JPS62197202A - Production of extra thin aluminum foil - Google Patents

Abstract

PURPOSE:To satisfactorily produce the titled extra thin foil having a specific thickness and width or below by using work rolls having a specific effective barrel length and a specified diameter or below and subjecting a thin aluminum sheet stock to doubling rolling via a rolling mill lubricant having a specific kinematic viscosity. CONSTITUTION:The effective barrel length L of the upper and lower work rolls 10, 12 is made longer by 20-150mm than the foil width by forming notched parts 16 or shifting the rolls to eliminate the thickness fluctuation or foil breakage by the kiss rolls for extra thin Al foil having <=5mum foil thickness and <=1,000mm width. The diameter of the work rolls 10, 12 is made <=200mm and the curving thereof is minimized by multiple back up rolls. The kinematic viscosity of the hydrocarbon or olefin rolling mill lubricant to be supplied to the work rolls 10, 12 is made 6-15cSt (40 deg.C) to prevent the lateral slipping of the foil. The extra thin Al foil having <=5mum foil thickness of <=1,000mm width is satisfactorily rolled if the thin Al sheet stock is subjected to doubling rolling under the above-mentioned conditions.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a method for manufacturing ultra-thin aluminum foil, and in particular, to continuously manufacture ultra-thin aluminum foil with a thickness of 5 μm or less and a width of 1000 mm or less by rolling. It is about the method.

(Prior Art) Conventionally, when manufacturing aluminum foil, a doubling rolling method in which two aluminum thin sheet materials are overlapped and rolled simultaneously has been suitably employed.

In mass production equipment that employs this doubling rolling method, the upper and lower aluminum thin sheet materials are normally unwound from two uncoilers, and the upper and lower aluminum thin sheet materials are deflated. The aluminum foil is sent to a rolling mill via a group of rolls, and rolled to a predetermined thickness between the rolling rolls (work rolls) of the rolling mill under the overlapping state, and then the obtained aluminum foil is deflated. It is designed to be wound into a coir through a group of fucrols. In addition, in such doubling rolling, usually
The entrance thickness of the upper and lower aluminum thin plate materials is 0.
010 to 0.0201■, the rolling reduction rate is 40 to 55%, the front and rear tensions are set to about 3 to 6KgZ2, the work roll diameter is usually 280 to 3001■φ, and the effective roll barrel length is 1500. ~2000+u.

(Problem) However, the thinnest aluminum foil obtained in normal large-scale mass production equipment as described above is 5 to 6 μm.
Therefore, it was not possible to obtain an extremely thin aluminum foil having a thickness of 5 μm or less. Generally speaking, in foil rolling, the thinner the foil and the wider the width, the more likely shape defects such as flatness will occur, and if a shape defect occurs on the entry side, that part will not be rolled. Therefore, the production of aluminum foil with a thickness of 5 μm or less and a width of more than 1000++ m is not recommended for normal large-scale mass production because it causes problems such as poor shape. This was not possible with the equipment.

In addition, due to the limit imposed by the so-called minimum rollable thickness, it is not possible to roll the aluminum thin sheet material to be rolled to a thickness of 5 μm or less using normal large-scale mass production equipment.Therefore, there is no way to increase the rolling limit. Unless such measures are taken, it is not possible to manufacture such ultra-thin aluminum foil.

(Solution Means) Here, the present invention was made to solve this problem, and its characteristics are as follows: Thickness: 5 μm or less, width: 1000 mm or less In this method, the work roll diameter of the rolling mill is set to 200 mm or less, and the rolling oil supplied to the work roll is 6 to 15 centistokes (40 ° C.), Furthermore, doubling rolling is carried out under conditions where the effective roll barrel length of the work roll is set to be 20 to 150 m++ longer than the width of the resulting ultra-thin aluminum foil. This made it possible to stably produce foil without running out of foil.

As described above, in the present invention, first, in order to deal with the problem of poor shape such as poor flatness, the plate width of the aluminum foil obtained is limited to 1000 mm or less.

Furthermore, even if the sheet width is less than 10,001 I-I, if the effective roll barrel length is, for example, 2,000 mm, a so-called kiss roll will occur at the portion outside the sheet width: approximately 500 mm, and the pressure acting on this kiss roll portion will increase. In order to eliminate problems such as shape defects caused by the work roll being bent into an undesirable shape due to the influence of was set to be 20 to 150 m longer than the width of the resulting ultra-thin aluminum foil.

Under such conditions, the rolling part of the thin sheet material is generally carried out at the central part of the work rolls, so in the present invention, it is preferable to roll the thin sheet material at the contact part (rolling part) of the pair of upper and lower work rolls. Both ends of the aluminum foil are constructed so that they protrude within a range of 10 to 75 mm from both ends of the ultra-thin aluminum foil formed by rolling a thin plate material. In the case of overhang, the kiss roll load between the work rolls becomes excessive, making it difficult to roll with low horsepower.
In addition, if the protrusion amount is less than 10 m, rolling may become impossible due to the ultra-thin aluminum foil slipping. It is necessary to determine the dimensions of the work roll so that it is 20 to 150 mm longer. By the way, the length of the rolled part is the barrel length)
When rolling a foil with a width of 1000 m using a work roll with a width of 2000 m, it is recognized that the kiss roll load is about half of the total rolling load.

In addition, the dimensions of the rolled part in the axial direction of the work roll,
In other words, if the barrel length is too long, the effective roll barrel length (L) is determined by extending the outer periphery 16 at both ends of each barrel 14 of the upper and lower work rolls 10.12, as shown in FIG. , can be obtained by cutting and removing over a predetermined length. In this case, the portion indicated by the reference numeral 18 becomes a substantial rolled portion (barrel).

In addition, when the barrel length is too long, the work roll shift shown in FIG. 3 is adopted, in which a structure is adopted for the shift 1 in which at least one of a pair of work rolls as shown in FIG. There is no problem in using a mill. This work roll shift mill was originally developed to reduce edge drop by letting the work roll curve at the edge of the plate taper, but this has been developed to be advantageous for implementing the present invention. It can be used for. In addition, in the figure, 2o and 22 are upper and lower reinforcing rolls.

Furthermore, in the present invention, in order to deal with the limit of the minimum thickness that can be rolled, which has been a problem in the past, the roll diameter of the work rolls (10, 12>) is set to 200 ψ or less, In particular, by setting the work roll diameter to 100 mm or less, it is possible to advantageously produce ultra-thin aluminum foil with a thickness of about 4 μm or less. When there is a risk of horizontal roll deflection, the conventionally proposed Sendzmir
imir) mill, Z-lligh mill,
It is desirable to use a Y-mill, a 6-stage cluster mill, a 12-stage roll mill, or the like.

Furthermore, in the present invention, as the rolling oil supplied to the work rolls of the rolling mill, one having a kinematic viscosity of 6 to 15 centistokes (cSt: 40°C) is used. By the way, such rolling oil is intended to reduce the coefficient of friction between the work roll and aluminum foil, etc., but if the kinematic viscosity of this rolling oil at 40"C is less than 6 cSt, As the amount of rolling oil pressed into the roll becomes small, the coefficient of friction becomes excessive, making it difficult to manufacture ultra-thin foil of 5 μm or less.Furthermore, when the kinematic viscosity exceeds 15 cSt, the difference between the roll gap and the If the amount of oil is too large, the coefficient of friction becomes too small, and the material being rolled may skid, resulting in poor rolling, or winding becomes difficult, leading to foil breakage. The kinematic viscosity of the supplied rolling oil must be within the range of 6 to 15 cSt at 40"C.

Incidentally, in conventional rolling mills, generally 2
Since aluminum foil with a low kinematic viscosity of less than cSt (40°C) was used, the coefficient of friction between the work roll and the rolled material was large, and therefore it was extremely difficult to manufacture extremely thin aluminum foil with a thickness of approximately 5 μm or less. It was difficult.

In addition, as the rolling oil having a kinematic viscosity of 6 to 15 cSt (40°C), hydrocarbon-based or olefin-based rolling oils are preferably used. It has been confirmed through experiments that the rolling limit can be improved by increasing the viscosity of the rolling oil as well as by reducing the diameter of the rolling oil.

In the present invention, by performing a normal doubling rolling operation under the above-mentioned work roll diameter, rolling oil viscosity, and effective roll barrel length, a roll having a thickness of 5 μm or less and a width of 1000 inches or less is produced. This made it possible to advantageously produce ultra-thin aluminum foil continuously.

(Effects of the Invention) According to the present invention, the rolling limit can be effectively improved while eliminating harmful kiss roll portions, and the rolling limit can be effectively improved without causing problems with shape defects such as poor flatness. In particular, it has become possible to stably manufacture ultra-thin aluminum foil with a thickness of 4 μm or less without causing the foil to break.

(Example) An example will be described below in order to clarify the present invention more specifically, but the present invention is not limited in any way by the description of such an example. Needless to say, it should be understood that the examples illustrated here are only a part of the many experiments conducted by the inventor.

First, roll diameter x effective barrel length (L) - 50 TsuruφX 7
An aluminum material made of pure aluminum (0,3511
A normal rolling (single) operation was performed using a 5-pass schedule from A thickness x 50 fin width) to obtain an aluminum thin plate material with a thickness of 6 μm. Furthermore, by overlapping and doubling rolling two sheets of the obtained thin plate material with a thickness of 6 μm, the thickness is about 3.5 μm and the width is about 50 μm.
It was possible to stably and continuously obtain ultrathin aluminum foil for the fin without causing problems such as foil breakage. In addition,
In any rolling operation, the rolling oil should be kept at 40°C.
A material having a kinematic viscosity of 10 cSt was used and supplied to the work roll.

Further, when similar doubling rolling was performed using the work roll diameter of 155 mm, it was possible to continuously produce ultra-thin aluminum foil having a thickness of 5 μm.

In contrast, the effective barrel length of the work roll is 250 m.
In the case of using m, rolling became impossible due to foil breakage due to poor flatness, and an ultra-thin aluminum foil could not be obtained. Furthermore, when the viscosity of the rolling oil supplied to the work rolls is 3.5 cSt,
The product thickness of the resulting aluminum foil was 5.5 μm, making it impossible to obtain an aluminum foil with a thickness of 5 μm or less.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating an example of processing for making the rolled portion into a size suitable for carrying out the present invention when the barrel length of the work roll is long. FIG. 2 is a diagram showing a work roll shift arrangement for making the rolling part suitable for carrying out the present invention when the barrel length of the work roll is long, and FIG. 3 is a diagram showing such a work roll shift arrangement. 1 is a schematic diagram of a work roll shift l-mill equipped with a mechanism. 10: Upper work roll 12: Lower work roll 14:
Barrel 16: Cut section 18: Rolled section
20: Upper reinforcing roll 22: Lower reinforcing roll

Claims (1)

[Claims] A method of continuously rolling an ultra-thin aluminum foil with a thickness of 5 μm or less and a width of 1000 mm or less, so that the work roll diameter of the rolling mill is 200 mm or less, and as rolling oil to be supplied to the work rolls. 6 to 15 centistokes (40 °C) was used, and the effective roll barrel length of the work roll was set to be 20 to 150 mm longer than the width of the resulting ultra-thin aluminum foil, and doubling rolling was carried out. A method for producing ultra-thin aluminum foil.