JP6370190B2 - Polarizing plate roll - Google Patents

Description

  The present invention relates to a polarizing plate roll formed by winding a long polarizing plate around a winding core.

  The polarizing plate is widely used in display devices such as a liquid crystal display device, especially in various mobile devices such as smartphones in recent years. As a polarizing plate, one having a configuration in which a protective film is bonded to one side or both sides of a polarizer is common, but with the development to mobile devices, the polarizer and protective film constituting the polarizing plate are made thinner. It is increasingly demanded.

  The production of the polarizing plate uses a long (band-shaped) raw material film as a raw material, and processes the raw material film while unwinding the raw material film from a roll in which the raw material film is wound around a winding core (winding core). It is common to use a so-called roll-to-roll method in which a long (strip-shaped) polarizing plate is applied and the obtained polarizing plate is wound around a core to form a roll. Accordingly, the polarizing plate is usually obtained as a polarizing plate roll obtained by winding a long polarizing plate around a core (for example, Patent Document 1).

JP 2013-29754 A

  As described above, the polarizing plate is generally manufactured in the form of a polarizing plate roll. For example, when the film length of the polarizing plate is 2000 m and the diameter of the core is 150 mmφ, the number of windings of the polarizing plate reaches about 4000 times.

  The polarizing plate manufactured as a polarizing plate roll is used for subsequent processes such as further laminating another film or forming a coating layer, or while being transported to a supply destination. It is often held in a roll for a certain continuous period.

However, the polarizing plate unwound after being held in a roll state for a certain continuous period has a problem that it is easily accompanied by a defect called “winding streak defect”. This problem becomes more prominent as the polarizer and the protective film constituting the polarizing plate are thinner. Referring to FIG. 7, the “winding streak defect” is a difference in height generated between the winding start end of the polarizing plate and the outer periphery of the core, that is, the polarizing plate to be wound is pressed against the stepped portion. Is a streak-like dent defect extending in the width direction of the polarizing plate. When winding the polarizing plate after fixing the winding start end of the polarizing plate to the core using a fixing member such as a double-sided tape, winding streak defects are particularly noticeable. As shown in FIG. 7, the winding streak defects are pressed against the corners of the defect K ₁ (winding start end of the polarizing plate from a corner portion of the winding start end of the polarizer (short side angle end) In the case where the fixing member is used, a defect K ₂ derived from a corner portion of the fixing member (defect generated by being pressed against the corner portion of the fixing member) is further included.

  Winding streak defects are strongly generated in the polarizing plate inside the polarizing plate roll (initial polarizing plate at the start of winding), and become weaker toward the outer side of the polarizing plate roll. can occur over m. When a polarizing plate containing winding streak defects is applied to an image display device such as a liquid crystal display device, the visibility may be lowered. If the polarizing plate portion having the defect is removed as a defective product, the product of the polarizing plate The yield is greatly reduced.

  Therefore, the present invention is a polarizing plate roll formed by winding a polarizing plate around a winding core, and can suppress a “winding streak defect” that can be confirmed when the polarizing plate is unwound from the roll. The purpose is to provide a role.

The present invention provides the following polarizing plate roll.
[1] A core including a first convex portion and a second convex portion extending in the circumferential direction on the outer peripheral surface, and a polarizing plate wound around the core,
The polarizing plate comprises a polarizer and a protective film laminated on at least one surface thereof,
The polarizing plate is wound around the core such that one end region in the width direction of the protective film is located on the first convex portion and the other end region is located on the second convex portion. A polarizing roll that is rotated.

  [2] In the polarizing plate, one end portion in the width direction of the polarizer is positioned on the inner side of the inner end portion of the first convex portion, and the other end portion is an inner end portion of the second convex portion. The polarizing plate roll according to [1], wherein the polarizing plate roll is wound around the core so as to be positioned on the inner side.

  [3] The polarizing plate roll according to [1] or [2], wherein a winding start end of the polarizing plate is fixed to the outer peripheral surface using a fixing member.

  [4] The polarizing plate roll according to any one of [1] to [3], wherein the heights of the first convex portion and the second convex portion are each 50 μm or more.

  [5] The polarizing plate roll according to any one of [1] to [4], wherein the first convex portion and the second convex portion are formed of a resin film attached to the outer peripheral surface.

  ADVANTAGE OF THE INVENTION According to this invention, the polarizing plate roll which can suppress a winding stripe defect can be provided. By suppressing the winding streak defect, the product quality and product yield of the polarizing plate can be improved.

It is a schematic diagram which shows an example of the core with a convex part used for the polarizing plate roll which concerns on this invention. It is sectional drawing in the part which has the 1st convex part of the core with a convex part shown by FIG. It is sectional drawing which shows typically an example of the positional relationship regarding the width direction between the convex part of the core with a convex part, and the polarizing plate wound. It is sectional drawing which shows typically another example of the positional relationship regarding the width direction between the convex part of the core with a convex part, and the polarizing plate wound. It is sectional drawing which shows another example of the core with a convex part. It is the schematic which shows a mode that the winding start end part of a polarizing plate is fixed to a core with a convex part using a fixing member. It is the schematic for demonstrating a winding stripe defect.

As shown in FIG. 1 and FIG. 2, the polarizing plate roll according to the present invention has a convex winding having a first convex portion 10 a and a second convex portion 10 b extending in the circumferential direction as a winding core on the outer peripheral surface. This is a roll-type polarizing plate in which a core 10 is used and a long polarizing plate is wound around the core 10. In the present invention, the above-mentioned “
In order to suppress the occurrence of “winding streak defects”, one end region in the width direction of the protective film constituting the polarizing plate is positioned on the first convex portion 10a and the other end region is the second. It winds around the core 10 with a convex part so that it may be located on the convex part 10b. The positional relationship in the width direction between the convex portions 10a and 10b of the core with convex portion 10 and the polarizing plate to be wound will be described in detail in the section (3) below.

(1) Core with convex part The core 10 with convex part can have the same shape as a conventionally well-known core except having the 1st convex part 10a and the 2nd convex part 10b, These The main body portion of the core excluding the convex portion can be, for example, a columnar shape or a cylindrical shape. The material is not particularly limited, and a metal, an alloy, or a resin (such as a thermoplastic resin) can be used. The length in the width direction (rotation axis direction) of the core 10 with the convex portion is approximately the same as or longer than the width of the polarizing plate to be wound. In the case where the core 10 with a convex portion is columnar or cylindrical, the diameter thereof may be a general diameter of the core, for example, about 100 to 200 mmφ.

  The installation position of the 1st convex part 10a and the 2nd convex part 10b provided in the outer peripheral surface of the core 10 with a convex part is dependent on the width | variety of the polarizing plate wound. Specifically, the first convex portion 10a and the second convex portion 10b are positions different from each other on the outer peripheral surface, and one end region in the width direction of the protective film constituting the polarizing plate is the first. It is located on the convex portion 10a, and is installed so that the other end region is located on the second convex portion 10b. As FIG. 1 shows, the 1st convex part 10a and the 2nd convex part 10b are the edge part area | region (an edge part is included) or edge part of the width direction (rotating-axis direction) of the core 10 with a convex part normally. It is provided near.

  The 1st convex part 10a and the 2nd convex part 10b are provided in the outer peripheral surface of the core 10 with a convex part so that it may extend in the circumferential direction of the core 10 with a convex part, Preferably the circumference | surroundings of the core 10 with a convex part are provided. It extends in parallel to the direction (perpendicular to the rotational axis direction of the core 10 with protrusions). As shown in FIG. 2, the first convex portion 10 a and the second convex portion 10 b are preferably strip-shaped, and are provided in an annular shape over the entire circumference or approximately the entire circumference of the outer peripheral surface of the core 10 with the convex portion. It is preferable.

  The 1st convex part 10a and the 2nd convex part 10b may be shape | molded integrally with the main-body part of the core 10 with a convex part, or may be formed using another member different from this main-body part. Good. As a method of forming a convex part using another member, the 1st convex part 10a and the 2nd convex part 10b are provided in the outer peripheral surface of the columnar or cylindrical core as a main-body part of the core 10 with a convex part. The method of sticking the resin film to form (for example, a film tape from a thermoplastic resin) can be mentioned. This resin film may have an adhesive layer on one side for sticking to the outer peripheral surface of the core. According to the method of sticking the resin film using an adhesive, it is possible to reattach the film, so that the position adjustment or position change of the convex portion is facilitated. The method of forming the convex portion by sticking the resin film is advantageous in terms of the manufacturing cost of the convex core 10 and the simplicity of manufacturing, and the convex core 10 having sufficient strength is provided. Can be obtained. The resin film may be attached to the outer peripheral surface of the core using an adhesive.

(2) Polarizing plate The polarizing plate wound around the convex core 10 includes a polarizer and a protective film laminated on at least one surface thereof. The protective film may be laminated | stacked on both surfaces of the polarizer. The protective film is usually bonded to the polarizer via an adhesive layer. As the adhesive, an active energy ray-curable adhesive such as an ultraviolet curable adhesive or a water-based adhesive such as a polyvinyl alcohol resin aqueous solution can be used. The total thickness of the polarizing plate is generally about 30 to 300 μm.

  As the polarizer, one obtained by adsorbing and orienting a dichroic dye on a uniaxially stretched polyvinyl alcohol resin can be preferably used. As the dichroic dye, iodine or a dichroic dye can be used. As the polyvinyl alcohol resin constituting the polarizer, a saponified polyvinyl acetate resin can be used. Examples of the polyvinyl acetate-based resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids and acrylamides having ammonium groups.

  The saponification degree of the polyvinyl alcohol resin is usually about 85 to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol resin may be modified, and for example, polyvinyl formal and polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol resin is usually about 1000 to 10000, preferably about 1500 to 5000.

  The polarizer is a step of uniaxially stretching (typically, longitudinally uniaxially stretching in the longitudinal direction of the film) the original film made of the polyvinyl alcohol resin, and the polyvinyl alcohol resin film is dyed with a dichroic dye. It can be produced by a method including a step of adsorbing a chromatic dye, a step of treating a polyvinyl alcohol resin film adsorbed with a dichroic dye with a boric acid aqueous solution, and a step of washing with water after the treatment with the boric acid aqueous solution. You may provide the swelling process which performs the immersion process to water before a dyeing | staining process.

  Uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before, simultaneously with, or after dyeing the dichroic dye. When uniaxial stretching is performed after dyeing, this uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. Moreover, you may uniaxially stretch in these several steps.

  The thickness of the polarizer (average thickness over the entire width) is, for example, 40 μm or less, preferably 25 μm or less, more preferably 20 μm or less. Especially in the polarizing plate for mobile devices, the viewpoint of thinning the polarizing plate To 10 μm or less. The thickness of the polarizer is usually 2 μm or more. Even when such a thin film polarizer is used, the present invention can effectively suppress winding streak defects.

  The protective film to be bonded to the polarizer is a light-transmitting (preferably optically transparent) thermoplastic resin such as a chain polyolefin resin (polypropylene resin, etc.), a cyclic polyolefin resin (norbornene-based). Polyolefin resins such as resin); cellulose ester resins such as cellulose triacetate and cellulose diacetate; polyester resins; polycarbonate resins; (meth) acrylic resins; polystyrene resins; or a mixture or copolymer thereof. It can be a film made of an object or the like. When a protective film is bonded on both surfaces of a polarizer, these may be protective films made of the same kind of resin or may be protective films made of different kinds of resins.

  The protective film can also be a protective film having an optical function such as a retardation film and a brightness enhancement film. For example, a retardation film provided with an arbitrary retardation value by stretching a film made of the thermoplastic resin (uniaxial stretching or biaxial stretching) or by forming a liquid crystal layer or the like on the film. It can be.

  Examples of the chain polyolefin-based resin include a homopolymer of a chain olefin such as a polyethylene resin and a polypropylene resin, and a copolymer composed of two or more chain olefins.

  Cyclic polyolefin resin is a general term for resins that are polymerized using a cyclic olefin as a polymerization unit. Specific examples of cyclic polyolefin resins include ring-opening (co) polymers of cyclic olefins, addition polymers of cyclic olefins, copolymers of cyclic olefins and chain olefins such as ethylene and propylene (typically Are random copolymers), graft polymers obtained by modifying them with unsaturated carboxylic acids or derivatives thereof, and hydrides thereof. Among these, norbornene resins using norbornene monomers such as norbornene and polycyclic norbornene monomers as cyclic olefins are preferably used.

  The cellulose ester resin is an ester of cellulose and a fatty acid. Specific examples of the cellulose ester resin include cellulose triacetate, cellulose diacetate, cellulose tripropionate, and cellulose dipropionate. Moreover, these copolymers and those in which a part of the hydroxyl group is modified with other substituents can also be used. Among these, cellulose triacetate (triacetyl cellulose: TAC) is particularly preferable.

  The polyester-based resin is a resin having an ester bond other than the cellulose ester-based resin, and generally includes a polycondensate of a polyvalent carboxylic acid or a derivative thereof and a polyhydric alcohol. As the polyvalent carboxylic acid or a derivative thereof, a dicarboxylic acid or a derivative thereof can be used, and examples thereof include terephthalic acid, isophthalic acid, dimethyl terephthalate, and dimethyl naphthalenedicarboxylate. A diol can be used as the polyhydric alcohol, and examples thereof include ethylene glycol, propanediol, butanediol, neopentyl glycol, and cyclohexanedimethanol.

  Specific examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexanedimethyl terephthalate, and polycyclohexanedimethyl naphthalate.

  The polycarbonate resin is composed of a polymer in which monomer units are bonded via a carbonate group. The polycarbonate-based resin may be a resin called a modified polycarbonate having a modified polymer skeleton, a copolymer polycarbonate, or the like.

The (meth) acrylic resin is a resin containing a compound having a (meth) acryloyl group as a main constituent monomer. Specific examples of (meth) acrylic resins include, for example, poly (meth) acrylic acid esters such as polymethyl methacrylate; methyl methacrylate- (meth) acrylic acid copolymer; methyl methacrylate- (meth) acrylic acid Ester copolymer; methyl methacrylate-acrylic ester- (meth) acrylic acid copolymer; (meth) methyl acrylate-styrene copolymer (MS resin etc.); methyl methacrylate and alicyclic hydrocarbon group And a copolymer (for example, methyl methacrylate-cyclohexyl methacrylate copolymer, methyl methacrylate- (meth) acrylate norbornyl copolymer). Preferably, a polymer based on a poly (meth) acrylic acid C _1-6 alkyl ester such as poly (meth) acrylic acid methyl is used, and more preferably methyl methacrylate is the main component (50-100). % Methyl methacrylate resin is used.

  The thickness of the protective film is preferably 90 μm or less, more preferably 50 μm or less, and still more preferably 30 μm or less, from the viewpoint of thinning the polarizing plate. The thickness of the protective film is usually 5 μm or more from the viewpoint of strength and handleability. Even when such a thin protective film is used, according to the present invention, winding streak defects can be effectively suppressed.

  The polarizing plate may include a film or layer other than the protective film. Specific examples of films and layers other than the protective film include: an adhesive layer; a separate film that protects the outer surface of the adhesive layer (release film); a protective film that protects the surface of the protective film (surface protective film); Surface treatment layer (coating layer) for imparting functions; including various optical functional films.

  As the pressure-sensitive adhesive used for the pressure-sensitive adhesive layer, a conventionally known appropriate pressure-sensitive adhesive can be used. For example, an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, a polyester-based pressure-sensitive adhesive, a polyamide-based pressure-sensitive adhesive, Examples include polyether-based pressure-sensitive adhesives, fluorine-based pressure-sensitive adhesives, and rubber-based pressure-sensitive adhesives. Among these, an acrylic pressure-sensitive adhesive is preferably used from the viewpoints of transparency, adhesive strength, reliability, reworkability, and the like. Generally the thickness of an adhesive layer can be 1-40 micrometers (for example, 3-25 micrometers).

  The constituent material of the separate film can be a polyethylene resin such as polyethylene, a polypropylene resin such as polypropylene, a polyester resin such as polyethylene terephthalate, and the like. Among these, a stretched film of polyethylene terephthalate is preferable.

  Examples of the constituent material of the protective film include polyethylene resins such as polyethylene, polypropylene resins such as polypropylene, and polyester resins such as polyethylene terephthalate. Among them, from the viewpoint of moisture permeability and mechanical strength A stretched film of polyethylene terephthalate is preferred.

  Examples of the surface treatment layer include a hard coat layer, an antiglare layer, an antireflection layer, an antistatic layer, and an antifouling layer.

  As the optical functional film, a reflective polarizing film that transmits a certain kind of polarized light and reflects polarized light that shows the opposite property; a film with an antiglare function having an uneven shape on the surface; a film with a surface antireflection function; Examples thereof include a reflective film having a reflective function on the surface; a transflective film having both a reflective function and a transmissive function; and a viewing angle compensation film.

  Although the width | variety of the polarizing plate wound by the core 10 with a convex part is not restrict | limited in particular, Usually, it is about 300-2500 mm, More typically, it is about 500-2000 mm. Further, the length of the polarizing plate is not particularly limited, but is usually about several hundred m to 3000 m (for example, about 2000 m), and more typically about 1500 to 2500 m. Although the width | variety of a polarizer and the width | variety of the protective film bonded to this may be the same or different, the width | variety of a protective film is made larger and the width direction both ends (end surface) of a protective film are It is common to paste a protective film so that it may be located outside both ends (both end surfaces) in the width direction of the polarizer.

(3) Positional relationship regarding width direction between convex part of winding core with convex part and polarizing plate wound FIG. 3 shows the convex part of the core 10 with convex part and the polarizing plate 20 to be wound. It is sectional drawing which shows typically an example of the positional relationship regarding the width direction between. In FIG. 3, the case where the polarizing plate 20 comprised from the polarizer 21 and the 1st protective film 22 bonded on the one surface and the 2nd protective film 23 bonded on the other surface is used as an example. Although shown, the layer configuration of the polarizing plate is not limited to this as described above. FIG. 3 shows only the first convex portion 10a of the core 10 with convex portions, but the contents described below are similarly applied to the positional relationship with the second convex portion 10b.

In the polarizing plate roll of the present invention, the polarizing plate 20 has one end region in the width direction of the protective film located on the first convex portion 10a and is not shown in FIG. It winds around the core 10 with a convex part so that it may be located on the 2 convex part 10b. When the protective films (first and second protective films 22 and 23) are provided on both surfaces of the polarizer 21 as in the example of FIG. 3, both protective films are wound so as to satisfy the above positional relationship. It is preferable.

That one end region of the protective film is located on the first convex portion 10a means that the end portion (end surface, T ₁ in FIG. 3) of the protective film is the first convex portion 10a as in the example shown in FIG. In addition to the case where it is positioned above, the end T ₁ of the protective film is positioned outside the outer end T ₂ of the first convex portion 10a, but the end region in the vicinity of the end T ₁ of the protective film is This includes the case where it is placed on the first convex portion 10a. The end T ₁ near the end region of the protective film, for each end, a region of up to 15% of the width of the polarizing plate. Thereby, the winding streak defect suppression effect can be obtained. The end T ₁ of the protective film being positioned on the first convex portion 10a means that the end T ₁ is positioned between the outer end T ₂ and the inner end T ₃ of the first convex portion 10a ( Including the case where T ₁ matches T ₂ or T ₃ ). When the end T ₁ of the protective film is located on the inner side of the inner end (end face) T _{3 of} the first convex portion 10a, it is difficult to obtain a winding streak defect suppressing effect.

In obtaining the winding streak defect suppressing effect, as shown in FIG. 3, in the polarizing plate 20, the end portion T ₄ in the width direction of the polarizer 21 is positioned inside the inner end portion T ₃ of the first convex portion 10a. As shown in FIG. 4, the end T ₄ of the polarizer 21 is positioned on the first convex portion 10a, that is, the polarizer. The convex portion so that the end portion T _{4 of} 21 is located between the outer end portion T ₂ and the inner end portion T ₃ of the first convex portion 10a (including the case where T ₁ coincides with T ₂ or T ₃ ). It may be wound around the attached core 10. The former is preferred.

Referring to FIGS. 3 and 4, located on the first projection 10a (riding) width W ₂ of the end region of the protective film (the protective film overlaps the width of the first convex portion 10a) is It is preferably 5 mm or more, and more preferably 10 mm or more. If the overlap width W ₂ is too small, it is difficult to obtain a sufficient winding streak defect suppressing effect. The upper limit of the overlap width W ₂ is not particularly limited, but can be about 30 mm, for example. The width W ₁ of the first convex portion 10a is preferably 5 mm or more so that the preferable overlapping width W ₂ is obtained. The upper limit of the width W ₁ is not particularly limited, and is 100 mm, for example.

In order to obtain the winding streak defect suppressing effect more effectively, the height H of the first convex portion 10a is preferably 50 μm or more. The upper limit of the height H can be 1500 μm (for example, 1000 μm). For example, when forming a convex part by sticking of a resin film, in order to enlarge height H, as shown in FIG. Figure 5 is an example of forming a first convex portion 10a by superimposing winding the second resin film t ₂ on the first resin film t _1. When a plurality of layers of resin films are wound, it is preferable to shift the seams without matching them as shown in FIG. This is because the connected seam can cause a winding streak defect.

As shown in FIG. 4, when the end portion T ₄ of the polarizer 21 is located on the first convex portion 10a in order to obtain a winding streak defect suppression effect more effectively, the end portion T ₄ is the as compared with the case located inside the inner end portion T ₃ of the first convex portion 10a, it is preferable that the height H of the first protrusion 10a is lower. That is, the thickness of the polarizer 21 located on the first convex portion 10a increases the height difference (step portion) generated between the winding start end of the polarizing plate and the outer peripheral surface of the core that causes winding streak defects. Therefore, it is advantageous for suppressing the winding streak defect that the height H of the first convex portion 10a is lower, for example, 400 μm or less, and further 200 μm or less.

On the other hand, when the end portion T ₄ of the polarizer 21 is located on the inner side of the inner end portion T ₃ of the first convex portion 10a, the first convex portion is obtained in order to more effectively obtain the winding streak defect suppressing effect. It is preferable to make the height H of 10a relatively high, for example, 150 μm or more, more preferably 300 μm or more.

As described above, the width of the protective film is made larger, and the protective film is generally pasted so that both ends in the width direction of the protective film are located outside the both ends in the width direction of the polarizer. 3, the protrusion width W _{3 of} the protective film (the first protective film 22 and the second protective film 23) (from the end T ₁ of the protective films 22 and 23 to the end T ₄ of the polarizer 21). The distance) can be about 1 to 100 mm (for example, about 5 to 60 mm).

(4) Fixing the winding start end of the polarizing plate to the core with the convex portion The polarizing plate 20 is wound up by rotating the core 10 with the convex portion around its rotation axis. At this time, as shown in FIG. 6, before starting winding, the fixing member 30 is used [FIG. 6 (a)], and the winding start end (longitudinal direction start end) of the polarizing plate 20 is provided with a convex portion. It is preferable to fix to the outer peripheral surface of the core 10 (FIG. 6B). Since the polarizing plate 20 can be easily fixed, a double-sided tape can be preferably used as the fixing member 30. For example, a fixing member 30 that is a double-sided tape is attached to the outer peripheral surface of the core 10 with a convex portion parallel to the rotation axis of the core 10 with a convex portion, and the winding start end of the polarizing plate 20 is polarized on the fixing member 30. It sticks so that the short side direction of the board 20 may become parallel to the rotating shaft of the core 10 with a convex part. By fixing the winding start end of the polarizing plate 20 to the core 10 with the convex portion, the winding of the polarizing plate 20 in the initial stage can be smoothly performed. When the winding start end of the polarizing plate 20 is fixed to the core 10 with the convex portion using the fixing member, the height difference (step) between the winding start end of the polarizing plate 20 and the outer peripheral surface of the core 10 with the convex portion. However, according to the present invention, the winding streak defect can be effectively suppressed even in such a case.

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

<Comparative Example 1>
First protective film made of triacetylcellulose (TAC) [thickness 40 μm] / adhesive layer / polarizer obtained by adsorbing and orienting a dichroic dye to a longitudinally uniaxially stretched polyvinyl alcohol resin film / thickness 28 μm / adhesion A long polarizing plate having a layer structure of a protective film [thickness 40 μm] / protective film [thickness 62 μm] made of an agent layer / TAC and a stretched polyethylene phthalate is continuously produced by a roll-to-roll method. Then, it was wound around a cylindrical core (no protrusion) to obtain a polarizing plate roll. The specific conditions for producing the polarizing plate roll are as follows. In addition, the winding start end (longitudinal direction start end) of the polarizing plate was fixed to the outer peripheral surface of the core using a double-sided tape having a thickness of 176 μm.

[1] Cylindrical core (no protrusion)
・ Material: FRP (fiber reinforced plastic),
・ Width direction (rotating axis direction) length: 1480 mm,
・ Diameter: 167mmφ,
[2] Polarizing plate Width of protective film: 1330 mm,
-Polarizer width: 1270 mm,
- Figure 3 in W _3: 30 mm (both ends),
-Polarizing plate length: about 2000m
-Tension at the time of winding a polarizing plate: 60N.

<Comparative Examples 2-4>
The tension at the time of winding the polarizing plate is 100 N (Comparative Example 2), 150 N (Comparative Example 3),
A polarizing plate roll was produced in the same manner as in Comparative Example 1 except that 250N (Comparative Example 4) was used.

<Example 1>
A polarizing plate roll was produced in the same manner as in Comparative Example 1 except that the same core with projections as in FIG. 1 was used and the specific conditions for producing the polarizing plate roll were as follows. As for a polarizing plate, one edge part area | region in the width direction of the protective film bonded on both surfaces of the polarizer is located on a 1st convex part, and the other edge part area | region is located on a 2nd convex part. I wound it. However, as shown in FIG. 3, the end T ₄ of the polarizer 21 is positioned inside the inner end T _{3 of} the first and second convex portions 10 a and 10 b (the polarizer and the convex portion). Wound it so that it would not overlap. As shown in FIG. 5, the first and second convex portions of the core with convex portions are adhered to the outer peripheral surface of the core main body portion over a substantially entire circumference with a fixed width resin film tape having an adhesive layer on one side. Further, a resin film tape having the same width and having an adhesive layer on one side was attached to the outer peripheral surface thereof by shifting the seam by about 15 mm and pasting the entire circumference.

[1] Convex core (main body part: cylindrical)
・ Material: FRP (fiber reinforced plastic),
・ Width direction (rotating axis direction) length: 1480 mm,
・ Diameter of body part: 167mmφ,
The width of the first and second convex portions (W ₁ in FIG. 3): 10 mm,
-Height of 1st and 2nd convex part (H in FIG. 3): 360 micrometers,
[2] Polarizing plate Width of protective film: 1330 mm,
-Polarizer width: 1270 mm,
-The protruding width of the protective film (W ₃ in FIG. ₃ ): 30 mm (both ends),
-Polarizing plate length: about 2000m
・ Tension during winding of polarizing plate: 60N,
[3] the overlapping width of the positional relationship, both sides of the protective film and the first and second convex portions of the polarizing plate and the lug core (W ₂ in FIG. 3): 10 mm,
The overlapping width between the polarizer and the first and second convex portions: 0 mm.

<Examples 2-3>
A polarizing plate roll was produced in the same manner as in Example 1, except that the tension at the time of winding the polarizing plate was 150 N (Example 2) and 250 N (Example 3), respectively.

<Example 4>
Example 1 except that the tension at the time of winding the polarizing plate was 150 N, the resin film tape was wound on three layers, and the height of the first and second protrusions (H in FIG. 3) was 540 μm. Thus, a polarizing plate roll was produced.

<Example 5>
A polarizing plate roll was produced in the same manner as in Comparative Example 1 except that the same core with projections as in FIG. 1 was used and the specific conditions for producing the polarizing plate roll were as follows. As for a polarizing plate, one edge part area | region in the width direction of the protective film bonded on both surfaces of the polarizer is located on a 1st convex part, and the other edge part area | region is located on a 2nd convex part. I wound it. In this embodiment, as shown in FIG. 4, one end T ₄ in the width direction of the polarizer 21 is located on the first convex portion 10a, and the other end T ₄ is on the second convex portion 10b. Wound to be located in As for the 1st and 2nd convex part of the core with a convex part, the fixed-width resin film tape which has an adhesive layer on one side is stuck on the outer peripheral surface of a core main-body part over substantially the whole circumference like FIG. Formed by.

[1] Convex core (main body part: cylindrical)
・ Material: FRP (fiber reinforced plastic),
・ Width direction (rotating axis direction) length: 1480 mm,
・ Diameter of body part: 167mmφ,
The width of the first and second convex portions (W ₁ in FIG. 4): 10 mm,
-Height of 1st and 2nd convex part (H in FIG. 4): 360 micrometers,
[2] Polarizing plate Width of protective film: 1330 mm,
-Polarizer width: 1270 mm,
-The protruding width of the protective film (W ₃ in FIG. ₃ ): 30 mm (both ends),
-Polarizing plate length: about 2000m
・ Tension during winding of polarizing plate: 250 N,
[3] the overlapping width of the positional relationship, both sides of the protective film and the first and second convex portions of the polarizing plate and the lug core (W ₂ in FIG. 4): 10 mm,
The overlapping width between the polarizer and the first and second convex portions (distance from the end T ₄ in FIG. ₄ to the inner end T ₃ of the convex portion): 10 mm.

<Example 6>
A polarizing plate roll was produced in the same manner as in Example 5 except that the height of the first and second protrusions (H in FIG. 4) was 180 μm.

  Table 1 shows the main production conditions of the polarizing plate rolls in Examples 1 to 6 and Comparative Examples 1 to 4. The produced polarizing plate roll was stored for 15 days in an environment of 25 ° C. and 50% RH, and then the polarizing plate roll was unwound and the generation length of winding streak defects from the beginning of the polarizing plate was measured. The results are shown in Table 1.

  DESCRIPTION OF SYMBOLS 10 Core with convex part, 10a 1st convex part, 10b 2nd convex part, 20 Polarizing plate, 21 Polarizer, 22 1st protective film, 23 2nd protective film, 30 Fixing member.

Claims (4)

Including a core provided with a first protrusion and a second protrusion extending in the circumferential direction on the outer peripheral surface, and a polarizing plate wound around the core,
The polarizing plate comprises a polarizer and a protective film laminated on at least one surface thereof,
The polarizing plate is wound around the core such that one end region in the width direction of the protective film is located on the first convex portion and the other end region is located on the second convex portion. And one end in the width direction of the polarizer is positioned inside the inner end of the first convex portion, and the other end is inside the inner end of the second convex portion. wherein Ru is wound on the winding core, the polarizing plate roll to be located. The polarizing plate roll according to claim 1, wherein a winding start end of the polarizing plate is fixed to the outer peripheral surface using a fixing member. The polarizing plate roll according to claim 1 or 2 , wherein each of the first convex portion and the second convex portion has a height of 50 µm or more. The said 1st convex part and the said 2nd convex part are polarizing plate rolls of any one of Claims 1-3 comprised with the resin film affixed on the said outer peripheral surface.

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