JP2015045076A - Aluminum alloy sheet for beverage can body excellent in surface property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology allowing for prevention of false detection of an inspection machine in optical inspection of an aluminum alloy sheet used for a can body.SOLUTION: There is provided an aluminum alloy sheet for a can body excellent in surface property which has: a composition containing, by mass%, Si:0.40% or less, Fe:0.30% to 0.60%, Cu:0.15 to 0.50%, Mn:0.90 to 1.20%, Mg:1.00 to 1.70%, Cr:0.05% or less, Zn:0.30% or less, Ti:0.15% or less and the balance aluminum with inevitable impurities; and a brightness L* of 72.5 or more and a color difference value ΔE* of 0 to 1.5 measured by using a spectral colorimeter.

Description

  The present invention relates to an aluminum alloy plate for beverage can bodies having excellent surface characteristics such as color difference.

For the can body of the aluminum can, an Al—Mn—Mg based alloy hard plate such as JIS3004 (AA3004) or JIS3104 alloy is used. The alloy hard plate is required to have strength and corrosion resistance necessary for use as a container, a beautiful appearance, and excellent formability.
The alloy hard plate is manufactured through processes such as melting, casting, homogenization treatment, soaking treatment, hot rolling, cold rolling, and intermediate annealing, as in the case of a general aluminum alloy plate. Usually, the balance of strength and formability of each part of the can body is tempered to an optimum state. That is, the aluminum alloy plate is recrystallized once in the course of rolling to be in a soft state, and then cold-rolled with a reduction rate of about 50 to 90% to obtain an appropriate strength mainly by work hardening.

  Also, if the can is a two-piece can consisting of a lid (end) and a trunk (body), the body of the aluminum can is formed by punching a blank from an aluminum alloy plate for the can body and forming a large-diameter cup, A DI can is formed by a DI molding process combining (DRAWING) and ironing (IRONING). Then, the DI can opening trimming process, the cleaning process for removing lubricant and coolant, the outer surface painting / printing process and baking process, the inner coating and baking process, and the DI can opening necking and flange are performed. The can body is formed by the bending process.

The body of an aluminum can is painted, printed, or resin-coated, so the conventional aluminum alloy plate has been used for the purpose of solving problems such as the sharpness of painting and printing and the adhesiveness of the resin coating. A technique is known in which the surface roughness is defined, the absorbance ratio of the resin coated on the surface is defined, and the reflectance and color of the surface of the aluminum alloy plate are defined (see Patent Document 1).
In this technique, the surface roughness of the aluminum alloy plate is specified to be 0.5 μm or less, the infrared spectral absorbance ratio at different specific wavelengths in the coating resin is set to 0.9 or less, and the brightness L of the outer surface of the aluminum alloy plate is set. * Problem by reducing the saturation C * defined by c * = (a * 2 + b * 2) 1/2 that is 60 or more and L * a * b * color system chromaticity to less than 5. It has been solved.
In addition, after manufacturing the can body from an aluminum alloy plate, there is a technology that controls the reflectance of the plate surface for the purpose of preventing erroneous inspection in an inspection process in which an image is processed from an image taken with a CCD camera under illumination. It is known (see Patent Document 2).
In this technique, an average length RSm of a roughness curve in a 90 ° direction with respect to the rolling direction is 50 for an aluminum alloy plate made of an aluminum alloy in which the contents of Mn, Mg, Cu, Si, Fe, and Zn are defined. ˜150 μm, regular reflectance 35 to 50% in the rolling direction 0 °, regular reflectance 10 to 25% in the 90 ° direction, and ratio of the regular reflectance in these different directions to 3.2 or less. Prevents false inspections.

Japanese Patent No. 338137 JP 2008-274377 A

  The surface of the can body manufactured from the above-described aluminum alloy plate through various processes is optically inspected in the inspection process. For example, the flange portion, the inner surface of the can, and the bottom of the can are illuminated from the can mouth side with an illuminating device, photographed with an optical device such as a CCD camera, and inspected for dirt, foreign matter adhesion, cracking, surface properties and the like by image processing. In addition, an inspection machine may be introduced in each process during the molding of the can to inspect the surface of the alloy plate by image processing.

In order to inspect foreign objects by photographing the body of an aluminum can, the resolution of the inspection machine has been improved in order to increase the inspection accuracy of minute foreign objects and dirt, but especially on the surface of a glossy metal plate. In the inspection, although there is no foreign matter or dirt, the inspection machine erroneously detects it and determines that it is defective and discharges it.
As a result of investigating the cause of this false detection, in the inspection of a metal plate with a large surface gloss such as an aluminum alloy plate, the brightness difference and color difference partially increase in the reflected state of the illumination light, and there are defects such as foreign matter and dirt. It has been found that even if no defect occurs, it is determined as a defective product due to erroneous detection during image processing. For this reason, the present inventor arrived at the present invention in view of research on an aluminum alloy plate having a surface state in which an optical inspection machine does not cause the above-described erroneous detection.

  An object of this invention is to provide the technique which can prevent the misdetection of the inspection machine in the case of optically inspecting the aluminum alloy plate used for can bodies.

  The aluminum alloy plate for beverage can bodies having excellent surface characteristics according to the present invention is Si: 0.40% or less, Fe: 0.30% or more and 0.60% or less, Cu: 0.15 or more and 0.50% by mass%. Mn: 0.90 or more and 1.20% or less, Mg: 1.00 or more and 1.70% or less, Cr: 0.05% or less, Zn: 0.30% or less, Ti: 0.15% or less An aluminum alloy plate for a can body having a composition of the balance unavoidable impurities and aluminum, wherein the lightness L * of the surface measured using a spectrocolorimeter is 72.5 or more, and the color difference value ΔE between the coils * Is 0 to 1.5.

  The aluminum alloy plate for beverage can bodies having excellent surface characteristics according to the present invention is produced by hot rolling, cold rolling and intermediate annealing after obtaining an ingot from the molten aluminum alloy having the above composition, and is a finish plate for hot rolling. The thickness is in the range of 2.0 to 3.6 mm, the finished sheet thickness in the cold rolling is in the range of 0.20 to 0.27 mm, and the total cold rolling ratio after hot rolling is 86.5 to 94.4. % Range.

  The method for producing an aluminum alloy material for a can body of the present invention includes Si: 0.40% or less, Fe: 0.30% or more and 0.60% or less, Cu: 0.15 or more and 0.50% or less, in mass%. Mn: 0.90 to 1.20%, Mg: 1.00 to 1.70, Cr: 0.05% or less, Zn: 0.30% or less, Ti: 0.15% or less, An alloy ingot having the balance of inevitable impurities and aluminum is obtained by a hot rolling process to obtain an aluminum alloy hot rolled material having a finished sheet thickness of 2.0 to 3.6 mm, and then the total amount after hot rolling is obtained by a cold rolling process. The cold rolling rate is in the range of 86.5-94.4% and the finished plate thickness is 0.20 to 0.27 mm, and the surface brightness L * measured using a spectrocolorimeter is 72.5 or more, An aluminum alloy material having a color difference ΔE * between coils of 0 to 1.5 can be obtained. The features.

  According to the present invention, an aluminum alloy material for a can body having a surface brightness L * of 72.5 or more and a color difference value ΔE * between coils in the range of 0 to 1.5 can be obtained. When the optical inspection is performed by illuminating in FIG. 3, there is no erroneous detection of a non-defective product in the inspection process, and the inspection accuracy is improved.

Hereinafter, although the manufacturing method of the aluminum alloy plate for can bodies which is excellent in the surface characteristic which concerns on this invention is demonstrated, the board thickness, alloy composition, and surface characteristic of the aluminum alloy plate for can bodies are demonstrated first.
The aluminum alloy plate for can bodies of this embodiment has a target plate thickness of 0.20 mm or more and 0.27 mm or less, and by mass%, Si: 0.40% or less, Fe: 0.30% or more and 0.60. %: Cu: 0.15 or more and 0.50% or less, Mn: 0.90 or more and 1.20% or less, Mg: 1.00 or more and 1.70% or less, Cr: 0.05% or less, Zn: 0 .30% or less, Ti: 0.15% or less, and the balance is made of an aluminum alloy having a composition of inevitable impurities and aluminum.
Moreover, the aluminum alloy plate for can bodies of this embodiment obtains an aluminum alloy hot-rolled sheet having a finished sheet thickness of 2.0 to 3.6 mm by performing a hot rolling process on an ingot made of an aluminum alloy having the above composition range. Then, the finished sheet thickness is 0.20 to 0.27 mm by a cold rolling process, and the total cold rolling rate after hot rolling is manufactured in the range of 86.5 to 94.4%. In addition, the aluminum alloy plate for a can body of the present embodiment obtained after cold rolling has a surface brightness L * measured by using a spectrocolorimeter of 72.5 or more, and a color difference value ΔE * between coils is It is the range of 0-1.5 (0 or more and 1.5 or less).

[Ingredient composition]
Hereinafter, the component composition limited in the aluminum alloy plate for can bodies excellent in the surface characteristics of this embodiment will be described. In addition, content of each element described in this specification is mass% unless otherwise specified, and the description of the range includes an upper limit and a lower limit unless otherwise specified. Therefore, for example, the notation of 0.35 to 0.55% means 0.35% or more and 0.55% or less.

“Si” 0.40% or less Si forms a compound with Mg and the like contained at the same time in the aluminum alloy plate for can bodies having excellent surface characteristics of the present embodiment, and improves the strength by precipitation hardening and dispersion hardening action. In addition, it is contained in an Al—Mn—Fe intermetallic compound, and has an effect of preventing seizure against a die during ironing.
If the Si content exceeds 0.40%, the strength becomes too high, and when a can body is produced, it becomes easy to cause a cylinder to be cut and the workability deteriorates.
If the Si content exceeds 0.40%, the amount of Al-Mn-Fe intermetallic compounds increases, and further, intermetallic compounds with Mg, Cu, and Al cannot be solutionized, and the toughness is increased. The pinhole is likely to occur. Accordingly, the Si content is preferably within the range of 0.40% or less, but if it is too small, it is difficult to obtain sufficient strength, so the range of 0.2% to 0.40% is more preferable. .

"Fe" 0.30-0.60%
In the aluminum alloy plate for can bodies having excellent surface characteristics according to the present embodiment, Fe increases the amount of the Al—Mn—Fe intermetallic compound, so that the crystal is refined and seized against the die during the ironing process. It has the effect of preventing the occurrence.
When the Fe content is less than 0.30%, the amount of the Al—Mn—Fe-based intermetallic compound is too small, and seizure to the ironing mold is likely to occur. When the Fe content exceeds 0.60%, the amount of Al—Mn—Fe intermetallic compound is excessively increased, workability is deteriorated due to a decrease in toughness, and pinholes are easily generated. Therefore, the Fe content is preferably in the range of 0.30 to 0.60%.

"Cu" 0.15-0.50%
Cu forms an intermetallic compound with Mg and the like in the aluminum alloy plate for can bodies excellent in surface characteristics of this embodiment, and has an effect of increasing strength by solid solution hardening, precipitation hardening, and dispersion hardening.
If the Cu content is less than 0.15%, a sufficient strength improvement effect cannot be obtained. If the Cu content exceeds 0.50%, side cracks are likely to occur, the rolling property is lowered, the strength is too high, and the body is likely to be cut when it is manufactured as a can body. In addition, the intermetallic compound with Mg, Si, and Al cannot be in solution, and the workability deteriorates due to a decrease in toughness, and pinholes are likely to occur. Therefore, the Cu content is preferably in the range of 0.15 to 0.50%.

“Mn” 0.90 to 1.20%
Mn forms an Al-Mn-Fe intermetallic compound in the aluminum alloy plate for can bodies having excellent surface characteristics according to the present embodiment, exhibits a dispersion hardening action as a crystallization phase and a dispersed phase, and irons It has the effect of preventing seizure from occurring on the die during molding.
If the content of Mn is less than 0.90%, the amount of Al—Mn—Fe intermetallic compound becomes too small to obtain sufficient curing characteristics, and seizure to the ironing mold is likely to occur. . When the content of Mn exceeds 1.20%, the amount of Al—Mn—Fe intermetallic compound becomes too large, workability deteriorates due to a decrease in toughness, and pinholes are likely to occur. Therefore, the Mn content is preferably in the range of 0.90 to 1.20%.

"Mg" 1.00 to 1.70%
Mg has a solid solution strengthening action in the aluminum alloy plate for can bodies excellent in the surface characteristics of the present embodiment, enhances work hardenability at the time of rolling, and coexists with Si and Cu to achieve dispersion hardening and precipitation hardening action. To improve the strength.
If the Mg content is less than 1.00%, sufficient strength cannot be obtained. If the Mg content exceeds 1.70%, side cracks are likely to occur, the rollability is lowered, the strength is too high, the workability is lowered, and the can body is cut when it is made as a can body. And cracking of the flange portion is likely to occur. Therefore, the Mg content is preferably in the range of 1.00 to 1.70%.

“Cr” 0.05% or less Cr exhibits the effect of reducing the size of precipitates and preventing seizure on the die during ironing. If the Cr content exceeds 0.05%, it becomes brittle and the workability tends to deteriorate. Therefore, the Cr content is preferably 0.05% or less. In addition, in order to acquire the above-mentioned effect, it is preferable to contain 0.001% or more of Cr.
“Zn and Ti” Zn: 0.30% or less, Ti: 0.15% or less The aluminum alloy plate for a can body having excellent surface characteristics according to this embodiment is Zn: 0.30% or less, Ti: 0% by mass. The component composition may contain 15% or less.
Zn has the effect of refining the precipitated intermetallic compounds of Mg, Si, and Cu, but when it contains Zn, used aluminum cans (UBC) and recycled materials can be effectively used as raw materials. If the Zn content exceeds 0.30%, the corrosion resistance tends to deteriorate.
In the aluminum alloy plate for can bodies having excellent surface characteristics according to the present embodiment, Ti has an effect of refining crystal grains and improving workability. When the Ti content exceeds 0.15%, the amount of intermetallic compounds increases so much that the toughness decreases and pinholes are likely to occur. Therefore, the Ti content is preferably 0.15% or less.
Further, the aluminum alloy plate used in the present embodiment may contain 0.05% or less of other elements as impurities.

"Production method of aluminum alloy sheet"
The aluminum alloy plate for a can body according to the present invention is manufactured through ordinary melting, casting, homogenizing treatment, soaking treatment, hot rolling, and cold rolling applied when manufacturing this type of aluminum alloy. . Moreover, between passes of cold rolling, annealing by a box-type annealing furnace heated to a temperature of 300 ° C. or higher and 500 ° C. or lower for 1 hour or more, or by a continuous annealing furnace heated to a temperature of 400 ° C. or higher and 600 ° C. or lower for 1 second or longer It is preferable to perform annealing. Further, this annealing may be performed in two or more times.

"Hot rolling"
In hot rolling, after melting, casting, homogenizing treatment, soaking treatment, slabs taken out from the furnace are put in and hot rolling is started, but while the rolled material is thick, there is usually a transport table before and after the rolling mill. Rolling is performed using a single stand reversible hot roughing mill installed, and rolling is performed with a hot finish rolling mill when the thickness of the rolled material is reduced to some extent. The hot finish rolling mill includes a reversible single type in which winding devices are installed before and after the rolling mill, and a non-reversible tandem type in which three to four sets of rolling rolls are arranged in series. And the plate | board thickness after hot finish rolling needs to be 2.0 mm or more and 3.6 mm or less. When the plate thickness is too thin or the plate thickness is too large, there arises a problem that the target final plate thickness cannot be realized by the target total cold rolling rate in the cold rolling described later.
On the other hand, when the thickness of the hot rolled sheet exceeds 3.6 mm, the coil temperature immediately after winding after the final hot rolling pass becomes high, and the oxidation of the sheet surface becomes remarkable immediately after hot rolling and in the subsequent cooling process. This oxide film is divided by cold rolling subsequent to hot rolling. When the thickness of the hot rolled plate exceeds 3.6 mm, the brightness when the final plate surface is measured using a spectrocolorimeter. L * value is less than 72.5. In this case, when an engineering inspection is performed by applying illumination light in a later inspection process, the detection is dark and the false detection tends to increase, and it is difficult to achieve the object of the present application.

"Cold rolling"
After cooling after hot pressing, cold rolling is performed at a total cold rolling rate of 86.5% or more and 94.4% or less. As a result of the study by the present inventors, when the thickness after the final cold rolling is 0.20 mm or more and 0.27 mm or less, the thickness by hot finish rolling described above is in the range of 2.0 or more and 3.6 mm or less. By doing this, a total cold rolling reduction of 86.5% or more and 94.4% or less can be obtained. By setting the total cold rolling rate in the range of 86.5% or more and 94.4% or less, the degree of division of the oxide film formed on the surface immediately after hot rolling and in the subsequent cooling process is within a certain range. Can fit. For this reason, the value ΔE * of the color difference between the coils when the surface of the final aluminum alloy plate is measured using a spectrocolorimeter may be in the range of 0 to 1.5 (0 to 1.5). It becomes possible. When the total cold rolling rate of the aluminum alloy sheet is less than 86.5%, 94, and 4%, the color difference value ΔE * between the coils is in the range of 0 to 1.5 (0 to 1.5). The detection error tends to increase when an optical inspection is performed by illuminating illumination light in a later inspection process, making it difficult to achieve the object of the present application.
When the total cold rolling rate is less than 86.5%, the L * value is less than 72.5, and it is difficult to achieve the object of the present subject.

"Thickness of aluminum alloy sheet for can body"
The plate thickness of the aluminum alloy plate for can bodies that is finally excellent in surface characteristics according to the present embodiment is in the range of 0.200 mm to 0.270 mm.
When the plate thickness is less than 0.200 mm, it becomes difficult to obtain sufficient pressure resistance when canned to form a can body. On the other hand, if the plate thickness exceeds 0.270 mm, the weight of the bottom of the can body becomes heavy, which increases the manufacturing cost and is not economical.
The thickness of the aluminum alloy plate for can bodies having excellent surface characteristics according to this embodiment is more preferably in the range of 0.230 mm to 0.270 mm.

According to the hot rolling process and the cold rolling process described above, the surface lightness L * measured using a spectrocolorimeter is 72.5 by manufacturing an aluminum alloy plate made of an aluminum alloy having the composition ratio described above. With the above, an aluminum alloy plate having a color difference value ΔE * between coils in the range of 0 to 1.5 (0 or more and 1.5 or less) can be obtained.
Thus, if the surface lightness L * is 72.5 or more and the color difference value ΔE * between coils is 0 to 1.5, the aluminum alloy plate has sufficient lightness and sufficiently small color difference. In the inspection process in which the illumination light is applied to the surface of the alloy plate and the defect is detected by reading the image, the inspection machine is less likely to make a false detection, and the inspection accuracy can be improved. That is, the surface of the aluminum alloy plate has lightness, so that it is not mistakenly detected as a surface stain or irregularities in the surface, and the color difference is small, so that the color difference in reflected light from the surface of the aluminum alloy plate is small. Color variation due to color unevenness and non-uniformity caused by the surface is small, and when the reflected light is image-analyzed, there are fewer false detections that determine that a good aluminum alloy plate without defects such as scratches and irregularities is defective. .

Moreover, about the obtained aluminum alloy plate, since it is normally baked after being processed into a can body, it has a proof strength of about 230 to 320 N / mm ² as a proof strength after heat treatment at 200 to 220 ° C. Is desirable.

EXAMPLES Hereinafter, although an Example is shown and the manufacturing method of the board | plate material for high-strength can bodies with the favorable surface property based on this invention is demonstrated in detail, this invention is not limited to a following example.
Al-0.31% Si-0.44% Fe-0.39% Cu-0.99% Mn-1.35% Mg-0.02% Cr-0.14% Zn-0.04% Ti The aluminum alloy having the composition was melted, degassed and filtered with a molten metal, and then cast into a slab having a thickness of 600 mm, a width of 1500 mm, and a length of 4.5 m by semi-continuous casting.
Next, the slab was homogenized at 565 ° C., and then hot-rolled to a sheet thickness of 3.20 or 3.19 mm, and then cold-rolled to a sheet thickness of 0.70 mm. And the continuous annealing (IA-CAL) which heats to the temperature range of 480 degreeC-590 degreeC for 1 s-60 s is given, and also it cold-rolls to the final sheet thickness of 0.252 mm, and the sample of Examples 1-11 of Table 1 is carried out. Obtained.
The thickness of the hot-rolled finished sheet, the total cold rolling rate after hot rolling (%), whether or not pre-treatment under the same conditions as cleaning / etching after can-making, and abnormal discharge in a can surface inspection machine Measured and listed in Table 1 below, and the color characteristic results of the resulting aluminum alloy sheet are listed in Table 2. The lightness L * and the color difference value ΔE * are also shown in Table 1.

The color difference value ΔE * was measured using a spectrocolorimeter CM-508d manufactured by Minolta Co., Ltd. The measurement is performed under the first light source: D65 and a visual field of 10 ° under measurement conditions. The L * a * b * color system is a display method defined in JIS Z 8729 and is based on the color difference display method of JIS Z 8730. The color difference value ΔE * is known as an NBS unit determined by the US National Bureau of Standards. 0 to 0.5, 0.5 to 1.5, 1.5 to 3.0, 3.0 to 6.0, 6 It is an index that is ranked as 0 to 12, 12 or more.
Color difference values (ΔE *) are ranked in NBS units (US National Bureau of Standards) as shown in Table 3 below.

  In Tables 1 and 2, “with pretreatment (chemical conversion treatment)” means that chemical removal treatment is carried out with a zirconium phosphate-based treatment solution to remove those that cannot be removed by washing and to improve coating film adhesion after canning. The sample was shown. In Table 1 and Table 2, the sample subjected to the chemical conversion treatment and the sample not subjected to the chemical conversion are written together to grasp whether the change in the surface state due to the chemical conversion treatment affects the value of ΔE * of the surface. Because.

"Comparative example"
Comparative Examples 1-3 and 5-7 are Al-0.29% Si-0.41% Fe-0.38% Cu-0.98% Mn-1.34% Mg-0.02% Cr-0. Aluminum alloy having a composition of 15% Zn-0.04% Ti, Comparative Example 4 is Al-0.29% Si-0.40% Fe-0.25% Cu-0.98% Mn-1.21% Mg An aluminum alloy having a composition of -0.02% Cr-0.17% Zn-0.03% Ti was melted, and an aluminum alloy plate was manufactured through structural steps similar to those of the previous examples. The hot rolled finished sheet thicknesses of Comparative Examples 1 to 3 and Comparative Examples 5 to 7 are 5.43 mm, the total cold rolling rate after hot rolling is 95.36%, and the hot rolled finished sheet thickness of Comparative Example 4 is The total cold rolling ratio after hot rolling at 2.60 mm is 84.62%.

The can surface inspection machine shown in Table 1 is a dedicated inspection system that detects defects with high speed and high accuracy by combining, for example, LED lighting manufactured by Kurashiki Boseki Co., Ltd. and a high-precision CCD camera. Analyzes the surface image and detects defects. The abnormal discharge at this time means that the inspection machine erroneously detects and discharges the cans in a concentrated manner even though there is no foreign matter or dirt.
The values of ΔL *, Δa *, and Δb * shown in Table 2 are values calculated based on each value indicated by the reference sample.

  From the results shown in Tables 1 and 2, Examples 1 to 3 were hot-rolled finished sheet thicknesses of 3.20 or 3.19 mm, and the total cold rolling rate after hot rolling was 92.13 or 92.10%. In any of the 11 samples, the lightness L * was in the range of 73.10 to 74.36, and the color difference ΔE * was in the range of 0.10 to 0.92. That is, it was within the range of L * 72.5 or more and ΔE * = 0 to 1.5 defined in the present invention. For this reason, abnormal discharge did not occur in the can surface inspection machine.

On the other hand, the samples of Comparative Examples 1 to 3 and 5 to 7 in which the hot rolled finish plate thickness exceeds 3.6 mm and the total cold rolling rate after hot rolling exceeds 94.4%, As for the sample of the comparative example 4 in which the total cold rolling rate after hot rolling is less than 86.5%, L * value is less than the range of 71.31 to 72.45 and 72.5, and ΔE * value is The range of 1.81 to 2.61 and 1.5 were exceeded, and even when an aluminum alloy plate having no defects was inspected, it was found that the inspection machine on the surface of the can erroneously detected and abnormally discharged.
In addition, no significant difference was observed between the sample whose surface was cleaned by chemical conversion treatment and the sample which was not subjected to chemical conversion treatment. Therefore, according to the aluminum alloy plate of the present embodiment, it is possible to obtain a feature that is unlikely to cause an erroneous inspection with an optical inspection machine regardless of whether or not the surface is subjected to chemical conversion treatment.

Claims (3)

  In mass%, Si: 0.40% or less, Fe: 0.30% or more and 0.60% or less, Cu: 0.15 or more and 0.50% or less, Mn: 0.90 or more and 1.20% or less, Mg: Aluminum alloy for can body containing 1.00 or more and 1.70 or less, Cr: 0.05% or less, Zn: 0.30% or less, Ti: 0.15% or less and having the balance of inevitable impurities and aluminum Beverage can excellent in surface characteristics, characterized in that the surface brightness L * measured using a spectrocolorimeter is 72.5 or more and the color difference value ΔE * is 0 to 1.5. Aluminum alloy plate for the body.   After obtaining an ingot from the molten aluminum alloy having the above composition, it is produced by hot rolling, cold rolling, and intermediate annealing, and the finished sheet thickness of hot rolling is in the range of 2.0 to 3.6 mm. The finished sheet thickness is in the range of 0.2 to 0.27 mm, and the total cold rolling ratio after hot rolling is in the range of 86.5 to 94.4%. Aluminum plate for beverage can bodies with excellent surface characteristics.   In mass%, Si: 0.40% or less, Fe: 0.30% or more and 0.60% or less, Cu: 0.15 or more and 0.50% or less, Mn: 0.90 or more and 1.20% or less, Mg: An alloy ingot containing 1.00 or more and 1.70% or less, Cr: 0.05% or less, Zn: 0.30% or less, Ti: 0.15% or less, and having the balance of inevitable impurities and aluminum An aluminum alloy hot rolled material having a finished sheet thickness of 2.0 to 3.6 mm is obtained by a hot rolling process, and then the total cold rolling ratio after hot rolling is 86.5 to 94.4% by a cold rolling process. The finished plate thickness is 0.20 to 0.27 mm, the surface brightness L * measured using a spectrocolorimeter is 72.5 or more, and the color difference value ΔE * is 0 to 1.5. Aluminum for beverage can bodies with excellent surface properties characterized by obtaining alloy cold-rolled material Manufacturing method of Umm alloy plate.