Film roll package, method for manufacturing same, and method for storing or transporting film roll

Abstract

Provided is an excellent film roll packaging body capable of suppressing breakage of a packaging material of a film roll during storage and transport, further suppressing damage to the film roll, and suppressing adhesion of dust, chips, and the like. A film roll package is provided with: a film roll (13) obtained by winding a polyvinyl alcohol film (11) around a core tube (12); a packaging material (14) for packaging the film roll (13); and protective pads (16) disposed on both end surfaces of the film roll (13). Furthermore, the packaging material (14) is composed of a film containing an aluminum raw material, and the protective pad (16) is composed of a foamed member having a thickness in a specific relationship with 25% compressive stress.

Description

Technical Field

[0001] The present invention relates to a film roll package formed by winding a polyvinyl alcohol-based film around a core tube, a method for producing the film roll, and a method for storing or transporting the film roll. Background Art

[0002] In the past, polyvinyl alcohol film was manufactured as follows: polyvinyl alcohol resin was dissolved in a solvent, degassed to prepare a stock solution, then a film was formed by a solution casting method (casting method), and the film was dried using a metal heating roller, etc. The polyvinyl alcohol film obtained by the above operation is used for many purposes as a film with excellent shape stability, and one of its useful uses can be optical films, especially polarizing films.

[0003] Polarizing film is a film obtained by uniaxially stretching and dyeing the polyvinyl alcohol film, and is used as a basic component of liquid crystal displays. In recent years, the use of devices requiring high quality and high reliability, especially large-screen liquid crystal displays, has been developed, and there is a strong need for improvement of the required physical properties such as large-scale and high-quality uniformity in the plane.

[0004] In order to meet the demand for improvement of the polarizing film, the physical properties of the polyvinyl alcohol film itself as the raw material must also be improved. However, the physical and optical properties are greatly affected by the deformation of the film roll during storage and transportation, the generation of wrinkles, the adhesion of dust and dirt, and the damage of the packaging material, which leads to moisture absorption on the surface of the polyvinyl alcohol film near the end of the film roll.

[0005] Therefore, when the polyvinyl alcohol-based film is stored or transported, the film is usually wound around a core tube to form a film roll, and the film roll is handled in a state of being wrapped with a packaging film.

[0006] For example, it has been proposed that a film roll obtained by winding a polyvinyl alcohol film around a core tube longer than the width of the film be wrapped with a water vapor barrier resin packaging film, and then wrapped from above with a packaging film made of an aluminum raw material, thereby preventing winding deviation of the film roll during storage or transportation, damage to the film, and deterioration of the film due to adhesion, thereby obtaining a polarizing film with less deviation in optical performance from the winding periphery to the winding core of the film roll (see patent document 1).

[0007] In addition, if Figure 3As shown, it is proposed that: in order to cushion the impact, after installing protective pads 3 composed of a foam component with core tube through holes at both ends of a film roll formed by winding a polyvinyl alcohol film 2 around a core tube 1, the film roll is wrapped with a packaging film, and then a second protective pad is installed at both ends of the film roll from above, thereby preventing damage to the film roll during storage and transportation. Even when the film roll is used in a clean room, damage to the film roll can be suppressed, and the breakage of the polyvinyl alcohol film 2 during uniaxial stretching can be reduced (refer to patent document 2).

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Publication No. 2005-306483

[0011] Patent Document 2: International Publication No. 2013 / 103074 Summary of the invention

[0012] Problem that the invention aims to solve

[0013] Such conventional packaging forms have a certain degree of damage prevention effect and can reduce breakage during stretching, but they have not yet been able to completely suppress the occurrence of breakage, and there is still room for further improvement.

[0014] In addition, in recent years, the requirements for cleanliness in the manufacture of polarizing films and polarizing plates have been further improved, and the use of polyvinyl alcohol-based films in clean rooms has also increased. At this time, when the polyvinyl alcohol-based film is brought into the clean room, it is necessary to suppress the adhesion of dust and dirt as much as possible. However, in the previous packaging form, it is impossible to fully suppress the dust and dirt generated by the packaged materials, such as foam components, in the packaging material, and the subsequent cleaning, cross-linking, dyeing, stretching, and color correction in the manufacture of polarizers using wet stretching processing will contaminate each aqueous solution tank, and there is a concern that foreign matter will adhere to the polarizing film. In addition, there is also the following problem: the packaging material near the end of the film roll during storage and transportation is easily damaged, and due to the damage of the packaging material, the surface of the polyvinyl alcohol-based film near the end of the film roll absorbs moisture, and there is a concern that the polyvinyl alcohol-based film will break during the stretching process, resulting in a decrease in optical properties.

[0015] Furthermore, as liquid crystal displays become thinner, the expectation for further thinning of polyvinyl alcohol-based films is increasing. If the thickness of polyvinyl alcohol-based films is reduced, there are also the following problems: even damage to a degree that has not been a problem so far may cause breakage, or the length of the film roll for winding up the polyvinyl alcohol-based film becomes longer, and the frequency of foreign matter adhesion and breakage of the film roll each time it is used further increases, or the physical properties and optical characteristics of the polyvinyl alcohol-based film near the end surface of the film roll due to moisture absorption become more significantly reduced.

[0016] Solutions for solving problems

[0017] However, the inventors of the present invention have conducted in-depth research to solve the above-mentioned problems, and as a result, they have found that in a film roll packaging body in which a film roll formed by winding a polyvinyl alcohol film around a core tube is configured with a film containing an aluminum raw material and protective pads are configured on both end surfaces of the above-mentioned film roll, a material having specific physical properties can be used as the above-mentioned protective pad, thereby solving the above-mentioned problem.

[0018] That is, the present invention has the following aspects.

[0019] [1] A film roll packaging body comprising:

[0020] Film rolls made by winding polyvinyl alcohol-based films around core tubes,

[0021] The packaging material for packaging the aforementioned film roll, and

[0022] Protective pads are placed on both ends of the film roll.

[0023] The packaging material is at least composed of a film containing an aluminum raw material.

[0024] The protection pad is composed of a foam material in which the value of H in the following formula (1) is 0.18 or more.

[0025] T / K=H...(1)

[0026] [T: thickness of foamed member (mm), K: 25% compressive stress of foamed member (kPa)]

[0027] [2] The film roll package according to [1], wherein the film containing the aluminum raw material is a laminated film of a polyolefin film and an aluminum foil.

[0028] [3] The film roll package according to [1] or [2], wherein the film containing the aluminum raw material is a laminated film having a laminated structure of at least polyethylene film / aluminum foil / polyethylene film.

[0029] [4] The film roll package according to any one of [1] to [3], further comprising a second packaging material composed of a water vapor barrier film.

[0030] [5] The film roll package according to any one of [1] to [4], wherein the foam member constituting the protection pad is made of a foamed polyethylene resin.

[0031] [6] The film roll package according to any one of [1] to [5], wherein the foam material constituting the protection pad has a thickness of 3 mm or more.

[0032] [7] The film roll package according to any one of [1] to [6], wherein the 25% compressive stress of the foam member constituting the protection pad is less than 50 kPa.

[0033] [8] A method for producing a film roll packaging body, which is the method for producing a film roll packaging body according to any one of [1] to [7], comprising:

[0034] The process of installing protective pads on both ends of the film roll, and

[0035] A step of packaging the film roll to which the protective mat is attached using a packaging material made of a film containing an aluminum raw material.

[0036] [9] A method for storing or transporting a film roll, comprising storing or transporting the film roll in the form of the film roll package according to any one of [1] to [7].

[0037] Effects of the Invention

[0038] The film roll packaging body of the present invention comprises: a film roll formed by winding a polyvinyl alcohol film around a core tube, a packaging material composed of a film containing an aluminum raw material, and protective pads arranged on both end surfaces of the film roll, wherein the protective pads are composed of a special foaming member having a specific relationship between thickness and 25% compression stress, so that damage to the film roll during storage and transportation and damage to the packaging material near the end surface of the film roll can be fully prevented. In addition, when the film roll is used in a clean room, dust and dirt attached to the film roll can be suppressed, and the reduction of physical properties and optical characteristics due to moisture absorption on the surface of the polyvinyl alcohol film near the end surface of the film roll can be suppressed.

[0039] Furthermore, according to the method for manufacturing a film roll package of the present invention, the film roll package can be manufactured efficiently.

[0040] Furthermore, according to the method for storing or transporting a film roll of the present invention, the film roll can be stored or transported in a good state without damaging the packaging material of the film roll and without damaging or contaminating the film roll body. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a schematic cross-sectional view of a film roll package according to one embodiment of the present invention.

[0042] Figure 2 (a) is a schematic cross-sectional view of a protection pad used in the above-mentioned embodiment, and (b) is a schematic cross-sectional view of a modified example thereof.

[0043] Figure 3 This is an explanatory diagram showing an example of a conventional film roll packaging format. DETAILED DESCRIPTION

[0044] Hereinafter, the present invention will be described in detail based on the embodiments of the present invention, but the present invention is not limited to the following embodiments.

[0045] In the present invention, when "X to Y" (X and Y are arbitrary numbers) is expressed, unless otherwise specified, it includes the meaning of "X or more and Y or less", and the meaning of "preferably greater than X" or "preferably less than Y".

[0046] Furthermore, when expressed as "X or more" (X is an arbitrary number) or "Y or less" (Y is an arbitrary number), it also includes the meaning of "preferably greater than X" or "preferably less than Y".

[0047] Furthermore, “X and / or Y (X and Y are arbitrary structures)” means at least one of X and Y, that is, it means the following three types: only X, only Y, and X and Y.

[0048] The film roll package of the present invention mainly relates to a film roll package used in a process before manufacturing a polarizing film or a polarizing plate, and is effective during storage and transportation of the film roll package.

[0049] As a schematic cross-sectional view of one embodiment thereof Figure 1 As shown, the film roll package comprises: a film roll 13 formed by winding a polyvinyl alcohol-based film 11 wound around a core tube 12 before being stretched for use as a polarizing film, etc., a packaging material 14 composed of a film containing at least an aluminum raw material, a second packaging material 15 composed of a water vapor barrier film, and protective pads 16 arranged on both end surfaces of the film roll 13. It should be noted that Figure 1 In the figure, the constituent member indicated by reference numeral 20 is a fixing member (rubber band or the like) for fixing the second packaging material 15 to the core tube 12.

[0050] Hereinafter, each component of the film roll package will be described.

[0051] <Film roll 13>

[0052] First, the polyvinyl alcohol-based film 11 constituting the film roll 13 and the core tube 12 around which the film is wound will be described.

[0053] (1) Polyvinyl alcohol film 11

[0054] The polyvinyl alcohol resin used in the manufacture of the aforementioned polyvinyl alcohol film 11 is usually obtained by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate, but it is not necessarily limited to this. It can also be a modified polyvinyl alcohol resin containing a small amount of unsaturated carboxylic acid (including salts, esters, amides, nitriles, etc.), olefins with a carbon number of 2 to 30 (ethylene, propylene, n-butene, isobutylene, etc.), vinyl ethers, unsaturated sulfonates, and other components that can be copolymerized with vinyl acetate.

[0055] In addition to this modification, the polyvinyl alcohol-based resin may contain a silyl group. Examples of the methods include post-modification of polyvinyl alcohol using a silylating agent, saponification of a copolymer obtained by copolymerizing an ethylenically unsaturated monomer containing a silyl group with vinyl acetate, and the like. Examples of the ethylenically unsaturated monomer containing a silyl group include vinyl silane, (meth)acrylamide-alkyl silane, and the like.

[0056] The weight average molecular weight of the polyvinyl alcohol resin is not particularly limited, but is preferably 60,000 to 300,000, and more preferably 100,000 to 260,000. If the weight average molecular weight is less than 60,000, sufficient optical performance as an optical film cannot be obtained, and if it exceeds 300,000, stretching becomes difficult, and industrial production is difficult and not preferred. It should be noted that the weight average molecular weight is measured by the GPC-MALS method.

[0057] Furthermore, the saponification degree of the polyvinyl alcohol-based resin is preferably 80 mol% or more, more preferably 85 to 100 mol%, and even more preferably 98 to 100 mol%. By setting the saponification degree as described above, sufficient optical performance as an optical film can be obtained. It should be noted that the saponification degree is measured in accordance with JIS K 6726:1994.

[0058] The polyvinyl alcohol resin may contain, as required, 30 parts by mass or less of one or more commonly used plasticizers such as glycerol, diglycerol, triglycerol, ethylene glycol, triethylene glycol, polyethylene glycol, etc., more preferably 3 to 25 parts by mass, and even more preferably 5 to 20 parts by mass, relative to 100 parts by mass of the polyvinyl alcohol resin. By setting the content of the plasticizer to the above range, it is possible to suppress the reduction in film strength.

[0059] In addition, in order to improve the releasability of the film, it is preferred to contain 5 parts by mass or less of one or more kinds of various release agents, more preferably 0.001 to 3 parts by mass, and further preferably 0.001 to 2 parts by mass, relative to 100 parts by mass of the polyvinyl alcohol-based resin. By setting the release agent to the above range, it is possible to suppress the poor appearance of the film surface and to suppress the adhesion between the films.

[0060] The polyvinyl alcohol film 11 used in the present embodiment can be obtained by preparing a polyvinyl alcohol resin aqueous solution using the polyvinyl alcohol resin, casting the aqueous solution onto a drum roll using a T-slit die, and performing film formation and drying.

[0061] It should be noted that, when preparing the above-mentioned polyvinyl alcohol resin aqueous solution, water, dimethyl sulfoxide (DMSO), N-methylpyrrolidone, glycerol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, trimethylolpropane and other polyols, amines such as ethylenediamine and diethylenetriamine, and mixtures thereof are used as solvents. It is practical to set the concentration of the polyvinyl alcohol resin in the polyvinyl alcohol resin aqueous solution to 5 to 50% by mass.

[0062] Then, the polyvinyl alcohol-based resin aqueous solution is cast onto a drum roll using a T-slit die to form a film at a temperature of about 80 to 100°C.

[0063] The material of the drum roller is not particularly limited, and stainless steel is usually suitable. In order to prevent damage, it is preferred to apply metal plating to the roller surface. As the type of metal plating, for example, chrome plating, nickel plating, zinc plating, etc. can be used appropriately. They can be used alone or in the form of a multilayer combination of two or more. In particular, from the perspective of ease of surface smoothing and durability, chrome plating is preferably used on the outermost surface. The surface roughness (according to JIS B 0031: 1994 method) is preferably 3S or less, and more preferably 0.5S or less. The lower limit is usually 0S.

[0064] The drum roll may be heated by steam, heat medium, warm water, electric heater, etc. In addition, an auxiliary device for blowing hot air, cold air, etc. or sucking air and steam around the device may be used. The diameter of the drum roll is preferably 2,000 to 5,000 mm, and the width is preferably 2 to 8 m. When the moisture content of the film reaches 5 to 30% by mass, it will peel off the drum roll.

[0065] Then, after the film obtained by the film casting is peeled off from the drum roll, the film is passed through a drying metal roll, preferably between a plurality of drying metal rolls in a manner that the film surface and the back surface alternately pass along the circumference of the roll, to be dried. A plurality of drying metal rolls are used, preferably 3 to 30, particularly preferably 3 to 26.

[0066] The material of the aforementioned metal roller for drying is not particularly limited, as is the case with the drum roller. From the perspective of ease of surface smoothing and its durability, it is preferred that the outermost surface is chrome-plated and the surface roughness is 3S or less, and more preferably 0.5S or less. The lower limit is usually 0S. Moreover, the diameter of the aforementioned metal roller for drying is preferably 100 to 1,000 mm, and the width is preferably 2 to 8 m. It is practical for the temperature of the aforementioned metal roller for drying to be 50 to 150°C, and a temperature gradient and a rotation speed difference may be appropriately applied between the rollers.

[0067] The heating method of the aforementioned drying metal roller also can adopt steam, thermal medium, warm water, electric heater etc. equally with drum roller. In addition, also can be provided with the auxiliary device that is used to blow hot air, cold wind etc. or the air on the suction device, steam.

[0068] When manufacturing a film, if the wetting tension on the surface of the drum roller and / or the metal roller for drying is adjusted to 25 to 50 mN / m, the film can be manufactured with good productivity. The wetting tension is measured in accordance with JIS K 6768:1999. The method for setting the wetting tension to the aforementioned range is not particularly limited, and (A) a roller having a mirror-finished chrome surface is used, and the surface is treated with an acid aqueous solution of pH 1 to 3 (measured at 20°C, the same below). Examples of the acid aqueous solution of pH 1 to 3 include aqueous solutions of acetic acid, sulfuric acid, hydrochloric acid, nitric acid, etc., among which aqueous solutions of acetic acid and nitric acid are particularly preferred. Acid aqueous solutions having a pH outside the aforementioned range are not easy to obtain a wetting tension within the aforementioned range.

[0069] In addition to treating the roller surface with an acid aqueous solution as in (A), as a method for adjusting the wetting tension, (B) a surfactant may be added to an aqueous solution of a polyvinyl alcohol-based resin in advance, and the aqueous solution may be cast onto a drum roller to form a film and / or the obtained film may be dried with a metal roller for drying so that the film is formed under the condition that the wetting tension on the roller surface is within the above range. In addition to improving the uniformity of the film thickness and the film appearance characteristics, adjusting the wetting tension in this way is preferred from the viewpoint of further improving the long-term film forming property.

[0070] The amount of the surfactant added is not particularly limited, but is preferably 0.001 to 5 parts by mass, more preferably 0.01 to 2 parts by mass, and further preferably 0.01 to 1 part by mass relative to 100 parts by mass of the polyvinyl alcohol resin. By setting the amount added within the above range, it is possible to prevent the difficulty in adjusting the wet tension or the problem of film blocking.

[0071] Examples of the surfactant include carboxylate-type surfactants such as fatty acid soaps, N-acylamino acids and salts thereof, polyoxyethylene alkyl ester carboxylates, and acylated peptides; sulfonate-type surfactants such as alkylbenzenesulfonates, alkylnaphthalenesulfonates, formaldehyde condensate salts of naphthalenesulfonic acid, formaldehyde condensate salts of melaminesulfonic acid, dialkyl sulfosuccinate salts, alkyl sulfosuccinate disalts, polyoxyethylene alkyl sulfosuccinate disalts, alkyl sulfoacetates, α-olefin sulfonates, N-acylmethyltaurates, and dimethyl isophthalate-5-sulfonic acid sodium salt; sulfated oils, higher alkyl sulfate ester salts, polyoxyethylene alkyl ether sulfates, higher alcohol ethoxysulfates, polyoxyethylene alkylphenyl ether sulfates, and monoglycerol sulfate; and anionic surfactants such as phosphate ester salts such as polyoxyethylene alkyl ether phosphates, polyoxyethylene alkylphenyl ether phosphates, and alkyl phosphates.

[0072] In addition, as the above-mentioned surfactant, ether ester type nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, ethylene oxide derivatives of alkylphenol formaldehyde condensation products, polyoxyethylene polyoxypropylene block polymers, polyoxyethylene glycerol fatty acid esters, polyoxyethylene castor oil and hydrogenated castor oil, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, ester type surfactants such as polyethylene glycol fatty acid esters, sorbitan fatty acid esters, fatty acid monoglycerides, propylene glycol fatty acid esters, sucrose fatty acid esters, higher fatty acid alkanolamides, higher fatty acid amides, polyoxyethylene alkylamines, etc. can also be used. These can be used alone or in combination of two or more. When implementing the method of the present invention, of course, the two methods (A) and (B) described above can be used in combination to form a film.

[0073] Then, after drying to form an unstretched polyvinyl alcohol-based film, heat treatment and humidity control are further performed as necessary. In this way, the polyvinyl alcohol-based film 11 used in the present embodiment can be obtained.

[0074] The obtained polyvinyl alcohol-based film 11 is wound around a core tube 12 to be described later, thereby obtaining a film roll 13 in the present embodiment.

[0075] The width of the polyvinyl alcohol film 11 is preferably set to be 1 m or more, more preferably set to be 2 m or more, further preferably set to be 3 m or more, and particularly preferably set to be 4 m or more. In addition, it is preferably 7 m or less, and more preferably 6 m or less. By setting the width of the polyvinyl alcohol film 11 to the aforementioned range, the influence of the shrinkage of the film during the manufacture of an optical film such as a polarizing film can easily reach the central part of the film, and a good optical film can be obtained.

[0076] In addition, if the length of the polyvinyl alcohol film 11 is 4,000 m or more, the effect of the present invention can be significantly obtained. It should be noted that if the length is less than 1,000 m, the number of joints in the obtained polarizing film increases and the loss increases. In addition, the thickness of the polyvinyl alcohol film 11 is 10 to 100 μm, which is practical, preferably 10 to 70 μm, more preferably 10 to 50 μm, and further preferably 10 to 40 μm. By setting the thickness to the aforementioned range, it is possible to suppress the situation where stretching at a high ratio becomes difficult.

[0077] (2) For core tube 12

[0078] The core tube 12 wound by the aforementioned polyvinyl alcohol-based film 11 is cylindrical, and its material can use any material such as metal, plastic, paper, etc. As metal, can list: carbon steel, high-tensile steel, stainless steel, aluminum, aluminum alloys such as hard aluminum, copper, brass, bronze, etc. For such a metal core tube 12, soft polyvinyl chloride, low-density polyethylene can also be stacked or implemented using nickel, chromium, zinc, tin, etc. plating treatment. In addition, as plastic, can list: hard polyvinyl chloride, polypropylene, high-density polyethylene, ultra-high molecular weight polyethylene, polycarbonate, polyester, fiber reinforced plastic, carbon fiber reinforced plastic, aramid fiber reinforced plastic, etc.

[0079] The outer diameter of the core tube 12 is preferably 7.5 cm or more, more preferably 8.5 cm or more. By setting the outer diameter of the core tube 12 to the above, wrinkles in the film can be suppressed. The length of the core tube 12 needs to be longer than the width of the polyvinyl alcohol film 11, and is preferably set to protrude 1 to 50 cm from the end of the film roll 13.

[0080] Brackets are provided at both ends of the protruding portion or the two ends of the protruding portion are placed on a bracket, etc., so that the film roll 13 is in a state of floating in the air without contacting the ground or other film rolls, thereby preventing the load of the film roll 13 from being applied to the wound polyvinyl alcohol film 11, and can suppress the adhesion and deterioration of the polyvinyl alcohol films 11. The wall thickness of the core tube 12 is preferably 1.5 to 20 mm, more preferably 2 to 15 mm, and further preferably 3 to 10 mm.

[0081] <Protective pad 16>

[0082] The protective pads 16 disposed on both end surfaces of a film roll 13 in which the polyvinyl alcohol film 11 is wound around a core tube 12 are made of a foam material.

[0083] The foam material used in the protection pad 16 is not particularly limited as long as it has a foam structure, but the important thing is that the value of H in the following formula (1) is 0.18 or more, preferably 0.2 or more, more preferably 0.24 or more, and even more preferably 0.26 or more.

[0084] T / K=H...(1)

[0085] [T: thickness of foamed member (mm), K: 25% compressive stress of foamed member (kPa)]

[0086] The value of H is preferably 4 or less, more preferably 3 or less, and even more preferably 2 or less.

[0087] That is, if the value of H is within the above range, when an impact or load is applied to the film roll package from the outside, the protective pad 16 can appropriately mitigate the impact, thereby preventing the packaging material 14 that packages the film roll 13 from being damaged and broken. In addition, the polyvinyl alcohol film 11 that is packaged inside can be prevented from absorbing moisture.

[0088] The thickness (T) of the foam material is preferably 3 mm or more, more preferably 7 mm or more, and even more preferably 9 mm or more. By setting the thickness within the above range, damage to the end surface of the film roll 13 can be more effectively prevented.

[0089] The upper limit of the thickness of the aforementioned foaming member is not particularly limited. From the viewpoint of handleability, the thickness is preferably 30 mm or less, more preferably 25 mm or less, and further preferably 20 mm or less. It should be noted that when it is difficult to ensure that one foaming member is the aforementioned thickness, multiple foaming members can be overlapped to ensure the aforementioned thickness in the form of total thickness.

[0090] In addition, the 25% compressive stress (K) of the aforementioned foaming member is preferably 5 kPa or more, more preferably 7 kPa or more, and further preferably 10 kPa or more. Moreover, the upper limit of the 25% compressive stress of the aforementioned foaming member is preferably set to less than 50 kPa, more preferably set to less than 47 kPa, further preferably set to less than 45 kPa, and particularly preferably set to less than 42 kPa. By setting the 25% compressive stress of the foaming member to the aforementioned range, damage to the end surface of the film roll can be more effectively suppressed.

[0091] In addition, the 25% compressive stress of the said foam material can be measured according to JIS K 7220:2006 method.

[0092] Furthermore, the water absorption rate of the foamed material is preferably 0.05 g / cm 2 Below, more preferably 0.03 g / cm 2 Below, more preferably 0.015 g / cm 2By setting the water absorption rate to the above range, the foamed member absorbs the water in the polyvinyl alcohol film, thereby preventing the polyvinyl alcohol film from having uneven water content and the polyvinyl alcohol film from being easily broken during uniaxial stretching. In addition, there is no particular lower limit to the water absorption rate, but the lower the water absorption rate, the harder the film becomes, and the lower the cushioning function. Therefore, the water absorption rate is preferably 0.0002 g / cm 2 It should be noted that the water absorption rate in this specification refers to the water absorption rate obtained by the measurement method described in JIS A9511: 2006R, A method.

[0093] Furthermore, the foam member may be formed of a foam plastic having closed cells or a foam plastic having open cells.

[0094] However, the polyvinyl alcohol film 11 in the film roll packaging body is sometimes controlled in such a way that the moisture content in the film is within a specified range. If a foaming component composed of a foamed plastic with continuous bubbles is used, the moisture content in the polyvinyl alcohol film 11 changes due to the influence of the water absorption rate of the foaming component. Therefore, in this case, it is preferred to use a foamed plastic with independent bubbles as the foaming component.

[0095] The material of the foaming member is not particularly limited, and for example, a foaming member formed of a foamed plastic resin such as a foamed polyethylene resin, a foamed polystyrene resin, a foamed polyurethane resin, or a foamed polyvinyl chloride resin can be used. However, if a foaming member of a material whose water absorption rate is easily increased is used as described above, it becomes difficult to suppress the change in the water content in the polyvinyl alcohol film 11 in the package body. When such suppression is required, it is preferred to use a foaming member formed of a foamed polyethylene resin whose water absorption rate is easily suppressed to a low level.

[0096] It should be noted that, in the aforementioned protection pad 16, as shown in the schematic enlarged cross-sectional view thereof, Figure 2 As shown in (a), from the viewpoint of preventing contamination and damage to the film roll 13, it is preferred to provide a non-foamed resin layer 18 on the surface of the protective pad 16 opposite to the end surface of the polyvinyl alcohol film 11 (i.e., the end surface side of the film roll 13).

[0097] In addition, if Figure 2 As shown in (b), from the viewpoint of preventing contamination and damage to the film roll 13, it is more preferable to also provide the aforementioned non-foamed resin layer 18 on the surface opposite to the end surface of the polyvinyl alcohol film 11 (i.e., the end surface portion of the film roll 13).

[0098] The material of the non-foamed resin layer 18 is not particularly limited, and common resins can be used, such as polyethylene resins, polypropylene resins, polyvinyl chloride resins, polycarbonate resins, polyester resins, acrylic resins, polyvinyl alcohol resins, polyacrylamide resins, polyamide resins, fluorine resins, etc. Among them, from the viewpoint of excellent strength and flexibility, polyolefin resins are preferred, and polyethylene resins are more preferred.

[0099] The thickness of the non-foamed resin layer 18 is preferably 5 μm or more, more preferably 8 μm or more, and further preferably 12 μm or more. By setting the thickness of the non-foamed resin layer 18 as described above, it is possible to suppress the transfer of the surface shape of the foamed member used in the protective pad 16 and the generation of fine irregularities on the surface of the non-foamed resin layer 18, and to suppress dust, chips, etc. from adhering to the irregularities. Furthermore, the generation of chips caused by friction with the end surface of the film roll 13 can be suppressed.

[0100] In addition, the thickness of the non-foamed resin layer 18 is preferably 500 μm or less, more preferably 300 μm or less, further preferably 100 μm or less, further preferably 80 μm or less, particularly preferably 60 μm or less, and particularly preferably 50 μm or less. By setting the thickness of the non-foamed resin layer 18 as described above, the tensile strength of the non-foamed resin layer 18 can be made appropriate, and damage to the end face of the film roll 13 when external loads and impacts are transmitted to the film roll 13 through the foaming member, film bending near the end face of the wound polyvinyl alcohol film 11, and film thickness changes can be suppressed.

[0101] The thickness of the non-foamed resin layer 18 is measured by observing a cross section using a microscope, and the average value of the thicknesses at 10 random locations is taken as the thickness value.

[0102] The surface roughness Ra (arithmetic mean roughness according to JIS B 0601:1994 method) of the non-foamed resin layer 18 is preferably 0.01 μm or more, more preferably 0.05 μm or more, and further preferably 0.1 μm or more. In addition, it is preferably 5 μm or less, more preferably 3 μm or less, and further preferably 1 μm or less. By setting the surface roughness Ra of the non-foamed resin layer 18 as described above, dust, shavings, etc. can be easily attached to the surface unevenness or the attached matter can be prevented from entering between the unevenness and becoming difficult to remove.

[0103] It should be noted that the measurement conditions of the surface roughness are as follows: the measurement length is 1 mm, the stylus shape is: the tip radius is 2 μm, and the taper angle is 60 μm.

[0104] The surface roughness Ry (maximum height according to JIS B 0601:1994 method) of the non-foamed resin layer 18 is preferably 0.1 μm or more, more preferably 0.5 μm or more, and further preferably 1 μm or more. In addition, it is preferably 8 μm or less, more preferably 6 μm or less, and further preferably 4 μm or less. By setting the surface roughness Ry of the non-foamed resin layer 18 as described above, dust, shavings, etc. are easily attached to the surface unevenness or the attached objects enter between the unevenness and become difficult to remove. Such a situation can be suppressed.

[0105] The surface roughness Rz (using JIS B 0601:1994 method, ten-point average roughness) of the non-foamed resin layer 18 is preferably 0.1 μm or more, more preferably 0.5 μm or more, and further preferably 1 μm or more. In addition, it is preferably 8 μm or less, more preferably 6 μm or less, and further preferably 4 μm or less. By setting the surface roughness Rz of the non-foamed resin layer 18 as described above, dust, shavings, etc. tend to adhere to the surface concave-convex or the attached objects enter between the concave-convex and become difficult to remove, which can be suppressed.

[0106] The method for joining the non-foamed resin layer 18 and the protection pad 16 including the foamed member is not particularly limited, and an appropriate method is adopted according to the materials of the non-foamed resin layer 18. For example, the two may be joined using an adhesive, or the two may be melt-bonded by a heated roller in a state where the foamed sheet as the protection pad 16 and the resin sheet as the non-foamed resin layer 18 are overlapped with each other. In addition, when the protection pad 16 is obtained using a foamed sheet, the surface layer portion of the foamed sheet may be pressed with a heated roller to form a non-foamed surface layer, thereby forming the protection pad 16 and the non-foamed resin layer 18 as a whole.

[0107] <Packaging material 14>

[0108] The packaging material 14 used in the present embodiment is composed of a film containing an aluminum raw material. Examples of such films include aluminum foil, a laminated film of aluminum foil and a moisture-resistant plastic film (e.g., a laminated film of aluminum foil and a polyethylene film), a laminated film of an aluminum vapor-deposited film and a moisture-resistant plastic film (e.g., a laminated film of an aluminum vapor-deposited polyester film and a polyethylene film), a laminated film of an aluminum oxide vapor-deposited film and a moisture-resistant plastic film (e.g., a laminated film of an aluminum oxide vapor-deposited polyester film and a polyethylene film), etc., and in particular, a laminated film of aluminum foil and a polyolefin film, a laminated film of an aluminum vapor-deposited film and a polyolefin film, and particularly preferably a laminated film composed of a stretched polypropylene film / polyethylene film / aluminum foil / polyethylene film, and a laminated film composed of a stretched polypropylene film / low-density polyethylene film / aluminum foil, etc.

[0109] By using such a packaging film containing aluminum raw materials as the aforementioned packaging material 14, the generation of pinholes in the layer of aluminum raw materials can be suppressed, and it becomes less likely that the water vapor barrier property will be reduced. After the film roll 13 is packaged with the packaging material 14, the film roll can be sealed in a roughly tubular shape using methods such as heat sealing, which can more effectively suppress water from penetrating into the film roll package.

[0110] In the aforementioned packaging material 14, when aluminum foil is used as the aforementioned aluminum raw material, the thickness of the aluminum foil is preferably set to 30 μm or less, more preferably set to 20 μm or less, further preferably set to 15 μm or less, particularly preferably set to 10 μm or less, and particularly preferably set to 8 μm or less. In addition, it is preferably set to 1 μm or more, more preferably set to 3 μm or more, and further preferably set to 5 μm or more. By setting the thickness of the aluminum foil as described above, the generation of pinholes can be suppressed, and then the packaging material 14 can be given flexibility, the handling of the packaging material 14 during packaging is easy to carry out, and the packaging workability is improved. It should be noted that the load and impact applied from the outside of the film roll package are released with appropriate strength to exert a buffering effect, thereby suppressing the generation of scratches and damage to the polyvinyl alcohol film 11 as the content.

[0111] <Second packaging material 15>

[0112] In this embodiment, the second packaging material 15 used together with the packaging material 14 is composed of a water vapor barrier film. In this example, the second packaging material 15 is arranged inside the packaging material 14 (on the film roll 13 side).

[0113] The water vapor barrier film constituting the second packaging material 15 is not particularly limited as long as it has water vapor barrier properties, and a suitable water vapor permeability of 10 g / m 2 / day (measured according to JIS Z 0208: 1976 method) or less. Specific examples include: single-layer films of high-density polyethylene resins, low-density polyethylene resins, polypropylene resins, polyester resins, polyvinyl chloride resins, glass-deposited polyester resins, etc., or laminated films thereof, or laminated films with rags, paper, and non-woven fabrics, etc. Laminated films include: laminated films of glass-deposited polyester and polyethylene, etc.

[0114] The thickness of the water vapor barrier film is not particularly limited, but is preferably 100 μm or less, more preferably 70 μm or less, further preferably 50 μm or less, and particularly preferably 40 μm or less. In addition, it is preferably 5 μm or more, more preferably 10 μm or more, and further preferably 15 μm or more. By setting the thickness of the water vapor barrier film as described above, water vapor barrier properties can be imparted, and the occurrence of tearing caused by impact or the like can also be suppressed. Moreover, the softness becomes excellent, and the handling property during packaging becomes preferred.

[0115] In addition, the aforementioned water vapor barrier film is also suitable for antistatic treatment. That is, if the antistatic treatment is performed in advance, it is possible to prevent foreign matter from being mixed in as a cause of breakage when the polyvinyl alcohol film 11 is stretched to produce the polarizing film. As a method of antistatic treatment, it is possible to mix an antistatic agent in the aforementioned water vapor barrier film or to coat the surface of the film with a coating containing an antistatic agent. When mixing, an antistatic agent is used in an amount of about 0.01 to 5% by mass relative to the resin, and when coating the surface, 0.01 to 1 g / m 2 There are no particular restrictions on the antistatic agent as long as it does not adversely affect the optical properties, and examples thereof include alkyldiethanolamine, polyoxyethylene alkylamine, higher fatty acid alkanolamide, and sorbitan fatty acid ester.

[0116] <Film roll packaging>

[0117] When the film roll packaging body of the present embodiment is obtained using the aforementioned constituent components, for example, first, for the film roll 13 formed by winding the polyvinyl alcohol film 11 around the core tube 12, protective pads 16 having core tube through holes are respectively installed on both end faces thereof so as to be opposed to the end faces of the film roll 13. Then, the film roll 13 is packaged using the second packaging material 15 composed of a water vapor barrier film, and the excess ends in the width direction are squeezed along the core tube 12 and tied with a rubber band 20. Then, the entirety is packaged using the packaging material 14 composed of a film containing an aluminum raw material (hereinafter, also referred to as an "aluminum film"), and the excess ends in the width direction are sealed along the core 12. In this way, a structure arranged in the order of "film roll 13 / protective pad 16 / second packaging material 15 (water vapor barrier film) / packaging material 14 (aluminum film) / outside of packaging body" can be obtained (refer to Figure 1 ) film roll packaging body.

[0118] It should be noted that the order of packaging is not limited to this example, and other examples include, for example, arranging from the inside of the package (film roll 13 side) toward the outside of the package as described below.

[0119] · The film roll 13 / protection pad 16 / packaging material 14 (aluminum film) / second packaging material 15 (water vapor barrier film) / outside of the packaging body are arranged in this order

[0120] · The film roll 13 / packaging material 14 (aluminum film) / protection pad 16 / second packaging material 15 (water vapor barrier film) / outside of the packaging body are arranged in this order

[0121] · The film roll 13 / packaging material 14 (aluminum film) / second packaging material 15 (water vapor barrier film) / protection pad 16 / outside of the packaging body are arranged in this order

[0122] · The film roll 13 / the second packaging material 15 (water vapor barrier film) / the packaging material 14 (aluminum film) / the protective pad 16 / the outer side of the packaging body are arranged in this order

[0123] In addition to these aspects, a second protection mat (which may be the same as the protection mat 16 of the present embodiment or another protection mat having a different structure) may be attached to the outermost side of the package body.

[0124] Furthermore, in the above-mentioned embodiment, the packaging material 14 composed of an aluminum film is used in combination with the second packaging material 15 composed of a water vapor barrier film, but it is not necessary to use the above-mentioned second packaging material 15 (water vapor barrier film). In this case, as the arrangement of the packaging body, for example, the following arrangement can be listed.

[0125] · The film roll 13 / protection pad 16 / packaging material 14 (aluminum film) / outer side of the packaging body are arranged in this order

[0126] · The film roll 13 / packaging material 14 (aluminum film) / protection pad 16 / outer side of the packaging body are arranged in this order

[0127] · In these methods, a method in which a second protective pad as described above is further installed on the outside

[0128] It should be noted that, in the aforementioned methods, the packaging material 14 (aluminum film), the second packaging material 15 (water vapor barrier film), and the protective pad 16 may also have a multi-layer structure respectively. For example, " / packaging material 14 (aluminum film) / " means that it can be any of a packaging material 14 (aluminum film) with only one layer, a packaging material 14 with more than two layers, or more than two packaging materials 14 with one layer or more than two layers respectively.

[0129] Moreover, among these specific forms of the film roll packaging body, particularly from the perspective of ease of manufacturing the packaging body and the ability to protect the end surface of the film roll 13 until the equipment is set in the process of polarizing film, it is particularly preferred to arrange the packaging body in the order of "film roll 13 / protection pad 16 / packaging material 14 (aluminum film) / outside of the packaging body" from the inside to the outside of the packaging body, the method of arranging the packaging body in the order of "film roll 13 / protection pad 16 / second packaging material 15 (water vapor barrier film) / packaging material 14 (aluminum film) / outside of the packaging body", and the method of arranging the packaging body in the order of "film roll 13 / protection pad 16 / packaging material 14 (aluminum film) / second packaging material 15 (water vapor barrier film) / outside of the packaging body".

[0130] In addition, in the aforementioned film roll package, in order to adjust the internal humidity of the package, a desiccant and a hygroscopic agent can be additionally sealed. As the aforementioned desiccant and hygroscopic agent, there can be listed: a hygroscopic layer formed by dispersing, impregnating, coating and drying desiccant or hygroscopic agent such as calcium chloride, silica gel, molecular sieve, sugar, especially sugar with high osmotic pressure, and water-absorbing resin on natural cellulose, synthetic cellulose, glass cloth, non-woven fabric and other formable materials. In addition, there can be listed: a sandwich-shaped sandwich formed by sandwiching these hygroscopic agents or water-absorbing materials with these formable materials, polyester films, polyethylene films, polypropylene films, Teflon (registered trademark) films and other thermoplastic resin films. As commercially available sheet desiccant, there can be exemplified: "ID Sheet" made by IDCO., LTD., "Arrow Sheet", "Zeo Sheet" made by Shinagawa Chemical Co., Ltd., "Hi Sheet Dry" made by Hi Sheet Industrial Co., Ltd., etc.

[0131] Moreover, there is no particular restriction on the manufacturing method of the aforementioned film roll packaging body, and it can be manufactured by any manufacturing method. However, from the perspective of being able to efficiently and smoothly package the film roll 13, a method having the following steps can be adopted: a step of installing protective pads 16 at both ends of the film roll 13, a step of packaging the film roll 13 with the protective pads 16 installed with a packaging material 14 (aluminum film) and / or a second packaging material 15 (water vapor barrier film), and preferably a step of further installing a second protective pad at both ends of the aforementioned packaged film roll 13.

[0132] The film roll packaging body obtained by such operation can fully prevent the breakage of the packaging materials 14 and 15 near the end surface of the film roll 13 and the damage of the film roll 13 during storage and transportation, and can still suppress the damage of the film roll 13 even when the film roll 13 is used in a clean room.

[0133] The storage conditions when storing the film roll 13 in the form of a film roll package are not particularly limited, but it is ideal to avoid extreme high temperature, low temperature, low humidity, and high humidity conditions. Specifically, the storage temperature is preferably in the range of -20 to 50° C., more preferably in the range of -10 to 40° C., and further preferably in the range of -5 to 30° C. In addition, the storage humidity is preferably 90% RH or less, and more preferably 45 to 80% RH.

[0134] The storage time when the film roll package is stored is not particularly limited, and is, for example, preferably within a range of 1 day to 1 year, and more preferably within a range of 2 days to 6 months.

[0135] Thus, according to the film roll packaging body of the present invention, it is possible to fully prevent damage to the film roll during storage or transportation, and damage to the packaging material near the end surface of the film roll. Moreover, even when the film roll is used in a clean room, damage to the film roll can be suppressed, and dust and dirt attached to the film roll can be suppressed, and further, shavings generated by the packaging material can be suppressed. Therefore, the present invention includes the aforementioned storage or transportation method of the film roll 13 in which the film roll is stored or transported in the form of the packaging body of the present invention.

[0136] Furthermore, the film roll stored or transported in the form of the film roll package of the present invention can reduce breakage when the polyvinyl alcohol film of the film roll is uniaxially stretched or suppress the generation and adhesion of dust, and can therefore be preferably used as a polarizing film or polarizing plate for providing excellent optical properties.

[0137] As described above, the polyvinyl alcohol-based film in the film roll package of the present invention is effectively used as a raw film for optical purposes, particularly for polarizing films. Therefore, a method for producing a polarizing film will be described below.

[0138] As a method for producing a polarizing film, there are listed: a method of stretching the polyvinyl alcohol film and immersing it in a solution of iodine or a dichroic dye to dye it, a method of stretching and dyeing it at the same time, a method of dyeing it with iodine or a dichroic dye and then treating it with a boron compound. In addition, there is also a method of stretching it in a solution of a boron compound after dyeing, etc., which can be appropriately selected and used.

[0139] The film thickness of the polyvinyl alcohol film used in the polarizing film is preferably 10 to 100 μm, more preferably 10 to 70 μm, further preferably 15 to 50 μm, and particularly preferably 15 to 40 μm. By setting the film thickness within the above range, a decrease in film forming accuracy can be suppressed.

[0140] When the polyvinyl alcohol film (unstretched film) is stretched, dyed, and treated with a boron compound, the stretching, dyeing, and boron compound treatment may be performed separately or simultaneously, but it is ideal to perform uniaxial stretching in at least one of the dyeing and boron compound treatment steps.

[0141] It is ideal to stretch 3 to 10 times, preferably 3.5 to 6 times in a uniaxial direction. At this time, it is also OK to stretch a little in the direction perpendicular to the above (to prevent the shrinkage in the width direction or stretching above it). It is ideal to select the temperature condition of 40 to 170°C during stretching. Furthermore, the stretching ratio can be finally set in the above range, and the stretching operation is not only one stage, but can be implemented in any stage of the manufacturing process.

[0142] The film is dyed by contacting a liquid containing iodine or a dichroic dye with the film. Usually, an iodine-potassium iodide aqueous solution is used, and the concentration of iodine is 0.1 to 20 g / L, the concentration of potassium iodide is 10 to 70 g / L, and the mass ratio of potassium iodide to iodine is 10 to 100. It is practical to dye for about 30 to 500 seconds. The temperature of the treatment bath is preferably 5 to 60°C. In addition to the aqueous solvent, a small amount of an organic solvent compatible with water may also be contained. As a contact method, any method such as dipping, coating, spraying, etc. can be applied.

[0143] The dyed film is then treated with a boron compound. Boric acid and borax are practical as boron compounds. The boron compound is used in the form of an aqueous solution or a water-organic solvent mixture at a concentration of about 0.3 to 2 mol / L. It is practically ideal to have a small amount of potassium iodide coexist in the liquid. The treatment method is preferably an immersion method, but of course a coating method or a spraying method can also be implemented. The temperature during the treatment is preferably about 40 to 70°C, and the treatment time is preferably about 2 to 20 minutes. In addition, a stretching operation can be performed during the treatment as needed.

[0144] The polarizing film thus obtained can also be laminated and bonded to one or both sides of an optically isotropic polymer film or sheet as a protective film. Examples of the protective film include films or sheets of triacetyl cellulose, diacetyl cellulose, polycarbonate, polymethyl methacrylate, polystyrene, polyether sulfone, polyarylene ester, poly-4-methylpentene, polyphenylene oxide, and the like.

[0145] In order to reduce the thickness of the polarizing film, a curable resin such as a urethane resin, an acrylic resin, or a urea resin may be coated or laminated on one or both sides of the polarizing film instead of the protective film.

[0146] For the polarizing film (or the one having a protective film or curable resin laminated on at least one side thereof), a transparent pressure-sensitive adhesive layer is sometimes formed on one side of the surface thereof by a commonly known method as needed for practical use. As the aforementioned pressure-sensitive adhesive layer, a copolymer of acrylate, such as butyl acrylate, ethyl acrylate, methyl acrylate, 2-ethylhexyl acrylate, etc. and α-monoolefin carboxylic acid, such as acrylic acid, maleic acid, itaconic acid, methacrylic acid, crotonic acid, etc. (also including a vinyl monomer such as acrylonitrile, vinyl acetate, styrene, etc.) as the main body is particularly preferred because it does not hinder the polarizing properties of the polarizing film, but it is not limited to this. As long as it is a transparent pressure-sensitive adhesive, it can be used, for example, it can also be a polyvinyl ether-based substance, a rubber-based substance, etc.

[0147] In addition, various functional layers may be further provided on one side (the side not provided with the pressure-sensitive adhesive) of the polarizing plate (provided with the pressure-sensitive adhesive), and examples of the functional layers include: an anti-glare layer, a hard coating layer, an anti-reflection layer, a semi-reflection layer, a reflection layer, a light storage layer, a diffusion layer, an electroluminescent layer, a viewing angle widening layer, a brightness enhancement layer, and the like. Furthermore, various layers of two or more may be combined, and examples thereof include: a combination of an anti-glare layer and an anti-reflection layer, a light storage layer and a reflection layer, a light storage layer and a semi-reflection layer, a light storage layer and a light diffusion layer, a light storage layer and an electroluminescent layer, a semi-reflection layer and an electroluminescent layer, and the like. However, the present invention is not limited to these.

[0148] Example

[0149] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist of the present invention is exceeded.

[0150] It should be noted that "%" in the examples refers to the mass basis.

[0151] <Example 1>

[0152] A foamed member (made of polyethylene) with a thickness of 10 mm, a foaming ratio of 10 times (independent bubbles), and a 25% compressive stress of 35 kPa was prepared as a protective pad. Then, an aluminum film (stretched polypropylene film / polyethylene film / aluminum foil (thickness 7 μm) / polyethylene film) was stacked on the protective pad as a packaging material to prepare a test body.

[0153] <Example 2>

[0154] A test body was prepared in the same manner as in Example 1 except that the thickness of the foam member used as the protection pad was set to 20 mm.

[0155] <Example 3>

[0156] The same packaging material as in Example 1 was stacked on the same protective mat as in Example 1, and the same protective mat as in Example 1 was stacked on top of the packaging material to prepare a test piece.

[0157] <Comparative Example 1>

[0158] As the protective pad, a foam material (made of polyethylene) having a thickness of 4 mm and a 25% compressive stress of 36 kPa was used. A test body was prepared in the same manner as in Example 1 except for the above.

[0159] <Comparative Example 2>

[0160] A test piece was prepared by using only an aluminum film as a packaging material without using a protective mat.

[0161] <Comparative Example 3>

[0162] A foam material (made of polypropylene) having a thickness of 4 mm and a 25% compressive stress of 36 kPa was used as a protective pad. A test body was prepared in the same manner as in Example 3 except for the above.

[0163] The test bodies of the above-mentioned examples and comparative examples were subjected to impact using a DuPont impact tester according to the following method to evaluate the damage of the packaging material. The results are shown in Table 1 described below. The structures of the test bodies are shown in Table 1 together.

[0164] <Evaluation of damage to packaging materials>

[0165] A DuPont impact tester (device reference: JIS K5600 5-3 (6): 1999) was used, and the test conditions were set to impact die radius: 1 / 8 inch, support platform radius: 1 / 8 inch, weight: 300g, drop height: 30cm. The test body was installed and tested in such a way that the packaging material was on top. The evaluation was carried out 5 times to confirm the damage state of the packaging material. The evaluation criteria were set as follows.

[0166] ○(Good): No cracks

[0167] ×(bad): through-break

[0168] [Table 1]

[0169]

[0170] <Example 4>

[0171] (Production of polyvinyl alcohol film)

[0172] In a 5,000 L dissolving kettle, 1,000 kg of a polyvinyl alcohol-based resin having a weight average molecular weight of 123,000 and a saponification degree of 99.8 mol%, 3,000 kg of water, 115 kg of glycerin as a plasticizer, and 0.25 kg of sodium dodecyl sulfate as a surfactant were added, and the mixture was heated to 150° C. and pressure dissolved while stirring to obtain a polyvinyl alcohol-based resin aqueous solution adjusted to a resin concentration of 29%.

[0173] Next, the polyvinyl alcohol resin aqueous solution was supplied to a twin-screw extruder with vent holes and degassed, and then the aqueous solution temperature was set to 95°C, and discharged from a T-slit die outlet and cast onto a casting die rotating at 12 m / min to form a film. Next, the surface and back of the film were alternately contacted with 15 hot rollers in total for drying, and hot air at 95°C was blown from both sides of the film for heat treatment.

[0174] (Film roll production)

[0175] The obtained film was wound around a cylindrical aluminum core tube of 340 cm in length and 6 inches in diameter to obtain a film roll (film thickness 45 μm, width 3 m, length 5 km). At this time, the end surface and outer peripheral surface of the film roll were visually observed, and no dust, shavings, etc. were observed.

[0176] (Production of protective pads)

[0177] A foamed component (made of polyethylene) with a thickness of 10 mm, a foaming ratio of 10 times (independent bubbles), and a 25% compressive stress of 35 kPa is laminated to a non-foamed resin sheet (made of polyethylene) with a thickness of 15 μm (the surface roughness Ra of the non-foamed resin sheet after lamination is 0.6 μm, the surface roughness Ry is 2.1 μm, and the surface roughness Rz is 2.0 μm), and cut according to the shape of the roller end surface, thereby preparing two protective pads with non-foamed resin layers on both sides.

[0178] (Production of film roll packaging)

[0179] After the two protective pads were installed with their non-foamed resin layers facing the end faces of the film roll, the outer periphery of the film roll was covered with a water vapor barrier film (polyethylene, thickness 30 μm, moisture permeability 7 g / m 2 Then, the excess portion of the film roll of the water vapor barrier film in the width direction is fixed to the core tube with a rubber band.

[0180] Next, an aluminum film (oriented polypropylene film / polyethylene film / aluminum foil (thickness 7 μm) / polyethylene film) as a packaging material is double-wound from above the film roll wrapped with the water vapor barrier film, and the excess portion of the aluminum film in the width direction of the film roll is fixed to the core tube with an adhesive tape to complete the packaging (see Figure 1 ).

[0181] Then, the protruding portion of the core tube is placed on the bracket so that the film roll is not grounded but floats in the air. It should be noted that the packaging form is equivalent to the form of the test body of the above-mentioned Example 1 in terms of installing a set of protective pads.

[0182] The obtained film roll package was stored for 7 days and then transported by land and sea for 10 days according to a prescribed route. After transportation, the appearance of the aluminum film used as the packaging material was checked, and no damage was found. Next, the packaging material of the film roll was removed and the appearance of the polyvinyl alcohol film was visually checked, and almost no dust, debris, etc. were found to be attached to the end surface and outer peripheral surface of the film roll.

[0183] <Example 5>

[0184] Two sets (a total of four sets) of the same protective pads as in Example 4 were prepared, with two pads forming one set. Then, after one set of protective pads was installed with the non-foamed resin layer side of each set facing the end face of the film roll, the outer periphery of the film roll was covered with a water vapor barrier film (polyethylene, thickness 30 μm, moisture permeability 7 g / m 2 Then, the excess portion of the film roll of the water vapor barrier film in the width direction is fixed to the core tube with a rubber band.

[0185] Next, an aluminum film (stretched polypropylene film / polyethylene film / aluminum foil (thickness 7 μm) / polyethylene film) as a packaging material is double-wound from above the film roll wrapped with the aforementioned water vapor barrier film, and another set of protective pads is installed from above the aforementioned aluminum film with the non-foamed resin layer side of each facing the end side of the film roll. Then, the excess portion of the aforementioned aluminum film in the width direction of the film roll is fixed to the core tube with an adhesive tape to complete the packaging.

[0186] Next, the protruding portion of the core tube is placed on a bracket so that the film roll is not grounded but floats in the air. It should be noted that the packaging form is equivalent to the test body of Example 3 in that two sets of protective pads are used on the inside and outside of the packaging material.

[0187] The obtained film roll package was stored for 7 days and then transported by land and sea for 10 days according to the specified route. After transportation, the appearance of the aluminum film used as the packaging material was checked, and no damage was found. Then, the packaging material of the film roll was removed and the appearance of the polyvinyl alcohol film was visually checked. As a result, almost no dust, debris, etc. were found to be attached to the end surface and outer peripheral surface of the film roll.

[0188] <Research>

[0189] According to the above results, it is confirmed that the film roll package specified in the present invention can suppress the damage of the packaging material during storage and transportation, and suppress the adhesion of dust, cuttings, etc. to the polyvinyl alcohol film. Therefore, the polyvinyl alcohol film can be used in a higher level clean room, and the breakage of the polyvinyl alcohol film when uniaxially stretched can be reduced. In addition, it is known that the reduction in optical properties can be suppressed when the polyvinyl alcohol film is processed into a polarizing film or a polarizing plate.

[0190] The above embodiments show specific aspects of the present invention, but the above embodiments are merely illustrative and are not to be construed as limiting. Various modifications that are obvious to those skilled in the art are expected to be included in the scope of the present invention.

[0191] Industrial Applicability

[0192] The film roll packaging body of the present invention fully prevents the packaging material of the film roll from being damaged during storage and transportation, and fully prevents damage and contamination of the film roll. Even if the film roll is used in a clean room, damage and contamination of the film roll can be suppressed. Therefore, the quality of the polyvinyl alcohol film wound in the form of a film roll will not be damaged, and it is useful as a technology for maintaining it well.

[0193] Description of Reference Numerals

[0194] 11: Polyvinyl alcohol film

[0195] 12: Core tube

[0196] 13: Film roll

[0197] 14: Packaging materials

[0198] 16: Protective pad

Claims

1. A film roll packaging body, comprising: Film rolls made by winding polyvinyl alcohol-based films around core tubes, Packaging material for packaging the film roll, and Protective pads are arranged on both ends of the film roll. The packaging material is at least composed of a film containing an aluminum raw material, The protective pad is composed of a foamed member in which the value of H in the following formula (1) is 0.18 or more, T / K=H...(1) T: thickness of the foamed member, the unit of thickness is mm, K: 25% compressive stress of the foamed member, the unit of compressive stress is kPa.

2. The film roll package according to claim 1, wherein: The film containing the aluminum raw material is a laminated film of a polyolefin film and an aluminum foil.

3. The film roll package according to claim 1 or 2, wherein: The film containing an aluminum raw material is a laminated film having at least a laminated structure of polyethylene film / aluminum foil / polyethylene film. 4 . The film roll package according to claim 1 , further comprising a second packaging material composed of a water vapor barrier film.

5. The film roll package according to claim 1 or 2, wherein: The foam member constituting the protection pad is made of foamed polyethylene resin.

6. The film roll package according to claim 1 or 2, wherein: The foam member constituting the protection pad has a thickness of 3 mm or more.

7. The film roll package according to claim 1 or 2, wherein: The 25% compressive stress of the foam member constituting the protection pad is less than 50 kPa.

8. A method for manufacturing a film roll packaging body, which is the method for manufacturing a film roll packaging body according to claim 1 or 2, comprising: The process of installing protective pads on both ends of the film roll, and A step of packaging the film roll to which the protective mat is attached using a packaging material made of a film containing an aluminum raw material.

9. A method for storing or transporting a film roll, which stores or transports the film roll in the form of the film roll packaging body according to claim 1 or 2.

Images