Die for drawing

Abstract

To provide a die for drawing which is excellent in moldability.SOLUTION: A die for drawing has a die 1 having a molding hole 11 opened on one surface side, and a punch 2 provided corresponding to the one surface side of the die 1, and draws a laminate material L having resin layers 62 and 63 provided on at least one surface side of a metal foil layer 61 by the punch 2 pressed-fitted into the molding hole 11 in a recess shape and molds a drawn article 5, in a state where the laminate material L is arranged on one surface of the die 1. An easy slip surface 22 is formed on the surface on the tip side of the punch in contact with the laminate material L. A coefficient of dynamic friction to the laminate material L in the easy slip surface 22 is set at 0.3 or less, and Vickers hardness of the easy slip surface 22 is set at 200 HV or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a deep-drawn molded product obtained using a laminate material including a metal foil layer and a resin layer as a molding material, such as packaging material for electricity storage modules, food containers, and packaging material for medicines such as blister packs, and to a die for drawing used in the manufacture of such products, a method for manufacturing a draw-drawn product, and a method for manufacturing packaging material for electricity storage modules. [Background technology]

[0002] Packaging materials (housings) as casings for storage modules (battery devices) of electric vehicles and the like are provided with spaces (battery storage recesses) for storing storage devices such as batteries. When producing packaging materials for such storage modules, a technique has been proposed that uses a drawn product with recesses made of a laminate sheet (laminate material) as a molding material. The recesses (battery storage sections) of this packaging material are formed by cold forming or the like, and it is desired to increase the spatial capacity of the battery storage recesses to accommodate high-capacity or high-power storage devices. In order to increase the spatial capacity of the battery storage recesses of the packaging material, a method for improving the formability of the packaging material can be mentioned. In particular, when producing a double-cup-shaped molded product in which two battery storage recesses are simultaneously formed in one laminate material, molding defects such as wrinkles are likely to occur between the two drawn sections, and it is necessary to further improve the formability.

[0003] Conventionally, when molding a molded product using a laminate material as a molding material, in order to improve moldability, it is common to add a filler to the protective layer (resin layer) of the laminate material as shown in Patent Document 1 below, or add a lubricant to the heat-sealing layer (resin layer) as shown in Patent Document 2 below, thereby modifying the surface of the laminate material itself and controlling the slipperiness of the laminate material surface to improve moldability. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6828777 [Patent Document 2] Patent No. 6808916 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the conventional molding methods shown in Patent Documents 1 and 2 above had the problem that the state of surface modification varied depending on the laminate material or the part (location) of the laminate material, making it difficult to obtain stable moldability.

[0006] Furthermore, since there are many different types of laminate materials used as molding materials, not all of them are manufactured under the same processing conditions. For example, there is a problem that good moldability cannot be obtained depending on the processing conditions such as aging.

[0007] On the other hand, a die for drawing is used to draw laminate materials, and it goes without saying that there is a strong desire to prevent the die from deteriorating in a short period of time due to repeated use and to improve its durability.

[0008] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a die for drawing that can stably obtain good formability while ensuring sufficient durability, a method for manufacturing a draw-molded product, and a method for manufacturing a packaging material for an energy storage module. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention comprises the following means.

[0010] [1] A die having a forming hole that opens to one side and a punch provided corresponding to the one side of the die, in which a laminate material having a metal foil layer and a resin layer provided on at least one side of the die is placed on one side of the die, and the laminate material is pressed into the forming hole by the punch to form a drawn product, A slippery surface is formed on the tip side surface of the punch that comes into contact with the laminate material, A die for drawing, characterized in that the coefficient of dynamic friction of the slippery surface with respect to the laminate material is set to 0.3 or less, and the Vickers hardness of the slippery surface is set to 200 HV or more.

[0011] [2] A die for drawing as described in the preceding paragraph 1, wherein at least the outer peripheral edge portion of the tip side surface of the punch is formed into the easy-slip surface.

[0012] [3] The punch comprises a punch body and a lubricating coating provided so as to cover the tip surface of the punch body, and the lubricating surface is formed by the surface of the lubricating coating.

[0013] [4] The die for drawing according to the preceding paragraph 3, wherein the easy-slip coating is made of a diamond-like carbon (DLC) coating.

[0014] [5] The die for drawing according to the above item 3 or 4, wherein the thickness of the easy-slip coating is set to 0.1 μm to 3 μm.

[0015] [6] The Vickers hardness of the inner peripheral surface of the forming hole of the die is set to 200 HV or more; 6. The die for drawing according to any one of items 1 to 5 above, wherein the dynamic friction coefficient of the inner peripheral surface of the forming hole of the die with respect to the laminate material is set to be greater than the dynamic friction coefficient of the smooth surface.

[0016] [7] A method for producing a drawn product, comprising the steps of: using a die for drawing as described in any one of items 1 to 6 above to draw a laminate material into a concave shape, thereby producing a drawn product having a concave portion formed therein.

[0017] [8] A method for producing a packaging material for a storage module, comprising the steps of: using a drawing die as described in any one of items 1 to 6 above to draw a laminate material into a concave shape, thereby producing a packaging material for a storage module having a concave portion formed therein. Effect of the Invention

[0018] According to the drawing die of the invention [1], a slippery surface is formed on the surface of the punch tip side to reduce the coefficient of dynamic friction of the surface, so that the laminate material deforms smoothly along the surface of the punch tip side during forming, and there is no problem such as tensile stress acting locally concentratedly, so that the laminate material can be precisely and accurately processed into the desired shape, and good formability can be stably obtained. In addition, since sufficient strength is ensured on the surface of the punch tip side, durability can be improved.

[0019] According to the die for drawing of the invention [2], a slippery surface is formed on the outer peripheral edge of the surface of the tip side of the punch, which corresponds to the part of the laminate material where stress is particularly likely to concentrate during molding, thereby further improving formability.

[0020] According to the drawing dies of inventions [3] to [5], a slippery surface can be easily formed simply by forming a slippery coating on the punch body, which in turn makes it possible to manufacture the die simply and efficiently.

[0021] According to the drawing die of invention [6], the gripping force on the laminate material on the inner surface of the die can be secured, thereby preventing the laminate material from shifting position during molding and more reliably achieving stable moldability.

[0022] According to the manufacturing method of the draw-molded product of the invention [7], since the draw-molding die of the above invention is used, the same effects as those described above can be obtained.

[0023] According to the method for manufacturing a packaging material for a storage module of the invention [8], since the die for drawing of the above invention is used, the same effects as those described above can be obtained. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a front cross-sectional view showing a draw-forming die according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a bottom view (one-sided view) showing a die of the draw-forming die of the first embodiment. [Diagram 3] FIG. 3 is a plan view showing a punch of the draw-forming die according to the first embodiment. [Figure 4] FIG. 4 is a front sectional view for explaining the configuration of the drawing punch of the first embodiment. [Figure 5A] FIG. 5A is a cross-sectional view showing a schematic diagram of a laminate material as a forming material by the draw-forming die of the first embodiment. [Figure 5B] FIG. 5B is a perspective view showing a draw-formed product formed by the draw-forming die of the first embodiment. [Figure 6] FIG. 6 is a front sectional view for explaining the configuration of a modified example of the drawing punch of the first embodiment. [Figure 7] FIG. 7 is a front cross-sectional view showing a draw-forming die according to a second embodiment of the present invention. [Figure 8] FIG. 8 is a bottom view (one-sided view) showing a die of the draw-forming die of the second embodiment. [Figure 9] FIG. 9 is a plan view showing a punch of a draw-forming die according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] First Embodiment Fig. 1 is a front cross-sectional view showing a draw-forming die according to a first embodiment of the present invention. As shown in the figure, the draw-forming die according to the first embodiment includes a die 1, a punch 2, and a blank holder 3, and forms a draw-formed product 5 having a recess 51 formed therein as shown in Fig. 5B by drawing a forming material, which is a laminate material (laminate sheet) L, into a concave shape as shown in Fig. 5A.

[0026] 5A, the laminate material L used as a molding material in this embodiment includes a metal foil layer 61 such as aluminum foil, a heat-sealable resin layer 62 laminated on one surface (inner surface) of the metal foil, and a heat-resistant resin layer 63 laminated on the other surface (outer surface) of the metal foil layer. In the draw-formed product 5 of this embodiment, the heat-sealable resin layer (one-surface-side resin layer) 62 on one surface side of the laminate material L is molded to be disposed on the inner peripheral surface side of the recess 51.

[0027] In this embodiment, a three-layer structure is used as the laminate material L, but the present invention is not limited thereto, and a two-layer structure or a structure of four or more layers can be used as long as a resin layer is provided on at least one side of the metal foil layer. However, in the present invention, it is preferable to use a three-layer structure including a metal foil layer and having a resin layer on both one side (inner side) and the other side (outer side).

[0028] As shown in Figs. 1 and 2, a die 1 of a drawing metal mold has a forming hole 11 that penetrates in the axial direction (the vertical direction in Fig. 1) and has a rectangular shape when viewed from below (in a plan view).

[0029] A blank holder 3 is provided on one surface side (the lower surface side in FIG. 1) of the die 1. The blank holder 3 has a punch insertion hole 31 that penetrates in the axial direction and has a rectangular shape in a plan view corresponding to the forming hole 11 of the die 1. The blank holder 3 is configured so that it can be moved toward and away from one surface of the die 1 with the punch insertion hole 31 axially aligned with the forming hole 11. This allows the laminate material L, as a forming material, to be held by clamping the outer periphery of the laminate material L between the die 1 and the blank holder 3 with the middle part of the laminate material L positioned corresponding to the forming hole 11 of the die 1.

[0030] 1 and 3, the punch 2, which is disposed corresponding to one surface side (lower surface side) of the die 1, is formed in a rectangular shape in a plan view corresponding to the forming hole 11 of the die 1, and is supported by a movable shaft 25 so as to be movable along its axis with its axis aligned with the forming hole 11. When the movable shaft 25 moves along its axis, the punch 2 is configured to be pressed into the forming hole 11 of the die 1 from its one surface side (lower surface side) through a punch insertion hole 31 of the blank holder 3.

[0031] 5A is clamped between the punch 2 and the blank holder 3, and the punch 2 is pressed into the forming hole 11, whereby the laminate material L is drawn into a concave shape from one surface side (the lower surface side) by the punch 2 to produce a drawn product 5. As described above (see FIG. 5B), this drawn product 5 has a flange portion 52 formed to protrude outward from the opening edge portion of the recess 51, and the flange portion 52 is cut to an appropriate size and used, for example, as a packaging material (housing) that is the casing of the electricity storage module.

[0032] The punch 2 in the drawing die of this embodiment has a tip side on the side corresponding to the forming hole 11 of the die 1 (the upper surface side in Fig. 1), and the tip side surface (tip surface and outer peripheral side surface) is formed into a slippery surface 22. Specifically, as shown in Fig. 4, the punch 2 is composed of a punch body 20 and a slippery coating (slippery layer) 21 that is provided continuously over the entire area from the tip surface to the outer peripheral side surface of the punch body 20 and covers this entire area, and the slippery surface 22 is formed by the surface of this slippery coating 21.

[0033] In Figure 4, the thickness of the easy-to-smooth coating 21 is exaggerated to make it easier to understand the invention, but in reality the thickness of the easy-to-smooth coating 21 is negligible, and the size of the punch 2 and the size of the punch body 20 can be considered to be approximately the same (the same applies to Figure 6 below).

[0034] In this embodiment, the dynamic friction coefficient of the slippery surface 22 against the heat-sealable resin layer 62 on one side (inner side) of the laminate material L must be set to 0.3 or less, and is preferably set to 0.2 or less. In other words, when the dynamic friction coefficient of the slippery surface 22 of the punch 2 is set low as the above-mentioned specified value, regardless of the surface state of the laminate material L, the outer surface (slippery surface 22) of the punch 2 does not adhere to the heat-sealable resin layer 62 of the laminate material L during molding, but rather slides moderately against it. During molding, the laminate material L as a molding material is deformed so as to smoothly wrap around along the surface of the punch tip side, and the tensile stress acting on the laminate material L is appropriately distributed, preventing a large amount of deformation stress from being concentrated locally. Therefore, the laminate material L can be processed into a desired shape without difficulty, and good moldability can be stably obtained.

[0035] In the present invention, the easy-slip coating 21 may be formed on at least a part of the tip surface of the punch 2 which is the surface that comes into contact with the laminate material L.

[0036] However, in the present invention, since stress tends to concentrate in the laminate material L at a position corresponding to the outer peripheral edge (corner between the tip surface and the outer peripheral side) on the tip surface of the punch 2 during forming, it is preferable to form at least this corner portion as the easy-slip surface 22. For example, as shown in FIG. 6, it is also possible to adopt a punch 2 in which an easy-slip coating 21 is formed only on the outer peripheral edge of the tip surface of the punch body 20. Even when this punch 2 is used, the laminate material L can be processed smoothly by drawing as described above, and good formability can be stably obtained. Furthermore, when the easy-slip coating 21 is partially formed only on the outer peripheral edge of the tip surface of the punch, the formation area of ​​the easy-slip coating 21 can be reduced, which reduces costs, and the easy-slip coating 21 can be formed efficiently and easily, and the punch 2 can be produced efficiently and easily at low cost.

[0037] In the punch 2 shown in FIG. 6, a recess 26 is formed in the center of the tip surface of the punch body 20 for the purpose of venting air, etc.

[0038] In this embodiment, suitable examples of the type (coating type) of the easy-slip coating 21 include a DLC (diamond-like carbon) coating, a nickel-fluororesin co-deposited coating, a fluororesin-impregnated chrome plating coating, etc., and among these, it is particularly preferable to use a DLC coating.

[0039] DLC film formation methods that can be used include plasma CVD, ionization deposition, sputtering, and vacuum arc deposition, with plasma CVD and vacuum arc deposition being preferred.

[0040] In addition, as a method for forming the nickel-fluororesin eutectoid coating and the fluororesin-impregnated chromium plating coating, a plating process can be used.

[0041] In this embodiment, the thickness of the easy-slip coating 21 is preferably adjusted to 0.1 μm to 10 μm. In particular, in the case of a DLC coating, it is preferably adjusted to 0.1 μm to 3 μm. If this film thickness is too thin, sufficient strength and sufficient slipperiness cannot be ensured, and there is a risk of reduced durability and reduced moldability. Furthermore, if the film thickness is too thick, it may have an adverse effect on the dimensional accuracy of the mold, making it difficult to produce a highly accurate molded product, and there is a risk of increased costs due to the increased use of the coating material.

[0042] In this embodiment, the Vickers hardness (based on the "Vickers measurement method" of JIS Z2244:2009) of the easy-slip surface 22 of the punch 2 is set to 200HV (kgf / mm 2 ) In other words, when the strength of the easy-slip surface 22 is set high like the above specified value, the punch 2 can have sufficient strength against press working (drawing), deterioration in a short period due to repeated use of the die can be effectively prevented, durability can be improved, and ultimately costs can be reduced.

[0043] For reference, the Vickers hardness of the tip surface of conventional punch 2 is 300HV (kgf / mm 2 )~500HV(kgf / mm 2 ) is set at about

[0044] On the other hand, in this embodiment, the punch body 20 is made of an easy-to-machine steel material such as pre-hardened steel or carbon tool steel. The punch 2 is formed by forming the easy-slip coating 21 on the surface of the punch body 20 made of such a steel material as described above.

[0045] In this embodiment, the inner peripheral surface of the forming hole 11 of the die 1 also needs to have a certain degree of slipperiness with respect to the laminate material L, but it is preferable to prioritize grip over slipperiness so that the laminate material L does not become displaced during forming. Therefore, there is no need to intentionally reduce the dynamic friction coefficient with respect to the laminate material L on the inner peripheral surface of the forming hole of the die 1, and further, considering the increase in cost due to film formation and the decrease in dimensional accuracy due to film formation, it is better not to form a coating such as the easy-slip coating 21 on the die 1 side.

[0046] Specifically, the coefficient of dynamic friction between the inner peripheral surface of the forming hole of the die 1 and the heat-resistant resin layer (outer surface side resin layer) 63 of the laminate material L is preferably 0.4 to 1.5 (0.4 to 1.5), and more preferably 1 or less.

[0047] In particular, in this embodiment, the kinetic friction coefficient of the inner circumferential surface of the forming hole of the die 1 is set to be greater than the kinetic friction coefficient of the slippery surface 22 of the punch 2. In other words, when the kinetic friction coefficient of the inner circumferential surface of the forming hole of the die 1 is "μd" and the kinetic friction coefficient of the slippery surface 22 of the punch 2 is "μp", it is preferable to establish the relationship "μd>μp".

[0048] Here, the dynamic friction coefficient of the inner peripheral surface of the die 1 and the slippery surface 22 of the punch 2 can be measured in accordance with JIS K7125. Since the die 1 and the punch 2 have a three-dimensional shape, a test piece is prepared by forming a coating (e.g., a slippery coating) under a predetermined condition on the dynamic friction coefficient measurement surface of a die steel having a length of 80 mm, a width of 200 mm, and a thickness of 2.5 mm, as required. On the other hand, as a mating material of the test piece, a sliding piece is prepared by wrapping a laminate material around the measurement target surface so that the measurement target surface is the outer surface, as required. Then, the dynamic friction coefficient of the sliding piece against the measurement surface of the test piece is measured in accordance with JIS K7125. The dynamic friction coefficient is similarly measured in the examples and comparative examples described later (however, in Comparative Examples 1 and 3, no coating is formed on the test piece on the punch side, and in Examples 1, 3 to 6 and Comparative Examples 1 and 2, no coating is formed on the test piece on the die side).

[0049] In this embodiment, the die 1 has a Vickers hardness (based on the "Vickers hardness test method" of JIS Z2244:2009) of 200HV (kgf / mm 2 In this case, sufficient strength can be ensured against press working (drawing), deterioration in a short period due to repeated use of the die can be effectively prevented, durability can be improved, and costs can be reduced.

[0050] As described above, in the die for drawing of this embodiment, a slippery surface 22 is formed on the surface of the punch tip side to reduce the dynamic friction coefficient of the surface of the punch tip side. As a result, during forming, the laminate material L deforms so that it smoothly wraps around the surface of the punch tip side, and there is no problem in which deformation stresses such as tensile stress are concentrated locally. The laminate material L can be precisely and reliably processed into the desired shape, and good formability can be stably obtained.

[0051] Furthermore, in this embodiment, the easy-slip surface 22 can be easily formed by simply forming the easy-slip coating 21 on the surface of the punch body 20.

[0052] In addition, in this embodiment, sufficient strength is ensured in the inner peripheral surface of the die and the surface of the punch, so that durability can be improved and costs can be reduced.

[0053] Furthermore, in this embodiment, the dynamic friction coefficient μd of the inner surface of the die is set to be larger than the dynamic friction coefficient μp of the punch surface. This makes it possible to smoothly draw the laminate material L while preventing the laminate material L from shifting out of position during forming, thereby reliably producing a high-quality drawn product 5 with high dimensional accuracy.

[0054] In the above embodiment, a die 1 having a forming hole 11 penetrating therethrough is used, but this is not limited to this. In the present invention, a die having a forming hole formed in a recessed shape having a bottom wall (top wall) may also be used (the same applies to the second embodiment described below).

[0055] <Second embodiment> The draw-molding die of the first embodiment described above (see Figures 1 to 3) is a so-called single-cup mold that is designed to mold one draw-molded product 5 from one laminate material L by a single press operation, while the draw-molding die of the second embodiment, as shown in Figures 7 to 9, is a so-called double-cup mold that is designed to simultaneously mold two draw-molded products 5 from one laminate material L by a single press operation.

[0056] 7 to 9, in the drawing die of the second embodiment, two forming holes 11 are formed in the die 1 in a parallel arrangement with their short sides facing each other, and two punch insertion holes 31 are formed in a parallel arrangement in a blank holder 3 which can be attached to and detached from one surface (lower surface) of the die 1, corresponding to the two forming holes 11 of the die 1. Furthermore, two punches 2 are provided corresponding to the two forming holes 11 on one surface side (lower surface side) of the die 1.

[0057] The other configurations of the draw-forming die of this second embodiment are substantially similar to those of the draw-forming die of the first embodiment described above, so the same or corresponding parts are given the same reference numerals and duplicate explanations are omitted.

[0058] In the drawing die of the second embodiment, one sheet of laminate material L is placed across two forming holes 11 on the lower surface side of the die, and the laminate material L is clamped and held by the die 1 and blank holder 3. In this state, two punches 2 are pressed into the two forming holes 11 of the die 1 through the two punch insertion holes 31 of the blank holder 3, and the one sheet of laminate material L is drawn at two locations to form a drawn preform having two connected drawn portions (two drawn products 5). Then, the connected portion between the drawn portions of this drawn preform is cut to produce two independent drawn products 5.

[0059] The draw-forming die of the second embodiment can also provide the same effects as those of the first embodiment.

[0060] Furthermore, in the double-cup molding die of this embodiment, molding defects such as wrinkles are likely to occur at the junction between the two drawn portions of the drawn base material immediately after molding. However, the molding die of the second embodiment, like the first embodiment, has excellent formability and can effectively prevent molding defects such as wrinkles from occurring at the junction, making it possible to reliably obtain a high-quality drawn base material with high dimensional accuracy, and ultimately a high-quality drawn product 5.

[0061] Needless to say, the present invention can also be applied to a die for drawing in which three or more drawn portions are formed in one forming operation. EXAMPLES

[0062] A laminate material (laminate sheet) L as a molding material was prepared by the following steps (1) to (4).

[0063] (2) A chemical conversion treatment solution consisting of phosphoric acid, polyacrylic acid (acrylic resin), a chromium (III) salt compound, water, and alcohol is applied to both sides of a metal foil (metal foil layer) 61 having a thickness of 40 μm and made of an aluminum alloy of A8021-O specified in JIS H4160, and then dried at 180° C. to obtain a chromium deposition amount of 10 mg / m per side. 2 A conversion coating was formed.

[0064] (2) A biaxially oriented nylon film (25 μm) was laminated as a heat-resistant resin layer (other-side resin layer) 63 on the outer surface (other side) of the above-mentioned metal foil layer via a two-component curing urethane-based adhesive (2 μm).

[0065] (3) On the inner surface (one surface) of the above metal foil layer, a CPP film (40 μm) was laminated as a heat-sealable resin layer (one surface side resin layer) 62 via a two-component curing type olefin-based adhesive (2 μm).

[0066] (4) The laminate (laminate material) thus obtained was subjected to a heat aging treatment in a 40°C environment for 10 days to produce laminate material L as a molding material sample.

[0067] <Example 1> 1. Single cup mold A draw-forming die (single cup die) having the same configuration as the draw-forming die of the first embodiment shown in Figs. 1 to 3 was produced.

[0068] That is, the die 1 had one rectangular forming hole 11 with a short side Ld1 (see Figure 2) of 40.5 mm, a long side Ld2 of 60.5 mm, a corner curvature radius Rd2 of 2.25 mm, and an opening edge (shoulder) curvature radius Rd1 (see Figure 1) of 1 mm.

[0069] The punch body 20 had a short side Lp1 (see FIG. 3) of 40 mm, a long side Lp2 of 60 mm, a corner radius of curvature Rp2 of 2 mm, and a shoulder radius of curvature Rp1 (see FIG. 1) between the tip surface and the outer peripheral side surface of 1 mm.

[0070] A blank holder 3 having a punch insertion hole 31 slightly larger than the die forming hole 11 was prepared.

[0071] The die 1, punch body 20, and blank holder 3 were each produced by machining stainless steel.

[0072] [Table 1]

[0073] [Table 2]

[0074] A continuous easy-slip coating 21 was formed on the area (front surface of the tip side) from the tip face to the outer circumferential side face of the punch body 20. As shown in Table 1, this easy-slip coating 21 is composed of a DLC coating having a thickness of 1 μm, and was formed by high-frequency plasma CVD using a raw material gas based on butadiene gas.

[0075] In this way, the easy-slip coating 21 was formed on the surface of the punch body 20 to produce the punch 2. As shown in Table 1, the surface of this punch 2 (easy-slip surface 22 formed by the easy-slip coating 21) has a dynamic friction coefficient of 0.1 against the inner resin layer (thermally adhesive resin layer) of the laminate material L, and a Vickers hardness of 3000 HV.

[0076] As shown in Table 2, the die 1 has no coating formed thereon, and the dynamic friction coefficient of the inner surface of the forming hole with respect to the outer resin layer (heat-resistant resin layer) of the laminate material L is 0.5, and the Vickers hardness is 400 HV.

[0077] Using this single cup molding die attached to a 25t press machine as a molding device, multiple deep drawing operations were performed on a 100mm x 100mm laminate material (molding material) L with different molding heights (drawing depths). In other words, multiple deep drawing operations were performed with the molding height gradually increasing in 0.5mm increments starting from 5mm.

[0078] If a recess (drawn portion) with high dimensional precision was consistently obtained even when the forming height was 8 mm or more, it was evaluated as "◎". If a recess (drawn portion) with high dimensional precision was consistently obtained when the forming height was less than 8 mm (6 mm or more), it was evaluated as "◯". If a recess (drawn portion) with high dimensional precision was only obtained when the forming height was less than 6 mm, it was evaluated as "X".

[0079] As shown in the moldability (S) column of Table 1, the single-cup mold of Example 1 was rated as "Excellent."

[0080] In addition, after pressing (drawing) 1000 times in the single-cup molding die of Example 1, the surface condition of the punch 2 was observed. If no change was observed compared to before use (before pressing), it was evaluated as "Good", and if deterioration such as scratches or dents was observed compared to before use, it was evaluated as "Poor".

[0081] As shown in Table 1, the single-cup molding die of Example 1 obtained an evaluation result of "A".

[0082] 2.Double cup mold A draw-forming die (double-cup die) having the same configuration as the draw-forming die of the second embodiment shown in Figs. 7 to 9 was fabricated.

[0083] That is, the die 1 had two forming holes 11 arranged in parallel with their short sides facing each other, and each forming hole 11 had a short side Ld1 (see Figure 8) of 40.5 mm, a long side Ld2 of 60.5 mm, a corner radius of curvature Rd2 of 2.25 mm, and an opening edge (shoulder) radius of curvature Rd1 (see Figure 7) of 1 mm.

[0084] Two punch bodies 20 were prepared corresponding to the two forming holes 11 of the die 1. The short side Lp1 (see FIG. 9) of each punch body 20 was 40 mm, the long side Lp2 was 60 mm, the radius of curvature Rp2 of the corner portion was 2 mm, and the radius of curvature Rp1 (see FIG. 7) of the shoulder portion between the tip surface and the outer peripheral side surface was 1 mm. The distance between the two forming holes 11 of the die 1 was adjusted so that the distance L3 (see FIG. 9) between the two punch bodies 20 was 10 mm.

[0085] Furthermore, a DLC coating (easy-slip coating) 21 was formed from the tip face to the outer peripheral side face of the punch body 20 in the same manner as described above, thereby preparing the punch 2.

[0086] Further, the blank holder 3 has two punch insertion holes 31 formed corresponding to the two die forming holes 11 .

[0087] Other configurations of this double cup molding die are similar to those of the single cup molding die described above.

[0088] Using this double cup molding die attached to a 25t press as a molding device, laminate material (molding material) L measuring 100mm x 200mm was subjected to deep drawing molding multiple times by gradually increasing the molding height in 0.5mm increments as described above, and evaluation was performed in the same manner as described above.

[0089] As shown in the moldability (W) column of Table 1, the double-cup mold of Example 1 also obtained an evaluation result of "A".

[0090] When this double cup molding die was also evaluated for durability after 1000 presses in the same manner as the above single cup molding die, the same evaluation result of "good" was obtained as above.

[0091] <Example 2> As shown in Tables 1 and 2, a punch having a 3 μm thick DLC coating (slip-resistant coating 21) formed thereon and a dynamic friction coefficient on its surface of 0.05, and a die 1 having a 0.5 μm thick DLC coating formed on the inner circumferential surface of the molding hole and a dynamic friction coefficient of 0.15 against the outer resin layer (heat-resistant resin layer) of the laminate material L were used, and the rest of the process was the same as that of Example 1 above, to prepare a single cup molding die and a double cup molding die of Example 2.

[0092] The moldability and durability of the single cup molding die and double cup molding die of Example 2 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "◎" and the durability was rated as "○".

[0093] <Example 3> As shown in Tables 1 and 2, a punch having a DLC coating (slip-resistant coating 21) of 0.5 μm in thickness and a dynamic friction coefficient of its surface of 0.15 was used, and the rest of the process was the same as that of Example 1 above, to prepare a single cup molding die and a double cup molding die for Example 3.

[0094] The moldability and durability of the single cup molding die and double cup molding die of Example 3 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "◎" and the durability was rated as "○".

[0095] <Example 4> As shown in Tables 1 and 2, a 10 μm thick fluorine-containing nickel (Ni-PTFE) coating was formed by plating as the easy-slip coating 21, and a punch having a surface dynamic friction coefficient of 0.2 and a Vickers hardness of 300 HV was used. The single cup molding die and double cup molding die of Example 4 were produced in the same manner as in Example 1 above.

[0096] The moldability and durability of the single cup molding die and double cup molding die of Example 4 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "○" and the durability was rated as "○".

[0097] <Example 5> As shown in Tables 1 and 2, a 10 μm thick fluorine-containing nickel (Ni-PTFE) coating was formed by plating as the easy-slip coating 21, and a punch having a surface dynamic friction coefficient of 0.1 and a Vickers hardness of 800 HV was used. The single cup molding die and double cup molding die of Example 5 were produced in the same manner as in Example 1 above.

[0098] The moldability and durability of the single cup molding die and double cup molding die of Example 5 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "○" and the durability was rated as "○".

[0099] <Example 6> As shown in Tables 1 and 2, a 10 μm thick fluorine-containing chromium (Cr-PTFE) coating was formed by plating as the easy-slip coating 21, and a punch having a surface dynamic friction coefficient of 0.3 and a Vickers hardness of 500 HV was used. The single cup molding die and double cup molding die of Example 6 were produced in the same manner as in Example 1 above.

[0100] The moldability and durability of the single cup molding die and double cup molding die of Example 6 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "○" and the durability was rated as "○".

[0101] <Example 7> As shown in Tables 1 and 2, a punch having a 3 μm-thick DLC coating formed as a slip-resistant coating 21, with a surface dynamic friction coefficient of 0.1 and a Vickers hardness of 3000 HV, and a die 1 having a 3 μm-thick DLC coating formed on the inner surface of the forming hole, with an inner surface dynamic friction coefficient of 0.05 and a Vickers hardness of 3000 HV were used, and the rest of the process was the same as in Example 1 above, to prepare a single cup molding die and a double cup molding die of Example 7.

[0102] The moldability and durability of the single cup mold and the double cup mold of Example 7 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "◎" for the single cup mold and "○" for the double cup mold, and the durability was rated as "○" for both.

[0103] <Comparative Example 1> As shown in Tables 1 and 2, a punch having no coating, a surface dynamic friction coefficient of 0.5, and a Vickers hardness of 400 HV was used, and otherwise the same procedures were followed as in Example 1 above to prepare a single cup molding die and a double cup molding die for Comparative Example 1.

[0104] The moldability and durability of the single cup molding die and double cup molding die of Comparative Example 1 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "X" and the durability was rated as "O".

[0105] <Comparative Example 2> As shown in Tables 1 and 2, a punch having a 5 μm-thick fluororesin (PTFE) coating, a surface coefficient of dynamic friction of 0.1, and a Vickers hardness of 5 HV was used, and the rest of the process was the same as in Example 1 above, to prepare a single cup molding die and a double cup molding die for Comparative Example 2.

[0106] The moldability and durability of the single cup molding die and the double cup molding die of Comparative Example 2 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "◎" and the durability was rated as "×".

[0107] <Comparative Example 3> As shown in Tables 1 and 2, a single cup molding die and a double cup molding die of Comparative Example 3 were prepared in the same manner as in Example 1 above, except that a punch with no coating and a surface dynamic friction coefficient of 0.5 and a Vickers hardness of 400 HV and a die 1 with a DLC coating of 0.5 μm thick formed on the inner surface of the molding hole and a dynamic friction coefficient of the inner surface of the die 1 of 0.15 were used.

[0108] The moldability and durability of the single-cup molding die and double-cup molding die of Comparative Example 3 were evaluated in the same manner as in Example 1 above. As shown in Table 1, the moldability was rated as "X" and the durability was rated as "O".

[0109] <Overall Review> As shown in Table 1, the moldability and durability of the molds of Examples 1 to 7 related to the present invention were favorably evaluated. In particular, the molds of Examples 1 to 3 and 7 using a DLC coating as the easy-slip coating 21 exhibited even more excellent moldability.

[0110] In contrast, the dies of Comparative Examples 1 to 3, which deviate from the gist of the present invention, were evaluated as being inferior in either moldability or durability. [Industrial Applicability]

[0111] The draw-forming die of the present invention can be suitably used when producing a draw-formed product obtained by using a laminate material in which a resin layer is laminated on a metal foil layer as a forming material, such as a packaging material for an electricity storage module. [Explanation of symbols]

[0112] 1: Dice 11: Molding hole 2: Punch 20: Punch body 21: Easy slip coating 22: Easy smooth surface 5: Squeeze molded products 51: Recess 61: Metal foil layer 62, 63: Resin layer L: Laminate material

Claims

1. A die for drawing includes a die having a forming hole that opens to one side thereof, and a punch provided corresponding to the one side of the die, and in a state in which a laminate material having a metal foil layer and a resin layer provided on at least one side thereof is placed on one side of the die, the laminate material is drawn into a concave shape by the punch pressed into the forming hole to form a drawn product, A slippery surface is formed on the tip side surface of the punch that comes into contact with the laminate material, A die for drawing, characterized in that the coefficient of dynamic friction of the slippery surface with respect to the laminate material is set to 0.3 or less, and the Vickers hardness of the slippery surface is set to 200 HV or more.

2. 2. The die for drawing according to claim 1, wherein at least an outer peripheral edge portion of a tip side surface of said punch is formed into said easy-slip surface.

3. 3. The die for drawing according to claim 1 or 2, wherein the punch comprises a punch body and a lubrication coating provided so as to cover the tip surface of the punch body, and the lubrication surface is formed by the surface of the lubrication coating.

4. The die for drawing according to claim 3, wherein the easy-slip coating is made of a diamond-like carbon (DLC) coating.

5. The die for drawing according to claim 3 or 4, wherein the thickness of the easy-slip coating is set to 0.1 μm to 3 μm.

6. The Vickers hardness of the inner peripheral surface of the forming hole of the die is set to 200 HV or more, A die for drawing according to any one of claims 1 to 5, wherein the dynamic friction coefficient of the inner peripheral surface of the forming hole of the die with respect to the laminate material is set to be greater than the dynamic friction coefficient of the easy-slip surface.

7. A method for producing a drawn product, comprising the steps of: drawing a laminate material into a concave shape using a die for drawing according to any one of claims 1 to 6; and producing a drawn product having a concave portion formed therein.

8. A method for producing a packaging material for a storage module, comprising the steps of: using the drawing die according to any one of claims 1 to 6 to draw a laminate material into a concave shape, thereby producing a packaging material for a storage module having a concave portion formed therein.

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