Satin nickel plating solution and plating method

Abstract

The object of the present invention is to provide a satin nickel plating solution and plating method that can stably form a plated film with uniform and good appearance over a long period of time. A satin nickel plating solution containing saccharin and / or a saccharin salt, at least one acidic polysaccharide, at least one neutral polysaccharide, and at least one surfactant, and a plating method using the plating solution. The surfactant preferably contains a nonionic surfactant, and more preferably contains an anionic surfactant.

Description

[Technical Field]

[0001] The present invention relates to a satin nickel plating solution and a plating method. [Background technology]

[0002] Conventional methods for forming nickel plating films with a satin appearance include roughening the substrate by mechanical processes such as sandblasting or shot blasting, physically dispersing non-conductive fine particles in a nickel plating bath to form a co-deposit (composite method), and adding a surfactant, such as a quaternary ammonium salt and an organic anion substance, to the nickel plating bath to form an emulsion that inhibits electrolytic film deposition and thus achieves a satin appearance (emulsion method).

[0003] However, blasting is extremely expensive and is not suitable for current plating processes. The composite method is expensive to build the equipment required to uniformly disperse the fine particles, and the resulting satin finish is prone to unevenness. For this reason, satin nickel plating using the emulsion method is now the mainstream.

[0004] As examples of prior art using conventional emulsion methods, for example, Patent Document 1 discloses a nickel or nickel / cobalt plating bath containing benzyldimethyltetradecylammonium chloride and an organic anion substance. Patent Document 2 discloses a nickel or nickel / cobalt plating bath containing a quaternary ammonium salt and a sulfosuccinate ester. Patent Document 3 discloses a nickel or nickel / cobalt plating bath containing a quaternary ammonium salt and a polyether compound. Patent Document 4 discloses a nickel plating solution containing a saccharinate salt, a primary amine compound, and a cationic surfactant. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 3-39495 [Patent Document 2] U.S. Patent No. 6,919,014B2 [Patent Document 3] Special Publication No. 2006-508238 [Patent Document 4] International Publication No. 2018 / 066398 Brochure Summary of the Invention [Problem to be solved by the invention]

[0006] The conventional emulsion method described above has the problem that the time during which the plating solution can be used is very short. For example, the prior art described in Patent Documents 1 to 4 claims that the plating solution can be used for a long period of time, but in reality, significant changes in the appearance of the plating film can be observed within a few hours after the plating solution is prepared. In addition, emulsion aggregates may float on the surface of the plating solution and adhere to the surface of the object to be plated, causing problems such as poor appearance. The prior art described in Patent Document 4 claims that it is easy to obtain a satin appearance stably over a long period of time, but even this technology may impair the long-term stability of the satin nickel plating solution. Therefore, there is a demand for a satin nickel plating solution that is more stable and can be used for a long period of time.

[0007] In order to solve the above-mentioned problems, an object of the present invention is to provide a satin nickel plating solution and a plating method that can stably form a plating film with uniform and good appearance over a long period of time. [Means for solving the problem]

[0008] As a result of intensive research conducted by the present inventors to solve the above-mentioned problems, they discovered that adding a specific compound to a nickel plating solution improves the stability of the plating solution, allowing it to be used for a long period of time and enabling the formation of a plating film that is uniform and has a good appearance, and thus completed the present invention.

[0009] That is, the present invention provides the following (1) to (10). (1) A satin nickel plating solution comprising saccharin and / or a saccharin salt, at least one acidic polysaccharide, at least one neutral polysaccharide, and at least one surfactant. (2) The satin nickel plating solution according to (1) above, wherein the acidic polysaccharide is one or more selected from the group consisting of carrageenan, pectin, gum arabic, xanthan gum, gellan gum, agar, tragacanth gum, alginic acid, arabic acid, and soybean polysaccharides. (3) The satin nickel plating solution according to (1) or (2) above, wherein the neutral polysaccharide is one or more selected from the group consisting of starch, dextrin, pullulan, guar gum, locust bean gum, tamarind seed gum, tara gum, and chitin. (4) The satin nickel plating solution according to any one of (1) to (3) above, wherein the surfactant comprises a nonionic surfactant. (5) The satin nickel plating solution according to (4) above, wherein the nonionic surfactant comprises one or more surfactants selected from the group consisting of polyethylene glycol, polypropylene glycol, polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyethylene oxide-polypropylene oxide triblock copolymer, and polyoxyethylene-polyoxypropylene alkyl ether. (6) The satin nickel plating solution according to any one of (1) to (5) above, wherein the concentration of the acidic polysaccharide is 0.001 to 10 g / L. (7) The satin nickel plating solution according to any one of (1) to (6) above, wherein the concentration of the neutral polysaccharide is 0.001 to 10 g / L. (8) The satin nickel plating solution according to any one of (1) to (7) above, wherein the concentration of the surfactant is 0.001 to 1 g / L. (9) The satin nickel plating solution according to (4) above or any one of (5) to (8) above based on the same composition, wherein the surfactant further comprises at least one anionic surfactant. (10) A plating method comprising treating an object to be plated with any one of the satin nickel plating solutions (1) to (9) above. [Effects of the Invention]

[0010] The satin nickel plating solution of the present invention is stable and can be used for a long period of time, and can form a plating film with a uniform and good appearance. Furthermore, the plating method of the present invention can stably form a nickel plating film with a good satin appearance over a long period of time. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below based on embodiments, but the present invention is not limited to these embodiments.

[0012] ≪1. Plating solution≫ The plating solution of this embodiment is a satin nickel plating solution characterized by containing saccharin and / or a saccharin salt, at least one acidic polysaccharide, at least one neutral polysaccharide, and at least one surfactant. This can be obtained, for example, by adding an acidic polysaccharide and a neutral polysaccharide to a conventionally known nickel plating solution along with saccharin and / or its salt and a surfactant. The following description will mainly focus on a satin nickel plating solution based on a general-purpose nickel electroplating solution, which is a representative embodiment of the present invention.

[0013] <Nickel plating solution> In this embodiment, there are no particular limitations on the nickel plating solution that serves as the base, and any solution containing at least one nickel ion source can be used. For example, a conventionally known electrolytic nickel plating solution (electrolytic nickel plating solution) is also suitable as the base in this embodiment. Representative examples include known electrolytic nickel plating baths such as a nickel sulfate-based Watts bath and a nickel sulfamate bath, each having the following composition. Note that while the plating solution in the plating tank may sometimes be referred to as the "plating bath" to distinguish it from the "plating solution," in this embodiment, the two are considered to be the same, and the two terms will be used interchangeably in accordance with descriptions in various documents and common usage.

[0014] [Example of a typical composition of a nickel sulfate-based Watts bath] Nickel sulfate hexahydrate: 240-500g / L Nickel chloride hexahydrate: 20-100g / L Boric acid: 20-60g / L

[0015] [Example of a typical composition of a nickel sulfamate-based bath] Nickel sulfamate: 280-650g / L Nickel chloride hexahydrate: 0-40g / L Boric acid: 20-60g / L

[0016] The base electrolytic nickel plating solution is not limited to the above. For example, in the nickel-based bath, nickel chloride may be replaced with nickel bromide or the like. Furthermore, a metal ion source other than nickel may be contained. For example, a nickel alloy plating solution containing an ion source of cobalt, chromium, molybdenum, tungsten, or the like may also be used.

[0017] <Saccharin and saccharin salts> The plating solution of this embodiment contains saccharin and / or saccharin salts (hereinafter, chemical species including both of these may be referred to as "saccharin (salt)"). The inclusion of saccharin (salt) provides a good satin appearance.

[0018] There is no particular limitation on the type of saccharin salt, and various commonly used salts such as sodium salt, potassium salt, ammonium salt, etc. These saccharin salts and even saccharin can be used in combination of two or more types.

[0019] Preferably, a saccharin salt, particularly a sodium salt and / or a potassium salt, is used. The use of these saccharin salts facilitates obtaining a better satin appearance. Note that the saccharin or saccharin salt added to the plating solution may be converted to a saccharin salt or saccharin, respectively, depending on the pH of the plating bath, and this embodiment also encompasses plating solutions containing such converted forms of saccharin and / or saccharin salt.

[0020] The content of saccharin (salt) is not particularly limited, but is, for example, 0.001 to 20 g / L, preferably 0.05 g / L to 10 g / L. If the content of saccharin (salt) is within this range, the plating solution can be made more stable and usable for a long period of time.

[0021] <Acidic polysaccharide> The plating solution of this embodiment also contains at least one acidic polysaccharide. The inclusion of an acidic polysaccharide stabilizes the emulsion formed in the plating bath, making it possible to stably obtain a satin-like appearance over a long period of time. It also facilitates the production of a plating film with a uniform, good appearance without unevenness. The acidic polysaccharide is a polysaccharide that exhibits acidity when dissolved in water, for example, a polysaccharide that contains, as a constituent sugar, a monosaccharide having a carboxyl group in its backbone.

[0022] The acidic polysaccharides are not particularly limited, but examples thereof include carrageenan, pectin, gum arabic, xanthan gum, gellan gum, agar, tragacanth gum, alginic acid, arabic acid, soybean polysaccharides, etc., and preferably gum arabic and xanthan gum. These acidic polysaccharides may be used alone or in combination of two or more.

[0023] The content of the acidic polysaccharide is not particularly limited, but is, for example, 0.001 to 10 g / L, preferably 0.01 g / L to 1 g / L. If the content of the acidic polysaccharide (concentration in the plating solution) is within this range, the plating solution can be made more stable and usable for a long period of time.

[0024] <Neutral polysaccharide> The plating solution of this embodiment further contains at least one neutral polysaccharide. The inclusion of the neutral polysaccharide facilitates obtaining a uniform satin appearance over a wide range of current densities. The neutral polysaccharide is a polysaccharide that exhibits neutrality when dissolved in water or the like, such as a polysaccharide formed by dehydration polymerization of neutral sugars such as D-glucose, D-galactose, and D-mannose.

[0025] The neutral polysaccharides are not particularly limited, but examples thereof include starch, dextrin, pullulan, guar gum, locust bean gum, tamarind seed gum, tara gum, chitin, etc., and are preferably starch and dextrin. These neutral polysaccharides may be used singly or in combination of two or more.

[0026] The content of the neutral polysaccharide is not particularly limited, but is, for example, 0.001 to 10 g / L, preferably 0.01 to 1 g / L. If the content (concentration in the plating solution) of the neutral polysaccharide is within this range, it becomes easier to obtain a more uniform satin appearance over a wider current density range.

[0027] <Surfactant> The plating solution of this embodiment also contains at least one surfactant. The inclusion of a surfactant forms an emulsion, enabling a satin nickel plating solution to be obtained. There are no particular limitations on the type of surfactant, and various known surfactants, such as anionic, cationic, amphoteric, and nonionic surfactants, can be used. From the perspective of obtaining a good satin appearance, cationic, amphoteric, or nonionic surfactants are preferred, with amphoteric or nonionic surfactants being particularly preferred, and nonionic surfactants being particularly preferred. Multiple types of surfactants may be used in combination.

[0028] The content of the surfactant is not particularly limited, but is, for example, 0.001 to 1 g / L, preferably 0.001 to 0.1 g / L. If the content of the surfactant (concentration in the plating solution) is within this range, the plating solution can be made more stable and usable for a long period of time.

[0029] [Nonionic surfactant] It is particularly preferable that the surfactant contains a nonionic surfactant, which makes it easier to control the color tone of the satin appearance.

[0030] The nonionic surfactant is not particularly limited, but examples thereof include polyethylene glycol, polypropylene glycol, polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyethylene oxide-polypropylene oxide triblock copolymer, polyoxyethylene-polyoxypropylene alkyl ether, etc., with polyethylene glycol and polyethylene oxide-polypropylene oxide triblock copolymer being preferred. These nonionic surfactants may be used alone or in combination of two or more. Using two or more nonionic surfactants in combination may make the plating solution more stable and usable for a long period of time.

[0031] The content of the nonionic surfactant is not particularly limited, but is, for example, 0.001 to 1 g / L, and preferably 0.001 to 0.1 g / L. If the content of the nonionic surfactant is within this range, a better satin appearance can be obtained.

[0032] [Anionic surfactants] The plating solution of this embodiment preferably contains an anionic surfactant. The inclusion of an anionic surfactant makes it easier to suppress appearance defects such as pits. In particular, it is preferable to use a nonionic surfactant and an anionic surfactant in combination.

[0033] The anionic surfactant is not particularly limited, but examples thereof include sulfosuccinate esters represented by the following general formula (1). [ka] In the formula, R1 and R2 each independently represent hydrogen, an alkali metal ion, an alkaline earth metal ion, an ammonium ion, or a group having carbon atoms of C1 to C6. 18 Straight or branched chain alkyl, carbon number C1 to C 18 A is a chemical species selected from the group consisting of straight or branched chain alkenyl, and cyclic alkyl chains, and A is a chemical species selected from the group consisting of hydrogen, alkali metal ions, and alkaline earth metal ions.

[0034] More specific examples of sulfosuccinates include sodium di(1,3-dimethylbutyl)sulfosuccinate, sodium diisooctyl sulfosuccinate, sodium dihexyl sulfosuccinate, sodium diisopropyl sulfosuccinate, and sodium dibutyl sulfosuccinate, with sodium di(1,3-dimethylbutyl)sulfosuccinate and sodium dihexyl sulfosuccinate being preferred. These sulfosuccinates may be used singly or in combination of two or more.

[0035] The content of the anionic surfactant is not particularly limited, but is, for example, 0.001 to 0.5 g / L, and preferably 0.01 to 0.1 g / L. When the content of the anionic surfactant is within this range, it becomes easier to further suppress appearance defects such as pits.

[0036] <Preparation of plating solution> The plating solution of this embodiment can be prepared from the above-described components using a conventional method, and the details can be determined appropriately taking into consideration the composition and amount of each component. For example, the plating solution can be prepared by adding the above-described components to the base nickel electroplating bath and stirring until an emulsion is formed. Specifically, the plating solution can be prepared by stirring for about 30 to 60 minutes at a temperature between room temperature and about 60°C using a stirrer or liquid circulation equipment. There are also no particular limitations on the order in which the components are mixed.

[0037] <Other ingredients> In addition to the above components, the plating solution of this embodiment may also contain known additives for plating solutions.

[0038] <Features of the plating solution according to this embodiment> According to the plating solution of this embodiment, the emulsion that produces a satin appearance can remain stable in the plating solution for a long period of time, allowing for continuous use for a long period of time compared to conventional emulsion methods. In conventional emulsion methods, the emulsion aggregates in a relatively short time, and emulsion aggregates may float on the surface of the plating bath, causing poor appearance. Therefore, to maintain the satin appearance, it is often necessary to purify the plating bath with activated carbon every few hours. On the other hand, the plating solution of this embodiment can avoid such purification work, which can contribute to improving productivity and reducing manufacturing costs.

[0039] Although the present invention is not limited by any particular theory, it is believed that the reason the plating solution of this embodiment is stable and usable for a long period of time is that the micellar structure and dispersion state in the emulsion are stabilized by the coexistence of various polysaccharides and surfactants. Emulsions are thermodynamically unstable systems and are prone to collapse due to factors such as differences in specific gravity between the internal and external phases. When acidic polysaccharides and neutral polysaccharides, which differ in polarity and water solubility, coexist in an emulsion, they are distributed in a balanced manner between the internal and external phases, maintaining equal specific gravities between the two phases. As a result, the emulsion may be less susceptible to collapse. Furthermore, polysaccharides can also exhibit micelle-forming properties, and therefore, in the presence of surfactants and saccharin (salt), multiple types of micelles with different physical properties may be formed in the emulsion. Therefore, even if the environment surrounding the plating solution changes, some of the micellar structure may avoid collapse, maintaining the dispersion state of the emulsion.

[0040] 2. Plating method The plating method according to this embodiment is characterized by treating an object to be plated with the above-described satin nickel plating solution. For example, the object to be plated can be electroplated (electrolytically plated) using the above-described plating solution to provide satin nickel plating.

[0041] <Item to be plated> The types of substrates that can be plated with satin nickel plating are not particularly limited, as long as they are made of materials that can generally be nickel plated, and their shapes are also not particularly limited. For example, various metal materials and conductive ceramic materials are of course possible, but non-conductive ceramics, glass, carbon materials, resins, rubber, wood, and other non-conductors that have been made conductive by, for example, electroless plating or metal vapor deposition can also be used. Specific substrates include various decorative plating parts such as automobile front grilles, emblems and interior parts, and buttons for mobile phones.

[0042] Before electroplating, the substrate may be subjected to pretreatments such as alkaline degreasing, acid activation, and etching. For example, a metal substrate may be subjected to alkaline degreasing and acid activation treatments before electroplating. Furthermore, chemical nickel plating including catalyst addition or catalytic activity can be used as a treatment for making a non-conductor conductive, and treatments such as sputtering can also be used. For example, a substrate such as a resin can be subjected to etching, catalyst addition, and catalytic activation treatments, and then chemical nickel plating can be applied before electroplating.

[0043] The type of resin used as the substrate is not particularly limited. Examples include, but are not limited to, ABS (acrylonitrile-butadiene-styrene resin), PC (polycarbonate), PC-containing ABS, SBS (styrene-butadiene-styrene copolymer), acrylic resin, polyolefin resin such as polypropylene or polyethylene, polyphenylene oxide, polyphenylene sulfide, polyacetal, polyamide, polyimide, polyester, polyvinyl acetate, polyurethane, epoxy resin, phenolic resin, and even CFRP (carbon fiber reinforced plastic) and CNF (cellulose nanofiber)-containing resin. Among these, ABS resin-based substrates are preferred because they are easy to plate and form a copper or copper alloy surface layer.

[0044] <Plating conditions> The electroplating conditions are not particularly limited, and ordinary nickel plating conditions can be used. For example, the pH of the plating bath can be set within the range of 3 to 6, preferably within the range of 3.8 to 4.6. The bath temperature is, for example, within the range of 40 to 60°C, more preferably within the range of 45 to 55°C. The cathode current density is, for example, 0.01 to 50 A / dm 2 Approximately, preferably 1 to 6 A / dm 2 and more preferably in the range of 2 to 5 A / dm 2 The electrolysis treatment time is, for example, 1 to 20 minutes, and preferably 8 to 15 minutes.

[0045] During electroplating, it is preferable to agitate the plating bath using a stirrer or air, or to agitate the object to be plated using a rocking device. There are no particular restrictions on the anode used in the plating process, and an electrode made of nickel or a nickel-based alloy may be used as the anode.

[0046] <Post-processing, etc.> After the satin nickel plating, finishing plating such as chrome plating, tin / cobalt plating, tin / nickel plating, or gold plating may be carried out according to a conventionally known method.

[0047] According to the plating method of this embodiment, a nickel plating film with a uniform and excellent satin appearance can be stably formed over a long period of time. The activated carbon treatment cycle of the plating solution can also be significantly extended, and the number of work steps and manufacturing costs can be reduced. [Example]

[0048] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0049] [Example 1] (Preparation of plating solution) A nickel plating base bath having the following composition was heated to 52°C, and while maintaining liquid circulation with a stirrer stirring (300 rpm), 11 mg / L of PEG20000 and 5.7 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA CORPORATION, ADEKA Pluronic (registered trademark) F-68) were added as nonionic surfactants to prepare a satin nickel plating bath (Bath 1 of the present invention).

[0050] <Nickel plating base bath> Nickel sulfate hexahydrate 450g / L Nickel chloride hexahydrate 40g / L Boric acid 45g / L Sodium saccharin 1g / L Gum arabic 25mg / L Soluble starch 25mg / L

[0051] (Electroplating Test) <Pretreatment> First, the Hull Cell brass plate was immersed in EBAPREP SK-144 (degreasing) manufactured by JCU Corporation at 55°C for 5 minutes, and then in EBAVATE V-345 (acid activity) manufactured by JCU Corporation at room temperature for 0.5 minutes.

[0052] <Electroplating (Hull Cell Test)> The pretreated Hull Cell brass plate was immersed in Inventive Bath 1, which had been prepared 0.5 hours earlier, under the following conditions to perform electroplating, thereby obtaining an evaluation sample (Sample No. 1) in which a satin nickel plating film was formed on the brass plate.

[0053] <Plating conditions> pH: 4.2 Bath temperature: 52℃ Bath volume: 300mL Anode: Nickel Total current: 2A Plating time: 10 minutes Agitation: Stirrer agitation (300 rpm)

[0054] Using the pretreated Hull Cell brass plate and Inventive Bath 1 that had been prepared for 4 hours, electroplating was performed by immersion under the plating conditions described above, to obtain an evaluation sample (Sample No. 2) in which a satin nickel plating film was formed on the brass plate.

[0055] (evaluation) <Visual evaluation> The appearance of the obtained evaluation sample was evaluated visually according to the following criteria. The results of the visual evaluation are shown in Table 1 below.

[0056] <Visual evaluation criteria> Uniform satin appearance across the entire surface: rated good The satin finish is noticeably rough or the satin finish is uneven: ×

[0057] <Brightness measurement> The evaluation samples (Sample No. 1 and Sample No. 2) were set in a spectrophotometer (CM-700d) manufactured by Konica Minolta, Inc. The current density of the evaluation samples was 3 A / dm 2 The lightness (L*) of each sample was measured under the following conditions. The difference in lightness between sample No. 1 and sample No. 2 was taken as ΔL*, and the rate of change in lightness was evaluated. Table 1 shows the lightness and ΔL*.

[0058] <Brightness measurement conditions> Light source: D65 Light receiving angle: 8° Measurement mode: SCE (specular reflection excluded)

[0059] <Gloss measurement> The evaluation samples (Sample No. 1 and Sample No. 2) were set in a Micro Trigloss gloss meter manufactured by BYK Gardner Co., Ltd. The current density of the evaluation samples was 3 A / dm 2 The gloss (60°GU) of each of the sections was measured under the following conditions. The difference in gloss between sample No. 1 and sample No. 2 was taken as Δ60°GU, and the rate of change in gloss was evaluated. Table 1 shows the gloss and Δ60°GU.

[0060] <Gloss measurement conditions> Light source: D65 Light receiving angle: 60°

[0061] [Example 2] The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (invention bath 2) was prepared and evaluation samples (samples No. 3 and No. 4) were made using 6.0 mg / L of PEG20000 and 1.0 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic P-103, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition was used as the nickel plating base bath. Table 1 shows the visual evaluation results, lightness, and gloss.

[0062] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 1g / L Gum arabic 100mg / L Pullulan 150mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0063] [Example 3] The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (invention bath 3) was prepared and evaluation samples (samples No. 5 and No. 6) were produced using 20.0 mg / L of PEG6000 and 2.0 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-88, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition as the nickel plating base bath. The results of visual evaluation, brightness, and gloss are shown in Table 1.

[0064] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 1g / L Xanthan gum 10mg / L Dextrin 150mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0065] [Example 4] The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (invention bath 4) was prepared and evaluation samples (samples No. 7 and No. 8) were produced using 20.0 mg / L of PEG20000 and 1.0 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-108, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition as the nickel plating base bath. Table 2 shows the visual evaluation results, brightness, and gloss.

[0066] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 1g / L Gellan gum 10mg / L Dextrin 150mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0067] [Comparative Example 1] The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (comparative bath 1) was prepared and evaluation samples (samples No. 9 and No. 10) were produced using 5.5 mg / L of PEG20000 and 2.8 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-68, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition as the nickel plating base bath. Table 2 shows the visual evaluation results, lightness, and gloss.

[0068] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 1g / L Xanthan gum 10mg / L Sodium dihexyl sulfosuccinate 15mg / L * Contains no neutral polysaccharides

[0069] Comparative Example 2 The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (comparative bath 2) was prepared and evaluation samples (samples No. 11 and No. 12) were produced using 5.5 mg / L of PEG20000 and 2.8 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-68, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition as the nickel plating base bath. Table 2 shows the visual evaluation results, brightness, and gloss.

[0070] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 1g / L Gellan gum 10mg / L Sodium dihexyl sulfosuccinate 15mg / L * Contains no neutral polysaccharides

[0071] Comparative Example 3 The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (comparative bath 3) was prepared and evaluation samples (samples No. 13 and No. 14) were produced using 11.0 mg / L of PEG20000 and 5.7 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-68, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition as the nickel plating base bath. Table 2 shows the visual evaluation results, brightness, and gloss.

[0072] <Nickel plating base bath> Nickel sulfate hexahydrate 450g / L Nickel chloride hexahydrate 40g / L Boric acid 45g / L Sodium saccharin 1g / L Soluble starch 112mg / L Sodium dihexyl sulfosuccinate 15mg / L * Contains no acidic polysaccharides

[0073] Comparative Example 4 The same procedures as in Example 1 were carried out, except that a satin nickel plating bath (comparative bath 4) was prepared and evaluation samples (samples No. 15 and No. 16) were produced using 5.5 mg / L of PEG20000 and 2.8 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-68, manufactured by ADEKA Corporation) as the nonionic surfactant and the following composition as the nickel plating base bath. Table 2 shows the visual evaluation results, brightness, and gloss.

[0074] <Nickel plating base bath> Nickel sulfate hexahydrate 450g / L Nickel chloride hexahydrate 40g / L Boric acid 45g / L Sodium saccharin 1g / L Pullulan 50mg / L Sodium dihexyl sulfosuccinate 15mg / L * Contains no acidic polysaccharides

[0075] Comparative Example 5 The same procedures as in Example 1 were carried out, except that evaluation samples (Sample No. 17 and Sample No. 18) were prepared using a satin nickel plating bath (Comparative Bath 5) corresponding to the prior art and having the following composition as the plating solution. Table 3 shows the visual evaluation results, lightness, and gloss.

[0076] <Conventional satin nickel plating bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 35g / L Boric acid 40g / L SATIN NICKEL EM1 (JCU Corporation) 10mL / L SATIN NICKEL EM2 (manufactured by JCU Co., Ltd.) 20mL / L SATIN NICKEL DS-A (manufactured by JCU Co., Ltd.) 0.1mL / L SATIN NICKEL DS-B (manufactured by JCU Co., Ltd.) 0.1mL / L

[0077] [Table 1]

[0078] [Table 2]

[0079] [Table 3]

[0080] Tables 1 to 3 reveal that the plating solutions of Examples 1 to 4 according to the present invention can form plating films with uniform and good appearances, while maintaining good appearance even 4 hours after preparation of the plating bath and suppressing color variations such as brightness and gloss. In particular, Examples 1 to 3, which used gum arabic or xanthan gum, showed little color variation. On the other hand, Comparative Examples 1 and 2, which did not contain a neutral polysaccharide, showed little color variation 4 hours after preparation of the plating bath, but the satin appearance was found to be non-uniform. Furthermore, Comparative Examples 3 and 4, which did not contain an acidic polysaccharide, showed poor plating film appearance, significant color variation 4 hours after preparation of the plating bath, and noticeable roughness of the satin tone. Similarly, Comparative Example 5, which represents the prior art, also showed significant color variation and noticeable roughness of the satin tone.

[0081] [Example 5] (Preparation of plating solution) A satin nickel plating bath (invention bath 5) was prepared using the same nonionic surfactant and nickel plating base bath as in Example 1, in the same manner as in Example 1.

[0082] (Electroplating Testing and Evaluation) The same procedures as in Example 1 were carried out, except that evaluation samples (Sample No. 19 and Sample No. 20, respectively) were prepared using Inventive Bath 5 prepared 0.5 hours after its preparation and Inventive Bath 5 prepared 24 hours after its preparation. Table 4 shows the visual evaluation results, brightness, and gloss.

[0083] [Example 6] The same procedures as in Example 5 were carried out, except that a satin nickel plating bath (Invention Bath 6) was prepared and evaluation samples (Sample Nos. 21 and 22) were produced using 9.0 mg / L of PEG20000 and 0.6 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic P-85, manufactured by ADEKA Corporation) as the nonionic surfactant and the nickel plating base bath had the following composition. Table 4 shows the visual evaluation results, lightness, and gloss.

[0084] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Gum arabic 100mg / L Soluble starch 25mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0085] [Example 7] The same procedures as in Example 5 were carried out, except that a satin nickel plating bath (Invention Bath 7) was prepared and evaluation samples (Sample No. 23 and Sample No. 24) were prepared using 5.5 mg / L of PEG20000 and 2.8 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic F-68, manufactured by ADEKA Corporation) as the nonionic surfactant and the nickel plating base bath had the following composition. Table 4 shows the visual evaluation results, lightness, and gloss.

[0086] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Gum arabic 100mg / L Dextrin 150mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0087] [Example 8] The same procedures as in Example 5 were carried out, except that a satin nickel plating bath (invention bath 8) was prepared and evaluation samples (samples No. 25 and No. 26) were prepared using only 30 mg / L of PEG20000 as the nonionic surfactant and the nickel plating base bath having the following composition. Table 5 shows the visual evaluation results, lightness, and gloss.

[0088] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Gum arabic 100mg / L Dextrin 25mg / L Sodium dihexyl sulfosuccinate 17mg / L

[0089] [Example 9] The same procedures as in Example 5 were carried out, except that a satin nickel plating bath (Invention Bath 9) was prepared and evaluation samples (Sample No. 27 and Sample No. 28) were prepared using 30.0 mg / L of polyethylene oxide-polypropylene oxide triblock copolymer (ADEKA Pluronic P-103, manufactured by ADEKA Corporation) as the nonionic surfactant and the nickel plating base bath had the following composition. Table 5 shows the visual evaluation results, lightness, and gloss.

[0090] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Gum arabic 100mg / L Dextrin 25mg / L Sodium dihexyl sulfosuccinate 17mg / L

[0091] [Example 10] Using the same nonionic surfactant as in Example 7 and a nickel plating base bath of the following composition, a satin nickel plating bath (invention bath 10) was prepared in the same manner as in Example 5, and evaluation samples (samples No. 29 and 30) were prepared and evaluated in the same manner as in Example 5. Table 6 shows the visual evaluation results, brightness and gloss.

[0092] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Gum arabic 50mg / L Dextrin 150mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0093] [Example 11] Using the same nonionic surfactant as in Example 7 and a nickel plating base bath of the following composition, a satin nickel plating bath (invention bath 11) was prepared in the same manner as in Example 5, and evaluation samples (samples No. 31 and 32) were prepared and evaluated in the same manner as in Example 5. Table 6 shows the visual evaluation results, lightness, and gloss.

[0094] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Arabic acid 100mg / L Dextrin 150mg / L Sodium dihexyl sulfosuccinate 15mg / L

[0095] Comparative Example 6 Using the same nonionic surfactant as in Example 7 and a nickel plating base bath of the following composition, a satin nickel plating bath (Comparative Bath 6) was prepared in the same manner as in Example 5, and evaluation samples (Sample No. 33 and Sample No. 34) were prepared and evaluated in the same manner as in Example 5. Table 6 shows the visual evaluation results, lightness, and gloss.

[0096] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Gum arabic 100mg / L Sodium dihexyl sulfosuccinate 15mg / L * Contains no neutral polysaccharides

[0097] Comparative Example 7 Using the same nonionic surfactant as in Example 7 and a nickel plating base bath of the following composition, a satin nickel plating bath (Comparative Bath 7) was prepared in the same manner as in Example 5, and evaluation samples (Sample No. 35 and Sample No. 36) were prepared and evaluated in the same manner as in Example 5. Table 7 shows the visual evaluation results, lightness, and gloss.

[0098] <Nickel plating base bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 40g / L Boric acid 40g / L Sodium saccharin 2g / L Dextrin 25mg / L Sodium dihexyl sulfosuccinate 15mg / L * Contains no acidic polysaccharides

[0099] [Comparative Example 8] The same procedures as in Example 5 were carried out to prepare evaluation samples (Sample No. 37 and Sample No. 38) using a satin nickel plating bath (Comparative Bath 8) corresponding to the prior art and having the following composition as the plating solution. Table 7 shows the visual evaluation results, lightness, and gloss.

[0100] <Conventional satin nickel plating bath> Nickel sulfate hexahydrate 470g / L Nickel chloride hexahydrate 35g / L Boric acid 40g / L SATIN NICKEL EM1 (JCU Corporation) 10mL / L SATIN NICKEL EM2 (manufactured by JCU Co., Ltd.) 20mL / L SATIN NICKEL DS-A (manufactured by JCU Co., Ltd.) 0.1mL / L SATIN NICKEL DS-B (manufactured by JCU Co., Ltd.) 0.1mL / L

[0101] [Table 4]

[0102] [Table 5]

[0103] [Table 6]

[0104] [Table 7]

[0105] Tables 4 to 7 reveal that the plating solutions of Examples 5 to 11 according to the present invention can form plating films with uniform and good appearances, and can suppress color variation while maintaining a good appearance even 24 hours after preparation of the plating bath. In particular, Examples 6 to 9 and 11, in which the acidic polysaccharide concentration was approximately 0.1 g / L or higher, showed small variations in brightness. On the other hand, Comparative Example 6, in which no neutral polysaccharide was added, showed little color variation 24 hours after preparation of the plating bath, but the satin appearance was uneven. Furthermore, Comparative Example 7, in which no acidic polysaccharide was added, showed significant color variation 24 hours after preparation of the plating bath, and furthermore, the satin appearance was rough immediately after preparation of the plating bath. Comparative Example 8, which is a conventional technology, showed even greater color variation than Comparative Example 5, with the satin appearance disappearing and resulting in a nearly glossy appearance.

[0106] As described above, it has been demonstrated that the satin nickel plating solution of the present invention is stable and can be used for a long period of time, and can form a plating film that is uniform and has a good appearance.

Claims

1. A satin nickel plating solution comprising saccharin and / or a saccharin salt, at least one acidic polysaccharide, at least one neutral polysaccharide, and at least one surfactant, wherein the surfactant includes a nonionic surfactant.

2. 2. The satin nickel plating solution according to claim 1, wherein the acidic polysaccharide is one or more selected from the group consisting of carrageenan, pectin, gum arabic, xanthan gum, gellan gum, agar, tragacanth gum, alginic acid, arabic acid, and soybean polysaccharides.

3. 2. The satin nickel plating solution according to claim 1, wherein the neutral polysaccharide is one or more selected from the group consisting of starch, dextrin, pullulan, guar gum, locust bean gum, tamarind seed gum, tara gum, and chitin.

4. 4. The satin nickel plating solution according to claim 1, wherein the nonionic surfactant comprises one or more surfactants selected from the group consisting of polyethylene glycol, polypropylene glycol, polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyethylene oxide-polypropylene oxide triblock copolymer, and polyoxyethylene-polyoxypropylene alkyl ether.

5. 4. The satin nickel plating solution according to claim 1, wherein the concentration of the acidic polysaccharide is 0.001 to 10 g / L.

6. 4. The satin nickel plating solution according to claim 1, wherein the concentration of the neutral polysaccharide is 0.001 to 10 g / L.

7. 4. The satin nickel plating solution according to claim 1, wherein the concentration of the surfactant is 0.001 to 1 g / L.

8. The satin nickel plating solution according to any one of claims 1 to 3, wherein the surfactant further comprises at least one anionic surfactant.

9. A plating method comprising treating an object to be plated with the satin nickel plating solution according to any one of claims 1 to 3.

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