JP6058363B2 - Aluminum alloy foil, molded packaging material, battery, pharmaceutical packaging container, and method for producing aluminum alloy foil - Google Patents

Description

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

  For example, PTP (press-through package) packaging and strip packaging are known as packaging forms for pharmaceutical products. PTP packaging often takes the form of packaging by a combination of a container and a lid. Usually, as a container, what shape | molded plastic films, for example, resin films, such as a polypropylene, is used. Also, when packaging contents (tablets, capsules, etc.) that require water vapor barrier properties during storage, a composite made by bonding a highly barrier aluminum foil and a resin film on one or both sides is used as a container. Often used. In recent years, since there are various forms and sizes of pharmaceuticals, it has become necessary to form molded packages for packaging them in accordance with those forms and to be molded deeper than before.

  In addition, a composite body in which a resin film is bonded to both surfaces of an aluminum alloy foil is used in order to impart a water vapor barrier property to a molded package for packaging a battery such as a secondary battery, that is, an exterior material. In recent years, secondary batteries such as sheet-like thin lithium-ion secondary batteries have come in handy as a driving source for electronic devices such as mobile communication devices, notebook computers, headphone stereos, and camcorders. ing. Secondary batteries are required to have a charge capacity or high output that can withstand long-term use. For this reason, the structure of the element composed of the battery electrode and the separator has become complicated and multilayered, and molding under severe conditions such as deeper deep drawing has been required.

  In particular, the outer packaging material of the sheet-like thin lithium-ion secondary battery is formed with a rectangular tube drawing to form deeper recesses and further reduce the radius R of the shoulders and corners at the four corners of the recesses. Yes. As a result, the amount of battery material that can be stored in the recess is increased, and the battery capacity can be further increased. Currently, higher formability is required for the exterior material of the lithium ion secondary battery, and high formability is also required for the aluminum alloy foil constituting the exterior material.

  For example, an aluminum foil having a thickness of 20 to 60 μm and an elongation of 0%, 45 degrees and 90 degrees in the rolling direction is 11% or more is proposed as a packaging material body (Patent Document 1). In addition, the aluminum alloy foil excellent in corrosion resistance containing 0.8 to 2.0% Fe, 0.02 to 0.2% Cu, and 0.03 to 0.1% Si as the packaging material body. Has been proposed. (Patent Document 2).

JP 2005-163077 A JP 2006-31768 A

  However, with the prior art described in the above document, it has been difficult to satisfactorily satisfy applications that require high formability, such as exterior materials used in recent lithium ion secondary batteries and the like.

  In the aluminum alloy foil of Patent Document 1, when severe square tube drawing is performed so as to form a deep recess, cracks and pinholes may occur around the shoulder of the recess. In other words, there is no problem when forming a relatively shallow recess in the aluminum alloy foil, but if a deep recess is formed in the center of the molded packaging material to increase the capacity of the contents, Cracks and the like are likely to occur particularly at the corners of the package. As a result, moisture, air, and the like are likely to permeate the molded package, which has the disadvantage of adversely affecting the quality of the contents. In particular, when used as a secondary battery exterior material, hydrofluoric acid is generated by the reaction between the battery material and the electrolytic solution due to moisture and air, and the battery material is easily corroded. Further, in the aluminum alloy foil of Patent Document 1, in order to improve the formability, the elongation values in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction are improved. The yield strength is large. Accordingly, when the material flows from the flange portion into the hole portion of the molding die during the rectangular tube drawing, the inflow resistance of the material increases, and thus the molding height cannot be improved.

  In addition, in the aluminum alloy foil of Patent Document 2, the number of alloy components and intermetallic compounds is controlled in order to improve corrosion resistance and strength. However, it is not sufficient to improve the forming height only by controlling these. .

  The present invention has been made in view of the above circumstances, and an aluminum alloy foil having good formability, a molded packaging material for packaging pharmaceuticals and battery materials as a PTP or battery exterior material, a battery, and a pharmaceutical packaging container And it aims at providing the manufacturing method of aluminum alloy foil.

  The inventors of the present invention have studied aluminum alloy foils used for molded packaging materials. In an alloy system containing Fe, Si, and Cu, the metal components are mixed in an optimum amount, and the average crystal grain size is determined. By controlling the ingot homogenization temperature and intermediate annealing temperature in the manufacturing process within a predetermined range, and more preferably, the strength balance in the 0 degree, 45 degree and 90 degree directions with respect to the rolling direction of the aluminum alloy foil. Has been found to greatly improve the moldability and have led to the present invention.

  That is, the invention according to claim 1 contains Fe: 0.8 to 2.0 mass%, Si: 0.05 to 0.2 mass%, Cu: 0.2 to 0.5 mass%, with the balance being Al and An aluminum alloy foil comprising inevitable impurities and having an average crystal grain size of 7 to 20 μm or less.

  The invention according to claim 2 has a tensile strength of 0, 45, and 90 degrees in the rolling direction of 90 MPa or more, and a tensile strength TS of 0, 45, and 90 degrees in the rolling direction and 0 2. The aluminum alloy foil according to claim 1, wherein the value of TS × (TS / YS) in the 45 ° direction is 200 MPa or more at a 2% yield strength YS.

  In the above-described aspect, in the drawing, particularly in the rectangular tube drawing, the side wall strength is high, and when the material flows into the hole of the molding die from the flange portion, the inflow resistance of the material decreases. Can be improved.

  The invention according to claim 3 is a molded package material including the aluminum alloy foil according to claim 1 or claim 2.

  In the above aspect, since the aluminum alloy foil having the above-mentioned favorable formability is used, it is possible to form a deep concave portion with the molded package material and increase the molding height. As a result, it is possible to increase the amount that can be stored in the recess of the molded package.

  The invention according to claim 4 further comprises a synthetic resin film laminated on one side of the aluminum alloy foil, and a heat sealing layer laminated on the other side of the aluminum alloy foil. Item 4. The molded package material according to Item 3.

  The invention according to claim 5 is a battery comprising the molded package material according to claim 4.

  In the above aspect, since the molded packaging material that can increase the molding height in the drawing, particularly the rectangular tube drawing, the amount of the battery material that can be stored in the recess of the battery exterior material is increased. The battery capacity can be further increased.

  The invention according to claim 6 is a pharmaceutical packaging container comprising the molded packaging material according to claim 4.

  In the above aspect, since a molded packaging material capable of increasing the molding height is used in drawing, particularly rectangular tube drawing, it is possible to increase the filling amount of the medicine that can be stored in the recess of the medicine packaging container. it can.

  The invention according to claim 7 is Fe: 0.8 to 2.0 mass%, Si: 0.05 to 0.2 mass%, Cu: 0.2 to 0.5 mass%, the balance being Al and inevitable impurities. 300 steps of heat-treating the aluminum alloy ingot at 550 ° C. or more and 620 ° C. or less for 1 hour or more, a step of performing hot rolling and cold rolling after the heat treatment, and before or during the cold rolling, 300 A step of performing an intermediate annealing held at ˜450 ° C., a step of performing cold rolling at a cold rolling ratio of 93 to 99%, and a step of performing annealing to obtain the aluminum alloy foil, This is a method for producing an aluminum alloy foil.

  The present invention is an aluminum alloy foil suitable for a molded package material that requires high formability such as a lithium ion secondary battery because the aluminum alloy component and the average crystal grain size are optimally controlled, A molded packaging material, a battery including the molded packaging material, a pharmaceutical packaging container including the molded packaging material, and an aluminum alloy foil manufacturing method can be provided.

It is typical sectional drawing which showed the general example of the shaping | molding packaging material. It is typical sectional drawing which showed an example of the internal structure of a sheet-like thin lithium ion secondary battery.

Hereinafter, a mode for carrying out the present invention (hereinafter referred to as the present embodiment) will be specifically described.
(1) Composition of aluminum alloy foil The content of Fe in the aluminum alloy foil of the present embodiment is 0.8 to 2.0 mass%. When the Fe content is less than 0.8 mass%, both the tensile strength TS and the proof stress YS decrease, so the value of TS × (TS / YS) in the 45 ° direction with respect to the rolling direction becomes small, and the formability is low. descend. On the other hand, if the Fe content exceeds 2.0 mass%, a huge intermetallic compound is likely to be formed at the time of casting, and it becomes easy to become a starting point of cracking at the time of rectangular tube drawing, so that the formability is lowered. Among these numerical ranges, 1.1 mass% or more and 1.7 mass% or less are more preferable from the viewpoint of improving the strength.

  The Si content in the aluminum alloy foil of this embodiment is 0.05 to 0.2 mass%. When the Si content is less than 0.05 mass%, the tensile strength TS and the proof stress YS decrease, and therefore the value of 45 degrees with respect to the rolling direction and TS × (TS / YS) in the 90-degree direction decreases. Formability is reduced. In addition, a high-purity aluminum ingot is used, which is not economically preferable. On the other hand, if the Si content exceeds 0.2 mass%, the crystallized material size in the aluminum alloy foil increases, and the number of crystallized materials decreases. As a result, since the average crystal grain size after the final annealing is increased, non-uniform molding is likely to occur during molding, and moldability is deteriorated. Among these numerical ranges, 0.06 mass% or more and 0.1 mass% or less are particularly preferable from the viewpoint of improving the strength and optimizing the crystal grain size.

  The content of Cu in the aluminum alloy foil of this embodiment is 0.2 to 0.5 mass%. Strength is improved by containing Cu in aluminum alloy foil. Even if the Cu content is increased within the above range, the number of intermetallic compounds that can be nucleation sites during recrystallization hardly changes because most of the Cu is dissolved in the aluminum matrix. Therefore, when the content is in the above range, it is possible to obtain high strength by the influence of Cu dissolved in the aluminum matrix while maintaining the crystal grain size fine. When the Cu content is less than 0.2 mass%, the strength decreases, and therefore the value of TS × (TS / YS) in the 45 ° direction with respect to the rolling direction decreases, and the formability decreases. If the Cu content exceeds 0.5 mass%, work hardening during cold rolling becomes large, and the rollability is lowered. Among these numerical ranges, 0.2 mass% or more and 0.4 mass% or less are particularly preferable from the viewpoints of strength improvement and rollability.

  As described above, the contents of Fe, Si, and Cu in the aluminum alloy foil of the present embodiment are adjusted to optimal numerical ranges, respectively, and combined with the optimization of the average crystal grain size described later, formability is improved. To do. Moreover, in the aluminum alloy foil of this embodiment, a synergistic effect is exhibited by combining these metals, and high moldability is obtained.

  The aluminum alloy foil of the present embodiment may contain inevitable impurities such as Ti, Mn, Mg, Zn. The inevitable impurities contained in the aluminum alloy foil of the present embodiment are each preferably 0.05 mass% or less, and the total is preferably 0.15 mass% or less. In particular, if inevitable impurities are individually less than 0.05 mass% and more than 0.15 mass% in total, work hardening during cold rolling is large, and breakage may easily occur.

(2) Physical properties of aluminum alloy foil The average crystal grain size after the final annealing in the aluminum alloy foil of this embodiment is 7 μm or more and 20 μm or less. Preferably, they are 10 micrometers or more and 18 micrometers or less. The average crystal grain size of the present invention is a value measured using a cutting method. The cutting method is a method of calculating the average crystal grain size by counting how many crystal grains are present in a certain line segment and dividing the line segment by the number. The average crystal grain size of the aluminum alloy foil after the final annealing is greatly affected by the metal content and manufacturing conditions. In particular, it is greatly influenced by the contents of Fe and Si. Therefore, in order to obtain the average crystal grain size of the present embodiment, it is necessary to appropriately adjust the metal content and manufacturing conditions. If the average grain size is less than 7 μm, the average grain size is too fine, so that the 0.2% proof stress YS increases with respect to the tensile strength TS. Therefore, the value of TS × (TS / YS) in the 45 degree direction with respect to the rolling direction becomes small, and the formability deteriorates. On the other hand, when the average crystal grain size exceeds 20 μm, the number of crystal grains occupying in the plate thickness cross-sectional direction decreases. Thereby, since deformation concentrates only on specific crystal grains, formability is lowered.

  In the aluminum alloy foil of the present embodiment, the values of the tensile strength TS in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction are all preferably 90 MPa or more. In order to obtain a higher forming height in the rectangular tube drawing, it is more than the punch forming load that combines the friction force generated from the molding packaging material and the forming die and the inflow resistance of the material generated in the corner flange. The side wall strength of the molded package material is required to be large. In other words, improving the tensile strength of the molded packaging material improves the molding height in the rectangular tube drawing. Therefore, the higher the tensile strength of the aluminum alloy foil constituting the molded packaging material, the better. If the value of the tensile strength TS in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction is less than 90 MPa, it is easy to break at the side wall portion at the time of rectangular tube drawing, and therefore a higher forming height may not be obtained. is there.

  Here, the significance of the formula TS × (TS / YS) will be described. The value of (TS / YS) is the ratio of tensile strength to 0.2% proof stress. The larger this value is, the more regions where uniform deformation can be obtained, indicating that the material tends to flow from the flange portion to the hole portion of the molding die during square tube drawing. Further, the higher the tensile strength TS is, the better the fracture resistance is improved. That is, the aluminum alloy foil used in this embodiment is preferably a material having a high tensile strength TS and a low 0.2% proof stress YS. TS × (TS / YS), which is an expression obtained by multiplying the value of (TS / YS) by the tensile strength TS corresponding to the fracture resistance, has a very high correlation with the molding height in this embodiment, It can be used as one of indexes indicating moldability in rectangular tube drawing.

  The aluminum alloy foil of the present embodiment has a TS × (TS / YS) value of 200 MPa or more in the tensile strength TS and 0.2% proof stress YS in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction. Is recommended. If the value of TS × (TS / YS) in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction is less than 200 MPa, it is difficult to improve the formability. In the rectangular tube drawing of the molded packaging material having a thin plate thickness as in the present embodiment, the corner flange portions at the four corners are deformed by contraction as the molding height increases. Therefore, in the corner flange portion, the inflow resistance of the material is increased, and the material is less likely to flow. In the corner flange part at the time of rectangular tube drawing, the 45 degree direction material is less likely to flow into the 0 degree direction and 90 degree direction with respect to the rolling direction corresponding to the straight side direction or the short side direction. It is effective to increase the amount of material inflow. Among the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction, the higher the TS × (TS / YS) in the 45 degree direction with respect to the rolling direction in which the material does not easily flow in the corner flange portion at the time of rectangular tube drawing, the higher The molding height becomes better.

  The elongation of the aluminum alloy foil can be adjusted as appropriate by changing the average crystal grain size, strength, and the like. The higher the value, the better the formability. Specifically, it is preferable that the elongation values in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction are 10% or more, particularly 12% or more, because the formability becomes good.

  The thickness of the aluminum alloy foil is arbitrary, and can be appropriately adjusted according to the use and molding conditions, but is generally preferably 10 to 100 μm. When an aluminum alloy foil having a thickness of less than 10 μm is produced, pinholes or breakage during cold rolling is likely to occur, and production efficiency is likely to decrease. On the other hand, if the thickness exceeds 100 μm, the overall thickness becomes too large when the molded packaging material is used, and it is difficult to reduce the size of the molded packaging material to be obtained.

(3) Manufacturing method of aluminum alloy foil The aluminum alloy foil of this embodiment is Fe: 0.8-2.0 mass%, Si: 0.05-0.2 mass%, Cu: 0.2-0.5 mass%. A step of heat-treating an aluminum alloy ingot composed of Al and unavoidable impurities at 550 ° C. or more and 620 ° C. or less for 1 hour or more, a step of performing hot rolling and cold rolling after the heat treatment, Before or during the cold rolling, the step of performing the intermediate annealing held at 300 to 450 ° C., and the cold rolling at 93 to 99% from the intermediate annealing to the final foil thickness is performed. It is manufactured by performing final annealing after the process and the cold rolling. Hereinafter, the manufacturing method of the aluminum alloy foil of this embodiment is demonstrated in detail.

  In the manufacturing method of the present embodiment, an aluminum alloy ingot is obtained by a semi-continuous casting method after melting an aluminum alloy having the above composition. Then, the homogenization process which hold | maintains an aluminum alloy ingot at 550-620 degreeC for 1 hour or more is performed. In the homogenization treatment by heat treatment, the Fe-based precipitates are increased in size and distributed more sparsely to reduce the amount of Fe solid solution. If the homogenization temperature by heat treatment is less than 550 ° C. and the holding time is less than 1 hour, the Fe-based precipitates are not sufficiently coarsened, so the amount of Fe solid solution is high, and fine Fe-based precipitates are also present. Many. Therefore, the yield strength is increased, and the value of TS × (TS / YS) is less than 200 MPa in the tensile strength TS in the 45 ° direction with respect to the rolling direction and the 0.2% yield strength YS, and the formability is deteriorated. Moreover, the segregation formed in the casting and existing in the ingot may not be sufficiently eliminated. When the homogenization temperature by heat treatment exceeds 620 ° C., the ingot may be locally melted, which may be undesirable in production. In addition, since a very small amount of hydrogen gas mixed at the time of casting tends to swell out on the surface of the material, it may not be preferable. In order to increase the size of the Fe-based precipitate and distribute it sparsely, the homogenization temperature by heat treatment is preferably 580 ° C. or more and 615 ° C. or less.

  After the homogenization treatment by the heat treatment, hot rolling may be started after the ingot is cooled to 400 ° C. or more and 500 ° C. or less. By performing this cooling, the amount of Fe solid solution can be reduced while growing the size of the Al—Fe-based precipitate. Thereby, the yield strength of aluminum alloy foil can be reduced. When the starting temperature of hot rolling is less than 400 ° C., the amount of fine Al—Fe-based precipitates increases so much that the yield strength is improved. Therefore, in the tensile strength TS in the 45 degree direction and the 0.2% proof stress YS with respect to the rolling direction, the value of TS × (TS / YS) is less than 200 MPa, and the formability deteriorates. When the start temperature of hot rolling exceeds 500 ° C., the amount of Fe dissolved in the aluminum alloy foil increases, so that the proof stress is improved. Therefore, in the 45 degree tensile strength TS and 0.2% proof stress YS with respect to the rolling direction, the value of TS × (TS / YS) is less than 200 MPa, and the formability may be reduced.

  Hot rolling is performed after the homogenization process by the said heat processing and completion | finish of cooling. The end temperature of hot rolling is preferably 250 to 400 ° C. in order to recrystallize the aluminum alloy plate as much as possible. In order to increase the recrystallization rate of the aluminum alloy sheet after hot rolling, it is more preferable to terminate at 300 ° C. or higher. Further, cold rolling is performed after the hot rolling. This cold rolling can be performed by a known method and is not particularly limited.

  Moreover, in the manufacturing method of this embodiment, it is necessary to perform intermediate annealing at 300 to 450 degreeC before the start of the said cold rolling or in the middle. By performing the intermediate annealing, the aluminum alloy sheet is recrystallized to improve the rollability. In particular, since the aluminum alloy plate contains Cu in addition to Fe and Si, deformation resistance during cold rolling increases. Therefore, it is necessary to perform intermediate annealing once in the course of cold rolling from hot rolling to the final foil thickness in order to prevent sheet breakage during cold rolling. The time for performing the intermediate annealing is not particularly limited, but is preferably 1 hour or longer in order to recrystallize the aluminum alloy sheet. Further, if the intermediate annealing is not performed, the cold rolling rate until the final foil thickness is increased, so that the amount of strain accumulated during the cold rolling increases, and sheet breakage and cracking are likely to occur. If the temperature of the intermediate annealing is less than 300 ° C., the crystal grains are likely to be coarsened during the final annealing, the uniformity of deformation is hindered, and the formability may be lowered. On the other hand, when the temperature of the intermediate annealing exceeds 450 ° C., Fe re-dissolves, and the value of the proof stress YS increases. Thereby, since the value of TS × (TS / YS) in the 45 degree direction with respect to the rolling direction becomes small, the formability may deteriorate.

  In the manufacturing method of the present embodiment, it is recommended that cold rolling from intermediate annealing to final foil thickness be performed at a cold rolling rate of 93 to 99%. Since the aluminum alloy foil of this embodiment contains Cu in addition to Fe and Si, recrystallization during the final annealing is difficult due to the influence of Cu dissolved in the aluminum alloy foil. In order to finely recrystallize the aluminum alloy foil during the final annealing, it is important to control the crystal grain size and the 0.2% proof stress value by adjusting the cold rolling rate. If the cold rolling rate is less than 93%, the amount of strain accumulated during cold rolling decreases, and the crystal grains after the final annealing increase, resulting in a decrease in strength and a decrease in formability. On the other hand, if the cold rolling rate exceeds 99%, the amount of accumulated strain increases, the crystal grain size may be less than 7 μm, and the value of 0.2% proof stress YS greatly increases. As a result, the value of TS × (TS / YS) in the 45 degree direction with respect to the rolling direction becomes less than 200 MPa, and the formability deteriorates.

  After the end of cold rolling, final annealing is performed to make the aluminum alloy foil a complete soft foil. The final annealing is preferably performed at 250 to 400 ° C. for 5 hours or more from the viewpoint of completely volatilizing the rolling oil while completely recrystallizing the aluminum alloy foil. When the final annealing temperature is less than 250 ° C., the aluminum alloy foil may not be completely recrystallized, so that a soft foil may not be obtained. On the other hand, if the final annealing temperature exceeds 400 ° C., the crystal grains are coarsened during annealing, so that the formability may be lowered. If the holding time at the time of final annealing is less than 5 hours, the rolling oil used in the foil rolling does not sufficiently evaporate, so that the wettability of the foil surface is reduced and the adhesion between the aluminum alloy foil and the resin film to be laminated is reduced. Tends to decrease. It is desirable to carry out the heating rate during the final annealing at 50 ° C./hr or less. When the rate of temperature rise exceeds 50 ° C./hr, some of the crystal grains are coarsened, so that non-uniform deformation is likely to occur at the time of rectangular tube drawing, and formability is reduced.

<Molded packaging material>
The aluminum alloy foil of the present embodiment can be used as a part or all of the molded packaging material. The molded package in the present embodiment refers to the molded package material of the present embodiment, which is formed by processing various products such as batteries and PTP for packaging. Examples include ion battery materials (including electrodes, separators, electrolytic solutions, etc.).

  The molded package material of the present embodiment may be composed of a single layer of aluminum alloy foil or a plurality of layers including an aluminum alloy foil layer. In the case of a plurality of layers, it is not particularly limited, but it is necessary that at least an aluminum alloy foil is provided as a constituent element. Specifically, as shown in FIG. 1, the molded package material 1 can be exemplified by a laminate of a heat sealing layer 3 and a synthetic resin film 4 on an aluminum alloy foil 2. The synthetic resin film 4 is used to improve the moldability of the molded packaging material, to protect the aluminum alloy foil 2 which is the main material of the molded packaging material, or to enable printing. 2 is attached to one side. As such a synthetic resin film 4, a polyester film, a nylon film, or the like can be used. The molded packaging material of this embodiment can be used for a packaging material for a secondary battery or a pharmaceutical packaging container. In particular, when it is used as a packaging material for a secondary battery, a heat-resistant polyester film is used as the synthetic resin film 4 because it is necessary to heat and dissipate various battery members housed in the packaging material. Is preferred.

  As shown in FIG. 2, the heat sealing layer 3 is for sealing the end 21 of the molded package 20. As the heat sealing layer 3, a conventionally known heat-fusible synthetic resin can be used. In particular, any material may be used as long as it has excellent adhesion to the aluminum alloy foil 2 used in the present embodiment and can protect the contents, such as an unstretched polypropylene film, a biaxially stretched polypropylene film, and maleic acid. It is preferable to use a modified polyolefin.

  When the molded package material of the present embodiment has a plurality of layers, the synthetic resin film 4, the aluminum alloy foil 2 used in the present embodiment, and the heat sealing layer 3 may be laminated in this order. If it satisfies the suitability of the contents, it is not particularly limited. For example, after placing an unstretched polypropylene film on one side of an aluminum alloy foil through an adhesive film, pressure bonding, and pasting the aluminum alloy foil and the film, on the other side of the aluminum alloy foil, An adhesive can be applied, and a synthetic resin film can be adhered thereon.

  The pressure bonding between the aluminum alloy foil and the polypropylene film is generally performed under heating. Heating conditions are about 160-240 degreeC. The pressure bonding conditions are a pressure of 0.05 to 0.2 MPa and a time of about 0.5 to 3 seconds, but these conditions can be adjusted as appropriate. As the adhesive for the synthetic resin film 4, a conventionally known adhesive is used, and for example, a urethane-based adhesive or the like is used.

  The molded packaging material of the present embodiment can be molded by a known method, and the molding method is not particularly limited, but in particular, deep drawing can be suitably used. Here, an example of the method of obtaining the shaping | molding packaging body 20 using the shaping | molding packaging body material which concerns on this embodiment is shown. First, a molded packaging material is cut into a desired size to obtain a packaging material having a desired shape. This packaging material is deep-drawn so that the central portion is a concave portion, the peripheral portion is a flat portion, and the heat sealing layer side is an inner surface. Using a packaging material that has been deep-drawn and a substantially flat packaging material, the peripheral heat-sealing layers are bonded to each other. And a part of peripheral part is left and the other peripheral part is heat-sealed, and the molded package 20 is obtained. If the molded package 20 is used as a secondary battery exterior material, as shown in FIG. 2, the positive electrode current collector 5, the positive electrode 6, the separator 7, the negative electrode 8, and the negative electrode current collector are disposed in the recesses of the molded package 20. A secondary battery can be manufactured by storing a plurality of units consisting of 9 and impregnating with an electrolyte solution. Furthermore, a secondary battery can be manufactured in accordance with a known method such as heat-sealing the bag mouth again so that the lead wire extending from the secondary battery body is exposed to the outside.

  According to the secondary battery of the present embodiment, since the molded packaging material provided with the aluminum alloy foil having the above-mentioned good formability is used, the deep recess can be formed deeper than before. As a result, a secondary battery having a large amount of battery material can be formed, so that a secondary battery with a high charge capacity or high output that can withstand long-term use can be obtained.

  Even when a pharmaceutical packaging container is obtained using the molded packaging material of the present embodiment, the above-described method can be adopted as the molding method. For example, in the case of PTP, medicines (tablets, capsules, etc.) can be stored and used as pharmaceutical packaging containers. The pharmaceutical packaging container of this embodiment can be manufactured by a known method, and the manufacturing method is not particularly limited.

  According to the pharmaceutical packaging container of this embodiment, since the molded packaging material provided with the aluminum alloy foil having the above-mentioned good formability is used, deep drawing can be performed. Thereby, the pharmaceutical packaging container which can achieve reduction of a shaping | molding packaging body material can be obtained. Moreover, according to the pharmaceutical packaging container of this embodiment, since the average crystal grain size of the aluminum alloy foil is small, non-uniform deformation hardly occurs at the time of deep drawing molding, and there are few cracks at the corners of the molded packaging body. For this reason, it is difficult for water vapor from the outside to enter the molded package, and the long-term quality controllability of the tablet-like contents that require water vapor barrier properties during storage is also excellent.

  As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and various structures other than the above are also employable.

  For example, in the above-described embodiment, the molded package material is used for a secondary battery or a pharmaceutical package. However, the material is not particularly limited, and may be used for other packaging applications. For example, it can also be used as a molded battery material for primary batteries, not secondary batteries. In this way, the deep recess can be formed deeper than before, and a primary battery outer packaging material with a large amount of battery material can be formed, thus achieving a capacity and high output that can withstand long-term use. A primary battery can be obtained.

  EXAMPLES Hereinafter, although the Example and comparative example of this invention are shown and this invention is demonstrated concretely, this invention is not limited to these Examples, It can be expanded in the range of the technical idea of this invention.

  An aluminum ingot having the composition described in Table 1 was prepared, and subjected to the homogenization treatment, cooling, hot rolling, cold rolling, foil rolling and final annealing described in Table 1, and an aluminum alloy foil having a thickness of 40 μm Got. The obtained aluminum alloy foil was measured for tensile strength, 0.2% yield strength and elongation at 0 °, 45 ° and 90 ° with respect to the rolling direction, and are shown in Table 2. Table 2 also shows the presence / absence of cracking during the cold rolling until the final foil thickness and the measured value of the average grain size. In addition, an actual laminate composite material for battery exterior materials was prototyped and a rectangular tube drawing test described later was performed. The results are shown in Table 2.

  The tensile strength of the aluminum alloy foil was a strip-shaped sample piece having a width of 10 mm, a distance between chucks of 50 mm, and a tensile speed of 10 mm / min. Measured by conducting a tensile test at. The stress obtained by dividing the maximum load applied to the strip-shaped sample piece by the cross-sectional area of the sample piece before the test was calculated as the tensile strength. The 0.2% proof stress is a parallel line from the point of permanent strain of 0.2% on the elongation axis with respect to this straight line in the elastic region indicated by the straight line of the initial rise in the load-elongation curve diagram. The load at the point where the parallel line intersects the load-elongation curve, that is, the point corresponding to the yield point of the steel material or the like, was obtained by dividing by the cross-sectional area of the specimen before the test. Elongation is [(L-50) / 50] × 100, where L (mm) is the distance between chucks when the strip-shaped sample piece is broken by the same measurement method as in the case of tensile strength. It is calculated.

  Next, the following experiment was conducted in order to test the degree of deep drawability of the molded packaging material using the aluminum alloy foil according to the example. That is, an organosol consisting of 15 parts by weight of maleic anhydride-modified polypropylene having an average particle size of 6 to 8 μm and 85 parts by weight of toluene was applied to one side of each aluminum alloy foil obtained in the examples, and the condition was 200 ° C. for 20 seconds. And dried to obtain an adhesive film having a thickness of 2 μm. Next, a 40 μm-thick polypropylene film was pressure-bonded to the surface of the adhesive film under pressure-bonding conditions of a temperature of 200 ° C., a pressure of 0.2 MPa, and a time of 1 second. Finally, a biaxially stretched nylon having a thickness of 25 μm was adhered to the other surface of the aluminum alloy foil (the surface to which the polypropylene film was not adhered) via a urethane adhesive to obtain a molded packaging material. .

  The molded packaging material was cut into a size of 120 mm × 100 mm and used as a sample for a rectangular tube drawing test. Using a punch with a length of 60 mm, a width of 40 mm, a shoulder R and a corner R of 1.5 mm, a square tube drawing test was conducted at a wrinkle suppressing force of 3.92 kN. The molding height is increased from 1.0 mm to 0.5 mm, and the above-mentioned square tube drawing molding test is performed at each molding height 5 times. The maximum molding height at which no pinholes or cracks occur in all 5 times. The results are shown in Table 2.

  The average crystal grain size of the aluminum alloy foil was measured by a cutting method as follows. First, each obtained aluminum alloy foil was electropolished at a voltage of 20 V using a 20 volume% perchloric acid + 80 volume% ethanol mixed solution of 5 ° C. or less. Then, after washing with water and drying, an anodized film was formed at a voltage of 20 V in a mixed solution of 50 vol% phosphoric acid + 47 vol% methanol + 3 vol% hydrofluoric acid at 25 ° C. or less. Thereafter, the crystal grains were observed with polarized light with an optical microscope and photographed. From the photograph taken, the average crystal grain size was measured by a cutting method. The cutting method is a method of calculating the average crystal grain size by counting how many crystal grains are present in a certain line segment and dividing the line segment by the number.

  As is clear from the above results, the aluminum alloy foils according to Examples 1 to 19 have a higher molding height at the time of rectangular tube drawing than the aluminum alloy foils according to Comparative Examples 20 to 37, and the moldability is improved. It shows that it is excellent. Therefore, the molded packaging material obtained using the aluminum alloy foils according to Examples 1 to 19 can be well formed by deep drawing and is suitable for packaging a relatively thick content. I understand. On the other hand, it is clear that the aluminum alloy foils according to Comparative Examples 20 to 37 have a low molding height at the time of rectangular tube drawing and have poor moldability.

  In Comparative Example 20, the tensile strength in the 45-degree direction and the 90-degree direction is low, the value of TS × (TS / YS) in the 45-degree direction is low, and the material is less likely to flow from the flange portion during rectangular tube drawing, Molding height did not improve.

  In Comparative Example 21, the value of TS × (TS / YS) in the 45-degree direction was low and the average crystal grain size was large, so that the molding height was not improved.

  In Comparative Example 22, the TS × (TS / YS) value in the 45-degree direction was low and the average crystal grain size was large, so that the molding height was not improved.

  In Comparative Example 23, the crystal grain size became too fine, the value of TS × (TS / YS) in the 45 degree direction was low, and the molding height was not improved. In addition, coarse intermetallic compounds were crystallized during casting, and cracks occurred during cold rolling.

  In Comparative Example 24, the tensile strength in the 45 ° direction was low, and the TS × (TS / YS) value in the 45 ° direction was low, so the molding height was not improved.

  In Comparative Example 25, the value of TS × (TS / YS) in the 45-degree direction was low, and the molding height was not improved.

  In Comparative Example 26, cracks occurred during cold rolling.

  In Comparative Example 27, the TS × (TS / YS) value in the 45-degree direction was low, and the material did not easily flow from the flange portion during square tube drawing, so the molding height did not improve.

  In Comparative Example 28, the value of TS × (TS / YS) in the 45 ° direction was low, and the material did not easily flow from the flange portion during square tube drawing, so the molding height did not improve.

  In Comparative Example 29, the value of TS × (TS / YS) in the 45-degree direction was low and the average crystal grain size was large, so that the molding height was not improved.

  In Comparative Example 30, since the value of TS × (TS / YS) in the 45-degree direction was low and the material did not easily flow from the flange portion during square tube drawing, the molding height was not improved.

  In Comparative Example 31, the value of TS × (TS / YS) in the 45-degree direction was low, and the molding height was not improved because the material did not easily flow from the flange portion during square tube drawing. Furthermore, cracks occurred during cold rolling.

  In Comparative Example 32, the value of TS × (TS / YS) in the 45-degree direction was low and the average crystal grain size was also large, and the molding height was not improved.

  In Comparative Example 33, the value of TS × (TS / YS) in the 45 ° direction was low, and the material did not easily flow from the flange portion during square tube drawing, so the molding height did not improve.

  In Comparative Example 34, since the aluminum alloy foil was not recrystallized, the molding height was not improved.

  In Comparative Example 35, the value of TS × (TS / YS) in the 45-degree direction was low, the average crystal grain size was large, and the molding height was not improved.

  In Comparative Example 36, the value of TS × (TS / YS) in the 45-degree direction was low, the average crystal grain size was large, and the molding height was not improved.

  In Comparative Example 37, the molding height decreased because the aluminum alloy foil was not recrystallized.

DESCRIPTION OF SYMBOLS 1 Molding packaging material 2 Aluminum alloy foil 3 Heat sealing layer 4 Synthetic resin film 5 Positive electrode collector 6 Positive electrode 7 Separator 8 Negative electrode 9 Negative electrode collector 20 Molding packaging body 21 End

Claims (7)

  Fe: 0.8-2.0 mass%, Si: 0.05-0.2 mass%, Cu: 0.2-0.5 mass%, the balance is made of Al and inevitable impurities, and the average crystal grain size Is an aluminum alloy foil characterized by being 7 to 20 μm.   The values of TS × (TS / YS) in the 45 degree direction when the tensile strength in the 0 degree, 45 degree, and 90 degree directions with respect to the rolling direction is 90 MPa or more, respectively, and the tensile strength TS and 0.2% proof stress YS. The aluminum alloy foil according to claim 1, wherein is 200 MPa or more.   A molded package material comprising the aluminum alloy foil according to claim 1. A synthetic resin film laminated on one side of the aluminum alloy foil;
A heat sealing layer laminated on the other side of the aluminum alloy foil;
The molded packaging material according to claim 3.   A battery comprising the molded package material according to claim 3.   A pharmaceutical packaging container comprising the molded packaging material according to claim 3 or 4. A method for producing the aluminum alloy foil according to claim 1 or 2,
Fe: 0.8 to 2.0 mass%, Si: 0.05 to 0.2 mass%, Cu: 0.2 to 0.5 mass%, aluminum alloy ingot consisting of Al and unavoidable impurities in the balance is 550 ° C or higher. A heat treatment at 620 ° C. or lower for 1 hour or longer;
A step of performing hot rolling and cold rolling after the heat treatment;
Before or during the cold rolling, performing an intermediate annealing to be held at 300 to 450 ° C .;
A step of performing cold rolling at a cold rolling rate of 93 to 99%;
Method for producing an aluminum alloy foil, which comprises obtaining a A aluminum alloy foil annealed, the.

Images