on the copper metal layer to protect the copper metal layer, so that the multi-layer structure metal layer is formed on the surface of the conductive carbon system particles were invented.
  • a conductive carbon-based particle comprising a third layer may be provided.
  • the carbon-based particles constituting the core of the conductive carbon-based particles may be at least one selected from the group consisting of graphite, graphene, and CNT.
  • conductive carbon-based particles have low density, excellent chemical resistance, and can have various particle sizes, they are advantageous for application to various electronic parts.
  • the carbon-based particles constituting the core are graphite, graphene, or CNT, and since products with various characteristics are commercially available, products of various conductive carbon-based particles can be made by using them.
  • graphite is commercialized with various particle sizes and shapes depending on the type, such as artificial graphite and natural graphite, and various products and applications are possible because the characteristics and unit price are varied.
  • the surface of the carbon-based particles is difficult to easily combine with the metal layer due to the nature of the material. Formation of a catalyst layer is required in order to modify the surface characteristics, but in the present invention, the first layer, which is a catalyst layer containing silver oxide, is first formed instead of the conventional catalyst layer containing palladium. Since silver oxide has excellent bonding with metal as well as carbon, it is possible to maintain strong bonding between the carbon-based particles constituting the core and the metal layer on the surface.
  • the first layer including silver oxide may further include tin.
  • Tin is an element used to induce silver oxide to be smoothly attached to the surface of the carbon-based particle, and when the coating operation is performed in an aqueous solution, the carbon-based particle It adds hydrophilization of the surface and helps the attachment of the silver element to the surface of the carbon-based particle.
  • Such tin may form a first layer together with silver oxide, or may be formed between the first layer containing silver oxide and the surface of the carbon-based particle.
  • the first layer including silver oxide may further include metal silver together with the silver oxide, and when metal silver is further included, bonding with copper, which is a metal included in the second layer, may be stronger.
  • Silver oxide strengthens the bond with the carbon-based particles, and metal silver strongly bonds with the silver oxide and at the same time provides a strong bond with the same metal, copper, resulting in a bonding force between the second layer containing copper and the carbon-based particles. will further strengthen
  • the molar ratio of the silver element in the silver oxide to the silver element in the metallic silver in the first layer is preferably in the range of 1 to 20.
  • the molar ratio of the silver element in the metallic silver to the silver element in the silver oxide is preferably 1 to 20, more preferably 1 to 10 so that the ratio of the silver element in the silver oxide is higher. Measurement of this molar ratio can be measured by X-ray Photoelectron Spectroscopy (XPS).
  • the oxidation number of silver in silver oxide can be from +1 to +3, and since the oxidation number of silver in the amorphous phase may not be an integer, the oxidation number of silver in silver oxide can exceed 0 and be 3 or less.
  • the first layer may further include palladium.
  • palladium By including palladium, the bond between the surface of the carbon-based particle and the silver oxide and the bond between the second layer may be further strengthened.
  • the amount of palladium contained may be much smaller than that contained in conventional conductive carbon-based particles without silver oxide.
  • the amount of palladium used in the manufacturing process for conductive carbon-based particles is generally in the range of 100 to 1,000 ppm based on the conductive carbon-based particles, but the amount of palladium used in the conductive carbon-based particles according to the present invention exceeds 0 and is less than 50 ppm. can
  • the content of silver included in the first layer may be 10 to 1,000 ppm of the total weight of the conductive carbon-based particles.
  • the metal silver or silver oxide formed in the first layer must have a certain amount or more to provide a satisfactory bonding force to the second layer, and if it is too large, process costs increase, which is undesirable. More preferably, it may be 10 to 500 ppm.
  • the first layer may have an island shape discontinuously formed on the surface of the carbon-based particle.
  • the first layer is a layer that reinforces bonding strength with carbon-based particles to the second layer that imparts electrical conductivity, and may sufficiently provide bonding strength to the second layer even if it has a discontinuous island shape.
  • the first layer may be in the form of a continuous film, in which case the first layer occupies at least 50% of the surface area of the carbon-based particles. This is because, even in the case of a continuous film form, sufficient binding force can be provided to the second layer only when it is at least 50% or more of the particle surface area.
  • a second layer containing copper which is a metal having excellent electrical conductivity, is formed on the first layer containing silver oxide. Copper has excellent electrical conductivity among metals, so that conductive carbon-based particles have excellent electrical conductivity.
  • the second layer containing copper may be 5 to 40% by weight in the total conductive carbon-based particles. If it is less than 5% by weight, the electrical conductivity may be reduced, and if it exceeds 40% by weight, the density of the entire conductive carbon-based particles increases. , which increases the risk of the second layer falling off, which is undesirable. Therefore, the content of the second layer in the conductive carbon-based particles is preferably 5 to 30% by weight, more preferably 8 to 20% by weight.
  • the content of copper in the second layer including copper is 90% by weight or more. If the content is less than 90% by weight, the second layer has poor electrical conductivity.
  • a third layer containing nickel or silver may be formed on the second layer containing copper.
  • the third layer containing nickel or silver prevents oxidation of metallic copper formed in the second layer and simultaneously has excellent electrical conductivity, so that the conductive carbon-based particles can finally secure both electrical conductivity and reliability.
  • the third layer When a metal layer containing nickel having excellent corrosion resistance is formed as the third layer, it is possible to secure conductivity of a certain level or more as nickel, which is a metal, is formed while protecting the second layer.
  • Such a third layer may include phosphorus as well as nickel. Inclusion of phosphorus lowers electrical conductivity but improves chemical resistance and oxidation resistance. It is preferable to include phosphorus together with.
  • the content of phosphorus in the third layer is preferably 0.1 to 13.0% by weight. If it is too low, the desired improvement in chemical resistance and oxidation resistance is not achieved, and if it contains more than 13% by weight of phosphorus, sufficient electricity This is because conductivity cannot be obtained. More preferably, the content of phosphorus is 0.5 to 6% by weight.
  • the third layer may include metal silver other than nickel.
  • Silver is a metal having excellent corrosion resistance and electrical conductivity, and is ideal in terms of characteristics, but has a disadvantage in that it is expensive. Therefore, if silver having excellent electrical conductivity while protecting copper is formed as a third layer on the second layer made of copper, which is equivalent to silver in terms of electrical conductivity, reliability can be secured while minimizing the amount of expensive silver used, and conductive carbon It is possible to maximize the conductivity of the system particles.
  • hydrophilization step of hydrophilizing the surface of the carbon-based particles (b) forming a first layer of coating silver oxide on the carbon-based particles whose surfaces are hydrophilic, (c) the first A method for manufacturing conductive carbon-based particles may include forming a second layer of electrolessly plating copper on the layer and (d) forming a third layer of electroless plating of nickel or silver on the second layer.
  • a hydrophilization step of introducing a chemical functional group to the surface of the carbon-based particles to make them hydrophilic is required.
  • This hydrophilization step may be performed in an aqueous solution of a strong acid having a pH of 3 or less. This is because the chemical functional group can be smoothly attached to the surface of the carbon-based particle by partially breaking the carbon bond on the surface of the carbon-based particle through the strong acid solution. Therefore, in order to treat the surface of the stable carbon-based particles, a strong acidic atmosphere of pH 3 or less made with an inorganic acid such as sulfuric acid, nitric acid or hydrochloric acid is preferable.
  • the hydrophilization treatment of the carbon-based particles may be performed in an aqueous solution of a strong acid as described above, the carbon-based particles may be hydrophilized in a dry manner by modifying the surface of the carbon-based particles through plasma treatment.
  • Tin may be coated together with silver oxide to form a first layer containing silver oxide. Tin can increase the binding force of silver oxide on the surface of the hydrophilized carbon-based particles.
  • a tin layer may be first formed on the surface of the hydrophilized carbon-based particle, and then a first layer containing silver oxide may be formed.
  • Formation of the first layer containing silver oxide may be performed in an alkaline aqueous solution having a pH of 8 or higher. This is because silver oxide is well formed in an alkaline atmosphere of pH 8 or higher. More preferably, it may be made in an aqueous solution in the pH range of 9 to 11.
  • step (b) and before step (c) the amount of silver oxide is reduced by stirring the carbon-based particles having the first layer in an aqueous solution having a pH of 8 to 14 and a temperature of 20 to 80 ° C.
  • a post-processing step of adjusting may be further included.
  • the amount of silver oxide can be controlled by treating the silver oxide in an alkali aqueous solution at an appropriate temperature to increase the silver oxide content to a desired level.
  • the recovered graphite particles were added to an aqueous solution in which 1.5 g of stannous chloride (SnCl 2 2H 2 O) and 6 ml of hydrochloric acid (35% solution) were dissolved in 100 g of deionized water and stirred for 30 minutes to form a tin layer. The temperature of the aqueous solution was maintained at 35°C.
  • stannous chloride SnCl 2 2H 2 O
  • hydrochloric acid 35% solution
  • the temperature was maintained at 40°C and stirred for 1 hour to form a silver oxide layer. After 1 hour, it was collected by filtration, and then washed three times by stirring in 200 g of deionized water, and then recovered. A portion of the powder having the silver oxide layer was collected and surface analysis was performed through X-ray Photoelectron Spectroscopy (XPS).
  • XPS X-ray Photoelectron Spectroscopy
  • the powder formed up to the silver oxide layer was recovered, and a copper coating layer was formed using an electroless plating method.
  • An aqueous solution of copper sulfate complex was prepared with 40 g of EDTA (Ethylene-diamine-tetraacetic acid), 30 g of NaOH, and 20 g of copper sulfate as a complex in 300 g of deionized water solution, and graphite powder having a silver oxide layer was added to it. While stirring, a formaldehyde solution was used as a reducing agent. It was applied dropwise to form a coating layer containing copper.
  • EDTA Ethylene-diamine-tetraacetic acid
  • a nickel coating layer was formed again on the graphite powder on which the copper coating layer was formed .
  • the powder formed to the copper coating layer was added to the nickel plating solution prepared by adding 30 g of sodium hypophosphate and 3 ml of lead acetate, and maintained at 70 to 90 ° C. for 2 hours while stirring for electroless plating.
  • the copper coating layer was formed in the same manner as in Example 1, and then a coating layer containing silver was formed by electroless plating.
  • a silver coating solution with 300 g of deionized water, 2 g of EDTA (Ethylene-diamine-tetraacetic acid), 2.5 ml of 28% concentration ammonia water, and 3 g of silver nitrate (AgNO 3 ), graphite particles formed up to a copper coating layer were added, While stirring, a reducing solution in which 10 g of glucose and 2 g of sodium hydroxide were dissolved in 50 g of deionized water was added dropwise for 1 hour to form a third layer containing silver.
  • EDTA Ethylene-diamine-tetraacetic acid
  • AgNO 3 silver nitrate
  • Example 2 In the same manner as in Example 1, after forming the first layer containing silver oxide on the surface of the graphite particles, a post-treatment was performed in an aqueous alkali solution. For post-treatment, 28% ammonia water was added to 100 g of deionized water, maintained at 60° C., and graphite particles formed up to the first layer were added and stirred. The pH of the aqueous solution before adding the graphite particles was 10.1.
  • Example 2 In the same manner as in Example 1, a hydrophilization treatment and a tin layer were formed. Thereafter, electroless plating was performed immediately without forming a silver oxide layer to sequentially form a second layer containing copper and a third layer containing nickel. Electroless plating of copper and nickel was performed in the same manner as in Example 1.
  • Example 2 In the same manner as in Example 1, a first layer containing silver oxide was formed on the surface of the graphite particles. Thereafter, ascorbic acid is added to the aqueous solution to make some of the silver oxide on the surface into a metallic silver state, and then electroless plating is performed to sequentially form a second layer containing copper and a third layer containing nickel. formed. Electroless plating of copper and nickel was performed in the same manner as in Example 1.
  • the silver element ratio of silver oxide and metallic silver was analyzed, the silver element content, nickel content and phosphorus content were analyzed, and the coating state was observed through a scanning electron microscope (SEM). .
  • SEM scanning electron microscope
  • the silver element ratio was analyzed by taking a sample after forming the first layer and using XPS. Elemental silver content, nickel content, and phosphorus content were analyzed through an inductively coupled plasma mass spectrometer (ICP).
  • Reliability is measured by mixing a certain amount of conductive graphite particles made in Examples 1 to 3 and Comparative Examples 1 and 2 with an acrylic binder, applying them on a polyimide film, drying, maintaining the molten lead for 30 seconds, and then measuring the conductivity. It was evaluated through a reflow test.
  • the Cu content represents the weight percent occupied by the copper element based on the total conductive graphite particles.
  • FIG. 1 shows a scanning electron micrograph of conductive graphite particles according to an example.
  • 1(a) is Example 1
  • FIG. 1(b) is Example 2
  • FIG. 1(c) is Comparative Example 1
  • FIG. 1(d) is a scanning electron microscope image of a sample according to Comparative Example 2.
  • Example 2 is a result of measuring the ratio of silver elements of silver oxide and metallic silver in the first layer in the sample according to Example 3.
  • This molar ratio (Ag x+ /Ag 0 ) in Example 3 was 7.83.

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Abstract

The objective of the present invention is to provide conductive carbon-based particles having a metal layer, which is formed on the surface thereof and has excellent electrical conductivity and corrosion resistance, and excellent binding force with respect to carbon-based particles. In order to accomplish the objective, the present invention can provide conductive carbon-based particles comprising: a first layer, which is formed on carbon-based particles and comprises silver oxide; a second layer, which is formed on the first layer and comprises copper; and a third layer, which is formed on the second layer and comprises nickel or silver.

Description

내식성이 우수한 전도성 탄소계 입자Conductive carbon-based particles with excellent corrosion resistance
본 발명은 전도성 금속 코팅층을 가지는 전도성 탄소계 입자에 관한 것으로, 특히 고가의 팔라듐 촉매층 없이 구리 금속층이 표면에 형성되고 다시 구리 금속층의 보호를 위해 니켈 또는 은 코팅층이 추가로 형성되는 다층 구조의 내식성이 우수한 전도성 탄소계 입자 및 그 제조 방법에 관한 것이다.The present invention relates to conductive carbon-based particles having a conductive metal coating layer, and in particular, a copper metal layer is formed on the surface without an expensive palladium catalyst layer, and a nickel or silver coating layer is additionally formed to protect the copper metal layer. It relates to excellent conductive carbon-based particles and a manufacturing method thereof.
전도성 입자는 전자재료에서 매우 광범위하게 사용되고 있다. 그중 구리 또는 니켈과 같은 금속 입자는 높은 전도성을 가지고 있으며, 가격 경쟁력 또한 높기 때문에 많은 전자부품의 전기 전도성이 필요한 필름, 접착제, 코팅 슬러리 등에 다양하게 활용이 되고 있다.Conductive particles are widely used in electronic materials. Among them, metal particles such as copper or nickel have high conductivity and are highly competitive in price, so they are widely used in films, adhesives, and coating slurries that require electrical conductivity in many electronic parts.
그런데, 이러한 금속 입자는 합성 과정에서 다양한 크기의 입자를 제조하기 어렵고, 입자 간의 입도 균일성과 구형의 형상을 유지하기 어려워 전도성 필름이나 접착제를 제조할 때 균일한 두께의 필름 또는 접착층을 만들기 어렵게 되고, 접촉 특성도 균일하게 유지하기 어렵게 된다. 또한, 좋지 않은 접촉 특성을 보상하기 위해 금속 입자를 많은 부피로 필름 또는 접착제에 투입하게 되는데, 이러한 금속 입자에 의한 높은 부피 비율은 필름 또는 접착층을 무겁게 하고 접착력을 약화시키는 문제를 일으킬 수 있다.However, these metal particles are difficult to produce particles of various sizes in the synthesis process, and it is difficult to maintain particle size uniformity and spherical shape between particles, making it difficult to make a film or adhesive layer of uniform thickness when manufacturing a conductive film or adhesive, It also becomes difficult to keep the contact characteristics uniform. In addition, in order to compensate for poor contact properties, a large volume of metal particles is added to the film or adhesive, and a high volume ratio of the metal particles may cause problems in that the film or adhesive layer becomes heavy and the adhesive strength is weakened.
한편, 밀도가 낮고 내화학성이 우수하면서 일정 이상의 전도성을 가지는 탄소계 입자도 전도성 물질로 많이 사용되는데, 탄소계 입자로는 흑연 입자, 그래핀 입자, CNT 입자등이 가능하다. 하지만 이러한 탄소계 입자로 만들어지는 필름 또는 접착층은 여전히 금속 입자에 비해 전도성이 낮은 문제가 있다.On the other hand, carbon-based particles having a low density, excellent chemical resistance, and conductivity of a certain level or more are also widely used as a conductive material. Examples of the carbon-based particles include graphite particles, graphene particles, and CNT particles. However, the film or adhesive layer made of these carbon-based particles still has a problem in that the conductivity is lower than that of the metal particles.
이러한 문제를 극복하기 위해, 밀도가 낮고 내화학성이 우수한 흑연, 그래핀, CNT 등과 같은 탄소계 입자의 표면에 구리, 니켈, 은, 금과 같은 전도성 금속층을 형성한 전도성 탄소계 입자를 적용할 필요가 있다.In order to overcome these problems, it is necessary to apply conductive carbon-based particles in which a conductive metal layer such as copper, nickel, silver, or gold is formed on the surface of carbon-based particles such as graphite, graphene, and CNT, which have low density and excellent chemical resistance. there is
하지만, 모재인 탄소계 입자와 금속층은 서로 다른 이종 물질로서 결합력을 유지하기 어려운 문제가 있다. 통상적으로 탄소계 물질이나 세라믹과 같은 이종 물질의 표면에 금속 코팅층을 형성하기 위해서는 팔라듐을 이용한 촉매층을 형성한 후 금속층을 형성하는 방법이 많이 사용되는데, 팔라듐은 너무 고가이어서 공정 비용이 증가하게 되는 문제가 있게 된다.However, since the base material carbon-based particles and the metal layer are different materials, it is difficult to maintain bonding strength. In general, in order to form a metal coating layer on the surface of a heterogeneous material such as a carbon-based material or ceramic, a method of forming a metal layer after forming a catalyst layer using palladium is often used, but palladium is too expensive, so the process cost increases. there will be
한편, 탄소계 입자의 표면에 코팅되는 금속층은 다양한 금속으로 이루어질 수 있는데, 구리는 전도성이 은에 가까울 정도로 우수하지만, 쉽게 산화되는 문제가 있고, 니켈은 내식성은 우수하기 때문에 장기 신뢰성 등에서 장점이 있지만 전기 전도도가 낮은 문제가 있다. 또 다른 금속인 은(Ag)은 전도성과 내식성이 모두 우수하지만 가격이 너무 높다는 문제가 있다. On the other hand, the metal layer coated on the surface of the carbon-based particles may be made of various metals. Copper has excellent conductivity close to silver, but has a problem of being easily oxidized, and nickel has excellent corrosion resistance, so it has advantages in long-term reliability, etc. There is a problem of low electrical conductivity. Another metal, silver (Ag), is excellent in both conductivity and corrosion resistance, but has a problem in that its price is too high.
이처럼 탄소계 입자의 표면에 형성되는 금속층 또한 원하는 품질을 모두 만족하기 어려운 점이 있다. As such, it is difficult for the metal layer formed on the surface of the carbon-based particles to satisfy all desired qualities.
본 발명은 표면에 전기 전도성이 우수하면서 동시에 내식성과 탄소계 입자와의 결합력이 우수한 금속층이 형성된 전도성 탄소계 입자를 제공하는 것을 목적으로 한다. An object of the present invention is to provide conductive carbon-based particles having a metal layer having excellent electrical conductivity and at the same time excellent corrosion resistance and bonding strength with carbon-based particles formed on the surface of the conductive carbon-based particles.
본 발명의 또 다른 목적은 전도성 탄소계 입자 표면에 전기 전도성이 우수하면서 동시에 내식성과 탄소계 입자와의 결합력이 우수한 금속층을 저가에 형성할 수 있는 전도성 탄소계 입자 제조 방법을 제공하는 것이다.Another object of the present invention is to provide a method for manufacturing conductive carbon-based particles capable of forming a metal layer having excellent electrical conductivity and excellent corrosion resistance and bonding strength with carbon-based particles on the surface of the conductive carbon-based particles at low cost.
상기와 같은 목적을 달성하기 위해, 본 발명에서는 탄소계 입자 표면에 형성되는 산화은을 포함하는 제 1 층과 상기 제 1 층 위에 형성되면서 구리를 포함하는 제 2 층 및 상기 제 2 층 위에 형성되며 니켈 또는 은을 포함하는 제 3 층을 포함하는 전도성 탄소계 입자를 제공할 수 있다. In order to achieve the above object, in the present invention, a first layer containing silver oxide formed on the surface of carbon-based particles, a second layer containing copper while being formed on the first layer, and nickel formed on the second layer Alternatively, conductive carbon-based particles including a third layer including silver may be provided.
또한, 상기 탄소계 입자는 흑연, 그래핀 및 CNT로 이루어지는 군에서 선택되는 일종 이상일 수 있다. In addition, the carbon-based particles may be one or more selected from the group consisting of graphite, graphene, and CNT.
또한, 상기 제 1 층은 금속 은을 더 포함하고, 상기 금속 은에서 은 원소에 대한 상기 산화은에서 은 원소의 몰 비율(Agx+/Ag0 ( 0< x ≤3 ))이 1 ~ 20범위일 수 있다. In addition, the first layer further includes metallic silver, and the molar ratio of the silver element in the silver oxide to the silver element in the metallic silver (Ag x + /Ag 0 ( 0 < x ≤ 3 )) is in the range of 1 to 20 can
또한, 상기 제 1 층은 주석을 더 포함할 수 있다. In addition, the first layer may further include tin.
또한, 상기 제 1 층에 포함되는 은의 함량은, 상기 전도성 탄소계 입자 전체 중량의 10~1,000 ppm일 수 있다. In addition, the content of silver included in the first layer may be 10 to 1,000 ppm of the total weight of the conductive carbon-based particles.
또한, 상기 제 3 층은 상기 니켈과 함께 인을 더 포함할 수 있다. In addition, the third layer may further include phosphorus together with the nickel.
또한, 상기 제 3 층은 0.1~13.0 중량%의 인을 포함할 수 있다. In addition, the third layer may include 0.1 to 13.0% by weight of phosphorus.
본 발명에 따른 전도성 탄소계 입자의 제조 방법은, (a) 탄소계 입자의 표면을 친수화 시키는 친수화 단계, (b) 상기 표면이 친수화된 탄소계 입자에 산화은을 코팅하는 제 1 층 형성 단계, (c) 상기 제 1 층 위에 구리를 무전해 도금하는 제 2 층 형성단계 및 (d) 상기 제 2 층 위에 니켈 또는 은을 무전해 도금하는 제 3 층 형성단계를 포함할 수 있다. The method for manufacturing conductive carbon-based particles according to the present invention includes (a) a hydrophilization step of hydrophilizing the surface of carbon-based particles, (b) forming a first layer of coating silver oxide on carbon-based particles whose surfaces are hydrophilized (c) forming a second layer of electrolessly plating copper on the first layer; and (d) forming a third layer of electroless plating of nickel or silver on the second layer.
또한, 상기 (a)단계와 (b)단계 사이에, 주석층을 형성하는 단계를 더 포함할 수 있다. In addition, between steps (a) and (b), a step of forming a tin layer may be further included.
또한, 상기 (b)단계 후 상기 (c)단계 전에, pH 8~14이고, 온도 20~80℃인 수용액에서 상기 제 1 층이 형성된 탄소계 입자를 교반하여 상기 산화은 양을 조절하는 후처리 단계를 더 포함할 수 있다. In addition, after the step (b) and before the step (c), a post-treatment step of adjusting the amount of silver oxide by stirring the carbon-based particles having the first layer in an aqueous solution having a pH of 8 to 14 and a temperature of 20 to 80 ° C. may further include.
본 발명에 따른 전도성 탄소계 입자는 저가이면서 전기 전도도와 내식성이 우수하여 전기 전도도가 필요한 다양한 전자부품에 적용이 가능하고, 표면 금속층의 결합력이 우수하여 적용되는 부품의 경량화와 전도성 및 신뢰성 향상을 이룰 수 있게 된다. The conductive carbon-based particles according to the present invention are inexpensive and have excellent electrical conductivity and corrosion resistance, so that they can be applied to various electronic parts that require electrical conductivity, and the bonding strength of the surface metal layer is excellent, so that the applied parts can be reduced in weight and improved in conductivity and reliability. be able to
또한, 본 발명에서 제공하는 전도성 탄소계 입자 제조 방법을 통해 저가의 공정을 통해 전도성과 신뢰성이 우수한 전도성 탄소계 입자의 대량 생산이 가능하게 된다. In addition, the method for manufacturing conductive carbon-based particles provided in the present invention enables mass production of conductive carbon-based particles having excellent conductivity and reliability through a low-cost process.
도 1은 본 발명에 따른 실시예와 비교예에 따른 전도성 탄소계 입자의 주사전자현미경 이미지이다.1 is a scanning electron microscope image of conductive carbon-based particles according to Examples according to the present invention and Comparative Examples.
도 2는 본 발명에 따른 일 실시예에서의 전도성 탄소계 입자에 대한 X-선 광전자분광법(X-ray Photoelectron Spectroscopy, XPS)에 따른 분석 결과를 나타낸다. Figure 2 shows the analysis results according to the X-ray photoelectron spectroscopy (XPS) for the conductive carbon-based particles in one embodiment according to the present invention.
이하 본 발명의 실시예에 대하여 첨부된 도면을 참고로 그 구성 및 작용을 설명하기로 한다. 하기에서 본 발명을 설명함에 있어, 관련된 공지 기능 또는 구성에 대한 구체적인 설명이 본 발명의 요지를 불필요하게 흐릴 수 있다고 판단되는 경우에는 그 상세한 설명을 생략할 것이다. 또한, 어떤 부분이 어떤 구성요소를 '포함'한다고 할 때, 이는 특별히 반대되는 기재가 없는 한 다른 구성요소를 제외하는 것이 아니라 다른 구성요소를 더 포함할 수 있는 것을 의미한다.Hereinafter, the configuration and operation of embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, when a certain part 'includes' a certain component, this means that it may further include other components without excluding other components unless otherwise stated.
탄소계 입자는 내화학성이 우수하고 밀도가 낮은 장점이 있지만 전기전도성은 높지 않아 전도성 입자로 사용하기에 제한이 있다. 이를 극복하기 위해 표면에 전도성 금속층을 형성하면 다양한 형상과 크기의 탄소계 입자에 전도성을 부여할 수 있게 된다.Carbon-based particles have the advantages of excellent chemical resistance and low density, but their use as conductive particles is limited because their electrical conductivity is not high. To overcome this, if a conductive metal layer is formed on the surface, conductivity can be imparted to carbon-based particles of various shapes and sizes.
그러나 탄소와 금속은 이종재료로서 그 접착력이 매우 낮기 때문에 금속층이 탄소계 입자의 표면에 형성되기는 매우 어렵다. 이를 극복하기 위해서 종래에는 전도성을 부여하는 금속층과 탄소계 입자 사이에 접착을 원활하게 할 수 있는 중간층을 형성하는 방법을 사용하는데, 이러한 중간층으로서 팔라듐을 포함하는 촉매층을 형성시켰다. 이러한 팔라듐 촉매층은 금속층인 구리, 니켈, 은 등의 원활한 형성을 유도하였다. 하지만, 잘 알려진 바와 같이 팔라듐은 고가의 귀금속으로서 최근에는 금보다도 비싸기 때문에 이를 사용하여 만들기에는 공정 비용이 너무 높아지는 문제가 있다. However, since carbon and metal are heterogeneous materials and have very low adhesion, it is very difficult to form a metal layer on the surface of the carbon-based particles. In order to overcome this, conventionally, a method of forming an intermediate layer capable of facilitating adhesion between a metal layer for imparting conductivity and carbon-based particles is used, and a catalyst layer containing palladium is formed as such an intermediate layer. Such a palladium catalyst layer led to smooth formation of metal layers such as copper, nickel, and silver. However, as is well known, since palladium is an expensive precious metal and is more expensive than gold recently, there is a problem in that the process cost is too high to make it using it.
이러한 문제를 해결하기 위해서 본 발명의 발명자들은 팔라듐 보다 저가이면서 탄소계 입자 표면과 충분한 결합력을 제공할 수 있는 중간층을 검토하였다. 산화은은 산화물로서 탄소계 입자의 표면에 원활하게 접착이 가능하면서 동시에 금속과의 결합력도 우수한 것으로 알려져 있기 때문에 이를 중간층으로 형성한 후 금속 코팅층을 형성하는 기술의 개발을 진행하였다.In order to solve this problem, the inventors of the present invention studied an intermediate layer that is cheaper than palladium and can provide sufficient bonding force with the carbon-based particle surface. Since silver oxide is an oxide that can smoothly adhere to the surface of carbon-based particles and is known to have excellent bonding strength with metal, a technology for forming a metal coating layer after forming it as an intermediate layer has been developed.
그 결과 산화은 단독 또는 산화은과 금속 은이 복합화된 중간층이 형성된 경우 이후 형성되는 금속층이 탄소계 입자와 강하게 결합될 수 있어서, 종래의 팔라듐을 포함하는 층을 이용한 경우와 비교해 동등하거나 그 이상의 결합력을 나타낼 수 있는 것을 알 수 있었다.As a result, when silver oxide alone or an intermediate layer in which silver oxide and metallic silver are combined is formed, the metal layer formed thereafter can be strongly bonded to the carbon-based particles, so that the bonding strength can be equal to or higher than that of the conventional case of using a layer containing palladium. knew there was
한편, 탄소계 입자의 표면에 형성되는 금속층의 종류에 따라 전도성 탄소계 입자의 특성이 결정되는데, 구리는 전기 전도성이 우수한 반면에 산화가 쉽게 되어 신뢰성이 문제가 된다. 니켈은 반대로 내식성이 우수하지만 전기 전도성은 구리보다 낮은 문게가 있다. 은은 내식성과 전기 전도도가 모두 우수하지만 가격이 높은 문제가 있다. 이처럼 어느 한 종류만으로는 산업에서 요구하는 특성을 모두 만족시키기 어려운 점이 있다. On the other hand, the characteristics of the conductive carbon-based particles are determined depending on the type of metal layer formed on the surface of the carbon-based particles. Copper has excellent electrical conductivity, but is easily oxidized, making reliability a problem. Nickel, on the other hand, has excellent corrosion resistance, but has lower electrical conductivity than copper. Silver has excellent corrosion resistance and electrical conductivity, but has a problem of high price. As such, it is difficult to satisfy all the characteristics required by the industry with only one type.
이러한 문제를 극복하기 위해 본 발명의 발명자들은 금속층을 다층 구조로 하여 우선 구리 금속층을 형성하고 이러한 구리 금속층을 보호하기 위해 니켈 또는 은 금속층을 구리 금속층 위에 형성함으로써 다층 구조의 금속층이 표면에 형성된 전도성 탄소계 입자를 발명하게 되었다. In order to overcome this problem, the inventors of the present invention first form a copper metal layer by making the metal layer a multi-layer structure, and form a nickel or silver metal layer on the copper metal layer to protect the copper metal layer, so that the multi-layer structure metal layer is formed on the surface of the conductive carbon system particles were invented.
이에 따라, 본 발명에서는 탄소계 입자 표면에 형성되는 산화은을 포함하는 제 1 층과, 상기 제 1 층 위에 형성되면서 구리를 포함하는 제 2 층 및 상기 제 2 층 위에 형성되며 니켈 또는 은을 포함하는 제 3 층을 포함하는 전도성 탄소계 입자를 제공할 수 있다. Accordingly, in the present invention, a first layer containing silver oxide formed on the surface of carbon-based particles, a second layer formed on the first layer and containing copper, and a second layer formed on the second layer and containing nickel or silver A conductive carbon-based particle comprising a third layer may be provided.
전도성 탄소계 입자의 코어를 이루는 탄소계 입자는 흑연, 그래핀 및 CNT로 이루어지는 군에서 선택되는 일종 이상일 수 있다. The carbon-based particles constituting the core of the conductive carbon-based particles may be at least one selected from the group consisting of graphite, graphene, and CNT.
전도성 탄소계 입자는 밀도가 낮으면서 내화학성이 우수하고 다양한 입도를 가질 수 있기 때문에 여러 전자 부품에 적용되기에 유리하다. 이를 위해 코어를 이루는 탄소계 입자는 흑연, 그래핀 또는 CNT인 것이 바람직한데, 이들은 모두 다양한 특성의 제품이 상용화되어 있어서 이들을 이용하면 다양한 전도성 탄소계 입자의 제품을 만들 수 있게 된다. 특히, 흑연은 인조 흑연, 천연 흑연 등 종류에 따라 다양한 입도와 형상의 제품이 상용화되어 있고 특성과 단가가 다양하기 때문에 다양한 제품화와 적용이 가능하게 된다.Since conductive carbon-based particles have low density, excellent chemical resistance, and can have various particle sizes, they are advantageous for application to various electronic parts. To this end, it is preferable that the carbon-based particles constituting the core are graphite, graphene, or CNT, and since products with various characteristics are commercially available, products of various conductive carbon-based particles can be made by using them. In particular, graphite is commercialized with various particle sizes and shapes depending on the type, such as artificial graphite and natural graphite, and various products and applications are possible because the characteristics and unit price are varied.
상술한 바와 같이 탄소계 입자의 표면은 재료의 특성상 쉽게 금속층과 결합하기 어렵다. 이러한 표면 특성을 개질하기 위해서 촉매층의 형성이 필요한데, 본 발명에서는 종래의 팔라듐을 포함하는 촉매층이 아니라 산화은을 포함하는 촉매층인 제 1 층을 먼저 형성하게 된다. 산화은은 탄소뿐만 아니라 금속과의 결합도 우수하기 때문에 코어를 이루는 탄소계 입자와 표면의 금속층간의 결합이 강하게 유지되도록 할 수 있다. As described above, the surface of the carbon-based particles is difficult to easily combine with the metal layer due to the nature of the material. Formation of a catalyst layer is required in order to modify the surface characteristics, but in the present invention, the first layer, which is a catalyst layer containing silver oxide, is first formed instead of the conventional catalyst layer containing palladium. Since silver oxide has excellent bonding with metal as well as carbon, it is possible to maintain strong bonding between the carbon-based particles constituting the core and the metal layer on the surface.
본 발명에서, 산화은을 포함하는 제 1 층은 주석을 더 포함할 수 있는데, 주석은 산화은이 원활하게 탄소계 입자 표면에 부착되도록 유도하기 위해 사용되는 원소로 수용액에서 코팅 작업을 진행하는 경우 탄소계 입자 표면의 친수화를 더해 주고 은 원소의 탄소계 입자 표면으로의 부착을 돕게 된다. 이러한 주석은 산화은과 함께 제 1 층을 이룰 수도 있고, 산화은을 포함하는 제 1 층과 탄소계 입자 표면 사이에 형성될 수도 있다. In the present invention, the first layer including silver oxide may further include tin. Tin is an element used to induce silver oxide to be smoothly attached to the surface of the carbon-based particle, and when the coating operation is performed in an aqueous solution, the carbon-based particle It adds hydrophilization of the surface and helps the attachment of the silver element to the surface of the carbon-based particle. Such tin may form a first layer together with silver oxide, or may be formed between the first layer containing silver oxide and the surface of the carbon-based particle.
본 발명에서 산화은을 포함하는 제 1 층은 산화은과 함께 금속 은을 더 포함할 수 있는데, 금속 은이 더 포함되면 제 2 층에 포함되는 금속인 구리와의 결합을 보다 더 강하게 할 수 있다. 산화은은 탄소계 입자와의 결합을 강하게 하고, 금속 은은 이러한 산화은과의 강하게 결합되면서 동시에 같은 금속인 구리와의 강한 결합을 제공함으로써 결과적으로 구리를 포함하는 제 2 층과 탄소계 입자와의 결합력을 더 강화시키게 된다.In the present invention, the first layer including silver oxide may further include metal silver together with the silver oxide, and when metal silver is further included, bonding with copper, which is a metal included in the second layer, may be stronger. Silver oxide strengthens the bond with the carbon-based particles, and metal silver strongly bonds with the silver oxide and at the same time provides a strong bond with the same metal, copper, resulting in a bonding force between the second layer containing copper and the carbon-based particles. will further strengthen
이때, 제 1 층에서 금속 은의 은 원소에 대한 산화은에서의 은 원소의 몰 비율(Agx+/Ag0 ( 0< x ≤3 ))은 1~20범위인 것이 바람직하다. At this time, the molar ratio of the silver element in the silver oxide to the silver element in the metallic silver in the first layer (Ag x+ /Ag 0 ( 0 < x ≤ 3 )) is preferably in the range of 1 to 20.
상술한 바와 같이 금속 은을 포함하는 것이 산화은을 포함하는 제 1 층과 구리를 포함하는 제 2 층의 결합을 강하게 하지만, 산화은에서의 은 원소에 비해 금속 은에서의 은 원소의 비율이 너무 높으면 그만큼 산화은을 통한 제 1 층의 탄소계 입자 표면과의 결합력이 낮아지기 때문에 바람직하지 않다. 따라서, 산화은의 은 원소에 대한 금속 은에서의 은 원소의 몰 비율은 산화은에서의 은 원소의 비율이 더 높도록 1~20인 것이 바람직하고, 보다 바람직하게는 1~10이다. 이러한 몰 비율의 측정은 X선 광전자 분광법(X-ray Photoelectron Spectroscopy, XPS)으로 측정될 수 있다.As described above, although the inclusion of metallic silver strengthens the bond between the first layer containing silver oxide and the second layer containing copper, if the ratio of the silver element in the metallic silver compared to the silver element in the silver oxide is too high, This is not preferable because the binding force of the first layer with the surface of the carbon-based particles through the silver oxide is lowered. Therefore, the molar ratio of the silver element in the metallic silver to the silver element in the silver oxide is preferably 1 to 20, more preferably 1 to 10 so that the ratio of the silver element in the silver oxide is higher. Measurement of this molar ratio can be measured by X-ray Photoelectron Spectroscopy (XPS).
여기서, 산화은에서 은의 산화수는 +1 ~ +3까지 가능하고, 비정질상에서는 산화수가 정수가 아닐 수도 있기 때문에 산화은에서 은의 산화수는 0을 초과하면서 3이하일 수 있게 된다.Here, the oxidation number of silver in silver oxide can be from +1 to +3, and since the oxidation number of silver in the amorphous phase may not be an integer, the oxidation number of silver in silver oxide can exceed 0 and be 3 or less.
또한, 제 1 층은 팔라듐을 더 포함할 수 있는데, 팔라듐을 포함함으로써 탄소계 입자 표면과 산화은의 결합 및 제 2 층의 결합을 더 강하게 할 수 있다. 이때포함되는 팔라듐은 산화은이 없는 종래의 전도성 탄소계 입자에 포함되는 양 보다 훨씬 적게될 수 있다. 예를 들어 종래에는 전도성 탄소계 입자에 제조 공정에서 사용되는 팔라듐의 양은 전도성 탄소계 입자 기준으로 일반적으로 100~1,000 ppm범위이지만 본 발명에 따르는 전도성 탄소계 입자에는 0을 초과하면서 50 ppm 이하로 사용될 수 있다. In addition, the first layer may further include palladium. By including palladium, the bond between the surface of the carbon-based particle and the silver oxide and the bond between the second layer may be further strengthened. In this case, the amount of palladium contained may be much smaller than that contained in conventional conductive carbon-based particles without silver oxide. For example, conventionally, the amount of palladium used in the manufacturing process for conductive carbon-based particles is generally in the range of 100 to 1,000 ppm based on the conductive carbon-based particles, but the amount of palladium used in the conductive carbon-based particles according to the present invention exceeds 0 and is less than 50 ppm. can
또한, 제 1 층에 포함되는 은의 함량은 상기 전도성 탄소계 입자 전체 중량의 10~1,000 ppm 일 수 있다.In addition, the content of silver included in the first layer may be 10 to 1,000 ppm of the total weight of the conductive carbon-based particles.
제 1 층에 형성되는 금속 은 또는 산화은은 일정 함량 이상이어야 제 2 층에만족할 만한 결합력을 제공할 수 있고, 너무 많으면 공정 비용이 높아지기 때문에 바람직하지 않기 때문이다. 보다 바람직하게는 10~500 ppm일 수 있다.This is because the metal silver or silver oxide formed in the first layer must have a certain amount or more to provide a satisfactory bonding force to the second layer, and if it is too large, process costs increase, which is undesirable. More preferably, it may be 10 to 500 ppm.
또한, 본 발명에서 제 1 층은 탄소계 입자 표면에 불연속적으로 형성되는 아일랜드 형태일 수 있다. 제 1 층은 전기 전도성을 부여하는 제 2 층에 탄소계 입자와의 결합력을 강화시키는 층으로서 불연속적인 아일랜드 형태이어도 충분히 제 2 층에 결합력을 제공할 수 있다.Also, in the present invention, the first layer may have an island shape discontinuously formed on the surface of the carbon-based particle. The first layer is a layer that reinforces bonding strength with carbon-based particles to the second layer that imparts electrical conductivity, and may sufficiently provide bonding strength to the second layer even if it has a discontinuous island shape.
한편, 제 1 층은 연속적인 필름 형태일 수도 있는데, 이 경우 제 1 층은 탄소계 입자 표면적의 최소 50% 이상을 차지하게 된다. 연속적 필름 형태인 경우에도 적어도 입자 표면적의 50%이상이어야 충분한 결합력을 제 2 층에 제공할 수 있기 때문이다.Meanwhile, the first layer may be in the form of a continuous film, in which case the first layer occupies at least 50% of the surface area of the carbon-based particles. This is because, even in the case of a continuous film form, sufficient binding force can be provided to the second layer only when it is at least 50% or more of the particle surface area.
산화은을 포함하는 제 1 층 위에는 전기 전도성이 우수한 금속인 구리를 포함하는 제 2 층이 형성된다. 구리는 금속 중 특히 전기 전도성이 우수한 특성을 가지고 있어서 전도성 탄소계 입자가 우수한 전기 전도성을 가지도록 한다. A second layer containing copper, which is a metal having excellent electrical conductivity, is formed on the first layer containing silver oxide. Copper has excellent electrical conductivity among metals, so that conductive carbon-based particles have excellent electrical conductivity.
이러한 구리를 포함하는 제 2 층은 전체 전도성 탄소계 입자에서 5 ~ 40 중량%일 수 있는데 5 중량% 미만이면 전기 전도성이 떨어질 수 있고, 40 중량%를 초과하면 전체 전도성 탄소계 입자의 밀도가 높아지고, 제 2 층의 탈락 위험이 증가하여 바람직하지 않다. 따라서, 전도성 탄소계 입자에서 제 2 층의 함량은 바람직하게는 5~30 중량%, 더 바람직하게는 8~20 중량%이다.The second layer containing copper may be 5 to 40% by weight in the total conductive carbon-based particles. If it is less than 5% by weight, the electrical conductivity may be reduced, and if it exceeds 40% by weight, the density of the entire conductive carbon-based particles increases. , which increases the risk of the second layer falling off, which is undesirable. Therefore, the content of the second layer in the conductive carbon-based particles is preferably 5 to 30% by weight, more preferably 8 to 20% by weight.
한편, 본 발명에서 구리를 포함하는 제 2 층에서 구리의 함량은 90 중량%이상인데 90 중량% 미만이면 제 2 층의 전기 전도성이 떨어지기 때문이다. Meanwhile, in the present invention, the content of copper in the second layer including copper is 90% by weight or more. If the content is less than 90% by weight, the second layer has poor electrical conductivity.
본 발명에서 구리를 포함하는 제 2 층 위에는 다시 니켈 또는 은을 포함하는 제 3 층이 형성될 수 있다. In the present invention, a third layer containing nickel or silver may be formed on the second layer containing copper.
이러한 니켈 또는 은을 포함하는 제 3 층은 제 2 층에서 형성된 금속 구리의 산화를 방지하면서 동시에 우수한 전기 전도성을 가지게 됨으로써 최종적으로 전도성 탄소계 입자가 전기 전도성과 신뢰성을 모두 확보할 수 있도록 한다. The third layer containing nickel or silver prevents oxidation of metallic copper formed in the second layer and simultaneously has excellent electrical conductivity, so that the conductive carbon-based particles can finally secure both electrical conductivity and reliability.
제 3 층으로 내식성이 우수한 니켈을 포함하는 금속층이 형성되면 제 2 층을 보호하면서 한편으로 금속인 니켈이 형성됨에 따라 일정 수준 이상의 전도도를 확보할 수 있게 된다. When a metal layer containing nickel having excellent corrosion resistance is formed as the third layer, it is possible to secure conductivity of a certain level or more as nickel, which is a metal, is formed while protecting the second layer.
이러한 제 3 층은 니켈뿐만 아니라 인을 포함할 수 있는데, 인이 포함됨으로써 전기 전도도는 다소 낮아지지만 내화학성과 내산화성의 향상이 이루어지기 때문에 신뢰성이 중요한 부품에 사용되는 경우에는 제 3 층에 니켈과 함께 인을 포함하는 것이 바람직하다. 인을 포함하는 경우, 제 3 층에서 인의 함량은 0.1~13.0 중량%인 것이 바람직한데, 너무 낮으면 원하는 내화학성과 내산화성의 향상이 이루어지지 않고, 13 중량%를 넘는 인을 포함하면 충분한 전기 전도성을 얻을 수 없기 때문이다. 보다 바람직하게 인의 함량은 0.5~6 중량%이다.Such a third layer may include phosphorus as well as nickel. Inclusion of phosphorus lowers electrical conductivity but improves chemical resistance and oxidation resistance. It is preferable to include phosphorus together with. In the case of containing phosphorus, the content of phosphorus in the third layer is preferably 0.1 to 13.0% by weight. If it is too low, the desired improvement in chemical resistance and oxidation resistance is not achieved, and if it contains more than 13% by weight of phosphorus, sufficient electricity This is because conductivity cannot be obtained. More preferably, the content of phosphorus is 0.5 to 6% by weight.
한편, 제 3 층은 니켈이 아닌 금속 은을 포함할 수 있는데, 은은 내식성과 전기전도성이 모두 우수한 금속으로 특성면에서는 이상적이지만 가격이 높은 단점이 있다. 따라서 전기 전도성 면에서는 은과 동등 수준인 구리로 이루어지는 제 2 층 위에 구리를 보호하면서 우수한 전기 전도성을 가지는 은을 제 3 층으로 형성하면, 값 비싼 은의 사용량을 최소화하면서 신뢰성을 확보할 수 있고 전도성 탄소계 입자의 전도성을 극대화할 수 있게 된다. Meanwhile, the third layer may include metal silver other than nickel. Silver is a metal having excellent corrosion resistance and electrical conductivity, and is ideal in terms of characteristics, but has a disadvantage in that it is expensive. Therefore, if silver having excellent electrical conductivity while protecting copper is formed as a third layer on the second layer made of copper, which is equivalent to silver in terms of electrical conductivity, reliability can be secured while minimizing the amount of expensive silver used, and conductive carbon It is possible to maximize the conductivity of the system particles.
또한, 본 발명에서는 (a) 탄소계 입자의 표면을 친수화 시키는 친수화 단계, (b) 상기 표면이 친수화된 탄소계 입자에 산화은을 코팅하는 제 1 층 형성 단계, (c) 상기 제 1 층 위에 구리를 무전해 도금하는 제 2 층 형성단계 및 (d) 상기 제 2 층 위에 니켈 또는 은을 무전해 도금하는 제 3 층 형성단계를 포함하는 전도성 탄소계 입자 제조 방법을 제공할 수 있다. In addition, in the present invention, (a) hydrophilization step of hydrophilizing the surface of the carbon-based particles, (b) forming a first layer of coating silver oxide on the carbon-based particles whose surfaces are hydrophilic, (c) the first A method for manufacturing conductive carbon-based particles may include forming a second layer of electrolessly plating copper on the layer and (d) forming a third layer of electroless plating of nickel or silver on the second layer.
전도성 탄소계 입자를 제조하기 위해서는 우선 탄소계 입자의 표면에 화학 기능기를 도입하여 친수화시키는 친수화 단계가 필요하다. 이러한 친수화 단계는 pH 3 이하의 강산 수용액에서 이루어질 수 있다. 강산 용액을 통해 탄소계 입자 표면의 탄소 결합을 일부 끊어 줌으로써 탄소계 입자 표면에 화학 기능기가 부착이 원활하도록 할 수 있기 때문이다. 따라서 안정된 탄소계 입자의 표면을 처리하기 위해서는 황산, 질산 또는 염산과 같은 무기산에 의해 만들어지는 pH 3 이하의 강산 분위기가 바람직하다.In order to manufacture conductive carbon-based particles, first, a hydrophilization step of introducing a chemical functional group to the surface of the carbon-based particles to make them hydrophilic is required. This hydrophilization step may be performed in an aqueous solution of a strong acid having a pH of 3 or less. This is because the chemical functional group can be smoothly attached to the surface of the carbon-based particle by partially breaking the carbon bond on the surface of the carbon-based particle through the strong acid solution. Therefore, in order to treat the surface of the stable carbon-based particles, a strong acidic atmosphere of pH 3 or less made with an inorganic acid such as sulfuric acid, nitric acid or hydrochloric acid is preferable.
한편, 탄소계 입자의 친수화 처리는 상술한 바와 같이 강산의 수용액 상에서 이루어질 수 있지만, 플라즈마 처리를 통해 탄소계 입자의 표면을 개질함으로써 건식으로 친수화할 수도 있다. Meanwhile, although the hydrophilization treatment of the carbon-based particles may be performed in an aqueous solution of a strong acid as described above, the carbon-based particles may be hydrophilized in a dry manner by modifying the surface of the carbon-based particles through plasma treatment.
친수화 처리 이후에는 산화은을 포함하는 제 1 층을 형성하는데 산화은과 함께 주석을 함께 코팅할 수 있다. 주석은 친수화된 탄소계 입자의 표면에서 산화은의 결합력을 높여줄 수 있게 된다.After the hydrophilization treatment, tin may be coated together with silver oxide to form a first layer containing silver oxide. Tin can increase the binding force of silver oxide on the surface of the hydrophilized carbon-based particles.
또한, 보다 정밀한 제어를 위해서 친수화된 탄소계 입자 표면에 주석층을 먼저 형성한 후 산화은을 포함하는 제 1 층을 형성할 수 있다. In addition, for more precise control, a tin layer may be first formed on the surface of the hydrophilized carbon-based particle, and then a first layer containing silver oxide may be formed.
산화은을 포함하는 제 1 층의 형성은 pH 8이상의 알칼리 수용액에서 이루어질 수 있다. 산화은은 pH 8 이상의 알칼리 분위기에서 잘 형성되기 때문이다. 보다 바람직하게는 pH 9~11 범위의 수용액에서 이루어질 수 있다. Formation of the first layer containing silver oxide may be performed in an alkaline aqueous solution having a pH of 8 or higher. This is because silver oxide is well formed in an alkaline atmosphere of pH 8 or higher. More preferably, it may be made in an aqueous solution in the pH range of 9 to 11.
또한, 전도성 탄소계 입자 제조 방법에서, (b) 단계 이후 (c) 단계 전에 pH 8~14 이고, 온도 20~80℃인 수용액에서 상기 제 1 층이 형성된 탄소계 입자를 교반하여 상기 산화은 양을 조절하는 후처리 단계를 더 포함할 수 있다.In addition, in the conductive carbon-based particle manufacturing method, after step (b) and before step (c), the amount of silver oxide is reduced by stirring the carbon-based particles having the first layer in an aqueous solution having a pH of 8 to 14 and a temperature of 20 to 80 ° C. A post-processing step of adjusting may be further included.
수용액 중에서 제 1 층을 형성하는 경우 수용액 중의 은 이온이 환원되어 산화은이 아닌 금속 은으로 탄소계 입자 표면에 부착될 수 있다. 이러한 금속 은의 비율이 너무 높아지면 탄소계 입자 및 제 1 층과의 결합력이 낮아질 수 있기 때문에 바람직하지 않다. 따라서, 산화은의 함량을 원하는 수준으로 높이기 위해 적절한 온도의 알칼리 수용액에서 처리함으로써 산화은의 양을 조절할 수 있다.When the first layer is formed in an aqueous solution, silver ions in the aqueous solution are reduced and attached to the surface of the carbon-based particle as metallic silver rather than silver oxide. If the ratio of the metal silver is too high, it is not preferable because bonding strength between the carbon-based particles and the first layer may be lowered. Therefore, the amount of silver oxide can be controlled by treating the silver oxide in an alkali aqueous solution at an appropriate temperature to increase the silver oxide content to a desired level.
이렇게 산화은 양을 조절한 후 전도성을 가지는 구리를 포함하는 제 2 층을 형성함으로써 전도성을 부여하는 금속 코팅층과 탄소계 입자와의 결합력이 우수한 전도성 탄소계 입자를 제공할 수 있게 된다.In this way, by adjusting the amount of silver oxide and forming a second layer containing copper having conductivity, it is possible to provide conductive carbon-based particles having excellent bonding strength between the metal coating layer providing conductivity and the carbon-based particles.
이하, 본 발명을 충분히 이해하기 위해서 본 발명의 바람직한 실시예를 첨부Hereinafter, preferred embodiments of the present invention are attached in order to fully understand the present invention.
도면을 참조하여 설명한다.It demonstrates with reference to drawings.
본 발명의 실시예는 당해 기술 분야에서 통상의 지식을 가진 자에게 본 발명을 더욱 완전하게 설명하기 위하여 제공되는 것이며, 아래의 실시예는 여러 가지 다른 형태로 변형될 수 있으며, 본 발명의 범위가 아래의 실시예로 한정되는 것은 아니다. 오히려, 이들 실시예는 본 개시를 더욱 충실하고 완전하게 하며 당업자에게 본 발명의 사상을 완전하게 전달하기 위하여 제공되는 것이다.The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and the following examples may be modified in many different forms, and the scope of the present invention It is not limited to the examples below. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the spirit of the invention to those skilled in the art.
[실시예 1][Example 1]
탈이온수 100g에 염산(35% 용액) 3g 을 투입하고 60℃로 승온하였다. 여기에 D50 20㎛인 그라파이트 10g을 투입하고 교반하면서 10시간 유지하여 흑연 분말의 표면을 친수화하였다. 이후 친수화된 흑연 분말을 회수하고 다시 탈이온수 100g에서 교반하여 3회 세정한 후 회수하였다.3 g of hydrochloric acid (35% solution) was added to 100 g of deionized water and the temperature was raised to 60°C. 10 g of graphite having a D of 50 of 20 μm was added thereto and maintained for 10 hours while stirring to hydrophilize the surface of the graphite powder. Thereafter, the hydrophilized graphite powder was recovered, washed three times by stirring in 100 g of deionized water, and recovered.
회수된 흑연 입자를 탈이온수 100g에 염화제일주석(SnCl2·2H2O) 1.5g과 염산(35% 용액) 6ml을 녹인 수용액에 투입하고 30분 동안 교반하여 주석층을 형성하였다. 수용액의 온도 35℃로 유지하였다.The recovered graphite particles were added to an aqueous solution in which 1.5 g of stannous chloride (SnCl 2 2H 2 O) and 6 ml of hydrochloric acid (35% solution) were dissolved in 100 g of deionized water and stirred for 30 minutes to form a tin layer. The temperature of the aqueous solution was maintained at 35°C.
주석층이 형성된 흑연 입자를 필터링을 통해 회수한 후, 탈이온수 100g에 질산은(AgNO3) 0.15g을 용해한 질산은 용액에 투입하고 교반하였다. 이때 28% 농도의 암모니아수를 점적방식으로 투입하여 pH를 9.3으로 조절하였다.After recovering the graphite particles on which the tin layer was formed through filtering, they were added to a silver nitrate solution in which 0.15 g of silver nitrate (AgNO 3 ) was dissolved in 100 g of deionized water, and stirred. At this time, 28% concentration of ammonia water was added dropwise to adjust the pH to 9.3.
온도는 40℃로 유지하고 1시간 교반하여 산화은층을 형성하였다. 1시간 후 여과 회수하고 이후 탈이온수 200g에서 교반하여 3회 세정한 후 회수하였다. 산화은층이 형성된 분말을 일부 채취하여 X선 광전자 분광법(X-ray Photoelectron Spectroscopy, XPS)를 통한 표면분석을 실시하였다.The temperature was maintained at 40°C and stirred for 1 hour to form a silver oxide layer. After 1 hour, it was collected by filtration, and then washed three times by stirring in 200 g of deionized water, and then recovered. A portion of the powder having the silver oxide layer was collected and surface analysis was performed through X-ray Photoelectron Spectroscopy (XPS).
산화은층까지 형성된 분말을 회수하고, 무전해도금법을 이용하여 구리 코팅층을 형성하였다. 탈이온수 용액 300g에 착체로서 EDTA(Ethylene-diamine-tetraacetic acid) 40g, NaOH 30g 및 황산구리 20g으로 황산구리 착체 수용액을 제조하고 산화은층이 형성된 흑연 분말을 투입하여 교반하면서 환원제로 포름알데히드(formaldehyde) 용액을 점적하여 구리를 포함하는 코팅층을 형성하였다. The powder formed up to the silver oxide layer was recovered, and a copper coating layer was formed using an electroless plating method. An aqueous solution of copper sulfate complex was prepared with 40 g of EDTA (Ethylene-diamine-tetraacetic acid), 30 g of NaOH, and 20 g of copper sulfate as a complex in 300 g of deionized water solution, and graphite powder having a silver oxide layer was added to it. While stirring, a formaldehyde solution was used as a reducing agent. It was applied dropwise to form a coating layer containing copper.
구리 코팅층이 형성된 흑연 분말 위에 다시 니켈 코팅층을 형성하였는데, 이를 위해 탈이온수 300g에 염화니켈(NiCl2·6H2O) 20g, 소듐아세테이트(sodium acetate) 10g, 말레인산(Maleic acid) 5g, 환원제인 차아인산나트륨(sodium hypophosphate) 30g, 리드아세테이트(lead acetate) 3㎖를 투입하여 조성된 니켈 도금액에 구리 코팅층까지 형성된 분말을 투입하고 교반하면서 70∼90℃에서 2시간동안 유지하여 무전해도금하였다.A nickel coating layer was formed again on the graphite powder on which the copper coating layer was formed . The powder formed to the copper coating layer was added to the nickel plating solution prepared by adding 30 g of sodium hypophosphate and 3 ml of lead acetate, and maintained at 70 to 90 ° C. for 2 hours while stirring for electroless plating.
[실시예 2][Example 2]
구리 코팅층 형성까지는 실시예 1과 동일하게 진행하였고, 이후 은을 포함하는 코팅층을 무전해도금으로 형성하였다. 이를 위해 탈이온수 300g에 EDTA(Ethylene-diamine-tetraacetic acid) 2g, 28% 농도의 암모니아수 2.5ml, 질산은(AgNO3) 3g으로 은 코팅액을 제조한 후, 여기에 구리 코팅층까지 형성된 흑연 입자를 투입하고 교반하면서 탈이온수 50g에 글루코스(glucose) 10g과 수산화나트륨 2g을 녹인 환원 용액을 1시간 동안 점적하여 은을 포함하는 제 3 층을 형성하였다. The copper coating layer was formed in the same manner as in Example 1, and then a coating layer containing silver was formed by electroless plating. To this end, after preparing a silver coating solution with 300 g of deionized water, 2 g of EDTA (Ethylene-diamine-tetraacetic acid), 2.5 ml of 28% concentration ammonia water, and 3 g of silver nitrate (AgNO 3 ), graphite particles formed up to a copper coating layer were added, While stirring, a reducing solution in which 10 g of glucose and 2 g of sodium hydroxide were dissolved in 50 g of deionized water was added dropwise for 1 hour to form a third layer containing silver.
[실시예 3][Example 3]
실시예 1과 동일하게 흑연 입자 표면에 산화은을 포함하는 제 1 층까지 형성한 후, 알칼리 수용액에서 후처리를 실시하였다. 후처리를 위해 탈이온수 100g에 28% 농도의 암모니아수를 투입하고 60℃로 유지한 후 제 1 층까지 형성된 흑연 입자를 투입하여 교반하였다. 흑연 입자 투입 전 수용액의 pH는 10.1이었다.In the same manner as in Example 1, after forming the first layer containing silver oxide on the surface of the graphite particles, a post-treatment was performed in an aqueous alkali solution. For post-treatment, 28% ammonia water was added to 100 g of deionized water, maintained at 60° C., and graphite particles formed up to the first layer were added and stirred. The pH of the aqueous solution before adding the graphite particles was 10.1.
이후 구리를 포함하는 제 2 층과 니켈을 포함하는 제 3 층의 형성은 실시예 1과 동일하게 실시하였다. Thereafter, the second layer containing copper and the third layer containing nickel were formed in the same manner as in Example 1.
[비교예 1][Comparative Example 1]
실시예 1과 동일하게 친수화 처리와 주석층을 형성하였다. 이후 산화은층을형성하지 않고 바로 무전해도금을 실시하여 구리를 포함하는 제 2 층과 니켈을 포함하는 제 3 층을 차례로 형성하였다. 구리와 니켈의 무전해도금은 실시예 1과 동일하게 진행하였다.In the same manner as in Example 1, a hydrophilization treatment and a tin layer were formed. Thereafter, electroless plating was performed immediately without forming a silver oxide layer to sequentially form a second layer containing copper and a third layer containing nickel. Electroless plating of copper and nickel was performed in the same manner as in Example 1.
[비교예 2][Comparative Example 2]
실시예 1과 동일하게 흑연 입자 표면에 산화은을 포함하는 제 1 층까지 형성하였다. 이후 수용액에 아스코르빈산(Ascorbic acid)을 투입하여 표면에 있는 산화은 중 일부를 금속 은 상태로 만들고, 이후 무전해도금을 실시하여 구리를 포함하는 제 2 층과 니켈을 포함하는 제 3 층을 차례로 형성하였다. 구리와 니켈의 무전해도금은 실시예 1과 동일하게 진행하였다.In the same manner as in Example 1, a first layer containing silver oxide was formed on the surface of the graphite particles. Thereafter, ascorbic acid is added to the aqueous solution to make some of the silver oxide on the surface into a metallic silver state, and then electroless plating is performed to sequentially form a second layer containing copper and a third layer containing nickel. formed. Electroless plating of copper and nickel was performed in the same manner as in Example 1.
[비교예 3][Comparative Example 3]
실시예 1과 동일하게 구리 코팅층까지 형성하고 이후 공정을 실시하지 않았다.In the same manner as in Example 1, the copper coating layer was formed, and the subsequent process was not performed.
이렇게 만들어진 전도성 흑연 입자에 대해 제 1 층 형성 후 산화은과 금속은의 은 원소비율 분석, 은 원소 함량 니켈 함량 및 인 함량 분석 그리고 주사전자현미경(Scanning Electron Microscope, SEM)을 통한 코팅상태 관찰을 진행하였다. 은 원소비율은 제 1 층 형성 후 샘플을 채취하여 XPS를 통해 분석하였다. 은 원소 함량, 니켈 함량 및 인 함량은 유도결합플라즈마 질량분석기(Inductively Coupled Plasma Mass Spectrometer, ICP)를 통해 분석을 진행하였다.After the first layer was formed on the conductive graphite particles thus formed, the silver element ratio of silver oxide and metallic silver was analyzed, the silver element content, nickel content and phosphorus content were analyzed, and the coating state was observed through a scanning electron microscope (SEM). . The silver element ratio was analyzed by taking a sample after forming the first layer and using XPS. Elemental silver content, nickel content, and phosphorus content were analyzed through an inductively coupled plasma mass spectrometer (ICP).
신뢰성은 실시예 1~3과 비교예 1 및 2를 통해 만들어진 전도성 흑연 입자를 아크릴 바인더와 일정량 혼합하여 폴리이미드 필름 위에 도포하고 건조한 후 이를 용융된 납 위에서 30초 간 유지한 후 전도도를 측정하는 리플로우(reflow) 테스트를 통해 평가하였다. Reliability is measured by mixing a certain amount of conductive graphite particles made in Examples 1 to 3 and Comparative Examples 1 and 2 with an acrylic binder, applying them on a polyimide film, drying, maintaining the molten lead for 30 seconds, and then measuring the conductivity. It was evaluated through a reflow test.
그 결과는 아래 표 1에서 나타내었다. 여기서 Cu함량은 전체 전도성 흑연 입자를 기준으로 구리 원소가 차지하는 중량%를 나타낸 것이다.The results are shown in Table 1 below. Here, the Cu content represents the weight percent occupied by the copper element based on the total conductive graphite particles.
Agx+/Ag0 Ag x + /Ag 0 Cu함량(wt%)Cu content (wt%) 코팅상태coating condition 내식성(mΩ)Corrosion resistance (mΩ)
실시예 1Example 1 1.911.91 10.510.5 양호Good 3535
실시예 2Example 2 2.512.51 12.112.1 양호Good 1919
실시예 3Example 3 7.837.83 9.89.8 양호Good 4545
비교예 1Comparative Example 1 -- -- 코팅안됨not coated --
비교예 2Comparative Example 2 0.510.51 불량error 120120
비교예 3Comparative Example 3 1.851.85 1111 양호Good 측정안됨not measured
도 1에서는 실시예에 따른 전도성 흑연 입자의 주사전자현미경 사진을 나타낸다. 도 1(a)는 실시예 1, 도 1(b)는 실시예 2, 도 1(c)는 비교예 1, 도 1(d)는 비교예 2에 따른 샘플의 주사전자현미경 이미지이다. 1 shows a scanning electron micrograph of conductive graphite particles according to an example. 1(a) is Example 1, FIG. 1(b) is Example 2, FIG. 1(c) is Comparative Example 1, and FIG. 1(d) is a scanning electron microscope image of a sample according to Comparative Example 2.
실시예 1과 2에 따른 샘플은 모두 치밀한 코팅층이 형성된 것을 나타내는데, 산화은을 포함하는 제 1 층이 없는 비교예 1에서는 코팅층이 제대로 형성되지 못하였고, 제 1 층에서 금속 은의 함량이 높은 비교예 2에서는 코팅층이 치밀하지 못하고 결합이 강하지 않은 것을 볼 수 있다. Samples according to Examples 1 and 2 both show that a dense coating layer was formed. In Comparative Example 1 without a first layer containing silver oxide, the coating layer was not formed properly, and in Comparative Example 2 with a high content of metallic silver in the first layer , it can be seen that the coating layer is not dense and the bonding is not strong.
도 2는 실시예 3에 따른 샘플에서 제 1 층의 산화은과 금속은의 은 원소 비율을 측정한 결과이다. XPS결과로 환원된 상태의 은 비율과 산화 상태의 은 비율을 피크 비율을 통해 측정할 수 있게 된다. 실시예 3에서의 이들 몰 비율(Agx+/Ag0 )은 7.83이었다. 2 is a result of measuring the ratio of silver elements of silver oxide and metallic silver in the first layer in the sample according to Example 3. As a result of the XPS, it is possible to measure the silver ratio in the reduced state and the silver ratio in the oxidized state through the peak ratio. This molar ratio (Ag x+ /Ag 0 ) in Example 3 was 7.83.
한편 표 1에서 나타낸 바와 같이 내식성은 리플로우 테스트를 통해 평가하였는데, 실시예 1 내지 3에서는 리플로우 테스트 후에도 전도성 흑연 입자를 이용한 필름의 저항은 50 mΩ 이하로 양호하였으나, 코팅층 형성이 불안정한 비교예 2에서는 저항이 크게 증가하였고, 보호층인 제 3 층이 형성되지 않은 비교예 3의 샘플에서는 저항이 너무 높아 측정되지 않았다.On the other hand, as shown in Table 1, corrosion resistance was evaluated through a reflow test. In Examples 1 to 3, the resistance of the film using the conductive graphite particles was good at 50 mΩ or less even after the reflow test, but the coating layer formation was unstable Comparative Example 2 In the sample of Comparative Example 3 in which the resistance was greatly increased, and the third layer, which is a protective layer, was not formed, the resistance was too high and was not measured.

Claims (10)

  1. 탄소계 입자 표면에 형성되는 산화은을 포함하는 제 1 층과, A first layer containing silver oxide formed on the surface of the carbon-based particles;
    상기 제 1 층 위에 형성되면서 구리를 포함하는 제 2 층; 및a second layer formed on the first layer and containing copper; and
    상기 제 2 층 위에 형성되며 니켈 또는 은을 포함하는 제 3 층을 포함하는, 전도성 탄소계 입자.A conductive carbon-based particle comprising a third layer formed on the second layer and comprising nickel or silver.
  2. 제 1 항에 있어서,According to claim 1,
    상기 탄소계 입자는, 흑연, 그래핀 및 CNT로 이루어지는 군에서 선택되는 일종 이상인, 전도성 탄소계 입자.The carbon-based particles are at least one type selected from the group consisting of graphite, graphene, and CNT.
  3. 제 1 항에 있어서,According to claim 1,
    상기 제 1 층은 금속 은을 더 포함하고, 상기 금속 은에서 은 원소에 대한 상기 산화은에서 은 원소의 몰 비율(Agx+/Ag0 ( 0< x ≤3 ))이 1 ~ 20범위인, 전도성 탄소계 입자.The first layer further comprises metallic silver, and the molar ratio of the silver element in the silver oxide to the silver element in the metallic silver (Ag x + /Ag 0 ( 0 < x ≤ 3 )) is in the range of 1 to 20, conductivity carbonaceous particles.
  4. 제 1 항에 있어서,According to claim 1,
    상기 제 1 층은 주석을 더 포함하는, 전도성 탄소계 입자.Wherein the first layer further comprises tin, conductive carbon-based particles.
  5. 제 1 항에 있어서,According to claim 1,
    상기 제 1 층에 포함되는 은의 함량은, 상기 전도성 탄소계 입자 전체 중량의 10~1,000 ppm인, 전도성 탄소계 입자. The content of silver included in the first layer is 10 to 1,000 ppm of the total weight of the conductive carbon-based particles.
  6. 제 1 항에 있어서,According to claim 1,
    상기 제 3 층은 상기 니켈과 함께 인을 더 포함하는, 전도성 탄소계 입자.Wherein the third layer further comprises phosphorus together with the nickel, the conductive carbon-based particles.
  7. 제 6 항에 있어서, According to claim 6,
    상기 제 3 층은 0.1~13.0 중량%의 인을 포함하는, 전도성 탄소계 입자.Wherein the third layer contains 0.1 to 13.0% by weight of phosphorus.
  8. (a) 탄소계 입자의 표면을 친수화 시키는 친수화 단계;(a) a hydrophilization step of hydrophilizing the surface of the carbon-based particles;
    (b) 상기 표면이 친수화된 탄소계 입자에 산화은을 코팅하는 제 1 층 형성 단계;(b) forming a first layer of coating silver oxide on the carbon-based particles whose surfaces are hydrophilic;
    (c) 상기 제 1 층 위에 구리를 무전해 도금하는 제 2 층 형성단계; 및(c) forming a second layer of electrolessly plating copper on the first layer; and
    (d) 상기 제 2 층 위에 니켈 또는 은을 무전해 도금하는 제 3 층 형성단계를 포함하는, 전도성 탄소계 입자 제조 방법.(d) forming a third layer of electrolessly plating nickel or silver on the second layer;
  9. 제 8 항에 있어서, According to claim 8,
    상기 (a)단계와 (b)단계 사이에, 주석층을 형성하는 단계를 더 포함하는, 전도성 탄소계 입자 제조 방법.The method of manufacturing conductive carbon-based particles, further comprising forming a tin layer between steps (a) and (b).
  10. 제 8 항에 있어서, According to claim 8,
    상기 (b)단계 후 상기 (c)단계 전에, pH 8~14이고, 온도 20~80℃인 수용액에서 상기 제 1 층이 형성된 탄소계 입자를 교반하여 상기 산화은 양을 조절하는 후처리 단계를 더 포함하는, 전도성 탄소계 입자 제조 방법.After the step (b) and before the step (c), a post-treatment step of adjusting the amount of the silver oxide by stirring the carbon-based particles on which the first layer is formed in an aqueous solution having a pH of 8 to 14 and a temperature of 20 to 80 ° C. A method for producing conductive carbon-based particles comprising:
PCT/KR2021/013907 2021-10-08 2021-10-08 Conductive carbon-based particles having excellent corrosion resistance WO2023058797A1 (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20050041318A (en) * 2003-10-30 2005-05-04 제일모직주식회사 Method of preparing multi-surface modified electroconductive particle
JP2010282832A (en) * 2009-06-04 2010-12-16 Hitachi Metals Ltd Bonding material, its manufacturing method, and mounting method using the same
KR20140133483A (en) * 2013-05-10 2014-11-19 주식회사 엘지화학 Copper containing particle and method for preparing the same
KR101543971B1 (en) * 2014-10-07 2015-08-12 성균관대학교산학협력단 Method for preparing metal oxide nanoparticles/graphene composite using supercritical fluides and metal oxide nanoparticles/graphene composite prepared thereby
KR20200035633A (en) * 2018-09-27 2020-04-06 주식회사 씨앤씨머티리얼즈 Nickel-coated super-abrasive particles with excellent magnetic properties and wire saw using the same

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20050041318A (en) * 2003-10-30 2005-05-04 제일모직주식회사 Method of preparing multi-surface modified electroconductive particle
JP2010282832A (en) * 2009-06-04 2010-12-16 Hitachi Metals Ltd Bonding material, its manufacturing method, and mounting method using the same
KR20140133483A (en) * 2013-05-10 2014-11-19 주식회사 엘지화학 Copper containing particle and method for preparing the same
KR101543971B1 (en) * 2014-10-07 2015-08-12 성균관대학교산학협력단 Method for preparing metal oxide nanoparticles/graphene composite using supercritical fluides and metal oxide nanoparticles/graphene composite prepared thereby
KR20200035633A (en) * 2018-09-27 2020-04-06 주식회사 씨앤씨머티리얼즈 Nickel-coated super-abrasive particles with excellent magnetic properties and wire saw using the same

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