TW201529890A - Article with metal oxide film - Google Patents

Abstract

Provided is an article with a metal oxide film, which has a novel configuration with color and metallic luster. Disclosed herein is an article with a metal oxide film, which is provided with a base that is formed of a metal material and a metal oxide film that covers the surface of the base and is formed of a metal oxide. This article with a metal oxide film is characterized in that the metal oxide film is formed by polishing the surface of the base with use of particles that are formed of the metal oxide.

Description

Article with metal oxide film

The present invention relates to articles having a metal oxide film attached thereto. The present application claims the priority of Japanese Patent Application No. 2013-258722, filed on Dec.

As a base material for electronic appliances, household groceries, sports, health products, automobile exterior parts, building materials, and other various items represented by household electrical appliances, various metal materials are used. The surface of such a metal material is subjected to various surface treatments using coating (coating) of a resin material, a ceramic material, a glass material, a metal material, or the like for the purpose of surface protection or designing of a pattern. Among them, in terms of electronic equipment, automotive interior components, etc., the requirements for surface design are extremely high, and processing that strongly reflects the user's preference is required. For example, surface coating of various metal materials by various printing techniques, chemical vapor deposition methods, physical vapor deposition methods, and attachment of decorative materials is generally widely used.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Laid-Open No. 185365

[Patent Document 2] Japanese Patent Application Laid-Open No. 201069

[Patent Document 3] Japanese Patent Application Laid-Open No. 256555

[Patent Document 4] Japanese Patent Application Laid-Open No. Hei No. 036819

Further, in the surface processing of the metal material, for example, a surface pattern designer whose texture is completely different from the metal material and a material feeling originally used for the metal material are generally obtained by coating or the like of various materials as described above. Surface processing, etc. In addition, as the surface processing for the material feeling of the metal material, for example, in addition to the processing such as the thin line processing or the sand blasting, the method of polishing the surface of the metal to improve the gloss of the metal is known. As a conventional technique related to the polishing of the metal material, for example, Patent Documents 1 to 4 can be cited.

Further, in the surface processing of a metal material, it is required to realize various pattern design properties in accordance with the preference of the user who uses the processed product. As an example, it is required to realize the gloss of a metal material with various colors. Also, it is better to make the gloss have a variety of styles to be Now. In this way, as long as the article composed of the metallic material with color and gloss can be realized by a more diverse configuration, the public opinion can improve the design of the article, and can also expand its use form or use. Moreover, it is desirable because it can provide articles that can be more widely and flexibly adapted to the requirements of the user.

The present invention has been made in view of the above-described viewpoints, and an object of providing a metal oxide film-attached article having a novel composition of color and metallic luster is provided.

In order to solve the above problems, the metal oxide film-attached article according to the present invention includes a base material made of a metal material and a metal oxide composed of a metal oxide covering the surface of the base material. In the film, the metal oxide film is formed by polishing the surface of the base material by using particles composed of the metal oxide (hereinafter simply referred to as "metal oxide particles").

In the article with a metal oxide film, the surface of the metal substrate is directly coated with a metal oxide film without passing through a binder component or the like. The metal oxide film is formed by embedding metal oxide particles on the surface of a metal substrate by polishing. Thus, the surface of the metal material can be covered by the metal oxide particles, but the article still has a metallic luster. Further, by using a polishing technique, particles composed of a metal oxide are buried in the surface of the metal substrate to form a dense and uniform film. Moreover, it can give the desired color and uniqueness to the metallic luster of the metal oxide particles. style of. That is, the article with the metal oxide film disclosed herein can achieve color and metallic luster by an unprecedented composition.

In addition, the term "polishing" in the present specification means an operation of placing metal oxide particles on the surface of the substrate to relatively move the two in a direction parallel to the surface of the substrate, and does not necessarily mean smoothing the surface of the substrate. The operation carried out for the purpose.

In a preferred embodiment of the metal oxide film-attached article disclosed herein, the particles having the metal oxide have an average primary particle diameter of 10 nm or more and 1 μm or less. According to the above configuration, it is possible to provide an article in which the thickness of the metal oxide film is more uniform and the color and gloss described above can be further effectively exhibited.

A preferred embodiment of the article with a metal oxide film disclosed herein is characterized in that the substrate is composed of a metal material having a Brinell hardness of 10 or more and 200 or less. According to the base material of the above configuration, the metal oxide particles can be held on the surface in a more intimate state. Thereby, the glossiness of the substrate can be improved, and the design of the pattern can be maintained for a long period of time.

In a preferred embodiment of the metal oxide film-attached article, the metal oxide particles are one or more selected from the group consisting of zirconia, cerium oxide and aluminum oxide.

According to the above configuration, it is possible to provide a metal oxide film-attached article which can easily realize gloss and color in a manner different from the physical properties of each metal oxide particle, and has various pattern designs.

A preferred embodiment of the article with a metal oxide film disclosed herein is characterized in that the substrate is aluminum or an aluminum alloy. according to According to the above configuration, it is possible to provide a metal oxide film-attached article which has a higher gloss and is lightweight and rich in workability. For example, it is possible to provide a metal oxide film-containing article which is rich in luster and full of high-grade feeling.

1‧‧‧Articles with metal oxide film

2‧‧‧Substrate

3‧‧‧Metal oxide film

Fig. 1 is a view showing a scanning electron microscope (SEM) image of a cross section of an article with a metal oxide film according to an embodiment.

Hereinafter, a suitable embodiment of the present invention will be described. Further, matters other than those specifically mentioned in the present specification, that is, what is required for the implementation of the present invention, can be grasped as a matter of design based on the prior art in the art. The present invention can be implemented based on the contents disclosed in the present specification and technical common knowledge in the field.

Further, the dimensional relationship (length, width, thickness, and the like) in the drawings indicates the general shape of the article with the metal oxide film of the present invention, and does not necessarily reflect the dimensional relationship in the actual article.

[Composition of articles with metal oxide film]

Fig. 1 is a cross-sectional observation image of a vicinity of a surface obtained by observing a cross section of an article with a metal oxide film according to an embodiment of the present invention by a scanning electron microscope (SEM). The article 1 with a metal oxide film disclosed herein is as shown in FIG. 1 and is essentially A base material 2 made of a metal material and a metal oxide film 3 made of a metal oxide covering the surface of the base material 2. Further, the metal oxide film 3 is formed by polishing the surface of the substrate 2 with particles made of a metal oxide.

[substrate]

The metal material constituting the substrate 2 is not particularly limited, and a monomer (i.e., a pure metal) or an alloy of various metals can be used. In addition, the term "alloy" as used herein means a substance composed of two or more elements and containing a substance exhibiting a metal property, and the blending method may be a solid solution, an intermetallic compound, or a mixture thereof. One. Specific examples of the metal material constituting the substrate 2 include typical elements such as Mg, Sr, Ba, Zn, Al, Ga, In, Sn, and Pb, and Sc, Y, Ti, Zr, and Hf. Transition metal elements such as V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Ag, Re, Os, Ir, Pt, Au, La, Ce, Pr, Nd, Sm, Eu, A simple substance such as a lanthanoid element such as Gd, Yb, Er, or Lu, or an alloy composed of such an element and one or more other elements. Of course, it is admissible that such metal materials are mixed with an unintended element in the form of unavoidable impurities or the like.

The base material 2 is not necessarily limited thereto, and if the Brinell hardness (HBW) is 10 or more and 200 or less, the metal oxide particles can be easily and strongly fixed to the surface thereof, which is preferable. In particular, it is suitable for fixing the metal oxide particles to the surface by a polishing technique or the like described later. When the Brinell hardness is 150 or less, The metal oxide particles are more easily fixed, and the metal oxide particles and the substrate 2 can be closely attached, which is preferable. On the other hand, if the base material 2 is too soft, its use is limited or vice versa, and the force for holding the metal oxide particles is weakened, which is not preferable. Based on the above viewpoint, the Brinell hardness is preferably 15 or more, and even more preferably 20 or more.

Specific examples of the metal material satisfying such Brinell hardness include aluminum (20), 1000-series aluminum alloy (15 to 25), 2000-series aluminum alloy (90 to 140), and 3000-series aluminum alloy (20~). 50), 4000 series aluminum alloy (100~200), 5000 series aluminum alloy (20~100), 6000 series aluminum alloy (50~100), 7000 series aluminum alloy (80~160), aluminum alloy, silver (24) , brass (90~100), bronze (40~100), cast iron (150~200), chrome steel (50~187), zirconium copper (50~140), S30C carbon steel for mechanical construction (130~200) Wait. Further, the numerical value expressed in the parentheses immediately after the above-mentioned metal material name is a representative Brinell hardness of the metal material.

In addition, "Brinell hardness" in this specification means the value measured by the Brinell hardness test-test method prescribed by JIS Z 2243:2008.

In addition, the substrate 2 has high reflectivity to visible light (for example, a light having a wavelength of about 360 nm to 830 nm, typically 400 nm to 760 nm), and is preferably designed to improve the design of the glossy surface. By. The reflectance varies depending on the wavelength of the light to be used, and cannot be generalized. Examples of the material having a high reflectance include gold, silver, copper, aluminum, platinum, iron, and the like. Further, as the substrate 2, for example, by using a metal material which can reflect a predetermined wavelength region in visible light, a metallic luster of a predetermined color can be obtained. Further, as the substrate 2, for example, it can be uniformly used through transmission. It is preferable to reflect the metal material in the wavelength region of the entire visible light line, and to obtain a so-called colorless metallic luster, and to more effectively utilize the optical action by the metal oxide film 3 to be described later. As the metal material having the colorless or nearly colorless metallic luster, silver, aluminum, aluminum alloy, or the like can be exemplified as a representative example. The base material 2 is preferably composed of aluminum or an aluminum alloy, in consideration of applications such as processing, ease of use, physical properties such as cost, reflectance, and hardness.

The shape (outer shape) of the substrate 2 is not particularly limited, and a metal material having a desired shape can be considered as the substrate 2. Further, in the article 1 with a metal oxide film disclosed herein, the metal oxide film 3 is suitably manufactured by grinding. Although it is not necessarily limited to this, considering the simplicity of the formation of the metal oxide film 3, the substrate 2 to which the article 1 to which the metal oxide film is attached is provided with at least a part having a flat surface. It is better. Regarding the flatness of the surface, for example, the substrate 2 to be used is preferably provided with flatness capable of achieving a so-called mirror surface. Here, as the mirror surface, for example, a surface having a surface roughness Ra of 20 nm or less, more preferably 10 nm or less can be used. By using such a flat substrate 2 to realize the metal oxide film-attached article 1, the reflection of light on the surface of the substrate of the article 1 with the metal oxide film can be suitably utilized as the gloss, and thus good. In addition, the material of the base material 2 (for example, Brinell hardness) may be different, and it is not possible to generalize the state in which the base material 2 and the metal oxide particles are in close contact with each other in the article 1 with a metal oxide film. At the same time, excessive light scattering by the article 1 can be suppressed. Thereby, the metal luster can be suitably maintained after the metal oxide film 3 is formed on the surface of the substrate 2.

Further, "surface roughness Ra" in the present specification means the arithmetic mean roughness Ra of the roughness of the surface property parameter defined by JIS B 0601:2013. The surface roughness Ra can be measured, for example, by using a commercially available non-contact surface shape measuring machine using a laser or the like.

Further, the size or thickness of the substrate 2 is not particularly limited. For example, in the range in which polishing can be performed, the substrate 2 in a desired form can be used. The substrate 2 is typically a sheet material, but is not limited thereto. Further, for example, the sheet material may be processed into a predetermined article shape or the like. Further, in the case of a sheet material, for example, it is not limited to a single layer material composed of a single layer, and may be a laminate material having a structure of two or more layers. When the base material 2 is a laminated material, the outermost surface of the metal oxide film 3 is formed, and as described above, it is preferably made of aluminum or aluminum alloy. Furthermore, the surface of the substrate 2 may be a curved surface or a flat surface, or may be at least a part of a curved surface or a flat surface, and the flat surface described above is provided with a convex portion. Further, when the surface is provided by the above-described flat convex portion, it is preferable that the metal oxide film 3 can be easily disposed only in the convex portion. At this time, for example, the convex portion may be formed into a desired pattern.

[Metal Oxide Film]

The surface of the substrate 2 is covered with a metal oxide film 3. Through the presence of the metal oxide film 3, the article 1 with the metal oxide film disclosed herein can have a unique pattern design having a variety of colors and gloss.

The metal oxide film 3 is typically composed of a metal oxide A collection of particles. The metal oxide particles may be bonded to each other to form a film, but it is not necessary that all of the metal oxide particles are integrally bonded. For example, the metal oxide particles may not be bonded to each other but may be present on the surface of the substrate 2 individually. The metal oxide particles are fixed to the surface of the substrate 2 by being closely adhered thereto, and the entire metal oxide particles can be regarded as a film. In the case where the plurality of metal oxide particles are bonded to each other, for example, as shown in Fig. 1, the metal oxide particles constituting the metal oxide film 3 can be confirmed as individual particles by observation by an electron microscope or the like. . For example, between tightly bound particles, the grain boundaries can still be grasped by comparison of SEM images. Based on this, the metal oxide film 3 can be clearly distinguished from a natural oxide film formed by being oxidized substantially uniformly on the surface of the substrate.

Further, the metal oxide film 3 can be formed by laminating one or two or more layers of the metal oxide particles on the surface of the substrate 2. In order to strongly fix the metal oxide particles to the substrate 2, it is preferred that the metal oxide particles are deposited on the surface of the substrate 2 in about one layer. Further, when the metal oxide particles can strongly fix the surface of the substrate 2, in the metal oxide film 3, the metal oxide particles may be deposited in two or more layers (typically 2 to 3 layers).

Further, the metal oxide particles are directly attached (fixed) to the surface of the substrate 2 without being passed through a binder component such as a resin. The attached mechanism does not necessarily have to be clarified. However, the present invention is not limited thereto, and can be realized, for example, by the surface activity of the fine metal oxide particles and the surface activation of the substrate 2 by polishing. Moreover, a weak contact force generated by electrostatic attraction or the like State can be excluded from the attachment referred to herein. Further, the adhesion may include a form in which the metal oxide particles are mechanically fixed to the substrate 2. More preferably, it may be in a state in which at least a part of the metal oxide particles are caught in the surface of the substrate 2. Further, it may be in a state of being in close contact with the interface between the metal oxide particles and the substrate 2. That is, the interface between the metal oxide particles and the substrate 2 is formed into a concavo-convex shape along the form of the metal oxide particles. Further, the metal oxide particles are fitted (engaged) with the substrate 2 by the uneven shape of the interface. For example, the interface is hybridized in three dimensions, and the metal oxide particles can be strongly fixed to the substrate 2. When the metal oxide particles are adhered to and fixed to the substrate 2 in this manner, for example, when the article 1 is used for a long period of time, the metal oxide particles can be prevented from falling off from the substrate 2 .

The metal oxide particles are not particularly limited in their composition, and may be particles composed of various metal oxides. Examples of the metal element constituting the metal oxide include a semimetal element selected from B, Si, Ge, Sb, and Bi, Mg, Ca, Sr, Ba, Zn, Al, Ga, In, Sn, and Pb. Typical elements, such as Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Ag, Re, Os, Ir, Pt, Au, etc. One or two or more kinds of lanthanoid elements such as elements, La, Ce, Pr, Nd, Sm, Eu, Gd, Yb, Er, and Lu. In addition, it is preferable that the metal oxide contains an oxide of one or two or more elements selected from the group consisting of Zr, Ce, Al, Ti, Cr, Mn, and Zn.

Further, the metal oxide film 3, that is, the metal oxide constituting the metal oxide particles, may be selected from those having a desired refractive index based on the color of the article 1 to which the metal oxide film is attached. Further, it is not particularly limited, but for example, in order to more suitably control the color of the article 1 to which the metal oxide film is attached, the metal oxide has a high refractive index. The refractive index of the metal oxide constituting the metal oxide particles is preferably 1.5 or more, more preferably 2 or more, and still more preferably 2.3 or more. As the metal oxide having a higher refractive index, for example, zirconia (ZrO ₂ ), cerium oxide (CeO ₂ ), alumina (Al ₂ O ₃ ), titanium oxide (TiO, Ti ₃ O ₅ ) can be specifically exemplified. , TiO _{2 ,} etc., tantalum pentoxide (Ta ₂ O ₅ ), niobium oxide (Nb ₂ O ₅ ), hafnium oxide (HfO ₂ ), and the like. Further, if the aesthetics under visible light is considered, it is preferable that the metal oxide is transparent in a single crystal state, and more preferably is colorless and transparent. From this point of view, as the metal oxide, for example, specifically, zirconium oxide (ZrO ₂ ), cerium oxide (CeO ₂ ), aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO, Ti ₃ O) ₅ , TiO _2, etc.) are preferred.

Further, the geometric shape (outer shape) of the metal oxide particles is not particularly limited, and for example, a spherical shape to an indefinite shape may be various shapes. Further, from the viewpoint of making the fixing of the metal oxide particles to the substrate 2 stronger, for example, it is preferable to deviate from the shape of a spherical shape (for example, a true spherical shape). For example, as a typical example, it is preferable to reflect the outer shape of the crystal system of the metal oxide constituting the metal oxide particles. The outer shape of the crystal system can be produced, for example, by performing a spheroidization treatment on the metal oxide particles, by a sufficient crystal growth process, and further by crushing or the like. By the presence of crystal faces, ribs, corners, corners, and the like in the metal oxide particles, the metal oxide particles are easily caught on the surface of the substrate 2, and the strong fitting can be realized more easily. Oxidation through metal The material particles 3 are crystal particles having high crystallinity, and are also preferable in that the optical action described later can be further improved.

The metal oxide particles may have an average primary particle diameter of 10 nm or more and 1 μm or less. If the average primary particle diameter is less than 10 nm, the metal oxide particles are less likely to be beneficial to the substrate 2, and it is not easy to have a variety of colors due to optical effects, which is not preferable. From the above viewpoint, the average primary particle diameter of the metal oxide particles is more preferably 30 nm or more, and still more preferably 50 nm or more. For example, it may be 100 nm or more. However, when the average primary particle diameter exceeds 1 μm, it is difficult to keep the surface of the metal oxide film-attached article 1 smooth, which is not preferable. Further, the metal oxide particles become large, and if the binder component is not used, the metal oxide particles may not be easily fixed to the substrate 2, which is not preferable. From the above viewpoint, the average primary particle diameter of the metal oxide particles is preferably 800 nm or less, more preferably 500 nm or less.

The average primary particle diameter of the above metal oxide particles can be grasped, for example, by observation with an electron microscope.

As a specific procedure for grasping the average primary particle diameter, for example, a predetermined number is obtained by an observation image obtained by an appropriate observation means such as an electron microscope on an arbitrary cross section of the article 1 with the metal oxide film attached thereto (for example, The diameter of the metal oxide particles of 100) is equivalent to the diameter of the circle, and the arithmetic mean value is calculated to obtain the average primary particle diameter.

In addition, the average thickness of the metal oxide film 3 composed of the metal oxide particles described above is not strictly limited, but is preferably in the range of 10 nm or more and 1 μm or less, and more preferably 30 nm or more. Below 600 nm. Irradiation to article 1 with metal oxide film The optical path of the light passing through the metal oxide film 3 is determined based on the thickness of the metal oxide film 3 or the like. By adjusting the optical path to a desired value, the color imparted to the article 1 to which the metal oxide film is attached and its effect can be varied variably.

Further, the average thickness of the metal oxide film 3 can be grasped by, for example, visual observation or image analysis based on electron microscope observation. For example, the observation image of the cross section of the metal oxide film obtained by the transmission electron microscope may be a value obtained by visually measuring the thickness of the film by about 3 to 10 dots per image.

Further, at the interface between the metal oxide particles and the substrate 2, a product or the like which is inevitably formed can be allowed to exist therein. The product is intended to include, for example, a metal oxide film formed of a metal material constituting the substrate 2, or other unintended reaction product or the like. The product or the like may be contained at the interface between the metal oxide particles and the substrate 2, and may be an acceptable form of the article 1 with a metal oxide film disclosed herein.

[pattern design]

The metal oxide film-attached article 1 having the above configuration can exhibit metallic luster from the substrate 2 regardless of whether or not the metal oxide film 3 is provided on the surface thereof. Further, for example, when the article 1 to which the metal oxide film is attached is viewed from a direction orthogonal to the surface (so-called front surface), the appearance is substantially the same as that of the substrate 2 alone. However, when the article 1 with the metal oxide film is viewed from the direction in which the surface is inclined, the metallic luster may be mainly accompanied by a mixed color of red, orange, yellow, green, blue, purple, and the like, or white. Ren A color (hue). Further, depending on the configuration of the article 1 to which the metal oxide film is attached, the metallic luster may be sometimes accompanied by the color when viewed from the front. This color can be expressed in a unique style based on the structure of the metal oxide film 3, which is also called "a collection of metal oxide particles." For example, it is possible to form a gloss having a stable feeling in which a so-called dazzling metallic feeling which is visible in a color plating product or the like is relaxed.

Such a metal oxide film-attached article 1 can achieve a beautiful and gorgeous appearance as described above, in addition to the configuration of the metal oxide film-attached article 1 and optical action. Further, the appearance can be subtly changed depending on the angle of the article 1 to which the metal oxide film is attached, the light source at the time, and the like. That is, the degree of coloration (e.g., color density) or degree of brilliance, hue, and the like may vary subtly. Such an article 1 with a metal oxide film can be an article with an unprecedented color and gloss, excellent pattern design, and high aesthetics.

The pattern designability of the article 1 with the metal oxide film as described above can be evaluated and managed based on, for example, the following indicators.

<gloss>

The greatest feature associated with the design of metallic materials is the reflection of light and the metallic luster. Moreover, the article 1 with a metal oxide film disclosed herein can also be evaluated for the metallic luster based on the substrate 2 by, for example, glossiness. The gloss can be measured based on, for example, a method for measuring specular gloss as described in JIS Z8741:1997. Based on the glossiness, it is possible to evaluate whether or not the article 1 with the metal oxide film attached as the object of evaluation has Appropriate gloss for the design of the application or the required pattern. Further, the surface reflection characteristics of the metal oxide film-attached article 1 can be evaluated, for example, by obtaining a generally known bidirectional reflection distribution function (BRDF).

<color>

The color (color) of the surface of the article 1 with a metal oxide film disclosed herein can be evaluated and managed based on, for example, hue, lightness, chroma, and the like. The color to which the article 1 with the metal oxide film disclosed herein is evaluated includes the color tone of the metal material constituting the substrate 2 and the color tone emitted by the action of the light realized by the metal oxide film 3. The evaluation may be evaluated based on, for example, a sensory evaluation of a human body, or a display method of a color prescribed by JIS Z 8730:2009. The sensory evaluation of the human body can be accompanied by a weighting of the characteristics or use of the evaluation object to achieve a more practical evaluation. Moreover, according to the evaluation of the color display, for example, the color can be numerically converted into a uniform color space (UCS) by hue, brightness, and chroma, and a more objective evaluation can be achieved.

Further, here, the reason why the article 1 with the metal oxide film is provided with the unique color and gloss as described above is not necessary, but, for example, it is considered that the optical effect as follows can be exhibited.

That is, in the article 1 with a metal oxide film disclosed herein, the metal oxide particles constituting the metal oxide film 3 are generally fine in size as described above, and generally have high crystallinity and are visible to visible light. It is colorless and transparent. Therefore, regarding a metal oxide film having the above structure 3. Also, similar to the essential characteristics of the metal oxide particles, the visible light has high penetrability and can be transparent (including colorless and transparent). In view of the above, the article 1 with the metal oxide film is coated with the metal oxide particles, but has the metallic luster produced by the metal material from the substrate 2.

On the other hand, the metal oxide constituting the metal oxide particles has a predetermined refractive index based on the composition. Therefore, light that is irradiated onto the surface of the article 1 to which the metal oxide film is attached and which is attached to the metal oxide film, and which is reflected by the metal oxide film 3 and reflected on the surface of the substrate 2 are emitted. A light path difference is generated between the lights. Thereafter, when the optical path difference becomes an integral multiple of the wavelength of the light of a predetermined color, the light of the wavelength is mutually enhanced by the interference phenomenon of light, and it seems that the article 1 with the metal oxide film is colored based on The color of the wavelength. The optical path difference varies depending on the refractive index of the metal oxide constituting the metal oxide film 3, the thickness of the metal oxide film 3, the angle of the article 1 to which the metal oxide film is attached, and the like. Therefore, based on the optical path difference, the article 1 with the metal oxide film can achieve a variety of hues accompanied by brilliance. Further, variability can be imparted to the color tone by observing the angle of the article 1 to which the metal oxide film is attached.

Further, as shown in FIG. 1, the metal oxide film-attached article 1 has an interface between the substrate 2 and the metal oxide film 3 and the surface of the metal oxide film 3 is not completely smooth. Further, an interface or a minute gap can be formed between the metal oxide particles constituting the metal oxide film 3 and the substrate 2. Therefore, the above-mentioned optical effects can be disturbed by the complicated and fine interface structure, and even vary in diversity. With this, For example, the gloss accompanying the above-mentioned color can be softened by the gradation of the metallic luster produced by the substrate 2. Further, when the article 1 to which the metal oxide film is attached is viewed from a predetermined angle, it is not limited to enhancing light of a specific wavelength, for example, by mixing light of various wavelengths or the like, or forming a metal oxide film. Item 1 has a brilliant white (milk white).

[Manufacture of articles with metal oxide film]

The article 1 with a metal oxide film disclosed herein can be suitably produced, for example, by the method shown below. That is, in the method for producing the metal oxide film-attached article 1, metal oxide particles can be supplied to the surface of the substrate 2, and the substrate 2 can be polished using the metal oxide particles. It is produced by directly fixing a metal oxide to the particle substrate 2. Therefore, the preferred method of producing the article 1 with a metal oxide film disclosed herein may include the step of forming the metal oxide film 3 by, for example, grinding the surface of the substrate 2 using the above-described metal oxide particles.

[Preparation of substrate]

As the substrate 2, various substrates composed of the above-described metal materials can be used. The substrate 2 is preferably provided with a flat surface portion on at least a part of its surface. The flat surface portion can be provided by polishing the surface of the substrate 2 before the formation of the metal oxide film 3 described above. The polishing may be performed by mirror polishing using a polishing liquid selected according to the material of the substrate 2. Although not particularly limited, the polishing is typically performed by, for example, chemical mechanical polishing using a slurry containing colloidal cerium oxide as a free abrasive. (Chemical Mechanical Polishing; CMP) is preferably implemented. The technique related to the mirror polishing is not related to the present invention, and thus its detailed description is omitted.

[Formation of Metal Oxide Film]

Next, the substrate 2 prepared as described above is polished using a liquid composition containing the metal oxide particles as a polishing liquid. The grinding can also be suitably carried out, for example, by using CMP techniques. That is, in the polishing using the liquid composition containing the metal oxide particles as the polishing liquid, in addition to the surface chemistry of the metal oxide particles themselves, the chemical composition of the polishing liquid may be used for the substrate 2 The role of the surface. Thereby, the surface of the substrate 2 can be adjusted to a state suitable for fixing the metal oxide particles, and the metal oxide film 3 can be formed by adhering and fixing the metal oxide particles to the substrate 2 in a tight and uniform manner.

Further, the grinding machine used for the polishing is not particularly limited, and for example, various commercially available grinding machines can be used. Specifically, for example, a so-called fixed type or portable type grinding machine, a metal working or a grinding machine for precision polishing, or the like can be used.

Here, the metal oxide particles contained in the liquid composition for polishing may be in the form of primary particles or secondary particles in which a plurality of primary particles are aggregated. Further, the metal oxide particles in the form of primary particles and the metal oxide particles in the form of secondary particles may be mixed. In a preferred embodiment, at least a part of the metal oxide particles are contained in the liquid composition in the form of secondary particles. Gold contained in the liquid composition The average primary particle diameter of the oxide particles may be a range in which the average primary particle diameter of the metal oxide particles constituting the metal oxide film 3 described above can be realized. That is, it may be an average primary particle diameter which is approximately equal to the average primary particle diameter of the metal oxide particles constituting the metal oxide film 3 described above.

Further, the average secondary particle diameter of the metal oxide particles is not particularly limited, and is preferably from about 10 nm to about 10 μm. The average secondary particle diameter of the metal oxide particles is preferably 50 nm or more, and more preferably 100 nm or more, from the viewpoint of the fixing efficiency of the metal oxide particles to the substrate 2 and the like. Further, from the viewpoint of forming the metal oxide film 3 having a more uniform thickness, the average secondary particle diameter of the abrasive is suitably 2 μm or less, preferably 1.5 μm or less, more preferably 1 μm or less.

Further, the average secondary particle diameter of the metal oxide particles may be a cumulative 50% particle diameter (D ₅₀ ) based on a volume-based particle size distribution measured by a commercially available particle size measuring device. As the particle size measuring device, any one of a dynamic light scattering method, a laser diffraction method, a laser scattering method, and a fine hole resistance method can be used.

In addition, the average primary particle diameter of the metal oxide particles contained in the liquid composition can be measured by an electron microscope observation similarly to the average primary particle diameter of the metal oxide particles constituting the metal oxide film 3 described above.

Further, in the liquid composition, the liquid medium for dispersing the metal oxide particles is also not particularly limited. For example, as a preferred example of the liquid medium, the same liquid medium as in the polishing liquid used in the conventional CMP can be used. The liquid medium is typically water-based, and may include a component for increasing the dispersibility of the metal oxide particles as needed. Powder or surfactant, even pH adjuster. The liquid composition may contain various additives used in such a field without greatly hindering the production of the article 1 to which the metal oxide film is attached. Further, depending on the material of the substrate 2, it is expected that the pH of the liquid composition may affect the form in which the metal oxide particles adhere to the substrate 2. The pH of the liquid composition is preferably adjusted to, for example, an alkali side (over pH 7; typically pH 8 to 13, for example, pH 9 to 11).

The polishing composition of the present invention may further comprise an etchant for promoting dissolution of the alloy material, an oxidizing agent for oxidizing the surface of the alloy material, a water-soluble polymer, a copolymer or a salt thereof acting on the surface of the alloy material or the surface of the abrasive, as needed. A derivative, an anticorrosive agent or a chelating agent for suppressing corrosion of the surface of the alloy material, a dispersing aid which facilitates redispersion of the aggregate of the abrasive, a preservative having other functions, an antifungal agent, and the like.

Examples of the etchant include inorganic acids such as nitric acid, sulfuric acid, and phosphoric acid, organic acids such as acetic acid, citric acid, tartaric acid or methanesulfonic acid, inorganic bases such as potassium hydroxide and sodium hydroxide, ammonia, amines, and quaternary ammonium salts. An organic base such as a hydroxide.

Examples of the oxidizing agent include hydrogen peroxide, peracetic acid, percarbonate, urea peroxide, perchlorate, and persulfate.

Examples of the water-soluble polymer, the copolymer, or a salt or a derivative thereof include polycarboxylic acid such as polyacrylate, polysulfonic acid such as polyphosphonic acid or polystyrenesulfonic acid, xanthan gum, sodium alginate, and the like. Cellulose derivatives such as polysaccharides, hydroxyethyl cellulose, carboxymethyl cellulose, polyethylene glycol, polyethylene Alcohol, polyvinylpyrrolidone, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, sorbitan monooleate, oxygenated alkyl group polymerization having a single or a plurality of oxygen alkyl units Things and so on.

Examples of the anticorrosive agent include amines, pyridines, tetraphenylphosphonium salts, benzotriazoles, triazoles, tetrazoles, benzoic acid, and the like.

Examples of the chelating agent include carboxylic acid-based chelating agents such as gluconic acid; amine-based chelating agents such as ethylenediamine, diethylenetriamine, and trimethyltetramine; ethylenediaminetetraacetic acid and nitrogen triacetic acid; a polyaminopolycarboxylic acid chelating agent such as hydroxyethylethylenediaminetriacetic acid, triamethylenetetraamine hexaacetic acid or diamethylenetriaminepentaacetic acid; 2-aminoethylphosphonic acid, 1-hydroxyethylidene -1,1-diphosphonic acid, aminotris(methylenephosphonic acid), ethylenediamine oxime (methylene phosphonic acid), diethylenetriamine penta (methylene phosphonic acid), ethane-1,1- Organic sulfonic acid chelating agents, phenol derivatives, bisphosphonic acid, ethane-1,1,2-triphosphonic acid, methane hydroxyphosphonic acid, 1-phosphonium butane-2,3,4-tricarboxylic acid, 1,3-diketone and the like.

Examples of the dispersing aid include condensed phosphates such as pyrophosphate or hexametaphosphate. Examples of the preservative include sodium hypochlorite and the like. Examples of the antifungal agent include oxazolines such as oxazolidine-2,5-dione.

Next, the liquid composition described above is supplied as a polishing liquid to the substrate 2 which is an object to be polished, and is polished by a usual method. At the time of the polishing, for example, the substrate 2 is fixed to a general polishing apparatus, and the polishing liquid is supplied to the surface (the polishing target surface) of the substrate 2 by the polishing pad of the polishing apparatus. Typically, the polishing liquid is continuously supplied while the polishing pad is in contact with the surface of the substrate 2, and the two are relatively moved (for example, rotated) move). By the polishing step, metal oxide particles are adhered and fixed to the surface of the substrate 2, and the formation of the metal oxide film 3 is completed. Thereby, the article 1 with the metal oxide film disclosed herein is produced.

Further, the polishing pad used in the above polishing step is not particularly limited. For example, any of a non-woven type, a felt type, an abrasive-containing one, and an abrasive-free one can be used.

Further, the article 1 with the metal oxide film produced as described above is typically cleaned after grinding. This cleaning can be carried out using a suitable cleaning solution.

[use]

The article 1 with a metal oxide film disclosed herein is provided for imparting gloss to a surface of a metal material having various materials and shapes, and has a high pattern design property. Therefore, it can be suitably applied to a constituent member constituting various products, and particularly a member requiring a high degree of pattern design and aesthetics. As the member, it is typically a member that can be used for various articles of commercial use, for example, an article that provides a variety of pattern designs to a general user. Specifically, for example, it can be used as a variety of electrical appliances, conditioning equipment, indoor and outdoor products, such as household goods, window frames, door materials, and other materials, such as automobiles, bicycles, and locomotives. Use.

Further, on the other hand, the metal oxide film-attached article 1 disclosed herein has a metal oxide film 3 made of a metal oxide on its surface. Thus, the surface of the substrate 2 can be formed by the metal The metal oxide of the oxide film imparts various functionalities. One or more of the above-mentioned functions include corrosion resistance, heat resistance, abrasion resistance, and chemical stability. Further, the article 1 with the metal oxide film disclosed herein can reduce the gloss as compared with the mirror surface. From the above viewpoint, the metal oxide film-attached article 1 can be suitably applied to an optical article application requiring control (typically suppression) of light reflectance characteristics.

In the following, several embodiments of the invention are described, but are not intended to limit the invention to the embodiments shown.

(Examples 1~12)

A sheet of "Al1070", "Al5052", and "Al6063" made of three kinds of aluminum alloys is commercially available, and is cut into a size of 32 mm × 32 mm, which is referred to as a substrate 1 to 3 in order. Further, the number of the four digits after the base material indicates the alloy number of the aluminum alloy sheet specified in JIS H4000:2006, etc., and each base material has a composition corresponding to the alloy number. Further, the Brinell hardness (10/500) of the substrates 1 to 3 was a substrate of 1:26 to 75, a substrate of 2:60 to 77, and a substrate of 3:60.

These substrates were placed on a carrier of a grinder, and first, mirror polishing was performed to have a surface roughness Ra of about 5 nm.

Next, the mirror-polished surface of the substrate was polished using a liquid composition containing the metal oxide particles shown in the following Examples 1 to 12 as a polishing liquid. In addition, the grinding conditions in the grinding are as follows:

<Example 1~3>

A liquid composition containing zirconia particles having an average secondary particle diameter of 0.9 μm at a content of 200 g/L was prepared to prepare a polishing liquid.

Further, the liquid composition of Example 1 was adjusted to pH 3.0 with citric acid.

The liquid composition of Example 2 was pH 6.0.

The liquid composition of Example 3 was adjusted to pH 10.0 with potassium hydroxide.

<Example 4~6>

A liquid composition containing cerium oxide particles having an average secondary particle diameter of 1.4 μm at a content of 200 g/L was prepared to prepare a polishing liquid.

Further, the liquid composition of Example 4 was adjusted to pH 3.0 with citric acid.

The liquid composition of Example 5 was pH 6.7.

The liquid composition of Example 6 was adjusted to pH 10.0 with potassium hydroxide.

<Example 7~9>

A liquid composition containing alumina particles having an average secondary particle diameter of 1.2 μm at a content of 200 g/L was prepared to prepare a polishing liquid.

Further, the liquid composition of Example 7 was adjusted to pH 3.0 with citric acid.

The liquid composition of Example 8 was pH 7.1.

The liquid composition of Example 9 was adjusted to pH 10.0 with potassium hydroxide.

<Example 10~11>

A liquid composition containing colloidal cerium oxide having an average secondary particle diameter of 60 nm at a content ratio of 18% by mass was prepared to prepare a polishing liquid.

Further, the liquid composition of Example 10 was adjusted to pH 4.0 with citric acid.

The liquid composition of Example 11 was adjusted to pH 7.0 with potassium hydroxide.

The liquid composition of Example 12 was adjusted to pH 10.0 with potassium hydroxide.

[grinding conditions]

Grinding machine: single-side grinding machine (fixing diameter 380mm)

Abrasive pad: felt type

Grinding load: 175g/cm ²

Number of rotations: 90rpm

Line speed: 72m/min

Grinding time: 10 minutes

Temperature of the slurry: 20 ° C

Feeding speed of the slurry: 14ml/min

Further, the types of the metal oxide particles contained in the liquid compositions of Examples 1 to 12 and the pH of the liquid composition are shown in Table 1 below. Using the polishing system of the liquid compositions of Examples 1 to 3, the substrates 1 to 3 were simultaneously placed on a carrier of a grinder, and polishing was carried out under the same conditions.

The average secondary particle diameter of the metal oxide particles contained in the liquid compositions of the above Examples 1 to 9 is a particle size measuring device measured by a laser diffraction/scattering particle size distribution (LA-made by Horiba, Ltd.) 950) measured value.

The average secondary particle diameter of the agglomerated particles of colloidal cerium oxide contained in the liquid composition of the above examples 10 to 12 is determined by a particle size measuring device (UPA-UT151 manufactured by Nikkiso Co., Ltd.) according to a dynamic light scattering method. Value.

The polishing surface of the substrate obtained by polishing the liquid composition of the above Examples 1 to 12 (hereinafter, simply referred to as "the substrate of Example 1") was subjected to the following color tone, gloss, and chromaticity. The surface roughness was measured and the results are shown in Table 1. In addition, each rating is implemented under the following conditions.

<hue>

The color tone of the polished surface of the ground substrate after the polishing was visually evaluated. The evaluation criteria were based on the metallic luster of the surface of the substrate after specular polishing, and the hue of the substrate was evaluated as being classified into red, orange, yellow, green, blue, purple, white, black, and no change. The results are shown in the "Hue" column of Table 1 below. In addition, the "-" in the table indicates that there is no special change in the hue of the surface (no change).

<degree of coloration>

The degree of coloration of the ground surface of the ground substrate after the polishing was evaluated by visual observation in stages of 0 to 5. As far as the evaluation criteria are concerned, the higher the value, the more intense the color, and the degree of coloration 0 means the metallic gloss without color (ie, equivalent to the metallic luster on the mirror-polished surface). The results are shown in the column "Color rendering degree" in Table 1 below.

<gloss>

The glossiness of the polished surface of the substrate after polishing was measured by using a gloss meter "GM-268 Plus" manufactured by KONICA MINOLTA OPTICS Co., Ltd., and measuring the angle of 20°, based on the method of measuring the specular glossiness described in JIS Z8741:1997. The results are shown in the column of "Glossiness" in Table 1 below.

<surface roughness>

The surface roughness Ra of the polished surface of the substrate after polishing was measured by a non-contact surface shape measuring machine (NewView 5032 manufactured by ZYGO Co., Ltd.) and a measurement field of view of 1.4 mm × 1.1 mm. The results are shown in the column "Ra" in Table 1 below.

As shown in Table 1, it was confirmed that the surfaces of the substrates of Examples 1 to 9 were able to maintain the metallic luster while exhibiting white, yellow to red. From this, it was confirmed that the substrates of Examples 1 to 9 were given pattern design properties having a unique color and gloss height. On the other hand, the surface of the substrate of Examples 10 to 12 maintained a strong metallic luster, but the coloration could not be confirmed. Further, the glossiness of these substrates was confirmed to be low in the substrates of Examples 1 to 9 which were colored, and extremely high in the substrates of Examples 10 to 12 which were not colored. Also, because of the degree of coloration, the sensory evaluation It is not rigorous, but it can be seen that the higher the degree of coloration, the lower the gloss.

As described above, it is expected that the color imparted to the substrates of Examples 1 to 9 is caused by adhesion and fixation of various metal oxide particles contained in the liquid composition used as the polishing liquid to the substrate. Further, it is expected that the substrate of Examples 10 to 12 is not colored. The metal oxide particles contained in the liquid composition used as the polishing liquid are colloidal cerium oxide, and since the shape is slightly spherical, the grinding is performed this time. It is not easy to adhere to the substrate under the conditions.

Further, although the specific results were not shown, the results of observing the surface of the substrate 3 of Example 3 after polishing by a transmission electron microscope confirmed that the surface of the substrate 3 of Example 3 was from about 50 nm to 100 nm in diameter. The left and right particles are covered. As a result of observing the cross section of the substrate 3 after the polishing, it was confirmed that the particles adhered to the surface of the substrate 3 so as to adhere to the film shape of one layer or two layers. In addition, it was confirmed that these particles were adhered in a state in which the surface of the base material 3 was adhered to a film having a thickness of about 100 nm. It is understood that this is a size and shape approximately coincident with the primary particles of zirconia contained in the polishing liquid. Further, the surface roughness Ra of the substrate 3 of Example 3 can be inferred to be caused by the arrangement of the particles.

Furthermore, as a result of analyzing the composition of the cross section of the substrate obtained by the EDX of the substrate 3 of Example 3, it was confirmed that these particles are metal oxides contained in the liquid composition used as the polishing liquid (oxidation) Zirconium) particles. Further, it was confirmed that the size and shape of the particles adhering to the substrate were approximately the same as the size and shape of the primary particles constituting the zirconia particles, and the shape of the zirconia-free particles was largely deformed. Also, you can confirm this The zirconia particles are present on the surface of the substrate in such a manner as to form a film having a thickness corresponding to its size (for example, primary particle diameter). Thus, it was confirmed that the substrate 3 to which the liquid composition of Example 3 was used was polished, that is, the article with the metal oxide film disclosed herein was formed.

From the above results, it was found that the surface of the substrate of Examples 1 to 9 having the surface color was similar to the surface of the substrate 3 of Example 3, and metal oxide particles were adhered thereto to form an article with a metal oxide film. Further, from the surface roughness Ra of each of the substrates, it is inferred that each of the metal oxide particles adheres to the substrate in the form of primary particles, and the surface roughness Ra can be achieved by arranging the particles. On the other hand, in the substrates of Examples 10 to 12 which were not colored, it was also possible to infer that the coating was not formed by the glossiness or the like.

Further, the substrate of Example 3 was colored yellow to red, and the substrates of Examples 1, 2, and 4 to 9 were colored white, and it is considered that the structure of the metal oxide film formed by the metal oxide particles attached to each substrate was considered. And the effect of light. That is, the metal oxide film composed of the metal oxide particles attached to the substrate of Example 3, for example, the optical path difference determined by the refractive index and thickness thereof (which may be the density and distribution of the metal oxide particles) It is considered to be consistent with the condition that the light of the yellow or red wavelength can be interfered.

On the other hand, it is known that the optical path difference can be recognized as white if the optical path difference is as follows: (1) the optical path difference is smaller than the visible light wavelength; and (2) the case where the optical path difference greatly increases with each other. For the substrates of the other examples 1, 2, and 4 to 9, for example, it is considered that the state of the interface between the substrate and the metal oxide film or the structure of the metal oxide film is equal to any of the above conditions (1) and (2). The result is white.

As described above, it was confirmed that the metal oxide particles were directly adhered to the surface of the base material made of a metal material by polishing or the like, and the metal material was colored.

Further, an embodiment in which an aluminum alloy having a high reflectance and a difference in each of the above examples is used as a substrate has been described. However, from the above results, those skilled in the art should understand that when the substrate is a metal material other than an aluminum alloy, the same effects as described above can be obtained as long as metal oxide particles can be adhered to the surface.

The specific examples of the present invention have been described in detail above, but are merely exemplary and not intended to limit the scope of the patent claims. The technology described in the scope of the patent application includes various modifications and changes to the specific examples described above.

Claims (5)

An article having a metal oxide film, comprising: a base material made of a metal material; and a metal oxide film made of a metal oxide covering a surface of the base material, wherein the metal oxide film is transmitted through It is formed by polishing the surface of the base material using particles composed of the metal oxide. An article having a metal oxide film as claimed in claim 1, wherein the particles of the metal oxide have an average primary particle diameter of 10 nm or more and 1 μm or less. The article of claim 1 or 2, wherein the substrate is composed of a metal material having a Brinell hardness of 10 or more and 200 or less. The metal oxide film-attached article according to any one of claims 1 to 3, wherein the metal oxide particles comprise one or more selected from the group consisting of zirconia, cerium oxide and aluminum oxide. A metal oxide film-attached article according to any one of claims 1 to 4, wherein the substrate is aluminum or an aluminum alloy.