EP3296432A1 - Porous nickel thin film and manufacturing method thereof - Google Patents
Porous nickel thin film and manufacturing method thereof Download PDFInfo
- Publication number
- EP3296432A1 EP3296432A1 EP16862129.0A EP16862129A EP3296432A1 EP 3296432 A1 EP3296432 A1 EP 3296432A1 EP 16862129 A EP16862129 A EP 16862129A EP 3296432 A1 EP3296432 A1 EP 3296432A1
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- Prior art keywords
- thin film
- nickel
- nickel thin
- pushing jig
- jig
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D1/00—Electroforming
- C25D1/08—Perforated or foraminous objects, e.g. sieves
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D1/00—Electroforming
- C25D1/04—Wires; Strips; Foils
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/12—Electroplating: Baths therefor from solutions of nickel or cobalt
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/18—Electroplating using modulated, pulsed or reversing current
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/48—After-treatment of electroplated surfaces
- C25D5/50—After-treatment of electroplated surfaces by heat-treatment
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/60—Electroplating characterised by the structure or texture of the layers
- C25D5/623—Porosity of the layers
Definitions
- the present invention relates to a porous nickel thin film and a manufacturing method thereof.
- Nickel thin films are expected to be applied to numerous fields.
- Patent Literature 1 Japanese Patent No. 4411409 (Patent Literature 1) describes that a porous nickel plated film is used as a support for a hydrogen permeable metal membrane.
- Patent Literature 1 describes that a porous nickel plated film is used as a support for a hydrogen permeable metal membrane.
- flexibility is required in a nickel thin film.
- Patent Literature 1 Japanese Patent No. 4411409
- An object of the present invention is to provide a nickel thin film excellent in flexibility and a manufacturing method thereof.
- the inventors have found that a porous nickel thin film obtained by using a particular method greatly surpasses in flexibility a nickel thin film obtained by using the conventional method.
- the present invention includes the following aspects:
- the present invention provides a nickel thin film excellent in flexibility and a manufacturing method thereof.
- Fig. 1A to Fig. 1D are cross-sectional views schematically showing a method of manufacturing a porous nickel thin film according to the embodiment.
- a conductive substrate 1 is prepared.
- a nickel plated film 2 is formed on the conductive substrate 1.
- the nickel plated film 2 is formed using a nickel electroplating bath which contains a nickel salt and a surfactant. Since the nickel electroplating bath contains a surfactant here, the nickel plated film 2 formed has the surfactant taken therein.
- the nickel plated film 2 is heat-treated. Heat treatment burns and removes the surfactant taken in the nickel plated film 2. Then, pores 4 penetrating in the thickness direction are formed in the nickel plated film 2, and a porous nickel thin film 3 is obtained as a result.
- the nickel thin film 3 is peeled off the conductive substrate 1 as shown in Fig. 1D .
- a substrate with low adhesion to the nickel thin film 3 as the conductive substrate 1.
- a substrate includes a metal substrate such as for example a Ti substrate, a Cu substrate, and an SUS substrate, and glass and resin material which are given electrical conductivity. Note that heat treatment for removing the surfactant may be carried out after the nickel thin film 3 is peeled off the conductive substrate 1.
- the nickel thin film 3 does not necessarily have to be peeled off the conductive substrate 1.
- the nickel thin film 3 may be peeled off the conductive substrate 1.
- the porous nickel thin film 3 which is excellent in flexibility.
- the porous nickel thin film 3 which has a flexibility value of 15.0 N/mm or less, preferably 10.0 N/mm or less, more preferably 1.0 to 10.0 N/mm, and still more preferably 3.0 to 8.0 N/mm.
- the porous nickel thin film 3 having such flexibility values is a novel metal film obtainable by the manufacturing method of the present invention, excellent in flexibility, and useful in various applications.
- the "flexibility value" in the present specification can be determined by the method of evaluating the porous nickel thin film and the method explained in Examples to be described later.
- the porous nickel thin film 3 obtained in the embodiment is also excellent in thermal resistance. There is a case where the shape of a nickel thin film manufactured by e.g. rolling is not maintained because oxidation proceeds during high temperature heating. In contrast, the shape of the porous nickel thin film 3 obtained in the embodiment is maintained even during high temperature heating.
- the thickness of the nickel thin film 3 obtained in the embodiment is preferably 0.1 ⁇ m to 100 ⁇ m, more preferably 1 ⁇ m to 10 ⁇ m, and still more preferably 2 ⁇ m to 8 ⁇ m. Too large a thickness makes it difficult to form pores, raises the processing difficulty, and leads to an increase in the manufacturing cost. Conversely, too small a thickness leads to insufficient strength.
- the use of the nickel thin film 3 obtained in the embodiment is not particularly limited.
- the nickel thin film 3 is useful as: a high performance catalytic film; a high performance filter; an undercoat for coating, painting, and plating; a functional coat and a thermal radiation coat used at high temperatures; and a surface coat for a slidable component.
- the nickel thin film 3 is used as-is, or catalytic particles such as Pt and Pd particles are scattered and held in the pores of the nickel thin film 3.
- the penetration pores formed in the nickel thin film 3 are used as fluid passages.
- flexibility is important in terms of the life of the coat.
- the nickel thin film 3 of the embodiment is preferable because it can satisfy such a requirement.
- the nickel thin film 3 obtained in the embodiment is useful as a functional coat and a thermal radiation coat which are required to have thermal resistance because it is not broken even under a high temperature atmosphere.
- the nickel thin film 3 of the embodiment has a large surface area because it is provided with pores. For this reason, if the nickel thin film 3 is used as an undercoat for e.g. coating, painting, and plating, it is possible to increase physical adhesion between the nickel thin film 3 and a film formed thereon.
- the nickel thin film 3 of the embodiment is used as a surface coat of a slidable component, it is possible to enhance lubricant retainability and to extend the life of the slidable component thanks to the pores provided.
- the plating bath used in the embodiment is an aqueous solution containing a nickel salt and a surfactant.
- the nickel salt acts as a supply source of nickel ions.
- the nickel salt is not particularly limited, it is preferable to use a compound selected from the group consisting of nickel sulfamate, nickel chloride, nickel sulfate, and nickel citrate.
- the nickel salt preferably contains nickel sulfamate. A coating with a low internal stress and high flexibility is obtained by use of nickel sulfamate.
- the concentration of the nickel salt in the plating bath is preferably 100 g/L to 800 g/L. Too high a concentration of the nickel salt reduces the saturation concentration of the surfactant, makes it difficult to form pores, and increases the possibility of losing flexibility. Too low a concentration of the nickel salt reduces the limiting current density due to insufficient concentration of the metal salt, increases the possibility of producing hydrogen gas during the formation of the coating, and increases the risk of cracks caused by the occlusion of hydrogen into the conductive substrate 1 being the undercoat. Moreover, too low a concentration is likely to produce a rough Ni plated coating with numerous pinholes.
- an ionic surfactant as the surfactant contained in the plating bath. It is preferable to use an anionic surfactant as the ionic surfactant.
- anionic surfactant examples include a compound selected from the group consisting of a polyoxyalkylene alkyl ether sulfate, a polyoxyalkylene alkyl ether carboxylate, a polyoxyalkylene alkyl ether sulfosuccinate, a polyoxyalkylene alkyl ether phosphate, a polyoxyalkylene alkyl ether acetate, an alkylbenzene sulfonate, a higher alcohol sulfate, a polyoxyalkylene styrenated phenyl ether sulfate, an alkyl diphenyl ether sulfonate, an alpha olefin sulfonate, a dialkyl sulfosuccinate, an alkane sulfonate, a secondary alkane sulfonate, an alkyl naphthalene sulfonate, a formaldehyde condens
- a more preferable compound is one selected from the group consisting of the polyoxyalkylene alkyl ether sulfate, the polyoxyalkylene alkyl ether carboxylate, the polyoxyalkylene alkyl ether acetate, and the alkylbenzene sulfonate among the above.
- each of the polyoxyalkylene alkyl ether sulfate and the polyoxyalkylene alkyl ether carboxylate is preferably an ethylene oxide-containing compound expressed by Formula 1 below: (Formula 1) : R1-O-(CH 2 CH 2 O) n -X
- R1 represents an alkyl group, preferably an alkyl group having 10 to 16 carbon atoms, and more preferably an alkyl group having 12 to 14 carbon atoms.
- the letter X indicates a sulfate or a carboxylate.
- the letter n ranges from 1 to 20, preferably from 2 to 12.
- alkylbenzene sulfonate is preferably a compound having 8 to 16 carbon atoms in the alkyl group, more preferably a dodecylbenzene sulfonate.
- the counter ions used as the salt of the anionic surfactant include alkali metal salts such as a sodium salt and a potassium salt, alkali earth metal salts, ammonium salts, and alkanolamine salts. Among these, the alkali metal salts are preferable, and the sodium salt is more preferable.
- the concentration of the surfactant in the plating bath is preferably 0.1 mL/L to 100 mL/L, more preferably 1 mL/L to 50 mL/L, and still more preferably 5 mL/L to 30 mL/L. Too high a concentration of the surfactant makes it difficult to obtain a fine coating because plate deposition is hindered. On the other hand, too low a concentration makes it difficult to form pores, which makes it hard to obtain desired flexibility.
- additives may be added to the plating bath such as a pH adjuster, a pH buffer, and a stress releaser.
- a pH adjuster e.g., Sulfuric acid, sulfamic acid, nickel hydroxide, etc.
- Saccharin etc. are used as the stress releaser, for example.
- the pH of the plating bath is preferably 2.0 to 4.5. Too high a pH reduces the limiting current density, increases the possibility of producing hydrogen gas, and increases the risk of occlusion of hydrogen into the conductive substrate 1. Moreover, the Ni coating is likely to become hard and brittle. On the other hand, too low a pH is likely to promote decomposition of the plating bath components.
- the bath temperature of the plating bath during plating is preferably 40°C to 65°C. Too high a bath temperature is likely to promote the decomposition of the bath components. On the other hand, too low a bath temperature increases the possibility of surfactant precipitation. Moreover, extraneous deposition of nickel is likely to take place.
- electroplating is possible using a direct current electrolysis, it is more preferable to carry out pulse electroplating.
- pulse electroplating at the early stages of deposition, it is possible to cause the surfactant to scatter and be adsorbed to the conductive substrate 1 being the undercoat, and to promote eutectoid between the surfactant and nickel during plating.
- the average current density is preferably 1 A/dm 2 to 20 A/dm 2 . Too high an average current density may lead to excessive production of hydrogen, affecting the conductive substrate 1 being the undercoat. Furthermore, extraneous deposition of nickel might take place. On the other hand, too low an average current density makes it difficult to form pores, which makes it hard to obtain desired flexibility. Also, productivity is reduced.
- the pulse current density is preferably 2 A/dm 2 to 20 A/dm 2 . Too high a pulse current density may cause excessive production of hydrogen, affecting the conductive substrate 1 being the undercoat. Furthermore, extraneous deposition of nickel might take place. On the other hand, too low a pulse current density makes it difficult to form pores, reducing productivity.
- the ratio of the pulse applying time ton to the pulse pause time toff is more preferably 0.1 to 10. Too large a ratio (ton/toff) makes it difficult to form pores, which makes it hard to obtain desired flexibility. Conversely, too small a ratio also makes it difficult to form pores, which makes it hard to obtain desired flexibility.
- the pulse frequency is preferably 0.1 to 1000 (Hz) . Too large a pulse frequency makes it difficult to form pores, which makes it hard to obtain desired flexibility. Conversely, too small a pulse frequency also makes it difficult to form pores, which makes it hard to obtain desired flexibility.
- Heat treatment is carried out under the conditions where the surfactant is burnt and removed in, for example, the atmosphere, a reducing atmosphere such as hydrogen, or an inactive atmosphere such as nitrogen or argon.
- the heat treatment temperature is 350°C to 900°C, for example.
- the heating time is 10 minutes to 120 minutes, for example. Too high a heating temperature is likely to increase the cost of mass production processing. Worse, the possibility of losing flexibility is increased because an interdiffusion layer is likely to be formed between the conductive substrate 1 being the undercoat and the nickel plated film 2. On the other hand, too low a heat treatment temperature makes it difficult for porosification to occur, which makes it impossible to obtain desired flexibility. In addition, too long a heating time also increases the possibility of forming an interdiffusion layer. Conversely, too short a heating time makes it difficult for porosification to occur, increasing the possibility of losing flexibility.
- the nickel thin film 3 which is manufactured by the method according to the embodiment has a property excellent in flexibility.
- the "flexibility value” is a value determined using an evaluation method to be described below.
- Fig. 2 is a view of an external appearance of an evaluation apparatus 10 used in the evaluation method for the flexibility value.
- Fig. 3 is a schematic view showing the evaluation apparatus 10.
- the evaluation apparatus 10 includes a body part 16, a stage 11, a pushing jig support 13, a measurement apparatus 18, a pushing jig 14, a subject supporting jig 12, and a drive mechanism 15. Note that the pushing jig 14 and the subject supporting jig 12 are detachable and illustrated only in Fig. 3 , not in Fig. 2 .
- the stage 11 is provided to support the subject supporting jig 12, and is supported by the body part 16.
- the subject supporting jig 12 is provided to support the nickel thin film 3 to be tested (see Fig. 3 ).
- the subject supporting jig 12 is detachably attached to the stage 11.
- Fig. 4 is a cross-sectional view schematically showing the subject supporting jig 12.
- the subject supporting jig 12 includes a pair of clamping members (12-1 and 12-2) .
- One clamping member 12-1 has an opening 17 provided therein.
- the other clamping member 12-2 has a hollow portion 16 provided at the position corresponding to the opening 17.
- Each of the opening 17 and the hollow portion 16 has the shape of a circle with a predetermined diameter of a. Note that the clamping member 12-2 may be provided with an opening instead of the hollow portion 16.
- each clamping member (12-1 and 12-2) is provided with a screw thread (19-1 and 19-2), and it is thus possible to threadly engage the clamping member 12-1 with the clamping member 12-2 while clamping the nickel thin film 3.
- the center portion of the nickel thin film 3, that is, the region corresponding to the opening 17 is not in contact with the subject supporting jig 12. That is to say, the subject supporting jig 5 is configured to support the entire periphery of the nickel thin film 3, and an unsupported region with a closed shape corresponding to the opening 17 is formed in the center portion of the nickel thin film 3.
- the pushing jig support 13 (see Fig. 2 and Fig. 3 ) is provided to support the pushing jig 14.
- the pushing jig support 13 is attached to the body part 16 so as to be movable in a direction perpendicular to the nickel thin film 3.
- the drive mechanism 15 is attached to the body part 16 and has a function of causing the pushing jig support 13 to travel.
- the drive mechanism 15 is a motor, for example.
- the pushing jig 14 has the shape of a rod.
- the pushing jig 14 is supported above the nickel thin film 3 by the pushing jig support 13 so as to extend in a direction perpendicular to the nickel thin film 3.
- one end (lower end) of the pushing jig 14 is set so as to be positioned right above the center of the opening 17 provided in the clamping member 12-1.
- Fig. 5 is a schematic view showing an example of the pushing jig 14. As shown in Fig. 5 , one end of the pushing jig 14 preferably has a shape corresponding to a portion of a sphere with a predetermined diameter of b.
- the measurement apparatus 18 has a function of detecting the force applied to the pushing jig 14 and the displacement amount of the pushing jig 14.
- the measurement apparatus 18 includes a load cell 18-1 and an encoder 18-2.
- the load cell 18-1 is provided between the pushing jig support 13 and the pushing jig 14 and has a function of detecting the force applied to the pushing jig 14.
- the encoder 18-2 is connected to the drive mechanism 15 and is configured to detect the displacement amount of the pushing jig support 13, that is, a displacement amount of the pushing jig 14.
- the drive mechanism 15 moves the pushing jig support 13 downwards (toward the subject supporting jig 12). This pushes one end of the pushing jig 14 aligned with the center of the opening 17 perpendicularly into the nickel thin film 3, as shown in Fig. 6 .
- the pushing jig 14 is pushed in until the nickel thin film 3 is torn.
- the measurement apparatus 18 measures the force applied to the pushing jig 14 and the displacement amount of the pushing jig 14.
- the measurement results are stored in e.g. a computer (not shown) as data indicating the relationship between the force applied to the pushing jig 14 and the displacement amount of the pushing jig 14.
- the flexibility value of the nickel thin film 3 is determined based on the obtained data.
- the "flexibility value” is a value expressed by a value (N/mm) which is the force (N) applied to the pushing jig divided by the displacement amount (mm) of the pushing jig. The smaller this value, the more flexible the nickel thin film 3 is.
- the flexibility value can be calculated by creating a graph with the horizontal axis representing the displacement amount and the vertical axis representing the force (test force) applied to the pushing jig 14, and by determining the gradient within a range where the linearity is good (for example, a region where the correlation coefficient R 2 determined by linear approximation is larger than 0.9).
- the evaluation method described above makes it possible to properly evaluate the flexibility of the nickel thin film 3 with a thickness of 0.1 to 100 ⁇ m.
- the diameter a of the opening 17 provided in the clamping member 12-1 is preferably 9 mm to 14 mm, more preferably 10 mm to 13 mm, and still more preferably 11 mm to 12 mm. Too small a diameter a makes it impossible to obtain a sufficient displacement amount for the test force, while a too large a diameter requires a large sample area.
- the shape of one end of the pushing jig 14 is preferably a shape corresponding to a portion of a sphere with a diameter of b, as already described.
- the pushing jig 14 touches the test piece at the vertexes. This increases the risk of tearing the test piece before the completion of the test because the test force concentrates at the vertexes. As a result, it becomes difficult to create a region with a high-linearity relationship in the test force-displacement amount graph.
- the shape of one end of the pushing jig 14 is a flat-plate shape such as a flat plate circle, the test piece deforms to make an acute angle at an edge of this flat-plate shape. For this reason, it becomes difficult to obtain a high-linearity relationship.
- the shape of one end of the pushing jig 14 has a shape corresponding to a portion of a sphere, one obtains an effect of pushing the test piece with a surface.
- the pushing jig 14 is being pushed in, the test piece is smoothly stretched while making an obtuse angle. This helps to obtain a higher-linearity relationship.
- the diameter b is preferably 5 mm to 10 mm, more preferably 6 mm to 9 mm, and still more preferably 7 mm to 8 mm. Too small a diameter b means that the test piece is pressed at a point, increasing the risk that the test piece is easily torn. On the other hand, too large a diameter b means that the subject supporting jig 12 also needs to be large, increasing the necessary sample area.
- the ratio of the diameter b to the diameter a of the opening 17 is preferably 0.3 to 0.9, more preferably 0.4 to 0.8, and still more preferably 0.5 to 0.7.
- the ratio of the diameter b to the diameter a within such ranges helps to obtain a high-linearity relationship.
- the push rate of the pushing jig 14 is preferably 0.1 mm/min to 10.0 mm/min, more preferably 0.5 mm/min to 5.0 mm/min, and still more preferably 1.0 mm/min to 2.0 mm/min. Too low a push rate requires a long time test. On the other hand, too high a push rate increases the risk of breaking the test piece, and the test piece is likely to be broken before a region with a high linearity is sufficiently obtained.
- An SUS substrate was prepared as the conductive substrate 1 being the undercoat.
- the nickel plated film 2 was formed on this conductive substrate 1 by electroplating.
- the aqueous solution used as the electroplating bath contained 600 g/L of nickel sulfamate, 10 g/L of nickel chloride, 40 g/L of boric acid, and 10 ml/L of anionic surfactant (sodium dodecylbenzenesulfonate).
- the pH of the plating bath was 3.5, and the bath temperature was 60°C.
- the electroplating was carried out by pulse plating. Pulse plating was carried out under the conditions that the average current density was 5.9 A/dm 2 and the ratio (ton/toff) was 1.4.
- the nickel plated film 2 was peeled off the conductive substrate 1. Furthermore, heat treatment was carried out at 500°C on the nickel plated film 2 for 60 minutes in the atmosphere, and the nickel thin film 3 according to Example 1 was obtained. The thickness of the obtained nickel thin film 3 was 5 ⁇ m.
- the nickel thin film 3 according to Example 2 was obtained using the same method as in Example 1, but the heat treatment time was 120 minutes.
- the nickel thin film 3 according to Comparative Example 1 was obtained using the same method as in Example 1, but the heat treatment was not carried out.
- the nickel thin film 3 according to Comparative Example 2 was obtained using the same method as in Example 1, but the heat treatment was not carried out.
- the solution used as the electroplating bath had 350 g/L of nickel sulfate, 60 g/L of nickel chloride, 30 g/L of trisodium citrate dissolved therein (no surfactant contained).
- the pH of the plating bath was 4.6 and the bath temperature was 60°C.
- a nickel film with a thickness of 10 ⁇ m manufactured by rolling was prepared as the nickel thin film according to Comparative Example 3.
- a Cu film with a thickness of 10 ⁇ m manufactured by rolling was prepared as the metal film according to Comparative Example 4.
- each of the test pieces was cut to form a circle with a diameter of 20 mm. Then, the test piece was clamped and secured on the stage 11 by use of the pair of clamping members (12-1 and 12-2) which have the opening 17 and the hollow portion 16 both with a diameter of 12 mm. Further, a jig having on one end a shape corresponding to a portion of a sphere with a diameter of 7 mm was prepared as the pushing jig 14, and was attached to the pushing jig support 13. The pushing jig support 13 was moved toward the pair of clamping members 12 at a rate of 1 mm/min. Thereby, one end of the pushing jig 14 aligned with the center of the opening 17 was caused to touch the test piece. Moreover, the pushing jig 14 was pushed in until the test piece was torn, and the relationship between the displacement amount of the pushing jig 14 and the test force (force applied to the pushing jig 14) was measured with the measurement apparatus 18.
- Fig. 7 is a graph showing measurement results.
- the correspondence relationship between the curves and Examples 1 to 2 and Comparative Examples 1 to 5 is as follows:
- a portion of sudden decrease in the test force corresponds to a point at which the test piece is torn (hereinafter referred to as a breaking point) .
- a breaking point a point at which the test piece is torn.
- the nickel thin films 3 according to Examples 1 and 2 have larger displacement amounts until the test piece is broken compared to the nickel thin films and the metal films according to Comparative Examples 1 to 5. Furthermore, as compared to Comparative Examples 1 to 5, Examples 1 and 2 have a larger area of the region surrounded by the origin, the breaking point, and the point on the X-axis corresponding to the breaking point, i.e. a larger amount of work with respect to elongation. This indicates that Examples 1 and 2 have higher elongation properties, higher flexibility, and higher mechanical strengths compared to Comparative Examples 1 to 5.
- Fig. 8 is a graph showing results of calculating "flexibility values.” Note that the "flexibility values" were calculated by determining a range where the linearity is good (correlation coefficient R 2 > 0.9 in linear approximation) in the graph shown in Fig. 7 and by determining the gradient. As shown in Fig. 8 , Examples 1 and 2 have smaller “flexibility values” compared to Comparative Examples 1 and 2. To be more precise, it is understood that a nickel thin film 3 with a high elongation property and high flexibility can be obtained by carrying out electroplating with a plating bath containing a surfactant, and by removing the surfactant through heat treatment. Moreover, it is understood that the nickel thin films 3 of Examples 1 and 2 have smaller flexibility values compared to the metal films of Comparative Example 3 and 4, and have higher elongation properties and higher flexibility compared to the nickel film and the Cu film obtained by rolling.
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Abstract
Description
- The present invention relates to a porous nickel thin film and a manufacturing method thereof.
- Nickel thin films are expected to be applied to numerous fields. For example, Japanese Patent No.
4411409 - Patent Literature 1: Japanese Patent No.
4411409 - An object of the present invention is to provide a nickel thin film excellent in flexibility and a manufacturing method thereof.
- The inventors have found that a porous nickel thin film obtained by using a particular method greatly surpasses in flexibility a nickel thin film obtained by using the conventional method.
- To be more specific, the present invention includes the following aspects:
- [1] A porous nickel thin film having a flexibility value of 15.0 N/mm or less, the flexibility value being a value measured by a method including the steps of:
- supporting an entire periphery of the nickel thin film with a subject supporting jig so as to form an unsupported region with a closed shape in the nickel thin film;
- measuring a relationship between a force applied to a pushing jig and a displacement amount of the pushing jig by pushing one end of the pushing jig against the unsupported region perpendicularly to the nickel thin film; and
- obtaining a value (N/mm) by dividing the force (N) applied to the pushing jig by the displacement amount (mm) of the pushing jig, as the flexibility value.
- [2] The porous nickel thin film according to [1] described above, having a thickness of 0.1 to 100 µm.
- [3] A method for manufacturing a porous nickel thin film, including the steps of:
- forming a nickel plated film on a conductive substrate by use of a nickel electroplating bath containing a nickel salt and a surfactant; and
- heat-treating the nickel plated film so as to burn and remove the surfactant taken in the nickel plated film.
- [4] The method according to [3] described above, in which the porous nickel thin film has a flexibility value of 15.0 N/mm or less, and the flexibility value is a value measured by a method including the steps of:
- supporting an entire periphery of the nickel thin film with a subject supporting jig so as to form an unsupported region with a closed shape in the nickel thin film;
- measuring a relationship between a force applied to a pushing jig and a displacement amount of the pushing jig by pushing one end of the pushing jig against the unsupported region perpendicularly to the nickel thin film; and
- obtaining a value (N/mm) by dividing the force (N) applied to the pushing jig by the displacement amount (mm) of the pushing jig, as the flexibility value.
- [5] The method according to [3] or [4] described above, in which
the surfactant contains an anionic surfactant. - [6] The method according to [5] described above, in which
the anionic surfactant contains a compound selected from the group consisting of a polyoxyalkylene alkyl ether sulfate, a polyoxyalkylene alkyl ether carboxylate, and an alkylbenzene sulfonate. - [7] The method according to any one of [3] to [6] described above, in which
the step of forming a nickel plated film includes a step of carrying out pulse electroplating. - [8] The method according to any one of [3] to [7], in which the conductive substrate is a Ti substrate, a Cu substrate, an SUS substrate, a glass given electrical conductivity, or a resin given electrical conductivity.
- [9] The method according to any one of [3] to [8] described above, further including a step of peeling the porous nickel thin film off the conductive substrate.
- The present invention provides a nickel thin film excellent in flexibility and a manufacturing method thereof.
-
-
Fig. 1A is a cross-sectional view schematically showing a method of manufacturing a porous nickel thin film. -
Fig. 1B is a cross-sectional view schematically showing the method of manufacturing the porous nickel thin film. -
Fig. 1C is a cross-sectional view schematically showing the method of manufacturing the porous nickel thin film. -
Fig. 1D is a cross-sectional view schematically showing the method of manufacturing the porous nickel thin film. -
Fig. 2 is a view of an external appearance showing an evaluation apparatus. -
Fig. 3 is a schematic view showing the evaluation apparatus. -
Fig. 4 is a cross-sectional view schematically showing a pair of clamping members. -
Fig. 5 is a schematic view showing an example of a pushing jig. -
Fig. 6 is a schematic view showing a method of evaluating flexibility. -
Fig. 7 is a graph showing results of measuring flexibility. -
Fig. 8 is a graph showing results of calculating flexibility values. - Hereinafter, an embodiment of the present invention is described.
-
Fig. 1A to Fig. 1D are cross-sectional views schematically showing a method of manufacturing a porous nickel thin film according to the embodiment. - First, as shown in
Fig. 1A , aconductive substrate 1 is prepared. - Next, as shown in
Fig. 1B , a nickel platedfilm 2 is formed on theconductive substrate 1. - The nickel plated
film 2 is formed using a nickel electroplating bath which contains a nickel salt and a surfactant. Since the nickel electroplating bath contains a surfactant here, the nickel platedfilm 2 formed has the surfactant taken therein. - Next, as shown in
Fig. 1C , the nickel platedfilm 2 is heat-treated. Heat treatment burns and removes the surfactant taken in the nickel platedfilm 2. Then,pores 4 penetrating in the thickness direction are formed in the nickel platedfilm 2, and a porous nickelthin film 3 is obtained as a result. - In the case of using the nickel
thin film 3 as a single-layered film, the nickelthin film 3 is peeled off theconductive substrate 1 as shown inFig. 1D . In this case, to peel off the nickelthin film 3, it suffices to use in advance a substrate with low adhesion to the nickelthin film 3 as theconductive substrate 1. Such a substrate includes a metal substrate such as for example a Ti substrate, a Cu substrate, and an SUS substrate, and glass and resin material which are given electrical conductivity. Note that heat treatment for removing the surfactant may be carried out after the nickelthin film 3 is peeled off theconductive substrate 1. - On the other hand, the nickel
thin film 3 does not necessarily have to be peeled off theconductive substrate 1. Depending on the intended use, one may use a stack of theconductive substrate 1 and the nickelthin film 3 for the end use without peeling the nickelthin film 3 off theconductive substrate 1. - By use of the manufacturing method described above, it is possible to obtain the porous nickel
thin film 3 which is excellent in flexibility. To be more specific, by use of the manufacturing method described above, it is possible to obtain the porous nickelthin film 3 which has a flexibility value of 15.0 N/mm or less, preferably 10.0 N/mm or less, more preferably 1.0 to 10.0 N/mm, and still more preferably 3.0 to 8.0 N/mm. The porous nickelthin film 3 having such flexibility values is a novel metal film obtainable by the manufacturing method of the present invention, excellent in flexibility, and useful in various applications. - Note that the "flexibility value" in the present specification can be determined by the method of evaluating the porous nickel thin film and the method explained in Examples to be described later.
- In addition, the porous nickel
thin film 3 obtained in the embodiment is also excellent in thermal resistance. There is a case where the shape of a nickel thin film manufactured by e.g. rolling is not maintained because oxidation proceeds during high temperature heating. In contrast, the shape of the porous nickelthin film 3 obtained in the embodiment is maintained even during high temperature heating. - The thickness of the nickel
thin film 3 obtained in the embodiment is preferably 0.1 µm to 100 µm, more preferably 1 µm to 10 µm, and still more preferably 2 µm to 8 µm. Too large a thickness makes it difficult to form pores, raises the processing difficulty, and leads to an increase in the manufacturing cost. Conversely, too small a thickness leads to insufficient strength. - The use of the nickel
thin film 3 obtained in the embodiment is not particularly limited. For example, the nickelthin film 3 is useful as: a high performance catalytic film; a high performance filter; an undercoat for coating, painting, and plating; a functional coat and a thermal radiation coat used at high temperatures; and a surface coat for a slidable component. - In the case of use as a high performance catalytic film, the nickel
thin film 3 is used as-is, or catalytic particles such as Pt and Pd particles are scattered and held in the pores of the nickelthin film 3. In the case of use as a high performance filter, the penetration pores formed in the nickelthin film 3 are used as fluid passages. In the case of e.g. a high performance catalytic film and a high performance filter, flexibility is important in terms of the life of the coat. The nickelthin film 3 of the embodiment is preferable because it can satisfy such a requirement. - In addition, the nickel
thin film 3 obtained in the embodiment is useful as a functional coat and a thermal radiation coat which are required to have thermal resistance because it is not broken even under a high temperature atmosphere. - Moreover, the nickel
thin film 3 of the embodiment has a large surface area because it is provided with pores. For this reason, if the nickelthin film 3 is used as an undercoat for e.g. coating, painting, and plating, it is possible to increase physical adhesion between the nickelthin film 3 and a film formed thereon. - Furthermore, if the nickel
thin film 3 of the embodiment is used as a surface coat of a slidable component, it is possible to enhance lubricant retainability and to extend the life of the slidable component thanks to the pores provided. - Subsequently, detailed descriptions are provided for a nickel electroplating bath used in the embodiment and the plating conditions. As in the foregoing description, the plating bath used in the embodiment is an aqueous solution containing a nickel salt and a surfactant.
- The nickel salt acts as a supply source of nickel ions. Although the nickel salt is not particularly limited, it is preferable to use a compound selected from the group consisting of nickel sulfamate, nickel chloride, nickel sulfate, and nickel citrate. Among these, the nickel salt preferably contains nickel sulfamate. A coating with a low internal stress and high flexibility is obtained by use of nickel sulfamate.
- The concentration of the nickel salt in the plating bath is preferably 100 g/L to 800 g/L. Too high a concentration of the nickel salt reduces the saturation concentration of the surfactant, makes it difficult to form pores, and increases the possibility of losing flexibility. Too low a concentration of the nickel salt reduces the limiting current density due to insufficient concentration of the metal salt, increases the possibility of producing hydrogen gas during the formation of the coating, and increases the risk of cracks caused by the occlusion of hydrogen into the
conductive substrate 1 being the undercoat. Moreover, too low a concentration is likely to produce a rough Ni plated coating with numerous pinholes. - It is preferable to use an ionic surfactant as the surfactant contained in the plating bath. It is preferable to use an anionic surfactant as the ionic surfactant.
- Preferable examples of the anionic surfactant include a compound selected from the group consisting of a polyoxyalkylene alkyl ether sulfate, a polyoxyalkylene alkyl ether carboxylate, a polyoxyalkylene alkyl ether sulfosuccinate, a polyoxyalkylene alkyl ether phosphate, a polyoxyalkylene alkyl ether acetate, an alkylbenzene sulfonate, a higher alcohol sulfate, a polyoxyalkylene styrenated phenyl ether sulfate, an alkyl diphenyl ether sulfonate, an alpha olefin sulfonate, a dialkyl sulfosuccinate, an alkane sulfonate, a secondary alkane sulfonate, an alkyl naphthalene sulfonate, a formaldehyde condensate of a naphthalene sulfonate, a higher alcohol phosphate ester, a polyoxyalkylene styrenated phenyl ether phosphate, fatty acid soap, disproportionated rosin soap, and turkey red oil. A more preferable compound is one selected from the group consisting of the polyoxyalkylene alkyl ether sulfate, the polyoxyalkylene alkyl ether carboxylate, the polyoxyalkylene alkyl ether acetate, and the alkylbenzene sulfonate among the above.
- Note that each of the polyoxyalkylene alkyl ether sulfate and the polyoxyalkylene alkyl ether carboxylate is preferably an ethylene oxide-containing compound expressed by
Formula 1 below:
(Formula 1) : R1-O-(CH2CH2O)n-X
- Note that in
Formula 1, R1 represents an alkyl group, preferably an alkyl group having 10 to 16 carbon atoms, and more preferably an alkyl group having 12 to 14 carbon atoms. The letter X indicates a sulfate or a carboxylate. The letter n ranges from 1 to 20, preferably from 2 to 12. - In addition, the alkylbenzene sulfonate is preferably a compound having 8 to 16 carbon atoms in the alkyl group, more preferably a dodecylbenzene sulfonate.
- The counter ions used as the salt of the anionic surfactant include alkali metal salts such as a sodium salt and a potassium salt, alkali earth metal salts, ammonium salts, and alkanolamine salts. Among these, the alkali metal salts are preferable, and the sodium salt is more preferable.
- The concentration of the surfactant in the plating bath is preferably 0.1 mL/L to 100 mL/L, more preferably 1 mL/L to 50 mL/L, and still more preferably 5 mL/L to 30 mL/L. Too high a concentration of the surfactant makes it difficult to obtain a fine coating because plate deposition is hindered. On the other hand, too low a concentration makes it difficult to form pores, which makes it hard to obtain desired flexibility.
- Other additives may be added to the plating bath such as a pH adjuster, a pH buffer, and a stress releaser. Sulfuric acid, sulfamic acid, nickel hydroxide, etc. are used as the pH adjuster, for example. Saccharin etc. are used as the stress releaser, for example.
- The pH of the plating bath is preferably 2.0 to 4.5. Too high a pH reduces the limiting current density, increases the possibility of producing hydrogen gas, and increases the risk of occlusion of hydrogen into the
conductive substrate 1. Moreover, the Ni coating is likely to become hard and brittle. On the other hand, too low a pH is likely to promote decomposition of the plating bath components. - The bath temperature of the plating bath during plating is preferably 40°C to 65°C. Too high a bath temperature is likely to promote the decomposition of the bath components. On the other hand, too low a bath temperature increases the possibility of surfactant precipitation. Moreover, extraneous deposition of nickel is likely to take place.
- Although electroplating is possible using a direct current electrolysis, it is more preferable to carry out pulse electroplating. In the case of using pulse electroplating, at the early stages of deposition, it is possible to cause the surfactant to scatter and be adsorbed to the
conductive substrate 1 being the undercoat, and to promote eutectoid between the surfactant and nickel during plating. - In the case of using pulse electroplating, the average current density is preferably 1 A/dm2 to 20 A/dm2. Too high an average current density may lead to excessive production of hydrogen, affecting the
conductive substrate 1 being the undercoat. Furthermore, extraneous deposition of nickel might take place. On the other hand, too low an average current density makes it difficult to form pores, which makes it hard to obtain desired flexibility. Also, productivity is reduced. - The pulse current density is preferably 2 A/dm2 to 20 A/dm2. Too high a pulse current density may cause excessive production of hydrogen, affecting the
conductive substrate 1 being the undercoat. Furthermore, extraneous deposition of nickel might take place. On the other hand, too low a pulse current density makes it difficult to form pores, reducing productivity. - The ratio of the pulse applying time ton to the pulse pause time toff (ton/toff) is more preferably 0.1 to 10. Too large a ratio (ton/toff) makes it difficult to form pores, which makes it hard to obtain desired flexibility. Conversely, too small a ratio also makes it difficult to form pores, which makes it hard to obtain desired flexibility.
- The pulse frequency is preferably 0.1 to 1000 (Hz) . Too large a pulse frequency makes it difficult to form pores, which makes it hard to obtain desired flexibility. Conversely, too small a pulse frequency also makes it difficult to form pores, which makes it hard to obtain desired flexibility.
- Subsequently, descriptions are provided for heat treatment conditions for burning and removing the surfactant. Heat treatment is carried out under the conditions where the surfactant is burnt and removed in, for example, the atmosphere, a reducing atmosphere such as hydrogen, or an inactive atmosphere such as nitrogen or argon.
- To be more specific, the heat treatment temperature is 350°C to 900°C, for example. Besides, the heating time is 10 minutes to 120 minutes, for example. Too high a heating temperature is likely to increase the cost of mass production processing. Worse, the possibility of losing flexibility is increased because an interdiffusion layer is likely to be formed between the
conductive substrate 1 being the undercoat and the nickel platedfilm 2. On the other hand, too low a heat treatment temperature makes it difficult for porosification to occur, which makes it impossible to obtain desired flexibility. In addition, too long a heating time also increases the possibility of forming an interdiffusion layer. Conversely, too short a heating time makes it difficult for porosification to occur, increasing the possibility of losing flexibility. - As described above, the nickel
thin film 3 which is manufactured by the method according to the embodiment has a property excellent in flexibility. To be more specific, it is possible to obtain the porous nickelthin film 3 with a "flexibility value" of 15.0 N/mm or less. Here, the "flexibility value" is a value determined using an evaluation method to be described below. -
Fig. 2 is a view of an external appearance of anevaluation apparatus 10 used in the evaluation method for the flexibility value. In addition,Fig. 3 is a schematic view showing theevaluation apparatus 10. As shown inFig. 2 andFig. 3 , theevaluation apparatus 10 includes abody part 16, astage 11, a pushingjig support 13, ameasurement apparatus 18, a pushingjig 14, asubject supporting jig 12, and adrive mechanism 15. Note that the pushingjig 14 and thesubject supporting jig 12 are detachable and illustrated only inFig. 3 , not inFig. 2 . - The
stage 11 is provided to support thesubject supporting jig 12, and is supported by thebody part 16. - The
subject supporting jig 12 is provided to support the nickelthin film 3 to be tested (seeFig. 3 ). Thesubject supporting jig 12 is detachably attached to thestage 11.Fig. 4 is a cross-sectional view schematically showing thesubject supporting jig 12. Thesubject supporting jig 12 includes a pair of clamping members (12-1 and 12-2) . One clamping member 12-1 has anopening 17 provided therein. In addition, the other clamping member 12-2 has ahollow portion 16 provided at the position corresponding to theopening 17. Each of theopening 17 and thehollow portion 16 has the shape of a circle with a predetermined diameter of a. Note that the clamping member 12-2 may be provided with an opening instead of thehollow portion 16. Moreover, each clamping member (12-1 and 12-2) is provided with a screw thread (19-1 and 19-2), and it is thus possible to threadly engage the clamping member 12-1 with the clamping member 12-2 while clamping the nickelthin film 3. The center portion of the nickelthin film 3, that is, the region corresponding to theopening 17 is not in contact with thesubject supporting jig 12. That is to say, thesubject supporting jig 5 is configured to support the entire periphery of the nickelthin film 3, and an unsupported region with a closed shape corresponding to theopening 17 is formed in the center portion of the nickelthin film 3. - The pushing jig support 13 (see
Fig. 2 andFig. 3 ) is provided to support the pushingjig 14. The pushingjig support 13 is attached to thebody part 16 so as to be movable in a direction perpendicular to the nickelthin film 3. - The
drive mechanism 15 is attached to thebody part 16 and has a function of causing the pushingjig support 13 to travel. Thedrive mechanism 15 is a motor, for example. - The pushing
jig 14 has the shape of a rod. The pushingjig 14 is supported above the nickelthin film 3 by the pushingjig support 13 so as to extend in a direction perpendicular to the nickelthin film 3. In addition, one end (lower end) of the pushingjig 14 is set so as to be positioned right above the center of theopening 17 provided in the clamping member 12-1. -
Fig. 5 is a schematic view showing an example of the pushingjig 14. As shown inFig. 5 , one end of the pushingjig 14 preferably has a shape corresponding to a portion of a sphere with a predetermined diameter of b. - The measurement apparatus 18 (see
Fig. 3 ) has a function of detecting the force applied to the pushingjig 14 and the displacement amount of the pushingjig 14. To be more specific, themeasurement apparatus 18 includes a load cell 18-1 and an encoder 18-2. The load cell 18-1 is provided between the pushingjig support 13 and the pushingjig 14 and has a function of detecting the force applied to the pushingjig 14. The encoder 18-2 is connected to thedrive mechanism 15 and is configured to detect the displacement amount of the pushingjig support 13, that is, a displacement amount of the pushingjig 14. - Subsequently, a description is provided for the evaluation method of the present invention.
- First, one supports a test piece of the nickel
thin film 3 with thesubject supporting jig 12 and places thesubject supporting jig 12 on thestage 11. Also, one attaches the pushingjig 14 to the pushingjig support 13 via the load cell 18-1. - Next, the
drive mechanism 15 moves the pushingjig support 13 downwards (toward the subject supporting jig 12). This pushes one end of the pushingjig 14 aligned with the center of theopening 17 perpendicularly into the nickelthin film 3, as shown inFig. 6 . The pushingjig 14 is pushed in until the nickelthin film 3 is torn. Here, themeasurement apparatus 18 measures the force applied to the pushingjig 14 and the displacement amount of the pushingjig 14. The measurement results are stored in e.g. a computer (not shown) as data indicating the relationship between the force applied to the pushingjig 14 and the displacement amount of the pushingjig 14. - The flexibility value of the nickel
thin film 3 is determined based on the obtained data. Here, in the specification, the "flexibility value" is a value expressed by a value (N/mm) which is the force (N) applied to the pushing jig divided by the displacement amount (mm) of the pushing jig. The smaller this value, the more flexible the nickelthin film 3 is. To be more specific, the flexibility value can be calculated by creating a graph with the horizontal axis representing the displacement amount and the vertical axis representing the force (test force) applied to the pushingjig 14, and by determining the gradient within a range where the linearity is good (for example, a region where the correlation coefficient R2 determined by linear approximation is larger than 0.9). - The evaluation method described above makes it possible to properly evaluate the flexibility of the nickel
thin film 3 with a thickness of 0.1 to 100 µm. - Note that the diameter a of the
opening 17 provided in the clamping member 12-1 (seeFig. 4 ) is preferably 9 mm to 14 mm, more preferably 10 mm to 13 mm, and still more preferably 11 mm to 12 mm. Too small a diameter a makes it impossible to obtain a sufficient displacement amount for the test force, while a too large a diameter requires a large sample area. - Although not particularly limited, the shape of one end of the pushing jig 14 (see
Fig. 5 ) is preferably a shape corresponding to a portion of a sphere with a diameter of b, as already described. For example, if the shape of one end of the pushingjig 14 is a polygon, the pushingjig 14 touches the test piece at the vertexes. This increases the risk of tearing the test piece before the completion of the test because the test force concentrates at the vertexes. As a result, it becomes difficult to create a region with a high-linearity relationship in the test force-displacement amount graph. In addition, if the shape of one end of the pushingjig 14 is a flat-plate shape such as a flat plate circle, the test piece deforms to make an acute angle at an edge of this flat-plate shape. For this reason, it becomes difficult to obtain a high-linearity relationship. As opposed to the above, if the shape of one end of the pushingjig 14 has a shape corresponding to a portion of a sphere, one obtains an effect of pushing the test piece with a surface. To be more specific, when the pushingjig 14 is being pushed in, the test piece is smoothly stretched while making an obtuse angle. This helps to obtain a higher-linearity relationship. - The diameter b is preferably 5 mm to 10 mm, more preferably 6 mm to 9 mm, and still more preferably 7 mm to 8 mm. Too small a diameter b means that the test piece is pressed at a point, increasing the risk that the test piece is easily torn. On the other hand, too large a diameter b means that the
subject supporting jig 12 also needs to be large, increasing the necessary sample area. - Furthermore, the ratio of the diameter b to the diameter a of the opening 17 (diameter b/diameter a) is preferably 0.3 to 0.9, more preferably 0.4 to 0.8, and still more preferably 0.5 to 0.7. The ratio of the diameter b to the diameter a within such ranges helps to obtain a high-linearity relationship.
- The push rate of the pushing
jig 14 is preferably 0.1 mm/min to 10.0 mm/min, more preferably 0.5 mm/min to 5.0 mm/min, and still more preferably 1.0 mm/min to 2.0 mm/min. Too low a push rate requires a long time test. On the other hand, too high a push rate increases the risk of breaking the test piece, and the test piece is likely to be broken before a region with a high linearity is sufficiently obtained. - Subsequently, Examples are described for the purpose of explaining the present invention in further detail.
- An SUS substrate was prepared as the
conductive substrate 1 being the undercoat. The nickel platedfilm 2 was formed on thisconductive substrate 1 by electroplating. Here, the aqueous solution used as the electroplating bath contained 600 g/L of nickel sulfamate, 10 g/L of nickel chloride, 40 g/L of boric acid, and 10 ml/L of anionic surfactant (sodium dodecylbenzenesulfonate). The pH of the plating bath was 3.5, and the bath temperature was 60°C. The electroplating was carried out by pulse plating. Pulse plating was carried out under the conditions that the average current density was 5.9 A/dm2 and the ratio (ton/toff) was 1.4. Next, the nickel platedfilm 2 was peeled off theconductive substrate 1. Furthermore, heat treatment was carried out at 500°C on the nickel platedfilm 2 for 60 minutes in the atmosphere, and the nickelthin film 3 according to Example 1 was obtained. The thickness of the obtained nickelthin film 3 was 5 µm. - The nickel
thin film 3 according to Example 2 was obtained using the same method as in Example 1, but the heat treatment time was 120 minutes. - The nickel
thin film 3 according to Comparative Example 1 was obtained using the same method as in Example 1, but the heat treatment was not carried out. - The nickel
thin film 3 according to Comparative Example 2 was obtained using the same method as in Example 1, but the heat treatment was not carried out. Here, the solution used as the electroplating bath had 350 g/L of nickel sulfate, 60 g/L of nickel chloride, 30 g/L of trisodium citrate dissolved therein (no surfactant contained). The pH of the plating bath was 4.6 and the bath temperature was 60°C. The plating conditions included a constant current of 0.1 A. - A nickel film with a thickness of 10 µm manufactured by rolling was prepared as the nickel thin film according to Comparative Example 3.
- A Cu film with a thickness of 10 µm manufactured by rolling was prepared as the metal film according to Comparative Example 4.
- An Al film with a thickness of 10 µm manufactured by rolling was prepared as the metal film according to Comparative Example 5.
- An attempt was made to obtain the nickel thin film according to Comparative Example 6 by carrying out heat treatment on the nickel thin film according to Comparative Example 2 under the same conditions as in Example 1. However, the nickel thin film according to Comparative Example 2 after the heat treatment was brittle due to oxidation and no longer maintained its shape.
- Subsequently, evaluated were the flexibilities of the nickel thin films and the metal films obtained in Examples 1 and 2 and Comparative Examples 1 to 5. To be specific, the relationship between the test force and the displacement amount was measured by use of the
evaluation apparatus 10 described inFigs. 2 to 6 . - More specifically, each of the test pieces was cut to form a circle with a diameter of 20 mm. Then, the test piece was clamped and secured on the
stage 11 by use of the pair of clamping members (12-1 and 12-2) which have theopening 17 and thehollow portion 16 both with a diameter of 12 mm. Further, a jig having on one end a shape corresponding to a portion of a sphere with a diameter of 7 mm was prepared as the pushingjig 14, and was attached to the pushingjig support 13. The pushingjig support 13 was moved toward the pair of clampingmembers 12 at a rate of 1 mm/min. Thereby, one end of the pushingjig 14 aligned with the center of theopening 17 was caused to touch the test piece. Moreover, the pushingjig 14 was pushed in until the test piece was torn, and the relationship between the displacement amount of the pushingjig 14 and the test force (force applied to the pushing jig 14) was measured with themeasurement apparatus 18. -
Fig. 7 is a graph showing measurement results. InFig. 7 , the correspondence relationship between the curves and Examples 1 to 2 and Comparative Examples 1 to 5 is as follows: - Example 1: Curve "1"
- Example 2: Curve "2"
- Comparative Example 1: Curve "3"
- Comparative Example 2: Curve "4"
- Comparative Example 3: Curve "5"
- Comparative Example 4: Curve "6"
- Comparative Example 5: Curve "7"
- For each of the graphs in
Fig. 7 , a portion of sudden decrease in the test force corresponds to a point at which the test piece is torn (hereinafter referred to as a breaking point) . In any of Examples 1 and 2 and Comparative Examples 1 to 5, a high-linearity relationship between the displacement amount and the test force is obtained within the region from the origin to the breaking point. This indicates that the evaluation method of the present invention properly reflects the flexibility of the test piece. - As shown in
Fig. 7 , the nickelthin films 3 according to Examples 1 and 2 have larger displacement amounts until the test piece is broken compared to the nickel thin films and the metal films according to Comparative Examples 1 to 5. Furthermore, as compared to Comparative Examples 1 to 5, Examples 1 and 2 have a larger area of the region surrounded by the origin, the breaking point, and the point on the X-axis corresponding to the breaking point, i.e. a larger amount of work with respect to elongation. This indicates that Examples 1 and 2 have higher elongation properties, higher flexibility, and higher mechanical strengths compared to Comparative Examples 1 to 5. -
Fig. 8 is a graph showing results of calculating "flexibility values." Note that the "flexibility values" were calculated by determining a range where the linearity is good (correlation coefficient R2 > 0.9 in linear approximation) in the graph shown inFig. 7 and by determining the gradient. As shown inFig. 8 , Examples 1 and 2 have smaller "flexibility values" compared to Comparative Examples 1 and 2. To be more precise, it is understood that a nickelthin film 3 with a high elongation property and high flexibility can be obtained by carrying out electroplating with a plating bath containing a surfactant, and by removing the surfactant through heat treatment. Moreover, it is understood that the nickelthin films 3 of Examples 1 and 2 have smaller flexibility values compared to the metal films of Comparative Example 3 and 4, and have higher elongation properties and higher flexibility compared to the nickel film and the Cu film obtained by rolling. - Furthermore, while the flexibility values of Examples 1 and 2 are larger than that of Comparative Example 5, the test piece of Comparative Example 5 is torn at a displacement amount much smaller than those in Examples 1 and 2, as shown in
Fig. 7 . To be more specific, it is understood that the nickelthin films 3 according to Examples 1 and 2 greatly surpass in mechanical strength the Al film obtained by rolling. - What is more, while the nickel plated film according to Comparative Example 6 did not maintain its shape when heat-treated, the shapes were maintained after heat treatment and flexibility was improved as well in Examples 1 and 2. It can be said from the above description that the results of Examples 1 and 2 were unexpected.
Claims (9)
- A porous nickel thin film having a flexibility value of 15.0 N/mm or less, the flexibility value being a value measured by a method comprising the steps of:supporting an entire periphery of the nickel thin film with a subject supporting jig so as to form an unsupported region with a closed shape in the nickel thin film;measuring a relationship between a force applied to a pushing jig and a displacement amount of the pushing jig by pushing one end of the pushing jig against the unsupported region perpendicularly to the nickel thin film; andobtaining a value (N/mm) by dividing the force (N) applied to the pushing jig by the displacement amount (mm) of the pushing jig, as the flexibility value.
- The porous nickel thin film according to claim 1, having a thickness of 0.1 to 100 µm.
- A method for manufacturing a porous nickel thin film, comprising the steps of:forming a nickel plated film on a conductive substrate by use of a nickel electroplating bath containing a nickel salt and a surfactant; andheat-treating the nickel plated film so as to burn and remove the surfactant taken in the nickel plated film.
- The method according to claim 3, wherein
the porous nickel thin film has a flexibility value of 15.0 N/mm or less, and the flexibility value is a value measured by a method comprising the steps of:supporting an entire periphery of the nickel thin film with a subject supporting jig so as to form an unsupported region with a closed shape in the nickel thin film;measuring a relationship between a force applied to a pushing jig and a displacement amount of the pushing jig by pushing one end of the pushing jig against the unsupported region perpendicularly to the nickel thin film; andobtaining a value (N/mm) by dividing the force (N) applied to the pushing jig by the displacement amount (mm) of the pushing jig, as the flexibility value. - The method according to claim 3 or 4, wherein
the surfactant contains an anionic surfactant. - The method according to claim 5, wherein
the anionic surfactant contains a compound selected from the group consisting of a polyoxyalkylene alkyl ether sulfate, a polyoxyalkylene alkyl ether carboxylate, and an alkylbenzene sulfonate. - The method according to any one of claims 3 to 6, wherein
the step of forming a nickel plated film includes a step of carrying out pulse electroplating. - The method according to any one of claims 3 to 7, wherein
the conductive substrate is a Ti substrate, a Cu substrate, an SUS substrate, a glass given electrical conductivity, or a resin given electrical conductivity. - The method according to any one of claims 3 to 8, further comprising a step of peeling the porous nickel thin film off the conductive substrate.
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JP2001085015A (en) * | 1999-09-17 | 2001-03-30 | Sumitomo Metal Steel Products Inc | Porous nickel foil for alkaline storage battery negative electrode and manufacture therefor |
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JP5487487B2 (en) * | 2010-08-20 | 2014-05-07 | 富山住友電工株式会社 | Metal porous body and method for producing the same |
JP5635382B2 (en) * | 2010-12-08 | 2014-12-03 | 住友電気工業株式会社 | Method for producing porous metal body having high corrosion resistance |
JP2013014819A (en) * | 2011-07-06 | 2013-01-24 | Murata Mfg Co Ltd | Porous metal film, electrode, current collector, electrochemical sensor, power storage device and sliding member as well as method for producing porous metal film |
JP6212869B2 (en) * | 2012-02-06 | 2017-10-18 | 三菱マテリアル株式会社 | Oxide sputtering target |
JP6047711B2 (en) * | 2012-02-08 | 2016-12-21 | 石原ケミカル株式会社 | Electroless nickel and nickel alloy plating method, and pretreatment liquid for the plating |
CN103243357B (en) * | 2013-05-13 | 2015-09-23 | 重庆大学 | The preparation method of three-dimensional porous nickel film |
CN107849724A (en) * | 2014-10-29 | 2018-03-27 | 林科闯 | Porous material and system and its manufacture method |
JP6056023B2 (en) * | 2014-11-05 | 2017-01-11 | 株式会社山王 | Metal composite hydrogen permeable membrane and manufacturing method thereof |
JP6014920B1 (en) * | 2015-08-19 | 2016-10-26 | 株式会社山王 | Metal composite hydrogen permeable membrane and manufacturing method thereof |
-
2015
- 2015-11-06 JP JP2015218685A patent/JP6319771B2/en active Active
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2016
- 2016-11-02 WO PCT/JP2016/082608 patent/WO2017078069A1/en active Application Filing
- 2016-11-02 CN CN201680029173.3A patent/CN107614756A/en active Pending
- 2016-11-02 US US15/575,236 patent/US20180230615A1/en not_active Abandoned
- 2016-11-02 EP EP16862129.0A patent/EP3296432A4/en not_active Withdrawn
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CN107614756A (en) | 2018-01-19 |
JP6319771B2 (en) | 2018-05-09 |
US20180230615A1 (en) | 2018-08-16 |
TWI617672B (en) | 2018-03-11 |
JP2017088940A (en) | 2017-05-25 |
TW201718896A (en) | 2017-06-01 |
EP3296432A4 (en) | 2018-12-19 |
WO2017078069A1 (en) | 2017-05-11 |
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