JPH08158027A - Annealing method for rolled copper foil - Google Patents

Abstract

PURPOSE: To prevent the occurrence of adhesion between rolled copper foils at the time of annealing the rolled copper foils in a piled state. CONSTITUTION: At the time of annealing rolled copper foils in a piled state, the adhesion between the rolled copper foils can be prevented by inserting an electrolytic copper foil between the rolled copper foils and performing annealing in this state. Further, the adhesion between the rolled copper foils can be prevented by inserting a roughed copper foil of 0. 5-1.5μm surface roughness (Ra) of both surfaces between the rolled copper foils and performing annealing in this state. The roughed copper foil can be obtained by applying roughing treatment method, such as sand blasting, brushing, chemical etching, electrolytic etching, electrodeposition roughing, and embossing, to both surfaces of a rolled copper foil prepared by rolling or an electrolytic copper foil prepared by electrolytic method. Moreover, the piling of the rolled copper foils is generally performed by coiling the rolled copper foil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of annealing rolled copper foils by superposing them on each other, while preventing the polymerized rolled copper foils from adhering to each other.

[0002]

2. Description of the Related Art Conventionally, rolled copper foil has been used as a shield material for electric wires and the like. The rolled copper foil is obtained by melting and casting copper or a copper alloy, followed by hot rolling, then repeating cold rolling and intermediate annealing to obtain a copper thin plate of 0.1 to 1.0 mm, and then performing intermediate annealing. After that, cold rolling is performed to finally manufacture the film having a thickness of 35 μm or less. Then, in order to remove the rolling oil or the like adhering to the surface of the rolled copper foil, degreasing / cleaning treatment is performed with an organic solvent such as trichlene or normal paraffin. When such a rolled copper foil is used as a shield material for electric wires or the like, it is necessary to bring the rolled copper foil into close contact with the electric wires or the like, and it is generally softened. To soften the rolled copper foil, it is necessary to perform final annealing at a temperature equal to or higher than the recrystallization completion temperature (generally 250 ° C. or higher).

Conventionally, this final annealing is carried out by winding the obtained rolled copper foil into a coil and holding this coil at a temperature of 250 ° C. or higher for 2 to 5 hours or more. However, when the rolled copper foil is wound into a coil, the rolled copper foils are polymerized and are in contact with each other, so that the rolled copper foils may be bonded to each other by the final annealing. In particular,
The adhesion between the rolled copper foils was remarkable at the beginning of coil winding. It is considered that this is because the rolled copper foil is softened by the final annealing, and a high pressure is applied to the rolled copper foil toward the center of the coil.

When the rolled copper foils are bonded to each other in this manner, they are difficult to peel off on one rolled copper foil, and several rolled copper foils are in an integrated state, resulting in a decrease in productivity of the softened rolled copper foil. It was Further, even if the rolled copper foils are separated from each other, defects such as wrinkles occur on the surface of the rolled copper foils, and the productivity of the rolled copper foils is reduced. Further, in the worst case, there is a drawback that the rolled copper foil cannot be unwound (rewound) at all.

[0005]

DISCLOSURE OF THE INVENTION The present inventor has investigated why the rolled copper foils polymerized by the final annealing adhere to each other. That is, it was examined whether or not the rolled copper foils were adhered as if they were fused even though the final annealing was performed at a temperature much lower than the melting point of copper.
As a result, the rolled copper foil was thought to be because the surface thereof was in a mirror state because it was repeatedly cold-rolled. That is, when rolled copper foils having a mirror surface are polymerized and brought into contact with each other, the distance between the respective copper elements forming each copper foil becomes very close, and the electrons in each copper foil cross each other beyond the polymerized surface. It is thought that it is for communicating with each other. In particular, since the rolled copper foil surface is a mirror surface, this phenomenon occurs on the entire rolled copper foil, and in an extreme case, it is considered that the rolled copper foils adhere to each other as if they were fused. Of.

Therefore, in the present invention, a certain inclusion is provided between the polymerized rolled copper foils, and the distances between the copper elements constituting each rolled copper foil are not close to each other over the entire surface. By carrying out annealing in this way, it is intended to prevent the rolled copper foils from adhering to each other.

[0007]

Means for Solving the Problems That is, the present invention is a method of polymerizing and annealing a rolled copper foil, wherein between the rolled copper foils,
The present invention relates to a method for annealing a rolled copper foil, which is characterized in that an electrolytic copper foil is inserted. Further, in the method of polymerizing rolled copper foils and annealing, the surface roughness (R
a) is a method of annealing a rolled copper foil, characterized in that a roughened copper foil having a thickness of 0.5 to 1.5 μm is inserted.

The rolled copper foil used in the present invention is obtained by a conventionally known method. That is, after melting and casting copper or a copper alloy, hot rolling is performed, and then cold rolling and intermediate annealing are repeated to obtain a copper thin plate of 0.1 to 1.0 mm. Then, intermediate annealing and cold rolling are further performed to finally use the rolled copper foil adjusted to have a thickness of, for example, 35 μm or less. Therefore, the rolled copper foil referred to in the present invention includes rolled copper alloy foil. Copper alloys containing phosphorus (P), tin (Sn)
Containing phosphorus, or phosphorus (P) and tin (S
Those containing n) are generally used, and those containing other elements may be used. Phosphorus (P) is generally contained in an amount of 1% by weight or less, and particularly 0.1% by weight.
It is preferable that the content is not more than wt%. Tin (Sn)
Is generally contained in an amount of 10% by weight or less, particularly preferably 6% by weight or less, and most preferably 0.2% by weight or less. Specifically, JI
SH 3100, JIS H3110, JIS H
The copper alloy specified in 3130 and other various commercialized copper alloys are used.

Since rolling oil or the like is attached to the surface of the rolled copper foil, the rolling oil or the like is removed by performing degreasing / washing treatment with an organic solvent such as trichlene or normal paraffin. This degreasing / cleaning treatment may be performed before the annealing described below or after the annealing described below.

Next, the rolled copper foil is polymerized. Polymerization of rolled copper foil generally means winding the rolled copper foil into a coil. That is, when rolling the rolled copper foil,
The upper layer rolled copper foil is polymerized with the lower layer rolled copper foil.
It should be noted that what has been described above is general, and the term "polymerization of a rolled copper foil" in the present invention also encompasses stacking a plurality of flat rolled copper foils as they are without winding them.

What is important in the present invention is that when the rolled copper foil is polymerized, an electrolytic copper foil is inserted between the rolled copper foils in contact with each other. The electrolytic copper foil referred to in the present invention is a copper foil obtained by a conventionally known electrolytic method, and copper is deposited by electrodeposition on a rotating drum immersed in an electrolytic solution in which copper is dissolved. It is a copper foil obtained by doing so. Therefore, the surface of this electro-deposited copper foil is composed of a surface that is in contact with the rotating drum and a surface that is not in contact with the rotating drum. In the electrolytic copper foil, the former surface is relatively smooth and is called a shiny surface, and the latter surface is relatively rough and is called a matte surface.
However, even the shiny surface, which is said to be relatively smooth, is rougher than the surface of the rolled copper foil. In this way, the electrolytic copper foil having a relatively rough surface is inserted between the rolled copper foils, so that the copper elements forming each rolled copper foil are prevented from coming close to each other over the entire surface. You can do it. As the material to be inserted between the rolled copper foils, the electrolytic copper foil made of copper is adopted because the surface of the rolled copper foil is embossed so that the rolled copper foil has the same hardness and the like. Alternatively, it is for preventing the surface of the electrolytic copper foil from being deformed.

The thickness of the electrolytic copper foil used in the present invention may be any thickness, but it is generally preferable to use a thickness of about 10 to 30 μm, particularly about 18 μm. The most preferable one is The electrolytic copper foil becomes expensive as it becomes thinner, so that it is uneconomical to use an electrolytic copper foil having a thickness of less than 10 μm. On the other hand, when the thickness of the electrolytic copper foil exceeds 30 μm,
If this is inserted into a coil, the weight of the coil becomes heavy, or the outer diameter of the coil becomes too large, which tends to be difficult to handle.

In the present invention, when the rolled copper foil is polymerized, a roughened copper foil having a surface roughness (Ra) of 0.5 to 1.5 μm is inserted between the rolled copper foils in contact with each other. Is also good.
Such a roughened copper foil may be a roughened copper foil by treating both surfaces of a general rolled copper foil, or may be a roughened copper foil that is untreated or treated on both surfaces of an electrolytic copper foil. good. When the surface roughness (Ra) is less than 0.5 μm, the surface approaches a mirror surface, and adhesion may occur between the roughened copper foil and the rolled copper foil, which is not preferable. On the other hand, surface roughness (Ra)
Is more than 1.5 μm, the effect of preventing adhesion between rolled copper foils tends not to be further improved. Therefore, it is uneconomical to perform the roughening treatment so that the surface roughness (Ra) exceeds 1.5 μm. The surface roughness (Ra) in the present invention uses Surfcom 303B manufactured by Tokyo Seimitsu Co., Ltd.
The measurement was performed under the conditions of a stylus radius of 2 μm, a stylus drive speed of 0.3 mm / sec, and a cutoff value of 0.8 mm.

The roughened copper foil can be obtained by roughening both surfaces of a rolled copper foil or the like. As a roughening treatment method, a sandblasting method, a brush grinding method, a chemical etching method, an electrolytic etching method, an electrodeposition roughening method, an embossing method can be applied alone or in combination. The sandblast method is to spray sand particles onto the surface of a rolled copper foil or the like to roughen the surface. The brush grinding method is to roughen the surface of a rolled copper foil or the like by rubbing it with a brush. Further, the chemical etching method is a method in which a very small amount of the surface of a rolled copper foil or the like is dissolved by a chemical method to form irregularities on the surface to roughen the surface. In the electrolytic etching method, a very small amount of the surface of a rolled copper foil or the like is dissolved in an electrolytic solution to form irregularities on the surface and roughen the surface. The electrodeposition roughening method is to deposit copper on the surface of a rolled copper foil or the like by the electrodeposition method, and to impart the irregularities originally possessed by the deposited copper to the surface of the rolled copper foil or the like. In the embossing method, a pressure roll having irregularities formed on the surface is pressed against the surface of a rolled copper foil or the like, and the irregularities are transferred to the surface of the rolled copper foil or the like. As the concavo-convex pattern formed on the surface of the pressure roll, any pattern such as a silk lattice pattern, a satin pattern, and a grain pattern is adopted. In addition, methods other than these roughening treatment methods,
It can be used in the present invention.

When the rolled copper foil to be annealed is polymerized, the electrolytic copper foil or the roughened copper foil as described above is inserted between the rolled copper foils. Then, the rolled copper foil is annealed at a temperature equal to or higher than the recrystallization completion temperature to soften the rolled copper foil. The annealing temperature is
Generally, it is 250 ° C or higher. The holding time of annealing is 1 hour or more, preferably about 2 hours.
The temperature and time of these annealings can be appropriately determined in consideration of the elemental composition of the rolled copper foil and the thickness of the rolled copper foil, and the conditions for softening the rolled copper foil to a satisfactory degree. After the rolled copper foil is annealed and softened, if rolling oil etc. adheres to the surface of the rolled copper foil, degreasing and cleaning treatment with an organic solvent such as trichlene, normal paraffin, etc. Is preferably removed.

[0016]

Example [Adjustment of rolled copper foils a to c] After melting and casting a copper alloy,
Hot rolling was performed, and then cold rolling and intermediate annealing were repeated several times to obtain a rolled copper foil having a thickness of 9 μm and a width of 600 mm.
Then, both surfaces were degreased and washed with an organic solvent. Here, the following three types were used as the copper alloy. That is, (a) phosphorus (P) 0.02 wt% and the balance copper (Cu)
Copper alloy (corresponding to JIS C 1220), (b) tin (Sn) 0.2 wt% and the balance copper (Cu) (generally used Cu-Sn alloy), (c ) A copper alloy containing 6% by weight of tin (Sn) and 0.1% by weight of phosphorus (P) and the balance of copper (Cu) (corresponding to JISC 1591) was used. Then, the rolled copper foil obtained by using the copper alloy of (a) is referred to as a rolled copper foil a, the rolled copper foil obtained by using the copper alloy of (b) is referred to as a rolled copper foil b, and (c The rolled copper foil obtained by using the copper alloy of 1) was designated as rolled copper foil c.

Example 1 In a state where an electrolytic copper foil having a thickness of 18 μm prepared in advance is superposed on a rolled copper foil a, a rolled steel foil a of a steel pipe having an outer diameter of 81 mmφ is tensioned so as not to cause wrinkles and winding deviation. The coil was wound up until the weight reached 50 kg. Then, this coil was held at 320 ° C. for 2 hours for annealing. In addition, in order to raise the temperature of the coil to 320 ° C., about 7 to
It took 9 hours. Further, it took about 15 to 17 hours to cool the coil to room temperature after annealing. After annealing and cooling as described above, a rewinding operation was performed while separating the electrolytic copper foil and the rolled copper foil a by a separator, and the electrolytic copper foil and the rolled copper foil a were well separated. However, the rewinding work could be performed without causing surface defects such as wrinkles.

Example 2 Instead of the rolled copper foil a, a rolled copper foil b was used and the annealing temperature was 340 ° C. Annealing was carried out in the same manner as in Example 1, and the rewinding work was carried out in the same manner. went. As a result, as in the case of Example 1, the rewinding work could be successfully performed.

Example 3 Instead of the rolled copper foil a, a rolled copper foil c was used and the annealing temperature was set to 370 ° C. Annealing was performed in the same manner as in Example 1, and the rewinding work was performed in the same manner. went. As a result, as in the case of Example 1, the rewinding work could be successfully performed.

Example 4 On both sides of a 18 μm thick tough pitch copper foil (rolled copper foil),
By applying the sandblast method, the surface roughness (Ra) is 0.
A 6 μm roughened copper foil was obtained. With the roughened copper foil superposed on the rolled copper foil a, the rolled copper foil a weighs 50 kg under tension such that wrinkles and winding deviation do not occur in a steel pipe with an outer diameter of 81 mmφ.
It wound up until it became, and the coil was created. After that,
Annealing was performed in the same manner as in Example 1, and rewinding work was performed in the same manner. As a result, as in the case of Example 1, the rewinding work could be successfully performed.

Example 5 Instead of the rolled copper foil a, a rolled copper foil b was used and the annealing temperature was 340 ° C. Annealing was carried out in the same manner as in Example 4, and the rewinding work was carried out in the same manner. went. As a result, as in the case of Example 4, the rewinding work could be favorably performed.

Example 6 Instead of the rolled copper foil a, a rolled copper foil c was used and the annealing temperature was set to 370 ° C. Annealing was performed in the same manner as in Example 4, and the rewinding work was performed in the same manner. went. As a result, as in the case of Example 4, the rewinding work could be favorably performed.

Example 7 Instead of using a roughened copper foil having a surface roughness (Ra) of 0.6 μm, a roughened copper foil having a surface roughness (Ra) of 1.5 μm was used. Annealing was performed in the same manner as in Example 4, and rewinding work was performed in the same manner. As a result, as in the case of Example 4, the rewinding work could be favorably performed.

Example 8 Instead of the rolled copper foil a, a rolled copper foil b was used and the annealing temperature was 340 ° C. Annealing was carried out in the same manner as in Example 7, and rewinding work was carried out in the same manner. went. As a result, as in the case of Example 7, the rewinding work could be favorably performed.

Example 9 Instead of the rolled copper foil a, a rolled copper foil c was used and the annealing temperature was set to 370 ° C. Annealing was performed in the same manner as in Example 7, and the rewinding work was performed in the same manner. went. As a result, as in the case of Example 7, the rewinding work could be favorably performed.

Example 10 Instead of the roughened copper foil used in Example 4, the elemental composition of the roughened copper foil was 0.02% by weight of phosphorus (P) with the balance being copper (Cu), and the surface roughness. Annealing was performed in the same manner as in Example 4 except that (Ra) was set to 1.0 μm, and rewinding work was performed in the same manner. As a result, as in the case of Example 4, the rewinding work could be favorably performed.

Example 11 Instead of the roughened copper foil used in Example 5, the elemental composition of the roughened copper foil was 0.2% by weight of tin (Sn) with the balance being copper (Cu) and the surface roughness. Annealing was performed in the same manner as in Example 5 except that (Ra) was set to 1.0 μm, and rewinding work was performed in the same manner. As a result, as in the case of Example 5, the rewinding work could be satisfactorily performed.

Example 12 Instead of the roughened copper foil used in Example 6, the elemental composition of the roughened copper foil was 6% by weight of tin (Sn) and 0.1% by weight of phosphorus (P) with the balance being copper ( Cu), and the surface roughness (Ra) was 1.0 μm, annealing was performed in the same manner as in Example 6, and rewinding work was performed in the same manner. As a result, as in the case of Example 6, the rewinding work could be satisfactorily performed.

Example 13 Instead of producing the roughened copper foil by applying the sand blast method which is the method used in Example 10, an embossing method (embossed pattern is a silk lattice pattern) is applied and roughened. Annealing was performed in the same manner as in Example 10 except that the copper foil was prepared, and rewinding work was performed in the same manner. As a result, as in the case of Example 10, the rewinding work could be favorably performed.

Example 14 Instead of producing a roughened copper foil by applying the sand blasting method which is the method used in Example 11, an embossing method (embossed pattern is a silk lattice pattern) is applied and roughened. Annealing was performed in the same manner as in Example 11 except that the copper foil was prepared, and rewinding work was performed in the same manner. As a result, as in the case of Example 11, the rewinding work could be satisfactorily performed.

Example 15 Instead of producing the roughened copper foil by applying the sand blast method which is the method used in Example 12, an embossing method (embossed pattern is a silk lattice pattern) is applied and roughened. Annealing was performed in the same manner as in Example 12 except that the copper foil was prepared, and rewinding work was performed in the same manner. As a result, as in the case of Example 12, the rewinding work could be favorably performed.

Comparative Example 1 Annealing was performed in the same manner as in Example 1 except that the electrolytic copper foil was not used. However, it took about 5 hours to raise the temperature of the coil to 320 ° C. Also, it took about 10 hours to cool the coil to room temperature after annealing. Then, when the rewinding operation was performed in the same manner as in Example 1, the rolled copper foils a were adhered to each other and were not easily peeled off, and the rewinding operation could not be smoothly performed. Further, even if the rewinding work can be performed, when the rolled copper foil a is peeled off,
Many wrinkles were formed on the surface of the rolled copper foil a, and it was not possible to obtain a usable rolled copper foil a.

Comparative Example 2 Annealing was performed in the same manner as in Example 2 except that the electrolytic copper foil was not used. At this time, the temperature rising time and the cooling time were the same as those in Comparative Example 1.
It was similar to the case of. Then, when the rewinding operation was performed in the same manner as in Example 1, the rolled copper foils b were adhered to each other and were not easily peeled off, and the rewinding operation could not be smoothly performed. Further, even if the rewinding work can be performed, when the rolled copper foils b are separated from each other, many wrinkles are formed on the surface of the rolled copper foil b,
It was not possible to obtain usable rolled copper foil b.

Comparative Example 3 Annealing was performed in the same manner as in Example 3 except that the electrolytic copper foil was not used. At this time, the temperature rising time and the cooling time were the same as those in Comparative Example 1.
It was similar to the case of. Then, when a rewinding operation was performed in the same manner as in Example 1, the rolled copper foils c were adhered to each other and were not easily peeled off, and the rewinding operation could not be smoothly performed. Even if the rewinding work can be performed, when the rolled copper foils c are peeled off, many wrinkles are formed on the surface of the rolled copper foil c,
It was not possible to obtain a usable rolled copper foil c.

As is clear from a comparison of Examples 1 to 15 and Comparative Examples 1 to 3 above, when electrolytic copper foil or roughened copper foil is inserted between polymerized rolled copper foils and annealed, rolled copper foils are obtained. It can be seen that the adhesion is unlikely to occur between them, the rewinding work can be favorably performed, and that the rolled copper foil rewound is less likely to have surface defects such as wrinkles. On the other hand, when annealing is performed without inserting an electrolytic copper foil or a roughened copper foil between the polymerized rolled copper foils, the rolled copper foils are bonded to each other, which makes it difficult to perform rewinding work or rewinding. It can be seen that surface defects such as wrinkles easily occur on the rolled copper foil.

[0036]

In the annealing method according to the present invention, the surface roughness (Ra) of the electrolytic copper foil or both surfaces is 0.5 to 0.5 between the polymerized rolled copper foils.
A roughened copper foil having a thickness of 1.5 μm is inserted and annealed. Therefore, since it is possible to prevent the mirror surfaces of the rolled copper foil from coming into contact with each other, the distance between the respective copper elements forming the respective mirror surfaces does not approach, and the electrification in each copper foil exceeds the polymerization surface and is mutually different. It is possible to prevent them from communicating with each other in the rolled copper foil. The copper element forming the convex portion of the electrolytic copper foil or the roughened copper foil and the copper element forming the mirror surface of the rolled copper foil are close to each other, but it is the electrolytic copper foil or the roughened copper foil. Only the portion corresponding to the convex portion of the foil does not work on the entire surface of the rolled copper foil. Therefore, the rolled copper foil and the electrolytic copper foil or roughened copper foil, the electrons in each copper foil do not pass through the entire surface, only the electrons in each copper foil partially pass through, It is easily peeled off, and defects such as wrinkles are less likely to occur during peeling.

[0037]

As is apparent from the above description, by adopting the method according to the present invention, it is possible to prevent electrons in each copper foil from passing through each other between the rolled copper foils, and to polymerize the rolled copper foils. Even if it is annealed, the rolled copper foils can be prevented from adhering to each other. Further, between the rolled copper foil and the electrolytic copper foil or roughened copper foil, the electrons in each copper foil do not pass through the entire surface, and the rolled copper foil and the electrolytic copper foil can be easily peeled off. It is possible to prevent the occurrence of surface defects such as wrinkles when peeling. Therefore, the yield when the rolled copper foil is annealed is improved, and the productivity is increased.

Further, since the material inserted between the rolled copper foils is the same copper as the rolled copper foils, the hardness and the physical properties are similar to each other, so that the rolled copper foils may be adversely affected. And the rolled copper foil can be annealed without deteriorating the performance. Further, since the rolled copper foil and the electrolytic copper foil to be inserted are similar in hardness, the surface of the electrolytic copper foil is less likely to be deformed by the rolled copper foil, and the electrolytic copper foil etc. that has been used once Even if there is, it also has an effect that it can be used again by inserting it between the rolled copper foils.

Claims (4)

[Claims] 1. A method for annealing rolled copper foils, characterized in that a rolled copper foil is polymerized and annealed, and an electrolytic copper foil is inserted between the rolled copper foils. 2. A method of polymerizing rolled copper foils and annealing the rolled copper foils, wherein the surface roughness (Ra) of both surfaces is 0.5 between the rolled copper foils.
A method for annealing a rolled copper foil, characterized in that a roughened copper foil having a thickness of up to 1.5 μm is inserted. 3. The method for annealing a rolled copper foil according to claim 1, wherein the rolled copper foil is wound into a coil and polymerized. 4. A copper foil is obtained by subjecting a copper foil to a roughening treatment method selected from the group consisting of a sandblasting method, a brush grinding method, a chemical etching method, an electrolytic etching method, an electrodeposition roughening method and an embossing method. A roughened copper foil is used.
A method for annealing a rolled copper foil as described.