JP2945819B2 - Platinum plating method and jig for platinum plating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a platinum plating method and a jig for platinum plating.

[0002]

2. Description of the Related Art In a conventional platinum plating method, an object 3 to be plated is gripped by upper and lower claws 2 of a jig 1 for platinum plating shown in FIG. 5 and then put into a pretreatment tank 4 as shown in FIG. To perform a pre-treatment by a chemical etching method, and thereafter, the object to be plated 3 is immersed in a platinum plating tank 5 as shown in FIG.
Then, a current is supplied from the upper and lower claws 2 to perform platinum plating.

In such a platinum plating method, platinum may not adhere to the vicinity of the workpiece 3 gripped by the upper and lower claws 2 or platinum may be deposited but the plating thickness may be reduced. In this case, this tendency was remarkable. It was thought that this phenomenon was caused by current intensively flowing in the upper and lower claws 2 of the jig 1 for platinum plating, but it was not clear.

Accordingly, the present inventors have developed a jig 1 for platinum plating.
Investigation of the phenomenon of non-plating near the area gripped by the upper and lower claws 2 revealed that the concentration of the pretreatment liquid (F system) became more remarkable as the concentration became thinner. It was found that, when 1% was broken, the area gripped by the nail 2 became thin with a radius of about 3 mm, and that platinum did not adhere. Also, as a phenomenon during the pretreatment, the hydrogen generation status of the object to be plated (titanium) 3 and the nail 2 (platinum is deposited on titanium by repeated use) 2 are different.
Hydrogen is generated intensively from the part, and as a result, a potential difference is generated between the plating object 3 and the nail 2, the nail 2 side becomes a positive electrode, a local battery action occurs, and the pretreatment liquid acts. I found that it became difficult.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made based on the above findings, and it has been found that platinum does not adhere near the upper and lower claws of an object to be plated, or that the thickness of the platinum plating is reduced. An object of the present invention is to provide a platinum plating method and a jig for platinum plating that can prevent the occurrence of unevenness.

[0006]

According to the present invention, there is provided a platinum plating method for solving the above-mentioned problems, in which an object to be plated is gripped by upper and lower claws of a platinum plating jig insulated and covered by a chemical etching method. Perform pre-treatment, and then grip the object to be plated with the upper and lower claws of the platinum plating jig that do not have insulation coating, immerse it in the platinum plating tank, and apply electricity from the upper and lower claws that do not insulate the plating object. And performing platinum plating.

Further, a platinum plating jig used for carrying out the platinum plating method of the present invention comprises a rack provided with hanging hooks above the upper end, a claw coated with an insulating coating and a claw having an insulating coating. It is provided symmetrically with a grip portion integrally having a claw without insulation coating.

[0008]

As described above, in the platinum plating method of the present invention, the object to be plated is gripped by the upper and lower claws of the platinum plating jig which are insulated and coated, and the pretreatment is performed by the chemical etching method.
The local battery action does not occur on the upper nail where no platinum is deposited, and the pretreatment liquid sufficiently activates and activates near the grip of the object to be plated. Therefore, after the pretreatment, the object to be plated is gripped by the upper and lower claws of the jig for platinum plating without insulation coating, immersed in a platinum plating tank, and energized from the upper and lower claws without insulation coating on the object to be plated. By performing platinum plating, platinum adheres at a certain thickness to the area to be gripped by the upper and lower claws of the object to be plated, and the platinum plating thickness of the entire object to be plated becomes uniform and uniform. . Further, according to the jig for platinum plating of the present invention, the above-mentioned platinum plating method can be easily and reliably performed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the platinum plating method and platinum plating jig of the present invention will be described. First, jig for platinum plating
The jig for platinum plating 1 ′ comprises a claw 9 provided with an insulating coating 8 and a claw 10 not provided with an insulating coating on the top and the bottom of a rack 7 having a hanging hook 6 above the upper end. And a symmetrically provided gripping portion 11 having the same.

Next, the platinum plating method of the present invention using the platinum plating jig 1 'having the above structure will be described with reference to the drawings. As shown in FIG.
A 100 mm, 100 mm high titanium plate 12 is coated with a claw 9 with insulating coating 8 on upper and lower grips 11 of a platinum plating jig 1 ′.
And 5% NH ₄ HF ₂ , 30% H ₂ SO as shown in FIG.
₄ (containing 0.25% NH ₄ HF ₂ ), 0.1% NH ₄ HF ₂ , and 5% H ₂ SO ₄ were immersed in a tank 14 containing a pretreatment liquid 13 to pretreat the titanium plate 12. At this time, no potential difference was generated between the titanium plate 12 and the nail 9, no local battery action occurred, and each pretreatment liquid sufficiently acted on the vicinity of the gripping of each titanium plate 12 to activate. Thereafter, the jig 1 'for platinum plating was pulled up from the pretreatment liquid 13 in each tank 14, the titanium plate 12 was removed from the upper and lower claws 9 provided with the insulating coating 8, and the upper and lower claws 10 without the insulating coating were gripped by the upper and lower claws 10. As shown in FIG.
A current was applied from the upper and lower claws 10 which were not coated with an insulating material to perform platinum plating.

When the titanium plate 12 thus plated with platinum was inspected, platinum was adhered at a thickness of 0.8 μm also in the vicinity where the titanium plate 12 and the upper and lower claws 10 were gripped.
The entire platinum plating thickness was uniform without unevenness.

[0012]

As described above, according to the platinum plating method of the present invention, platinum can be reliably adhered at a constant thickness also in the vicinity of the object to be plated, which is gripped by the upper and lower claws. The plating thickness can be made uniform without unevenness. Further, according to the jig for platinum plating of the present invention, the platinum plating method having the above-mentioned excellent effects can be easily and reliably performed.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a jig for platinum plating of the present invention.

FIG. 2 is a diagram showing the steps of one embodiment of the platinum plating method of the present invention.

FIG. 3 is a diagram showing the steps of one embodiment of the platinum plating method of the present invention.

FIG. 4 is a diagram showing the steps of one embodiment of the platinum plating method of the present invention.

FIG. 5 is a diagram showing steps of a conventional platinum plating method.

FIG. 6 is a diagram showing steps of a conventional platinum plating method.

FIG. 7 is a diagram showing steps of a conventional platinum plating method.

[Explanation of symbols]

 1 'Platinum plating jig 6 Hanging hook 7 Rack 8 Insulation coating 9 Insulation coating nail 10 Non-insulation coating nail 11 Gripping part 12 Titanium plate (plated material) 13 Pretreatment liquid 14 Tank 15 Platinum plating tank

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C25D 17/08 C25D 17/06 C25D 5/38

Claims (2)

(57) [Claims] An object to be plated is gripped by upper and lower claws of a platinum plating jig insulated and coated, and pre-treated by a chemical etching method. A platinum plating method, wherein the platinum plating is carried out by gripping the upper and lower claws with no insulation coating, immersing them in a platinum plating tank, and applying electricity to the plating object from the upper and lower claws without insulation coating. 2. A platinum symmetrically provided with a grip portion integrally having an insulated claws and a non-insulated claws at the top and bottom of a rack having hanging hooks above the upper end. Jig for plating.