JP2009287084A - Composite material and ornament - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, in the method where management is performed in such a manner that reflectance in a visible light region is made maximum in a red wavelength region or is made minimum in a blue wavelength region, since the maximum/minimum value tends to shift from a target wavelength by the variation of production conditions, there is a failure that color tones are hard to stabilize. <P>SOLUTION: The composite material includes: one or more first phases essentially consisting of Pt; and one or more second phases containing Cu, also, the reflectance of natural light in the surface monotonously increases to the wavelength in a visible light region, and further, the points of inflexion are provided in the range of 520 to 600 nm wavelength. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a composite material containing Pt and Cu and an ornament using at least a part thereof.

  In recent years, there has been a demand for multicolored Pt due to diversification of preferences. For example, a pink metal material containing Pt includes a mixture of In—Pd and an intermetallic compound of a Pt—In alloy (see, for example, Patent Document 1).

In addition, attempts have been made to develop various colors by adding Cu to an intermetallic compound PtAl ₂ of Pt and aluminum (Al) or by melting Pt.Al.Cu together (for example, patents). Reference 2).

In such metal materials of Patent Literatures 1 and 2, the wavelength dependence of the reflectance in the visible light region is large in the red wavelength region and small in the blue wavelength region, so that the pink color development becomes stronger. It was to control (refer FIG. 3, FIG. 4).
JP 2000-226625 A JP-A-3-158430

    However, in Patent Document 1, the Pt content is 12% by weight, and if the Pt content is further increased, gray or yellow is exhibited, and a good pink color development cannot be expected.

On the other hand, in Patent Document 2, since the intermetallic compound PtAl ₂ of Pt and Al is added with Cu, or formed by melting together Pt.Al.Cu, the entire surface is mirror polished. It becomes a difficult intermetallic compound, and it is difficult to obtain a good Pt brightness.

  Further, in many metal materials such as Patent Documents 1 and 2, the wavelength dependency of the reflectance has a minimum value in the blue wavelength region and a maximum value in the red wavelength region. In the case of such a metal material, the extreme value is likely to fluctuate sensitively depending on the manufacturing conditions, so that there may be a problem that the target color tone is not stable.

  For example, in FIG. 3, the reflectance on the red wavelength side is high and the reflectance on the blue wavelength side is low. However, such a gentle change cannot secure a high wavelength in a wide range of the red wavelength region. . Furthermore, it becomes difficult to obtain an aesthetic pink color due to the influence of yellow to green wavelengths.

  Further, for example, in FIG. 4, there is a minimum value particularly in the blue wavelength region, the wavelength at which the minimum value is located is likely to fluctuate, and further tends to increase on the low wavelength side, making it difficult to obtain a stable pink color.

  An object of the present invention is to stably provide a pink composite material and a decorative article having excellent aesthetics.

  In the first aspect of the present invention, one or a plurality of first phases mainly composed of Pt and one or a plurality of second phases containing Cu are provided, and the reflectance of natural light on the surface is The wavelength dependency curve is monotonically increased from a wavelength of 400 to 700 nm, and an inflection point is in a wavelength range of 520 to 600 nm.

  Furthermore, the value of the second derivative indicating the wavelength dependence curve of the reflectance changes in the order of positive and negative from the wavelength of 400 to 700 nm.

  Further, the reflectance is 70% or more at a wavelength of 680 nm and 55% or less at a wavelength of 400 nm.

  Furthermore, the first phase includes at least a Pt element that does not constitute an intermetallic compound, the second phase includes at least an intermetallic compound of Au and Cu, and the first phase and the second phase are included in the first phase and the second phase. The content of the metal element present is Pt 25 to 75% by mass, Cu 15 to 46% by mass, Au 9 to 25% by mass, Pd 1 to 4% by mass, and the total of Pt, Cu, Au and Pd is 99% by mass or more. It is characterized by being.

  Moreover, the 2nd side surface of this invention provides the ornament formed with the said composite material.

  According to the present invention, the wavelength dependence curve of the reflectance of natural light on the surface has one or more first phases mainly containing Pt and one or more second phases containing Cu. However, since the inflection point is in the wavelength range of 520 to 600 nm, the reflectance is stable and high in the red wavelength region, and the reflectance is rapidly increased in the yellow and green wavelength regions. Since the reflectance can be further lowered in the blue wavelength region, mixing of different colors other than red is reduced. In addition, since there is no extreme value in the wavelength dependency curve of reflectance in the visible light region, it is possible to reduce color instability due to fluctuations in the wavelength position of the extreme value.

  As a result, it is possible to provide a stable pink composite material that is excellent in aesthetics and less affected by manufacturing conditions.

  In the following, the composite material and the decorative article according to the present invention will be described with reference to FIGS.

  One embodiment of the present invention has one or more first phases containing Pt as a main component and one or more second phases containing Cu, and the wavelength dependence of the reflectance of natural light on the surface The characteristic curve monotonously increases over the wavelength range of 400 to 700 nm, and the inflection point is in the range of the wavelength range of 520 to 600 nm.

  For example, in FIG. 1, the first phase 11 is a composite material 1 containing Pt as a main component and the second phase 12 being a main component containing Cu. Such a wavelength dependence curve of the reflectance of the composite material 1 is as shown in FIG. 2, for example, and it is easy to maintain a high reflectance in the red wavelength region. In the yellow to green wavelength region, since the reflectance can be rapidly reduced, it is easy to obtain a bright pink color that does not mix the yellow and green wavelengths. Furthermore, since the reflectance in the blue wavelength region can be stably suppressed, it is easy to obtain a bright pink color that does not mix the blue wavelength.

  Here, the inflection point of the wavelength dependence curve of the reflectance is the wavelength dependence data of the reflectance (measured in units of 1% and the wavelength in units of 10 nm with a visible light region of 400 to 700 nm) Can be obtained from the second derivative of the curve obtained by the least square method.

  Furthermore, in one embodiment of the present invention, it is preferable that the value of the second derivative of the function indicating the wavelength dependency curve of the reflectance changes in the order of positive and negative from the wavelength of 400 to 700 nm.

  Hereinafter, the value of the second derivative in the visible light region is expressed as a convex / concave curve, and the value of the second derivative in the visible light region is expressed as a concave / convex curve.

  It is easier to reduce the reflectance on the short wavelength side of the blue wavelength region than the curved surface of the concave / convex curve, and the change in reflectance in the yellow to green wavelength region (from blue wavelength region to red) (Change in reflectance to the wavelength region) can be made steep, and the reflectance in the red wavelength region can be stably maintained high. As a result, the hue of pink color can be made difficult to change.

  In one embodiment of the present invention, the reflectance is preferably 70% or more at a wavelength of 680 nm and 55% or less at a wavelength of 400 nm. Within this range, the difference in reflectance between the red wavelength region and the blue wavelength region is made more prominent, thereby making it easier to realize a pink color with high aesthetics. In addition, about the measurement of these reflectances of the composite material 1, the sample grind | polished in the range whose arithmetic mean surface roughness is 0.030 micrometer or more and 0.054 micrometer or less is used.

Further, in one embodiment of the present invention, the first phase has at least a Pt element that does not constitute an intermetallic compound, the second phase has at least an intermetallic compound of Au and Cu, and the first phase The content of the metal element present in the first phase and the second phase is Pt 25 to 75% by mass, Cu 15 to 46% by mass, Au 9 to 25% by mass, Pd 1 to 4% by mass, Pt, Cu, Au and Pd Is preferably 99% by mass or more. In order to create a pink-based color Pt, it can be achieved by keeping the colored metal in the Pt without dissolving it, so that the tint is not too close to the color of copper. Can do. This is because the ratio of the red intermetallic compound AuCu ₃ can be increased with respect to the metallic white intermetallic compound PtCu, and this composition is Cu consumed as PtCu or AuCu ₃ to realize this. It is blended in consideration of the composition. The composition can be calculated by EDS (energy dispersive X-ray analysis) semi-quantitative analysis. That is, it is possible to detect characteristic X-rays generated from a depth region of several μm from the surface, perform each elemental analysis, and calculate the composition from the peak intensity.

  Next, the method for producing the composite material of the present invention will be described by taking as an example the case where the ring 1 is formed by the discharge plasma sintering method.

  First, the content of metal elements present in the entire composite material is Pt 25 to 75% by mass, Cu 15 to 46% by mass, Au 9 to 25% by mass, Pd 1 to 4% by mass, and the total of Pt, Cu, Au, and Pd A mixed powder of Pt powder containing Pt and Cu powder containing Cu is prepared so that the average particle size is 45 to 106 μm and the purity is 99.9% or more so Is preferred.

  Next, the mixed powder is filled into a sintered mold and molded into a ring shape, and then a pulsed current is applied to the molded body at a low voltage in a vacuum atmosphere. Thereby, discharge plasma is instantaneously generated in the gaps between the particles of the molded body, and the molded body is sintered. Here, the molding pressure when forming the molded body is, for example, 100 MPa or more and 550 MPa. No pores are generated in the composite material 1 and the mold is not damaged due to stress concentration caused by filling the raw material. The firing temperature is, for example, 200 ° C. or more and 500 ° C. or less. If the firing temperature is 200 ° C. or more and 500 ° C. or less, it will not become brittle due to poor sintering or over firing. The applied pulse voltage is, for example, 4 V or more and 20 V or less. When the applied pulse voltage is set to 4 V or more and 20 V or less, sufficient discharge occurs and abnormal discharge is difficult to occur, so that the intended tissue state can be easily obtained. The sintering time including the temperature raising and holding time is a relatively short time of about 5 to 20 minutes.

  The present invention is not limited to decorative items such as rings, necklaces, bracelets, watches, and glasses, but can be used as, for example, tableware, figurines, golf clubs, mobile phones, and buttons.

Example 1
First, an embodiment will be described with respect to the correspondence between the wavelength dependency of reflectance, hue, and stability thereof.
(Sample preparation)
The mixed powder was formed into a ring shape in a sintered mold and then formed into a ring shape by a discharge plasma sintering method. The sample size was set to an inner diameter of 19.8 mm, an outer diameter of 23 mm, and a thickness of 5 mm.

  Specifically, a Pt powder containing Pt and a Cu powder containing Cu, 25 to 75 mass% of Pt, 15 to 46 mass% of Cu, 9 to 25 mass% of Au, and 1 to 4 mass of Pd The mixed powder was controlled so that the total of Pt, Cu, Au and Pd accounted for 99.9% by mass. As the Pt powder and the Cu powder, those having an average particle diameter of 45 to 106 μm and a purity of 99.9% or more were used. The molding pressure was 100 MPa to 550 MPa, the firing temperature was 200 ° C. to 500 ° C., the applied pulse voltage was 4 V to 20 V, and the sintering time was controlled in the range of 5 to 20 minutes.

  When the inflection point on the short wavelength side of the wavelength dependence of the reflectance is the inflection point 1 and the inflection point on the long wavelength side is the inflection point 2, the reflectivity at the inflection point 1 is 43 to 47%. The reflectance at the inflection point 2 is in the range of 73 to 77% and is comparatively evaluated (except for Reference Examples 5 and 6). Here, the inflection points 1 and 2 of Reference Examples 1, 2, 3, and 4 can be adjusted by controlling the particle size of the raw material, and the reflectances at 400 nm and 680 nm of Reference Examples 5 and 6 are Pt and Cu. It can be adjusted by controlling the ratio. Usually, the curve of the wavelength dependency of the reflectance shows a convex-concave curve. Even a concave-convex curve can be used, but it is difficult to prepare the sample itself, and the convex-concave curve is more suitable for the effect of the present invention, so it will not be described here.

(Wavelength characteristics of reflectance)
The reflectance was measured using “CM-3700d” (Minolta Co., Ltd.) for a sample whose surface was mirror-finished. The mirror surface processing was performed by polishing with a buff so that the arithmetic average surface roughness Ra was in the range of 0.030 μm to 0.054 μm. The reference light source was set to “D65” as “standard illuminant for colorimetry (standard light) and standard light source” from JIS standard (Z-8720), and the viewing angle was set to 10 °. The wavelength characteristic was evaluated as the reflectance of the total reflected light when the peak wavelength was changed in the range of 400 nm to 700 nm.

(Color evaluation)
Table 1 shows the results of color evaluation using a Konica Minolta spectrophotometer CM-508d as a Lab analyzer and measuring according to JIS Z 8729. As ideal Lab, L = 80 or more, B = 3 to 6, and b = 6 to 10 are preferable.

(Stability)
Here, the stability of the sample is evaluated by the homogeneity of the tissue state. When the surface is observed with a 20 × factory microscope, the portion where the pink color is not developed is not confirmed. When X is confirmed, it is marked with x.

  The results are shown in Table 1.

(Consideration of results)
In Sample 1 (Reference Example 1), since the inflection point 1 is located at 500 nm, the hue is close to purple because the reflectance in the blue wavelength region is not sufficiently reduced. In Sample 5 (Reference Example 2), since the inflection point 2 is located at 620 nm, the reflectance is insufficiently reduced in the yellow to green wavelength region, so that the hue becomes close to orange.

  In Sample 12 (Reference Example 3 (A) of Patent Document 1) and Sample 13 (No. 5 of Reference Example 4 of Patent Document 2), since the reflectance is increased on the short wavelength side, the pink color is aesthetic. In addition, since it has a minimum value in the blue wavelength region, the uniformity is poor and the hue is not stable.

  On the other hand, in Samples 2, 3, 4, 6, 7, 8, 9, 10, and 11, both the inflection point 1 on the short wavelength side and the inflection point 2 on the long wavelength side are in the range of 520 to 600 nm. Since the reflectance on the short wavelength side can be reduced, a brighter pink can be exhibited. In particular, in the visible light region, if the projections are convex upwards, the reflectance on the long wavelength side can be obtained in an integrated manner, so that it is possible to exhibit a more stable and highly aesthetic pink color at any position. Become. Further, if the reflectances at 400 nm and 680 nm are separated, a more vivid pink color can be obtained.

(Example 2)
Next, an example is shown about the correspondence between the composition and the hue of the composite material.

(Sample preparation)
The composition of the whole powder was as shown in Table 2, and the others were produced in the same manner as in Example 1.

Here, in order to increase the proportion of the red intermetallic compound AuCu ₃ with respect to the metallic white intermetallic compound PtCu, the composition of Cu consumed as PtCu or AuCu ₃ is taken into consideration, so the ratio of Cu to Au Is generally fixed.
(Color evaluation)
Evaluation was performed in the same manner as in Example 1.

  The results are shown in Table 2.

(Consideration of results)
As can be seen from Table 2, first, regarding the hue, the sample No. 15-19, 21, and 22 were showing the visible pink color. In contrast, sample no. No. 14 (Reference Example 5) did not exhibit a pink color due to too much Pt composition. In terms of color, the sample No. Since 20 (Reference Example 6) had too little Pt, the original brightness (lightness) of Pt could not be obtained.

  From the above results, Sample No. As in 15-19, 21, and 22, it is possible to provide an aesthetic pink metallic luster that is maintained.

It is a schematic diagram which shows one Embodiment of the structure | tissue state in the composite material which concerns on this invention. It is a graph of the wavelength dependence of the reflectance of one Embodiment in the composite material which concerns on this invention. It is a graph of the wavelength dependence of the reflectance of one Embodiment in the conventional composite material. It is a graph of the wavelength dependence of the reflectance of one Embodiment in the conventional composite material.

Explanation of symbols

1 Composite Material 11 First Phase 12 Second Phase

Claims (5)

  The wavelength dependency curve of the reflectance of natural light on the surface has one or a plurality of first phases containing Pt as a main component and one or a plurality of second phases containing Cu, and has a wavelength of 400 to 700 nm. A composite material characterized in that the inflection point is in a wavelength range of 520 to 600 nm while monotonously increasing over time.   2. The composite material according to claim 1, wherein a value of a second derivative indicating a wavelength dependency curve of the reflectance changes in the order of positive and negative from a wavelength of 400 to 700 nm.   The composite material according to claim 1 or 2, wherein the reflectance is 70% or more at a wavelength of 680 nm and 55% or less at a wavelength of 400 nm.   The first phase has at least a Pt element that does not constitute an intermetallic compound, the second phase has at least an intermetallic compound of Au and Cu, and exists in the first phase and the second phase. The metal element content is Pt 25 to 75% by mass, Cu 15 to 46% by mass, Au 9 to 25% by mass, Pd 1 to 4% by mass, and the total of Pt, Cu, Au and Pd is 99% by mass or more. The composite material according to any one of claims 1 to 3. An ornament using the composite material according to any one of claims 1 to 4.

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