JP2002087690A - Method of manufacturing film roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a film roll capable of obtaining the film roll of a final product having good winding shape with no winding bumps and no winding wrinkles. SOLUTION: This method of manufacturing the film roll is utilized to manufacture the product roll by slitting the film in plural specified product widths while the film is unwound from an intermediate roll formed by winding the film manufactured in a film manufacturing process, and in this method, the winding diameter distribution of the intermediate film rolls is measured, an oscillating condition in which the deviation of the winding diameter distribution is averaged is found from measured values of the winding diameter distribution, and while the intermediate film roll is moved in the shaft direction in the oscillating condition, the intermediate film roll is slit to manufacture the product film roll.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method of manufacturing a film roll for manufacturing a final product roll slit into a predetermined width from an intermediate roll of a wide intermediate product formed in a film forming process. The present invention relates to a method of manufacturing a film roll capable of obtaining a product roll having a small winding diameter difference in the width direction, that is, a winding shape having a good winding diameter distribution.

[0002]

2. Description of the Related Art A film made of a thermoplastic resin such as polyester, polyamide, or polypropylene has a predetermined width according to use when sold as a base film for various functional films such as a magnetic recording medium and a heat ray reflective film. It is shipped as a final product in the form of rolls of a predetermined length.
In this product roll, there is a strict requirement from the step of forming the functional film on the unevenness of the winding thickness in the width direction, that is, the distribution of the winding diameter.

Therefore, first, in a film forming process, the thickness in the width direction of the film is controlled to a predetermined profile, for example, a uniform thickness over the entire width. The thickness of the film is adjusted by a group of thickness adjusting means arranged over the entire width of a wide die for extruding the molten polymer. The thickness adjusting means group is configured to include a heater group for controlling a wide die temperature, and a gap adjusting tool group for adjusting a discharge gap of the molten polymer. Also, these heaters,
Adjustment devices, such as a gap adjuster, are arranged for every fixed section over the full width of a wide die, and adjust the thickness of the section.

[0004] The thickness of the film is adjusted based on the measured values of the thickness of the product film (normally, the film after biaxial stretching) measured at each downstream measurement point in the width direction. Generally, a multi-point thickness control means for controlling the thickness adjusting means groups, adjusting the respective polymer discharge amounts over the entire width of the wide die, and controlling to a desired film thickness. Such a multipoint thickness control method is known as proposed in, for example, Japanese Patent Application Laid-Open No. 7-108586.

[0005] As described above, the method of controlling the film thickness profile by the multipoint thickness control means is to control the thickness of a biaxially stretched film produced by biaxially stretching a wide polymer discharged from a die. Is generally measured and controlled to provide a target thickness profile.

[0006]

However, even if the thickness of the biaxially stretched film of the product is controlled within a control value in the above-mentioned film forming process, the biaxially stretched film is laminated in a roll shape. In the formed intermediate roll, when laminated, the unevenness of the film thickness is accumulated, and the distribution of the winding diameter may be deteriorated. In other words, when the accumulation of such thick and thin spots occurs, there arises a problem that, at a specific position in the width direction of the intermediate roll, bumps and wrinkles that cannot be controlled by the above-described multipoint thickness control means occur.

[0007] If the bumps and the like occur in a product roll manufactured by slitting the intermediate roll to a predetermined width while keeping the intermediate roll, there is a problem that the winding diameter distribution is poor and the product becomes defective. If the slit width is designed so that the product does not enter the product roll, there is a problem that the product yield is reduced.

[0008] The hump in the above-mentioned product roll,
Defective winding shapes such as wrinkles, for example, when used as a support in the manufacture of a magnetic recording medium at the customer, coating irregularities when applying the magnetic layer or errors during magnetic recording or reproduction,
Alternatively, when slitting into a magnetic tape of a predetermined width after applying the magnetic layer, there is a problem that there is a difference in a longitudinal direction between the respective magnetic tapes and it is not possible to wind up neatly,
In other words, the requirements for the winding diameter distribution are severe. This problem is particularly remarkable in a base film for a magnetic recording medium or the like, which is increasingly thinned due to a demand for long-time recording and high-density recording.

The present invention has been made in view of the above circumstances, and has as its object to provide a method of manufacturing a film roll capable of obtaining a film roll of a final product having a good winding appearance without bumps and wrinkles. It is.

[0010]

The above-mentioned object is achieved by the present invention described below. That is, the present invention relates to a film roll manufacturing method for manufacturing a product roll by slitting a plurality of predetermined product widths while rewinding the film from an intermediate roll formed by winding up a film manufactured in a film forming process. The winding diameter distribution in the width direction of the intermediate roll is measured, and the deviation of the winding diameter distribution in each product roll after slit is obtained from the measured value of the winding diameter distribution, and the deviation of the product roll having the largest deviation is averaged. A method of manufacturing a film roll, characterized in that a product roll is manufactured by slitting while moving the intermediate roll in the axial direction as described above.

As described above, in the present invention, the deviation distribution of the winding diameter of the important quality is predicted for each of the product rolls from the previously measured winding diameter distribution of the intermediate roll, and the deviation of the product roll having the largest deviation is averaged. The roll diameter distribution of problematic product rolls is improved and defective products are reduced, and the roll diameter distribution of other product rolls is also averaged to improve quality and overall production. It also has the effect of improving the performance and achieves the object.

In the above-mentioned present invention, when the both ends of the intermediate roll are cut off rolls without forming products, and the product roll is manufactured from the intermediate portion, the product roll having the largest deviation is adjacent to the cut off roll. In many cases, it is one of the product rolls, so the deviation is determined for the product roll adjacent to the cut-off roll, and the processing is simplified by averaging the deviation of the product roll with the larger deviation. The configuration of the oscillation amount indicating device and the like can be simplified.

Further, the winding diameter distribution of the intermediate roll is measured at predetermined time intervals even during the formation thereof, and a product roll having the maximum deviation is determined for each winding diameter distribution measured at the predetermined time interval. With the configuration in which the product roll to be averaged every predetermined time is switched to the product roll having the largest deviation, averaging of the winding diameter distribution becomes more effective.

Furthermore, the present invention achieves the same object,
In addition to the above-described deviation equalizing method, the following method is included. One of them is a Fourier analysis method having the following configuration. That is, in a film roll manufacturing method of manufacturing a product roll by slitting a plurality of predetermined product widths while rewinding the film from an intermediate roll formed by winding up the film manufactured in the film forming process, Measure the winding diameter distribution in the width direction, determine the peak frequency by Fourier analysis of the deviation distribution from the average value, if there is a plurality of the peak frequency or the peak frequency, the frequency of the weighted average by the intensity ratio or these A method of manufacturing a film roll, characterized in that a product roll is manufactured by slitting while oscillating an intermediate roll in an axial direction with an integral multiple of the amplitude as an amplitude. According to this method, sufficient averaging of the outer diameter can be achieved.

The other is a simulation method having the following configuration. That is, in a film roll manufacturing method of manufacturing a product roll by slitting a plurality of predetermined product widths while rewinding the film from an intermediate roll formed by winding up the film manufactured in the film forming process, The winding diameter distribution and the number of laminated films are measured, and the virtual thickness profile of the film forming the intermediate roll is obtained from the winding diameter distribution and the number of laminated films. Simulate with a roll production model that oscillates under the conditions and winds up the number of laminations, finds the outer diameter distribution of the product roll formed by changing the oscillating conditions in the roll production model, and at least the outer diameter distribution satisfies the product specifications Roll manufacturing method of manufacturing a product roll by oscillating under the oscillating condition in case A. By this method, the outer diameter distribution can be optimized.

Incidentally, the virtual thickness profile in this simulation method can be obtained by various methods. That is, a method using a sine wave or a composite wave of the peak frequency obtained by Fourier analysis of the deviation distribution from the average value of the measured winding diameter distribution of the effective intermediate roll when periodicity is recognized in the outer diameter distribution, Alternatively, there is a method using a thickness profile obtained by dividing the winding thickness distribution obtained from the winding diameter distribution of the intermediate roll, which can be widely applied, by the number of laminations.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings based on examples and other embodiments. Here, FIG. 1 is an explanatory diagram of a film manufacturing process according to the present invention, and FIG. 2 is an explanatory diagram of a slit device used in FIG.

In FIG. 1, reference numeral 1 denotes a die for discharging a thermoplastic synthetic resin (hereinafter, referred to as “polymer”) in a film form, and 2 denotes an adjusting means for adjusting the discharge amount of the polymer from the die 1; Is a cooling drum, 4 is a control means, 5 is a film stretching device, 6 is a thickness gauge for a stretched film, 7 is an intermediate roll, 8 is a winding diameter measuring device for the intermediate roll 7, 9a is an unstretched film, and 9b is a stretched film. Film 10 indicates an oscillating amount indicating device, and 20 indicates a slit device.

In the film forming process of the present embodiment configured as described above, the polymer is melt-extruded from an extruder (not shown) and supplied to the die 1. The die 1 for discharging the molten polymer is divided into a plurality of sections having a predetermined width over the entire width, and each section is provided with each adjusting device of the adjusting means 2 for adjusting the discharge amount of the polymer. That is, by operating the adjusting means 2, the discharge amount of the polymer discharged from the die 1 can be adjusted for each section,
The discharge amount distribution of the polymer over the entire width of the die 1 can be adjusted. As a result, the thickness profile (thickness distribution in the width direction of the film) of the stretched film 9b can be finally adjusted to the initial desired thickness profile.

The adjusting means 2 includes a die 1
There is no particular limitation as long as the polymer discharge amount can be adjusted in accordance with the operation amount output from the control means 4 for each section. However, in terms of operability, maintainability, and simplification of the structure of the die 1, the polymer flow rate is changed by changing the lip temperature of the die 1 by using a heater group capable of adjusting the heating amount for each section in the adjusting device. A temperature control method of changing the temperature is preferable, and this method is used in this example.

As described above, the molten polymer is discharged from the die 1 in the form of a film while the discharge amount is controlled for each section by the adjusting means 2, cooled and solidified by the cooling drum 3, and unstretched. It becomes the film 9a.
After that, the unstretched film 9a that has been cooled and solidified is stretched in two directions, that is, in the running direction and the width direction, that is, biaxially by the stretching device 5, becomes a stretched film 9b, and is wound by a winding device (not shown). It is formed on a roll 7.

In this example, a single-layer stretched film 9b is illustrated, but in the present invention, this film may be a single-layer film or a multilayer film in which two or more layers are laminated. It may be. In this case, if the film has two or more layers, the polymer forming the film of each layer may be formed by extruding from the die 1 after being merged upstream of the die 1. Further, as in the prior art proposed in JP-A-63-120629 and the like, a plurality of polymer passages are formed in the die 1 and a plurality of polymers are merged into the passages and guided to the opening, and the polymer is introduced. It is also possible to use a composite die configured to be extruded into a multilayered film shape.

As described above, the unstretched film 9a is stretched by the stretching device 5 and
At this time, regarding the thickness of the stretched film 9b, the thickness is measured by the thickness gauge 6 at each measurement point at least in each region in the film width direction corresponding to each section where the polymer discharge amount is adjusted. It is measured and controlled as follows. That is, the control unit 4 adjusts the discharge amount of the polymer from the die 1 via the adjusting unit 2 so that the measured thickness values match the preset target value of the stretched thickness. Controlled.

In this thickness measurement, the thickness gauge 6 is measured by scanning in the width direction of the stretched film 9b. By this scanning, the thickness of the stretched film 9b is measured for each measurement point of each part to be measured. The thickness gauge 6 for a stretched film is not particularly limited as long as the thickness of the stretched film 9b can be accurately measured with required accuracy.
For example, it is preferable to use a radiation transmission type thickness meter or the like from the viewpoint of online measurement accuracy, and in this example, this radiation transmission type thickness meter was used.

In this embodiment, in addition to the thickness gauge 6 described above, the winding shape of the intermediate roll 7 formed as described above, specifically, the distribution of the winding diameter in the axial direction, in other words, in the film width direction, is shown. A winding diameter measuring device 10 for measuring is provided. The roll diameter measuring device 10 is not particularly limited as long as it can measure the outer diameter of the roll in the width direction of the film roll 7, and may be a known roll, such as a roll disclosed in JP-A-10-274511. Optical measuring means or the like for irradiating the outer diameter portion with light and measuring the outer diameter from the blocking state can be applied, and may be a contact type or a non-contact type. In the case of the contact type, the film is often damaged, and a part which cannot be formed in the product is sometimes formed. Therefore, the non-contact type is preferable. In this example, the one disclosed in the above publication was used.

The measured value of the diameter distribution of the intermediate roll 7 and the measured value of the thickness profile of the thickness gauge 6 are input to the oscillating amount indicating device 10 as shown in FIG. Calculate this, and the following intermediate roll 7
The amount of oscillate is instructed to the slit device 20 which manufactures a product roll from the product.

Incidentally, the slit device 20 of this embodiment is configured as shown in FIG. This basic configuration is the same as a known one. That is, the stretched film 9 b drawn from the intermediate roll 7 set in the rewinding section is guided to the cutter section 23 via the guide roller 22. A cutter (not shown) is arranged on the lower surface of the cutter unit 23 corresponding to the product width determined by the product specifications in the figure.
Here, the stretched film 9b is slit to the product width. Then, each part of the slit stretched film 9b is wound up by a winding machine by each touch roller 24, and 3
It is formed on individual product rolls 25 and cut-off rolls 26 at both ends.

In this example, as shown, the slit device 2
0, both end portions of a predetermined width that do not become a product in which the thickness unevenness of the intermediate roll 7 is large so as to be cut off and cut into a cut-off roll 26 and collected, and a central portion between them is used as a product portion to obtain three products. A product roll 25 having a width is manufactured. The cut-off portion may be collected in the film forming process.

In this embodiment, there is provided an oscillating device 21 for reciprocating the intermediate roll 7 set in the rewinding section in the axial direction. The oscillating device 21 reciprocates the intermediate roll 7 in the axial direction according to the oscillating amount from the oscillating amount indicating device 10.

The oscillating amount indicating device 10 is composed of a microcomputer, and determines the oscillating amount according to the specified method based on the input measurement result of the winding diameter distribution and / or thickness profile of the intermediate roll 7 as follows. And outputs it to the oscillation device 21. The oscillating amount is obtained by another computer or the like, and only the obtained oscillating instruction signal is transmitted to the oscillating amount indicating device 10.
May be set. By doing so, the oscillation amount indicating device 10 can be simplified.

Incidentally, the oscillate amount is determined by the following methods, and a method suitable for a product can be selected.

The first is a deviation averaging method. This method uses the measurement value of the winding diameter distribution of the intermediate roll 7 measured by the winding measuring device 10 as it is, and has the following configuration. First, the average value is obtained from the measured value of the winding diameter distribution. Next, the deviation from the average value is determined over the entire width.
Both ends where the deviation is equal to or greater than a predetermined cut-off value are set as cut-off portions, and a portion between the cut-off portions is set as a product portion. Then, the product part is divided into product rolls each having a product width according to the required specification, and the average value of the winding diameter and the maximum deviation from the average diameter in each product width of the product roll are determined in consideration of the winding length. Then, the oscillating amount is determined according to the averaging degree required for the product roll having the largest deviation.
That is, the oscillating amount is determined from the required degree of deviation averaging.

More specifically, in this example, the distribution near the maximum deviation is approximated by a triangle as a local convex portion from the average value, and the distribution from the base to each point on each side (more precisely, the winding diameter) is obtained. The height is defined as the local deviation, and the degree of averaging is used to reduce the deviation R by averaging.
Is specified by the ratio P to the maximum local deviation M of the vertex. According to this approximation, when the oscillation is performed with the amplitude W of the oscillation amount at a constant speed centering on the apex of the triangle, the maximum local deviation M is averaged and the deviation reduction amount R is given by the following equation. Here, the length of the base is B.

[0034]

R = M × W ÷ (B / 2) (= M × P) Accordingly, the oscillating amount W is obtained by the following equation.

[0035]

## EQU2 ## W = P × (B / 2)

From the above equation, if it is desired to reduce the maximum local deviation M to 30% by averaging, the required amount of oscillation is
0.15B. Therefore, the intermediate roll 7 may be reciprocated at least at this amplitude from the start of winding of the product roll 25 to the full winding at a constant speed in the axial direction. In some cases, it may be moved in one direction by 0.3 B in the above twice example. At this time, the moving speed is not particularly limited, but is preferably a speed that does not affect the quality of the cutter or the product. Normally, the speed is averaged at a speed of several reciprocations until full winding, including the average uniformity.

By the way, depending on the brand, the cut-off roll 2
In some cases, the end of the product roll 25 adjacent to 6 adjacent to the product roll 25 always has the maximum deviation. In such a brand, the winding diameter distribution of only the product roll portion adjacent to the cut-off roll 26 is measured, and the above method may be applied to the product roll at the end portion where the maximum deviation is large. This simplifies data processing.

During the formation of the intermediate roll 7, the distribution of the winding diameter is measured and stored at predetermined time intervals, and the oscillating amount is obtained by the above method based on the winding diameter distribution measured at the time interval. By doing so, further uniformity can be obtained. The second is a Fourier analysis method. This method obtains a deviation distribution from the average value of the measured roll diameter distribution of the intermediate roll, performs a Fourier analysis on the deviation distribution, and finds a peak where a large peak equal to or larger than a predetermined value is obtained in a predetermined frequency band applicable to averaging from a practical viewpoint. Extract the cycle,
This cycle or an integral multiple thereof is used as the amplitude of the oscillation amount. When a plurality of peaks are extracted, the average frequency obtained by weighted averaging with the peak intensity or a multiple thereof is used. The oscillation speed is determined empirically within a range that does not hinder practical use.

The third is a simulation method. In this method, the distribution of the winding diameter of the intermediate roll and the number of laminated films are measured, and the virtual thickness profile of the film forming the intermediate roll is determined from the distribution of the winding diameter and the number of laminated films. The following two methods can be selected as a method of obtaining the value.

One method is to perform a Fourier analysis on a deviation distribution from the average value of the measured roll diameter distribution of the intermediate roll, extract a peak frequency in a predetermined band as described above, and convert a sine wave of that frequency into a virtual thickness profile. It is assumed that. In addition,
When there are a plurality of peaks, the combined wave is used. The other is to obtain a winding thickness distribution of the film from the winding diameter distribution of the intermediate roll and divide the obtained distribution by the number of layers to obtain a virtual thickness profile.

Then, using the obtained virtual thickness profile, the film is simulated by a roll production model in which the film is oscillated under given oscillating conditions and the number of laminated sheets is wound by the virtual thickness profile. The outer diameter distribution of the product roll formed under different conditions is determined. Specifically, the product roll diameter is obtained by adding the number of laminations in which the virtual thickness profile is shifted by the same amount as the amount of oscillation and movement of the product roll during the time required for one rotation of the product roll. We want the distribution. Then, the oscillation is performed under the oscillating condition when the best winding diameter distribution is obtained among the obtained winding diameter distributions.

Hereinafter, a production example according to the method of the present invention will be described.

[0043]

Example 1 Raw material polymer had an intrinsic viscosity of 0.60
Of polyethylene terephthalate was used. At that time, in the polyethylene terephthalate pellets,
12 mmol of potassium acetate based on dicarboxylic acid component
%, And 0.3 wt% of kaolin having an average particle diameter of 0.9 μm was added. Then, the pellets made of the raw material polymer prepared in this manner are dried at 170 ° C. for 3 hours, and then supplied to an extruder (not shown), and are melt-extruded at 280 ° C.
And discharged from the die 1 in the form of a film. Next, the discharged polymer was cooled and solidified by being wound around a cooling drum 3 kept at 20 ° C. while applying an electrostatic charge by a known electrostatic wire (not shown) to obtain an unstretched film 9a.

The unstretched film 9a was biaxially stretched in the stretching apparatus 5 as follows. That is, first, after contacting with a heating roll (not shown) and heating to 80 ° C.,
The film is stretched 3.6 times in the longitudinal direction (running direction of the film) in a longitudinal stretching device (not shown), immediately cooled to 20 ° C., and subsequently, a tenter type transverse stretching device (not shown) is used in the transverse direction. Then, the film was stretched 5.3 times at 90 ° C., heat-treated at 120 ° C., and cooled to room temperature. Then, after the film edge portion was cut, the film was wound by a winding device to obtain a film roll 7. As the thickness adjusting unit group (adjusting means 2), the resin temperature adjusting method described above is used. The thickness adjusting unit group is divided into 30 sections over the entire width of the die 1, and the discharge amount of the polymer is determined for each section. It was arranged to be adjustable. Then, the film thickness after stretching was controlled to be uniform and 6 μm at 1.8 m in the whole width of 2.4 m in this example.

The winding diameter of the intermediate roll 7 is set to
The oscillating amount indicating device 1 also uses the winding diameter data measured by using the winding diameter measuring device described in Japanese Patent Publication No. 511 and the integrated data of the thickness measured from the start to the end of the winding by the thickness gauge 6 at the same time.
Entered into 1.

The intermediate roll 7 is provided with the oscillating amount indicating device 1.
In accordance with the instruction signal of No. 1, it is unwound while being moved in the axial direction by the oscillation device 21, slit by the cutter 23, wound by the winder, and wound into three product rolls 25.
Formed.

In the production process of the film roll,
In order to confirm the effect of the manufacturing method of the present invention, the conventional example in which the instruction signal from the oscillation amount indicating device 11 is cut off and the oscillation is not performed, and the difference between the oscillation amount indicating device 11 of the present invention and the above-described deviation averaging method is 50%. With the reduced oscillation amplitude, the oscillation speed gives the instruction signal to oscillate at the speed of reciprocating three times before the end of winding, and in both cases when the oscillation is performed, the product roll 25 is produced, and the deviation of the winding diameter and the appearance shape quality are compared. did.

The maximum roll diameter deviation of the product roll 25 of the conventional example in which the oscillation was stopped was 400 μm, and the appearance was wrinkled in some places, resulting in a defective product. On the other hand, the maximum roll diameter deviation amount of the product roll 25 in the case of the embodiment oscillated by the deviation averaging method is 50% of the conventional example, which is 200 μm, as expected, and it is a good product without wrinkles in appearance. Thus, the effect of the present invention was confirmed.

[0049]

Second Embodiment Using an intermediate roll 7 formed under the same film forming conditions as in the first embodiment, an instruction signal by the above-described Fourier analysis method is transmitted from the oscillating amount indicating device 11 in place of the deviation averaging method of the first embodiment. Produced by giving. That is, the winding diameter deviation was obtained from the measured value of the winding diameter distribution of the intermediate roll 7, and the winding diameter deviation of the intermediate roll 7 was subjected to Fourier analysis. Result 100mm
And a large peak was found at two periods of 80 mm. The magnitude of the two peaks was such that the peak intensity at a period of 80 mm was 1.2 times the peak intensity at a period of 100 mm. Therefore, the oscillation amplitude of the instruction signal is set to 89 mm which is the weighted average, and the oscillation speed is set to a speed of reciprocating 10 times before winding at this amplitude, specifically 1.0 mm / s. And was carried out.

The deviation amount of the outer diameter of the product roll 25 obtained based on this instruction signal is 210 μm at the maximum value in the first embodiment.
Although slightly worse, a good product roll 25 with a small distribution could be obtained by an easy method.

[0051]

Embodiment 3 Using the intermediate roll 7 formed under the same film forming conditions as in Embodiment 1, the thickness profile is obtained from the oscillating amount indicating device 11 by the above-described simulation method instead of the deviation averaging method of Embodiment 1. Manufactured with an indication signal by a method using Fourier analysis.

That is, as a result of Fourier analysis in the same manner as in Example 2, peaks having the same intensity were detected at periods of 100 mm and 80 mm. So 100m
A synthetic wave of a sine wave having a period of m and 80 mm is used as a virtual thickness profile, and the above-mentioned production model, specifically, the virtual thickness profile is the same as the amount oscillated for the time required for winding the product roll once. The final roll diameter deviation distribution of the product roll under each oscillating condition was obtained by a simulation in which the synthesized waves with different phases were added.

As a result, it was found that it is preferable to oscillate at an amplitude of a multiple of 90 mm and to oscillate at an interval as short as possible. The moving speed was also oscillated using the fastest oscillating rate of 1.5 mm / s as an instruction signal. The outer diameter deviation amount of the obtained product roll 25 is 180 μm at the maximum value, which is slightly better than that of Example 1, the dispersion value of the shape deviation is reduced to 1/3, and a good product roll 25 with a small distribution is obtained. Was completed.

[0054]

Fourth Embodiment Using the intermediate roll 7 formed under the same film forming conditions as in the first embodiment, the oscillating amount indicating device 11 changes the deviation averaging method of the first embodiment to a thickness profile by the above-described simulation method. It was manufactured by giving an instruction signal by a method using a winding thickness distribution.

That is, the winding thickness distribution is obtained from the winding diameter distribution,
The thickness profile per sheet obtained by dividing this by the number of layers is defined as a virtual thickness profile, and the above-mentioned production model, specifically, the virtual thickness profile is the same as the amount oscillated for the time required for winding the product roll once. The final deviation of the roll diameter of the product roll under each oscillating condition was obtained by a simulation in which the combined waves having different phases were added.

As a result, it has been found that it is preferable to oscillate with as large an amplitude as possible, and to oscillate with as short a period as possible. It was manufactured by oscillating using an oscillating condition of 5 mm / s as an instruction signal. The outer diameter deviation amount of the obtained product roll 25 was 150 μm at the maximum, and a good product roll 25 with a small distribution was able to be obtained.

[0057]

According to the present invention, the winding diameter distribution in the width direction of the intermediate film roll is measured, and an oscillating condition for averaging the deviation from the measured value of the winding diameter distribution is obtained. With a simple structure of manufacturing a product film roll by slitting while moving the film roll in the axial direction, a film roll with good winding appearance, which was difficult only by controlling the thickness in the conventional film forming process Can be formed. Therefore, it can be carried out with a small modification of the conventional apparatus, and the reject rate is reduced, and the productivity as a whole is improved.

As described above, the present invention has a great effect on the stabilization of the quality of the product roll, the improvement of the productivity, the improvement of the quality of the film roll, and the like in the production process of the film roll shipped by the roll. .

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a film roll manufacturing process according to an embodiment.

FIG. 2 is a detailed explanatory view of the slit device of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Die 2 Adjusting means 3 Cooling drum 4 Control means 5 Stretching device 6 Thickness gauge 7 Intermediate roll 8 Winding diameter measuring device 9a Unstretched film 9b Stretched film 10 Oscillate amount indicating device 20 Slit device 21 Oscillate device 22 Guide roll 23 Cutter 24 Touch Roll 25 Product roll 26 Cut-off roll

Claims (7)

[Claims] 1. A film roll manufacturing method for manufacturing a product roll by slitting a plurality of predetermined product widths while rewinding the film from an intermediate roll formed by winding up a film manufactured in a film forming process, The winding diameter distribution in the width direction of the intermediate roll is measured, and the deviation of the winding diameter distribution in each product roll after slit is obtained from the measured value of the winding diameter distribution, and the deviation of the product roll having the largest deviation is averaged. A film roll is manufactured by slitting the intermediate roll while moving the intermediate roll in the axial direction. 2. A cut-off roll without using both ends of the intermediate roll as products, and when manufacturing a product roll from the intermediate portion, a deviation of a winding diameter distribution in a product roll adjacent to the cut-off roll is obtained. The method for producing a film roll according to claim 1, wherein the deviation of the product roll having the larger value is averaged. 3. The winding diameter distribution of the intermediate roll is measured at predetermined time intervals even during the formation thereof, and a product roll having the maximum deviation is determined for each winding diameter distribution measured at the predetermined time interval. 3. The method according to claim 1, wherein a product roll for averaging the deviation of the winding diameter distribution at predetermined time intervals is switched to a product roll having the largest deviation. 4. A film roll manufacturing method for manufacturing a product roll by slitting a plurality of predetermined product widths while rewinding the film from an intermediate roll formed by winding up the film manufactured in the film forming step, Measure the winding diameter distribution in the width direction of the intermediate roll, Fourier analysis of the deviation distribution from the average value to determine the peak frequency, if there are multiple peak frequencies or the peak frequency, the weighted average of the intensity ratio A method for manufacturing a film roll, comprising manufacturing a product roll by slitting while oscillating an intermediate roll in the axial direction with a frequency or an integral multiple of these as an amplitude. 5. A film roll manufacturing method for manufacturing a product roll by slitting a plurality of predetermined product widths while rewinding the film from an intermediate roll formed by winding up the film manufactured in the film forming step, The winding diameter distribution of the intermediate roll and the number of laminated films are measured, and the virtual thickness profile of the film forming the intermediate roll is determined from the winding diameter distribution and the number of laminated films. Simulate with a roll production model that oscillates under given oscillating conditions and winds up the number of laminations, obtains the outer diameter distribution of a product roll formed by changing the oscillating conditions in the roll production model, and at least the outer diameter distribution is a product How to make a film roll that oscillates under the oscillating conditions that meet the specifications to produce a product roll Law. 6. The film roll according to claim 5, wherein the virtual thickness profile is a sine wave of a peak frequency obtained by Fourier analysis of a deviation distribution from the average value of the measured diameter distribution of the intermediate roll or a composite wave thereof. Manufacturing method. 7. The method according to claim 5, wherein the virtual thickness profile is a thickness profile obtained by dividing a winding thickness distribution obtained from a winding diameter distribution of the intermediate roll by the number of laminated layers.