JP2003201047A - Manufacturing method of resin film, and winding body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film manufacturing method of providing a winding body having no wrinkle and a good winding attitude. <P>SOLUTION: The resin film manufacturing method has a process of winding the resin film on a core while being pressed by a pressing roll. Contact pressure PE at an end in the width direction and contact pressure PC in a central part in the width direction satisfy a relation 0.5≤PE/PC<1.0. <P>COPYRIGHT: (C)2003,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and a body for winding a resin film.

[0002]

2. Description of the Related Art As a mode of holding a resin film formed in a belt shape in a film forming process, a roll wound on a core in a roll shape is generally used. In many cases, when a film is wound around a core, the film is wound by a pressing roll while removing air that has caught between the film layers.

[0003]

There are various factors that determine the quality of a roll, but a typical example is a vertical wrinkle. The main cause of the vertical wrinkles is that air which cannot be eliminated by the pressing roll and is caught between the film layers of the roll causes a slack in the roll. As a means for reducing the biting air, it is known to make the contact pressure between the pressing roll and the winding body uniform in the width direction of the resin film. this is,
By uniformly removing the biting air between the film layers in the width direction, there is an effect of preventing the biting air from locally increasing. However, the contact pressure has the effect of pushing out the surface layer of the winding body to remove the air caught between the film layers of the winding body from the end face (hereinafter referred to as air bleeding property). It was not sufficient to make the contact pressure uniform in the width direction.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a resin film, comprising a step of winding a resin film around a core while pressing it with a pressing roll. contact pressure P _C in the _E and the widthwise central portion,
This is achieved by a method for producing a resin film, characterized by satisfying a relational expression of 0.5 ≦ P _E / P _C <1.0.

Another object of the present invention is to provide a wound body in which a resin film is wound around a core, and a winding hardness H at an end in the width direction.
_E and the winding hardness H _{C at the} center in the width direction are 0.9 ≦ H _E /
This is achieved by a resin film roll that satisfies the relational expression of H _C <1.0.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the step of winding a resin film around a core while pressing with a pressing roll, the present inventors deform the pressing roll and the core by pressing force as shown in FIG. 2, for example. For this reason, it has been found that the contact pressure distribution is not as expected, and as a result, the amount of biting air is increased, which causes a problem such as wrinkles. As a result of intensive studies, the inventors have found that the contact pressure P _E at the end in the width direction and the contact pressure P _{C at the} center in the width direction are 0.
By satisfying the relational expression of 5 ≦ P _E / P _C <1.0, it has been found that air bleeding property is improved and vertical wrinkles can be prevented.

[0007] When P _E / P _C is less than 0.5, the contact pressure at the end portion with respect to the central portion is extremely insufficient, so that the biting air is increased at the end portion, causing problems such as wrinkles. When P _E / P _C is 1.0 or more, the contact pressure at the center with respect to the end is insufficient, so that not only the amount of air caught at the center increases, but also the air bleeding property decreases. In addition, problems such as vertical wrinkles occur.

[0008] As a measuring method of the contact pressure, offline
The frictional force of the contact pressure portion may be measured by a drawing method or the like, or a commercially available contact-type pressure sensor or pressure-sensitive sheet may be used.
When the contact pressure is measured online, the contact pressure may be measured by a pressure roll or a pressure sensor built in the core. The method for measuring the contact pressure is not particularly specified other than the above.

Preferably, the contact pressure decreases from the center in the width direction to the end in the width direction. Here, that the contact pressure decreases from the center in the width direction toward the end in the width direction means that the position where the contact pressure is maximum is near the center in the width direction of the resin film, and the contact pressure is minimum. Is located near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. The vicinity of the width direction end of the resin film is a range within 10% of the entire width of the resin film from the width direction end of the resin film. Even when the contact pressure does not reach the maximum in the width direction central portion, the contact pressure may be maximized in the vicinity of the width direction central portion. If the position where the contact pressure becomes maximum is in the range closer to the end than 40% of the width of the resin film in the center portion of the resin film in the width direction, the contact pressure becomes smaller in the center portion in the width direction and the air is caught in the center portion. Not only the amount increases, but also the air bleeding property decreases, which may cause problems such as vertical wrinkles.
Similarly, even if the contact pressure is not minimum at the width direction end,
What is necessary is just to make the minimum near the width direction end. If the position where the contact pressure is minimum is within a range closer to the center than 10% of the width of the resin film from the widthwise end of the resin film, the contact pressure near the end to the end is insufficient. In addition to an increase in the amount of air trapped in the vicinity of the portion, the air bleeding property also decreases, which may cause problems such as vertical wrinkles. Since the amount of air entrapment is inversely proportional to the 1/3 power of the contact pressure, the amount of air entrapment at the center in the width direction is reduced by the decrease in the contact pressure from the center to the end in the width direction. Smaller to the end. Therefore, the amount of air entrapment is small at the center in the width direction where the distance to the winding body end surface is long and air is difficult to escape. improves. Further, since the contact pressure decreases from the center to the end in the width direction, a pressure distribution in the width direction is generated between the film layers, and the biting air easily flows from the center in the width direction to the end in the width direction. Become. Therefore, the air bleeding property is improved.

[0010] The tension of the resin film in the winding body
And the tension at the width direction end is T _EAt the center in the width direction
T_C0.5 ≦ T_E/ T_C<1.
It is preferable to satisfy the relational expression of 0.

It is preferable that the tension decreases from the center in the width direction to the end in the width direction. Here, that the tension decreases from the center in the width direction toward the end in the width direction means that the position where the tension is maximum is near the center in the width direction of the resin film, and the position where the tension is minimum is the position where the tension is minimum. It means that it is near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. The vicinity of the width direction end of the resin film is a range within 10% of the entire width of the resin film from the width direction end of the resin film. Even if the tension does not become maximum at the center in the width direction, the tension may be maximum near the center in the width direction. When the position where the tension becomes maximum is in a range closer to the end than 40% of the width of the resin film in the center in the width direction of the resin film, the pressure distribution near the center is high and the pressure distribution in the center is low. In such a case, the air bleeding property is reduced, and a problem such as vertical wrinkles may occur. Similarly, even when the tension does not become minimum at the width direction end, it is sufficient if the tension is minimum near the width direction end. The position where the tension becomes minimum is
From the width direction end of the resin film, 10
%, The pressure distribution near the center is higher than that of the center, and the pressure distribution near the end is low. is there. Since the width direction tension distribution of the resin film in the winding body and the width direction pressure distribution between the film layers are proportional,
Since the tension decreases in the width direction from the center to the end, a pressure distribution in the width direction occurs between the film layers,
The biting air easily flows from the center in the width direction to the end. Therefore, the air bleeding property is improved. Where T _E / T _C
Is less than 0.5, the tension at the end portion is lower than that at the center portion, so that the resin film at the end portion may cause problems such as wrinkles. Also, T _E / T _C is 1.
In the case of 0 or more, a pressure distribution in which the pressure at the end is high and the pressure at the center is low is generated between the film layers, so that the air bleeding property is reduced and a problem such as vertical wrinkles may occur.

As a method of measuring the tension of the resin film in the roll, the film tension may be measured in the vicinity of the roll. As a specific measuring method, a plurality of tension detecting rolls may be provided in the width direction to perform the measurement, or the film may be wound around a transport roll from which pressurized air is blown from the inside, and the distance between the film and the transport roll may be measured. The width distribution may be measured by a displacement meter. Further, the tension may be measured from the frequency in the thickness direction of the film, and there is no particular limitation other than the above.

With respect to the outer diameter of the core, when the outer diameter at the center in the width direction of the core is D ₁ and the outer diameter at the end in the width direction is D ₂ , D ₁ -D ₂ is as follows: It is preferable to wind the resin film around a core that satisfies the formula.

It is preferable that the outer diameter of the core of 0.0005 × D ₁ <D ₁ −D ₂ ≦ 0.005 × D ₁ decreases from the center to the end in the width direction. The outer diameter difference D ₁ -D _{2 of the} core is 0.005.
× D ₁ is greater than, for an extreme shortage of the contact pressure of the end portion in the width direction with respect to the widthwise central portion, air biting excess at the ends which may cause problems such as wrinkles. In addition, the circumferential length difference between the center portion and the end portion in the width direction of the core becomes large, and the difference between the tension in the center portion in the width direction and the tension in the end portion in the width direction becomes excessive. Loosening of the film may similarly cause defects such as wrinkles. Also, the outer diameter difference D ₁ -D _{2 of the} core is 0.0005 ×
In the case of D ₁ or less, the outer diameter difference D ₁ -D ₂ of the core cannot absorb the amount of deflection of the pressing roll and the core, so that the contact pressure at the end in the width direction with respect to the contact pressure at the center in the width direction. Becomes larger,
As a result, the amount of air caught at the center in the width direction is larger than the amount of air caught at the end in the width direction. In other words, the amount of air entrapment is large at the center in the width direction where the distance to the end face is long and air is difficult to escape, and decreases at the end where the distance to the end face is short and air easily escapes, and the air bleeding property deteriorates. Further, since the contact pressure at the width direction end is larger than that at the width direction center, a pressure distribution in the width direction is generated between the film layers, and it becomes difficult for the biting air to flow from the width direction center to the width direction end. Therefore, the air bleeding property deteriorates.

The means for measuring the outer diameter of the core is not particularly limited, but may be a contact type measuring device such as a caliper or a π tape, or a non-contact type measuring device such as a laser displacement meter. As the shape in which the outer diameter decreases from the center in the width direction toward the end, not only a general crown shape represented by a quadratic curve but also a specific shape as long as the outer diameter profile has a clear convex shape distribution. Not done.

When the winding hardness of the winding body is H _E at the end in the width direction and H _{C at the} center in the width direction,
It is preferable to satisfy the relational expression of 0.8 ≦ H _E / H _C <1.0. Preferably, the winding hardness decreases from the center in the width direction to the end in the width direction. Here, that the winding hardness decreases from the center in the width direction toward the end in the width direction means that the position where the winding hardness is maximum is near the center in the width direction of the resin film, and the winding hardness is minimum. Is located near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. The vicinity of the width direction end of the resin film is a range within 10% of the entire width of the resin film from the width direction end of the resin film. Even when the winding hardness does not reach the maximum at the center in the width direction, the hardness may be at the maximum near the center in the width direction.
When the position where the winding hardness is maximum is in the range closer to the end than 40% of the width of the resin film at the center in the width direction of the resin film, there is more biting air in the center than in the vicinity of the center. Problems such as wrinkles may occur. Similarly, even when the winding hardness does not become the minimum at the width direction end, the winding hardness may be the minimum in the vicinity of the width direction end. If the position where the winding hardness is minimum is within a range closer to the center than 10% of the width of the resin film from the width direction end of the resin film, the biting air near the end with respect to the end increases, and the vertical length increases. Problems such as wrinkles may occur. When the winding hardness decreases from the center in the width direction to the end in the width direction, the air bite amount is
Since the distance to the end face is long, the width is small at the center in the width direction where air is difficult to escape, and the distance to the end face is small at the width direction end where air is easy to escape, indicating that the air bleeding property during winding was good. . However, if H _E / H _C is less than 0.8, the winding hardness of the end portion is lower than that of the center portion, so that excessive biting air at the end portion may cause problems such as wrinkles. If H _E / H _C is 1.0 or more, the amount of biting air in the central portion with respect to the end portion is increased, which may cause problems such as vertical wrinkles.

As a method for measuring the winding hardness, a JIS spring-type hardness tester (JIS-A) is preferable. The hardness was measured by a durometer (Shore A) or a low meter for measuring the coefficient of restitution of the surface of the wound body. The winding hardness may be converted into JIS-A.

In addition, assuming that the interlayer distance between the resin films in the surface layer of the winding body is d _E at the width direction end and d _{C at the} center portion in the width direction, d _EC is 1.0 <d _E. / D _C
It is also preferable to have an interlayer distance distribution that satisfies ≦ 1.5. The resin film interlayer distance on the winding surface layer is
It preferably increases from the center in the width direction to the end. Here, that the resin film interlayer distance increases from the center in the width direction to the end means that the position where the resin film interlayer distance is minimum is near the center of the resin film in the width direction, and the resin film interlayer distance is This means that the maximum position is near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. Further, the vicinity of the width direction end of the resin film is defined as 10 minutes of the entire width of the resin film from the width direction end of the resin film.
%. Even when the distance between the film layers is not minimum at the center in the width direction, it is sufficient if the distance between the film layers is minimum near the center in the width direction. The position where the distance between the film layers is minimum is
When the width of the resin film at the center in the width direction is closer to the end than 40% of the width of the resin film, a large amount of air is trapped in the center compared to the vicinity of the center, which may cause problems such as vertical wrinkles. is there. Similarly, even when the film interlayer distance does not become the maximum at the width direction end, the film interlayer distance may be the maximum near the width direction end. If the position where the distance between the film layers is maximum is in a range closer to the center than 10% of the width of the resin film from the widthwise end of the resin film, the air biting amount near the end to the end is large. In some cases, problems such as vertical wrinkles may occur. Since the resin film interlayer distance in the surface layer of the winding body increases from the center in the width direction to the end in the width direction, the amount of air entrapment is small in the center in the width direction where the distance to the end face is long and air is difficult to escape, Since the distance to the end face is short and there is much at the width direction end where air is easy to escape, the air escape property is improved. However, when d _E / d _C is 1.0 or less, there is a case where a problem such as a vertical wrinkle or the like occurs due to a large air bite amount in a central portion with respect to an end portion. Also d
_{If E / dC} exceeds 1.5, excessive biting air at the end with _respect to the center may cause problems such as wrinkles.

The method for measuring the interlayer distance between the resin films may be a method of measuring the pitch of interference fringes generated on the surface layer of the winding body due to the difference in refractive index between the resin film layer and the air layer to obtain the interlayer distance between the resin films, or a commercially available method. A method of measuring the interlayer distance between resin films using a thickness gauge may be used. Other measurement methods may be used.

The pressing roll in the present invention is not particularly limited, but is preferably a roll whose surface is coated with an elastic body represented by rubber.

The material of the core in the present invention is not particularly limited, but is preferably a fiber-reinforced plastic or a glass-reinforced plastic.

[0022]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic device configuration in a method for winding a resin film of the present invention. Conveyed resin film 1
Is wound around the winding core 3 by the pressing roll 2 while removing air that has caught between the film layers of the winding body, thereby forming a winding body 4. FIG. 2 is a top view of the pressing roll 2 and the core 3 in a contact pressure state. Cylinders 5 are provided at both ends of the pressing roll, and the contact pressure can be arbitrarily set within a specific range.

Examples 1-3, Comparative Examples 1-4 Pressing rolls (outer diameter 100 mm, surface length 1100 mm)
Seven kinds of FWP winding cores 1 to 7 (outer diameter 150 mm,
(Surface length: 1200 mm), and a polyester film (thickness: 4 μm, width: 1,000 mm, length: 10,000 m) was wound around the core, and the occurrence of vertical wrinkles and end wrinkles was compared. The contact pressure distribution in the width direction between the pressing roll and the winding cores 1 to 7 is shown in FIGS. 3 to 9, the abscissa represents the position in the width direction with the center in the width direction as the origin, and the ordinate represents the contact pressure per unit length in the width direction. As a measuring method of the contact pressure, a drawing method was used to obtain contact pressure data (black circles) at 11 points in the width direction. In the drawing method, a narrow-width film (a polyester film with a width of 50 mm is used in this example) is sandwiched between the contact pressure portions, and the frictional resistance force when the film is slowly pulled out in the vertical direction is measured with a push-pull. It was converted to the contact pressure per unit length in the direction. 3 to 9, the contact pressure distribution patterns are different from each other because the crown amounts of the respective cores are different as described above.

Table 1 summarizes the specifications of the winding cores and the measurement results of the contact pressure, tension and winding hardness in Examples 1 to 3 and Comparative Examples 1 to 4.

[0026]

[Table 1]

Further, Table 2 summarizes the contents of Table 1 and the occurrence of vertical wrinkles and edge wrinkles in Examples 1 to 3 and Comparative Examples 1 to 4. As criteria for determining vertical wrinkles and edge wrinkles,
Visually evaluate the appearance of the take-up roll during and after winding, and judge the level that can be shipped as a non-defective product as ○, the level that can be shipped as a defective product as △, and the level that cannot be shipped as a defective product as ×. did.

[0028]

[Table 2]

[0029]

According to the present invention as described in the foregoing, in the method for producing a resin film having a step of winding a resin film into the core while pressing at a pressing roll, the contact pressure P _E in the width direction end portion contact pressure P _C in the width direction central portion and
However, by satisfying the relational expression of 0.5 ≦ P _E / P _C <1.0, the amount of air entrainment is small at the center in the width direction where the distance to the end face is long and air is difficult to escape, and to the end. Is increased at the width direction end portion where the distance is short and air is easy to escape, and the air escape property is improved. Further, since the contact pressure decreases from the center to the end in the width direction, a pressure distribution in the width direction is generated between the film layers, and the biting air easily flows from the center in the width direction to the end in the width direction. Become. Therefore, the air bleeding property is improved.

Further, in the winding body in which the resin film is wound around the core, the winding hardness of the winding body decreases from the center in the width direction to the end in the width direction, and the winding hardness H at the end in the width direction is H.
_E and the winding hardness H _{C at the} center in the width direction are 0.9 ≦ H _E /
By satisfying the relational expression of H _C <1.0, the air entrapment amount is small at the center in the width direction where the distance to the end face is long and the air is difficult to escape, and the width direction where the distance to the end face is short and the air easily escapes is small. Since there is much at the end, the air bleeding property is improved.

[Brief description of the drawings]

FIG. 1 is a schematic device configuration in a resin film winding method of the present invention.

FIG. 2 is a top view of a schematic device configuration in the resin film winding method of the present invention.

FIG. 3 is an example of a contact pressure distribution in a width direction between a pressing roll and a core in Comparative Example 1.

FIG. 4 is an example of an aspect of a distribution of contact pressure in the width direction between a pressing roll and a core in Comparative Example 2.

FIG. 5 is an example of a contact pressure distribution in the width direction between the pressing roll and the core in the first embodiment.

FIG. 6 is an example of an embodiment of a distribution of a contact pressure in a width direction between a pressing roll and a core in a second embodiment.

FIG. 7 is an example of an aspect of a widthwise contact pressure distribution between a pressing roll and a core in a third embodiment.

FIG. 8 is an example of an embodiment of a widthwise contact pressure distribution between a pressing roll and a core in Comparative Example 3.

FIG. 9 is an example of an embodiment of a distribution of contact pressure in the width direction between a pressing roll and a core in Comparative Example 4.

[Brief description of reference numerals]

1: Resin film 2: Press roll 3: Core 4: Roll 5: Cylinder

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[Procedure amendment]

[Submission Date] May 8, 2002 (2002.5.8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

[0010] The tension of the resin film in the winding body
And the tension at the width direction end is T _EAt the center in the width direction
T_C, And 0.8≤T_E/ T_C<1.
It is preferable to satisfy the relational expression of 0.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

It is preferable that the tension decreases from the center in the width direction to the end in the width direction. Here, that the tension decreases from the center in the width direction toward the end in the width direction means that the position where the tension is maximum is near the center in the width direction of the resin film, and the position where the tension is minimum is the position where the tension is minimum. It means that it is near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. The vicinity of the width direction end of the resin film is a range within 10% of the entire width of the resin film from the width direction end of the resin film. Even if the tension does not become maximum at the center in the width direction, the tension may be maximum near the center in the width direction. When the position where the tension becomes maximum is in a range closer to the end than 40% of the width of the resin film in the center in the width direction of the resin film, the pressure distribution near the center is high and the pressure distribution in the center is low. In such a case, the air bleeding property is reduced, and a problem such as vertical wrinkles may occur. Similarly, even when the tension does not become minimum at the width direction end, it is sufficient if the tension is minimum near the width direction end. The position where the tension becomes minimum is
From the width direction end of the resin film, 10
%, The pressure distribution near the center is higher than that of the center, and the pressure distribution near the end is low. is there. Since the width direction tension distribution of the resin film in the winding body and the width direction pressure distribution between the film layers are proportional,
Since the tension decreases in the width direction from the center to the end, a pressure distribution in the width direction occurs between the film layers,
The biting air easily flows from the center in the width direction to the end. Therefore, the air bleeding property is improved. Where T _E / T _C
Is 0. If it is less than 8, the tension at the end portion becomes lower than that at the center portion, and the slack of the resin film at the end portion may cause problems such as wrinkles. Also, T _E / T _C is 1.
In the case of 0 or more, a pressure distribution in which the pressure at the end is high and the pressure at the center is low is generated between the film layers, so that the air bleeding property is reduced and a problem such as vertical wrinkles may occur.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

When the winding hardness of the winding body is H _E at the end in the width direction and H _{C at the} center in the width direction,
0. It is preferable to satisfy the relational expression of 9 ≦ H _E / H _C <1.0. Preferably, the winding hardness decreases from the center in the width direction to the end in the width direction. Here, that the winding hardness decreases from the center in the width direction toward the end in the width direction means that the position where the winding hardness is maximum is near the center in the width direction of the resin film, and the winding hardness is minimum. Is located near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. The vicinity of the width direction end of the resin film is a range within 10% of the entire width of the resin film from the width direction end of the resin film. Even when the winding hardness does not reach the maximum at the center in the width direction, the hardness may be at the maximum near the center in the width direction.
When the position where the winding hardness is maximum is in the range closer to the end than 40% of the width of the resin film at the center in the width direction of the resin film, there is more biting air in the center than in the vicinity of the center. Problems such as wrinkles may occur. Similarly, even when the winding hardness does not become the minimum at the width direction end, the winding hardness may be the minimum in the vicinity of the width direction end. If the position where the winding hardness is minimum is within a range closer to the center than 10% of the width of the resin film from the width direction end of the resin film, the biting air near the end with respect to the end increases, and the vertical length increases. Problems such as wrinkles may occur. When the winding hardness decreases from the center in the width direction to the end in the width direction, the air bite amount is
Since the distance to the end face is long, the width is small at the center in the width direction where air is difficult to escape, and the distance to the end face is small at the width direction end where air is easy to escape, indicating that the air bleeding property during winding was good. . However, H _E / H _C is 0. If it is less than 9, the winding hardness of the end portion is lower than that of the center portion, and therefore, excessive biting air at the end portion may cause problems such as wrinkles. If H _E / H _C is 1.0 or more, the amount of biting air in the central portion with respect to the end portion is increased, which may cause problems such as vertical wrinkles.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

In addition, assuming that the interlayer distance between the resin films in the surface layer of the winding body is d _E at the width direction end and d _{C at the} center portion in the width direction, d _EC is 1.0 <d _E. / D _C
It is also preferable to have an interlayer distance distribution that satisfies ≦ 1.5. The resin film interlayer distance on the winding surface layer is
It preferably increases from the center in the width direction to the end. Here, that the resin film interlayer distance increases from the center in the width direction to the end means that the position where the resin film interlayer distance is minimum is near the center of the resin film in the width direction, and the resin film interlayer distance is This means that the maximum position is near the widthwise end of the resin film. The vicinity of the central portion in the width direction of the resin film is a range within 40% of the entire width of the resin film in the central portion in the width direction of the resin film. Further, the vicinity of the width direction end of the resin film is defined as 10 minutes of the entire width of the resin film from the width direction end of the resin film.
%. Even when the distance between the film layers is not minimum at the center in the width direction, it is sufficient if the distance between the film layers is minimum near the center in the width direction. The position where the distance between the film layers is minimum is
When the width of the resin film at the center in the width direction is closer to the end than 40% of the width of the resin film, a large amount of air is trapped in the center compared to the vicinity of the center, which may cause problems such as vertical wrinkles. is there. Similarly, even when the film interlayer distance does not become the maximum at the width direction end, the film interlayer distance may be the maximum near the width direction end. If the position where the distance between the film layers is maximum is in a range closer to the center than 10% of the width of the resin film from the widthwise end of the resin film, the air biting amount near the end to the end is large. In some cases, problems such as vertical wrinkles may occur. Since the resin film interlayer distance in the surface layer of the winding body increases from the center in the width direction to the end in the width direction, the amount of air entrapment is small in the center in the width direction where the distance to the end face is long and air is difficult to escape, Since the distance to the end face is short and there is much at the width direction end where air is easy to escape, the air escape property is improved. However, when d _E / d _C is 1.0 or less, there is a case where a problem such as a vertical wrinkle or the like occurs due to a large air bite amount in a central portion with respect to an end portion. D _E
When / d _C exceeds 1.5, excessive biting air at the end with respect to the center may cause problems such as wrinkles.

Claims (6)

[Claims] 1. A resin film while pressing at a pressing roll to a method for manufacturing a resin film having a step of winding the core, the contact pressure P in the contact pressure P _E and the widthwise central portion in the width direction end portion _A method for producing a resin film, wherein _C satisfies a relational expression of 0.5 ≦ P _E / P _C <1.0. 2. The method for producing a resin film according to claim 1, wherein the contact pressure decreases from the center in the width direction to the end in the width direction. Respect wherein tension of the resin film in Makitai, tension T in the tension has been reduced toward the widthwise central portion in the width direction end portion, also the tension T _E and widthwise central portion in the width direction end portion _C is 0.8 ≦ T _E / T _C <1.0
The method for producing a resin film according to claim 1, wherein the following relational expression is satisfied. 4. An outer diameter of the core decreases from a center in the width direction toward an end in the width direction, and an outer diameter of the core at the center in the width direction is D ₁ , and an outer diameter at the end in the width direction is D ₁ . Outer diameter is D ₂
The method for producing a resin film according to claim ₁ , wherein D ₁ -D ₂ satisfies the following formula: 0.0005 × D ₁ <D ₁ −D ₂ ≦ 0.005 × D ₁ 5. A winding body in which a resin film is wound around a winding core, wherein the winding hardness of the winding body decreases from the center in the width direction to the end in the width direction, and the winding hardness at the end in the width direction. H
_E and the winding hardness H _{C at the} center in the width direction are 0.9 ≦ H _E /
A resin film roll satisfying a relational expression of H _C <1.0. 6. A resin film roll obtained by winding a resin film around a core by the method according to claim 1.