TWI431170B - A glossy nickel plating material, an electronic component using a glossy nickel plating material, and a method of manufacturing a glossy nickel plating material - Google Patents

Description

Gloss nickel plating material, electronic component using gloss nickel plating material, and manufacturing method of glossy nickel plating material

The present invention relates to a glossy nickel plating material, an electronic component using a glossy nickel plating material, and a method of producing a glossy nickel plating material.

A material having glossy nickel plating is used on a metal substrate such as an electronic component such as a terminal or a connector or a metal ornament. The problem that arises when manufacturing glossy nickel plating is that the appearance of the plating is affected by the surface characteristics of the plating material. For example, when performing gloss nickel plating on a strip of brass (Cu-30%Zn), if the brass material is a blunt material, there is no good gloss on the appearance after plating, and sometimes it may appear similar. Blur or the appearance of a mixture of luster and blur. Further, when gloss nickel plating was performed on a strip of phosphor bronze (Cu-8% Sn-P), it was confirmed that the same problem occurred.

In order to solve such a problem, for example, Patent Document 1 discloses a method of producing a copper alloy having excellent electroplating properties. It is described that if the technical features are utilized, the thickness of the work-affected layer on the surface of the copper alloy can be reduced, and in particular, good electroplated silver or electroplated copper can be formed.

[Previous Technical Literature]

[Patent Document 1] JP-A-2007-39804

However, although the copper alloy described above is well suited for electroplating silver or electroplated copper, it is difficult to obtain a good gloss on glossy nickel plating, and there is still much room for improvement. Therefore, an object of the present invention is to provide a glossy nickel plating material having a good appearance, an electronic component using a glossy nickel plating material, and a method of producing a glossy nickel plating material.

As a result of careful review, the present inventors have obtained a gloss nickel plating having a good appearance by forming a work-affected layer on the surface of a metal substrate having a plating treatment. The fact opposite to Patent Document 1 is found.

The present invention, which is based on the above knowledge, is a glossy nickel plating material in the present embodiment, comprising: a metal substrate having a surface-treated metamorphic layer having a thickness of 0.2 μm or more; and a nickel plating layer formed on the metal On the surface of the substrate.

Further, in another embodiment, the gloss nickel plating material of the present invention has a thickness of the processed deterioration layer of 0.25 to 3.0 μm.

Further, in another embodiment, the gloss nickel plating material of the present invention has a thickness of the processed deterioration layer of 0.3 to 2.0 μm.

In the gloss nickel plating material of the present invention, in another embodiment, the nickel crystal particles constituting the nickel plating layer have a diameter of less than 0.3 μm.

Further, in another embodiment, the nickel electroplated material of the present invention has a nickel crystal particle diameter of 0.01 to 0.3 μm.

In another embodiment of the glossy nickel plating material of the present invention, the metal substrate is formed of stainless steel, copper or a copper alloy.

In another embodiment of the invention, an electronic component of a glossy nickel plating material is used.

According to still another embodiment of the present invention, in a method for producing a gloss nickel plating material, a metal substrate having a surface-treated altered layer thickness of 0.2 μm or more is prepared, and a nickel plating layer is formed on the surface.

In one embodiment of the method for producing a glossy nickel plating material of the present invention, the nickel crystal particles constituting the nickel plating layer have a diameter of less than 0.01 to 0.3 μm.

According to the present invention, it is possible to provide a glossy nickel plating material having a good appearance, an electronic component using a glossy nickel plating material, and a method of producing a glossy nickel plating material.

(metal substrate)

Although not limited to the type of the metal substrate of the present invention, for example, stainless steel, copper or a copper alloy may be mentioned. Among them, materials such as martensite, ferrite, and austenite can be used as the stainless steel. In addition, although a base material for an electronic component such as a connector or a terminal is used as a copper or a copper alloy, any copper or copper alloy may be used. However, it is preferable to use a connection terminal for electric or electronic equipment. The system uses a higher electrical conductivity (such as IACS (International Annealed Copper Standard: the value of the international standard soft copper conductivity of 100) is 15 to 80%), such as Cu-Sn-P (such as phosphor bronze) , Cu-Zn (such as brass, copper), Cu-Ni-Zn (such as white), Cu-Ni-Si (copper-nickel-silicon alloy), Cu-Fe-P alloy. Further, the shape of the metal substrate is not particularly limited, and it may be a plate shape, a strip shape, or a compressed product.

On the surface of the metal substrate on which the nickel plating layer is applied, the work-affected layer has a thickness of 0.2 μm or more. If the affected layer is less than 0.2 μm, all the structures or portions of the nickel plating formed on the surface become coarse, and a good appearance plating cannot be obtained. The so-called work-affected layer is a fine layer of crystal grains which is produced on the surface of the metal by press processing or polishing wheel polishing. The thickness of the work-affected layer is preferably 0.25 to 3.0 μm, more preferably 0.3 to 2.0 μm.

In addition, in the production of a glossy nickel plating material, although a plating resist is formed by plating on a metal substrate using a gloss agent, as described above, depending on the state of the surface of the metal substrate, sometimes the appearance of nickel plating is not very glossy. . That is because nickel plating has characteristics that are easily affected by metal crystallization of the substrate. For example, when the crystal grains of the metal substrate are coarse, the crystal grains to be plated are also increased, and as a result, the unevenness of the plating surface is also increased. Therefore, the appearance of the plating becomes dull. Further, when the crystal grains of the metal substrate are fine and the plating structure is fine, the plating surface becomes smooth. Therefore, the appearance of plating becomes gloss.

(Gloss nickel plating)

The glossy nickel plating material of the present invention is formed by forming a nickel plating layer on the surface of the processed metal substrate. This nickel plating layer is composed of a crystal grain diameter (less than 0.3 μm) having a metal crystal grain size corresponding to the surface of the metal substrate. This nickel plating layer has a good luster as described above because the crystal grain diameter is fine. Further, the crystal grains constituting the nickel plating layer preferably have a crystal grain diameter of 0.01 to 0.3 μm.

Although the nickel plating layer is made of nickel, it also contains a very small amount of organic luster component. This is because the gloss component is slightly infiltrated into the protective film during the plating step.

Further, the electronic component such as the terminal or the connector of the present invention is composed of the above-mentioned glossy nickel plating material.

(Manufacturing method of gloss nickel plating material)

First, a metal substrate formed of stainless steel, copper or a copper alloy or the like is prepared. Next, a work-affected layer is formed on the surface of the metal substrate by, for example, rolling, skinpass rolling, polishing wheel grinding, and brush grinding. The processing conditions are, for example, adjusting the degree of press working, and the pressure or time during polishing of the polishing wheel is such that the thickness of the processed metamorphic layer is 0.2 μm or more. The observation layer for processing the metamorphic layer is subjected to cross-sectional observation using FIB (Focused Ion Beam) to confirm the success of the processing.

Next, prepare a gloss nickel plating bath. A glossy nickel plating bath for a glossy nickel plating bath with a water soluble nickel salt, a pH buffer, and a gloss.

Here, examples of the water-soluble nickel salt include nickel sulfate, nickel chloride, and the like, and the addition thereof is 250 to 350 g/L in total.

The pH buffer may, for example, be boric acid, citric acid or the like, and these additions are 35 to 45 g/L in total.

As the glossing agent, for example, saccharin, 1,4-butynediol, and the like are added in a total amount of 0.1 to 2 g/L.

The gloss nickel plating solution is an aqueous solution, and the pH is preferably adjusted to 3 to 5, preferably to 3.8 to 4.2.

Further, the gloss nickel plating solution is preferably used at a bath temperature of 40 to 60 ° C, more preferably 45 to 50 ° C.

If the pH of the gloss nickel plating solution and the bath temperature are out of the above range, there is a problem that the plating speed is slow or the appearance is poor.

Next, the surface-processed metal substrate is immersed in a gloss plating bath for a predetermined period of time to obtain a glossy gloss nickel plating substrate. At this time, the diameter of the crystal particles is preferably less than 1 μm on the surface of the metal substrate, and since a work-affected layer having a thickness of 0.01 to 0.2 μm is formed, the diameter of the metal crystal particles of the plating layer formed on the surface also becomes More detailed. Therefore, the surface of the formed plating layer is also smoother and a good gloss can be obtained.

[Examples]

The following are examples of the invention, but are provided to provide a better understanding of the invention and are not intended to limit the invention.

(Example 1: Examples 1 to 10)

A brass plate having a thickness of 0.65 mm was prepared as a metal substrate. The surface of the brass plate was ground by a polishing wheel to form a work-affected layer having a thickness as shown in Table 1. The thickness of this metamorphic layer is viewed using FIB.

Further, the diameter of the metal crystal particles constituting the work-affected layer of the metal substrate was observed by FIB.

Next, a gloss plating bath containing the gloss plating solution of the following components was prepared.

NiSO ₄ ‧6H ₂ O 250g/l

NiCl ₂ ‧6H ₂ O 50g/l

Boric acid 40 saccharin 2g/l

1-4 butynediol 0.2g/l

Next, the surface-processed brass plate was degreased, pickled, and then immersed in an electroplating bath to form a plating layer at a current density of 5 A/dm ² . The gloss plating bath was set to a pH of 4.0 and a temperature of 45 °C.

Fig. 1 is an enlarged cross-sectional view showing a brass base material and a modified graded nickel plating layer of Example 3.

(Example 2: Comparative Examples 1 to 5)

In Comparative Examples 1 to 5, first, a copper foil similar to that of the Example was prepared. Next, the same plating bath as in the embodiment was prepared, and the surface of the brass plate was not processed, or the plating was lightly performed by light processing such as brush polishing. The plating current and bath temperature were also set to be the same as in the examples.

(assessment)

The FIB was used to observe the profile of the diameter of the nickel crystal particles constituting the nickel plating layer.

The appearance of the nickel plating layer was observed. The appearance was evaluated using a gloss meter (Nippon Denshoku Industrial Reflectance Meter ND-1). If the measured value exceeds 1.8, the evaluation is ○. If the measured value is between 1.6 and 1.8, the evaluation is △, if the measured value is low. It is evaluated as × at 1.6.

Table 1 shows the results of Example 1 and Example 2.

Fig. 1 is an enlarged cross-sectional view showing a brass base material, a work-affected layer and a nickel plated layer of Example 3.

Claims (9)

A glossy nickel plating material comprising: a metal substrate having a surface-treated metamorphic layer having a thickness of 0.2 μm or more; and a nickel plating layer formed on a surface of the metal substrate. The glossy nickel electroplating material according to claim 1, wherein the processed metamorphic layer has a thickness of 0.25 to 3.0 μm. The glossy nickel electroplating material according to claim 2, wherein the processed metamorphic layer has a thickness of 0.3 to 2.0 μm. The gloss nickel plating material according to any one of claims 1 to 3, wherein the nickel crystal particles constituting the nickel plating layer have a diameter of less than 0.3 μm. The gloss nickel plating material according to claim 4, wherein the nickel crystal particles constituting the nickel plating layer have a diameter of 0.01 to 0.3 μm. The gloss nickel plating material according to any one of claims 1 to 3, wherein the metal substrate is formed of stainless steel, copper or a copper alloy. An electronic component using the glossy nickel plating material according to any one of claims 1 to 3. A method for producing a glossy nickel plating material, wherein a metal substrate having a thickness of a surface-treated metamorphic layer of 0.2 μm or more is prepared, and a nickel plating layer is formed on the surface. The method for producing a glossy nickel plating material according to claim 8, wherein the nickel crystal particles constituting the nickel plating layer have a diameter of 0.01 to 0.3 μm.