TWI248479B - Aluminum product with film capable of varying color according to change of visual angle and method for forming film capable of varying color according to change of visual angle on aluminum basis metal base material - Google Patents

Abstract

This invention is related to an aluminum product with a film capable of varying colors according to changes of visual angles which comprises: an aluminum basis metal base material, an anodic oxidation film of aluminum capping the surface of such metal base material with its thickness less than 10 mum which includes a porous layer and a barrier layer and a metal deposition located in holes of the porous layer in which the metal deposition is obtained by using the alternation of direct current/alternating current or by means of concurrently using both to carry out electrolysis coloration. This invention is also related to a method for forming a film capable of varying colors according to changes of visual angles on an aluminum basis metal base material which comprises: carrying out anodic oxidation treatment on the aluminum basis metal base material to provide an anodic oxidation film of aluminum comprising a porous layer and a barrier layer with its thickness less than 10 mum and carrying out electrolysis coloration of anodic oxidation film of aluminum by using the alternation of direct current/alternating current or by means of concurrently using both on the metal deposition deposited in the holes of the porous layer.

Description

1248479

BACKGROUND OF THE INVENTION In recent years, due to the booming development of 3C industries such as computers, communications and consumer appliances, 3 C products have been decorated with aluminum-based metal substrates (for example, notebook computers, mobile phones, walkmans, and compact discs). The market demand for players 'MP3, cameras and personal digital aids (pDA), etc.) is increasing. The aluminum base metal substrate is not only lightweight but also has a metallic v feel, so it has gradually replaced the appearance parts of the painted paint. . The coloring of the aluminum base metal substrate is conventionally achieved by anodizing and electrolytically coloring the metal particles of the machine, which not only protects the metal substrate of the base from corrosion and scratches, but also provides an aesthetic decoration. The effect 'thinks the economic value of the base metal substrate. The anodizing treatment and electrolytic coloring of the base metal substrate are currently mature technology, generally in an electrolyte bath (such as a sulfuric acid bath or a phosphoric acid bath) using alternating direct current/alternating current or direct use of direct current or alternating current. Forming a layer of an anodized film on the base metal substrate, the oxide film comprising a porous layer (ie, an outer layer) and a barrier layer (ie, an inner layer), and then depositing inorganic metal particles in the pores of the porous layer, To give the aluminum base metal substrate a color appearance. However, the appearance color of the aluminum products obtained by the prior art is still a single color, and the color types are not many, mainly bronze, black and red. A known method of coloring an aluminum-based metal substrate can be found in, for example, the description of U.S. Patent No. 5,472,78, issued to Eliseo Benitez-Garriga, issued Dec. 5, 1995. Products and methods for electrolytically coloring anodized aluminum products, using traditional -4- paper scales applicable to China National Standard (CNS) A4 specifications (210 X 297 mm) 1248479 A7 B7 V. Description of invention (2) Sulfuric acid The bath/direct current method forms a layer of |g anodized film on the surface of the base metal substrate, the oxide film comprising a porous layer (ie, an outer layer) and a barrier layer (ie, an inner layer), followed by, for example, a direct current alternating current 4 Electrolytic coloring of an aluminum-based metal substrate is carried out by alternating currents of alternating current to alternating current of 4 direct currents. According to the embodiment provided in the U.S. patent specification, the thickness of the anodized film of the formed aluminum exceeds 15 μm, and the anodized film of the colored aluminum can only be caused by the optical interference effect. A color, which is an electrolytic coloring method, which does not produce a color change as the viewing angle changes. Because of this, it is emphasized in this U.S. patent that aluminum articles having various colors in the entire region of the visible light region can be produced, and the appearance of such aluminum products can only exhibit a single color. In response to the needs of the market and consumers, the industry is actively developing aluminum products with films that change color depending on the viewing angle, and can form a film that can change color depending on the viewing angle on the surface of the aluminum base metal substrate. Methods. BRIEF SUMMARY OF THE INVENTION The present invention provides a method for forming an aluminum PCZ' having a film which can be changed in color depending on a viewing angle, and a method for forming a film which can change color with a change in viewing angle on an aluminum base metal substrate, and a simple illustration of the drawing 1 represents the interference effect of the anodized film of aluminum formed by the method of the present invention. The anodized film of the present invention is formed by anodizing in a relatively acid bath, and has a total thickness of less than 10 μπ. Figure 2 represents the interference effect of the anodized film of aluminum formed by the method of the present invention.

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1248479

In another embodiment, the anodized film of aluminum is formed by an anodizing treatment sequence of a sulfuric acid bath-phosphoric acid bath-sulfuric acid bath. Fig. 3 is a view showing still another embodiment of the interference effect of the anodized film of aluminum formed by the method of the present invention, wherein the anodized film of aluminum is formed by an anodizing treatment sequence of a sulfuric acid bath-acid bath. Fig. 4 is a view showing still another embodiment of the interference effect of the anodized film of aluminum formed by the method of the present invention, wherein an anodized film of aluminum is formed by anodizing in a sulfuric acid bath under conditions of adjusting the voltage. The pattern of the symbol _ huihui element symbolizes the aluminum base metal substrate; 2 represents the metal deposit layer; 3 represents the micropores of the porous layer of the anodized film; '4 represents the barrier of the anodized film of aluminum Layer; 5 represents the surface of the metal deposit; 6, represents the surface of the base metal substrate; 7 represents the porous layer of the anodized film; 8 represents the small pores in the pores of the porous layer; A represents the incident light; B represents incident light; and d represents the thickness of the anodized film of aluminum. DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to provide an aluminum article having a film which can be changed in color depending on a viewing angle, and a method of forming a film which can change color depending on a viewing angle on an aluminum base metal substrate. The one of this Bog G is out of this temple 0 can be refined by the control of aluminum -6 -

1248479 A7 B7 V. INSTRUCTIONS (4) The thickness of the anodized film (ie, the interference layer) on the surface of the base metal substrate is within a specific range so as to cause different interference effects when the observer's viewing angle is changed. The color of the appearance of the aluminum base metal substrate is changed.

In particular, the present invention provides an aluminum article having a film that changes color with a change in viewing angle, comprising: - an aluminum base metal substrate, - a layer covering the surface of the metal substrate and having a thickness less than ΙΟμπι An anodized film of aluminum, the oxide film comprising a porous layer and a barrier layer, and - a metal deposit in the pores of the porous layer, wherein the metal deposit is alternated by direct current/alternating current or both The method is obtained by electrolytic coloring. The present invention further provides a method of forming a film that changes color with a viewing angle on an aluminum base metal substrate, comprising:

Wire-anodizing on an aluminum base metal substrate, β provides an anodized film comprising a porous layer and a barrier layer and having a thickness less than ΙΟμπι, and - by direct current/alternating current or both, A metal deposit is deposited in the pores of the porous layer to perform electrolytic coloration of the anodized film of aluminum. The term "film which can change color depending on the viewing angle" as used in the present invention means that the surface of the metal deposit contained in the film can interfere with the surface of the metal substrate of the underlying substrate under incident light. When the observer's perspective changes, it will behave differently. For the purposes of the present invention, the most important is the surface of the metal substrate on the base of the chain - 7 - This paper scale applies to the Chinese National Standard (CNS) Α 4 specification (210X 297 mm) 1248479 A7 &quot; -------- B7 V. Inventive Note (5) The thickness of the anodized film must be controlled to less than 1 Ο μηη. At this thickness, both the porous layer and the barrier layer are translucent or transparent, so that light absorption can be easily performed. With scattering, the desired interference color is produced. The base metal substrate of the collection may be any one of the skill in the art, preferably an aluminum alloy. The alloy of the known alloy often contains at least one additional metal element such as broken, magnesium, copper, zinc and iron. In addition to the thickness, the aluminum alloy, <purity is also an important factor that can affect whether the anodized film of the aluminum can be translucent or transparent. For example, if the aluminum alloy contains a large amount of stone and iron, an intermediate metal phase is formed and combined with the anodized film of aluminum to produce a misty film which does not produce the desired interference effect. Therefore, in the present invention, the aluminum alloy used in the aluminum alloy preferably has a purity of from 90.0 to 99.9%, preferably from 95.0 to 99.9%. In the present invention, an anodic oxidation treatment may be performed on an aluminum base metal substrate using any technique known in the art to form an anodic oxynitride film comprising a porous layer (outer layer) and a barrier layer (inner layer). For example, a sulfuric acid bath/direct current method taught in U.S. Patent No. 5,471,768 may be used, which may have a concentration from 5 to 40%, preferably from 1 to 2 k/() k degrees. Other acid baths (e.g., $ to 4% phosphoric acid) may be used or used as needed to form oxide films having different porous layer structures. The temperature of the anodizing treatment may be between 5 and 10 〇, preferably between 15 and 25 C. By controlling the voltage and treatment time of the anodizing treatment, Controlling the thickness of the anodized film of the formed aluminum. For example, the present invention can be used for anodizing treatment for a period of 0.5 to 30 minutes using a voltage between 0.5 and 50 volts. From 3 to -8 - This paper scale applies to the Chinese National Standard (CNS) A4 specification (210X 297 mm)

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1248479 V. Description of the invention (6 volts <private pressure treatment i to 15 minutes. In addition, the anodizing treatment t voltage has a shadow on the surface of the formed surface & oxide film structure. - Generally speaking, when the voltage is higher Large, the number of holes in the porous layer formed is small and the thickness of the pore wall is large, so the thickness of the barrier layer is also increased. Conversely, when the voltage is smaller, the number of pores formed in the porous layer is large and the thickness of the pore wall is small. In the normal anodizing process, if the applied voltage drops drastically, the outer layer of the pore layer is branched into a pore having a plurality of smaller pore sizes, which causes the anodized film of aluminum and the substrate. The bonding force between the two becomes weaker than in the present invention, and the thickness of the 1% electrode oxide film formed by the anode-based treatment on the aluminum base metal substrate is less than 1 〇p melon, and relatively speaking, the porous layer The thickness is greater than the barrier layer. Any of the electrolytic coloring techniques known in the art can be used in the present invention, with the proviso that it must be performed in an alternating current/direct current mode, as described in, for example, U.S. Patent No. 5,472,788. By way of example, an electroplating bath having the following composition may be used in the present invention: nickel sulfate having a concentration of from 15 to 50 g/liter, magnesium sulfate having a concentration of from 1 to 4 g/l, and concentration from 15 to 50.克 / liter of boric acid and ammonium sulphate from 5 to 30 g / liter, and using alternating current / direct current or both, using a voltage from 2 to 50 volts (preferably from 5 to 20 volts) to the porous Metal deposits are deposited in the pores of the layer. In the present invention, depending on the voltage employed, the electrolytic coloring may be carried out for a period of from 0.5 to 30 minutes (preferably i to 1 minute). Suitable metal deposits are It is known that it can be selected, for example, from the group consisting of steel 'iron, guar, nickel, tin, gold, silver, platinum, cadmium, lead, bell, and molybdenum. The thickness of the metal deposit also affects the interference formed. Color-9 - This paper scale applies to China National Standard (CNS) A4 specification (210 X 297 mm) 1248479 A.7 Factory ___ Β7___ V. Invention description (7) Type, therefore, in the present invention 'this metal The thickness of the deposit can be from 〇1 to 1 μιη, preferably from 〇·1 to 2 μ. In the present invention, the Applicant has found that when the thickness of the anodized film of aluminum is less than 1 Ο μηη (that is, when both the porous layer and the barrier layer are translucent or transparent), the DC/AC alternating or two are combined. At the same time, the electrolytic coloring method can cause at least two directional optical interference effects. The optical and interference effects are mainly caused by the interference and absorption of light reflected on the following two metal surfaces: (1) deposition on the porous layer The surface of the metal deposit in the pores' and (2) the surface of the aluminum base metal substrate located below the screen barrier layer, the interference color produced by the different incident light paths and different metal deposits difference. 1 to 4 respectively show different preferred embodiments of the present invention, in which the relationship between the structure of the interference layer and the type of electrolyte, the manner of formation, and the voltage used are discussed. ▲ Referring to Fig. 1 'the anodizing treatment using a sulfuric acid bath/direct current method' to form an anodized film comprising a porous layer 7 and a barrier layer 4 on an aluminum base metal substrate 1, the anodized film of aluminum The thickness d (i.e., the total thickness of the porous layer 7 and the barrier layer 4) is less than ΙΟμπι, and at this thickness, both the porous layer and the barrier layer are translucent or transparent. Metal 2 is then deposited at the bottom of the pores 3 in alternating current/alternating current or both for electrolytic coloration. The incident light a is reflected on the surface 6 of the aluminum base metal substrate, and the incident light b is reflected on the surface 5 of the metal deposit. The reflective surface and the optical path of the structure exhibit an interference effect of at least two color changes. -10- t paper size suitable for fiscal standards (CNS) A_4 specifications (2 said 97 public love 1

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1248479 -----_- B7 V. DESCRIPTION OF THE INVENTION (8) FIG. 2 shows another preferred embodiment of the present invention. In this embodiment, the first anodizing treatment is first performed by using a sulfuric acid bath/direct current method to form an anodized film of aluminum on the aluminum base metal substrate, followed by a phosphoric acid bath/direct current method. The secondary anodizing treatment increases the surface area of the pores in the porous layer, thus forming a pore structure having a narrow upper and lower width (similar to 缻4). Thereafter, electrolytic coloring is carried out by alternating current/alternating current or one of them simultaneously, and a metal such as nickel is deposited on the bottom of the pores to form a metal deposit. Subsequently, a third anodization treatment is carried out, and the front ruthenium metal deposit is translucent to facilitate the passage of the electrolyte during the first anodic oxidation treatment. This way, the surface area of the surface 5 of the metal deposit is increased to exhibit at least two different interference colors, and the thickness of the anodized film of the aluminum formed by the third/into-anodizing treatment also affects the interference effect. Figure 3 shows a further preferred embodiment of the invention. In this embodiment, the first anodizing treatment is first performed by using a sulfuric acid bath/direct current method to form an anodized film of aluminum on the aluminum base metal substrate, followed by a phosphoric acid bath/direct current method. A second anodizing treatment is performed, which can increase the pore structure of the bottom surface area of the pores in the layer of the pores, and thus the bottleneck. Thereafter, electrolytic coloring is performed by a combination of direct current/alternating current==, and a metal such as nickel is deposited on the bottom of the pores to form a metal deposit. The reflective surface and optical path of this structure can exhibit the interference effects of at least two color variations. As described above, in the normal anodizing process, if the applied voltage is suddenly lowered, the bottom of the pores of the porous layer is branched to become _·11

This paper size is applicable to the towel g g standard (CNS) Α 4 specifications (21〇 X 297 public) one Ϊ24Β479 A7 B7

There are several pores with smaller pore sizes, which makes the bonding force between the anodic oxide disk substrates of the Ming become weaker. Figure 4 shows the effect of this voltage change. In Fig. 4, an anodizing treatment is performed using a sulfuric acid bath/direct current method to form an anodized film. During the formation process, the voltage is gradually lowered to the bottom of each pore of the porous layer of the crucible, thereby forming a small number of branches. The pores 8 and the barrier layer 4 are also thinned. This results in the weakening of the bonding force between the barrier layer 4 and the metal substrate of the underlying substrate. The invention is easy to form the interference layer. The preferred embodiment is It is applied to the case where the formed structure is partially separated to change the color. The objects, features, and advantages of the present invention will become more apparent from the study of the embodiments. Example f Example 1 An aluminum alloy having an aluminum purity of 99.5% was subjected to an arrow treatment according to the following steps: first, 20% sodium pyrophosphate was used for degreasing treatment at 60 (for 3 minutes, washed with water, and then borrowed. Ultrasonic wave was applied to the above solution, degreased for 3 minutes, and then washed with water, and neutralized for 30 seconds with a nitric acid aqueous solution having a concentration of 3% by weight. This can form anodization of aluminum having a thickness of 5 μm on the aluminum alloy. a film comprising a porous layer and a barrier layer. The aluminum alloy treated by the above-mentioned ruthenium is anodized for 10 minutes at a temperature of ire in a sulfuric acid bath having a concentration of 丨2%, using a direct current voltage of 7 volts. Electrolytic coloring is carried out in the following manner: in a plating bath prepared in advance (the plating bath composition includes 25 g/liter of nickel sulfate, 2 g/l of magnesium sulfate, 25 g/l of boric acid and 5 g of lanthanum/liter of ammonium sulfate) , with a straight line of 4 volts - This paper scale applies to the Chinese National Standard (CNS) A4 specification (21〇x 297 DON)

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k 1248479 A7 B7 V. INSTRUCTIONS (10) The alternating current and the 9 volt alternating current are simultaneously combined and electrodeposited for 5 minutes to deposit metallic nickel on the bottom of the pores of the porous layer. After the electrolytic coloring was completed, the sealing was performed for 8 minutes with a hot nickel acetate sealing agent close to stagnation, and after sealing, the aluminum alloy was dried at 90 ° C for 20 minutes. The result is shown in Figure 1. Since the interference layer having a thickness smaller than ΙΟμπι was formed in Example 1, when the observation was made at different viewing angles, the surface of the aluminum alloy was caused to have at least two kinds of color changes due to the interference effect. Example 2 _ An aluminum alloy having an aluminum purity of 99.5% was pretreated in the same manner as in Example 1. The pretreated aluminum alloy was anodized for 10 minutes at a temperature of 15 ° C using a DC voltage of 7 volts in a sulfuric acid bath having a concentration of 12%. After washing with water, a second anodic oxidation treatment was carried out for 5 minutes at a temperature of 15 ° C in a phosphorous bath having a concentration of 12 volts using a direct current voltage of 7 volts. Then, electrolytic coloring is carried out in the following manner: · In the electroplating bath prepared in advance (the composition of the electroplating bath is the same as in the example 1), the electrolysis is performed by using a voltage of 12 volts in a manner of alternating current, alternating current, alternating current, alternating current, and alternating current, five times of alternating current. 5 minutes to deposit metallic nickel on the bottom of the pores of the porous layer. Then wash it again with water. Thereafter, a third anodizing treatment was carried out in a sulfuric acid bath under the same conditions as above. Then, the hole was washed with water close to boiling water, and after sealing, the aluminum alloy was dried at 90 ° C for 20 minutes. This can form an anodized film of aluminum having a thickness of 5 μm on the |g alloy, which comprises a porous layer and a barrier layer. The results are shown in Figure -13- This paper scale applies to the Chinese National Standard (CNS) Α4 specification (210Χ 297 mm) 1248479 A7 B7 5. The invention description (η) 2 is shown. Since the interference layer having a thickness smaller than ΙΟμιη was formed in Example 2, when the observer was at a different viewing angle, the surface of the aluminum alloy was caused to have at least two kinds of color changes due to the interference effect. Example 3 An aluminum alloy having an aluminum purity of 99.5% was subjected to the former method in the same manner as in Example 1. The pretreated aluminum alloy was anodized for 10 minutes at a temperature of 15 ° C using a DC voltage of 7. volt in a sulfuric acid bath having a concentration of 12 volts. After washing with water, a second anodic oxidation treatment was carried out for 5 minutes in a phosphoric acid bath having a concentration of 12% at a temperature of 15 ° C using a DC voltage of 12 volts. Electrolytic coloring is then carried out in the following manner: in a previously prepared electroplating bath (electroplating bath composition is the same as in Example 1), with a direct current -> alternating current direct current - alternating current - direct current five-time alternating current, using a voltage of 12 volts Electrodeposition was carried out for 5 minutes to deposit metallic nickel on the bottom of the pores of the porous layer. Then, the hole was washed with water close to boiling water, and after sealing, the aluminum alloy was dried at a temperature of 90 ° C for 20 minutes. This can form an anodized film with a thickness of 5 μm. The result is shown in Figure 3. Since the interference layer having a thickness of less than 10 μm was formed in Example 3, when the observer was at a different viewing angle, the aluminum alloy surface produced at least two kinds of color changes due to the interference effect. Example 4 The purity of aluminum was 9 9.5 °/. The aluminum alloy is made in the manner of Example 1. -14 - This paper scale applies to China National Standard (CNS) A4 specification (210 X 297 mm) 1248479 A7 B7 V. Invention description (12). The voltaic treatment is carried out with a DC voltage of 7 volts at a temperature of 15 ° C. The voltage drop speed, the voltage is gradually reduced to 0.5 volts and stays for 5 seconds, then the voltage is reduced to 0 volts, after staying for 5 seconds, the voltage is raised to 20 volts, staying for 20 seconds, v to obtain a branched shape Pore Structure. Then, electrolytic coloring is carried out in the following manner: in the electroplating bath prepared in advance (electroplating bath composition is the same as in the example 1), and the alternating current alternating current electric current alternating current five-time alternating current is used, and the electrode is electrodeposited for 5 minutes using a voltage of 12 volts. To deposit metallic nickel on the bottom of the pores of the porous layer. Then, the hole was washed with water close to boiling water, and after sealing, the aluminum alloy was dried at 90 ° C for 20 minutes. This can form an anodized film with a thickness of 5 μm on the alloy. The results are shown in Figure 4. ‘Because in Example 4, an interference layer having a thickness of less than 10 μηη was formed, and when the observer was at different viewing angles, the surface of the aluminum alloy produced at least two color changes due to interference effects. -15- This paper size applies to Chinese National Standard (CNS) Α4 specification (210 X 297 mm)

Claims (1)

12 Xie S^9i, 〇2438 Patent Application g Patent Scope Replacement (June 94) C8 Iiti range An aluminum article having a film that changes color with a change in viewing angle, comprising: - an aluminum base metal substrate, an anodized film covering the surface of the metal substrate and having a thickness smaller than that of the porous substrate, comprising a porous layer And a barrier layer, and - a metal deposit in the pores of the porous layer, which is produced by: - anodizing the aluminum base metal substrate to provide a porous layer and a barrier layer and having a thickness An anodized film of aluminum smaller than 丨〇μιη, and - by direct current/alternating alternating or both, depositing a metal deposit in the pores of the porous layer to perform electrolytic coloring of the anodized film of aluminum, wherein The anodizing treatment is carried out by a sulfuric acid bath/direct current method, the sulfuric acid bath system has a concentration of from 10 to 20% by weight, and (1) further anodizing treatment is further performed by a phosphorus defeat bath/direct current method. Forming a narrow and wide pore structure in the porous layer' or (2) further performing anodizing treatment by a phosphoric acid bath/direct current method to form in the porous layer The pore structure of the upper narrow width is 'subsequent' after electrolytic coloring, and then another anodizing treatment is performed by a sulfuric acid bath/direct current method; when the anodized film of aluminum is formed by a sulfuric acid bath/direct current method, the voltage is gradually decreased to 0 volts, so that a small number of branches are formed in the bottom of the pores in the porous layer; the plating bath contains nickel sulfate having a concentration of from 15 to 50 g/liter, and the concentration is from 1 〇. This paper scale applies to the Chinese National Standard (CNS) Α 4 Specification (210X297 mm) ABCD 1248479 VI. Patent application to 40 g/l of magnesium citrate, boric acid at a concentration of 15 to 5 g/l and ammonium sulfate at a concentration of 5 to 30 g/l; The treatment is carried out at a temperature from 5 to 丨〇〇〇c and at a voltage of from 5 to 5 volts for 5 to 3 minutes; and the metal of the metal deposit is selected from the group consisting of copper and iron. The group consisting of cobalt, nickel, tin, gold, silver, platinum, cadmium, lead, manganese, and molybdenum, and the thickness of the metal deposit is from 〇01 to 1 μιη. 2. According to the scope of the patent application! The article of the item, wherein the aluminum base metal substrate is an aluminum alloy containing from 90.0 to 99.9% aluminum. A method for forming a film which can change a color change depending on a viewing angle on an aluminum base metal substrate, comprising: encapsulating an aluminum base metal substrate to anodize to provide a porous layer and An anodized film of a barrier layer and having a thickness of less than 1〇4111, and - by direct current/alternating alternating current or a combination of both, depositing a metal deposit in the pores of the porous layer to perform an anodized film of aluminum Electrolytic coloring, wherein the anodizing treatment is carried out by a sulfuric acid bath/direct current method, and the sulfuric acid bath system has a concentration of from 10 to 20% by weight; when an anodized film of aluminum is formed by a sulfuric acid bath/direct current method, The voltage is gradually decreased to 〇volts to form a plurality of branched pores at the bottom of the pores in the porous layer; the method further comprises (1) performing an additional anodizing treatment by a phosphoric acid bath/direct current method to form an upper narrow in the porous layer Lower width pore structure, or (2) additional anodizing treatment by phosphoric acid bath/direct current method, applicable to China National Standard (CNS) A4 specification (210X) 297 mm) 2- A BCD 1248479 々, the patent application scope forms a narrow and wide pore structure in the porous layer, and then, after electrolytic coloring, another anodizing treatment is performed by a sulfuric acid bath/direct current method; The bath contains nickel sulfate at a concentration of from 15 to 5 g/l, a concentration of magnesium sulfate from i 〇 to 40 g/l, a boric acid concentration from 15 to 50 g/l, and a concentration from 5 to 30 g/l. Ammonium sulphate; the anodizing treatment is carried out at a temperature of 5 to 丨〇〇艽 and at a voltage of from 5 to 5 volts 〇. 5 to 30 minutes; and the metal system of the metal deposit is selected The group consisting of copper, iron, australis, nickel, tin, gold, silver, platinum, cadmium, lead, manganese, and molybdenum, and the thickness of the metal deposit is from 1 to 1 μm. 4. The method of claim 3, wherein the anodizing treatment is carried out at a temperature of from 15 to 25 ° C and at a voltage of from 3 to 20 volts for from 1 to 15 minutes. 5. The method according to item 3 of the patent application, wherein the electrolytic coloring &lt; electroplating bath comprises the following composition: nickel sulfate having a concentration of from 15 to 5 g/l, and magnesium sulfate having a concentration of from 10 to 40 g/l , concentration from 15 to 5 g / l &lt; boric acid and ammonium sulfate concentration from 5 to 30 g / l, using alternating current / direct current or both, using a voltage from 2 to 5 volts 0. 5 to 30 minutes. 6. The method of claim 5, wherein the electrolytic coloring is performed for 1 to 1 minute using a voltage of from 5 to 20 volts. -3-