CN112020248B

CN112020248B - Anodized parts having a matte black appearance

Info

Publication number: CN112020248B
Application number: CN202010458199.8A
Authority: CN
Inventors: J·A·柯伦; A·D·帕特森; S·R·波斯塔克
Original assignee: Apple Inc
Current assignee: Apple Inc
Priority date: 2019-05-28
Filing date: 2020-05-26
Publication date: 2021-12-10
Anticipated expiration: 2040-05-26
Also published as: CN112020248A

Abstract

The present disclosure provides an anodized part having a matte black appearance. The anodized part includes a metal substrate and an anodized layer covering and formed from the metal substrate. The anodization layer includes: (i) an outer surface comprising randomly distributed light absorbing features capable of absorbing visible light incident on the outer surface; and (ii) a pore defined by pore walls, wherein the color particles are injected into the pore. The anodized layer is characterized as having a color with an L value of less than 10 using the CIE L a b color space.

Description

Anodized parts having a matte black appearance

Cross Reference to Related Applications

The present disclosure claims priority from us provisional patent application 62/853,629 entitled "ANODIZED PARTHAVING A MATTE BLACK ap pearant" filed on 28/5/2019, the entire disclosure of which is hereby incorporated by reference.

Technical Field

The embodiments generally relate to etching the surface of a dyed anodized part. More particularly, the embodiments relate to techniques for etching the surface of a dyed anodized part to form light absorbing features capable of absorbing substantially all visible light incident on the outer surface so as to impart a black appearance.

Background

Housings for portable electronic devices may include an anodized layer that may be colored in different colors to enhance its aesthetic appeal to consumers. However, some colors are much more difficult to implement than others. In particular, attempts by consumer electronics manufacturers to achieve a solid black color have not been successful. In fact, the best attempt only obtains dark gray. One challenge in achieving a solid black color is that the anodized metal can have a relatively high gloss that can specularly reflect a large amount of visible light.

Disclosure of Invention

According to some embodiments, an anodized part is described. The anodized part includes a metal substrate and an anodized layer covering and formed from the metal substrate. The anodized layer includes an outer surface including randomly distributed light absorbing features that absorb visible light incident on the outer surface and pores defined by pore walls, wherein color particles are injected into the pores, and the anodized layer has an L value using CIE L a b color space of less than 10.

In some embodiments, the outer surface of the anodized part includes a residual pit (scar) of 3 microns in diameter or greater. In another embodiment, a light absorbing feature that absorbs light incident to the outer surface, the light absorbing feature defined by a peak and a depression, and a top of the peak separated from a bottom of the depression by a gap distance of 2 microns or less. In some embodiments, the recesses of the anodized part have a diameter of less than 2 microns. In other embodiments, the peaks of the anodized part have different heights. In other embodiments, the pores of the anodized part are sealed. In some embodiments, the color particles comprise dye pigments or electrodeposited metals. According to another embodiment, the anodized layer has a gloss measured at 85 degrees of less than 10 gloss units.

According to some embodiments, a housing for a portable electronic device is described. The housing includes a substrate including a metal and an anodized layer covering the substrate. The anodized layer includes an outer surface having peaks of different heights separated by depressions of different depths, wherein the anodized layer is characterized as having a gloss appearance measured at 85 degrees of less than 10 gloss units, and a nanoscale tube having color particles infused therein.

According to some embodiments, the opening of the nanoscale tube is sealed. In some other embodiments of the housing, the top of the peak is separated from the bottom of an adjacent recess by a gap distance of 2 microns or less. In some embodiments, the depressions may have a diameter of 2 microns or less. In some embodiments, the housing is a heat dissipating component. In some embodiments, the anodized layer may have a L value less than 10 using the CIE L a b color space. In some embodiments, the color particles in the housing comprise a dye pigment or an electrodeposited metal.

According to some embodiments, a method for forming a case for a portable electronic device is described. The method includes forming an anodized layer overlying a metal substrate, injecting color particles into pores of the anodized layer, and forming light absorbing features on an outer surface of the anodized layer by etching the outer surface such that the anodized layer has a color with a value of L using the CIE L a b color space of less than 10.

According to some embodiments, the method for forming a housing for a portable electronic device includes sealing an aperture of an anodization layer prior to forming a light absorbing feature. In some embodiments, the light absorbing features are defined by peaks and valleys, and the tops of the peaks are separated from the bottoms of the valleys by a distance of 2 microns or less. The tops of the peaks may have different heights and the bottoms of the depressions have different depths. In some embodiments, the depressions have a diameter of less than 2 microns.

The present disclosure is provided merely for the purpose of summarizing some example embodiments so as to provide a basic understanding of some aspects of the subject matter described herein. Accordingly, it should be understood that the above-described features are merely examples and should not be construed to narrow the scope or spirit of the subject matter described in this disclosure in any way. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following detailed description, the accompanying drawings, and the claims.

Drawings

The present disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements.

Fig. 1 illustrates a perspective view of various portable electronic devices having housings that can be processed using the techniques described herein, according to some embodiments.

Fig. 2A-2B illustrate cross-sectional views of a process for forming an anodized part according to some embodiments.

Fig. 2C-2D illustrate cross-sectional views of a process for encapsulating anodized parts according to some embodiments.

Fig. 2E-2F illustrate cross-sectional views of a process for etching an anodized part according to some embodiments.

Fig. 3A-3B illustrate various views of a sealed anodized part prior to undergoing an etching process according to some embodiments.

Fig. 4A-4B illustrate various views of a sealed anodized part after undergoing an etching process according to some embodiments.

Fig. 5 illustrates a method for forming an anodized part having light absorbing features according to some embodiments.

Fig. 6A-6B illustrate exemplary images of anodized parts having light absorbing features according to some embodiments.

Fig. 7A-7B illustrate exemplary images of anodized parts having light absorbing features according to some embodiments.

Fig. 8 illustrates an exemplary graph representing gloss units as a function of etch time and L values using CIE L a b color space, according to some embodiments.

Detailed Description

Representative applications of the methods and apparatus according to the present disclosure are described in this section. These examples are provided merely to add context and aid in the understanding of the described embodiments. It will thus be apparent to one skilled in the art that the embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the embodiments. Other applications are possible, such that the following examples should not be considered limiting.

In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in accordance with the embodiments. While these embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, it is to be understood that these examples are not limiting; such that other embodiments may be used and modifications may be made without departing from the spirit and scope of the embodiments.

While housings formed from anodized metal can be colored in a variety of different colors, it is well known that coloring housings in certain colors, such as black, is difficult to achieve. Best attempts in the industry are only able to obtain dark grey. For example, depositing dye particles only within the pores of the anodized layer is not sufficient to impart a solid black color. In fact, the anodized layer reached a plateau of L values in the lower 20 seconds. A part of the challenge in achieving a solid black color is that the surfaces of these housings typically have a high gloss, which contributes to the specular reflection of a large amount of visible light.

Embodiments described herein set forth techniques for etching the outer surface of the anodization layer to form light absorbing features that absorb substantially all visible light incident on the outer surface. In addition, any visible light not absorbed by the light absorbing features is diffusely reflected by the outer surface. Thus, the outer surface is characterized as having a low gloss, matte finish.

As used herein, the terms anodic film, anodized film, anodic layer, anodized layer, anodic oxide coating, anodic layer, anodized layer, metal oxide layer, oxide film, oxide layer, and oxide layer may be used interchangeably where appropriate. In one example, the anodization layer can be produced by an electrochemical anodization process of aluminum or an aluminum alloy. As another example, the metal oxide layer may result from a deposition process. The metal substrate may comprise any of a variety of suitable metals or metal alloys thereof, such as aluminum, titanium, steel, and the like. It should be noted that the processes for forming the anodization layer and the metal oxide layer may be different. As used herein, the terms "component," "layer," "segment," and "portion" may also be used interchangeably, where appropriate.

According to some embodiments, an anodized part is described. The anodized part includes a metal substrate and an anodized layer covering and formed from the metal substrate. The anodized layer includes an outer surface including randomly distributed light absorbing features that absorb visible light incident on the outer surface and pores defined by pore walls, wherein color particles are injected into the pores, and the anodized layer has a L value less than 10 using the CIE L a b color space.

These and other embodiments are discussed below with reference to fig. 1-8. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be taken as limiting.

Fig. 1 illustrates various portable electronic devices that may be processed using the techniques described herein. The techniques described herein may be used to treat a metal surface of a housing of a portable electronic device. In some examples, the housing may include at least one of: a metal, metal alloy, polymer, or thermoplastic material. In some examples, the techniques described herein may be used to color a metal surface by causing color particles (e.g., water-soluble pigments, etc.) to be absorbed within the metal surface. In some examples, the techniques described herein may be used to seal the pore structure of the anodization layer to prevent external contaminants from reaching the underlying metal substrate via the pores. In addition, sealing the pore structure also prevents the dye particles from leaching from the anodized layer.

Fig. 1 shows an exemplary portable electronic device including a smartphone 102, a tablet computer 104, a smart watch 106, and a portable computer 108. These exemplary portable electronic devices are capable of using personally identifiable information associated with one or more users. It is well known that the use of personally identifiable information should comply with privacy policies and practices that are recognized as meeting or exceeding industry or government requirements for maintaining user privacy. In particular, personally identifiable information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use, and the nature of authorized use should be explicitly stated to the user.

According to some embodiments, an exemplary portable electronic device may include a housing that may benefit from absorbing substantially all visible light incident on an outer surface of the housing. For example, the smartphone 102 may include internal structures such as a camera housing, where it may be advantageous for the camera housing to have a colored black surface that absorbs substantially all visible light to prevent and/or minimize reflection of visible light that would otherwise affect the amount of light detected by the sensor of the camera. As another example, the housing of the portable computer 108 may serve as a heat sink, such as a heat sink, that is colored black to effectively draw in and dissipate heat generated by operating components (e.g., batteries, processors, etc.) carried within the portable computer 108. When the case colored black absorbs light, the case may convert the light into heat. Thus, implementing the techniques described herein for coloring the anodized layer to a solid black color may allow the enclosure to absorb a greater amount of energy and promote cooling from the interior. As described herein, pure black may refer to an L value of <10 or an L value of < 5.

One or more surfaces of the portable electronic device may exhibit any number of desired surface geometries and surface finishes. In some examples, the housing may include a three-dimensional structure having a height, a width, and a depth, as well as any type of geometry. Specifically, the housing is characterized as rectangular, polygonal, circular, beveled, angular, elliptical, and the like.

As will be described herein, the etched anodized surface of the housing having light trapping features (also referred to as light absorbing features) is capable of absorbing substantially all visible light incident thereon. In addition, any visible light not absorbed by the light trapping features is diffusely reflected by the light trapping features. Thus, the etched anodized parts are characterized by low gloss with a matte surface. The low gloss of the matte surface combined with the black particles injected into the pores can mask the outer surface geometry.

The anodized layer may have sufficient hardness such that the anodized layer functions as a protective coating that protects the metal substrate, for example, if these portable electronic devices are dropped, scratched, chipped, worn, or exposed to various corrosive contaminants. In some examples, the anodization layer includes a pore structure (also referred to herein as a nanotube) formed through a portion of the anodization layer. The pore structure extends from the outer surface of the anodized layer and terminates at the bottom/end surface. The anodized layer may be separated from the underlying metal substrate by a non-porous barrier layer.

The pore structure of the anodized layer is capable of receiving color particles that can impart a particular color to the anodized layer corresponding to the dye particles. Specifically, the anodized layer may be colored before sealing the anodized layer. For example, the anodized layer may be dyed to impart a wide range of colors to the anodized layer. In particular, the pore structure may have a diameter of about 20nm to about 40nm, which is large enough to receive the dye particle. Several parameters may influence and control the absorption of the dye particles into the pore structure, such as dye concentration, chemistry of the dye solution, pH of the dye solution, temperature of the dye solution, and dyeing time, as will be described in more detail herein. After dyeing the metal surface, the pore structure is sealed such that the dye particles are physically retained within the pore structure.

In some examples, the color of the anodized layer may be characterized according to CIE L a b color oppositance dimension values. The L × color opponent dimension value is a variable in L × a × b color space. Generally, L corresponds to brightness. L ═ 0 denotes extreme black, and L ═ 100 denotes white. Generally, a indicates the amount of red and green in the sample. Negative a values indicate green, while positive a values indicate red. Thus, a sample with a positive a-value would indicate that there is more red than green. Generally, b indicates the amount of blue and yellow in the sample. Negative b values indicate blue, while positive b values indicate yellow. Thus, a sample with a positive b value would indicate that there is more yellow than blue.

Fig. 2A-2B illustrate cross-sectional views of a process for forming an anodized part according to some embodiments. In some embodiments, the processed metal part 200 has a near net shape finished part, such as a housing of the portable

electronic devices

102, 104, 106, and 108.

Fig. 2A shows the metal part 200 prior to performing the anodization process. In some examples, the metal part 200 may correspond to the metal substrate 204. The metal substrate 204 may have any thickness suitable to provide sufficient strength, hardness, and rigidity to protect one or more electronic components carried within the portable electronic device and to protect fragile components of the housing (e.g., ceramic, glass, etc.). The metal substrate 204 may be subjected to one or more pre-anodization processes, such as at least one of polishing, sandblasting, buffering, cleaning, and the like.

Fig. 2B illustrates an anodized part 210 according to some embodiments. For example, the anodizing member 210 corresponds to the metal substrate 204 after being subjected to the anodizing process. As shown in fig. 2B, an anodization layer 206 is formed from the metal substrate 204 and covers the metal substrate 204. The anodization layer 206 can include an outer surface 202, and the outer surface 202 of the anodization layer 206 can be substantially parallel to a bottom surface 207 of the metal substrate 204. In some embodiments, the anodized layer 206 is formed as a result of an electrolytic anodization process. Specifically, during the electrolytic anodization process, a portion of the metal substrate 204 is converted or consumed by conversion to the anodization layer 206.

According to some embodiments, the thickness of the anodization layer 206 is between about 1 micron and about a few tens of microns. In some embodiments, the thickness is between about 5 microns and about 15 microns. The anodization layer 206 can be separated from the underlying metal substrate 204 by a non-porous barrier layer 208.

According to some embodiments, anodization layer 206 includes nanotubes 212 extending from outer surface 202 toward metal substrate 204. The nanotubes 212 may terminate at a terminal end 214 surface. The nanotubes 212 are defined by pore walls 216 that are characterized as having a generally cylindrical shape that is elongated in a direction generally perpendicular to a central plane of the outer surface 202 of the anodized part 210. The nanotubes 212 include openings 218 that can be sealed by a sealing process, as described in more detail herein.

Fig. 2C-2D illustrate cross-sectional views of a process for forming a colored sealed anodized part according to some embodiments. Fig. 2C shows the partial sealing member 220 after undergoing an optional coloring process according to some embodiments. In particular, fig. 2C shows that a portion of the sealing member 220 includes color particles 224 disposed/infused within the nanotubes 212. In some embodiments, the color particles 224 may be used in conjunction with the etching techniques described herein to impart a pure black color (e.g., L x <10) to the portion of the sealing member 220. In some embodiments, a solid black color may be achieved by dyeing a portion of the sealing member 220 with an organic water-soluble pigment. In other embodiments, a pure black color may be achieved by electrodepositing a metal (e.g., Co, Sn, etc.) into the nanotubes 212 via an electro-coloring process. Since the anodization layer 206 is highly porous, once the color particles 224 are deposited into the nanotubes 212, the nanotubes 212 should be sealed to permanently lock the color.

According to some embodiments, the color particles 224 may be distributed within the nanotubes 212 in a random distribution or a uniform distribution. Generally, there will be a higher concentration of color particles 224 near the outer ends of the nanotubes 212. However, high concentrations of colorant, extended tinting times, or high temperatures may minimize absorption of the color particles 224 and achieve a relatively uniform color throughout the anodized layer 206. During the coloring process, the color particles 224 bind to the locations of the pore walls 216.

Fig. 2C illustrates a partial sealing member 220 during a hydrothermal sealing process, according to some embodiments. In some embodiments, partially sealed part 220 represents anodized part 210 during the hydrothermal sealing process. According to some embodiments, after the coloring process, the anodized part 210 is exposed to a sealing solution. The sealing process involves the hydration of the amorphous alumina surface of the pore walls 216 to boehmite (Al)₂O₃.H₂O) and/or bayerite (Al)₂O₃.3H₂O) such that the amorphous aluminum material expands and closes the openings 218 of the nanotubes 212. The sealing process may be enhanced by using zinc acetate, which also precipitates metal hydroxides in the nanotubes 212 and speeds up the sealing process. In some embodiments, the hydrothermal sealing process may be performed in steam, hot water (e.g., at or near boiling temperature to reduce fouling), or at a temperature as low as about 70 ℃. The hydrothermal sealing process results in precipitation of hydrated alumina (e.g., boehmite, etc.). Specifically, the hydrothermal sealing process causes the aluminum oxide of the anodized layer 206 to expand when the anodized layer 206 is immersed in the sealing solution. The expansion of the alumina causes the opening 218 to narrow, thereby minimizing diffusion of external elements into the nanotube 212. The expansion of the opening 218 may also cause oxidized debris or metal oxide material to remain within the anodization layer 206. During the hydrothermal sealing process, the alumina (of aluminum oxide) is converted to a hydrated material 226, such as an alumina hydroxide (e.g., boehmite, diaspore, etc.), which causes the oxide surface to swell or increase in volume to partially close or partially seal the openings 218 of the nanotubes 212. In some embodiments, the hydrating material 226 uniformly lines the pore walls 216 of the nanotubes 212.

Fig. 2D shows the sealing member 230 after the completion of the hydrothermal sealing process. As a result of the hydrothermal sealing process, the opening 218 is sealed with a sealing member 232, such as a hydrated material 226 (e.g., boehmite, diaspore, etc.). The hydrothermal sealing process locks the color particles 224 into the nanotubes 212 and also protects the nanotubes 212 from dirt, grime, external contaminants, and the like. Color lock-in is important in the consumer electronics industry where uniform color between dyed parts and overall uniform appearance are considered highly attractive.

As shown in fig. 2D, the sealing member 230 includes nanotubes 212, the nanotubes 212 each having an equal or nearly equal length and diameter. As shown in FIG. 2D, the nanotube 212 is characterized as having a length (N) between the terminal surface 214 and the outer surface 202₁). Further, the nanotubes 212 may be characterized as having a substantially uniform height. Thus, the outer surface 202 may be characterized as having a general profileA flat surface.

Although sealing feature 230 contains color particles 224, it should be noted that the mere inclusion of color particles 224 within nanotubes 212 is not sufficient to impart a pure black color to anodized features (e.g., anodized feature 210, partially sealed feature 220, sealed feature 230, etc.). As used herein, the term "pure black" may refer to an anodized part having a color with an L value less than 10 using the CIE L a color space. Additionally, the term "solid black" may also refer to anodized parts that absorb about 99% or more of visible light. In fact, even if a fully saturated black dye is injected in the anodized part, the anodized part will have a minimum L value of at least about 25. Electrically coloring the anodized part can produce a slightly darker gray color having a minimum L value of at least about 20. In other words, in both cases, the use of dyeing and electro-coloring techniques makes the anodized part closer to dark gray. Thus, neither of these coloring techniques is sufficient to impart a solid black color to the anodized part. To achieve a solid black color, the anodized part (e.g., the sealing part 230) must be subjected to an etching process, as will be described herein.

Fig. 2E-2F illustrate cross-sectional views of a process for forming an etched anodized part according to some embodiments. In particular, fig. 2E shows the etched feature 250 after the etching process. The color particles 224 disposed within the nanotubes 212 and the hydrating material 226 including the seal 232 are generally not disturbed by the etching process. Thus, the anodized layer 206 of the etched part 250 remains sealed and includes approximately the same amount of color particles 224.

In contrast to the sealing member 230, the outer surface 202 of the etching member 250 is substantially non-planar due to the etching process. In particular, the etching process is associated with random etching of the walls 216 of the nanotubes 212, which results in the nanotubes 212 having different heights. The random etching of the pore walls 216 provides the outer surface 202 of the anodization layer 206 with an extremely fine surface texture. The etched surface texture produces depressions and peaks on the micrometer and submicron scale. In some embodiments, the depressions and peaks may also be referred to as valleys and peaks.

According to some embodiments, the sealing member 230 is etched by exposing the sealing member 230 to a phosphoric acid solution. In some embodiments, the sealing member 230 is exposed to the 85% phosphoric acid solution at a temperature of about 70 degrees celsius for about 15 seconds to 60 seconds. Those of ordinary skill in the art will appreciate that an etch time of more than 60 seconds will result in degradation of the seal 232, while an etch time of less than 15 seconds is insufficient to form the light absorbing features.

FIG. 2E shows anodized layer 206 including recesses (PT)_1-4) Each depression consisting of a Peak (PK)_1-4) Separated by a certain distance. Due to Peak (PK)_1-4) Have different heights, recesses (PT)_1-4) Have different depths, so the Peak (PK)_1-4) Top and recess (PT)_1-4) Are spaced apart by different distances. The separation distance is at least sufficient to cause diffuse reflection of substantially all visible light incident on the outer surface 202 that is not absorbed by the anodized layer 206. In one embodiment, the distance separating the top of a peak from the bottom of an adjacent recess may be a gap distance of about 2 microns or less. Indeed, it is well known in the art that the matte appearance is a direct result of the separation distance between the peaks and valleys. In particular, light incident on the outer surface 202 may cause diffusion of visible light when scattered at a variety of different angles rather than a single angle, as compared to specular reflection. In other words, the anodized layer 206 of the etched feature 250 can be characterized by a very low gloss appearance. Anodized layer 206 of etched feature 250 may have a matte appearance of less than 10 gloss units, as measured at 85 degrees. It should be noted that the use of anodized parts having a high gloss appearance does not achieve a pure black appearance because the outer surface of the high gloss anodized part specularly reflects a substantial portion of visible light. Thus, in some implementations, it may be necessary to etch the outer surface 202 of the anodization layer 206 to form depressions and peaks.

In addition, fig. 2E shows that the outer surface 202 of the anodized layer 206 includes at least one light absorbing feature (LA). Specifically, fig. 2E shows a light absorbing feature (LA)_1-4) Wherein the light absorbing features (LA)_1-4) Is formed by at least one recess (e.g., PT)₁) And at least one peak (e.g., PK)₁) And (4) limiting. For example, light absorbing features (LA)₁) Can be composed of (PT)₁) And (PK)₁) Definition, (LA)₂) Can be composed of (PT)₂) And (PK)₂) Definition, (LA)₃) Can be composed of (PT)₃) And (PK)₃) Is defined by, and (LA)₄) Can be composed of (PT)₄) And (PK)₄) And (4) limiting. The light absorbing features may be superimposed over substantially the entire outer surface 202. According to some embodiments, the light absorbing features may also be referred to as light capturing features. According to some embodiments, the depressions may also be referred to as valleys.

In some embodiments, the light absorbing features (LA) are capable of absorbing substantially all visible light (e.g., about 99% or more) incident on the outer surface 202. In particular, the light absorbing features (LA) may capture visible light therein. The use of light absorbing features (LA) causes the anodized layer 206 to absorb far more visible light than would otherwise be possible in a non-etched anodized part that includes only color particles. As shown in fig. 2E, the etched feature 250 includes light absorbing features (LAs) and color particles 224 that combine to give the etched feature 250 a solid black appearance. In some embodiments, the anodized layer 206 may be quantified as having a black appearance of extremely matte surfaces with a value of L of about 1, a value of about 0, and b value of about 0 using the CIE L a b color space.

Furthermore, the concave Part (PT)_1-4) Hefeng (PK)_1-4) The defined light absorbing features (LA) are also capable of diffusely reflecting substantially all visible light incident on the outer surface 202. Thus, the anodized layer 206 may be quantified as having gloss units measured at 20 degrees<1. Gloss units measured at 60 degrees<Gloss units measured at 1 and 85 degrees<10, extremely rough surface appearance. In addition, the anodized layer 206 may also be characterized as having a velvet appearance due to the diffuse reflective properties.

Fig. 2F illustrates a cross-sectional view of an etched feature 250 according to some embodiments. In particular, fig. 2F shows a random distribution of depressions (PT) and Peaks (PK) along outer surface 202 of anodization layer 206. Further, fig. 2F shows that between the etched outer surface of the etched member 250 and the non-etched outer surface of the sealing member 230Comparison of (1). For example, the first nanotube 252 is shown as having a length (N) from the outer surface 202₂). In addition, an amount of the pore walls 216 defining the first nanotube 252 are removed as a result of the etching process, such that a first etch amount (E) is removed relative to the non-etched outer surface₁). In addition, the second nanotube 254 is shown as having a length (N) from the outer surface 202₃). In addition, an amount of the pore walls 216 defining the second nanotubes 254 are removed as a result of the etching process, such that a second etch amount (E) is removed relative to the non-etched outer surfaces₂). Second etching amount (E)₂) Greater than the first etching amount (E)₁). Thus, the respective depressions and peaks of the first and

second nanotubes

252 and 254, respectively, have different depths and heights.

Fig. 3A-3B illustrate various views of sealing an anodized part according to some embodiments. In some embodiments, fig. 3A illustrates the seal member 230 of fig. 2D, and fig. 3B illustrates an enlarged cross-sectional perspective view of the seal member 230. As shown in fig. 3A, the sealing member 230 includes substantially cylindrical nanotubes 212 extending from the outer surface 202 to the metal substrate 204. After the anodization process, and prior to any machining, grinding, and/or polishing processes that modify the outer surface 202, the outer surface 202 of the seal member 230 may be characterized as substantially flat due to the nanotubes 212 having a substantially uniform length.

Fig. 3B illustrates an enlarged cross-sectional perspective view of a sealing member 230 according to some embodiments. As shown in fig. 3B, the opening 218 of the nanotube 212 is sealed with a seal 232. In some embodiments, the hydrating material 226 of the seal 232 may cover the color particles 224. In addition, the nanotubes 212 are separated by braided wires 302. Braided wire 302 may also be filled with hydrating material 226. Advantageously, the seal 232 extends to a depth of a few microns (e.g., between 3 microns and 5 microns) and is generally sufficient to prevent external contaminants from passing through the nanotubes 212 and reaching the metal substrate 204. Additionally, the seal 232 may also facilitate retention of the color particles 224 within the nanotubes 212.

The nanotubes 212 include color particles 224 that are infused therein to impart a predetermined color (such as dark gray, pink, blue, orange, red, etc.) to the sealed anodization layer 206. In some embodiments, the color particles 224 are organic water-soluble pigments or electrodeposited metals (e.g., Sn, Co, etc.). However, merely depositing color particles 224 having a black color within the nanotubes 212 is not sufficient to impart a solid black color to the anodization layer 206. To achieve a pure black color, the outer surface 202 of the anodized layer 206 is also subjected to an etching process to form light absorbing features.

Fig. 4A-4B illustrate various views of an etched anodized part according to some embodiments. In some embodiments, fig. 4A illustrates the etched feature 250 of fig. 2E-2F, and fig. 4B illustrates an enlarged cross-sectional view of the etched feature 250. As shown in fig. 4A, the etching component 250 includes substantially cylindrical nanotubes 212 extending from the outer surface 202 to the metal substrate 204. However, after the etching process, the outer surface 202 is textured (i.e., non-planar). Specifically, the nanotubes 212 are etched in a random manner such that Peaks (PK) and valleys (PT) are superimposed on the outer surface 202. Specifically, the Peaks (PK) and valleys (PT) correspond to nanotubes 212 having non-uniform lengths and/or non-uniform heights.

Fig. 4B illustrates an enlarged perspective view of an etched feature 250 according to some embodiments. As shown in fig. 4B, the opening 218 of the nanotube 212 remains sealed with a seal 232, wherein the seal 232 comprises a hydrating material 226 such as boehmite. In some embodiments, the nanotubes 212 of the sealing member 230 have a length between about 10 microns to about 20 microns. Where the etching process is such that at most about 10% of the length of the nanotubes 212 are etched or at most about 2 microns below the outer surface 202 of the sealing member 230, the seal 232 extends more than 2 microns below the outer surface 202. In some embodiments, the depressions (PT) may be separated from the tops of the Peaks (PK) and/or the outer surface 202 by about 2 microns. In other words, the seal 232 extends deeper than the degree of etching. In some embodiments, the outer region (e.g., outer surface 202) of the sealing member 230 is preferentially etched over the inner region. In some embodiments, the etching process is such that about 1 micron is etched from the outer surface 202. The depth of the etch may also depend on the duration of the etch process. It should be noted, however, that one of ordinary skill in the art would not extend the duration of the etching process at the risk of sacrificing the seal 232. In other words, the seal 232 should preferably remain intact after the etching process to prevent the color particles 224 from inadvertently leaching out of the nanotubes 212.

The etched features 250 are subjected to admittance testing, where admittance is a function of the seal chemistry. Specifically, the admittance (measured according to ASTM B457) corresponds to the electrochemical resistance of the anodized layer 206. Admittance testing involves performing electrochemical impedance spectroscopy at a fixed frequency (e.g., 1 kHz). Tests have shown that the admittance values of the sealing member 230 and the etching member 250 are substantially equal to each other; thus, the seal 232 is shown to remain intact. Other admittance tests indicate that the anodized layer 206 of the etched part 250 has an admittance value greater than 30micro Siemens, which further confirms that the seal 232 remains intact.

Fig. 4B also shows etching the nanotubes 212 after the etching process. In particular, the pore walls 216 of the nanotubes 212 may be etched such that the pore walls 216 have a textured surface capable of diffusely reflecting substantially all visible light. During the etching process, the inner region 402 of the pore wall 216 may etch more preferentially than the outer region 404 of the pore wall 216 due to the presence of the hydrated material 226 along the inner region 402. Despite preferential etching, about 90% or more of the anodized layer 206 remains after the etching process. In addition, the braided wires 302 may also be etched as a result of the etching process.

Fig. 4B shows that the depressions (PT) and the Peaks (PK) are formed on the entire outer surface 202 of the etching member 250. The combination of the depressions (PT) and Peaks (PK) may define light-absorbing features capable of absorbing substantially all visible light incident on exterior surface 202. In particular, the light absorbing features (LA) may capture visible light therein, and may also be referred to as light capturing features. The use of light absorbing features (LA) causes anodized layer 206 to absorb far more visible light than would otherwise be possible in a dyed or electrically colored non-etched anodized part.

According to some embodiments, each depression (PT) is characterized as having a substantially circular shape with a diameter of less than 2 microns. Furthermore, the recesses (PT) have bottoms that collectively define various depths of the nano-scale etched network. The depressions (PT) can be distinguished from craters (scratches) and pits (scratches) caused by sandblasting the outer surface 202. In particular, the pits are very shallow (i.e., <0.5 microns deep), and the pits have a diameter greater than 3 microns. However, since the pits are so large (i.e., larger than 3 μm), the pitch between adjacent pits is insufficient. Thus, the lack of a pitch means that the crater cannot absorb substantially all visible light incident on the outer surface 202 and diffusely reflect substantially all visible light. The residual pits and the pits do not have a substantially circular shape peculiar to the depressed Portion (PT). Furthermore, the grit blasting process does not produce the fine scale etching required to form the light absorbing features (LA).

The etched feature 250 includes light absorbing features (LAs) and color particles 224 that combine to give the etched feature 250 a solid black appearance. Thus, the anodized layer 206 may be quantified as having a black appearance of extremely matte surfaces using the CIE L a b color space with L values of about 1, a values of about 0, and b values of about 0. Furthermore, the light absorbing features (LA) defined by the valleys (PT) and Peaks (PK) are also capable of diffusely reflecting substantially all visible light incident on the outer surface 202. Thus, the anodized layer 206 can be quantified as having an extremely matte appearance with gloss units <1 measured at 20 degrees, gloss units <1 measured at 60 degrees, and gloss units <10 measured at 85 degrees.

Fig. 5 illustrates a method 500 for forming an etched anodized part having light absorbing features according to some embodiments. As shown in fig. 5, the method 500 may optionally begin at step 502, where the surface of a component (e.g., the metal substrate 204) is optionally treated. In some embodiments, the surface of the metal substrate 204 is subjected to a cleaning process, a texturing process, a buffing process, a sandblasting process, and/or a polishing process.

At step 504, an anodization process is performed on the metal substrate 204. During the anodization process, an anodization layer 206 is formed from the metal substrate 204. In some embodiments, the anodization layer 206 may be formed by exposure to a thermal oxidation process or an electrolytic anodization solution. After the anodization process, the electrolytic anodization solution may be rinsed from the outer surface 202 of the anodized layer 206 with deionized water and a buffer solution. Deionized water is used to stop the chemical reactions associated with the anodization process.

At step 506, the anodized layer 206 may optionally be colored as a result of a dyeing process or an electrical coloring process. During the dyeing process, anodized parts such as anodized part 210 are exposed to a water-soluble dye pigment in a dye solution bath. The anodized part 210 is immersed in the dye solution. Dye pigments are impregnated into the nanotubes 212 and adsorbed onto the pore walls 216. The dye solution may then be rinsed from the outer surface 202 of the anodized layer 206 with deionized water and a buffer solution. Deionized water is used to stop the chemical reactions associated with the dyeing process and to stabilize the dye pH. In the electro-coloring process, a metal (e.g., Co, Sn, etc.) may be electrodeposited into the nanotubes 212.

At step 508, the nanotubes 212 may optionally be sealed via a sealing process, according to some embodiments. In some cases, sealing the nanotubes 212 may be preferred because the seal 232 encloses the nanotubes 212 such that the color particles 224 remain within the anodization layer 206. The sealing solution may comprise a zinc salt (e.g., zinc acetate, etc.). The sealing solution may then be rinsed from the outer surface 202 of the anodized layer 206 with deionized water and subsequently dried.

At step 510, the outer surface 202 of the anodized layer 206 of the sealed part 230 may optionally be treated. For example, the anodized layer 206 may be subjected to surface polishing, surface blasting, or the like. It should be noted that treating the outer surface 202, such as by a grit blasting process, does not form light absorbing or light capturing features on the outer surface 202.

At step 512, the outer surface 202 of the sealing member 230 is subjected to an etching process. The etching process is associated with random etching of the walls 216 of the nanotubes 212, which results in nanotubes 212 having different heights. The random etching of the hole walls imparts an extremely fine surface texture to the outer surface 202 of the anodized layer 206. The etched surface texture produces depressions and peaks on the micrometer and submicron scale. According to some embodiments, the sealing member 230 is etched by exposing the sealing member 230 to a phosphoric acid solution. In some embodiments, the sealing member 230 is exposed to the 85% phosphoric acid solution at a temperature between about 65 degrees celsius and 70 degrees celsius for about 15 seconds to 30 seconds. Beyond 30 seconds, the seal 232 typically begins to degrade, while less than 15 seconds typically does not produce a sufficient amount of etching for forming the light absorbing features. It should be noted that etching the sealed anodized part represents a non-obvious departure from conventional anodization processes. Specifically, in the conventional process, etching is not performed after the sealing process because etching the sealing member 230 risks degrading the integrity of the sealing member 232. Further, etching the outer surface 202 of the seal member 230 also reduces the amount of hydrated material 226 that includes the seal 232; thereby reducing corrosion resistance. It should be noted, however, that the outer surface 202 after etching still exhibits some corrosion resistance because the seal 232 is still substantially present.

As a result of the etching process, the outer surface 202 of the anodized layer 206 includes at least one light absorbing feature (LA), wherein each of the light absorbing features (LA) is defined by at least one depression (PT) and at least one Peak (PK). The light absorbing features (LA) may generally be superimposed over the entire outer surface 202. In some embodiments, the light absorbing features (LA) are capable of absorbing substantially all visible light incident on the outer surface 202. In addition, any visible light not absorbed by the light absorbing features is diffusely reflected by the light absorbing features (LA).

Fig. 6A-6B illustrate exemplary electron microscope images of etched anodized parts according to some embodiments. Fig. 6A shows an etched anodized part 600 having an anodized layer 604 that includes an outer surface 602 having light absorbing features. In addition, the outer surface 602 includes dimples 610 produced by a grit blasting process.

Fig. 6B shows an enlarged view of position a. In particular, fig. 6B shows a plurality of depressions (PT) of light absorbing features randomly distributed across the entire outer surface 602. Further, fig. 6B shows that the pit 610 is significantly larger than the depression (PT). Further, the pit 610 is shallow (i.e., less than 0.5 microns), while the depression (PT) may be as deep as 2 microns.

Fig. 7A-7B illustrate exemplary electron microscope images of etched anodized parts according to some embodiments. Fig. 7A shows a network or forest of fine-scale depressions (PT) superimposed on the outer surface 702 of the anodized layer of an etched anodized part 700. As shown in fig. 7A, the depression (PT) is substantially circular in shape and less than 2 microns in diameter. The depression (PT) is formed by etching the walls 716 of the nanotube. The pore walls 716 define nanotube openings 718.

Fig. 7B shows an enlarged view of position B (also shown in fig. 7A) and demonstrates the extent of etching along the outer surface 702 and within the nanotube. Specifically, location B of fig. 7B shows a plurality of depressions (PT) and Peaks (PK) randomly distributed across the outer surface 702. The depressions (PT) and Peaks (PK) cause the outer surface 702 to diffusely reflect visible light incident thereon. In addition, the combination of depressions and peaks with color particles gives the anodized part 700a black appearance with an extremely matte finish using CIE L a b color space having a L value of about 1, a value of about 0, and b value of about 0.

In some embodiments, the reflectance spectrum of the anodized part may be measured for a range of wavelengths, such as 400 nanometers (nm) to 750nm or 400nm to 650 nm. In a specific embodiment, the reflectance spectrum of a conventional black anodized part in the range of 400nm to 740nm was measured using a Konica Minolta CM3700A spectrophotometer with diffuse illumination and 8 degree viewing angle. The average reflectivity of conventional anodized parts in this range was found to be 12.6%. The reflectance spectra in the range of 400nm to 740nm of exemplary parts prepared according to the process described herein (such as anodized part 700) were measured using the same spectrophotometer with diffuse illumination and 8 degree viewing angle. In this particular example, the part was found to have an average reflectivity of 1.7%. Furthermore, parts anodized according to the process described herein were found to have an average reflectivity of 0.17% over the range of 400nm to 650 nm. The CIE L a b colors of the conventional anodized parts were found to be 31.4 (L), 0.8 (a), and-1.7 (b), while the colors of the parts anodized according to the process described herein were found to be 1.5 (L), -0.0 (a), and-0.5 (b).

Fig. 8 illustrates an exemplary graph representing a relationship between gloss units and L-values as a function of etch duration, according to some embodiments. In some embodiments, the sealed anodized part had an initial L value of about 25 and a gloss appearance of 17 gloss units measured at 85 degrees prior to the etching process. As described herein, the light absorbing features require an etch duration of about at least 15 seconds. However, an etch duration of more than about 30 seconds may result in seal degradation.

As shown in the exemplary graph, after 15 seconds of etching, the etched anodized part had a value of L x of about 2 and 11 gloss units measured at 85 degrees. After 30 seconds of etching, the etched anodized part had a value of about 1 x L and 10 gloss units measured at 85 degrees. Aesthetically, the etched anodized part has a matte appearance because the outer surface of the etched anodized part diffusely scatters nearly all visible light.

Any range recited herein is inclusive of the endpoints. The terms "substantially", "substantially" and "about" are used herein to describe and account for small fluctuations. For example, they may refer to less than or equal to ± 5%, such as less than or equal to ± 2%, such as less than or equal to ± 1%, such as less than or equal to ± 0.5%, such as less than or equal to ± 0.1%.

Various aspects, embodiments, implementations, or features of the described embodiments may be used alone or in any combination. Various aspects of the described implementations may be implemented by software, hardware, or a combination of hardware and software. The embodiments may also be embodied as computer readable code on a non-transitory computer readable medium. The non-transitory computer readable medium is any data storage device that can store data which can thereafter be read by a computer system. Examples of non-transitory computer readable media include read-only memory, random-access memory, CD-ROMs, HDDs, DVDs, magnetic tapes, and optical data storage devices. The non-transitory computer readable medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Within the limits applicable to the present technology, the collection and use of data from a variety of sources may be used to improve the delivery of heuristic content or any other content to a user that may be of interest to the user. The present disclosure contemplates, in some instances, theseThe collected data may include personal information data that uniquely identifies or may be used to contact or locate a particular person. Such personal information data may include demographic data, location-based data, telephone numbers, email addresses, personal information, and/or personal information,

ID. A home address, data or records relating to the user's health or fitness level (e.g., vital sign measurements, medication information, exercise information), a date of birth, or any other identifying or personal information.

The present disclosure recognizes that the use of such personal information data in the disclosed technology may be useful to benefit a user. For example, the personal information data may be used to deliver target content that is of greater interest to the user. Thus, using such personal information data enables the user to have planned control over the delivered content. In addition, the present disclosure also contemplates other uses for which personal information data is beneficial to a user. For example, health and fitness data may be used to provide insight into the overall health condition of a user, or may be used as positive feedback for individuals using technology to pursue health goals.

The present disclosure contemplates that entities responsible for collecting, analyzing, disclosing, transmitting, storing, or otherwise using such personal information data will comply with established privacy policies and/or privacy practices. In particular, such entities should enforce and adhere to the use of privacy policies and practices that are recognized as meeting or exceeding industry or government requirements for maintaining privacy and security of personal information data. Such policies should be easily accessible to users and should be updated as data is collected and/or used. Personal information from the user should be collected for legitimate and legitimate uses by the entity and not shared or sold outside of these legitimate uses. Furthermore, such acquisition/sharing should be performed after receiving user informed consent. Furthermore, such entities should consider taking any necessary steps to defend and secure access to such personal information data, and to ensure that others who have access to the personal information data comply with their privacy policies and procedures. In addition, such entities may subject themselves to third party evaluations to prove compliance with widely accepted privacy policies and practices. In addition, policies and practices should be adjusted to the particular type of personal information data collected and/or accessed, and to applicable laws and standards including specific considerations of jurisdiction. For example, in the united states, the collection or acquisition of certain health data may be governed by federal and/or state laws, such as the health insurance association and accountability act (HIPAA); while other countries may have health data subject to other regulations and policies and should be treated accordingly. Therefore, different privacy practices should be maintained for different personal data types in each country.

Regardless of the foregoing, the present disclosure also contemplates embodiments in which a user selectively prevents use or access to personal information data. That is, the present disclosure contemplates that hardware elements and/or software elements may be provided to prevent or block access to such personal information data. For example, with respect to ad delivery services, the disclosed technology may be configured to allow a user to opt-in or opt-out of participating in the collection of personal information data at any time during or after registration services. In another example, the user may choose not to provide emotion-related data for the targeted content delivery service. In another example, the user may choose to limit the length of time that emotion-related data is kept, or to prohibit the development of the underlying emotional condition altogether. In addition to providing "opt-in" and "opt-out" options, the present disclosure contemplates providing notifications related to accessing or using personal information. For example, the user may be notified that their personal information data is to be accessed when the application is downloaded, and then be reminded again just before the personal information data is accessed by the application.

Further, it is an object of the present disclosure that personal information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use. Once the data is no longer needed, the risk can be minimized by limiting data collection and deleting data. In addition, and when applicable, including in certain health-related applications, data de-identification may be used to protect the privacy of the user. De-identification may be facilitated by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of stored data (e.g., collecting location data at a city level rather than at an address level), controlling how data is stored (e.g., aggregating data on a user), and/or other methods, as appropriate.

Thus, while the present disclosure broadly covers the use of personal information data to implement one or more of the various disclosed embodiments, the present disclosure also contemplates that various embodiments may be implemented without the need to access such personal information data. That is, various embodiments of the disclosed technology do not fail to function properly due to the lack of all or a portion of such personal information data. For example, content may be selected and delivered to a user by inferring preferences based on non-personal information data or an absolute minimum amount of personal information, such as content requested by a device associated with the user, other non-personal information available to a content delivery service, or publicly available information.

The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art that the embodiments may be practiced without the specific details. Thus, the foregoing descriptions of specific embodiments are presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the described embodiments to the precise form disclosed. It will be apparent to those skilled in the art that many modifications and variations are possible in light of the above teaching.

Claims

1. An anodized part comprising:

a metal substrate;

an anodized layer overlying and formed from the metal substrate, the anodized layer having an L value using CIE L a color space of less than 10;

wherein the anodization layer comprises:

an outer surface defining randomly distributed light absorbing features defined by peaks and valleys;

a well wall defining a plurality of wells; and

color particles injected into the plurality of pores.

2. The anodized part of claim 1, wherein the outer surface comprises residual pits having a diameter of 3 microns or greater.

3. The anodized part of claim 1, wherein:

the top of the peak is separated from the bottom of the depression by a gap distance of 2 microns or less.

4. The anodized part of claim 1, wherein the recesses have a diameter of less than 2 microns.

5. The anodized part of claim 1, wherein the peaks have different heights.

6. The anodized part of claim 1, wherein the plurality of pores are sealed.

7. The anodized part of claim 1, wherein the color particles comprise dye pigments or electrodeposited metals.

8. The anodized part of claim 1, wherein the anodized layer has a gloss measured at 85 degrees of less than 10 gloss units.

9. A case for a portable electronic device, the case comprising:

a substrate comprising a metal; and

an anodization layer covering the substrate, wherein the anodization layer includes:

a nanoscale tube;

color particles injected in the nano-scale tubes; and

an outer surface having peaks of different heights separated by depressions of different depths;

wherein the anodized layer has a gloss appearance measured at 85 degrees of less than 10 gloss units.

10. The housing of claim 9, wherein the opening of the nanoscale tube is sealed.

11. The housing of claim 9, wherein the tops of the peaks are separated from the bottoms of adjacent recesses by a gap distance of 2 microns or less.

12. The housing of claim 9, wherein the recess has a diameter of 2 microns or less.

13. The housing of claim 9, wherein the housing is a heat dissipating component.

14. The housing of claim 9, wherein the anodized layer has a L value less than 10 using CIEL a b color space.

15. The housing of claim 9, wherein the color particles comprise dye pigments or electrodeposited metals.

16. A method for forming a case for a portable electronic device, the method comprising:

forming an anodized layer covering the metal substrate;

injecting color particles into pores of the anodized layer; and

forming light absorbing features on the outer surface of the anodized layer by etching the outer surface such that the anodized layer has a color with an L value less than 10 using CIE L a b color space, wherein the light absorbing features are defined by peaks and valleys.

17. The method of claim 16, wherein:

the top of the peak is separated from the bottom of the depression by a distance of 2 microns or less.

18. The method of claim 16, wherein the tops of the peaks have different heights and the bottoms of the depressions have different depths.

19. The method of claim 16, wherein the depression has a diameter of less than 2 microns.

20. The method of claim 16, further comprising sealing the aperture of the anodization layer prior to forming the light absorbing feature.