JP2020200081A - Method for storing film roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for storing a film roll, which reduces the influence of a storage environment such as a change in outside air temperature and suppresses the occurrence of wrinkles on the film roll. A method for storing a film roll, which comprises setting the storage temperature change of the film roll 3 to less than 4 ° C. per 10 minutes. A method for storing a film roll, wherein the film roll is formed by laminating a resin sheet A5 having a thermal conductivity of 0.05 W / m · K or less on the entire outer peripheral surface 4 of the film roll. A method for storing a film roll, wherein the film roll is coated with a resin sheet B9 having a metal film laminated on at least one side thereof. A method of storing a film roll, wherein the film roll is a polyester film roll. [Selection diagram] Fig. 1

Description

The present invention relates to a method for storing a film roll, which is excellent in suppressing the occurrence of wrinkles.

Conventionally, films, especially polyester films such as polyethylene terephthalate film and polyethylene naphthalate film, have excellent mechanical properties, heat resistance, and chemical resistance, and are therefore suitable as optical films, protective films, release films, and the like. In addition to being used, it is also used in the fields of general industrial materials such as packaging materials, transfer materials, magnetic tapes, electric film, and metal laminates. Such polyester films are generally stored in the form of film rolls that are wound around a paper or metal winding core.

Further, as the demand for high quality film has increased in recent years, it is known that the storage condition of the film roll affects the physical properties of the film, and the packing and storage method have been studied. For example, a packing method in which the surface of a film roll is covered with a wrap film on which a metal film is laminated, silica gel is enclosed therein to keep the humidity environment constant, and the amount of oligomer precipitation of the film is suppressed (for example, Patent Document 1 ), A packing method in which the surface of the film roll is covered with a wrap vapor deposition film and a polyethylene resin sheet to suppress deterioration of the film (for example, Patent Document 2), and a laminated wrap film made of nylon or polyethylene and a metal film are laminated. A packing method (for example, Patent Document 3) is known in which the surface of a film roll is covered with a wrap film to suppress changes in the haze and heat shrinkage of the film.

Japanese Unexamined Patent Publication No. 2004-175440 Japanese Unexamined Patent Publication No. 6-278775 Japanese Unexamined Patent Publication No. 2014-162550

However, with these methods shown in Patent Documents 1 to 3, it is possible to reduce oligomer precipitation from the film, deterioration of the film, etc., but for example, regarding deterioration of film quality and occurrence of wrinkles due to sudden changes in outside air temperature. Has not been fully considered. In view of the above circumstances, an object of the present invention is to provide a method for storing a film roll, which reduces the influence of a storage environment such as a change in outside air temperature and suppresses the occurrence of wrinkles on the film roll.

As a result of diligent studies in view of the above problems, the present inventors have found that setting the storage temperature change of the film roll to less than 4 ° C. per 10 minutes is effective in suppressing the occurrence of wrinkles on the film roll. That is, the present invention has the following configuration.
(1) A method for storing a film roll, which comprises setting the storage temperature change of the film roll to less than 4 ° C. per 10 minutes.
(2) The method for storing a film roll according to (1), wherein the film roll is formed by laminating a resin sheet A having a thermal conductivity of 0.05 W / m · K or less on the entire outer peripheral surface of the film roll.
(3) The method for storing a film roll according to (1) or (2), wherein the film roll is coated with a resin sheet B having a metal film laminated on at least one side thereof.
(4) The method for storing a film roll according to any one of (1) to (3), wherein the film roll is a polyester film roll.

According to the present invention, it is possible to provide a method for storing a film roll that is excellent in suppressing the occurrence of wrinkles.

It is a schematic diagram which shows the film roll packing body in the film roll storage method of this invention, and the packing process.

The method for storing a film roll of the present invention is characterized in that the storage temperature of the film roll is changed to less than 4 ° C. per 10 minutes. When the storage temperature of the film roll changes to 4 ° C. or higher per 10 minutes, wrinkles are likely to occur on the surface of the film roll. In the present invention, the film means a sheet-shaped molded body containing a resin as a main component, and the film roll means a film wound around a core. Further, when the storage temperature change of the film roll is less than 4 ° C. per 10 minutes, it means that the temperature change per 10 minutes is less than 4 ° C. in both the temperature raising direction and the temperature lowering direction.

Normally, the film roll is stored in a state of being packed with a resin sheet, a resin sheet on which a metal film is laminated, or the like in order to suppress the influence of heat or humidity from the outside. Examples of temperature changes in the film roll include cases where the temperature of the film roll rises and falls due to changes in the external temperature during storage in a room temperature environment where temperature control is not performed, and cases where the temperature of the film roll differs. There is an example in which the temperature of the film roll rises and falls due to the temperature difference in the environment by moving to the environment of.

In this way, the film roll is subject to external temperature changes through the packing material of the film roll. From the viewpoint of suppressing such effects and reducing wrinkles on the surface of the film roll, the change in storage temperature of the film roll is preferably less than 3 ° C., preferably less than 2 ° C., and 0 ° C. It is more preferable to set (the state where there is no temperature change). The method of setting the storage temperature change of the film roll to less than 4 ° C. per 10 minutes or the above-mentioned preferable range is not particularly limited as long as the effect of the present invention is not impaired, but for example, the resin sheet A or resin described later as a packing material for the film roll. Examples thereof include a method using the sheet B. Further, the temperature of the film roll can be measured by a known temperature / humidity data logger (stick type) with a display.

In the storage method of the film roll of the present invention, it is preferable that the film roll is formed by laminating a resin sheet A having a thermal conductivity of 0.05 W / m · K or less on the entire outer peripheral surface of the film roll. It is also preferable that the film roll is formed by coating a resin sheet B having a metal film laminated on at least one side thereof.

Further, it is preferable to have the resin sheet A and the resin sheet B in order on the entire outer peripheral surface of the film roll. In such an embodiment, the metal film of the resin sheet B suppresses the permeation of oxygen and water vapor, and the resin sheet A reduces the influence of changes in the outside air temperature, so that the film constituting the film roll has wrinkles. It can be reduced.

In the present invention, the outer peripheral surface of the film roll means a surface corresponding to the side surface of the film portion of the film roll when it is regarded as a cylinder. Having a resin sheet A and a resin sheet B on the entire outer peripheral surface of the film roll in order means that 99% or more of the outer peripheral surface of the film roll is covered with the resin sheet A and / or the resin sheet B in terms of area. A state in which the resin sheet B is located on the outside of the sheet A. Further, the principal component means a component contained in an amount of more than 50% by mass when all the constituents of the object are 100% by mass, and can be interpreted in the same manner below.

Examples of the resin that can be used for the film constituting the film roll to be stored by the method for storing the film roll of the present invention (hereinafter, may be referred to as the film in the film roll package of the present invention) include polystyrene, polyester, and the like. Examples include resins such as acrylic, polyamide, and polycarbonate. Above all, the effect of suppressing the generation of wrinkles due to the heat effect from the outside of the film when the film is rolled is particularly remarkable when the film is a polyester film. Therefore, in the method for storing the film roll of the present invention, it is preferable that the film roll is a polyester film roll. Here, the polyester film roll means a film roll in which the film constituting the film roll is a polyester film (a film containing polyester as a main component).

Polyester is a general term for polymers whose main chain is an ester bond. The polyester that can be suitably used for the film in the film roll package of the present invention is selected from, for example, ethylene terephthalate, ethylene-2,6-naphthalate, butylene terephthalate, propylene terephthalate, and 1,4-cyclohexanedimethylene terephthalate. Examples thereof include those having at least one of these constituent units as the main constituent units. Here, the main structural unit means a structural unit contained in excess of 50 mol% when all the structural units constituting the polyester are 100 mol%. The film in the film roll package of the present invention may contain only one type of these constituent resins or two or more types as long as the effects of the present invention are not impaired.

The film in the film roll package of the present invention includes various additives such as antioxidants, heat-resistant stabilizers, weather-resistant stabilizers, ultraviolet absorbers, organic lubricants, pigments, dyes, organic or inorganic fine particles. Fillers, antistatic agents, nucleating agents, cross-linking agents and the like may be added to the extent that their properties are not deteriorated.

Examples of the resin used for the resin sheet A include polyolefins such as polyethylene (thermal conductivity: 0.33 to 0.52 W / m · K) and polypropylene (thermal conductivity: 0.12 W / m · K), and polystyrene. (Thermal conductivity: 0.10 W / m · K), Polypropylene / Nylon 610 (Thermal conductivity: 0.22 W / m · K), Urethane resin (Thermal conductivity: 0.21 W / m · K), Epoxy resin (Thermal conductivity: 0.15-0.21 W / m · K) and the like. Among the above resins, polyolefin is suitable because it has excellent heat resistance and cold resistance, so that it is unlikely to have a thermal effect on the film roll, and it also has excellent ultraviolet blocking property, so that deterioration of the film roll can be reduced. .. That is, from the above viewpoint, the resin sheet A is preferably a polyolefin resin sheet.

However, since the thermal conductivity of each of the above-mentioned resins exceeds 0.100 W / m · K, more preferably, the thermal conductivity is set to 0.050 W / m · K or less and the thermal conductivity is set on the resin sheet. It is preferable to take measures to lower the temperature. As a measure for adjusting the thermal conductivity, for example, a method of forming voids inside the resin sheet can be used. The method of forming voids inside the resin sheet will be described later.

In the film roll storage method of the present invention, the resin sheet A plays a role of reducing the influence of changes in the outside air temperature. If there is no sheet corresponding to the resin sheet A, or if the entire outer peripheral surface of the film roll is covered with a sheet having a thermal conductivity of more than 0.050 W / m · K instead of the resin sheet A, the temperature of the outside air The effect of the change on the film roll becomes large, causing the film roll to have an appearance defect such as wrinkles during the storage period. In particular, when the thermal conductivity of the resin sheet covering the film roll exceeds 0.050 W / m · K, the film roll is easily affected by a sudden change in the outside air temperature, and wrinkles are generated on the surface layer thereof. Further, once wrinkles are generated on the surface layer of the film roll, the transfer of wrinkles is chained inward, so that the inner film is also wrinkled. Such wrinkles significantly affect the quality when post-processing such as hard coating is performed on the film such as an optical film. From the above viewpoint, the thermal conductivity of the resin sheet A is preferably 0.040 W / m · K or less. Further, the lower limit of the thermal conductivity of the resin sheet A is not particularly limited, but is 0.010 W / m · K from the viewpoint of feasibility.

The thermal conductivity of the resin sheet can be measured according to JIS A 1412-: 1999 6.2. The measuring machine is not particularly limited as long as it can measure, and for example, a thermal conductivity measuring device HC-074 manufactured by Eiko Seiki Co., Ltd. can be used, and specific examples of using this measuring machine. The measurement conditions and procedures are as follows. First, a resin sheet is cut into a size of 200 mm × 200 mm square to prepare a measurement sample, which is left to stand for 24 hours in a standard state of a temperature of 20 ° C. and a humidity of 65% RH. After that, the measurement sample is placed in a measuring machine, and the thermal conductivity (W / m.) Is set under the conditions of a plate temperature difference of 24 ° C. (high temperature plate temperature is 37 ° C., low temperature plate temperature is 13 ° C.) and an average temperature of 25 ° C. K) is measured.

The effects of sudden changes in the outside air temperature include the indirect transmission of the outside air temperature to the film roll through the surface packing material when the film roll package is moved from one environment to another, and the constant environment. It is caused by the outside air coming into direct contact with the film roll when the packing material is incised by moving it from below to another environment. At this time, wrinkles occur on the film roll regardless of whether the film roll is on the high temperature side or the low temperature side as compared with the external environment.

As a method of forming voids inside the resin sheet A, for example, a resin formed by adding a resin incompatible with the resin as a core material to a resin that becomes a matrix of the resin sheet at the time of manufacturing the resin sheet. Examples thereof include a method of stretching the sheet in at least one direction and a method of adding a foaming agent to the resin serving as a matrix of the resin sheet to form the sheet by extrusion. At this time, the thermal conductivity of the sheet can be lowered by increasing the porosity in the resin sheet, and in order to increase the porosity in the resin sheet, an incompatible resin or the like is used as the core material. In the above case, the amount of the core material may be increased, and when the foaming agent is used, the amount of the foaming agent may be increased. However, if the porosity is made too high, the water vapor permeability deteriorates, so that the moisture in the atmosphere permeates the resin sheet A, causing wrinkles due to moisture absorption on the surface of the film roll during storage under high humidity. Sometimes. Therefore, it is preferable to adjust the porosity of the resin sheet A so that the water vapor transmittance is within a preferable range described later.

In the storage method of the film roll of the present invention, from the viewpoint of reducing wrinkles of the film roll surface, it is preferred moisture vapor transmission rate of the resin sheet A is less than ^{100g / (m 2 · 24h)} . By water vapor permeability is less than ^{100g / (m 2 · 24h)} , it is possible to reduce the surface abnormality such as wrinkles and blocking due to moisture absorption of the film roll surface during storage under high humidity. In view of the above, it is preferred moisture vapor transmission rate of the resin sheet A is 60g ^/ (m 2 · 24h) or less. The lower limit of water vapor permeability of the resin sheet A is not particularly limited, made in view of feasibility and ^{10g / (m 2 · 24h)} .

The water vapor transmittance of the resin sheet A can be measured by the differential pressure method under the conditions of a temperature of 40 ° C., a humidity of 90% RH, and a measurement area of 50 cm ² . The measuring machine is not particularly limited as long as it can measure, and for example, a water vapor transmittance measuring device (model name: DELTAPERM (registered trademark)) manufactured by Technolox can be used.

How to water vapor permeability of the resin sheet A and 100g / (m 2 · ^24h) or less than the above preferred ranges is not particularly limited as long as it does not impair the effects of the present invention, for example, Ya method of forming a void sheet , A method of adjusting the thickness of the resin sheet A can be used. More specifically, the water vapor transmittance of the resin sheet A can be reduced by lowering the porosity of the resin sheet A and increasing the thickness of the resin sheet A.

Further, from the viewpoint of improving workability when winding the resin sheet A around the film roll, the thickness of the resin sheet A is preferably 0.1 mm or more and 5.0 mm or less. When the thickness of the resin sheet A is 0.1 mm or more, the effect of reducing the influence of changes in the outside air temperature is maintained, and when the thickness of the resin sheet A is 5.0 mm or less, the thickness of the resin sheet A is increased. Deterioration of workability of packing work due to excessive amount can be suppressed. Further, from the viewpoint of water vapor transmittance, the thickness is preferably 1.0 mm or more and 5.0 mm or less.

The thickness of the resin sheet A can be measured by dividing the value of the thickness measured with 10 resin sheets stacked by 10 according to the JIS K 7130: 1992 A-2 method using a dial gauge. it can.

In the film roll storage method of the present invention, the resin sheet B mainly plays a role of suppressing the permeation of oxygen and water vapor. The resin constituting the resin sheet B is not particularly limited, and for example, each resin such as polyolefin, polyparaffin, and polyester can be used alone or in combination of two or more. Further, the resin sheet B can be obtained by laminating a metal film on at least one surface of the sheet containing these resins as a main component. As the metal film, for example, aluminum foil, silver foil, copper foil or the like can be used, and as a method of laminating the metal film on the resin sheet, a method of laminating the above metal foil or a method of depositing these metals is used. be able to.

Next, the storage method of the film roll of the present invention will be specifically described with reference to an example in which the film roll is a biaxially stretched polyethylene terephthalate (PET) film roll, but the present invention is not limited thereto. .. Hereinafter, the melting point of PET may be referred to as Tm (° C.), and the glass transition temperature of PET may be referred to as Tg (° C.).

First, PET pellets are heated and melted by an extruder, discharged from an extrusion die into a sheet at a temperature of Tm to (Tm + 70) ° C., and rapidly cooled and solidified by a cooling drum at 20 to 90 ° C. to form an unoriented film. To get. After obtaining the non-oriented film, the film is subjected to 2.0 to 15.0 times, preferably 3.0 to 8.0 times at a temperature of (Tg-10) to (Tg + 70) ° C. in the traveling direction (longitudinal direction). It is stretched and then 2.0 to 15.0 times, preferably 3.0, at a temperature of Tg to (Tg + 70) ° C. in a direction orthogonal to the traveling direction in the plane (sometimes referred to as a lateral direction or a width direction). Stretch up to 8.0 times. Further, if necessary, it may be stretched again in the vertical direction and / or the horizontal direction. After the stretching is completed, the biaxially stretched film is thermally fixed and crystallized at a temperature of (Tg + 70) to (Tm-10) ° C. (for example, 180 to 250 ° C.) for 1 to 60 seconds to impart dimensional stability. A biaxially oriented PET film is obtained.

The obtained biaxially oriented PET film is wound around a take-up core with a running tension of the film of 200 to 300 N / m to obtain a PET film roll. As the take-up core, fiber reinforced plastic, paper, and metal can be used. The width of the PET film is not particularly limited because it depends on the film manufacturing apparatus and the slit condition in the width direction of the film, but it is generally 300 mm or more when stored as a film roll, and the film manufacturing equipment. It is generally 2,000 mm or less from the viewpoint of. The length of the film to be wound is not particularly limited, and may be, for example, 5,000 mm or more, and further 10,000 mm or more. Further, the thickness of the film is not particularly limited, and can be set to 1 μm or more and 500 μm in consideration of the intended use and the like.

Hereinafter, the film roll package is obtained by packing the obtained film roll. Hereinafter, a method for obtaining the film roll package in the film roll storage method of the present invention will be described with reference to FIG. 1 which is a schematic view showing the film roll package and the packaging process thereof. First, the biaxially oriented PET film 1 is wound on the winding core 2 on the entire outer peripheral surface 4 of the film roll 3. A foamed polyethylene resin sheet (thermal conductivity: 0.050 W / m · K or less) having voids formed as the resin sheet A5 is wound so as to overlap 50 mm or more in the longitudinal direction from the winding start portion (not shown) to the winding end portion 6. , Attach with cellophane tape 7. At this time, if necessary, the winding start of the resin sheet A may be fixed to the surface of the film roll with cellophane tape 7.

Next, the moisture absorbing material 8 is attached to the surface of the resin sheet A (the surface of the package) with cellophane tape 7 (not shown). As the hygroscopic material 8, known materials such as silica gel, potassium chloride, and potassium oxide can be used, and more specific examples thereof include OZO (moisture absorption rate 180 to 200%) of OZO Chemical Research Institute. Be done. Whether or not the hygroscopic agent 8 is provided is optional, but it is provided because the wrinkles of the film 2 caused by oxygen and water vapor that have permeated the resin sheet A5 and the resin sheet B9 (described later) can be reduced by providing the hygroscopic agent 8. Is preferable. Further, the position where the moisture absorbing material 8 is attached is arbitrary, but if the film roll 3 is directly attached, the resin sheet A5 is pressed by the resin sheet A5 provided on the outer peripheral surface 4, and the appearance of the film 2 is impaired. It is preferably between the resin sheet B9. In such an embodiment, the air interposed between the resin sheet A5 and the resin sheet B9, the air caught in the film 2 of the film roll 3, and the air that has passed through the resin sheet B9 and the resin sheet A5 can be released. It is dehumidified, and the occurrence of wrinkles on the film roll 3 (film 2) due to moisture is reduced.

After that, the film roll 3 (hereinafter, may be referred to as the film roll 10 after coating) to which the coating with the resin sheet A5 and the moisture absorbing agent 8 have been attached is covered with the resin sheet B9 having a metal film laminated on at least one side. The resin sheet B9 is not particularly limited as long as it covers the entire outer peripheral surface 4 as long as it does not impair the effect of the present invention, but both ends are opened in order to make the final package without gaps. A tube-shaped or U-shaped bag-shaped one can be preferably used (the latter aspect is shown in FIG. 1). The film roll package 11 can be obtained by binding and closing the openings of these resin sheets B with fasteners such as rubber bands and strings. The resin sheet B9, from the viewpoint of steel vapor barrier, it is preferable that the moisture permeability is 5.0g ^/ (m 2 · 24h) or less.

By storing the film roll as such a packing body, the storage temperature change of the film roll can be made less than 4 ° C. per 10 minutes. As a result, it is possible to suppress the occurrence of wrinkles on the film roll due to changes in the external environment or the like. Since the film roll storage method of the present invention can reduce the influence of oxygen and water vapor permeation and changes in the outside air temperature, it is possible to reduce the occurrence of wrinkles in the film constituting the film roll.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. The measurement method for each item is as follows.

(Evaluation method)
<Changes in film roll storage temperature and maximum storage temperature>
On the surface of the resin sheet A laminated on the surface layer of the film roll, the temperature was observed by setting the recording interval to 10 minutes using a temperature / humidity data logger (stick type) with a display manufactured by Fujita Electric Works. From the observation results, the temperature change at the timing of the largest temperature change was defined as the maximum storage temperature change (° C).

<Thermal conductivity of resin sheet>
It was measured according to JIS A 1412-: 1999 6.2. As the measuring machine, a thermal conductivity measuring device HC-074 manufactured by Eiko Seiki Co., Ltd. is used, and the specific measuring conditions and procedures are as follows. First, a resin sheet was cut into a size of 200 mm × 200 mm square to prepare a measurement sample, which was left to stand for 24 hours in a standard state of a temperature of 20 ° C. and a humidity of 65% RH. After that, the measurement sample was placed in a measuring machine, and the thermal conductivity was measured under the conditions of a plate temperature difference of 24 ° C. (high temperature plate temperature is 37 ° C., low temperature plate temperature is 13 ° C.) and an average temperature of 25 ° C. .. The same measurement was performed a total of 3 times, and the average value of the obtained values was taken as the thermal conductivity (W / m · K) of the resin sheet.

<Water vapor permeability of resin sheet>
The measurement was performed by the differential pressure method using a water vapor transmittance measuring device (model name: DELTAPERM (registered trademark)) manufactured by Technolox Co., Ltd. under the conditions of a temperature of 40 ° C., a humidity of 90% RH, and a measurement area of 50 cm ² . Measurement sample size two per level, the number of measurements is set to 5 times for each measurement sample, the mean value of the measured values of 10 times, thereby providing an water vapor permeability of the resin sheet ^{(g / (m 2 · 24h} )) ..

<Thickness of resin sheet>
Using a dial gauge, measure the thickness at any 5 locations with 10 resin sheets stacked according to the JIS K 7130: 1992 A-2 method, and divide the average value by 10 to obtain the value. Was defined as the thickness (mm) of the resin sheet.

<Evaluation of wrinkles>
The film roll package was taken out, the package was peeled off on the spot, and the presence or absence of wrinkles on the surface layer of the film roll was visually confirmed and the number of wrinkles generated was counted. When the occurrence of wrinkles was observed, the film was further unwound by 10 m or more, and the presence or absence of wrinkles was visually confirmed. Based on the obtained results, evaluation was made according to the following criteria, and ○ and △ were judged as acceptable.
〇: The number of wrinkles was 0.
Δ: The number of wrinkles generated was 1 to 2, and all wrinkles disappeared within the unwinding length of 10 m.
X: At least one wrinkle that did not disappear even when the number of wrinkles generated was 3 or more or the unwinding length was 10 m or more was observed.

(Manufacturing of biaxially oriented PET film)
The biaxially oriented PET film was produced by the following procedure. PET pellets (extreme viscosity 0.63 dl / g) containing substantially no externally added particles were sufficiently vacuum-dried and supplied to an extruder, melted at 285 ° C., and then sintered and compressed stainless steel fibers. A filter having an opening of 5 μm and a filter obtained by sintering stainless steel powder having an average opening of 14 μm were filtered in order. Then, the molten PET was extruded into a sheet from a T-shaped mouthpiece, wound around a mirror casting drum having a surface temperature of 25 ° C. using an electrostatic application casting method, and cooled and solidified. The non-oriented PET film thus obtained was heated to 90 ° C. and stretched 3.4 times in the longitudinal direction to obtain a uniaxially oriented PET film. Both ends of this uniaxially oriented PET film in the width direction are gripped with clips and guided to the preheating zone of the tenter device, dried and preheated at an ambient temperature of 120 ° C., and then continuously stretched at 120 ° C. 3.5 times in the width direction. Stretched to. The obtained PET film after biaxial stretching is subsequently heat-treated in a heating zone at 230 ° C. for 10 seconds, then subjected to a 7% relaxation treatment while cooling from 230 ° C. to 160 ° C., and subsequently cooled to 160 ° C. to 120 ° C. While re-stretching by 0.5% in the width direction, a biaxially oriented polyester film was obtained.

(Example 1)
A biaxially oriented polyester film having a thickness of 50 μm, a width of 1,300 mm and a length of 5,000 m was wound around a core made of fiber reinforced plastic (FRP) having a width of 1,400 mm and a diameter of 7 mm to obtain two polyester film rolls. .. Respectively, on the outer peripheral surface of the polyester film roll, width 1,300 mm, length 2.2 m, a polyethylene sheet having a thickness of 1 mm, the thermal conductivity of 0.330W / m · K, moisture permeability 20g ^/ (m 2 · 24h) (Corresponding to resin sheet A) was wound so as to cover the entire outer peripheral surface of the polyester film roll and to overlap the winding start and winding end by 50 mm in the longitudinal direction. At this time, the winding start portion and the winding end portion were fixed with tape so as not to move. A hygroscopic agent OZO (manufactured by OZO Kagaku Giken) was attached to both ends of the film roll with cellophane tape, centering on the inside 200 mm from the end. After that, the polyester film roll coated with the resin sheet A is inserted into a tube-shaped moisture-proof sheet (corresponding to the resin sheet B) having aluminum vapor deposition on one side, and both ends of the polyester film roll are fixed with rubber rings. A polyester film roll package of books was obtained in an environment of 10 ° C. The obtained film roll package is stored in an environment of 10 ° C. for 24 hours so that the maximum storage temperature change becomes the temperature environment change shown in Table 1, and then packed in the same environment. It was peeled off and the presence or absence of wrinkles on the surface layer of the film roll was visually confirmed. The evaluation results are shown in Table 1.

(Example 2)
On the outer peripheral surface of the polyester film roll, instead of the polyethylene sheet of Example 1, the width is 1,300 mm, the length is 2.2 m, the thickness is 1 mm, the thermal conductivity is 0.035 W / m · K, and the moisture permeability is 58 g / (m). ² · 24h) of for the use of foamed polyethylene sheet (corresponding to the resin sheet a), except that the storage temperature changes with the maximum is set to be the temperature environment changes according to Table 1 in the same manner as in example 1 The film roll package was stored for 24 hours. Then, in the same environment, the packaging was peeled off and the presence or absence of wrinkles on the surface layer of the film roll was visually confirmed. The evaluation results are shown in Table 1.

(Example 3)
The film roll package was stored for 24 hours in the same manner as in Example 2 except that the maximum storage temperature change in the storage environment temperature of Example 2 was set to be the temperature environment change shown in Table 1. Then, in the same environment, the packaging was peeled off and the presence or absence of wrinkles on the surface layer of the film roll was visually confirmed. The evaluation results are shown in Table 1.

(Comparative Example 1)
The film roll package obtained in the same manner as in Example 1 was formed in the same manner as in Example 1 except that the maximum temperature change shown in Table 1 was changed to the temperature environment change shown in Table 1. The roll package was stored for 24 hours. Then, in the same environment, the packaging was peeled off and the presence or absence of wrinkles on the surface layer of the film roll was visually confirmed. The evaluation results are shown in Table 1.

(Comparative Example 2)
The film roll package obtained in the same manner as in Example 2 was stored at the same temperature of 10 ° C. for 23 hours so that the maximum storage temperature change was 3.4 ° C., and then the constant temperature was set to 30 ° C. It was instantly carried into the tank, and immediately after removing the packaging on the spot, the presence or absence of wrinkles on the surface layer of the film roll was visually confirmed. The evaluation results are shown in Table 1.

An object of the present invention is to provide a method for storing a film roll, which reduces the influence of a storage environment such as a change in outside air temperature and suppresses the occurrence of wrinkles on the film roll. The film stored by the film roll storage method of the present invention is less likely to cause wrinkles and maintains a high-quality state, so that it can be suitably used as an optical film, a protective film, a release film, etc., and packaging. It can also be used in general industrial materials such as materials, transfer materials, magnetic tapes, electric current films, and metal laminates.

1: Biaxially oriented PET film 2: Core 3: Film roll 4: Outer peripheral surface 5: Resin sheet A
6: End of winding 7: Cellophane tape 8: Moisture absorbent 9: Resin sheet B
10: Film roll after coating 11: Film roll package

Claims (4)

A method for storing a film roll, which comprises setting the storage temperature change of the film roll to less than 4 ° C. per 10 minutes. The method for storing a film roll according to claim 1, wherein the film roll is formed by laminating a resin sheet A having a thermal conductivity of 0.05 W / m · K or less on the entire outer peripheral surface of the film roll. The method for storing a film roll according to claim 1 or 2, wherein the film roll is coated with a resin sheet B having a metal film laminated on at least one side thereof. The method for storing a film roll according to any one of claims 1 to 3, wherein the film roll is a polyester film roll.

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