JP2022032328A - Blackened film for decorative and target - Google Patents

Abstract

To provide a blackened film for decoration of a novel composition, free of carbides, applicable to a variety of uses or a novel use of the blackened film.SOLUTION: A blackened film for decoration has a composition composed of a nitride represented by (Al1-x-yCrxBy)1-zNz, where x denotes an atomic ratio of Cr to the total of Al, Cr and B, y denotes an atomic ratio of B to the total of Al, Cr, and B, z denotes an atomic ratio of N to the total of Al, Cr, B and N, with 0.05≤x≤0.15, 0.05≤y≤0.15, and 0.50≤z≤0.65, the blackened film having a thickness of 2.0-3.5 μm.SELECTED DRAWING: None

Description

The present invention relates to a decorative blackening film and a target used to form the decorative blackening film.

In the field of consumer products such as eyeglass frames and watch bands, a black appearance may be required for the purpose of enhancing the design. As a method for forming a black film (blackening film) on the surface of a product, several methods using a physical vapor deposition method (PVD) such as ion plating and sputtering have been proposed.

For example, Patent Document 1 discloses that a product surface is coated with carbon liberated from the target by sputtering using a graphite target.
Further, Patent Document 2 discloses that silicon is evaporated and ionized by ion plating and acetylene as a reaction gas is introduced to form a black silicon carbide-based film on the surface of the object to be treated. There is.

Japanese Unexamined Patent Publication No. 2-80555 Japanese Unexamined Patent Publication No. 4-41663

The blackened film disclosed in the above patent document has problems such as poor heat resistance because it uses graphite or carbide, and when considering various uses or new uses of the blackened film, the composition is different from the conventional one. Blackened film is required.
Against the background of the above circumstances, the present invention provides a decorative blackening film having a novel composition without using carbides, aims to enrich the technology related to the decorative blackening film, and for such decoration. It was made for the purpose of providing a target for forming a blackened film.

As a result of diligent studies to solve the above problems, the present inventors have added a black color by thickening the nitride of the Al alloy containing a predetermined amount of Cr and B to 2.0 μm or more. I found it possible. The present invention has been made based on such findings.
The decorative blackening film of the present invention is a blackening film formed on the base material and decorating the surface of the base material, and has a composition of (Al _1-xy Cr _x By) _{1-z N.} It consists of a nitride represented by _z , where x indicates the atomic ratio of Cr to the total of Al, Cr and B, and y indicates the atomic ratio of B to the total of Al, Cr and B. Indicates the atomic ratio of N to the sum of Al, Cr, B and N, with 0.05 ≦ x ≦ 0.15, 0.05 ≦ y ≦ 0.15, 0.50 ≦ z ≦ 0.65. It is characterized by having a film thickness of 2.0 to 3.5 μm.
According to the decorative blackening film of the present invention thus defined, it is possible to obtain a black film having a low reflectance under a novel composition that does not use carbides.

Further, the target of the present invention is a target used for forming the decorative blackening film and has a composition represented by Al _1-xy Cr _x By, where _x is Al, Cr and B. The atomic ratio of Cr to the total is shown, and y indicates the atomic ratio of B to the total of Al, Cr, and B, which is 0.05 ≦ x ≦ 0.15 and 0.05 ≦ y ≦ 0.15. It is characterized by that.
According to the target of the present invention defined in this way, the decorative blackened film can be formed by reactive sputtering using a normal sputtering device.

Next, an embodiment of the present invention will be specifically described.
<1. Blackening film for decoration ＞
The decorative blackening film of the present embodiment (hereinafter, may be simply referred to as a blackening film) is a blackening film formed on a base material and decorating the surface of the base material, and has a composition (Al _1-xy Cr _x) . By) It is a nitride represented by _{1-z N z} .
Here, x indicates the atomic ratio of Cr to the total of Al, Cr, and B, y indicates the atomic ratio of B to the total of Al, Cr, and B, and z indicates the total of Al, Cr, B, and N. The atomic ratio of N to is shown. In this example, these x, y, and z are defined as 0.05 ≦ x ≦ 0.15, 0.05 ≦ y ≦ 0.15, and 0.50 ≦ z ≦ 0.65, respectively.

Next, the reasons for limiting each chemical component in the blackened film will be described below.
Cr amount (x): 0.05 ≦ x ≦ 0.15
B amount (y): 0.05 ≦ y ≦ 0.15
The nitride of Al is generally white, but the color of the nitride can be blackened by containing Cr and B together with Al as a metal component. The color tone of the film can be evaluated by the reflectance, where the amount of Cr (x) and the amount of B (y) in the metal component are determined in this example, where black is formed when the reflectance is small and white is formed when the reflectance is large. It is defined as 0.05 ≦ x ≦ 0.15 and 0.05 ≦ y ≦ 0.15, respectively, in which a high reflectance reduction effect can be obtained.
The more preferable Cr amount (x) is 0.08 ≦ x ≦ 0.12, and the B amount (y) is 0.08 ≦ y ≦ 0.12.

N amount (z): 0.50 ≤ z ≤ 0.65
The effect of reducing the reflectance also depends on the amount of N, which is a non-metal component. In this example, the amount of N (z) is set to 0.50 or more so that the reflectance reducing effect can be obtained. The upper limit of the amount of N (z) is 0.65 in consideration of manufacturability. A more preferable amount of N (z) is 0.60 ≦ z ≦ 0.65.

The base material on which the blackening film of the present embodiment is formed is not particularly limited, but a steel material such as stainless steel can be exemplified. By applying hairline processing, vibration processing, blasting, or the like to the surface of the base material to provide irregularities on the surface of the base material, the adhesion between the blackened film and the surface of the base material can be enhanced.

The blackened film is not limited to the one formed on the entire surface of the base material, and may be partially formed, but the thickness of the blackened film is 2.0 to 3.5 μm. If the blackened film is excessively thin, color unevenness (gradient pattern) may occur due to interference between the light reflected on the surface of the blackened film and the light transmitted through the blackened film and reflected on the surface of the substrate. Therefore, the thickness of the blackened film is set to 2.0 μm or more. On the other hand, if the blackened film is excessively thick, the adhesion to the substrate is lowered, so in this example, the upper limit of the film thickness is 3.5 μm.

A reactive sputtering method containing nitrogen gas can be preferably used for forming the blackened film. Specific examples thereof include a balanced magnetron sputtering method, an unbalanced magnetron sputtering method, and an ion plating method. The composition of the metal component of the blackening film formed by sputtering is almost the same as the composition of the sputtering target, and the film formation by sputtering is also excellent in manufacturability. The blackened film formed on the surface of the base material may contain unavoidable impurities in addition to Al, Cr, B, and N.

<2. Target ＞
The target of the present embodiment is used for the purpose of forming a blackening film for decoration, contains Al, Cr, and B, and has a composition represented by Al _1-xy Cr _x By ₍ unavoidable). May contain target impurities).
Here, x indicates the atomic ratio of Cr to the total of Al, Cr, and B, and y indicates the atomic ratio of B to the total of Al, Cr, and B. In this example, these x and y are defined as 0.05 ≦ x ≦ 0.15 and 0.05 ≦ y ≦ 0.15, respectively. The reason why these x and y are defined in the same range as in the case of the blackened film is that the composition of the metal component of the blackened film formed by the sputtering method is almost the same as the composition of the sputtering target. ..

The target can be produced by mixing a powder containing a component element and pressurizing the mixed powder from cold to hot. The raw material powder may be a pure metal or an alloy containing a component element. Examples of the molding method include a cold hydrostatic pressure forming (CIP) method, a hot hydrostatic pressure forming (HIP) method, a hot extrusion method, and an ultra-high pressure hot pressing method.
Further, in some cases, it is also possible to manufacture a block of steel having a predetermined composition by melting and cut it out to prepare a target.

Next, examples of the present invention will be described in detail below. In this example, as shown in Table 1 below, the composition of the blackened film represented by (Al _1-xy Cr _x By) _{1-z Nz and} the film thickness of the blackened film were changed. Various test pieces were manufactured, and the reflectance and adhesion of these test pieces were evaluated.

<Preparation of test piece>
The powders of each element (Al, Cr, B) are mixed and sintered so as to have the metal component composition shown in Table 1 above, and the obtained sintered body is machined to obtain Cr amount (x) and B amount ( Five kinds of targets having y) of 0.02, 0.05, 0.10, 0.15, and 0.20 were prepared.
Next, a blackened film having a predetermined thickness was formed on the surface of the base material for evaluation by a reactive sputtering method using the prepared target.
The specifications of the base material used are as follows.
-Material: SUS304, Size: 100 mm x 100 mm x 1 mm, Surface finish: Vibration processing

The film forming conditions by sputtering are as follows.
・ Vacuum degree: 5 × 10 ^-4 Pa or less ・ Formation gas: Mixed gas of Ar gas and nitrogen gas ・ Flow rate ratio of nitrogen gas: 50% or more ・ Spatter pressure: 0.67 Pa
・ Spatter power: 500W

<Evaluation of reflectance>
Using the test piece prepared as described above, the reflectance was measured according to JIS K 7105. Specifically, the reflectance of visible light (wavelength 400 to 800 nm) at each wavelength of 50 nm was measured using an ultraviolet-visible spectrophotometer, and the average value was calculated as the reflectance. The reflectance was measured by measuring the reflected light when the substrate side was viewed from the blackened film side, that is, the reflected light when the light was incident on the substrate side from the blackened film side. The target reflectance is 10% or less.

<Evaluation of adhesion>
The adhesion between the blackened film and the substrate was evaluated according to JIS K5600-5-6. The target is classification 0 where adhesion is defined by JIS K5600-5-6. If it was not classified as 0, it was rejected.

Table 1 shows the evaluation results for reflectance and adhesion. The following can be seen from the results in Table 1.

Comparative Examples 1 to 3 are examples in which the composition of the blackened film (each amount of Al, Cr, B, and N) is within the specification of the present invention, but the film thickness is out of the specification of the present invention. Comparative Examples 1 and 2 having a film thickness of less than the lower limit of 2.0 μm of the present invention have good adhesion, but the target inhibitory effect (reflectance of 10% or less) has not been obtained for the reflectance. ..
On the other hand, in Comparative Example 3 in which the film thickness exceeds the upper limit of 3.5 μm of the present invention, the reflectance suppressing effect is high, but the target adhesion (classification 0) is not obtained.

Comparative Examples 4 to 6 are examples in which the amount of N in the blackened film is as high as 0.65 as compared with Comparative Examples 1 to 3. In Comparative Examples 4 and 5 in which the film thickness is less than the lower limit of 2.0 μm of the present invention, the target reflectance suppressing effect is not obtained. On the other hand, in Comparative Example 6 in which the film thickness exceeds the upper limit of 3.5 μm of the present invention, the target adhesion (classification 0) is not obtained. That is, the result is the same as in the cases of Comparative Examples 1 to 3.

Comparative Example 7 is an example in which the amount of Cr (x) and the amount of B (y) are as high as 0.15 as compared with Comparative Example 3. On the other hand, Comparative Example 8 is an example in which the amount of Cr (x) and the amount of B (y) are as low as 0.05 as compared with Comparative Example 3. In each of these Comparative Examples 7 and 8, the film thickness exceeds the upper limit of 3.5 μm of the present invention, and the reflectance suppressing effect is high, but the target adhesion (classification 0) is not obtained. If the blackened film is excessively thick, it is presumed that the internal stress of the film becomes high, peeling occurs, and the adhesion deteriorates.

Comparative Examples 9 to 11 are examples in which the amount of Cr (x) and the amount of B (y) are both 0.02, which is lower than the lower limit of the present invention. In such a case, the target reflectance suppressing effect cannot be obtained regardless of whether the film thickness is 2.0 μm, 3.0 μm, or 4.0 μm.

Comparative Examples 12 to 14 are examples in which both the Cr amount (x) and the B amount (y) are 0.20, which exceeds the upper limit of the present invention. Even in such a case, the target reflectance suppressing effect cannot be obtained as in the cases of Comparative Examples 9 to 11. That is, if Cr and B are too much or too little, the film does not turn black (reflectance cannot be suppressed low).
As described above, there is no comparative example in which the targets for both the adhesion and the reflectance are achieved.

On the other hand, in Examples 1 to 8 provided with the blackening film satisfying the provisions of the present invention, good results were obtained in both adhesion and reflectance.
Based on the above results, it is possible to reduce the reflectance to 10% or less by setting the film thickness to 2 μm or more in the Al alloy nitride film containing a predetermined amount of Cr and B. I understand. Further, when the adhesion is taken into consideration, it can be seen that it is preferable to set the film thickness of the blackened film to 2.0 to 3.5 μm.

The embodiments and examples of the present invention have been described in detail above, but this is merely an example. The present invention can be carried out in a mode in which various modifications are made without departing from the spirit of the present invention.

Claims (2)

A blackening film formed on a base material and decorating the surface of the base material.
The composition consists of a nitride represented by (Al _1-xy Cr _x By) _1-z N _z , where x indicates the atomic ratio of Cr to the sum of Al, Cr and B, and _y is Al. The atomic ratio of B to the sum of Cr and B is shown, and z indicates the atomic ratio of N to the sum of Al, Cr, B and N.
0.05 ≤ x ≤ 0.15,
0.05 ≤ y ≤ 0.15,
With 0.50 ≤ z ≤ 0.65,
A decorative blackening film characterized by a film thickness of 2.0 to 3.5 μm. A target used for forming the decorative blackening film according to claim 1.
It has a composition represented by Al _1-xy Cr _x By, where x indicates the atomic ratio of Cr to the sum of Al, Cr and B, and _y is the atomic ratio of B to the sum of Al, Cr and B. Shows the atomic ratio,
0.05 ≤ x ≤ 0.15,
0.05 ≤ y ≤ 0.15,
A target characterized by being.