JP2007308805A - Aluminum alloy foil and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aluminum alloy foil which is superior in mechanical strength such as tensile strength and elongation, and has a good formability and less pinhole. <P>SOLUTION: The aluminum alloy foil is a long-shaped aluminum alloy foil which comprises Si: 0.04-0.2 wt.%, Fe: 1.0-2.0 wt.%, Cu: 0.01 wt.% or lower, Mg: 0.01 wt.% or lower, and balance Al with inevitable impurities; has an average grain size of 5-20 μm, an average subgrain size of 0.5-3.0 μm; and in which the dispersion density of an Al-Fe compound having a grain size of 0.1-2.0 μm is 3×10<SP>5</SP>-20×10<SP>5</SP>pieces/mm<SP>2</SP>, the dispersion density of an Al-Fe compound having a grain size exceeding 2.0 μm is 1×10<SP>4</SP>-10×10<SP>4</SP>pieces/mm<SP>2</SP>, and the surface roughness Ra in the longitudinal direction in a mat surface is 0.1-0.4 μm and the surface roughness in the width direction Ra is 0.05-0.2 μm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to an aluminum alloy foil having excellent formability, high strength and few pinholes, and a method for producing the same .

  Conventionally, 8079 alloy or 8021 alloy specified in JIS H4160 has been used as a material for aluminum alloy foil, and aluminum alloy foil is formed by homogenizing treatment process, hot rolling process and ingot of aluminum alloy. It is manufactured by performing an intermediate annealing step between the cold rolling step and, if necessary, the cold annealing process in the final annealing step and / or the cold rolling step.

  The aluminum alloy foil having a thickness of 5.5 to 7.0 μm has been put into practical use, and a thickness of 6.0 to 7.0 μm is often used. When the thickness of the aluminum alloy foil is reduced, the number of pinholes increases remarkably. When a large number of pinholes are generated, the barrier property against light, gas, liquid, etc., which is an inherent property of the aluminum alloy foil, is reduced. It is known that a problem that a foil breakage may occur in the cold rolling process during the manufacturing process.

  The hot rolling process and the cold rolling process of the aluminum alloy foil are usually performed by superposition rolling in which two rolled foils (sheets) are stacked and supplied between the rolls, and the outer surface in contact with the rolling roll is the bright surface. The opposing surfaces of the rolled foils are formed on the mat surface.

  The pinhole is known to be formed by connecting a deep valley portion in the uneven portion formed on the mat surface of the aluminum alloy foil and an oil pit formed on the bright surface. It is also known that the generation of holes tends to occur as the surface roughness of the mat surface of the aluminum alloy foil increases.

  Therefore, in Patent Document 1, dynamic recovery occurs by suppressing the work hardening during rolling by increasing the Fe content and adjusting the manufacturing conditions after the homogenization treatment step to refine the crystal grains. An aluminum alloy foil that suppresses the generation of pinholes in an easy manner is disclosed.

  However, in the aluminum alloy foil, not only the effect of suppressing the work hardening so much can be obtained, but depending on the production conditions, the crystal grains may become large, and on the contrary, the generation of pinholes is promoted. There was a point.

JP-A 63-26322

The present invention provides an aluminum alloy foil having excellent mechanical strength such as tensile strength and elongation and formability, and having few pinholes, and a method for producing the same.

The aluminum alloy foil of the present invention has Si: 0.04 to 0.2% by weight, Fe: 1.0 to 2.0% by weight, Cu: 0.01% by weight or less, Mg: 0.01% by weight or less, The remainder consists of Al and other inevitable impurities, the average crystal grain size is 5 to 20 μm, the average grain size of subgrains is 0.5 to 3.0 μm, and the grain size is 0.1 to 2.0 μm The dispersion density of the Al—Fe compound having a dispersion density of the Fe compound of 3 × 10 ^{5 to} 20 × 10 ⁵ particles / mm ² and a particle diameter exceeding 2.0 μm is 1 × 10 ⁴ to 10 × 10 ⁴ particles / mm. a elongated aluminum alloy foil is ^2, the surface roughness Ra in the length direction of the mat surface is the surface roughness Ra of a and and width 0.1 to 0.4 [mu] m from .05 to 0. It is characterized by being 2 μm .

  In other words, the aluminum alloy foil of the present invention has the above-described configuration, thereby suppressing the work hardening during rolling, facilitating dynamic recovery, excellent formability, high strength, and a small number of pinholes. It has become.

  When the content of Si in the aluminum alloy foil is large, a compound containing Si or simple substance Si precipitates and recrystallization is promoted too much, and the crystal grain size becomes coarse and the generation of pinholes increases. Since the corrosion reaction progresses by making a local battery with an Al component, the corrosion resistance decreases, and if it is small, it is necessary to use a high-purity aluminum ingot as the material of the aluminum alloy foil, so the cost increases. It is limited to 0.04 to 0.2% by weight.

  When the content of Fe in the aluminum alloy foil is large, a local battery is formed with an Al component, the corrosion reaction proceeds and the corrosion resistance is lowered, and when the content is small, the Al-Fe compound that promotes dynamic recovery. Is reduced, and the number of pin holes in the aluminum alloy foil is increased, so that it is limited to 1.0 to 2.0% by weight.

  In addition, when the content of Cu in the aluminum alloy foil is large, the amount of solid solution Cu increases, and the Al—Fe compound that can no longer dissolve is rapidly precipitated in the cold rolling process. As a result, the aluminum alloy Since the average crystal grain size of the foil increases and the number of pinholes in the aluminum alloy foil increases, it is limited to 0.01% by weight or less.

  Furthermore, if the content of Mg in the aluminum alloy foil is large, Mg is concentrated at the interface between the aluminum base and the aluminum oxide film to form an MgO layer, and this MgO layer becomes a weak boundary layer and becomes aluminum. Since the adhesiveness of the alloy foil is lowered, it is limited to 0.01% by weight or less.

  If the average crystal grain size of the aluminum alloy foil exceeds 20 μm, the surface roughness of the mat surface (matte surface) cannot be reduced, and the number of pin holes in the aluminum alloy foil increases or aluminum The mechanical strength of the alloy foil is reduced, and aluminum alloy foils having an average grain size of less than 5 μm are currently technically difficult and limited to 5-20 μm. The average crystal grain size of the aluminum alloy foil refers to that measured in accordance with JIS G0553 “Testing method for the ferrite crystal grain size of steel”.

  Further, if the average grain size of the subgrains of the aluminum alloy foil exceeds 3.0 μm, the surface roughness of the mat surface (matte surface) cannot be reduced, and the number of pin holes in the aluminum alloy foil is large. Or the mechanical strength of the aluminum alloy foil is reduced, and aluminum alloy foils having an average crystal grain size of less than 0.5 μm are currently technically difficult and limited to 0.5 to 3.0 μm. . In addition, the subgrain of aluminum alloy foil refers to a crystal grain having a small inclination existing in the crystal grain.

  Here, the average grain size of the subgrains of the aluminum alloy foil is measured in the following manner. In the case of an aluminum alloy foil having a thickness of 10 μm or more, a test solution obtained by mixing nitric acid and methyl alcohol at a volume ratio of 1: 3 is maintained at 0 ° C. or less, and aluminum is contained in the test solution. After the aluminum alloy foil surface is jet-polished while the alloy foil is immersed, and in the case of an aluminum alloy foil having a thickness of less than 10 μm, after degreasing in acetone without jet polishing, a transmission electron microscope is used. Using this, 20 surfaces of the aluminum alloy foil surface are observed under the condition of an acceleration voltage of 200 kV and 5000 times. Then, in the image obtained by the EBSD (Electron Back Scattering Diffraction pattern) method, subgrains having a crystal orientation difference of 20 ° or less were used as subgrains, and the above-mentioned transmission electron micrograph was also referred to, The average particle size can be measured.

  Further, the aluminum alloy foil usually has a thickness of 5.5 to 7.0 μm, and the aluminum alloy foil contains and disperses Al—Fe compound. When the diameter is larger than the thickness of the aluminum alloy foil, the Al—Fe compound protrudes from the surface of the aluminum alloy foil, and the protruding portion of the Al—Fe compound is harder than the aluminum base and easily causes pinholes. At the same time, since the Al—Fe compound is exposed on the surface of the aluminum alloy foil, the corrosion resistance is also lowered.

  Therefore, the Al—Fe compound in the aluminum alloy foil can reduce the number of pinholes generated in the aluminum alloy foil by decreasing the number of particles having a large particle size while increasing the number of particles having a small particle size. In addition, the said Al-Fe compound says the intermetallic compound formed with Al and Fe, and Si, Mn, etc. may contain a little in the Al-Fe compound.

That is, if the dispersion density of the Al—Fe compound having a particle size of 0.1 to 2.0 μm in the aluminum alloy foil is large, the amount of the Al—Fe compound is excessive, which may cause pinholes in the aluminum alloy foil. Or the corrosion resistance of the aluminum alloy foil is lowered, and if it is small, the average crystal grain size of the aluminum alloy foil does not become fine and causes pinholes in the aluminum alloy foil, so that 3 × 10 ^{5 to} 20 It is limited to × 10 ⁵ pieces / mm ² .

When the dispersion density of the Al—Fe compound having a particle size exceeding 2.0 μm in the aluminum alloy foil is large, the number of Al—Fe compounds exposed on the surface of the aluminum alloy foil increases as the foil becomes thin. If it is small, the number of Al—Fe compounds exposed on the surface of the aluminum alloy foil is small, so the number is limited to 1 × 10 ⁴ to 10 × 10 ⁴ pieces / mm ² .

  Here, the particle diameter and dispersion density of the Al—Fe compound are those measured in the following manner. In the case of an aluminum alloy foil having a thickness of 10 μm or more, a test solution obtained by mixing nitric acid and methyl alcohol at a volume ratio of 1: 3 is maintained at 0 ° C. or less, and aluminum is contained in the test solution. After the aluminum alloy foil surface is jet-polished while the alloy foil is immersed, and in the case of an aluminum alloy foil having a thickness of less than 10 μm, after degreasing in acetone without jet polishing, a transmission electron microscope is used. When using an Al-Fe compound having an acceleration voltage of 200 kV and measuring an Al-Fe compound having a particle size of 0.1 to 2.0 µm, the Al-Fe compound has a particle size exceeding 10000 times and a particle size exceeding 2.0 µm. When measuring the above, observe 20 fields at 2500 × each.

  Then, using an image analysis apparatus based on the above photograph, first, after binarizing the image and removing noise, the area occupied by one Al—Fe compound is measured, and a virtual circle corresponding to the area is measured. The diameter is defined as the particle size. Note that in the case where a plurality of Al—Fe compounds are combined to form an aggregate, the aggregate is regarded as one Al—Fe compound.

  In addition, there are locations where the Al—Fe compound has fallen off by jet polishing, but these are all present at locations where the Al—Fe compound has fallen off, and the particle diameter and number of the Al—Fe compound are measured. Based on the particle diameter and number of the Al—Fe compound, the dispersion density of the Al—Fe compound having a particle diameter of 0.1 to 2.0 μm and the Al—Fe compound having a particle diameter exceeding 2.0 μm is calculated. be able to. An example of the image analysis apparatus is a product name “V10LAB” manufactured by Toyobo Co., Ltd.

  The aluminum alloy foil contains inevitable impurities such as Ti, Zn, B, Ga, Ni, Mn, Cr, Sn, Pb, and V in addition to Si, Fe, Cu, Mg, and Al. And Ti produces | generates a compound with B and refines | miniaturizes the crystal grain of aluminum alloy foil, but when many, it may cause the pinhole of aluminum alloy foil, Therefore 0.02 in aluminum alloy foil, % By weight or less is preferred. For the same reason, the content of B in the aluminum alloy foil is preferably 0.01% by weight or less.

  And if there is much content of Zn in aluminum alloy foil, since the corrosion resistance of aluminum alloy foil may fall, 0.01 weight% or less is preferable. Furthermore, if the Ga content in the aluminum alloy foil is large, the recrystallized grains in the aluminum alloy foil may be coarsened to cause pin holes in the aluminum alloy foil. Is preferred.

  Furthermore, when the weight ratio (Fe / Si) between the Fe content and the Si content in the aluminum alloy foil is large, the amount of Fe contained in the aluminum alloy foil relatively increases, and pin holes are formed in the aluminum alloy foil. May occur, and the corrosion resistance of the aluminum alloy foil may decrease. If the amount is small, the content of Si in the aluminum alloy foil increases, and in addition to the Al-Fe compound, an Al-Fe-Si compound or Since single Si is likely to be precipitated and the aluminum alloy foil may be easily hardened, 10 to 50 is preferable.

  One surface of the aluminum alloy foil is formed on a mat surface (matte surface), while the other surface is formed on a bright surface (matt surface), and the mat surface has an uneven portion. Since the bright surface is a roll contact surface in the rolling process, almost no irregularities are formed.

  The aluminum alloy foil is manufactured through a final annealing step as necessary. In this final annealing step, the aluminum alloy foil is wound around a steel pipe, and the surface of the aluminum alloy foil is obtained. The oil adhering to is evaporated and removed in a direction perpendicular to the winding direction of the aluminum alloy foil around the steel pipe through the gap between the opposing surfaces of the aluminum alloy foil that are in contact with each other in the inner and outer directions.

  Also, the difference between the uneven portions formed on the mat surface of the aluminum alloy foil, that is, the larger the surface roughness, the larger the gap between the opposing surfaces of the aluminum alloy foil that abut against each other in the inner and outer directions. On the other hand, when the surface roughness of the mat surface of the aluminum alloy foil is increased, pinholes are easily generated in the aluminum alloy foil.

  Therefore, in the aluminum alloy foil of the present invention, the winding direction of the aluminum alloy foil around the steel pipe, that is, the surface roughness Ra in the length direction of the mat surface of the aluminum alloy foil formed in a long shape is increased, While promoting the transpiration and removal of the oil on the surface of the aluminum alloy foil in the final annealing step, the adhesiveness of the aluminum alloy foil surface is improved, while the direction orthogonal to the winding direction of the aluminum alloy foil on the steel pipe, The occurrence of pinholes is suppressed by reducing the surface roughness Ra in the width direction on the mat surface of the long aluminum alloy foil.

Specifically, if the surface roughness Ra in the length direction on the mat surface of the aluminum alloy foil of the present invention is large, pinholes are likely to be generated in the aluminum alloy foil, and if the surface roughness Ra is small, the surface roughness Ra of the aluminum alloy foil is small. Since the transpiration and removal of the oil becomes insufficient and the adhesiveness of the aluminum alloy foil may be lowered, it is limited to 0.1 to 0.4 μm.

On the other hand, if the surface roughness Ra in the width direction of the mat surface of the aluminum alloy foil of the present invention is large, pinholes are likely to occur in the aluminum alloy foil, and if it is small, the transpiration of oil on the aluminum alloy foil surface, Since removal may be insufficient and the adhesiveness of the aluminum alloy foil may be lowered, the thickness is limited to 0.05 to 0.2 μm.

The surface roughness Ra of the matte side surface of the aluminum alloy foil has been measured in accordance with JIS B0601 ^-2001, specifically, in the length direction of the matte surface of the aluminum alloy foil surface roughness The degree Ra is an average value of surface roughness Ra measured at five arbitrary points in the length direction on the surface of the mat surface of the aluminum alloy foil. Similarly, the surface in the width direction of the mat surface of the aluminum alloy foil. The roughness Ra is an average value obtained by measuring the surface roughness Ra at five arbitrary points in the width direction on the surface of the mat surface of the aluminum alloy foil.

  Further, if the amount of —COO (carboxyl group) on the mat surface of the aluminum alloy foil is large, excessive functional groups will be present, and surplus functional groups will form hydrogen bonds with —OH groups present on the aluminum surface. Then, the interface between the aluminum oxide film and the adhesive layer or film becomes brittle over time, the interface may be easily peeled off, and the adhesiveness may be reduced. 0.15 to 5.0 atomic% is preferable since the initial adhesive strength may be reduced.

  The amount of —COO (carboxyl group) on the mat surface of the aluminum alloy foil is determined by irradiating the surface of the mat surface of the aluminum alloy foil with Al-kα rays using an X-ray photoelectron spectrometer, [Al2p] [C1s] [O1s] The peak of the orbit is analyzed, and each peak area ratio (%) (this is defined as Mc) is measured.

  For each peak of [c1s], the binding energy at the peak position of the —C—C bond is adjusted to 285.0 eV, and then the peak area of —COO (binding energy: 289.2 eV) is set to the total [C1s]. The ratio (%) to the peak area (referred to as Sc) was determined.

  Next, by multiplying Mc and Sc, the peak area of -COO bond with respect to the total strength of Al, C, and O existing on the foil surface, that is, the amount of -COO (carboxyl group) on the mat surface of the aluminum alloy foil. Can be calculated.

  Next, the manufacturing method of the said aluminum alloy foil is demonstrated. First, Si: 0.04 to 0.2% by weight, Fe: 1.0 to 2.0% by weight, Cu: 0.01% by weight or less, Mg: 0.01% by weight or less, the rest being Al and other inevitable Ingot made of impurities, preferably Si: 0.04 to 0.2% by weight, Fe: 1.0 to 2.0% by weight, Cu: 0.01% by weight or less, Mg: 0.01% by weight or less , Ti: 0.02% by weight or less, Zn: 0.01% by weight or less, B: 0.01% by weight or less, Ga: 0.01% by weight or less, and the remainder comprising Al and other inevitable impurities An aluminum alloy foil having a thickness of less than 500 μm can be manufactured by sequentially performing a homogenization treatment process, a hot rolling process, and a cold rolling process, and finally a final annealing process as necessary. .

  In the method for producing an aluminum alloy foil, the cold rolling step is a cold rolling step for producing a normal aluminum alloy foil except for the rolling rate and the rolling foil (plate) temperature condition immediately after rolling as described below. Specifically, the cold rolling process of supplying and rolling a long rolled foil (plate) between a pair of rolls is repeated a plurality of times, and a plurality of times as described above. The cold rolling process immediately before the final cold rolling process in the cold rolling process (hereinafter referred to as “immediately cold rolling process”) has a rolling rate of 50 to 80% and the rolled foil temperature immediately after rolling. While performing so that it may become 110-200 degreeC, the final cold rolling process (henceforth "finish cold rolling process"), the rolling rate is 50% or less, and the rolling foil temperature immediately after rolling is 80 degrees C or less To do so.

Note that the above reduction ratio, the thickness of the rolled foil before cold rolling process to be t _0, the thickness of the rolled foil after cold rolling treatment and t _1, it refers to those calculated by the following equation.
[Rolling ratio] (%) = 100 × (t ₀ −t ₁ ) / t ₀

  If the rolling rate of the immediately preceding cold rolling treatment is small, dynamic recovery of the foil is difficult to occur during foil rolling, and the size of the Al-Fe compound contained in the aluminum alloy foil increases or the aluminum alloy When the final annealing step is performed on the foil, the average crystal grain size of the aluminum alloy foil may increase and cause pinholes, and a rolling rate exceeding 80% is practically difficult. % Is preferred.

  Moreover, if the rolling foil temperature immediately after rolling in the immediately preceding cold rolling process is high, it will recrystallize and the average crystal grain size of the aluminum alloy foil will increase, which may cause pinholes, If it is low, it is difficult for the foil to dynamically recover during foil rolling, and the size of the Al-Fe compound contained in the aluminum alloy foil is increased, or the aluminum alloy foil is subjected to a final annealing step. Since the average crystal grain size of the alloy foil may increase and cause pinholes, 110 to 200 ° C. is preferable.

  And if the rolling rate of a finish cold rolling process is large, not only dynamic recovery but the precipitation amount of an Al-Fe compound may become large, Therefore 50% or less is preferable. In addition, when the temperature of the rolled foil immediately after rolling in the finish cold rolling process is high, the average grain size of the aluminum alloy foil may increase when the final annealing step is performed on the aluminum alloy foil. preferable.

  Furthermore, the cold rolling process (hereinafter referred to as “pre-cold rolling process”) two times before the final cold rolling process has a rolling rate of 50 to 80% and the rolled foil temperature immediately after rolling is 110 to 200. It is preferable to carry out so that it may become ° C.

  That is, if the rolling rate of the pre-cold rolling process is small, dynamic recovery of the foil is difficult to occur during foil rolling, and the size of the Al—Fe compound contained in the aluminum alloy foil is increased. When the final annealing step is performed on the aluminum alloy foil, the average crystal grain size of the aluminum alloy foil may increase and cause pinholes, and a rolling rate exceeding 80% is practically difficult. ~ 80% is preferred.

  Moreover, if the temperature of the rolled foil immediately after rolling in the pre-cold rolling process is high, recrystallization causes an average crystal grain size of the aluminum alloy foil to increase, which may cause pinholes. If it is low, it is difficult for the foil to dynamically recover during foil rolling, and the size of the Al-Fe compound contained in the aluminum alloy foil is increased, or the aluminum alloy foil is subjected to a final annealing step. Since the average crystal grain size of the alloy foil may increase and cause pinholes, 110 to 200 ° C. is preferable.

  Moreover, the rolled sheet after performing the hot rolling process usually has a thickness of about 2 to 8 mm, and this rolled sheet is repeatedly subjected to the cold rolling process in the cold rolling process a plurality of times, Usually, the aluminum alloy foil is rolled to a thickness of 5.5 to 7.0 μm.

  At this time, an intermediate annealing process may be performed on the rolled sheet during the cold rolling process in which the thickness of the rolled sheet to be subjected to the cold rolling process is 500 μm or more and is continuous in time.

  The intermediate annealing step is performed in the same manner as the intermediate annealing step in the ordinary aluminum alloy foil manufacturing method except for the intermediate annealing conditions shown below, specifically, under the intermediate annealing conditions shown below. The long rolled sheet is wound around the steel pipe and left in the air under the following intermediate annealing conditions, or the long rolled sheet is unwound from the state wound around the steel pipe, and this unwinding is performed. This is done by continuously passing the rolled sheet in a non-oxidizing atmosphere maintained under the following intermediate annealing conditions.

  As conditions for the intermediate annealing step, point a (350 ° C., 1 hour), point b (350 ° C., 10 hours) in the graph in which the horizontal axis indicates temperature and the vertical axis indicates time as shown in FIG. ), C point (550 ° C., 1 minute) and d point (550 ° C., 1 hour) are preferably performed under the temperature and time conditions included in the hatched portion surrounded by a rectangle formed by connecting the four points. .

  If the temperature is lower than the point a and the time is shorter than the point a or shorter than the point c, in the rolled foil, recrystallization or precipitation of the Al—Fe compound is insufficient and the foil is being rolled. In some cases, the recrystallization or the Al—Fe compound may be insufficient if the temperature recovery is insufficient and the temperature is lower and longer than the point b or higher than the point d. As a result of excessive precipitation, the average crystal grain size of the aluminum alloy foil becomes large, or the number of Al—Fe compounds having a grain size exceeding 2.0 μm increases so much that many pinholes are generated in the aluminum alloy foil. Because there is a fear.

  Finally, the homogenization process, the hot rolling process, and the final annealing process in the method for manufacturing the aluminum alloy foil are performed in the same manner as the method for manufacturing a normal aluminum alloy foil.

  Specifically, the homogenization treatment step of the aluminum alloy foil is a method in which the aluminum alloy ingot is homogeneously heated in order to minimize segregation of elemental components contained in the aluminum alloy ingot, and the hot rolling step The ingot in a heated state after the homogenization treatment step is made into a pair of upper and lower pairs of rolls, and a series of rolls in which a plurality of sets of rolls are arranged side by side are sequentially and continuously. The rolled foil (plate) is fed and rolled between rolls while being kept in a heated state.

  The aluminum alloy foil produced as described above is suitably used for various applications, and in particular, an aluminum laminate formed by laminating and integrating paper on one surface of the aluminum alloy foil via an adhesive It is suitably used as a packaging sheet for packaging articles such as confectionery and tobacco, and is particularly preferably used for packaging tobacco.

  The adhesive is not particularly limited as long as the aluminum alloy foil and paper can be bonded and integrated. For example, polyvinyl acetate; ethylene-vinyl acetate copolymer; (meth) acrylic polymer; ethylene and Examples include ionomers obtained by causing a metal ion such as Na or Zn to crosslink with a copolymer with an acrylic monomer such as acrylic acid or methacrylic acid; ethyl polymaleate; polyacrylic acid amide.

  The (meth) acrylic polymer is not particularly limited. For example, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, Examples include (meth) acrylic acid esters such as (meth) acrylic acid dodecyl, and homopolymers or copolymers of acrylic monomers such as (meth) acrylic acid.

  The (meth) acrylic polymer may be a copolymer of the acrylic monomer and a vinyl monomer copolymerizable therewith. Examples thereof include (meth) acrylic acid amide, vinyl acetate, vinyl pivalate, vinyl propionate, styrene, acrylonitrile and the like. Examples of the copolymer of the acrylic monomer and the vinyl monomer copolymerizable therewith include, for example, acrylic ester-methacrylic ester-styrene terpolymer, acrylonitrile-acrylic acid-styrene. Examples include terpolymers.

  And when using the said aluminum laminated body for tobacco packaging, among the said adhesive agents, a polyvinyl acetate, ethylene-vinyl acetate copolymer, poly (meth) acrylic acid methyl, poly (meth) ethyl acrylate Preferred are poly (meth) acrylic acid esters, ionomers obtained by crosslinking a metal ion such as Na and Zn with a copolymer of ethylene and acrylic monomers such as acrylic acid and methacrylic acid, and ethyl polymaleate. , Polyvinyl acetate, ethylene-vinyl acetate copolymer, poly (meth) acrylic acid ester, ethylene- (meth) acrylic acid copolymer, and ionomer or ethylene- (meth) acrylic acid obtained by crosslinking Na by acting on Na More preferable is an ionomer formed by allowing Zn to act on the copolymer and cross-linking the ethylene- (meth) acrylate. Ionomers, ethylene made by crosslinking by the action of Na in acrylic acid copolymer - (meth) ionomers made by crosslinking by the action of Zn acrylic acid copolymer is particularly preferred.

The paper is not particularly limited, and examples thereof include 15-60 g / m ² thin paper, high-quality paper, pure white roll paper, and the like.

  And it does not specifically limit as a method of manufacturing the said aluminum laminated body, For example, after apply | coating an adhesive agent to the one surface of the said aluminum alloy foil, paper is laminated | stacked on the adhesive agent coating surface of this aluminum alloy foil, and it adhere | attaches. A method for producing an aluminum laminate in which an aluminum foil and paper are integrated with an agent is mentioned. In applying the adhesive to the aluminum alloy foil, it is preferable to use an emulsified adhesive.

The aluminum alloy foil according to claim 1 is Si: 0.04 to 0.2 wt%, Fe: 1.0 to 2.0 wt%, Cu: 0.01 wt% or less, Mg: 0.01 wt% %, The remainder is made of Al and other inevitable impurities, the average crystal grain size is 5 to 20 μm, the average grain size of subgrains is 0.5 to 3.0 μm, and the grain size is 0.1 to 2. The dispersion density of the Al—Fe compound having a particle size of 2.0 × m and the dispersion density of 1 × 10 ⁴ to 10 × 10 ⁴ is 3 × 10 ^{5 to} 20 × 10 ⁵ particles / mm ^2. Piece / mm ^2, which is a long aluminum alloy foil having a surface roughness Ra in the length direction of the mat surface of 0.1 to 0.4 μm and a surface roughness Ra in the width direction of 0.05. It is characterized by being -0.2 μm, so it has excellent tensile strength and extensibility, and good composition. It has shape and has few pinholes.

  Furthermore, the aluminum alloy foil has excellent tensile strength and elongation, and has a good Erichsen value. Therefore, the foil does not break during production and is excellent in productivity.

  As described above, the aluminum alloy foil has excellent tensile strength and elongation and has a small number of pinholes. Therefore, the aluminum alloy foil is preferably used for household goods, film capacitor applications, confectionery packaging applications, and the like. The aluminum alloy foil can be formed, bent, and cut into a desired shape without causing cracks or breaks in the aluminum alloy foil.

Further, the aluminum alloy foil is formed in a long shape, the surface roughness Ra in the length direction on the mat surface is 0.1 to 0.4 μm, and the surface roughness Ra in the width direction is 0.05 to 0. It is characterized by being 2 μm, and during the final annealing, the oil adhering to the surface of the aluminum alloy foil is smoothly and satisfactorily evaporated and removed to express excellent adhesiveness, and the mat surface of the aluminum alloy foil In addition, a laminated sheet such as paper or synthetic resin can be firmly and reliably laminated and integrated through an adhesive.

And the aluminum alloy foil of Claim 2 is the aluminum alloy foil of Claim 1 , Si: 0.04-0.2 weight%, Fe: 1.0-2.0 weight%, Cu: 0.01 wt% or less, Mg: 0.01 wt% or less, Ti: 0.02 wt% or less, Zn: 0.01 wt% or less, B: 0.01 wt% or less, Ga: 0.01 wt% Since the following is characterized in that the remainder is made of Al and other inevitable impurities, the number of pin holes in the aluminum alloy foil can be reduced, and more excellent formability and productivity can be exhibited.

Furthermore, the manufacturing method of the aluminum alloy foil according to claim 3 is as follows: Si: 0.04 to 0.2 wt%, Fe: 1.0 to 2.0 wt%, Cu: 0.01 wt% or less, Mg : An aluminum alloy foil having a thickness of less than 500 μm is manufactured by successively performing a homogenization process, a hot rolling process, and a cold rolling process on an ingot made of 0.01% by weight or less and the balance of Al and other inevitable impurities. A method for producing an aluminum alloy foil, wherein the cold rolling step is performed by repeating the cold rolling treatment a plurality of times, and the cold rolling treatment immediately before the final cold rolling treatment is performed at a rolling rate of 50 to 80%. And the final cold rolling process is performed so that the rolling rate is 50% or less and the rolling foil temperature immediately after rolling is 80 ° C. or less. Because it is characterized by Number pinholes less aluminum alloy foil can be efficiently and reliably manufactured with a and a better and good moldability elongation properties.

Further, the method for producing an aluminum alloy foil according to claim 4 is the method for producing an aluminum alloy foil according to claim 3 , wherein the rolling rate is the same as that in the cold rolling treatment immediately before the final cold rolling treatment. Since the rolling foil temperature is 50 to 80% and the rolling foil temperature immediately after rolling is 110 to 200 ° C., an aluminum alloy foil having a smaller number of pinholes can be easily and reliably produced.

And the manufacturing method of the aluminum alloy foil of Claim 5 WHEREIN: The manufacturing method of the aluminum alloy foil of Claim 3 or Claim 4 cold-rolls the rolled sheet 500 micrometers or more in thickness, and back and forth An intermediate annealing step was performed on the rolled sheet between successive cold rolling processes, and this intermediate annealing step was performed at 350 ° C. for 1 hour in a graph with temperature on the horizontal axis and time on the vertical axis. 10 hours), (550 ° C., 1 minute), and (550 ° C., 1 hour), which is performed under the temperature and time conditions included in the portion surrounded by a square formed by connecting the four points. Therefore, an aluminum alloy foil having a small number of pinholes and excellent formability can be easily and reliably manufactured.

(Examples 1-7, 11-13)
Using ingots having a chemical composition of A to G listed in Table 1 and having a thickness of 500 mm as shown in Table 3 for each example, the ingot was subjected to a homogenization treatment process at 540 ° C. for 4 hours. Then, a hot rolling process was immediately performed to obtain a 2.5 mm thick plate.

  Subsequently, cold rolling treatment was repeatedly performed on the 2.5 mm-thick plate to obtain an aluminum alloy foil having a thickness of 5.5 μm. In addition, the rolling conditions of the pre-cold rolling process, the last cold rolling process, and the finish cold rolling process were performed according to each rolling condition shown in Table 3 for every Example.

(Example 8)
Using a 500 mm-thick ingot having the chemical composition of A shown in Table 1, the ingot was subjected to a homogenization treatment process at 540 ° C. for 4 hours, and then immediately subjected to a hot rolling step to obtain a thickness. A 2.5 mm plate was obtained.

  Subsequently, the cold rolling process was repeated a plurality of times on the 2.5 mm-thick plate to obtain a 540 μm-thick rolled plate, and this rolled plate was subjected to an intermediate annealing step at 350 ° C. for 4 hours. .

  Further, the rolled foil subjected to the intermediate annealing step was repeatedly subjected to cold rolling treatment a plurality of times to obtain an aluminum alloy foil having a thickness of 5.5 μm. The rolling conditions of the pre-cold rolling process, the immediately preceding cold rolling process, and the finish cold rolling process were performed according to the rolling condition a in Table 2.

Example 9
An aluminum alloy foil was obtained in the same manner as in Example 8 except that the intermediate annealing step was performed at 550 ° C. for 1 minute.

(Example 10)
An aluminum alloy foil was obtained in the same manner as in Example 8, except that the intermediate annealing step was performed at 450 ° C. for 1 hour, and the aluminum alloy foil was subjected to a final annealing step in the atmosphere at 260 ° C. for 50 hours. It was.

(Examples 14 to 16)
Using a 500 mm-thick ingot having the chemical composition of A shown in Table 1, the ingot was subjected to a homogenization treatment process at 540 ° C. for 4 hours, and then immediately subjected to a hot rolling step to obtain a thickness. A 2.5 mm plate was obtained.

  Subsequently, cold rolling treatment was repeatedly performed on the 2.5 mm thick plate to obtain an aluminum alloy foil having a predetermined thickness (rolled foil thickness after finish cold rolling treatment) shown in Table 2. . The rolling conditions of the pre-cold rolling process, the immediately preceding cold rolling process, and the finish cold rolling process were performed according to the rolling conditions shown in Table 3 for each example. Further, the aluminum alloy foil was subjected to a final annealing step in the atmosphere at 260 ° C. for 50 hours.

(Comparative Examples 1-10)
A 500 mm thick ingot having the chemical compositions A and H to J listed in Table 1 was used for each comparative example as shown in Table 3, and the ingot was homogenized at 540 ° C. for 4 hours. Then, a hot rolling step was immediately performed to obtain a 2.5 mm thick plate.

  Subsequently, cold rolling treatment was repeatedly performed on the 2.5 mm thick plate to obtain an aluminum alloy foil having a predetermined thickness (rolled foil thickness after finish cold rolling treatment) shown in Table 2. . In addition, the rolling conditions of the pre-cold rolling process, the last cold rolling process, and the finish cold rolling process were performed according to the rolling conditions shown in Table 3 for each comparative example. Further, the aluminum alloy foil was subjected to a final annealing step in the atmosphere at 260 ° C. for 50 hours.

  The average grain size of the aluminum alloy foil obtained as described above, the average grain size of the subgrain, the grain size and dispersion density of the Al-Fe compound, the surface roughness Ra of the mat surface, and -COO of the surface of the aluminum alloy foil The amount, tensile strength, elongation, Erichsen value, number of pinholes, and adhesiveness were measured as shown below, and the results are shown in Table 3.

(Surface roughness Ra of mat surface)
The surface roughness Ra in the length direction and the width direction on the mat surface of the aluminum alloy foil was measured with a contact mode stylus using a tabletop small probe microscope (trade name “Nanopics 1000” manufactured by Seiko Instruments Inc.).

(Tensile strength and elongation)
A 12 cm long x 1.5 cm wide test piece was cut out from the aluminum alloy foil, and the tensile strength and elongation of the test piece were measured using a tensile strength tester (trade name “Instron Autograph DSS-500” manufactured by Shimadzu Corporation). using, in accordance with the JIS Z2241 ^-1998 Distance between chucks 50 mm, tensile speed 10 mm / min. The measurement was performed under the following conditions.

(Erichsen value)
The Erichsen value of the aluminum alloy foil was measured five times in accordance with JIS Z2247 using a tester in accordance with JIS B7729. And the average value of the said 5 times of measured values was computed using the rounding method of the numerical value based on JISZ8401.

(Number of pinholes)
Ten flat square test pieces each having a side of 500 mm were cut out from the aluminum alloy foil, the number of pinholes was visually counted for each test piece, and the number of pinholes was divided by the plane area of the test piece to obtain a 1 mm ² area. The number of per pinholes was calculated, and the average value was defined as the number of pinholes.

(Adhesiveness)
The adhesion of the matte surface of the aluminum alloy foil was measured in accordance with JIS K6854 ^-1994.

  Furthermore, the aluminum laminated body for tobacco packaging was produced in the following ways using the said aluminum alloy foil.

(Preparation of aluminum laminate for tobacco packaging)
One of the adhesives shown in Table 4 was selected and applied as shown in Table 5 on one surface of each aluminum alloy foil produced in Examples 1-16 and Comparative Examples 1-10, and this aluminum alloy foil After laminating 20 g / m ² of thin paper on one side, the adhesive was dried, and the thin paper was laminated and integrated on one side of the aluminum alloy foil to produce an aluminum laminate for cigarette packaging.

  And the moisture permeability, static friction coefficient, and odor property of the aluminum laminated body for tobacco packaging produced as described above were measured in the following manner, and the results are shown in Table 5.

(Moisture permeability)
The moisture permeability of the cigarette packaging aluminum laminate was measured according to JIS Z0208 ^-1976 "moisture permeability test method of dry packing material (cup method)".

(Static friction coefficient)
In conformity with JIS P8147 ^-1994 defined in the "coefficient of friction testing method for paper and paperboard", it was measured static friction coefficient between the aluminum alloy foil and the stainless steel plate (SUS).

(Odor)
10 sheets of aluminum laminate for cigarette wrapping of 5 cm in length × 20 cm in width is sealed in a 10 liter plastic bag and allowed to stand for 24 hours, and then the five testers are allowed to smell the gas in the plastic bag, ◎ When all 5 people did not feel odor, ◎ When only one person feels odor a little, ○ When there are two or more people who feel odor △ When all five people feel odor × As evaluated.

It is the graph which illustrated the temperature and time condition range in an intermediate annealing process.

Explanation of symbols

a Intermediate annealing condition at a temperature of 350 ° C. and a time of 1 hour b Intermediate annealing condition at a temperature of 350 ° C. and a time of 10 hours c Intermediate annealing conditions at a temperature of 550 ° C. and a time of 1 minute d d Temperature at 550 ° C. and time 1 hour intermediate annealing condition

Claims (5)

Si: 0.04 to 0.2% by weight, Fe: 1.0 to 2.0% by weight, Cu: 0.01% by weight or less, Mg: 0.01% by weight or less, the remainder from Al and other inevitable impurities The average grain size is 5 to 20 μm, the subgrain average particle size is 0.5 to 3.0 μm, and the dispersion density of the Al—Fe compound having a particle size of 0.1 to 2.0 μm is 3 × 10 ⁵ ~20 × 10 ⁵ cells / elongated aluminum dispersion density of mm ² at and Al-Fe compound grain size exceeds 2.0μm is at 1 × 10 ⁴ ~10 × 10 ⁴ cells / mm ² An alloy foil , characterized in that the surface roughness Ra in the length direction on the mat surface is 0.1 to 0.4 μm and the surface roughness Ra in the width direction is 0.05 to 0.2 μm. Aluminum alloy foil. Si: 0.04 to 0.2% by weight, Fe: 1.0 to 2.0% by weight, Cu: 0.01% by weight or less, Mg: 0.01% by weight or less, Ti: 0.02% by weight or less Zn: 0.01% by weight or less, B: 0.01% by weight or less, Ga: 0.01% by weight or less, and the remainder consisting of Al and other inevitable impurities . Aluminum alloy foil. Si: 0.04 to 0.2% by weight, Fe: 1.0 to 2.0% by weight, Cu: 0.01% by weight or less, Mg: 0.01% by weight or less, the remainder from Al and other inevitable impurities A method for producing an aluminum alloy foil in which a homogenization treatment process, a hot rolling process, and a cold rolling process are sequentially performed on an ingot to produce an aluminum alloy foil having a thickness of less than 500 μm, wherein the cold rolling process includes: The cold rolling process is repeated a plurality of times, and the cold rolling process immediately before the final cold rolling process is performed so that the rolling rate is 50 to 80% and the rolled foil temperature immediately after rolling is 110 to 200 ° C. And a final cold rolling treatment is performed so that the rolling rate is 50% or less and the temperature of the rolled foil immediately after rolling is 80 ° C. or less . The cold rolling process immediately before the final cold rolling process is performed so that the rolling rate is 50 to 80% and the rolled foil temperature immediately after rolling is 110 to 200 ° C. The manufacturing method of the aluminum alloy foil as described in 2 . Cold rolling a rolled plate having a thickness of 500 μm or more and subjecting the rolled plate to an intermediate annealing step between successive cold rolling processes, the intermediate annealing step is performed with temperature on the horizontal axis and time on the vertical axis. Surrounded by a square formed by connecting four points (350 ° C., 1 hour), (350 ° C., 10 hours), (550 ° C., 1 minute) and (550 ° C., 1 hour) in the graph. The method for producing an aluminum alloy foil according to claim 3 or 4 , wherein the method is performed under conditions of temperature and time contained in the portion .

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