CN108121027A - The manufacturing method of polarizability stacked film and the manufacturing method of polarization plates with protective film - Google Patents

Abstract

A method for producing a polarizing laminated film with a protective film and a method for producing a polarizing plate. Provided is a method for producing a polarizing laminated film with a protective film that can provide a polarizing plate with suppressed image distortion when used as a production intermediate of a polarizing plate. Provided is a method for producing a polarizing laminated film with a protective film, the production method comprising: forming a polyvinyl alcohol-based resin layer on at least one surface of a base film to obtain a laminated film; stretching the laminated film to obtain a laminated film; The process of stretching the laminated film, the process of dyeing the polyvinyl alcohol-based resin layer of the stretched laminated film with a dichroic dye to form a polarizer layer, thereby obtaining a polarizing laminated film, and the polarizing plate in the polarizing laminated film In the step of laminating a protective film on the layer-side surface to obtain a polarizing laminated film with a protective film, the arithmetic mean roughness of the polarizer layer-side surface of the protective film is 0.150 μm or less.

Description

Manufacturing method of polarizing laminated film with protective film and manufacturing method of polarizing plate

technical field

The present invention relates to a method of manufacturing a polarizing laminated film with a protective film and a method of manufacturing a polarizing plate. Moreover, this invention relates to the polarizing laminated film with a protective film, and the polarizing laminated film roll with a protective film.

Background technique

Polarizing plates are widely used in image display devices represented by liquid crystal display devices and the like. A polarizing plate generally has a configuration in which a thermoplastic resin film such as a protective film is bonded to one or both sides of a polarizer layer made of a polyvinyl alcohol-based resin. In recent years, with the spread of image display devices in mobile devices, thin TVs, and the like, there has been an increasing demand for thinner polarizers and even polarizer layers.

As a method of manufacturing a polarizing plate having a polarizer layer of a film, a method is known in which a coating solution containing a polyvinyl alcohol-based resin is applied to a base film to form a polyvinyl alcohol-based resin layer, and the formed laminate is laminated. After the film is stretched, dyeing treatment in which a dichroic dye is adsorbed on the polyvinyl alcohol-based resin layer is carried out to manufacture a polarizing laminated film in which a polarizer layer is formed on the base film, and then, the After bonding thermoplastic resin films such as a protective film to the surface opposite to the base film using an adhesive, the base film is peeled and removed if necessary (for example, Patent Document 1).

According to the above-mentioned method, since the polyvinyl alcohol-based resin layer is formed by coating, it is easier to thin the polyvinyl alcohol-based resin layer than to thin a single-layer (monomer) film containing the polyvinyl alcohol-based resin, so polarizing Thinning of the sheet is also easy. In addition, since the polyvinyl alcohol-based resin layer and the polarizing plate layer of the film are always supported by a certain film during the production process, the handleability of the film during the production process is also excellent.

Active energy ray-curable adhesives such as water-based adhesives and ultraviolet-curable adhesives are known as the above-mentioned adhesives for laminating thermoplastic resin films, and are used for laminating thermoplastic resin films with low moisture permeability. In some cases, it is difficult to volatilize and remove moisture from the adhesive layer after laminating the thermoplastic resin film, so active energy ray-curable adhesives are often used (for example, Patent Documents 2 to 5).

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2000-338329

Patent Document 2: Japanese Unexamined Patent Publication No. 2013-205741

Patent Document 3: Japanese Patent Laid-Open No. 2012-203205

Patent Document 4: Japanese Patent Laid-Open No. 2012-203108

Patent Document 5: Japanese Patent Laid-Open No. 2004-245925

Contents of the invention

[Problem to be solved by the invention]

When a thermoplastic resin film is attached to the polarizer layer using an active energy ray-curable adhesive, and the obtained polarizing plate is observed from the side of the thermoplastic resin film under a fluorescent lamp, an image of a fluorescent lamp reflected on the surface of the thermoplastic resin film may sometimes be seen. deformed. Hereinafter, in this specification, such a phenomenon in which a reflected image is deformed is referred to as "image distortion". This image deformation is not only undesirable in the appearance of the polarizing plate, but also may cause adverse effects such as display deformation on the visibility (visibility) of the display device when the polarizing plate is incorporated into the image display device. .

The object of the present invention is to provide an optical laminated body (polarizing laminated film with a protective film) and a production method thereof, which can provide a polarizing plate in which the above-mentioned image distortion is suppressed when the optical laminated body is used as a production intermediate of a polarizing plate . Another object of the present invention is to provide a polarizing plate in which the above-mentioned image distortion is suppressed, and a method for producing the same.

[means used to solve a problem]

The present invention provides a method for producing a polarizing laminated film with a protective film, a method for producing a polarizing plate, a polarizing laminated film with a protective film, and a roll of a polarizing laminated film with a protective film as described below.

[1] A method for producing a polarizing laminated film with a protective film, comprising: forming a polyvinyl alcohol-based resin layer on at least one surface of a base film to obtain a laminated film; stretching the laminated film And the process of obtaining a stretched laminated film,

A step of obtaining a polarizing laminated film by dyeing the polyvinyl alcohol-based resin layer of the stretched laminated film with a dichroic dye to form a polarizer layer, and

The process of laminating a protective film on the surface of the above-mentioned polarizing laminated film on the side of the polarizer layer to obtain a polarizing laminated film with a protective film,

The arithmetic average roughness of the surface of the polarizer layer side of the said protective film is 0.150 micrometer or less.

[2] The production method according to [1], wherein

The said protective film is laminated|stacked in contact with the surface of the said polarizer layer.

[3] The manufacturing method according to [1] or [2], further comprising:

A step of winding up the polarizing laminated film with a protective film to obtain a polarizing laminated film with a protective film roll.

[4] A manufacturing method of a polarizing plate, the manufacturing method comprising:

A step of obtaining a polarizing laminated film with a protective film by the production method described in [1] or [2];

A step of peeling off the above-mentioned protective film from the above-mentioned polarizing laminated film with a protective film;

a step of laminating a first thermoplastic resin film via a layer of an active energy ray-curable adhesive on the surface of the polarizing laminate film exposed by the step of peeling off the protective film on the side of the polarizer layer; and

A step of curing the layer of the active energy ray-curable adhesive.

[5] The production method according to [4], wherein

Between the step of obtaining the polarizing laminated film with a protective film and the step of peeling off the protective film, further comprising: winding the polarizing laminated film with a protective film to obtain a polarizing laminated film roll with a protective film material process,

In the step of peeling the protective film, the protective film is peeled from the polarizing laminated film with a protective film unwound from the polarizing laminated film with a protective film roll.

[6] The production method according to [4] or [5], wherein

After the step of hardening the layer of the active energy ray-curable adhesive, a step of peeling the base film is further included.

[7] A polarizing laminated film with a protective film, comprising: a substrate film, a polarizer layer comprising a polyvinyl alcohol-based resin, and a protective film in this order,

The arithmetic average roughness of the surface of the polarizer layer side of the said protective film is 0.150 micrometer or less.

[8] The polarizing laminated film with a protective film according to [7], wherein the protective film is in contact with the surface of the polarizer layer.

[9] A polarizing laminated film roll with a protective film, which is a rolled product of the polarizing laminated film with a protective film according to [7] or [8].

[Effect of the invention]

There can be provided an optical laminate (polarizing laminated film with a protective film), a roll of the optical laminate, and a method for producing the same, which can provide a suppressed image distortion when used as a production intermediate of a polarizing plate. polarizing plate. In addition, it is possible to provide a polarizing plate in which image deformation is suppressed and a method for manufacturing the same.

Description of drawings

FIG. 1 is a flowchart showing a method of manufacturing a polarizing laminated film with a protective film according to one embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view showing an example of a layer configuration of a laminated film obtained in a resin layer forming step.

Fig. 3 is a schematic cross-sectional view showing an example of the layer constitution of a stretched laminated film obtained in a stretching step.

Fig. 4 is a schematic cross-sectional view showing an example of the layer configuration of a polarizing laminated film obtained in a dyeing step.

5 is a schematic cross-sectional view showing an example of the layer configuration of a polarizing laminated film with a protective film obtained in a protective film lamination step.

FIG. 6 is a flowchart showing a method of manufacturing a polarizing plate according to an embodiment of the present invention.

FIG. 7 is a schematic cross-sectional view showing an example of a layer configuration of a film obtained in a protective film peeling step.

8 is a schematic cross-sectional view showing an example of the layer configuration of the first polarizing plate obtained through the first bonding step and the curing step.

9 is a schematic cross-sectional view showing an example of the layer configuration of a second polarizing plate obtained in a base film peeling step.

FIG. 10 is a schematic cross-sectional view showing an example of the layer configuration of a third polarizing plate.

Detailed ways

Hereinafter, embodiments will be shown and the present invention will be described in detail.

<Manufacturing method of polarizing laminated film with protective film>

FIG. 1 is a flowchart showing a method of manufacturing a polarizing laminated film with a protective film according to one embodiment of the present invention. As shown in FIG. 1, the manufacturing method of the polarizing laminated film with a protective film related to one embodiment of the present invention includes the following steps:

Resin layer forming step S10, forming a polyvinyl alcohol-based resin layer on at least one surface of the base film to obtain a laminated film;

Stretching step S20, stretching the laminated film to obtain a stretched laminated film;

Dyeing step S30, dyeing the polyvinyl alcohol-based resin layer of the stretched laminated film with a dichroic dye to form a polarizer layer, thereby obtaining a polarizing laminated film;

In the protective film lamination step S40, a protective film is laminated on the surface of the polarizing laminated film on the polarizer layer side to obtain a polarizing laminated film with a protective film.

The manufacturing method of the polarizing laminated film with a protective film may further include after the protective film laminating step S40: a winding step, wherein the polarizing laminated film with a protective film is wound up to obtain a polarizing laminated film roll with a protective film . The polarizing laminated film with a protective film and the roll of the polarizing laminated film with a protective film can be used as a production intermediate for producing a polarizing plate as will be described later.

In this specification, "polarizing laminated film" means a base film and a polarizer layer laminated on the base film, and does not include a protective film laminated (bonded) on the polarizer layer via an adhesive layer. Films such as thermoplastic resin films. What laminated|stacked the protective film on the polarizer layer side surface of a polarizing laminated film is called "the polarizing laminated film with a protective film" in this specification. In addition, in this specification, a "polarizing plate" refers to a film containing a polarizer layer and a thermoplastic resin film such as a protective film laminated (bonded) on at least one surface of the polarizer layer via an adhesive layer. A polarizing plate may also contain the above-mentioned base film. In addition, the polarizing plate may also include: a polarizer layer; a first thermoplastic resin film such as a protective film laminated (bonded) through an adhesive layer on at least one surface of the polarizer layer; A second thermoplastic resin film such as a protective film laminated (bonded) with an agent layer or an adhesive layer.

A thermoplastic resin film such as a protective film laminated (bonded) on a polarizer layer via an adhesive layer is usually an optical film. The optical film refers to a film that is a member or a part thereof incorporated in an optical device such as a display device. The base film is, for example, a film made of a thermoplastic resin, and is usually not incorporated into optical devices such as display devices, but is usually peeled and removed before the assembly. Therefore, it is preferable that a base film can peel from a polarizer layer. However, it is not excluded that the substrate film can be used as an optical film.

Hereinafter, each of the above steps will be described with reference to the drawings.

[1] Resin layer forming step S10

Referring to FIG. 2 , this step is a step of forming a polyvinyl alcohol-based resin layer 6 on at least one surface of a base film 30 to obtain a laminated film 100 . The polyvinyl alcohol-based resin layer 6 is stretched and dyed to become the polarizer layer 5 ( FIG. 4 ). The polyvinyl alcohol-based resin layer 6 can be formed by applying a coating solution containing a polyvinyl alcohol-based resin to one or both surfaces of the base film 30 and drying it. Such a method of forming the polyvinyl alcohol-based resin layer 6 by coating is advantageous, for example, from the viewpoint that it is easy to obtain the polarizer layer 5 of a thin film. In the resin layer forming step S10 , for example, the base film 30 is continuously unwound from a film roll that is a roll of the elongated base film 30 and conveyed, and at the same time, the resin layer forming step is continuously performed. S10. The film conveyance can be performed using guide rollers or the like.

(substrate film)

The base film 30 may be made of a thermoplastic resin, and among them, it is preferably made of a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, stretchability, and the like. Specific examples of such thermoplastic resins include polyolefin-based resins such as chain polyolefin-based resins and cyclic polyolefin-based resins (norbornene-based resins, etc.); polyester-based resins; (meth)acrylic resins Cellulose ester resins such as triacetyl cellulose and diacetyl cellulose; polycarbonate resins; polyvinyl alcohol resins; polyvinyl acetate resins; polyarylate resins; polystyrene resins; Polyethersulfone-based resins; polysulfone-based resins; polyamide-based resins; polyimide-based resins; and their mixtures, copolymers, and the like.

In this specification, "(meth)acrylic" means at least one selected from acrylic and methacrylic. The same applies when "(meth)acryloyl" and the like are described.

The base film 30 may be a single-layer structure composed of one resin layer containing one or more thermoplastic resins, or may be formed by laminating resin layers containing one or two or more thermoplastic resins. multi-layer structure. The base film 30 is preferably composed of a resin that is stretched at a stretching temperature suitable for stretching the polyvinyl alcohol-based resin layer 6 when stretching the laminated film 100 in the stretching step S20 described later. Can be stretched.

Examples of the chain polyolefin-based resin include homopolymers of chain olefins such as polyethylene resins and polypropylene resins, and copolymers containing two or more types of chain olefins. The base film 30 made of a chain polyolefin resin is preferable because it is easy to stretch stably at a high ratio. Among them, the base film 30 more preferably contains: polypropylene-based resin (polypropylene resin as a propylene homopolymer, copolymer mainly composed of propylene), polyethylene-based resin (polyethylene resin as an ethylene homopolymer, Ethylene-based copolymers), etc.

As an example of the thermoplastic resin which comprises the base film 30, the copolymer mainly containing propylene which is used preferably can be a copolymer of propylene and other monomers which can be copolymerized with it.

Examples of monomers that can be copolymerized with propylene include ethylene and α-olefins. The α-olefin is preferably an α-olefin having 4 or more carbon atoms, more preferably an α-olefin having 4 to 10 carbon atoms. Specific examples of α-olefins having a carbon number of 4 to 10 include straight chains such as 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, and 1-decene. Monoolefins; branched monoolefins such as 3-methyl-1-butene, 3-methyl-1-pentene, and 4-methyl-1-pentene; vinylcyclohexane, etc. The copolymer of propylene and other monomers that can be copolymerized therewith may be a random copolymer or a block copolymer.

The content of the above-mentioned other monomers in the copolymer is, for example, 0.1 to 20% by weight, preferably 0.5 to 10% by weight. The content of other monomers in the copolymer can be determined by performing infrared (IR) spectrum measurement according to the method described on page 616 of "Polymer Analysis Handbook" (1995, published by Kinokuniya Shoten).

Among the above, the polypropylene-based resin is preferably a propylene homopolymer, a propylene-ethylene random copolymer, a propylene-1-butene random copolymer, or a propylene-ethylene-1-butene random copolymer.

The stereoregularity of the polypropylene-based resin is preferably substantially isotactic or syndiotactic. The base film 30 composed of a polypropylene-based resin having substantially isotactic or syndiotactic stereoregularity has relatively good handleability and is excellent in mechanical strength in a high-temperature environment.

Cyclic polyolefin-based resins are a general term for resins polymerized using cyclic olefins as polymerized units. Resins described in Publication No. 1, etc. Specific examples of cyclic polyolefin-based resins include: ring-opening (co)polymers of cyclic olefins; addition polymers of cyclic olefins; chain olefins such as cyclic olefins and ethylene and propylene. Copolymers (typically, random copolymers); and graft polymers obtained by modifying them with unsaturated carboxylic acids and their derivatives; and their hydrogenated products. Among these, norbornene-based resins using norbornene-based monomers such as norbornene and polycyclic norbornene-based monomers as cyclic olefins are preferably used.

The polyester-based resin is a resin having an ester bond other than the cellulose ester-based resin described below, and generally contains a polycondensate of a polycarboxylic acid or its derivative and a polyhydric alcohol. As the polyvalent carboxylic acid or its derivative, divalent dicarboxylic acid or its derivative can be used, and examples thereof include terephthalic acid, isophthalic acid, dimethyl terephthalate, and dimethyl naphthalene dicarboxylate. As the polyhydric alcohol, divalent diols can be used, and examples thereof include ethylene glycol, propylene glycol, butanediol, neopentyl glycol, and cyclohexanedimethanol.

Typical examples of polyester-based resins include polyethylene terephthalate, which is a polycondensate of terephthalic acid and ethylene glycol. Polyethylene terephthalate is a crystalline resin, and processing such as stretching can be easily performed in the state before crystallization treatment. If necessary, crystallization treatment may be performed during stretching or by heat treatment after stretching. In addition, it is also preferable to use a copolyester in which crystallinity is lowered (or made amorphous) by further copolymerizing other types of monomers in the framework of terephthalate. Examples of such resins include, for example, those obtained by copolymerizing cyclohexanedimethanol and isophthalic acid. Since these resins are also excellent in stretchability, they can be suitably used.

If specific examples of polyester-based resins other than polyethylene terephthalate and its copolymers are given, such as polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, ester, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexanedimethyl terephthalate, polycyclohexanedimethylnaphthalate.

A (meth)acrylic resin is resin which has a compound which has a (meth)acryloyl group as a main constituent monomer. Specific examples of (meth)acrylic resins include, for example: poly(meth)acrylates such as polymethyl methacrylate; methyl methacrylate-(meth)acrylic acid copolymer; methyl methacrylate- (Meth)acrylate copolymer; methyl methacrylate-acrylate-(meth)acrylic acid copolymer; (meth)methyl acrylate-styrene copolymer (MS resin, etc.); methyl methacrylate and Copolymers of compounds having an alicyclic hydrocarbon group (for example, methyl methacrylate-cyclohexyl methacrylate copolymer, methyl methacrylate-norbornyl (meth)acrylate copolymer, etc.). It is preferable to use a poly(meth)acrylate C _1-6 alkyl ester as a main component polymer such as poly(methyl)acrylate, more preferably to use methyl methacrylate as a main component (50 to 100 % by weight, preferably 70 to 100% by weight) of methyl methacrylate resin.

Cellulose ester-based resins are esters of cellulose and fatty acids. Specific examples of cellulose ester-based resins include triacetyl cellulose, diacetyl cellulose, cellulose tripropionate, and cellulose dipropionate. In addition, those copolymers and those obtained by modifying a part of the hydroxyl groups with other substituents are also mentioned. Among them, cellulose triacetyl ester (triacetyl cellulose) is particularly preferable.

Polycarbonate-based resins are engineering plastics composed of polymers in which monomer units are bonded via carbonate groups, and are resins having high impact resistance, heat resistance, flame retardancy, and transparency. The polycarbonate-based resin constituting the base film 30 may be a resin called a modified polycarbonate whose main chain is modified to lower the photoelastic coefficient, or a copolycarbonate with improved wavelength dependence.

Among the above, one of the thermoplastic resins preferably used is a polypropylene-based resin from the viewpoint of stretchability, heat resistance, and the like.

Arbitrary appropriate additives may be contained in the base film 30 other than the said thermoplastic resin. Examples of additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, release agents, anti-coloring agents, flame retardants, nucleating agents, antistatic agents, pigments, and colorants. The content of the thermoplastic resin in the base film 30 is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, still more preferably 60 to 98% by weight, particularly preferably 70 to 97% by weight.

The thickness of the base film 30 is usually 1 to 500 μm, preferably 1 to 300 μm, more preferably 5 to 200 μm, and even more preferably 5 to 150 μm from the viewpoint of strength and handleability.

(Formation of polyvinyl alcohol-based resin layer)

The coating liquid applied to the base film 30 is preferably a polyvinyl alcohol-based resin solution obtained by dissolving powder of a polyvinyl alcohol-based resin in a good solvent (for example, water). The coating liquid may contain additives such as plasticizers and surfactants as necessary. As the polyvinyl alcohol-based resin, a saponified polyvinyl acetate-based resin can be used. Examples of polyvinyl acetate-based resins include polyvinyl acetate that is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers that can be copolymerized therewith. Examples of other monomers that can be copolymerized with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having ammonium groups.

The degree of saponification of the polyvinyl alcohol-based resin may be in the range of 80.0 to 100.0 mol%, preferably in the range of 90.0 to 99.5 mol%, more preferably in the range of 94.0 to 99.0 mol%. When the degree of saponification is less than 80.0 mol %, the water resistance and heat-and-moisture resistance of the polarizing laminated film, the polarizing laminated film with a protective film, and the polarizing plate may decrease. When a polyvinyl alcohol-based resin having a degree of saponification of more than 99.5 mol % is used, the dyeing speed of the dichroic dye may be slowed down, which may lower productivity, and a polarizer layer having sufficient polarizing performance may not be obtained.

Regarding the degree of saponification, the ratio of the acetic acid group (acetoxy group: -OCOCH ₃ ) contained in the polyvinyl acetate-based resin, which is a raw material of the polyvinyl alcohol-based resin, into a hydroxyl group through the saponification process is expressed as a unit ratio (molar %), and defined by the following formula,

Degree of saponification (mol %)=100×(number of hydroxyl groups)÷(number of hydroxyl groups+number of acetate groups). The degree of saponification can be determined in accordance with JIS K 6726:1994.

The polyvinyl alcohol-based resin may be partially modified modified polyvinyl alcohol. Examples include modifying polyvinyl alcohol-based resins with olefins such as ethylene and propylene; unsaturated carboxylic acids such as (meth)acrylic acid and crotonic acid; alkyl esters of unsaturated carboxylic acids, (meth)acrylamide, etc. modified polyvinyl alcohol. The proportion of modification is preferably less than 30 mol%, more preferably less than 10%. When the modification exceeds 30 mol%, the dichroic dye becomes difficult to adsorb, and it tends to be difficult to obtain a polarizer layer having sufficient polarization performance.

The average degree of polymerization of the polyvinyl alcohol-based resin is preferably from 100 to 10,000, more preferably from 1,500 to 8,000, and even more preferably from 2,000 to 5,000. The average degree of polymerization of polyvinyl alcohol-type resin can also be calculated|required based on JISK6726:1994.

The method of applying the above-mentioned coating liquid to the base film 30 can be appropriately selected from: wire bar coating; roll coating such as reverse coating and gravure coating; die coating; comma coating; Die lip coating method; spin coating method; screen coating method; fountain coating method; dip coating method; spray coating method and other methods.

The drying temperature and drying time of the coating layer (polyvinyl alcohol-based resin layer before drying) are set according to the type of solvent contained in the coating liquid. The drying temperature is, for example, 50 to 200°C, preferably 60 to 150°C. When the solvent contains water, the drying temperature is preferably 80° C. or higher.

The polyvinyl alcohol-type resin layer 6 may be formed in only one surface of the base film 30, and may be formed in both surfaces. When formed on both sides, it is possible to suppress the curling of the film that may occur during the manufacture of the polarizing laminated film 300 (see FIG. 4 ), and two polarizing plates can be obtained from one polarizing laminated film 300. It is also beneficial in terms of production efficiency.

The thickness of the polyvinyl alcohol-based resin layer 6 in the laminated film 100 is preferably 3 to 30 μm, more preferably 5 to 20 μm. If it is a polyvinyl alcohol-based resin layer 6 having a thickness within this range, through the stretching step S20 and the dyeing step S30 described later, it is possible to obtain a dichroic dye with good dyeability, excellent polarization performance, and sufficiently thin ( For example, the polarizer layer 5 having a thickness of 10 μm or less).

Before the coating of the coating liquid, in order to improve the adhesiveness between the base film 30 and the polyvinyl alcohol-based resin layer 6, electrolysis can be performed on at least the surface of the base film 30 on the side where the polyvinyl alcohol-based resin layer 6 is to be formed. Halo treatment, plasma treatment, flame treatment, etc. In addition, for the same reason, the polyvinyl alcohol-based resin layer 6 may be formed on the base film 30 via a primer layer or the like. The undercoat layer may also play a role of enabling peeling of the base film 30 from the polarizer layer 5 .

The undercoat layer can be formed by applying the coating liquid for undercoat layer formation to the surface of the base film 30 and then drying it. This coating liquid contains the component which exerts some strong adhesive force to both the base film 30 and the polyvinyl-alcohol-type resin layer 6, and usually contains the resin component and the solvent which provide such an adhesive force. As the resin component, it is preferable to use a thermoplastic resin excellent in transparency, thermal stability, stretchability, etc., and examples thereof include (meth)acrylic resins, polyvinyl alcohol-based resins, and the like. Among them, it is preferable to use a polyvinyl alcohol-based resin capable of imparting good adhesion. More preferably, it is a polyvinyl alcohol resin. As a solvent, a common organic solvent or aqueous solvent capable of dissolving the above-mentioned resin components is usually used, and it is preferable to form an undercoat layer from a coating solution using water as a solvent.

In order to increase the strength of the undercoat layer, a crosslinking agent may be added to the coating liquid for undercoat layer formation. Specific examples of the crosslinking agent include epoxy-based, isocyanate-based, dialdehyde-based, metal-based (eg, metal salts, metal oxides, metal hydroxides, organometallic compounds), and polymer-based crosslinking agents. When polyvinyl alcohol-based resin is used as the resin component for forming the undercoat layer, polyamide epoxy resin, methylolated melamine resin, dialdehyde-based crosslinking agent, metal chelate compound-based crosslinking agent, etc. are preferably used.

The thickness of the undercoat layer is preferably about 0.05 to 1 μm, more preferably 0.1 to 0.4 μm. When the thickness is within this range, moderate adhesion between the base film 30 and the polyvinyl alcohol-based resin layer 6 is easily obtained.

The method of applying the coating liquid for undercoat layer formation to the base film 30 can be the same as the coating liquid for polyvinyl-alcohol-type resin layer formation. The drying temperature of the coating layer formed from the coating liquid for forming an undercoat layer is, for example, 50 to 200°C, preferably 60 to 150°C. When the solvent contains water, the drying temperature is preferably 80° C. or higher.

[2] Stretching process S20

Referring to Fig. 3 , this step is a step of stretching the laminated film 100 to obtain a stretched laminated film 200 including a stretched base film 30' and a stretched polyvinyl alcohol-based resin layer 6'. Stretching is usually uniaxial stretching. Stretching process S20 can be performed continuously, conveying the long laminated film 100, for example. The film conveyance can be performed using guide rollers or the like.

The stretch ratio of the laminated film 100 can be appropriately selected according to desired polarization characteristics, and is preferably more than 5 times and 17 times or less, more preferably more than 5 times and 8 times or less, relative to the original length of the laminated film 100 . When the draw ratio is 5 times or less, the polyvinyl alcohol-based resin layer 6' cannot be sufficiently oriented, and thus the degree of polarization of the polarizer layer 5 may not be sufficiently high. On the other hand, when the stretching ratio is greater than 17 times, film breakage tends to occur during stretching, and the thickness of the stretched laminated film 200 becomes thinner than necessary, which may lower processability and handleability in subsequent steps.

The stretching treatment is not limited to one-stage stretching, and multistage stretching may be performed. In this case, all the stages of the multi-stage stretching treatment may be continuously performed before the dyeing step S30, or the second stage and subsequent stretching treatments may be performed simultaneously with the dyeing treatment and/or crosslinking treatment in the dyeing step S30. . When carrying out the multi-stage stretching treatment in this way, it is preferable to carry out the stretching treatment so that the sum of all stages of the stretching treatment becomes a stretching ratio greater than 5 times.

The stretching treatment may be longitudinal stretching in which the film is stretched in the longitudinal direction (film transport direction), or transverse stretching or diagonal stretching in which the film is stretched in the width direction. Examples of the longitudinal stretching method include inter-roll stretching using rolls (nip rolls, etc.), compression stretching, stretching using chucks (clamps), and hot roll stretching using heated rolls. Examples of the transverse stretching method include a tenter method and the like. For the stretching treatment, any of a wet stretching method and a dry stretching method may be used.

The stretching temperature is set to be higher than the temperature at which the polyvinyl alcohol-based resin layer 6 and the base film 30 can be stretched as a whole, and is preferably the phase transition temperature (melting point or glass transition temperature) of the base film 30. The range of -30°C to phase transition temperature +30°C, more preferably the range of phase transition temperature -30°C to phase transition temperature +5°C, more preferably the range of phase transition temperature -25°C to phase transition temperature +0°C . When the base film 30 contains several resin layers, the said phase transition temperature means the highest phase transition temperature among the phase transition temperatures which these several resin layers show.

If the stretching temperature is lower than the phase transition temperature -30° C., it will be difficult to achieve high-ratio stretching of more than 5 times, or the fluidity of the base film 30 will tend to be too low, making it difficult to stretch. If the stretching temperature is higher than the phase transition temperature + 30° C., the fluidity of the base film 30 tends to be too high and stretching tends to be difficult. Since it is easier to achieve a high stretching ratio of more than 5 times, the stretching temperature is within the above range, and is more preferably 120° C. or higher.

The heating method of the laminated film 100 in the stretching process includes: a zone heating method (for example, a method of heating in a stretching zone such as a heating furnace adjusted to a predetermined temperature by blowing hot air); Next, a method of heating the roll itself; a heater heating method (a method of installing infrared heaters, halogen heaters, flat heaters, etc. on the upper and lower sides of the laminated film 100 to heat with radiant heat), and the like. Among the roll-to-roll stretching methods, the zone heating method is preferable from the viewpoint of the uniformity of the stretching temperature.

Before the stretching step S20, a preheating step of preheating the laminated film 100 may be provided. As the preheating method, the same method as the heating method in the stretching treatment can be used. The preheating temperature is preferably in the range of stretching temperature -50°C to stretching temperature ±0°C, more preferably in the range of stretching temperature -40°C to stretching temperature -10°C.

In addition, a heat setting treatment step may be provided after the stretching treatment in the stretching step S20. The heat setting treatment is a process of performing heat treatment at a temperature equal to or higher than the crystallization temperature of the polyvinyl alcohol-based resin while maintaining a tensioned state with the ends of the stretch laminated film 200 held by clips. Crystallization of the polyvinyl alcohol-based resin layer 6' is accelerated by this thermal fixing treatment. The temperature of the heat setting treatment is preferably in the range of stretching temperature -0°C to stretching temperature -80°C, more preferably in the range of stretching temperature -0°C to stretching temperature -50°C.

[3] Dyeing process S30

Referring to FIG. 4 , this process is as follows: the polyvinyl alcohol-based resin layer 6' of the stretched laminated film 200 is dyed with a dichroic dye and subjected to adsorption orientation to form the polarizer layer 5 . Through this step, the polarizing laminated film 300 in which the polarizer layer 5 is laminated on one side or both sides of the base film 30' can be obtained. In dyeing process S30, dyeing process S30 can be performed continuously, conveying the long stretched laminated film 200, for example. The film conveyance can be performed using guide rollers or the like.

Specific examples of the dichroic dye include iodine and dichroic organic dyes. Specific examples of dichroic organic dyes include, for example, red BR, red LR, red R, pink LB, jade red BL, bordeaux GS, sky blue LG, tartrazine, blue BR, blue 2R, navy blue RY, green LG, purple LB, Purple B, Black H, Black B, Black GSP, Yellow 3G, Yellow R, Orange LR, Orange 3R, Scarlet GL, Scarlet KGL, Congo Red, Bright Purple BK, Sprague Blue G, Sprague Blue GL, Sri Lanka Pura Orange GL, Direct Sky Blue, Direct Firm Orange S, Firm Black. The dichroic dye may be used alone or in combination of two or more.

The dyeing step S30 can be performed by immersing the stretched laminated film 200 in a solution (dyeing bath) containing a dichroic dye. As the dyeing bath, a solution obtained by dissolving the aforementioned dichroic dye in a solvent can be used. Water is usually used as a solvent for the dyeing solution, and an organic solvent compatible with water may be further added. The concentration of the dichroic dye in the dyeing bath is preferably 0.01 to 10% by weight, more preferably 0.02 to 7% by weight.

When using iodine as a dichroic dye, since dyeing efficiency can be improved, it is preferable to further add iodide to the dyeing bath containing iodine. Examples of iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, titanium iodide and the like. The concentration of iodide in the dyeing bath is preferably 0.01 to 20% by weight. Among iodides, potassium iodide is preferably added. When potassium iodide is added, the ratio of iodine to potassium iodide is preferably 1:5 to 1:100 by weight ratio, and more preferably 1:6 to 1:80. The temperature of the dyeing bath is preferably 10 to 60°C, more preferably 20 to 40°C.

It should be noted that an additional stretching process may be further applied to the stretched laminated film 200 in the dyeing step S30. The embodiment at this time enumerates the following schemes, etc.: 1) In the above-mentioned stretching step S20, after the stretching treatment is performed at a ratio lower than the target ratio, the stretching treatment is performed in the dyeing treatment in the dyeing step S30 so that the total stretching ratio reaches Target magnification; as described later, in the case of performing cross-linking treatment after dyeing treatment, 2) In the above-mentioned stretching step S20, after performing stretching treatment at a ratio lower than the target magnification, in the dyeing treatment in dyeing step S30 The stretching treatment is performed until the total stretching ratio does not reach the target ratio, and then the stretching treatment is performed in the crosslinking treatment so that the final total stretching ratio reaches the target ratio.

In order to enable good orientation of the dichroic dye adsorbed on the polyvinyl alcohol-based resin layer, it is preferable to carry out the dyeing step S30 after stretching the laminated film 100 at least to a certain extent.

The dyeing step S30 may include a cross-linking step performed after the dyeing step. The crosslinking treatment step can be carried out by immersing the dyed stretched laminated film in a solution (crosslinking bath) containing a crosslinking agent. Examples of the crosslinking agent include boric acid, boron compounds such as borax, glyoxal, glutaraldehyde, and the like. One type of crosslinking agent may be used alone, or two or more types may be used in combination. As the crosslinking bath, a solution obtained by dissolving a crosslinking agent in a solvent can be used. As the solvent, water may be used, and an organic solvent compatible with water may be further included. The concentration of the crosslinking agent in the crosslinking bath is preferably 1 to 20% by weight, more preferably 6 to 15% by weight.

The crosslinking bath may further contain iodide. The addition of iodide can make the in-plane polarization characteristics of the polarizer layer 5 more uniform. Specific examples of iodide are the same as above. The concentration of iodide in the crosslinking bath is preferably 0.05 to 15% by weight, more preferably 0.5 to 8% by weight. The temperature of the crosslinking bath is preferably 10 to 90°C.

In addition, the crosslinking treatment can also be performed simultaneously with the dyeing treatment by mixing a crosslinking agent in the dyeing bath. In addition, two or more types of cross-linking baths having different compositions may be used, and the treatment of immersion in the cross-linking bath may be performed two or more times. Stretching treatment may also be performed during crosslinking treatment. The specific scheme of carrying out the stretching treatment in the crosslinking treatment is as described above.

After the dyeing step S30, a washing step and a drying step may be performed. The washing process generally includes a water washing process. The water washing treatment can be performed by immersing the dyed or crosslinked membrane in pure water such as ion-exchanged water or distilled water. The water washing temperature is usually 3 to 50°C, preferably 4 to 20°C. The washing step may be a combination of a water washing step and a washing step using an iodide solution. For the drying step performed after the washing step, any appropriate method such as natural drying, air drying, and heat drying can be employed. For example, in the case of heat drying, the drying temperature is usually 20 to 95°C.

The thickness of the polarizer layer 5 included in the polarizing laminated film 300 is preferably 10 μm or less, more preferably 8 μm or less, and still more preferably 7 μm or less. A thin polarizing plate can be obtained by setting the thickness of the polarizing plate layer 5 to be 10 μm or less. The thickness of the polarizer layer 5 is usually 1 μm or more or 2 μm or more.

As described above, when a thermoplastic resin film is bonded to the polarizer layer using an active energy ray-curable adhesive, when the obtained polarizing plate is observed from the side of the thermoplastic resin film under a fluorescent lamp, the reflection on the surface of the thermoplastic resin film The image of the fluorescent lamp sometimes produces "image distortion". For image deformation, it is found that due to the curing shrinkage of the adhesive layer accompanied by the intense curing caused by the irradiation of active energy rays, and the deformation of the surface of the polarizer layer caused by the rapid application of heat from the active energy ray source, the polarizer Micro unevenness on the surface of the layer is accentuated, resulting in image deformation. Such accentuation of minute unevenness is likely to occur when the thickness of the polarizer layer 5 is small and the rigidity is low. Therefore, the present invention capable of suppressing image distortion is particularly advantageous when the thickness of the polarizer layer 5 is small, for example, when the thickness of the polarizer layer 5 is 10 μm or less, further 8 μm or less.

[4] Protective film lamination step S40

Referring to FIG. 5 , this step is a step of laminating the protective film 7 on the surface of the polarizing laminated film 300 on the polarizer layer 5 side to obtain a polarizing laminated film 400 with a protective film. The protective film 7 is preferably laminated on the polarizer layer 5 so as to be in contact with the surface of the polarizer layer 5 (the surface opposite to the base film 30'). When the polarizing layer 5 is laminated on both surfaces of the base film 30', a protective film 7 may be laminated on each polarizing layer 5.

The protective film lamination step S40 includes, for example, the steps of laminating the long polarizing laminated film 300 and the protective film 7 while conveying them, and passing the laminated body between a pair of rollers (bonding rollers). press. The film conveyance can be performed using guide rollers or the like. The pressure (nip pressure) applied to the said laminate by the bonding roll is 0.05-2 MPa, for example, Preferably it is 0.08-1 MPa.

As the protective film 7, the arithmetic mean roughness Ra of the surface on the polarizer layer 5 side is 0.150 micrometers or less. Use of the protective film 7 is advantageous in suppressing image distortion that may occur in a polarizing plate formed by bonding a thermoplastic resin film to the polarizer layer 5 using an active energy ray-curable adhesive.

For example, in the case of a manufacturing method in which the polarizing laminated film 300 is directly supplied to the polarizing plate manufacturing process without laminating a protective film on the polarizing plate layer 5, the polarizing plate layer 5 is particularly easily scratched and easily damaged. When the permanent laminated film 300 is used, the polarizer layer 5 is easily scratched or damaged. In addition, when the protective film is not laminated on the polarizing plate layer 5, it is difficult to wind up the polarizing laminated film 300 once to make a roll, and even if it can be made into a roll, scratches are likely to occur during winding. ,damaged.

Lamination of the protective film 7 prevents or suppresses scratches and breakages on the surface of the polarizer layer 5 , and the polarizing laminated film with a protective film 400 can be wound up to form a roll. If it is made into a roll form, it can be temporarily stored in a warehouse (or managed as inventory in advance) as a manufacturing intermediate to be supplied to the polarizing plate manufacturing process, etc., so that the degree of freedom and efficiency of the polarizing plate manufacturing process can be improved. . From these viewpoints, it is advantageous to laminate the protective film 7 on the polarizer layer 5 .

However, it has been found that when the protective film is laminated on the polarizer layer 5, compared with the case where the polarizing laminated film 300 is directly supplied to the polarizing plate manufacturing process without laminating the protective film, the active energy ray-curable adhesive is used on the polarizer. The polarizing plate obtained by laminating the thermoplastic resin film on the layer 5 tends to be image-distorted. Especially when the polarizing laminated film 400 with a protective film is wound up into a roll, or the roll is stored in a roll state for a certain period of time, image deformation is particularly likely to occur.

Image distortion can be suppressed by using the protective film 7 whose arithmetic mean roughness Ra of the surface on the polarizer layer 5 side is 0.150 micrometers or less. From the viewpoint of effectively suppressing image distortion, the arithmetic average roughness Ra is preferably 0.120 μm or less, more preferably 0.100 μm or less, further preferably 0.080 μm or less, and still more preferably 0.070 μm or less. The above-mentioned arithmetic average roughness Ra is usually 0.010 μm or more, for example, 0.020 μm or more (or 0.030 μm or more). The arithmetic mean roughness Ra in this specification is the arithmetic mean roughness Ra based on JISB 0601:2013, and can be measured by the method described in the item of the Example mentioned later, or the method substantially equivalent to it. For such a protective film, for example, an appropriate protective film can be selected and used according to the grade and the lot.

Examples of the protective film 7 include a thermoplastic resin film having self-adhesiveness, an adhesive film having an adhesive layer on a support film, and the like. The thermoplastic resin constituting the self-adhesive thermoplastic resin film is, for example, chain olefin-based resins such as polypropylene-based resins and polyethylene-based resins. The self-adhesive thermoplastic resin film may have a single-layer structure.

The support film constituting the above-mentioned adhesive film can be made of thermoplastic resins, such as polyolefin resins such as polyethylene resins, polypropylene resins, and cyclic polyolefin resins; polyethylene terephthalate, polyethylene naphthalate, etc. Polyester resins such as ethylene glycol; polycarbonate resins; (meth)acrylic resins, etc. The adhesive layer can be made of (meth)acrylic adhesive, epoxy adhesive, urethane adhesive, silicone adhesive, etc., preferably (meth)acrylic adhesive. mixture. The thickness of the adhesive layer is, for example, 1 to 40 μm, and may be 3 to 25 μm. When an adhesive film is used, the protective film 7 is laminated on the polarizing laminated film 300 via the adhesive layer of the protective film 7 .

The thickness of the protective film 7 may be, for example, 5-200 μm, preferably 10-150 μm, more preferably 20-120 μm, further preferably 25-100 μm (for example, 90 μm or less, further 75 μm or less).

The protective film 7 is laminated and adhered to the surface of the polarizing laminated film 300 on the polarizer layer 5 side (preferably the surface of the polarizer layer 5 ), and the protective film 7 can be peeled therefrom. The peeling force between the polarizing laminated film 300 and the protective film 7 is, for example, 0.01 to 0.5 N/25 mm, preferably 0.01 to 0.2 N/25 mm. When the peeling force is less than 0.01N/25mm, the adhesion force is too small, and the protective film 7 may be partially peeled during the handling of the polarizing laminated film 400 with a protective film, or the protection of the polarizer layer 5 may be insufficient. Moreover, when peeling force exceeds 0.5 N/25mm, it may become difficult to peel the protective film 7 from the polarizing laminated film 400 with a protective film.

The above-mentioned peeling force can be obtained by cutting the polarizing laminated film 400 with a protective film into a width of 25 mm to obtain a measurement sample, and using a precision universal testing machine "Autograph AGS-50NX" manufactured by Shimadzu Corporation or its equivalent. The device grasps the protective film 7 and the polarizing laminated film 300 of the measurement sample, and measures the force when peeling off in the 180° direction, thereby obtaining it. The measurement of the peeling force is carried out at a peeling speed of 300mm/min at a temperature of 23±2°C and a relative humidity of 50±5%.

[5] Other processes

The method for producing a polarizing laminated film with a protective film may include a winding step of winding the obtained polarizing laminated film with a protective film 400 by a common means to obtain a roll of polarizing laminated film with a protective film. . In addition, it may further include a storage step of storing the obtained polarizing laminated film coil with a protective film in a certain environment. A certain environment may be a normal storage environment, for example, an environment with a temperature of 23° C. and a relative humidity of 55%.

The storage time in the above-mentioned storage step may be within 2 years, preferably within 1.5 years, more preferably within 1 year, and even more preferably within 0.5 years. By keeping the storage time within 2 years, image deformation can be effectively suppressed, and deterioration of the physical properties of the polarizing plate layer 5 can be prevented. The lower limit value of storage time is not specifically limited, For example, it can be 4 hours or more.

The polarizing plate obtained by bonding the thermoplastic resin film to the polarizing plate layer 5 with an active energy ray-curable adhesive is prone to image deformation when the winding step, or the winding step and the storage step are included. Therefore, the present invention capable of suppressing image deformation is particularly advantageous when a winding step is included, or a winding step and a storage step are included.

<Polarizing laminated film with protective film and its roll>

The polarizing laminated film 400 with a protective film shown in FIG. 5 includes a base film 30', a polarizer layer 5 made of a polyvinyl alcohol-based resin, and a protective film 7 in this order. The arithmetic mean roughness of the surface of the protective film 7 on the polarizer layer 5 side is 0.150 μm or less. The polarizing laminated film roll with a protective film is a roll of the polarizing laminated film with a protective film 400 .

The polarizing laminated film with a protective film 400 and the roll of the polarizing laminated film with a protective film may include polarizer layers 5 laminated on both surfaces of the base film 7 .

In this case, the layer configuration of the polarizing laminated film 400 with a protective film and the roll of the polarizing laminated film with a protective film is, for example, protective film 7/polarizer layer 5/substrate film 30'/polarizer layer 5/ Protective film 7, protective film 7/polarizer layer 5/substrate film 30'/polarizer layer 5.

The protective film-attached polarizing laminated film 400 and the protective film-attached polarizing laminated film coil can be manufactured by the above-mentioned manufacturing method suitably. In this case, the base film is the stretched base film 30'. Moreover, it is also possible to laminate|stack and manufacture three separate members of a base film, a polarizing plate layer (polarizing film), and a protective film. In this case, the polarizer layer (polarizing film) may be a polyvinyl alcohol-based resin film manufactured by a known method from a monomer (individual) film containing a polyvinyl alcohol-based resin on which a dichroic dye is adsorbed and oriented. formed film. The thickness of the polarizer layer (polarizing film) may be, for example, 1 to 25 μm. The base film may be a stretched film or an unstretched film.

The protective film 7 is laminated on the polarizer layer 5, preferably in contact with the surface of the polarizer layer 5 (the surface opposite to the base film 30 or 30'). The polarizer layer 5 can be laminated on the base film 30 or 30' through the above-mentioned undercoat layer or the like. The base film 30 or 30' is preferably peelable from the polarizer layer 5. In addition, the base film 30 or 30' may be an optical film. In this case, a polarizing laminated film can be used as a polarizing plate.

A protective film 7 having an arithmetic average roughness Ra of 0.150 μm or less on the surface of the polarizing plate layer 5 is used, and a polarizing plate obtained by bonding a thermoplastic resin film to the polarizing plate layer 5 using an active energy ray-curable adhesive. This is advantageous in suppressing possible image distortion. From the viewpoint of effectively suppressing image distortion, the arithmetic average roughness Ra is preferably 0.120 μm or less, more preferably 0.100 μm or less, further preferably 0.080 μm or less, and still more preferably 0.070 μm or less. The above-mentioned arithmetic average roughness Ra is usually 0.010 μm or more, for example, 0.020 μm or more (or 0.030 μm or more).

From the viewpoint of suppressing image deformation, the arithmetic mean roughness Ra of the surface of the polarizer layer 5 on the protective film 7 side of the polarizing laminated film 400 with a protective film and the polarizing laminated film roll with a protective film is preferably 0.100. μm or less, more preferably 0.090 μm or less. This arithmetic average roughness Ra is usually 0.010 μm or more, for example, 0.020 μm or more (or 0.030 μm or more).

For the polarizing laminated film with a protective film 400 and the substrate film 30 or 30 ′, polarizer layer 5, and protective film 7 included in the polarizing laminated film roll with a protective film, the above-mentioned <Polarizing laminated film with a protective film The description about the base film 30 or 30', the polarizing plate layer 5, and the protective film 7 in the item of the manufacturing method of a film>.

＜Manufacturing method of polarizing plate＞

FIG. 6 is a flowchart showing a method of manufacturing a polarizing plate according to an embodiment of the present invention. As shown in FIG. 6, the manufacturing method of the polarizing plate related to one embodiment of the present invention includes the following steps:

A step of obtaining a polarizing laminated film with a protective film by the above-mentioned method for producing a polarizing laminated film with a protective film;

Protective film peeling process S50, peeling the protective film from the polarizing laminated film with protective film;

In the first bonding step S60, a first thermoplastic resin film is laminated via a layer of an active energy ray-curable adhesive on the surface of the polarizing laminated film on the polarizer layer side exposed in the protective film peeling step S50; and

In the curing step S70, the layer of the active energy ray-curable adhesive is cured.

The manufacturing method of a polarizing plate may further include the base film peeling process which peels a base film after hardening process S70. In addition, although not shown in FIG. 6 , the method of manufacturing a polarizing plate may further include: removing the polarizing laminated film with a protective film between the step of obtaining the polarizing laminated film with a protective film and the protective film peeling step S50. A step of winding up to obtain a polarizing laminated film roll with a protective film. About the process of obtaining the polarizing laminated film roll material with a protective film, it is as having already mentioned above. When the step of obtaining a polarizing laminated film roll with a protective film is included, the protective film peeling step S50 may be: the polarizing laminated film with a protective film unwound from the polarizing laminated film roll with a protective film The process of peeling off the protective film.

Hereinafter, each of the above-mentioned steps will be described with reference to the drawings.

[1] Process for obtaining a polarizing laminated film with a protective film

For this step, the description in the section of the aforementioned <Protective Film-attached Polarizing Laminated Film Manufacturing Method> is cited.

[2] Protective film peeling process S50

Referring to FIG. 7 , this step is a step of peeling the protective film 7 from the polarizing laminated film 400 with a protective film to obtain a film having the same layer configuration as the polarizing laminated film 300 . For this step, for example, the long polarizing laminated film with a protective film 400 can be continuously conveyed, or the polarizing laminated film with a protective film can be continuously unwound from a roll of polarizing laminated film with a protective film. 400 and transfer it, while performing the process continuously. The film conveyance can be performed using guide rollers or the like. A specific method for peeling off the protective film 7 may be a common peeling method for a protective film.

From the viewpoint of suppressing image deformation, the arithmetic mean roughness Ra of the surface on the polarizer layer 5 side (or the surface of the polarizer layer 5 ) exposed by peeling of the protective film 7 is preferably 0.100 μm or less, more preferably 0.090 μm the following. This arithmetic average roughness Ra is usually 0.010 μm or more, for example, 0.020 μm or more (or 0.030 μm or more).

[3] First bonding process S60

Referring to FIG. 8, this step is: on the surface of the polarizer layer 5 side of the film having the same layer configuration as the polarizing laminated film 300 obtained in the protective film peeling step S50, which is exposed by the protective film peeling step S50, A step of laminating the first thermoplastic resin film 10 through a layer of an active energy ray-curable adhesive. This step includes, for example, the step of continuously conveying a long film having the same layer configuration as that of the polarizing laminated film 300 and a long first thermoplastic resin film 10, And/or one surface of the first thermoplastic resin film 10 is coated with an active energy ray-curable adhesive, and these films are laminated via a layer of the active energy ray-curable adhesive, and the laminate is passed through a pair of rollers. Press between (bonding rollers) in this way.

The first adhesive layer 15 shown in FIG. 8 is a cured product layer of an active energy ray-curable adhesive layer cured in a curing step S70 described later. The first polarizing plate 500 shown in FIG. 8 is a polarizing plate including the first thermoplastic resin film 10 as an optical film on one surface of the polarizing plate layer 5, and a base film 30' on the other surface.

When the polarizing laminated film 300 has the polarizing layer 5 on both sides of the base film 30', the first thermoplastic resin film 10 is usually bonded to the polarizing layer 5 on both sides. In this case, these first thermoplastic resin films 10 may be the same type of thermoplastic resin film or may be different types of thermoplastic resin films in terms of resin type and structure.

The layer of the active energy ray-curable adhesive is usually in contact with the surface of the polarizer layer 5 and the surface of the first thermoplastic resin film 10 .

The first thermoplastic resin film 10 is an optical film, and may contain a light-transmitting (preferably optically transparent) thermoplastic resin, such as a chain polyolefin resin (polypropylene resin, etc.), a cyclic polyolefin resin ( polyolefin-based resins such as norbornene-based resins); cellulose ester-based resins such as triacetyl cellulose and diacetyl cellulose; polyester-based resins; polycarbonate-based resins; (meth)acrylic resins resin; polystyrene-based resin; or a film of a mixture, a copolymer, or the like thereof. Among them, the first thermoplastic resin film 10 is a thermoplastic resin film with low moisture permeability that is not necessarily easy to bond when using a water-based adhesive, such as polyolefin-based resin, polyester-based resin, (meth)acrylic resin, polyphenylene resin, etc. Thermoplastic resin films such as vinyl resins. As for the specific example of the said thermoplastic resin, the description about a base film is referred.

The first thermoplastic resin film 10 may be a protective film for protecting the polarizer layer 5 , or a protective film having optical functions such as retardation film and brightness enhancement film. For example, by stretching (uniaxially stretching or biaxially stretching, etc.) a film containing the above-mentioned thermoplastic resin, or forming a liquid crystal layer on the film, it is possible to make a phase difference that imparts an arbitrary phase difference value. membrane.

On the surface of the first thermoplastic resin film 10 opposite to the polarizer layer 5, surface treatment layers (coating layers) such as a hard coat layer, an antiglare layer, an antireflection layer, an antistatic layer, and an antifouling layer may be formed. . The surface treatment layer may be formed in advance on the first thermoplastic resin film 10 before the first bonding step S60 is performed, or may be formed after the first bonding step S60 or the peeling step S80 described later. In addition, the first thermoplastic resin film 10 may contain one or more additives such as lubricants, plasticizers, dispersants, heat stabilizers, ultraviolet absorbers, infrared absorbers, antistatic agents, and antioxidants.

From the viewpoint of thinning the polarizing plate, the thickness of the first thermoplastic resin film 10 is preferably 90 μm or less, more preferably 50 μm or less, and still more preferably 30 μm or less. From the viewpoint of strength and handleability, the thickness of the first thermoplastic resin film 10 is usually 5 μm or more.

Accentuation of minute unevennesses on the surface of the polarizer layer 5 tends to occur when the thickness of the first thermoplastic resin film 10 is small and the rigidity is low. Therefore, the present invention capable of suppressing image distortion is particularly advantageous when the thickness of the first thermoplastic resin film 10 is small, for example, when the thickness of the first thermoplastic resin film 10 is 30 μm or less.

The first adhesive layer 15 is a layer for bonding and fixing the first thermoplastic resin film 10 to one surface of the polarizer layer 5 . The adhesive forming the first adhesive layer 15 is an active energy ray-curable adhesive containing a curable compound that is cured by irradiation with active energy rays such as ultraviolet rays, visible light, electron rays, and X-rays, preferably UV curable adhesive.

The aforementioned curable compound may be a cation polymerizable curable compound or a radical polymerizable curable compound. Examples of cationic polymerizable curable compounds include epoxy-based compounds (compounds having one or more epoxy groups in the molecule), oxetane-based compounds (compounds having one or two or more epoxy groups in the molecule). more than one oxetane ring compound), or a combination thereof. Examples of radically polymerizable curable compounds include (meth)acrylic compounds (compounds having one or more (meth)acryloyloxy groups in the molecule), radically polymerizable bis Bonded other vinyl compounds, or combinations thereof. A cation polymerizable curable compound and a radical polymerizable curable compound may be used in combination. The active energy ray-curable adhesive generally further includes a cationic polymerization initiator and/or a radical polymerization initiator for initiating the curing reaction of the above-mentioned curable compound.

The active energy ray-curable adhesive may contain cationic polymerization accelerators, ion-scavenging agents, antioxidants, chain transfer agents, tackifiers, thermoplastic resins, fillers, flow regulators, plasticizers, defoamers, Antistatic agent, leveling agent, solvent and other additives.

When bonding the first thermoplastic resin film 10 on the polarizer layer 5, in order to improve the adhesiveness with the polarizer layer 5, plasma can be carried out to the bonding surface of the first thermoplastic resin film 10 and/or the polarizer layer 5. Surface treatment (adhesion-prone treatment) such as surface treatment, corona treatment, ultraviolet irradiation treatment, flame treatment, and saponification treatment, among which plasma treatment, corona treatment, or saponification treatment is preferably performed.

[4] Curing process S70

Referring to FIG. 8 , this step is a step of curing the active energy ray-curable adhesive layer of the laminate obtained in the first bonding step S60 to obtain the first polarizing plate 500 . Curing of the layer can be performed by irradiating the layer with active energy rays. Among them, ultraviolet light is suitable. At this time, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, etc. can be used as light sources.

The thickness (after curing) of the first adhesive layer 15 is usually about 0.001 to 5 μm, preferably 0.01 to 3 μm.

Since the first polarizing plate 500 obtained as described above is manufactured using the above-mentioned polarizing laminated film with a protective film 400 , image distortion can be effectively suppressed when viewed from the first thermoplastic resin 10 side.

From the viewpoint of suppressing image distortion, the arithmetic average roughness Ra of the surface of the first thermoplastic resin film 10 side of the polarizer layer 5 included in the first polarizing plate 500 is preferably 0.100 μm or less, more preferably 0.090 μm or less. This arithmetic average roughness Ra is usually 0.010 μm or more, for example, 0.020 μm or more (or 0.030 μm or more).

[5] Substrate film peeling process S80

Referring to FIG. 9 , the method of manufacturing a polarizing plate may further include a substrate film peeling step S80 of peeling the substrate film 30' after the curing step S70. Thus, the second polarizing plate 600 including the first thermoplastic resin film 10 on one surface of the polarizing plate layer 5 can be obtained. For this step, for example, the elongated first polarizing plate 500 may be continuously conveyed, or the first polarizing plate 500 may be continuously unwound from a roll material of the elongated first polarizing plate 500 and This step is continuously carried out while being conveyed. The film conveyance can be performed using guide rollers or the like. A specific method for peeling the base film 30' may be a common peeling method for the base film 30'.

When the second polarizing plate 600 is incorporated into an image display device such as a liquid crystal display device, it is preferable that the first thermoplastic resin film 10 is arranged on the outer side of the polarizer layer 5 (opposite to the image display element). The same applies to the first polarizing plate 500 . Thereby, the side of the 1st thermoplastic resin film 10 which suppressed image deformation can be made to face the viewing side of an image display apparatus. The bonding of the second polarizing plate 600 and the first polarizing plate 500 to the image display element (such as a liquid crystal cell) can be performed through an adhesive layer.

The adhesive forming the adhesive layer generally comprises an adhesive composition using (meth)acrylic resin, styrene resin, silicone resin, etc. as a base polymer, wherein There are crosslinking agents such as isocyanate compounds, epoxy compounds, and aziridine compounds. In addition, fine particles may be contained to form a light-scattering pressure-sensitive adhesive layer. The thickness of the pressure-sensitive adhesive layer is usually 1 to 40 μm, preferably 3 to 25 μm.

[6] Other processes

The method of manufacturing the polarizing plate may include a step of bonding the second thermoplastic resin film 20 to the other surface of the polarizer layer 5 included in the second polarizing plate 600 via an adhesive. Thus, referring to FIG. 10, it can be obtained that the first thermoplastic resin film 10 is pasted on one side of the polarizer layer 5 through the first adhesive layer 15, and the other side is pasted through the second adhesive layer 25. The third polarizing plate 700 incorporating the second thermoplastic resin film 20 is incorporated.

The second thermoplastic resin film 20 is an optical film. Like the first thermoplastic resin film 10, it can be a protective film containing the thermoplastic resins exemplified above, or it can be a protective film with optical functions such as retardation film and brightness enhancement film. membrane. For the surface treatment layer and the thickness of the film that the second thermoplastic resin film 20 may have, the description above that described the first thermoplastic resin film 10 is cited. Both the first thermoplastic resin film 10 and the second thermoplastic resin film 20 may be films containing the same resin, or may be films containing different types of resin.

The second adhesive layer 25 is a layer for bonding and fixing the second thermoplastic resin film 20 on the other side of the polarizer layer 5. Like the first adhesive layer 15, in order to be directly bonded to the polarizer layer 5, Usually, it is laminated|stacked in contact with the said other surface of the polarizer layer 5. Moreover, the 2nd adhesive bond layer 25 is also normally in contact with the bonding surface (surface on the polarizer layer 5 side) of the 2nd thermoplastic resin film 20. As shown in FIG.

The adhesive forming the second adhesive layer 25 may be a water-based adhesive in which an adhesive component such as polyvinyl alcohol-based resin is dissolved or dispersed in water, in addition to an active energy ray-curable adhesive. Similar to the first adhesive layer 15 , it is preferably an active energy ray-curable adhesive from the viewpoint of production efficiency. In particular, when the moisture permeability of the second thermoplastic resin film 20 is low, it is preferable to use an active energy ray-curable adhesive. The active energy ray-curable adhesive forming the second adhesive layer 25 is preferably an ultraviolet curable adhesive.

In the third polarizing plate 700, the second thermoplastic resin film 20 may be laminated on the other side of the polarizer layer 5 via an adhesive layer. Regarding the pressure-sensitive adhesive layer, the description above is cited.

When the third polarizing plate 700 is incorporated into an image display device such as a liquid crystal display device, it is preferable that the second thermoplastic resin film 20 is arranged on the image display element side with respect to the polarizer layer 5 . Thereby, the side of the 1st thermoplastic resin film 10 which suppressed image deformation can be made to face the viewing side of an image display apparatus. The bonding of the third polarizing plate 700 to the image display element (such as a liquid crystal cell) can be performed through an adhesive layer.

[Example]

Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not limited to these examples.

In the following examples and comparative examples, the arithmetic average roughness Ra of the surface of the protective film and the surface of the polarizer layer was measured according to the following method.

(Measurement of arithmetic average roughness Ra)

The arithmetic mean roughness Ra according to JIS B 0601:2013 was measured using the white interferometer "Vertscan" (manufactured by Ryoka Systems Co., Ltd.) which is a non-contact surface roughness measuring device. The white interferometer uses a CCD camera to capture the interference fringes caused by the optical path difference caused by the unevenness of the sample surface, and converts the light and dark information of the interference fringes into the height information of the surface unevenness.

The measurement procedure of the arithmetic average roughness Ra is as follows. First, a film piece of 20 cm×20 cm is cut out from a film to be measured. This film piece was placed on a black acrylic plate with the surface to be measured facing up, and the periphery was fixed with tape to flatten the surface to be measured. The obtained laminate was used as a measurement sample.

The measurement sample was placed on the stage of the white interferometer "Vertscan", and the measurement was performed with the following device settings, and the arithmetic mean roughness Ra was obtained.

The magnification of double-beam interference objective lens: 5 times

Measurement mode: select "wave"

Wavelength filter: select "530white"

Scanning area: -10μm～10μm

Stitching setting: 2×2, overlap rate 20%.

Based on the above settings, the observation range is as follows.

·Vertical (x) × horizontal (y): 1263.73μm × 1689.94μm

·Height difference (z): -0.25μm～0.25μm.

<Example 1>

(1) Preparation of coating solution

Polyvinyl alcohol powder (“Z-200” manufactured by Nippon Synthetic Chemical Industry Co., Ltd., average degree of polymerization 1100, saponification degree 99.5 mol%) was dissolved in hot water at 95°C to prepare an aqueous solution of polyvinyl alcohol with a concentration of 3% by weight. . In the obtained aqueous solution, a crosslinking agent ("Sumirez Resin 650" manufactured by Tagoka Chemical Industry Co., Ltd.) was mixed in a ratio of 1 part by weight to 2 parts by weight of polyvinyl alcohol powder to obtain a coating for forming an undercoat layer. liquid.

Separately, polyvinyl alcohol powder (“PVA124” manufactured by Kuraray Co., Ltd., average degree of polymerization 2400, saponification degree 98.0 to 99.0 mol%) was dissolved in hot water at 95°C to prepare an aqueous solution of polyvinyl alcohol having a concentration of 8% by weight. A coating solution for forming a polyvinyl alcohol-based resin layer.

(2) Formation of primer layer and polyvinyl alcohol-based resin layer (production of laminated film)

Next, corona treatment was performed on one side of a substrate film (melting point: 163° C.) with a thickness of 90 μm (melting point: 163° C.) made of polypropylene, and then continuously coated on the corona-treated surface using a small-diameter gravure coater. The above coating liquid for forming an undercoat layer was dried at 60° C. for 3 minutes to form an undercoat layer having a thickness of 0.2 μm. Next, while continuously conveying the film, the above-mentioned coating liquid for forming a polyvinyl alcohol-based resin layer was applied to the surface of the undercoat layer on the base film using a lip coater, and then dried at 80° C. for 8 minutes, whereby A polyvinyl alcohol-based resin layer with a thickness of 9.3 μm was formed on the undercoat layer to obtain a laminated film.

(3) Stretching process (production of stretched laminated film)

While continuously conveying the laminated film obtained in (2) above, after performing longitudinal uniaxial stretching by inter-roll stretching using nip rolls at a stretching temperature of 140° C. to a stretch ratio of 2.5 times, similarly stretching by using nip rolls Between-roll stretching with holding rolls Longitudinal uniaxial stretching was performed at a stretching temperature of 160° C. until the total stretching ratio reached 5.8 times to obtain a stretched laminated film. The stretched polyvinyl alcohol-based resin layer in the stretched laminated film had a thickness of 5.1 μm.

(4) Dyeing process (production of polarizing laminated film)

After the stretched film obtained in the above (3) is conveyed continuously, the polyvinyl alcohol-based resin layer is dyed by immersing it in a 30° C. dyeing aqueous solution containing iodine and potassium iodide for a residence time of about 150 seconds. , using pure water at 10°C to wash away excess dyeing aqueous solution. Next, immersion was performed continuously for a residence time of 600 seconds in a 76° C. crosslinking aqueous solution containing boric acid and potassium iodide to perform a crosslinking treatment. Thereafter, it was washed with pure water at 10° C. for 4 seconds, and dried at 80° C. for 300 seconds to obtain a polarizing laminated film having a polarizer layer on a base film. The thickness of the polarizer layer was 5.1 μm.

A film sheet was cut out from the obtained polarizing laminated film, and the arithmetic average roughness Ra of the surface of the polarizer layer (the surface opposite to the base film) was measured according to the above-mentioned measurement procedure, and it was 0.0456 μm.

(5) Protective film lamination process (production of polarizing laminated film with protective film)

While continuously conveying the polarizing laminated film obtained in (4) above, the protective film A (polyethylene-based resin film having self-adhesiveness) with a thickness of 30 μm was calculated according to the surface of the polarizer layer side in the above-mentioned measurement procedure. Average roughness Ra: 0.0815 μm) was laminated on the surface of the polarizer layer, the laminate was passed through a bonding roller to press the laminate to perform bonding treatment, and the laminate after the bonding treatment was continuously wound up to obtain Polarizing laminated film roll with protective film. The protective film A is in contact with the surface of the polarizer layer. The pressure (nipping pressure) applied to the above laminate by the bonding roll was 0.1 MPa.

It should be noted that the nip pressure of the laminating rollers is obtained as follows: a pressure-sensitive paper [Fuji Film Co., Ltd. for Prescale ultra-ultra-low pressure (LLLW)] is set on the pressing part between the laminating rollers, and after pressing, use The pressure measuring system [FPD-305E and FPS-307E manufactured by Fujifilm Co., Ltd.] measures the clamping pressure of the pressed portion and obtains it in advance.

The obtained polarizing laminated film roll with a protective film was stored in an environment with a temperature of 23° C. and a relative humidity of 55% for two weeks.

(6) Production of polarizing plate

While continuously unwinding the polarizing laminated film with a protective film from the polarizing laminated film roll with a protective film immediately after the above-mentioned storage, the protective film A was peeled off continuously. The arithmetic average roughness of the surface of the polarizer layer (the surface opposite to the base film) exposed by peeling the protective film A according to the above measurement procedure after cutting out the polarizing laminated film obtained by peeling the protective film A Ra was measured and the result was 0.0998 μm.

Next, a UV-curable adhesive ("KR-75T" manufactured by ADEKA Co., Ltd.) was applied to the surface of the polarizer layer exposed by the peeling of the protective film A using a small-diameter gravure coater so that the thickness after curing was about 1.0. μm, a thermoplastic resin film ("ZF-14" manufactured by Nippon Zeon Co., Ltd.) with a thickness of 23 μm made of cyclic polyolefin resin is laminated on the adhesive layer, and the laminate is passed through a bonding roller. The laminated body was pressed to carry out the bonding process, and then, the adhesive layer was cured by irradiating ultraviolet rays with a cumulative light intensity of 200 mJ/cm ² from the base film side using a high-pressure mercury lamp, thereby obtaining the polarizer layer. A polarizing plate in which a thermoplastic resin film is laminated on one side with a cured adhesive layer interposed therebetween, and a base film is provided on the other side.

Next, the base film was peeled off while conveying the obtained polarizing plate continuously, and the polarizing plate in which the thermoplastic resin film was laminated|stacked on one surface of the polarizing plate layer via the adhesive bond layer after hardening was obtained.

(7) Evaluation of image deformation

Under a fluorescent lamp, the polarizing plate (obtained by peeling the base film) obtained in the above (6) was visually observed from the thermoplastic resin film side, and the deformation of the image of the fluorescent lamp reflected on the surface of the thermoplastic resin film was determined. The degree is evaluated according to the following evaluation criteria. The results are shown in Table 1.

A: In the image of the fluorescent lamp, the outline of the fluorescent lamp is completely or substantially not deformed, which is relatively better than the following B.

B: In the image of the fluorescent lamp, the outline of the fluorescent lamp is slightly deformed, which is relatively better than the following C.

C: In the image of the fluorescent lamp, a large amount of deformation can be confirmed in the outline of the fluorescent lamp.

<Examples 2 to 3, Comparative Example 1>

Except for using the following protective films B to D instead of the protective film A, it was carried out in the same manner as in Example 1 to produce a polarizing laminated film roll with a protective film, and a polarizing plate was produced using the roll (substrate membrane peeled off). The evaluation test of the image distortion similar to Example 1 was performed about the obtained polarizing plate. The results are shown in Table 1. In addition, in Examples 2-3 and the comparative example 1, the arithmetic average roughness Ra of the polarizer layer surface before lamination|stacking a protective film was 0.0456 micrometers similarly to Example 1.

Example 2: Protective film B (a self-adhesive polyethylene-based resin film with a thickness of 30 μm. The arithmetic average roughness Ra of the surface on the polarizer layer side according to the above-mentioned measurement procedure: 0.0690 μm),

Example 3: Protective film C (a protective film with a thickness of 25 μm comprising a base material containing a polypropylene resin and an adhesive layer laminated thereon. According to the above measurement procedure, the polarizer layer side (adhesive layer) The arithmetic average roughness of the surface Ra: 0.0621μm),

Comparative Example 1: Protective film D (a self-adhesive polyethylene resin film having a thickness of 30 μm. The arithmetic average roughness Ra of the surface on the polarizer layer side according to the above measurement procedure: 0.1559 μm).

In the production process of the polarizing plate, a film sheet was cut out from the polarizing laminated film obtained by peeling the protective film, and the surface of the polarizer layer (the side opposite to the base film) exposed by the peeling of the protective film was measured according to the above-mentioned measurement procedure. The arithmetic mean roughness Ra of the surface) was measured, and it was 0.0618 μm in Example 2, 0.0894 μm in Example 3, and 0.1072 μm in Comparative Example 1.

[Table 1]

[Symbol Description]

5 polarizer layer, 6 polyvinyl alcohol resin layer, 6' stretched polyvinyl alcohol resin layer, 7 protective film, 10 first thermoplastic resin film, 15 first adhesive layer, 20 second thermoplastic resin Film, 25 second adhesive layer, 30 substrate film, 30' stretched substrate film, 100 laminated film, 200 stretched laminated film, 300 polarizing laminated film, 400 polarizing laminated film with protective film , 500 first polarizing plate, 600 second polarizing plate, 700 third polarizing plate.

Claims (9)

1. A manufacturing method of a polarizing laminated film with a protective film, the manufacturing method comprising: A step of forming a polyvinyl alcohol-based resin layer on at least one surface of a base film to obtain a laminated film, a step of stretching the laminated film to obtain a stretched laminated film, A step of dyeing the polyvinyl alcohol-based resin layer of the stretched laminated film with a dichroic dye to form a polarizer layer, thereby obtaining a polarizing laminated film, and A step of laminating a protective film on the surface of the polarizer layer side of the polarizing laminated film to obtain a polarizing laminated film with a protective film, The arithmetic average roughness of the surface of the polarizer layer side of the protective film is 0.150 μm or less. 2. The manufacturing method according to claim 1, wherein, The protective film is stacked in contact with the surface of the polarizer layer. 3. The manufacturing method as claimed in claim 1 or 2, wherein, further comprising: A step of winding up the polarizing laminated film with a protective film to obtain a polarizing laminated film with a protective film roll. 4. A manufacturing method of polarizing plate, said manufacturing method comprising: A step of obtaining a polarizing laminated film with a protective film by the manufacturing method described in claim 1 or 2; A step of peeling the protective film from the polarizing laminated film with a protective film; a step of laminating a first thermoplastic resin film via a layer of an active energy ray-curable adhesive on the surface of the polarizing laminated film exposed by the step of peeling off the protective film on the side of the polarizer layer; and A step of curing the layer of the active energy ray-curable adhesive. 5. The manufacturing method according to claim 4, wherein, Between the step of obtaining the polarizing laminated film with a protective film and the step of peeling off the protective film, further comprising: winding the polarizing laminated film with a protective film to obtain a polarizing film with a protective film. The process of laminating film rolls, In the step of peeling the protective film, the protective film is peeled from the polarizing laminated film with a protective film unwound from the polarizing laminated film with a protective film roll. 6. The manufacturing method according to claim 4 or 5, wherein, After the step of curing the layer of the active energy ray-curable adhesive, a step of peeling the base film is further included. 7. A polarizing laminated film with a protective film, comprising: a substrate film, a polarizer layer comprising a polyvinyl alcohol-based resin, and a protective film in sequence, The arithmetic mean roughness of the surface of the protective film on the polarizer layer side is 0.150 μm or less. 8. The polarizing laminated film with a protective film according to claim 7, wherein the protective film is in contact with the surface of the polarizer layer. A polarizing laminated film roll with a protective film, which is a wound product of the polarizing laminated film with a protective film according to claim 7 or 8.