Method for manufacturing a metal support

Abstract

The object of this invention is to provide a method for manufacturing a metal-supported material that enables metal loading onto a substrate without high-temperature treatment or palladium catalyst application, and is less prone to decomposition reactions in the treatment liquid. One method for manufacturing a metal-supported material comprises a process of atomizing at least two liquids—a first liquid containing a metal complex and a second liquid containing a reducing agent—and applying them separately to the substrate, thereby reducing the metal complex and causing the metal to precipitate on the substrate surface. In the application step, it is preferable to heat the substrate to a temperature in the range of 50–200°C, and it is also preferable to apply the first and second liquids alternately. The metal in the first liquid preferably comprises one or more selected from the group consisting of copper, silver, gold, nickel, palladium, platinum, iron, cobalt, zinc, and tin.

Description

Technical Field

[0001] This invention relates to a method for manufacturing metal-supported materials. Background Technology

[0002] Previously, chemical treatment methods, primarily electroless plating, were known as methods for loading metals onto the surfaces of non-conductive substrates such as polymers and ceramics. In conventional electroless plating processes, methods such as: temporarily contacting the substrate with a solution containing stannous ions, followed by contacting it with a solution containing palladium ions, and then performing metal plating (sensitizer-activator method); or attaching a catalyst such as colloidal palladium to the substrate, activating it with an acid, and then performing metal plating (catalyst-accelerator method) (see, for example, Patent Documents 1 and 2). Chemical treatment methods, primarily electroless plating, can plate surfaces simply by immersing the substrate, and are therefore widely used in various fields, with new treatment methods continuously being developed.

[0003] For example, Patent Document 3 discloses a processing method in which two liquids, an aqueous solution containing a silver compound and ammonia, and an aqueous solution containing a reducing agent, are simultaneously sprayed onto the surface of the object to be plated in a consistent manner. In the processing method described in Patent Document 3, since the object to be plated is not immersed in the plating solution, large-scale equipment such as an immersion tank is not required.

[0004] Similarly, as a film-forming method without impregnation of the workpiece, Patent Document 4 discloses a method in which atomizes a solution of the film-forming material and heat-treats it to form a film on a substrate. In this film-forming method, the film-forming speed is increased and productivity is improved by heat-treating the atom at a high temperature. This film-forming method is mainly applicable to the formation of oxide semiconductor thin films, but the document also describes the ability to perform heat treatment in a reducing gas atmosphere.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 63-93872

[0008] Patent Document 2: Japanese Patent Application Publication No. 2010-13708

[0009] Patent Document 3: Japanese Patent Application Publication No. 2006-16659

[0010] Patent Document 4: Japanese Patent Application Publication No. 2020-132905 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] In conventional electroless plating, the plating solution must be highly reactive to facilitate spontaneous metal deposition. In other words, the plating solution lacks chemical stability and may sometimes produce unexpected reactions such as spontaneous decomposition, leading to undesirable results. Furthermore, in conventional electroless plating, the addition of a palladium catalyst increases the cost and number of steps involved in this process, which is a significant challenge.

[0013] In the processing method described in Patent Document 3, since the processing solution containing the metal compound and the processing solution containing the reducing agent are separated into two liquids, adverse situations such as decomposition reactions of the plating solution rendering it unusable can be eliminated. However, in this method, since both liquids are simultaneously blown onto the same part of the substrate surface, decomposition reactions that do not contribute to loading metal onto the substrate surface cannot be completely avoided. Furthermore, the processing method described in Patent Document 3 is based on the conventional sensitizer-activator method, which essentially requires a palladium catalyst.

[0014] While the film-forming method described in Patent Document 4 does not require a palladium catalyst, it presents challenges as a method for forming metal films. It is not impossible to reduce the film-forming material to metal through heat treatment of the mist in a reducing gas atmosphere, but considering the high temperature of around 500°C, the applicable substrates are limited to heat-resistant substrates.

[0015] In order to solve the aforementioned problems, the present invention aims to provide a method for manufacturing metal-supported materials that enables the metal to be loaded onto a substrate without high-temperature treatment or palladium catalyst application, and is less likely to cause decomposition reactions in the treatment solution.

[0016] Methods for solving problems

[0017] The inventors conducted research to solve the aforementioned problems. Their findings revealed that by using a two-liquid process—a first liquid containing a metal complex and a second liquid containing a reducing agent—in a chemical plating process, and by atomizing these two liquids and applying them separately to the substrate to reduce the metal complex, metal-supported materials can be produced even without a palladium catalyst, the undesirable situation of decomposition of the processing liquid is eliminated, and high-temperature processing is not required, thus completing the present invention.

[0018] That is, the present invention provides the following (1) to (8).

[0019] (1) A method for manufacturing a metal support, comprising a method for manufacturing a metal support on the surface of a substrate. It includes an application process in which at least two liquids, a first liquid containing a metal complex and a second liquid containing a reducing agent, are atomized and applied separately to the substrate. The complex is reduced to cause the metal to precipitate on the surface.

[0020] (2) The metal support manufacturing method according to (1) above, wherein, in the imparting step, the substrate is heated to a temperature in the range of 50 to 200°C.

[0021] (3) The method for manufacturing a metal support according to (1) or (2) above, wherein the metal comprises one or more selected from the group consisting of copper, silver, gold, nickel, palladium, platinum, iron, cobalt, zinc and tin.

[0022] (4) A method for manufacturing a metal support according to any one of (1) to (3) above, wherein, in the imparting step, the first liquid and the second liquid are imparted alternately.

[0023] (5) The method for manufacturing a metal support according to any one of (1) to (4) above, wherein the average diameter of the mist of the first liquid and the mist of the second liquid is 0.1 to 1000 μm.

[0024] (6) A method for manufacturing a metal support according to any one of (1) to (5) above, wherein the substrate is porous.

[0025] (7) The method for manufacturing a metal support according to any one of (1) to (6) above, wherein, prior to the imparting step, there is no step of imparting a palladium-containing component.

[0026] (8) A method for manufacturing a metal load according to any one of (1) to (7) above, wherein, in the application step, the first liquid and the second liquid are respectively applied by means of their respective ultrasonic sprayers.

[0027] Invention Effects

[0028] According to the present invention, a method for manufacturing a metal support is provided, which enables easy and simple loading of metal onto the surface of a substrate. In the metal support manufacturing method of the present invention, the addition of a catalyst containing palladium or similar components, as is typically performed in chemical plating, is not required, high-temperature treatment is unnecessary, and the decomposition of the accompanying treatment solution is less likely to occur. Attached Figure Description

[0029] Figure 1 This is a schematic diagram illustrating one embodiment of a method for manufacturing a metal support. Detailed Implementation

[0030] The following describes specific embodiments of the present invention in detail, but the present invention is not limited to these embodiments.

[0031] 1. Manufacturing Method of Metal Supports

[0032] This embodiment is a method for manufacturing a metal support, which is a method for manufacturing a metal support on the surface of a substrate. It includes an application step of atomizing at least two liquids, a first liquid containing a metal complex and a second liquid containing a reducing agent, and applying them to the substrate respectively, so that the metal complex is reduced and the metal is deposited on the surface of the substrate.

[0033] The metal support manufacturing method according to this embodiment allows for easy and simple loading of metal onto the surface of a substrate, eliminating the need for high-temperature treatment or palladium catalyst application. It also reduces the likelihood of adverse effects such as decomposition of the accompanying treatment solution.

[0034] In this embodiment, dividing the processing liquid for metal loading into at least two liquids, and separately assigning a metal source liquid and a reducing agent liquid, is a crucial first condition. Because it is a two-liquid or multi-liquid type, unexpected reactions between the metal source (metal complex) and the reducing agent are less likely to occur, and adverse conditions such as decomposition of the processing liquid are less likely to occur. Alternatively, a combination of a metal complex and a reducing agent that would react in a single-liquid type can be used. For example, since highly reactive metal complexes and reducing agents can be used, the metal can be efficiently deposited on the substrate; from this perspective, a catalyst containing palladium is not required. Furthermore, this embodiment includes a method for manufacturing metal-supported materials that does not include a palladium-containing step prior to the assignment step.

[0035] Here, "each imparting a mist of the first liquid and a mist of the second liquid" means that the two liquids are disposed on the substrate surface without pre-mixing or atomizing them, and does not exclude the possibility of the first liquid and the second liquid being mixed or integrated on the substrate surface, for example. Furthermore, it does not mean that the metal complex and the reducing agent are separately fixed to the substrate surface, nor does it necessarily mean that they are imparted to separate portions of the substrate surface at intervals. Preferably, the two liquids are imparted alternately to establish a time difference.

[0036] The second important condition of this embodiment is that the treatment solution is atomized and applied to points on the substrate. With such an application method, the possibility of segregation of the metal complex and reducing agent, which are applied in two or more liquids, in their respective areas on the substrate surface is small, and the target metal is easily deposited uniformly on the substrate surface. Furthermore, the atomized treatment solution has the advantage of being easily and uniformly applied to, for example, recesses on the substrate surface. Moreover, if the treatment solution is applied using atomization, large-scale equipment such as immersion tanks is not required, and metal loading can be easily performed with a simple apparatus. In addition, compared to conventional methods that treat the workpiece in an immersion tank, it has the advantages of reducing the amount of treatment solution used and significantly reducing waste liquid containing metal ions. Therefore, especially when precious metals are deposited, it is also cost-effective compared to conventional processing methods. Hereinafter, the application process in this embodiment will be described first.

[0037] <Assignment Process>

[0038] In the application process of this embodiment, as described above, the processing liquid for loading the metal is atomized into a first liquid containing a metal complex and a second liquid containing a reducing agent, and each of these liquids is separately applied to the substrate. Here, "separately applied to the substrate" means that the operations of atomizing and applying the first liquid containing the metal complex to the substrate and the operations of atomizing and applying the second liquid containing the reducing agent to the substrate are performed separately.

[0039] The treatment liquid is not limited to the first liquid and the second liquid mentioned above, but may also include three or more liquids. For example, a third liquid or a fourth liquid may be used for any treatment, such as a liquid containing a metal complex different from the metal complex in the first liquid, a liquid containing a reducing agent different from the reducing agent in the second liquid, and / or a particulate dispersion.

[0040] For ease of understanding, the following is based on Figure 1 One specific example of two types of assignment operations will be explained. Figure 1 In the metal loading fabrication apparatus 1 shown, a mist 31 of a first liquid 3 containing a metal complex and a mist 41 of a second liquid 4 containing a reducing agent are applied to the surface of a substrate 2 via nozzles 5 and 6, respectively.

[0041] To explain in more specific terms, for example... Figure 1As shown, while the substrate 2 is rotated on the substrate holding member 7, mist 31 and mist 41 are simultaneously blown onto their respective portions. Because the substrate 2 rotates, the first liquid 3 and the second liquid 4, initially applied to their respective portions, are ultimately applied to the entire surface of the substrate 2. Alternatively, mist 31 and mist 41 can be sprayed continuously or intermittently from nozzles 5 and 6, alternately applying the first liquid 3 and the second liquid 4 to the surface of the substrate 2 multiple times. Furthermore, the first liquid 3 and the second liquid 4 are contained in their respective tanks 8 and 9, and can be atomized, for example, by ultrasonic elements 81 and 91.

[0042] It should be noted that the metal load manufacturing method of this embodiment is not limited to the method described above. For example, it can also be applied to substrates with shapes other than circular plates. In addition, methods such as spraying or inkjet coating without ultrasonic components can also be used. Mist 31 and mist 41 can be applied at time intervals, and three or more nozzles can be prepared to apply three or more types of processing liquids.

[0043] [Reduction of Metal Complexes]

[0044] The metal complex applied to the surface of the substrate through the operations described above is reduced to metal by a reducing agent applied through other operations. This reduction operation can be performed as an additional step after the application of the first liquid, the second liquid, and any third liquid, but is preferably performed substantially simultaneously with the application step. In the metal-supported material manufacturing method of this embodiment, the processing liquid used is divided into at least a first liquid and a second liquid, thus eliminating the risk of unexpected reactions during storage. Highly reactive substances can be used as the metal complex and the reducing agent. Furthermore, highly concentrated liquids can be used as the first and second liquids. Therefore, the reduction reaction of the metal complex can begin immediately after the first and second liquids are applied to the surface of the substrate.

[0045] (Heat treatment)

[0046] The reduction reaction of metal complexes can be carried out, for example, at room temperature, but heating is preferred to promote the reaction. Heating can be performed, for example, by heating the mist, and preferably by heating the substrate to be treated. Heating the substrate side promotes the precipitation of the metal, that is, the reaction on the substrate surface where the reduction of the metal complex should occur. Therefore, the treatment solution applied hardly causes side reactions and can be used specifically for metal precipitation. In addition, if the substrate is heated, spray heating is not required, and thus it is possible to prevent or suppress undesirable side reactions such as poor mist adhesion caused by solvent evaporation and changes in mist diameter.

[0047] There are no particular limitations on the heating conditions; the desired conditions can be selected based on the metal complex and reducing agent used, as well as the structure of the apparatus. It is preferable to heat the substrate to a temperature in the range of 50–200°C. Temperatures above 50°C can sufficiently promote the reduction reaction of the metal complex. Furthermore, if the heating temperature is below 200°C, undesirable conditions such as mist adhesion caused by solvent evaporation and unexpected side reactions are less likely to occur. The heating temperature of the substrate is more preferably 60–120°C, and particularly preferably around 70–110°C.

[0048] (Specific examples of processes and heat treatments)

[0049] The manufacturing method of this embodiment, which includes heat treatment, is again based on... Figure 1 The illustrated embodiment will be described in detail, for example, by heating the substrate 2 using the heating substrate holding member 7. If, in this state, the substrate 2 is rotated while mist 31 of the first liquid 3 and mist 41 of the second liquid 4 are applied to its surface, the mist 31 and mist 41 dry on the substrate surface, and the reduction reaction of the metal complex begins, resulting in metal precipitation. In this way, the reduction of the metal complex can be carried out substantially in one step while the first and second liquids are applied.

[0050] exist Figure 1 In the illustrated embodiment, the mist 31 of the first liquid 3 and the mist 41 of the second liquid 4 can be continuously or intermittently supplied. Therefore, for example, the operation of supplying the first liquid, supplying the second liquid, reducing the metal complex, supplying the first liquid, supplying the second liquid, and reducing the metal complex can be repeatedly performed to increase the thickness of the metal precipitate, such as the plating layer. Furthermore, a third nozzle can be installed on the metal load manufacturing apparatus to repeatedly perform the operation of supplying the first liquid containing the metal complex, supplying the second liquid, reducing the metal complex, supplying the liquid containing other metal complexes, supplying the second liquid, and reducing the other metal complexes, etc., to perform multilayer plating and alloy precipitation.

[0051] It should be noted that in this embodiment, the order in which the first liquid and the second liquid are applied to the substrate is not particularly limited, as long as they are each atomized and applied separately. It is preferable to apply the first liquid before the second liquid. Especially when the reactivity of the metal complex or reducing agent is high, applying the first liquid to the substrate first can prevent or suppress unexpected metal precipitation on areas other than the substrate surface. Furthermore, when applying the first and second liquids multiple times, it is preferable to alternate between them. These aspects also apply to situations where heat treatment is performed in a process different from the application step.

[0052] Furthermore, this embodiment includes a method for manufacturing a metal load in which a first liquid and a second liquid are alternately applied during the application process. For example, in Figure 1 In the metal support manufacturing apparatus shown, the mist 31 of the first liquid 3 and the mist 41 of the second liquid are respectively applied to one side of the surface of the substrate 2. Therefore, by rotating the substrate 2, the first liquid 3 and the second liquid 4 can be alternately applied to the substrate surface. Here, by heating the substrate 2, the above-described application of the first liquid 3-application of the second liquid 4-reduction reaction can be continuously and repeatedly performed.

[0053] Here, the particle size of the mist 31 of the first liquid 3 and the mist 41 of the second liquid are not particularly limited, and can be set to the desired particle size according to the type and concentration of the metal complex and reducing agent used, as well as the heating temperature of the substrate. It is preferable that the average diameter of the mist of the first liquid and the mist of the second liquid is 0.1 to 1000 μm, especially 1 to 500 μm. With such a diameter of mist, it is less likely to cause problems such as drying before contact with the surface of the substrate 2 or uneven application of the treatment liquid.

[0054] The aforementioned average diameter of the mist can be formed, for example, using an ultrasonic atomizer. Here, by changing the frequency of the ultrasonic transducer, the particle size of the generated mist can be varied. In a preferred embodiment, during the application process, the first liquid and the second liquid are applied using their respective ultrasonic atomizers. Figure 1 As shown, ultrasonic elements 81 and 91 can also be attached to the storage tanks 8 and 9 of the first liquid 3 and the second liquid 4. It should be noted that the frequency of the ultrasonic waves in the sprayer is not particularly limited, but is preferably 0.2 to 3.0 MHz, and particularly preferably around 1.0 to 3.0 MHz.

[0055] Alternatively, fog can also be formed by spraying, inkjet printing, or spraying from a nozzle atomizer, as described above. For example, a nozzle atomizer can be described as having... Figure 1 The device shown uses the same tank and nozzle, but instead of an ultrasonic element, it includes a pressurizing mechanism, and further includes a slit and a porous material at the nozzle tip. In this device, if the first and second liquids in the tank are pressurized, a mist of the first and second liquids can be ejected from the nozzle tip. It should be noted that in this case, the mist of the first and second liquids is formed at the nozzle tip, and... Figure 1 The two liquids are different and are not generated in the tank. The pressurization of the first and second liquids can be achieved, for example, by introducing inert gases such as nitrogen or reducing gases such as hydrogen into each tank.

[0056] As described above, the metal support manufacturing method of this embodiment allows for easy and simple loading of metal onto the surface of various substrates at relatively low temperatures. For example, the metal support manufacturing method of this embodiment does not require large-scale equipment such as immersion tanks, making it suitable for multi-variety, small-batch production and test production. Since high-temperature treatment is also unnecessary, the corresponding power consumption can be cut off. Hereinafter, the substrate to which the metal support manufacturing method of this embodiment is applied, as well as the first and second liquids used in the manufacturing method of this embodiment, will be described.

[0057] [Substrate]

[0058] As described above, the metal support manufacturing method of this embodiment does not require high-temperature processing, and therefore can be applied to various substrates. The material is not particularly limited; for example, it can be various insulating materials such as ceramics, glass, resin, rubber, and wood, as well as semiconductors and conductors. The shape of the substrate is also not particularly limited and is not restricted to any particular material. Figure 1 The substrate, as shown, can be a circular plate, a flat plate, or even have an uneven or three-dimensional shape. Its surface condition is not particularly limited; substrates with smooth surfaces, substrates with fine unevenness, and porous materials, among other desired shapes, can be used.

[0059] (Porous substrate)

[0060] The method for manufacturing metal supports according to this embodiment is particularly useful for porous substrates. If the substrate is porous, the mist imparted permeates into the substrate, thus facilitating the manufacture of metal supports in which the precipitated metal is firmly supported on the substrate.

[0061] [First Liquid]

[0062] The first liquid applied to the aforementioned substrate is a liquid containing a metal source, which is contained in the form of a metal complex. For example, if the metal commonly used in plating exists in the solution as a salt such as a chloride or sulfate, it may sometimes change into an oxide or hydroxide and precipitate due to pH changes, thus sometimes preventing the target metal from precipitating on the substrate. If there are pH-related limitations to the solution, the components that can be contained in the second liquid (described later) combined with the first liquid are also limited. On the other hand, by using a liquid containing a metal source in the form of a complex as the first liquid, not only the metal source but also various substances can be used as the reducing agent, resulting in a more reactive processing solution. In addition, reducing agents often function in an alkaline atmosphere, so using a first liquid containing a metal complex can also improve the reduction efficiency, i.e., the metal precipitation efficiency, while preventing precipitation.

[0063] (Metal complex)

[0064] The first liquid can contain metal complexes as long as they contain a metal supported on the substrate; there are no particular restrictions on the type. Here, "metal complex" refers to a group with multiple ligands bonded to metal atoms or metal ions, including not only transition metal ammonia complexes and acetylacetone complexes, but also a wide range of other metal complexes such as copper acetate (Cu2(CH3COO)4·2H2O) and stannate anions ([Sn(OH)6)). 2- Compounds such as )

[0065] The metal complex is preferably a complex containing one or more metals selected from the group consisting of transition metals such as copper, silver, gold, nickel, palladium, platinum, iron, cobalt, and zinc, as well as tin. These metals can impart various functions to a substrate as a coating, and when precipitated in the form of particles, they readily exhibit functions such as those of a catalyst. Among these, complexes containing one or more metals selected from the group consisting of copper, gold, nickel, palladium, platinum, iron, cobalt, zinc, and tin are preferred. It should be noted that complexes containing these metals may also contain other metals, such as alkali metals.

[0066] The ligands in the metal complex are not particularly limited and can be selected from various Lewis bases. Preferably, metal complexes have one or more ligands selected from ammonia, amines, imines, urea compounds, diketone anions, carboxylate anions, amino acids, thiosulfate anions, dithiosulfate compounds, cyano, isocyano, thiocyanate, nitro, nitrite, and halogen atoms. Metal complexes with such ligands have the advantage of facilitating the precipitation of metal and the adjustment of its rate. Ammonia, carboxylate anions, amino acids, thiosulfate anions, and halogen atoms are particularly preferred.

[0067] Examples of ligands for amine compounds include aliphatic monoamines such as trimethylamine and triethylamine, aliphatic diamines such as ethylenediamine, polydentate ligands such as triaminotripropylamine, and aromatic amines such as pyridine, bipyridine, and phenanthroline. Examples of ligands for imine compounds include Schiff bases such as porphyrins, phthalocyanines, and biguanides. Examples of urea compounds include urea, biuret, and hydantoin derivatives. Examples of carboxylate anions include formate anions, acetate anions, propionate anions, oxalate anions, citrate anions, phthalate anions, and gluconate anions. Examples of amino acids include EDTA, glycine, and histidine. Examples of dithiol compounds include maleic anhydride and 1,2-benzenediol. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. These chemical species are not limited to those exemplified herein, and various well-known chemical species may be used.

[0068] The first liquid can contain multiple metal complexes. Furthermore, the metal complexes can have multiple metals and / or ligands. For example, a first liquid containing multiple complexes with different metals, or a polynuclear complex, can be used to precipitate the alloy and load it onto a substrate. The ligands in the metal complexes of the first liquid act as complexing agents, thus allowing two or more metal ions to coexist and adjusting the precipitation rate of each metal. Therefore, two-liquid or multi-liquid processing solutions containing metal complexes as metal sources are suitable for alloy plating and loading of alloy powders.

[0069] The concentration of the metal complex in the first liquid is not particularly limited. For example, in molar conversion of metal atoms, it can be set to a concentration of 0.01 to 5 mol / L, especially 0.03 to 3 mol / L, especially 0.05 to 1 mol / L, but is not limited to such a concentration. In the metal-supported material manufacturing method of this embodiment, since there is little need to avoid unexpected reactions between the metal complex and the reducing agent, the processing liquid can contain the metal complex at a high concentration. Therefore, it is also possible to efficiently precipitate the metal on the substrate.

[0070] (solvent)

[0071] There are no particular restrictions on the solvent of the first liquid. Aqueous solvents are preferred, and water is particularly preferred, but any solvent capable of dissolving the metal complex can be used. For example, acetylacetone complexes can be dissolved in alcohol or carbonate solvents, or in ether solvents such as diphenyl ether, tetrahydrofuran, or dioxane. Multiple solvents can also be used in combination.

[0072] (additive)

[0073] In addition to metal complexes and solvents, the first liquid may also contain various additives such as pH adjusters, pH buffers, hydrogen production inhibitors, dispersants, dispersing aids, emulsifiers, surfactants, viscosity adjusters, gloss agents, inhibitors, antioxidants, conductive salts, wetting agents, and pigments.

[0074] [Second Liquid]

[0075] The second liquid is a liquid containing a reducing agent. As described above, in the metal support manufacturing method of this embodiment, since the second liquid containing the reducing agent and the first liquid containing the metal source are different liquids, it is possible to prevent unexpected reactions between the metal complex and the reducing agent as in conventional single-liquid electroless plating solutions. Therefore, a wide variety of reducing agents can be used.

[0076] (reducing agent)

[0077] There are no particular restrictions on the type of reducing agent; various known reducing agents can be used. Examples include aldehydes, formic acid and its salts, hydrazine compounds, aminoboranes, glyoxylic acid, ascorbic acid, hypophosphorous acid and their salts, sugars, alcohols, and boron hydride compounds, but these are not limited to these. Preferably, these reducing agents contain one or more compounds selected from aldehydes, formic acid, formate salts, hydrazine compounds, aminoboranes, glyoxylic acid (salts), ascorbic acid (salts), hypophosphorous acid (salts), sugars, alcohols, and NaBH4(SBH). These reducing agents have the advantage of facilitating the precipitation of metals and the adjustment of their rate.

[0078] Here, examples of aldehydes include formaldehyde and acetaldehyde; examples of hydrazine compounds include H2NNH2, its hydrochloride or sulfate; examples of aminoboranes include aminoborane, dimethylaminoborane, morpholineborane, etc.; examples of sugars include glucose, fructose, glyceraldehyde, lactose, arabinose, maltose, etc.; and examples of alcohols include methanol, ethanol, ethylene glycol, etc., but are not limited to these.

[0079] The concentration of the reducing agent in the second liquid is not particularly limited. For example, it can be set to a concentration of 0.01 to 10 mol / L, especially 0.1 to 5 mol / L, especially 0.5 to 3 mol / L, but is not limited to such a concentration. In the metal support manufacturing method of this embodiment, since there is little need to avoid unexpected reactions between the metal complex and the reducing agent, the processing liquid can contain a high concentration of reducing agent. Therefore, the precipitation of metal on the substrate can be carried out efficiently.

[0080] (solvent)

[0081] The solvent for the second liquid is not particularly limited and can be the same as the solvent for the first liquid. Preferably, the solvent for the second liquid is a solvent with the same or similar composition as the solvent for the first liquid. This is to prevent the precipitation of one component during the unreacted stage or midway through the reaction when the two liquids are mixed or come into contact during the application process.

[0082] (additive)

[0083] In addition to metal complexes and solvents, the second liquid may also contain various additives such as pH adjusters, pH buffers, hydrogen production inhibitors, dispersants, dispersing aids, emulsifiers, surfactants, viscosity adjusters, gloss agents, inhibitors, antioxidants, conductive salts, wetting agents, and pigments.

[0084] [Any processing liquid after the third liquid]

[0085] As described above, the metal-supported material manufacturing method of this embodiment may include the application of three or more liquids. That is, in addition to the first and second liquids, a third or fourth liquid, etc., for any processing, may be applied. There are no particular limitations on the processing liquids after the third liquid, and various known processing liquids such as particulate dispersions, gloss-enhancing treatment liquids, liquids of metal complexes different from the first liquid, liquids of reducing agents different from the second liquid, liquids containing surfactants, and liquids containing pH buffers can be used.

[0086] <Any processing procedure>

[0087] In addition to the application steps of the first liquid and the second liquid, the metal loading method of this embodiment may also include a pretreatment step and a posttreatment step. Furthermore, when using a substance with high stability, or in other words, low reactivity, as the metal complex and / or reducing agent, it is preferable to perform heat treatment as a heat reduction step different from the application step.

[0088] (Heating and reduction process)

[0089] The aforementioned heating reduction process can be performed, for example, by placing the substrate after the coating process of the first liquid and the second liquid into a heating furnace and maintaining it at a temperature of approximately 100–1000°C, particularly 200–800°C, for 5–300 minutes, particularly 10–180 minutes. It should be noted that such a heating reduction process can be performed under an inert gas atmosphere such as nitrogen, or a reducing gas atmosphere such as hydrogen.

[0090] (Pre-processing step)

[0091] Before the application of the first liquid and the second liquid, etc., the substrate can be subjected to pretreatment processes such as cleaning, degreasing, etching, and conditioning. It should be noted that the metal support manufacturing method of this embodiment does not require a catalyst containing palladium, but a pretreatment process for applying such a palladium-based catalyst can be added as desired.

[0092] (Post-processing steps)

[0093] Further post-processing steps can be performed on the metal-loaded substrate, including lamination of the metal plating layer based on electrolytic plating, chromate treatment, formation of an electrolytic chemical conversion treatment film, formation of an impregnation chemical conversion treatment film, coating of solder resist, rust prevention treatment, and planarization based on CMP. Alternatively, a component with palladium or the like loaded on its surface using the metal-loaded material manufacturing method of this embodiment can be used as a substrate for further chemical plating treatment.

[0094] 2. Applications of Metal Supports

[0095] The metal support manufacturing method of this embodiment, as described above, allows for the easy and simple manufacture of various metal supports, such as metal-plated parts, from various substrates. Since these metal supports possess a metal plating film or powdered metal precipitates on their surface, they can be used as various materials for various applications. For example, metal supports with a metal plating film can be used in electronic components, primarily industrial materials of various shapes, automotive parts, outboard motor parts, faucet fittings, building material parts, household appliance parts, and various substrates such as printed circuit boards and disk substrates. Metal supports with powdered metal precipitates are also useful as catalysts, adsorbents, etc.

[0096] Example

[0097] The present invention will be further described in detail below by way of examples, but the present invention is not limited thereto in any way described herein.

[0098] Example 1

[0099] Install the plate-shaped porous glass substrate (25mm×50mm, 1mmt) on Figure 1 The first liquid and the second liquid described below are atomized and applied to the surface of the substrate on the substrate holding member of the metal load manufacturing apparatus (made by Tokyo University of Science) as described herein.

[0100] • First liquid: A mixed aqueous solution of CuSO4·5H2O (0.13 mol / L) and NH3 (0.73 mol / L) (pH: 11.0)

[0101] • Second liquid: 0.33 mol / L aqueous solution of hydrazine sulfate (pH adjusted to 9.95 by adding sodium hydroxide).

[0102] (Conditions assigned to the process)

[0103] The application of both the first and second liquids is carried out under the following conditions.

[0104] • Substrate temperature: 90℃

[0105] • Substrate rotation speed: 20 rpm

[0106] • Fog generation source: Nozzle sprayer (capable of producing fog with a diameter of 10–1000 μm)

[0107] • Average mist output: 30 ml / min

[0108] • Spray gas flow rate: 8L / min (nitrogen)

[0109] • Coating time: 20 minutes

[0110] (Evaluation Method)

[0111] The precipitation state of the metal in the test sample was evaluated by visual observation using an optical microscope and X-ray diffraction on a water-washed and dried glass substrate. The evaluation results, along with the main components of the treatment solution, are shown in Table 1 below. In this embodiment, metal precipitates were observed on the glass substrate, and the precipitation of metallic copper was confirmed by measuring the diffraction pattern of copper using XRD.

[0112] Example 2

[0113] The following liquids were used as the first and second liquids, and the conditions of the imparting process were changed as described below. Otherwise, the same operation as in Example 1 was performed. The evaluation results are also shown in Table 1 below, and the precipitation of metallic copper was confirmed in the same manner as in Example 1.

[0114] • First liquid: A mixed aqueous solution of CuSO4·5H2O (0.4 mol / L) and NH3 (2.2 mol / L) (pH: 11.0)

[0115] • Second liquid: A 1.0 mol / L aqueous solution of hydrazine sulfate (with sodium hydroxide added to adjust the pH to 10.30)

[0116] (Conditions assigned to the process)

[0117] The first liquid application process and the second liquid application process are both carried out under the following conditions.

[0118] • Substrate temperature: 80℃

[0119] • Substrate rotation speed: 150 rpm

[0120] • Fog generation source: Ultrasonic sprayer (can produce fog with a diameter of 0.1 to 10 μm)

[0121] • Average mist output: 0.63 ml / min

[0122] • Spray gas flow rate: 10L / min (nitrogen)

[0123] • Coating time: 60 minutes

[0124] Example 3

[0125] The same operation as in Example 2 was performed using an alkali-free glass substrate of the same size as the substrate. The evaluation results are also shown in Table 1 below, and the precipitation of metallic copper was confirmed in the same manner as in Examples 1 and 2.

[0126] Comparative Example 1

[0127] After mixing the first and second liquids used in Examples 2 and 3, an attempt was made to apply the solution to the substrate. Immediately after mixing, the metal complex and reducing agent began to react, the treatment solution decomposed, and precipitation began. Therefore, it was impossible to apply the treatment solution to the substrate surface itself. According to this comparative example, the two-liquid treatment solutions used in Examples 2 and 3 have potentially high reactivity; however, even when the two liquids were separately atomized and applied to the substrate, metal could be stably precipitated.

[0128] Comparative Example 2

[0129] Without using a second liquid, the same procedure as in Example 2 was performed to attempt to deposit it onto the substrate. The results are also shown in Table 1, but no metallic copper was deposited.

[0130] Example 4

[0131] The following liquids were used as the first and second liquids, and the average spray rate was set to 0.74 ml / min. Otherwise, the same procedures as in Example 3 were performed. The deposition of metallic nickel was confirmed in the same manner as in Examples 1-3.

[0132] • First liquid: A mixed aqueous solution of NiSO4·6H2O (0.4 mol / L) and NH3 (5.0 mol / L) (pH: 12.04)

[0133] • Second liquid: A mixed aqueous solution of dimethylamine borane (DMAB) and NaBH4 (SBH) (1.0 mol / L + 0.26 mol / L, with the pH adjusted to 9.77 by adding sodium hydroxide).

[0134] Example 5

[0135] Porous alumina was used as the substrate, and the average mist output was set to 0.48 ml / min. Otherwise, the same procedures as in Example 4 were performed. As in Example 4, the precipitation of metallic nickel was confirmed.

[0136] Comparative Example 3

[0137] After mixing the first liquid used in Examples 4 and 5 with the second liquid described below, an attempt was made to apply the solution to the substrate. Although the second liquid was a dilute solution as described below, the metal complex and reducing agent began to react immediately after the two liquids were mixed, the treatment solution decomposed, and precipitation began to occur. Therefore, it was impossible to apply the treatment solution to the substrate surface itself.

[0138] • Second liquid: 0.01 mol / L aqueous solution of NaBH4(SBH)

[0139] Example 6

[0140] The following liquids were used as the first and second liquids, and the average spray rate of the mist was 0.44 ml / min, the coating time was 30 minutes, and the same operation as in Example 2 was performed. Gold precipitation was confirmed in the same manner as in Examples 1-3.

[0141] • First liquid: A mixed aqueous solution of gold sulfite (0.06 mol / L) and thiosulfate (0.4 mol / L) (pH: 10.99)

[0142] • Second liquid: 1.0 mol / L aqueous solution of L-ascorbic acid sodium (pH adjusted to 13.0 by adding sodium hydroxide)

[0143] Example 7

[0144] The same procedure as in Example 6 was performed using a polyimide film of the same size as the substrate. Gold precipitation was confirmed in the same manner as in Example 6.

[0145] The evaluation results from Examples 1-7 and Comparative Examples 1-3, along with the main components of the treatment liquid and the material of the substrate, are summarized in Tables 1 and 2 below. It is shown that by atomizing a first liquid containing a metal complex and a second liquid containing a reducing agent and separately applying them to the substrate, the metal complex is reduced, enabling the metal to be loaded onto the surface of the substrate without causing decomposition of the treatment liquid. According to this method of manufacturing metal-supported materials, it is evident that regardless of the type of substrate or the components in the treatment liquid, metal can be easily and conveniently loaded onto the surface of the substrate without the need for catalysts containing palladium or large-scale equipment, and manufacturing costs can also be reduced.

[0146] The test results are summarized in Tables 1 and 2 below. It should be noted that in the evaluation results in the tables, metal precipitation is indicated by "○", and no precipitation is indicated by "×". Additionally, cases where the treatment solution could not be applied to the substrate are indicated by "-".

[0147] [Table 1]

[0148] [Table 2]

[0149] Symbol Explanation

[0150] 1. Metal Load Manufacturing Apparatus

[0151] 2. Substrate

[0152] 3 First Liquid

[0153] 31 The first liquid mist

[0154] 4 Second Liquid

[0155] 41. Mist of the Second Liquid

[0156] 5 nozzles

[0157] 6 nozzles

[0158] 7. Substrate retaining components

[0159] 8 First liquid tank

[0160] 81 Ultrasonic Components

[0161] 9. Second liquid tank

[0162] 91 Ultrasonic Components

Claims

1. A method for manufacturing a metal support, comprising a method for manufacturing a metal support on the surface of a substrate, wherein a metal is loaded onto the surface of the substrate. It includes an application process in which at least two liquids, a first liquid containing a metal complex and a second liquid containing a reducing agent, are atomized and applied separately to the substrate. The complex is reduced to cause the metal to precipitate on the surface.

2. The method for manufacturing a metal support according to claim 1, wherein, In the imparting process, the substrate is heated to a temperature in the range of 50°C to 200°C.

3. The method for manufacturing a metal support according to claim 1 or 2, wherein, The metal comprises one or more selected from the group consisting of copper, silver, gold, nickel, palladium, platinum, iron, cobalt, zinc and tin.

4. The method for manufacturing a metal support according to claim 1 or 2, wherein, In the application process, the first liquid and the second liquid are applied alternately.

5. The method for manufacturing a metal support according to claim 1 or 2, wherein, The average diameter of the mist from the first liquid and the mist from the second liquid is 0.1 μm to 1000 μm.

6. The method for manufacturing a metal support according to claim 1 or 2, wherein, The substrate is porous.

7. The method for manufacturing a metal support according to claim 1 or 2, wherein, The process of applying palladium-containing components is not included before the application process.

8. The method for manufacturing a metal support according to claim 1 or 2, wherein, In the application process, the first liquid and the second liquid are applied using their respective ultrasonic sprayers.

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