WO2007007617A1

WO2007007617A1 - Surface treatment in presence of organic solvent

Info

Publication number: WO2007007617A1
Application number: PCT/JP2006/313420
Authority: WO
Inventors: Takabumi Nagai; Kazuhisa Fujii; Hideaki Asai
Original assignee: Daikin Industries, Ltd.
Priority date: 2005-07-08
Filing date: 2006-07-05
Publication date: 2007-01-18

Abstract

In an electrochemical surface treatment, reduction of a metal waste liquid and formation of a high-quality metal film, which exhibits good adhesion and has no pinhole, are easily realized. Specifically disclosed is a surface treatment method characterized by subjecting an object to a surface treatment in the presence of both an aqueous solution containing a metal salt and a hydrophobic solvent. In this connection, the surface treatment is selected from electrolytic plating, chemical plating, electroforming, anodizing, electrolytic polishing, electrolytic processing, electrophoretic coating, electrolytic refining and chemical conversion coating.

Description

Specification

Surface treatment in the presence of organic solvents

Technical field

[0001] The present invention relates to an electrochemical reaction. More specifically, the present invention relates to an electrochemical reaction efficiency technology and a surface treatment technology using the same by adding an aqueous metal salt solution and a hydrophobic solvent.

Background art

In electroplating (electrolytic plating), cracks and pinholes are generated on the plating film due to hydrogen generated by electrolysis of the plating solution. Various techniques have been developed to prevent this. Among them, as a promising method, a method of peeling bubbles by reducing the surface tension by using a surfactant has been studied. In particular, fluorosurfactants are considered to have higher functionality than other surfactants, and various compounds have been disclosed (Patent Documents 1 and 2).

[0003] However, it is difficult to produce a completely pinholeless metal thin film by these methods, and it has been avoided by applying a thick coating as much as the cost permits. Or a dry process such as a notch is used.

Patent Document 1: Patent No. 3334594

Patent Document 2: JP-A-64-25995

Disclosure of the invention

Problems to be solved by the invention

[0004] An object of the present invention is to provide a technique for reducing a metal waste liquid in an electrochemical surface treatment and easily realizing a high-quality metal film with good adhesion and no pinholes. Means for solving the problem

[0005] Solvents, polysiloxanes, and ionic liquids composed of perfluoroalkyl compounds are known to dissolve a large amount of gas in the solvent as compared to general hydrocarbon solvents. .

[0006] [Table 1] Oxygen solubility in various solvents

[0007] Table 1 shows the solubility of oxygen. It can be seen that oxygen dissolves well in perfluoro solvents. From this data, the removal of hydrogen, which is the cause of pinholes, can be expected by the coexistence of solvents with high gas solubility such as fluorine solvents.

[0008] Furthermore, in order to coexist in an electrochemical reaction field such as fitting, it is estimated that perfluoroalkyl solvents are suitable in this respect as well. The

[0009] Given the above, it is presumed that if a coexisting hydrophobic solvent dissolves and removes bubbles generated on a substrate during an electrochemical reaction, a metal film can be formed without pinholes. Furthermore, the surface tension of a general organic solvent is lower than that of an aqueous metal salt solution. In particular, the surface tension of the electrolyte solution as a whole is reduced if an emulsified state can be formed because the intermolecular force of a fluorine solvent is small. For this reason, if surface treatment such as plating is performed in the emulsified state formed with the aqueous solution of metal salt and hydrophobic solvent in the presence of a surfactant, it is possible to uniformly treat the inside of the microstructure. .

[0010] Further, since the surfactant solution also has a cleaning effect, it is possible to simplify the steps before and after the surface treatment such as plating, and to reduce waste liquid.

[0011] Furthermore, according to the present method, the amount of squeezed liquid can be reduced by the amount of the mixed hydrophobic solvent, so that it is possible to reduce the metal waste liquid and the waste liquid treatment cost.

[0012] By the way, in chemical plating other than electric plating, hydrogen gas is generated with the deposition of plating, and pinholes are generated. Therefore, the present invention can contribute to pinholeless film formation even in chemical plating.

Based on the above estimation, the present inventors added a hydrophobic solvent having a high gas solubility to the aqueous metal salt solution, and carried out a surface treatment operation in the state of emulsification or turbidity. Invented.

[1] Surface treatment of an object in the presence of an aqueous solution containing a metal salt and a hydrophobic solvent A surface treatment method characterized by the above.

[2] The method according to [1], wherein the surface treatment is performed by emulsifying an aqueous solution containing a metal salt and a hydrophobic solvent under stirring.

[3] The method according to [1] or [2], wherein a surface treatment is further performed by adding a surfactant and emulsifying.

[4] Hydrophobic solvent power The method according to any one of [1] to [3], which is an S fluorine solvent.

[5] The method according to any one of [1] to [3], wherein the hydrophobic solvent is a silicon-based solvent.

[6] The method according to [4] or [5], further comprising adding another organic solvent.

[7] The hydrophobic solvent is a fluorine solvent having a perfluoroalkyl group in the molecule.

The method according to any one of [I] to [4], [6].

[8] The method according to any one of [1] to [4], [6], wherein the hydrophobic solvent is a fluorine solvent having a perfluoropolyether group in the molecule.

[9] A metal film obtained by the method according to any one of [1] to [8].

[10] A method for producing an article having a metal film, which comprises subjecting an object to surface treatment in the presence of an aqueous solution containing a metal salt and a hydrophobic solvent.

[I I] An article having a metal film obtained by the method of [10].

Hereinafter, the present invention will be described in detail.

[0014] As the effective hydrophobic solvent in the present invention, any metal salt aqueous solution and any solvent that can be emulsified can be used. Particularly, gaseous solvents such as fluorine solvents, silicon-based solvents, chlorofluorocarbons, and ionic liquids can be used. A substance having a high solubility (particularly hydrogen) is effective. Furthermore, chemical, physical stability, nonflammability, and low toxicity are required for safety during operation. From this point of view, a low-viscosity perfluoropolyether compound with a particularly low vapor pressure, which is desirable for a fluorine solvent, is desirable. In practice, a low viscosity is desirable in consideration of the efficiency of stirring. A fluorine solvent has a low intermolecular force, and therefore has a low viscosity instead of a molecular weight. From the viewpoint of the above stirring efficiency, U is a desirable solvent.

[0015] The fluorine solvent is a compound in which part or all of the CH bond in the hydrocarbon is replaced with a CF bond. For example, a fluorine solvent having a perfluoroalkyl group in the molecule, perfluoro A fluorine solvent having a polyether group may be mentioned. [0016] Examples of the fluorine-containing solvent having a perfluoroalkyl group include heptafluorocyclopentane, octafluorocyclopentene, perfluoro oral hexane, perfluorodecalin, perfluorotripropylamine, perfluorotetrahydrofuran. And those obtained by electrolytic fluorination or cobalt fluorination such as perfluorodimethylcyclohexane.

[0017] As a fluorine solvent having a perfluoropolyether group, for example, a general formula F- (CF

2

○)-(CF ○)-(CF ○)-(CF ○)-(CF) -CF (where o, p and q are 0 or 1, m 3 6 m 2 4 n 2 p 2 q Three

And n are not 0 at the same time, but are integers from 0 to 50, and n + m≤50. Regardless of the order of each repeating unit,-(C F 0) — is-(CF CF CF 0)-or-(CF (CF) CF O)-,-(C F O

3 6 m 2 2 2 m 3 2 m 2 4

)-Represents-(CF CF0)-or-(CF (CF) 0)-, respectively. ) Perfluoropo η 2 2 η 3 η

A reether compound may be mentioned.

[0018] Other fluorine solvents having a perfluoropolyether group include those represented by the formula: F- (CF)-(OC

2 q 3

F)-(OC F)-(OCF)-(CH)-containing a unit represented by-or a formula:-(CH)-

6 m 2 4 η 2 ο 2 ρ 2 ρ

(CF Ο)-(C F Ο)-(C F Ο)-(CF)-(OC F)-(OC F)-(OCF)-(CH)-

2 ο 2 4 η 3 6 m 2 q 3 6 m 2 4 η 2 ο 2 ρ Examples include compounds containing units. (Where m and η are non-zero integers of 0-50, satisfy n + m≤50, 0 is an integer of 0-20, p is an integer of 0-2, q is 1-10 Regardless of the order of each repeating unit,-(OC F)-is-(OCF CF CF)-or-(

3 6 m 2 2 2 m

OCF (CF) CF)-,-(○ C F)-represents-(OCF CF)-or-(OCF (CF)-

3 2 m 2 4 η 2 2 n 3 n

o)

The above-mentioned fluorine solvent having a perfluoropolyether group can be easily obtained. Examples include Galden (manufactured by Solvay Solexis). In addition, a fluorine-hydrocarbon hybrid type compound having a fluoroalkyl group listed here in its molecule, such as a hydrated fluoroether (HFE), can function effectively.

[0019] The silicon-based solvent is a compound having a polyalkyl cage group in the molecule. For example, a polydialkylsiloxane represented by the formula: (R- (Si (R ′) 0) -R ′ ′ (where R, R ′ and R ′ are

2 n

Each is the same or different and is hydrogen or a hydrocarbon group having 1 to 20 carbon atoms. n represents any positive integer. ); Between the polydialkylsiloxane and other hydrocarbon polymers Copolymer (which may have various substituents); formula (R-Si (OR '), R Si (OR'), or R

3 2 2

Alkoxyalkylsilane represented by Si ○ R, where R and R are hydrogen or charcoal, respectively.

Three

It is a hydrocarbon group having 1 to 20 prime numbers. ) And the like.

[0020] Fluorocarbons include CFC—113, HCFC-13, HCFC—141b, HCFC—225ca, HCFC—225c b and other HCHF, HFC-365mfc, HFC-c-447ef, HFC-43-lOmee, HFC -Examples of HFCs such as 52-13p and HFEs listed above.

[0021] Examples of the ionic liquid include tetraalkyl ammonium, tetraalkyl phosphorous, N

-Alkylpyridium, 1,3-dialkylimidazolium, trialkylsulfo-um as power thione, BF-, PF-, SbF-, NO-, CF SO-, (CF SO) N- , ArSO―, CF CO―,

4 6 6 3 3 3 3 3 2 3 3 2

Examples thereof include organic salts having CH 2 CO 3, Al CI— as a key.

3 2 2 7

[0022] The hydrophobic solvent of the present invention widely includes a solvent that is liquid at room temperature (20 to 25 ° C) and separates from water, and has a viscosity that can be stirred at room temperature. However, a low-viscosity solvent is particularly preferable in order to facilitate stirring. The molecular weight of the hydrophobic solvent is not particularly limited as long as the above conditions are satisfied, but it is, for example, about 250 to 3000.

[0023] Although there is no significant limitation on the composition ratio between the hydrophobic solvent and the metal salt aqueous solution, the surface treatment can be sufficiently performed if the amount of the metal salt aqueous solution is 0.01 wt% or more with respect to the hydrophobic solvent. Therefore, the amount of the hydrophobic solvent with respect to the aqueous metal salt solution can be used in the range of about 1 wt% to 99 wt%, preferably 5 to 95 wt%, and more preferably 10 to 90 wt%.

[0024] The metal salt aqueous solution used in the present invention may be a commercially available product such as a plating solution that does not need to be specially adjusted.

[0025] Examples of the metal salt used in the present invention include Ni, Co, Cu, Zn, Cr, Sn, W, Fe, Ag, Cd, Ga, As, Cr, Se, Mn, In, Sb, Te, Ru, Rh, Pd, Au, Hg, Tl, Pb, Bi, Po, Re, Os, Ir, Pt, etc. are exemplified, and examples of metal salts include water-soluble salts, bromides, iodides, etc. Examples thereof include organic acid salts such as halides, nitrates, sulfates, sulfamates and acetates, cyanides, oxides, hydroxides and complexes. The metal salt may be one metal salt or a combination of two or more metal salts. The concentration of the metal salt can be selected as appropriate according to the metal species, but the practical reaction rate Can be set to 0.01 wt% or more in the metal salt aqueous solution, for example.

[0026] The surface treatment method of the present invention comprises electrolysis or chemical reaction of water such as electroplating, chemical plating, electroplating, anodizing, electropolishing, electrolytic processing, electrophoretic coating, electrolytic polishing, chemical conversion treatment, and the like. This is a treatment method in which bubbles (for example, hydrogen) are generated at the time of removal, and this bubble is removed by dissolving in a hydrophobic organic solvent, and is characterized in that a high-quality film without pinholes is obtained. Here, a film having no pinholes refers to a film having 1 or less pinholes per 1 cm ² in diameter. If there are no bubbles, the metal film can be prevented from hydrogen embrittlement and the film strength can be improved. Preferred surface treatments are electroplating, chemical plating, anodizing, electroplating, electropolishing, electrolytic processing, electrolytic polishing, and electrophoretic coating.

In the present invention, the addition of a surfactant to emulsify the hydrophobic solvent and the aqueous metal salt solution affects the surface treatment efficiency. Even if a surfactant is not added, it can be electroplated. By adding force, it can be very efficient. As the surfactant, many conventionally known compounds can be used, including non-one, ar-on, cationic and zwitterionic surfactants, and these constituent elements are also hydrocarbon-based. , Silicon-based, fluorine-based, etc., and at least one of them can be selected and used. The concentration of the surfactant is not particularly limited. For example, it may be about 0.0001 to 20 wt%, preferably about 0.001 to 10 wt% with respect to the aqueous metal salt solution!

[0028] Preferable surfactants include fluorine-based surfactants, silicon-based surfactants, and hydrocarbon-based surfactants, and more preferable are fluorine-based surfactants and silicon-based surfactants.

[0029] Specific examples of the surfactant are described below.

[0030] The fluorine-based surfactant is a surfactant having a polyfluoroalkyl in which at least one of the alkyl hydrogen atoms is substituted with a fluorine atom, and examples thereof include polyfluoroalkylsulfonates and polyfluoroalkylcarboxylic acids. Acid salt, polyfluoroalkylbenzenesulfonate, polyfluoroalkyl sulfate, polyfluoroalkyl ether sulfate, polyfluorophenyl ether sulfate, polyfluoroalkyl of sulfosuccinate Derivatives and other key-on compounds; Realkylene glycol, polyfluoroalkylol amide, polyfluoro higher alcohol, polyfluoro fatty acid ester, polyfluoropolyether carboxylic acid ester, polyfluoroalkylamine ethylene oxide case, polyfluoroalkyl carboxylic acid, Nonionic compounds such as polyfluoropolyether carboxylic acids; Cationic compounds such as monopolyfluoroalkyl ammonium halides, dipolyfluoroalkyl ammonium halides, tripolyfluoroalkyl ammonium halides; polyfluoroalkyls Examples include amphoteric compounds having both cation ions in the molecule, such as betaine. Of these, non-one compounds are preferred. The above polyfluoroalkyl includes perfluoroalkyl in which all of the alkyl hydrogen atoms are substituted with fluorine atoms.

[0031] Examples of the silicon surfactant include polyalkylene glycol, polyol, ester, amide, amino alcohol, alkyl ammonium, alkyl sulfonate, alkyl carboxyl, alkyl phosphate, and the like. Examples thereof include polydimethylsiloxanes having groups and polyalkoxyalkylsilicones. Of these, polydimethylsiloxanes or polyalkoxyalkylsilicones having a group containing polyalkylene glycol are preferred.

[0032] Examples of the hydrocarbon-based surfactant include α-olefin sulfonate, alkyl benzene sulfonate, alkyl sulfate ester salt, alkyl ether sulfate ester salt, sulfosuccinate, phosphate ester, ether sulfone. Acid salts, alkylphenols, higher alcohols, polyols, polyalkylene glycols, alkylolamides, fatty acid esters, fatty acid amines, alkylamine ethylene oxide adducts, lauryl trimethyl ammonium salts, stearyl trimethyl ammonium salts Hexadecyl pyridi-um salt, imidazolium betaine and the like. Of these, polyalkylene glycol is preferred.

In the surface treatment, the temperature and pressure are not particularly limited, and it is not always necessary to heat or pressurize. It is possible to carry out in the range of temperature and pressure required for normal surface treatment.

[0034] The temperature of the surface treatment step may be about 0 ° C to 200 ° C. For example, in the case of electrical plating, the plating temperature depends on the metal, and is about room temperature (20 ° C) to 100 ° C. example For example, it is from room temperature to 80 ° C for nickel and gold, 30 ° C to 70 ° C for palladium, room temperature to 70 ° C for copper, and 50 ° C to 100 ° C for platinum.

[0035] The pressure in the surface treatment process may be less than 10 atm. In order to avoid an increase in pressure due to vaporization of the solvent at the processing temperature, a high boiling point solvent should be used when processing at a high temperature. From the viewpoint of safety, it is desirable to perform the surface treatment at 1 to 2 atmospheres by setting such treatment conditions.

Furthermore, the following organic solvents (cosolvents) can also be added. For example, alcohols such as methanol, ethanol, propanol, butanol and pentanol; ketones such as acetone; acetonitrile; esters such as ethyl acetate; ethers such as ethyl ether; chlorofluorocarbons; Halides and the like can be mentioned, and those having low toxicity and particularly low toxicity are desirable. When an organic solvent is added, the amount added is 50 wt% or less, preferably about 5 to 10 wt%, based on the hydrophobic solvent.

[0037] In the present invention, since the system is a two-phase system, stirring is required. Here, the stirring includes magnetic stirring, mechanical stirring, or mixing by ultrasonic irradiation. The specific number of revolutions varies depending on the type of hydrophobic solvent and metal salt aqueous solution, the scale of the apparatus, and the stirring method, and therefore must be optimized during actual operation.

[0038] For example, in the case of magnetic stirring or mechanical stirring, 100 ~: LOOOOOrpm, preferably 400 ~: LOOOrpm force S is exemplified, and in the case of ultrasonic irradiation, 20kHz ~ 10MHz is exemplified.

[0039] The thickness of the metal film formed by the surface treatment of the present invention is a force that can be appropriately selected depending on the application, plating conditions, etc. For example, about lnm to 1000 μm, preferably about 10 nm to 100 μm. .

[0040] The material of the object to be surface-treated is not particularly limited, and examples thereof include metals, alloys, ceramics, plastics, glasses, and conductive polymers. In the case of non-conductive materials (for example, plastics). Examples include those subjected to surface treatment such as attaching metal particles to the surface. Examples of the shape of the object to be surface-treated include a plate shape, a granular shape, a spherical shape, a curved surface shape, and a cylindrical shape, and the treatment liquid containing the metal salt aqueous solution and the hydrophobic solvent is sufficiently supplied with stirring. The shape is preferred.

The invention's effect [0041] According to the surface treatment method of the present invention, a high-quality metal film can be easily formed on an object. As a result, an article having a high-grade metal film can be produced. In addition, the amount of waste liquid such as heavy metals generated during the surface treatment is smaller than that of the existing electrochemical surface treatment.

Brief Description of Drawings

FIG. 1 shows an SEM photograph (magnification 500 times) showing the plating film obtained in Example 1.

FIG. 2 shows an SEM photograph (magnification 5000 times) showing the plating film obtained in Example 1.

FIG. 3 shows an SEM photograph (magnification 50000 times) showing the plating film obtained in Example 1.

FIG. 4 shows an SEM photograph (multiplier 500 times) of the normal bright nickel plating (thickness 5 microns) obtained in Comparative Example 1.

FIG. 5 shows a photograph of the sample obtained in Example 4.

FIG. 6 shows a photograph of the sample obtained in Example 5.

FIG. 7 shows an SEM photograph (magnification 60 times) showing the plating film obtained in Example 6.

FIG. 8 shows an SEM photograph (magnification 1000 times) showing the plating film obtained in Example 6.

FIG. 9 shows an SEM photograph (magnification: 10,000 times) showing the plating film obtained in Example 6.

FIG. 10 shows an SEM photograph (magnification 1000 times) showing the plating film obtained in Example 8.

FIG. 11 shows an SEM photograph (magnification 110 times) showing the plating film obtained in Example 9.

FIG. 12 shows an SEM photograph (1000 × magnification) showing the plating film obtained in Example 9.

FIG. 13 shows an SEM photograph (magnification 20000 times) showing the plating film obtained in Example 9. BEST MODE FOR CARRYING OUT THE INVENTION

[0043] Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

[Example 1] Nickel electrolytic plating

In a beaker with an internal volume of 50 cc, nickel plating solution (watt bath: nickel sulfate 280 g / L, nickel chloride 60 g / L, boric acid 50 g / L, brightener appropriate amount) 20 mL, and Perfluorohexane 20 mL F (CF (CF) CF O) CF (CF) COOCH CH OCH

0.1 wt% of 3 2 3 3 2 2 3 was added, a degreased brass plate was attached to the cathode, and a pure nickel plate (4 cm ² each surface area) was attached to the anode. The temperature of the mixture was raised to 50 ° C in a thermostatic bath. On the stirrer These were emulsified by fixing and rotating the rotor at 500 rpm. Nickel plating was performed by energizing at 5 A / dm ² for 0.5 minutes. After energization, the cathode plate was taken out, thoroughly washed with water, and the surface was observed with a microscope. The film thickness was 0.5 microns. Photomicrographs are shown in Figs.

[0044] As is apparent from FIG. 1, no pinhole is detected. In addition, as can be seen from the high-magnification images (5,000 and 50,000 times, respectively) obtained by SEM in Figs. 2 and 3, a dense film can be formed with very fine crystals. This is probably because the gas generated on the substrate was dissolved and removed in the fluorocarbon solvent.

[Comparative Example 1] Bright nickel plating

A nickel plating solution (Watt bath) 40 mL was placed in a beaker having an internal volume of 50 cc similar to that in Example 1, and a brass plate as a cathode and a pure nickel plate (a surface area of 4 cm ² each) were attached from the top of the container. The solution was heated to 50 ° C., and stirred with a magnetic stirrer (500 r.p. m) for 5 minutes at 5 A / dm ² to conduct nickel plating. After the post-treatment similar to that in Example 1, the obtained plated film was observed by SEM. Figure 4 shows a photomicrograph of normal bright nickel plating (5 micron thick).

[0045] From FIG. 4, it was found that when a film having a thickness of 5 microns or less is formed with ordinary electric plating, many pinholes are generated.

[Example 2] Nickel electrolytic plating

In a mixture of 30 mL of the same nickel plating solution as in Example 1 and 20 mL of perfluorodimethylcyclohexane, H (CF) CH OCOCH CH (SO Na) COOCH (CF) H as a surfactant

0.04 wt% was added to 2 4 2 2 3 2 2 4. Nickel plating was applied to the brass plate under the same conditions as in Example 1.

[Example 3] Nickel electrolytic plating

F (CF (CF) CF O) CF (CF) CO (OCH CH) OCH as a surfactant was added to a mixture of 30 mL of the same nickel plating solution as in Example 1 and 20 mL of perfluorodimethylcyclohexane.

3 2 3 3 2 2 7 3 Plating was performed with 0.04 wt% of plating solution. A nickel film similar to that in Example 1 was formed.

[Example 4] Electroless copper plating (1) Catalyst loading process

Polypropylene reagent bottle lid-A part of a disc (diameter 3Φ) was placed on the bottom of the high-pressure apparatus, and 16 mg of organic platinum complex (1,5-cyclooctadiene) dimetylplatinum (II) was placed in this container and sealed. Thereafter, carbon dioxide was introduced, treated at 30 MPa and 120 ° C for 15 hours, then heated to 130 ° C and maintained for 3 hours to activate the catalyst. After decompression, the sample was taken out and washed with water followed by methanol. An active platinum catalyst supported on the sample surface in black was confirmed.

(2) Plating process

Place the above sample in a 50 mL beaker similar to Example 1, and add 30 mL of copper electroless solution (C-200LT, High-Purity Chemical Laboratory Co., Ltd.) and 20 mL of perfluorodimethylcyclohexane. And add F (CF (CF) CF O) CF (C

3 2 3

F) COOCH CH OCH was added in an amount of 0.6 wt% with respect to the solution. 50 this reaction. 15 minutes on C

3 2 2 3

Stir. The sample was washed with water and the surface was observed. Fig. 5 shows a photograph of the mating sample.

[Example 5] Electroless copper plating

A 2.5cm thick plate (thickness 0.5mm) sample made of the same material as in Example 4 was washed with acetone, dried, then treated with chromic acid-sulfuric acid solution at 60 ° C for 15 minutes to roughen the surface. Turned into. This was immersed in a 0.5 mM-PdCl-0.05 mM-SnCl solution for 30 minutes. After washing with water, the sample is

twenty two

Place in a similar 50 mL beaker, and add 30 mL of copper electroless plating solution (C-200LT, High Purity Chemical Laboratory Co., Ltd.) and 20 mL of perfluorodimethylcyclohexane to this solution. F (CF (CF) CF O) CF (CF) COOCH CH OCH as a surfactant

3 2 3 3 2 2 3 It was 0.6wt% with respect to the attached liquid. The reaction was stirred at 50 ° C for 15 minutes. The sample was washed with water and the surface was observed. Fig. 6 shows a photograph of the mating sample.

[Example 6] Electrolytic palladium plating

Add a palladium plating bath (10 g / L of salty palladium to an aqueous solution of ethylenediamine 10 g / L to a beaker with an internal volume of 50 cc, and heat at 60 ° C to make a uniform solution. Add 2N hydrochloric acid to this solution. The pH was adjusted to 3.) 30 mL and perfluorodimethylcyclohexane 20 mL were added, and F (CF (CF) CF 2 O) CF (CF 3) CO (0

3 2 3 3

CH 2 CH 2 OCH was added in an amount of 0.6 wt% with respect to the solution. Degreased brass plate on the cathode, on the anode Titanium plates (4 cm ² surface area each) were attached. The temperature of this mixture was raised to 60 ° C in a thermostatic bath. These were emulsified by fixing on a stirrer and rotating the rotor at 500 rpm. Nickel plating was performed by energizing at ^{2 A} / dm ² for 0.5 minutes. After energization, the cathode plate was taken out, washed thoroughly with water, and the surface was observed with a microscope. Figures 7 to 9 show SEM photographs. A very dense film with fine crystal grains and no pinholes is formed. In addition, it can be traced into the groove of the Hull cell substrate, and the attachment is very good.

[Example 7] Electrolytic palladium plating

Palladium plating similar to that in Example 6 was performed using an alkaline bath (Nihon Electo Porting Engineers Co., Ltd., Paradex LF-2) as the plating solution. The obtained plating film was slightly less uniform than Example 6. A better trend was observed in the acidic bath.

[Example 8] Electrolytic copper plating

High purity chemical laboratory Co., Ltd.—30 mL of C-100ES and 20 mL of perfluorodimethylcyclohexane were added as a copper plating solution. Further, F (CF (CF) CF O) CF ( CF 3) CO (OCH 2 CH 3) OCH was added in an amount of 0.6 wt% with respect to the solution. True to cathode

3 2 3 3 2 2 2 3

A brass plate and a titanium plate (surface area 4 cm ² each) were attached to the anode, emulsified with stirring, and then energized at 50 ° C. and 2 A / dm ² for 0.5 minutes to perform copper plating. Figure 10 shows the SEM photograph. A uniform and pinhole-free film can be obtained!

[Example 9] Electrolytic gold plating

Acid gold plating solution (High Purity Chemical Laboratories, Inc., Pure Pure Electrolytic Solution K-24EA10) For 30 mL, add 20 mL of perfluorodimethylcyclohexane, and then add F ( CF (CF) CF O) CF (CF) COOCH CH OCH

3 2 3 3 2 2 3

Yeah. A brass plate was attached to the cathode of the plating tank and a titanium plate with a platinum coating on the anode (each surface area of 4 cm ² ) was immersed in the plating solution while energized, and the lid was closed. Stirring was started to emulsify the perfluorinated solvent, and then energized at 0.5 A / dm ² for 170 seconds at 50 ° C (voltage during energization: approx. 3 V), and gold plating was performed (film thickness: 0.7). Figures 11 to 13 show SEM photographs. A uniform film without pinholes was obtained.

[Example 10] Electrolytic gold plating F (CF (CF) CF O) CF (CF) COOH as a surfactant was added to lOmg as a surfactant in a mixed solution of 30 mL of gold plating solution similar to Example 9 and 20 mL of florinate (FC-77), Similar to Example 9

3 2 3 3

The operation was performed.

[Example 11]

As in Example 1, 30 mL of nickel plating solution and CF [(OCF (CF) CF) (OCF)] OCF (o

3 3 2 x 2 y 3 Rigomer mixture, boiling point = 135 ° C) F (CF (CF) CF as a surfactant in a 20 mL mixture

Three

O) CF (CF) COOCH CH Add 20 mg of OCH, 3 minutes at 50 ° C, current density 5A / dm ²

2 3 3 2 2 3

Power was applied and nickel plating was performed.

As described in the above embodiments, according to the present invention, even a very thin thin film can be formed with 1 or less pinholes having a diameter of 1 μm or more per 1 cm ² .

Claims

The scope of the claims

[I] A surface treatment method characterized by subjecting an object to surface treatment in the presence of an aqueous solution containing a metal salt and a hydrophobic solvent.

[2] The method according to claim 1, wherein the surface treatment is carried out by emulsifying an aqueous solution containing a metal salt and a hydrophobic solvent under stirring.

[3] The method according to claim 1 or 2, wherein a surfactant is further added and emulsified to effect surface treatment.

[4] Hydrophobic solvent power The method according to any one of claims 1 to 3, which is an S fluorine solvent.

[5] The method according to any one of claims 1 to 3, wherein the hydrophobic solvent is a silicon-based solvent.

6. The method according to claim 4 or 5, further comprising adding another organic solvent.

[7] The method according to any one of claims 1 to 4, wherein the hydrophobic solvent is a fluorine solvent having a perfluoroalkyl group in the molecule.

[8] The method according to any one of [1] to [4] and [6], wherein the hydrophobic solvent is a fluorine solvent having a perfluoropolyether group in the molecule.

[9] A metal film obtained by the method according to any one of claims 1 to 8.

[II] An article having a metal film obtained by the method according to claim 10.