JP2015203828A - Stretched laminate and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polarization film that is excellent in the uniformity of optical properties (for example, degree of polarization) even when it is formed wide, and a stretched laminate that can be applied for making the polarization film.SOLUTION: This invention provides a long stretched laminate 10 comprising a polyester resin base material 11 and a polyvinyl alcohol resin layer 12 formed on the base material, wherein the stretched laminate has a width of 1500 mm-2700 mm, and variations in the orientation angles of the polyvinyl alcohol resin layer in width direction are 4.0° or less.

Description

  The present invention relates to a stretched laminate and a method for producing the stretched laminate.

  A liquid crystal display device, which is a typical image display device, has polarizing films disposed on both sides of a liquid crystal cell due to the image forming method. In recent years, since a thin polarizing film has been desired, for example, a laminate of a specific thermoplastic resin substrate and a polyvinyl alcohol-based resin layer is stretched in the air and further stretched in a boric acid aqueous solution. A method for obtaining a polarizing film has been proposed (for example, Patent Document 1). According to such a method, the laminate can be stretched at a high magnification, and a polarizing film having excellent optical properties can be obtained.

  However, when a polarizing film having a desired size is punched out from the long polarizing film obtained by the above method, there may be a difference in optical characteristics (for example, the degree of polarization) of the polarizing film to be obtained. Such a problem of difference in optical characteristics is particularly likely to occur when punching from a wide polarizing film.

JP 2012-73580 A

  The present invention has been made to solve the above problems, and its main purpose is to apply a polarizing film excellent in uniformity of optical characteristics (for example, the degree of polarization) even when it is wide, and the production of the polarizing film. It is to provide a stretch laminate that can be made.

The present inventors have intensively studied in order to solve the above problems. As a result, bowing occurs when the long laminate is stretched in the air, and the orientation of the polyvinyl alcohol-based resin layer becomes nonuniform. Due to the non-uniformity of the orientation of the resin layer, the axial accuracy of the obtained long polarizing film is also non-uniform, and as a result, the optical characteristics of the polarizing film (for example, the degree of polarization) ) Was found to be different. Furthermore, it has been found that a polarizing film having excellent optical property uniformity can be obtained by controlling the variation in the orientation angle of the polyvinyl alcohol resin layer within a specific range when the laminate is stretched in the air.
That is, the stretched laminate of the present invention is a long stretched laminate including a polyester resin substrate and a polyvinyl alcohol-based resin layer formed on the substrate, and the width of the stretched laminate. However, the variation of the orientation angle in the width direction of the polyvinyl alcohol-based resin layer is 4.0 ° or less.
In one embodiment, the birefringence (Δn) in the front direction of the polyvinyl alcohol-based resin layer satisfies a relationship of 5 × 10 ⁻³ <Δn <30 × 10 ⁻³ .
In one embodiment, the polyvinyl alcohol-based resin layer has a thickness of 15 μm or less.
According to another situation of this invention, the method of manufacturing the said extending | stretching laminated body is provided. The method includes a laminate production step in which a polyvinyl alcohol resin layer is formed on a polyester resin substrate to produce a long laminate, and the laminate is stretched in the air while being conveyed in the longitudinal direction. A stretching step for producing a stretched laminate.
In one embodiment, the stretching step includes a stretching step (1) for stretching the laminated body at a free end and a stretching step (2) for stretching the laminated body at a fixed end.
In one embodiment, ratio [(1) / (2)] of draw ratio in extending process (1) and extending process (2) is 1.2 or less.
In one embodiment, the total stretch ratio in the stretching step is 1.8 to 3.2 times, and the width of the stretched laminate by ideal shrinkage calculated from the total stretch ratio is W _i. When the width of the obtained stretched laminate is W _r , the relationship 1 ≦ W _r / W _i ≦ 1.1 is satisfied.
According to still another aspect of the present invention, a polarizing film is provided. The polarizing film is a polarizing film produced using the stretched laminate.

  According to the present invention, when the laminate is stretched in the air, by controlling the variation in the orientation angle of the polyvinyl alcohol resin layer within a specific range, the optical characteristics (for example, the degree of polarization) are uniform even when the width is wide. A long polarizing film having excellent properties can be obtained.

It is a fragmentary sectional view of the extending | stretching laminated body by preferable embodiment of this invention. It is the schematic which shows an example of the extending process (1) of this invention. It is the schematic which shows an example of the extending process (2) of this invention. It is the schematic which shows an example of the manufacturing method of the polarizing film of this invention. It is a graph which shows the relationship between the dispersion | variation in the orientation angle in a PVA-type resin layer, and the amount of axial deviation in a polarizing film. It is a graph which shows the relationship between an axial deviation | shift amount and a polarization degree.

A. Stretched laminate A-1. Overall Configuration The stretched laminate of the present invention is a long stretched laminate, which is a polyester-based resin substrate and a polyvinyl alcohol-based resin (hereinafter referred to as “PVA-based resin”) layer formed on the substrate. Including. FIG. 1 is a schematic cross-sectional view of a stretched laminate according to one embodiment of the present invention. The stretched laminate 10 includes a polyester resin substrate 11 and a PVA resin layer 12. Although not shown, any appropriate functional layer may be formed on the side of the polyester resin substrate 11 where the PVA resin layer 12 is not formed.

  The width of the stretched laminate is 1500 mm to 2700 mm, preferably 1800 mm to 2300 mm. When the width is 1500 mm or more, a polarizing film having a wide width, good optical characteristics and excellent uniformity can be suitably obtained. On the other hand, if the width exceeds 2700 mm, there may be a problem in workability during conveyance.

A-2. Resin Substrate As a material for forming the polyester resin substrate, an amorphous (non-crystallized) polyethylene terephthalate resin is preferably used. Among these, amorphous (hard to crystallize) polyethylene terephthalate resin is particularly preferably used. Specific examples of the amorphous polyethylene terephthalate resin include a copolymer further containing isophthalic acid as a dicarboxylic acid, and a copolymer further containing cyclohexanedimethanol as a glycol.

  The glass transition temperature (Tg) of the resin base material is preferably 170 ° C. or lower, more preferably 120 ° C. or lower, and further preferably 80 ° C. or lower. On the other hand, the glass transition temperature of the resin substrate is preferably 60 ° C. or higher. In addition, a glass transition temperature (Tg) is a value calculated | required according to JISK7121.

  The thickness of the resin base material in the stretched laminate is preferably 10 μm to 200 μm, more preferably 20 μm to 150 μm.

A-3. PVA resin layer The PVA resin layer is excellent in axial accuracy in the width direction. The variation in the orientation angle in the width direction of the PVA resin layer (difference between the maximum value and the minimum value of the orientation angle) is 4.0 ° or less, preferably 3.5 ° or less, more preferably 3.0 °. It is as follows. By increasing the axial accuracy of the PVA resin layer in the stretched laminate, a long polarizing film having excellent axial accuracy can be obtained. As a result, when the obtained long polarizing film is punched to obtain a single-wafer polarizing film, it is possible to prevent a difference in optical characteristics between the polarizing films.

The birefringence (Δn) in the front direction of the PVA resin layer preferably satisfies the relationship of 5 × 10 ⁻³ <Δn <30 × 10 ⁻³ , and more preferably 15 × 10 ⁻³ <Δn <25 × 10. ^-3 is satisfied. When the birefringence in the front direction of the PVA resin layer in the stretched laminate satisfies the above relationship, a polarizing film having excellent optical characteristics can be obtained. One of the characteristics of the stretched laminate of the present invention is that the orientation angle variation in the width direction of the PVA resin layer is small while being stretched to such an extent that birefringence is obtained. The birefringence (Δn) is a value determined by the formula: Δn = nx−ny. Here, nx is the refractive index in the direction in which the in-plane refractive index is maximum (that is, the slow axis direction), and ny is the refractive index in the direction perpendicular to the slow axis in the plane.

  Arbitrary appropriate resin may be employ | adopted as PVA-type resin which forms the said PVA-type resin layer. Examples thereof include polyvinyl alcohol and ethylene-vinyl alcohol copolymer. Polyvinyl alcohol is obtained by saponifying polyvinyl acetate. An ethylene-vinyl alcohol copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer. The degree of saponification of the PVA resin is usually 85 mol% to 100 mol%, preferably 95.0 mol% to 99.95 mol%, more preferably 99.0 mol% to 99.93 mol%. . The saponification degree can be determined according to JIS K 6726-1994. By using a PVA-based resin having such a saponification degree, a polarizing film having excellent durability can be obtained. If the degree of saponification is too high, there is a risk of gelation.

  The average degree of polymerization of the PVA-based resin can be appropriately selected according to the purpose. The average degree of polymerization is usually 1000 to 10000, preferably 1200 to 4500, more preferably 1500 to 4300. The average degree of polymerization can be determined according to JIS K 6726-1994.

  The thickness of the PVA resin layer in the stretched laminate is typically such that the resulting polarizing film has a thickness of 10 μm or less. Specifically, the thickness of the PVA resin layer in the stretched laminate is preferably 15 μm or less, more preferably 3 μm to 15 μm, and still more preferably 5 μm to 10 μm. According to the present invention, a remarkable effect can be exhibited in such a thin PVA resin layer (finally a polarizing film).

A-4. Functional layer The functional layer preferably has heat resistance. By having heat resistance, for example, even when a temperature equal to or higher than the glass transition temperature of the polyester resin substrate is applied to the laminate, excellent blocking resistance can be realized.

The functional layer is, for example, an antistatic layer containing a conductive material and a binder resin. According to such a configuration, excellent blocking resistance can be realized, and the production efficiency can be improved. Moreover, it can be excellent in antistatic property. Any appropriate configuration can be adopted as the antistatic layer. A typical example of the conductive material is a polythiophene polymer (for example, polyethylene dioxythiophene). As the binder resin, for example, a resin that has both adhesiveness and flexibility with the resin base material and can be dissolved or dispersed in an aqueous solvent can be used. Specific examples include polyurethane resins. The thickness of the antistatic layer is preferably 0.1 μm to 10 μm. The surface resistance value of the antistatic layer is preferably less than 10 × 10 ¹³ Ω / □. The arithmetic average roughness Ra of the surface of the antistatic layer is preferably 10 nm to 100 nm.

B. Method for Producing Stretched Laminate The stretched laminate described in Item A can be produced by any suitable production method. In one embodiment, the stretched laminate includes a laminate production step in which a PVA resin layer is formed on a polyester resin substrate to produce a long laminate, and the laminate is conveyed in the longitudinal direction. However, it can be manufactured by a manufacturing method including a stretching step of stretching in the air to produce a stretched laminate.

B-1. Laminate production step In the laminate production step, a long laminate is produced by forming a PVA resin layer on a polyester resin substrate. Any appropriate method can be adopted as a method of forming the PVA-based resin layer. Preferably, a PVA resin layer is formed by applying a coating solution containing a PVA resin on a long polyester resin substrate and drying it.

  The width of the laminate produced in the laminate production step is, for example, 2000 mm to 3200 mm, preferably 2300 mm to 2800 mm, more preferably 2500 mm to 2700 mm. With such a width, a wide stretched laminate can be suitably obtained.

  The thickness of the polyester resin substrate before stretching is preferably 20 μm to 300 μm, more preferably 50 μm to 200 μm. If it is less than 20 μm, it may be difficult to form a PVA-based resin layer. If it exceeds 300 μm, an excessive load may be required for stretching.

  The resin base material may be stretched in advance (before forming the PVA resin layer). In one embodiment, it is extended in the transverse direction of a long resin substrate. The lateral direction is preferably a direction orthogonal to the extending direction of the laminate described later. In the present specification, the term “orthogonal” includes the case of being substantially orthogonal. Here, “substantially orthogonal” includes the case of 90 ° ± 5.0 °, preferably 90 ° ± 3.0 °, more preferably 90 ° ± 1.0 °.

  The stretching temperature of the resin substrate is preferably Tg-10 ° C to Tg + 50 ° C with respect to the glass transition temperature (Tg). The draw ratio of the resin substrate is preferably 1.5 times to 3.0 times.

  Arbitrary appropriate methods may be employ | adopted as the extending | stretching method of a resin base material. Specifically, it may be fixed end stretching or free end stretching. The stretching method may be dry or wet. The stretching of the resin base material may be performed in one stage or in multiple stages. When performing in multiple stages, the above-mentioned draw ratio is the product of the draw ratios of the respective stages.

  Before forming the PVA-based resin layer, the resin substrate may be subjected to surface treatment (for example, corona treatment), or an easy-adhesion layer may be formed on the resin substrate. By performing such a treatment, the adhesion between the resin substrate and the PVA resin layer and / or the functional layer can be improved.

  The coating solution is typically a solution obtained by dissolving the PVA resin in a solvent. Examples of the solvent include water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, various glycols, polyhydric alcohols such as trimethylolpropane, and amines such as ethylenediamine and diethylenetriamine. These may be used alone or in combination of two or more. Among these, water is preferable. The concentration of the PVA resin in the solution is preferably 3 to 20 parts by weight with respect to 100 parts by weight of the solvent. With such a resin concentration, a uniform coating film in close contact with the resin substrate can be formed.

  You may mix | blend an additive with a coating liquid. Examples of the additive include a plasticizer and a surfactant. Examples of the plasticizer include polyhydric alcohols such as ethylene glycol and glycerin. Examples of the surfactant include nonionic surfactants. These can be used for the purpose of further improving the uniformity, dyeability and stretchability of the resulting PVA-based resin layer.

  Any appropriate method can be adopted as a coating method of the coating solution. Examples thereof include a roll coating method, a spin coating method, a wire bar coating method, a dip coating method, a die coating method, a curtain coating method, a spray coating method, a knife coating method (comma coating method and the like).

  The drying temperature of the coating solution is preferably 50 ° C. or higher.

  The thickness of the PVA resin layer is preferably 3 μm to 25 μm, more preferably 5 μm to 10 μm.

  When providing a functional layer, the functional layer typically applies a functional layer-forming composition (for example, an antistatic layer-forming composition containing a conductive material and a binder resin) to the resin base material, It is provided by drying.

  Arbitrary appropriate methods may be employ | adopted as a coating method of the composition for functional layer formation. For example, a method similar to the coating method of the coating solution is employed. The drying temperature is preferably 50 ° C. or higher, more preferably 60 ° C. or higher. On the other hand, the drying temperature is preferably the glass transition temperature (Tg) of the resin base material + 30 ° C. or less, more preferably Tg or less.

B-2. Stretching step In the stretching step, a stretched laminate is produced by stretching in the air while transporting the laminate in the longitudinal direction. The stretching step may include a stretching step (1) for stretching the laminated body at a free end and / or a stretching step (2) for stretching the laminated body at a fixed end. The stretching step may include only one of the stretching step (1) and the stretching step (2). Preferably, the stretching step includes a stretching step (1) and a stretching step (2). In this case, the stretching step (1) may be performed first, and the stretching step (2) may be performed first. In one embodiment, an extending process (1) and an extending process (2) are performed in this order. Hereinafter, the stretching step (1) and the stretching step (2) in this embodiment will be described, and then characteristic portions of the entire stretching step will be described.

B-2-1. Stretching process (1)
The stretching in the stretching step (1) is so-called free end stretching. When the laminate is stretched in a certain direction, the laminate may shrink in a direction substantially perpendicular to the stretching direction. A method of stretching without suppressing the shrinkage is called free end stretching. For example, the free end by the width W of the laminate immediately before stretching and the stretching distance L ₁ is to stretch the laminate by the peripheral speed difference between rolls so as to satisfy the relationship of L ₁ /W≧0.3 It can be drawn.

  Stretching in the stretching step (1) is, for example, by disposing two rolls apart and stretching the laminate due to the peripheral speed difference between the rolls while transporting the laminate in the longitudinal direction by rotation of the roll. Can be done. Specifically, it can be carried out by applying tension to the laminate by the peripheral speed difference between the rolls and uniaxially stretching in the longitudinal direction. FIG. 2 is a schematic view showing an example of the stretching step (1), (a) is a view seen from the front, and (b) is a view seen from above. In the illustrated example, roll pairs 1 and 1 and roll pairs 2 and 2 are provided at a predetermined interval in the conveyance direction (MD) of the laminated body, and the laminated body 10 'is sandwiched between the respective roll pairs. ing. The roll 1 and the roll 2 rotate at different peripheral speeds, and the downstream roll 2 is set to have a higher peripheral speed than the upstream roll 1.

  Arbitrary appropriate means can be employ | adopted as a heating means to extending | stretching temperature. In the illustrated example, an oven 9 is provided between the roll 1 and the roll 2. The stretching temperature is, for example, 100 ° C. or less, preferably 95 ° C. or less. On the other hand, the stretching temperature is preferably 70 ° C. or higher. In addition, the extending | stretching temperature (temperature of a laminated body) in an extending process (1) can be confirmed using the sticker for temperature measurement, or a thermocouple, for example.

Roll 1 and roll 2, the stretching distance L _1, the width W of the laminate immediately before the stretching, is provided so as to satisfy the relationship of L ₁ /W≧0.3, preferably, 0 4 ≦ L ₁ /W≦2.0 is satisfied. Satisfying such a relationship allows free end stretching. In the present specification, the “distance between stretching” refers to a distance to which tension is applied due to a difference in peripheral speed between rolls. It is also the distance heated to the predetermined stretching temperature. For example, in the illustrated example, the length of the conveying direction of the oven 9 corresponds to the stretching distance L _1.

  The draw ratio of the drawing step (1) is preferably 1.1 times to 2.5 times, and more preferably 1.3 times to 2.0 times.

  As described above, by performing free end stretching at a predetermined temperature, the orientation of the PVA resin can be improved while suppressing shrinkage. By improving the orientation of the PVA-based resin, the orientation of the PVA-based resin can be improved even after stretching in boric acid water in the method for producing a polarizing film described later. Specifically, by previously improving the orientation of the PVA resin by this step, the PVA resin easily crosslinks with boric acid during boric acid water stretching, and boric acid becomes a node. It is presumed that the orientation of the PVA-based resin is increased even after stretching in boric acid water. As a result, a polarizing film having excellent optical characteristics can be produced.

B-2-2. Stretching process (2)
The stretching in the stretching step (2) is so-called fixed end stretching. When the laminate is stretched in a certain direction, the laminate can shrink in a direction substantially perpendicular to the stretching direction. A method of stretching while suppressing the shrinkage is called fixed-end stretching. For example, the stretching distance L ₂ to the width W 'of the laminate immediately before stretching, but by stretching the laminate by the peripheral speed difference between rolls so as to satisfy the relationship of L ₂ /W'≦0.12 It can be fixed end stretching.

  The stretching in the stretching step (2) is performed by, for example, arranging a plurality of rolls in series along the transport direction of the laminate, and rotating the plurality of rolls while transporting the laminate in the longitudinal direction, while the peripheral speed between the rolls. This can be done by stretching the laminate by the difference. FIG. 3 is a schematic view showing an example of the stretching step (2). In the illustrated example, a first roll 3, a second roll 4, and a third roll 5, each of which is temperature-controllable, are provided at predetermined intervals along the transport direction. The surface of these rolls is subjected to surface treatment (for example, plating treatment) for the purpose of preventing the laminate from sticking, for example. In the illustrated example, the laminated body 10 ′ has one surface (for example, the PVA-based resin layer 12 side) in contact with the first roll 3 and the third roll 5, and the other surface (for example, a resin base material). 11 side) is conveyed in contact with the second roll 4. The first roll 3 and the second roll 4 on the upstream side are each heated to a predetermined temperature to be a heat roll, and the stacked body 10 ′ is heated from the upper side and the lower side. In the illustrated embodiment, the laminate is stretched by the heated first roll 3 and second roll 4. Specifically, the first roll 3 and the second roll 4 rotate at different peripheral speeds, and the second roll 4 on the downstream side has a higher peripheral speed than the first roll 3 on the upstream side. Is set.

The stretching in the stretching step (2) is preferably fixed-end uniaxial stretching. Uniaxial stretching at the fixed end can contribute to the improvement of the width remaining rate. Further, for example, it is possible to prevent a problem such that the end in the width direction becomes thicker due to contraction than the central portion in the width direction, and to make the thickness uniform in the width direction. As a result, the orientation of the PVA resin layer can be improved. Above the illustrated example, for example, the first roll 3 and second roll 4, and the extending distance L _2, and 'width W' of the laminated body 10 immediately before the stretching but, L 2 _{/ W} '≦ 0 .12, and preferably satisfies the relationship L ₂ /W′≦0.06. By satisfying such a relationship, fixed end uniaxial stretching can be achieved. The inter-stretching distance L ₂ refers to the distance from the first roll 3 to the second roll 4.

  The temperature of the hot roll is preferably 110 ° C. or higher, more preferably 120 ° C. or higher. On the other hand, the temperature of the hot roll is preferably 160 ° C. or lower. By heating the laminate at such a temperature, the crystallinity of the PVA resin can be improved. Moreover, the crystallinity of PVA-type resin can further be improved by combining with free end extending | stretching. By improving the crystallinity, it is possible to prevent the PVA-based resin layer from being dissolved in water and reducing the orientation in the below-described underwater stretching. As a result, a polarizing film having excellent optical characteristics can be produced. In addition, in the said extending | stretching, even when it leaves | separates from a heat roll, a laminated body can be hold | maintained substantially at the said temperature.

  The temperature of each roll may be the same or different. In one embodiment, all roll temperatures are the same. In another embodiment, the roll temperature may be set to be low on the downstream side. In the example of illustration, the 3rd roll 5 may be set to arbitrary appropriate temperature, for example, is set to below the glass transition temperature (Tg) of a laminated body, and cools a laminated body. By cooling in this way, it can suppress that a wrinkle generate | occur | produces in a laminated body (for example, it will be in the state which waved in the shape of a tin). The temperature of the cooling roll is, for example, 30 ° C to 50 ° C.

  In the illustrated example, three rolls are used, but various conditions such as the total number of rolls to be used, the number of heat rolls and / or cooling rolls, and the arrangement order of the heat rolls and / or cooling rolls can be changed as appropriate. Needless to say.

  The draw ratio of the drawing step (2) is preferably 1.1 times to 2.0 times, more preferably 1.2 times to 1.8 times.

B-2-3. Overall stretching process The total stretching ratio in the stretching process is preferably 1.8 times to 3.2 times, more preferably 1.9 times to 3.0 times, and even more preferably, with respect to the original length of the laminate. 2.0 times to 2.5 times. When the stretching step includes the stretching step (1) and the stretching step (2), the total stretching ratio is a product of the stretching ratio in the stretching step (1) and the stretching ratio in the stretching step (2). When the total draw ratio is within this range, a polarizing film having excellent optical property uniformity can be suitably obtained.

（式中、Ｗは延伸工程前の積層体の幅、Ｗ_ｉは理想収縮による延伸積層体の幅、Ｘは総延伸倍率を表す。） The width (W _i ) of the stretched laminate by ideal shrinkage calculated from the total stretch ratio and the width (W _r ) of the actually obtained stretched laminate are preferably 1 ≦ W _r / W _i ≦ 1. 1 is satisfied, more preferably 1 ≦ W _r / W _i ≦ 1.08. When such a relationship is satisfied, the occurrence of bowing during air stretching can be suitably suppressed. As a result, it is possible to obtain a PVA-based resin layer (as a result, a polarizing film that is more excellent in optical property uniformity) that is more excellent in uniformity of alignment. In addition, the width | _variety ( _Wi ) of the extending | stretching laminated body by ideal shrinkage | contraction is calculated by introduce | transducing each value into the following formula | equation.

(Wherein, W is the width of the stack before the stretching process, W _i is the width of the stretched laminate according to the ideal shrinkage, X represents the total draw ratio.)

  The ratio [(1) / (2)] of the draw ratio in the drawing step (1) and the drawing step (2) is preferably 1.2 or less, more preferably 0.85 to 1.15, and still more preferably 0.8. 9 to 1.1. When the stretching ratio is within this range, a polarizing film having excellent optical property uniformity can be suitably obtained.

C. Method of Use The stretched laminate of the present invention is typically used for the production of a polarizing film. Specifically, the stretched laminate of the present invention is appropriately subjected to a treatment for using the PVA resin layer as a polarizing film. Examples of the treatment for forming the polarizing film include stretching treatment, dyeing treatment, insolubilization treatment, crosslinking treatment, washing treatment, and drying treatment. In addition, the frequency | count, order, etc. of these processes are not specifically limited.

C-1. Underwater stretching In a preferred embodiment, the stretched laminate is stretched in water (stretched in boric acid in water). Specifically, it is stretched in water in a direction parallel to the stretching direction of the laminate. According to the stretching in water, the PVA resin layer can be stretched at a temperature lower than the glass transition temperature (typically about 80 ° C.) of the resin base material and the PVA resin layer while suppressing the crystallization. It can be stretched at a high magnification. As a result, a polarizing film having excellent optical characteristics (for example, the degree of polarization) can be produced. In this specification, the “parallel direction” includes the case of 0 ° ± 5.0 °, preferably 0 ° ± 3.0 °, more preferably 0 ° ± 1.0 °. .

  Arbitrary appropriate methods can be employ | adopted for the extending | stretching method of an extending | stretching laminated body. Specifically, it may be fixed end stretching or free end stretching. The stretching direction of the stretched laminate is substantially the stretching direction (longitudinal direction) of the above-described air stretching. Stretching of the stretched laminate may be performed in one stage or in multiple stages.

  The stretching in water is preferably performed by immersing the stretched laminate in an aqueous boric acid solution (stretching in boric acid in water). By using an aqueous boric acid solution as the stretching bath, the PVA resin layer can be provided with rigidity that can withstand the tension applied during stretching and water resistance that does not dissolve in water. Specifically, boric acid can form a tetrahydroxyborate anion in an aqueous solution and crosslink with a PVA resin by hydrogen bonding. As a result, rigidity and water resistance can be imparted to the PVA-based resin layer, the film can be stretched satisfactorily, and a polarizing film having excellent optical characteristics (for example, polarization degree) can be produced.

  The boric acid aqueous solution is preferably obtained by dissolving boric acid and / or borate in water as a solvent. The boric acid concentration is preferably 1 to 10 parts by weight with respect to 100 parts by weight of water. By setting the boric acid concentration to 1 part by weight or more, dissolution of the PVA resin layer can be effectively suppressed, and a polarizing film having higher characteristics can be produced. In addition to boric acid or borate, an aqueous solution obtained by dissolving a boron compound such as borax, glyoxal, glutaraldehyde, or the like in a solvent can also be used.

  When a dichroic substance (typically iodine) is previously adsorbed to the PVA-based resin layer by dyeing treatment described later, preferably, an iodide is blended in the stretching bath (boric acid aqueous solution). By blending iodide, elution of iodine adsorbed on the PVA resin layer can be suppressed. Examples of the iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Etc. Among these, potassium iodide is preferable. The concentration of iodide is preferably 0.05 to 15 parts by weight, more preferably 0.5 to 8 parts by weight with respect to 100 parts by weight of water.

  The stretching temperature of the stretching in water (liquid temperature of the stretching bath) is preferably 40 ° C to 85 ° C, more preferably 50 ° C to 85 ° C. If it is such temperature, it can extend | stretch at high magnification, suppressing melt | dissolution of a PVA-type resin layer. Specifically, as described above, the glass transition temperature (Tg) of the polyester resin base material is preferably 60 ° C. or higher in relation to the formation of the PVA resin layer. In this case, when the stretching temperature is lower than 40 ° C., there is a possibility that the stretching cannot be satisfactorily performed even in consideration of plasticization of the polyester-based resin substrate with water. On the other hand, the higher the temperature of the stretching bath, the higher the solubility of the PVA-based resin layer, and there is a possibility that excellent optical properties cannot be obtained. The immersion time of the stretched laminate in the stretching bath is preferably 15 seconds to 5 minutes.

  By combining the polyester-based resin base material and stretching in water (boric acid stretching in water), it is possible to stretch at a high magnification and to produce a polarizing film having excellent optical properties (for example, polarization degree). . Specifically, the maximum draw ratio is preferably 5.0 times or more, more preferably 5.5 times or more, even more preferably with respect to the original length of the laminate (including the draw ratio of the stretched laminate). Is 6.0 times or more. In the present specification, the “maximum stretch ratio” refers to a stretch ratio immediately before the stretched laminate breaks, and separately confirms a stretch ratio at which the stretched laminate breaks, and refers to a value 0.2 lower than that value. . In addition, the maximum draw ratio of the laminated body using the said polyester-type resin base material can become higher in the direction which passed through underwater drawing rather than extending | stretching only by air drawing.

C-2. Others The dyeing process is typically a process of dyeing a PVA resin layer with a dichroic substance. Preferably, it is performed by adsorbing a dichroic substance to the PVA resin layer. As the adsorption method, for example, a method of immersing a PVA resin layer (stretched laminate) in a dye solution containing a dichroic substance, a method of applying the dye solution to a PVA resin layer, and a method of applying the dye solution to PVA And a method of spraying on the resin layer. Preferably, the stretched laminate is immersed in a dyeing solution containing a dichroic substance. It is because a dichroic substance can adsorb | suck favorably.

  As said dichroic substance, an iodine and a dichroic dye are mentioned, for example. Preferably, it is iodine. When iodine is used as the dichroic substance, the staining solution is an iodine aqueous solution. The compounding amount of iodine is preferably 0.1 part by weight to 0.5 part by weight with respect to 100 parts by weight of water. In order to increase the solubility of iodine in water, it is preferable to add an iodide to the aqueous iodine solution. Specific examples of the iodide are as described above. The amount of iodide is preferably 0.02 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, and even more preferably 0.7 to 3 parts by weight with respect to 100 parts by weight of water. .5 parts by weight. The liquid temperature during dyeing of the dyeing liquid is preferably 20 ° C. to 50 ° C. in order to suppress dissolution of the PVA resin. When the PVA resin layer is immersed in the staining solution, the immersion time is preferably 5 seconds to 5 minutes in order to ensure the transmittance of the PVA resin layer. The staining conditions (concentration, liquid temperature, immersion time) can be set so that the polarization degree or single transmittance of the finally obtained polarizing film is within a predetermined range. In one embodiment, immersion time is set so that the polarization degree of the polarizing film obtained may be 99.98% or more. In another embodiment, the immersion time is set so that the single transmittance of the obtained polarizing film is 40% to 44%.

  Preferably, the dyeing treatment is performed before the above-described stretching in water.

  The insolubilization treatment is typically performed by immersing the PVA resin layer in an aqueous boric acid solution. By performing the insolubilization treatment, water resistance can be imparted to the PVA resin layer. The concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight with respect to 100 parts by weight of water. The liquid temperature of the insolubilizing bath (boric acid aqueous solution) is preferably 20 ° C to 50 ° C. Preferably, the insolubilization treatment is performed before the above-described underwater stretching or the above-described dyeing treatment.

  The crosslinking treatment is typically performed by immersing the PVA resin layer in an aqueous boric acid solution. By performing the crosslinking treatment, water resistance can be imparted to the PVA resin layer. The concentration of the boric acid aqueous solution is preferably 1 to 4 parts by weight with respect to 100 parts by weight of water. Moreover, when performing a crosslinking process after the said dyeing | staining process, it is preferable to mix | blend an iodide further. By blending iodide, elution of iodine adsorbed on the PVA resin layer can be suppressed. The blending amount of iodide is preferably 1 part by weight to 5 parts by weight with respect to 100 parts by weight of water. Specific examples of the iodide are as described above. The liquid temperature of the crosslinking bath (boric acid aqueous solution) is preferably 20 ° C to 50 ° C. Preferably, the crosslinking treatment is performed before the underwater stretching. In a preferred embodiment, the dyeing process, the crosslinking process and the underwater stretching are performed in this order.

  The cleaning treatment is typically performed by immersing the PVA resin layer in an aqueous potassium iodide solution. The drying temperature in the drying treatment is preferably 30 ° C to 100 ° C.

  FIG. 4 is a schematic view showing an example of a method for producing a polarizing film. The stretched laminate 10 is unwound from the unwinding unit 101 and immersed in a boric acid aqueous solution bath 110 by rolls 111 and 112 (insolubilization treatment). Immerse in an aqueous solution bath 120 (dyeing treatment). Next, the rolls 131 and 132 are immersed in a bath 130 of an aqueous solution of boric acid and potassium iodide (crosslinking treatment). Thereafter, the stretched laminate 10 is stretched by applying tension in the longitudinal direction (longitudinal direction) with rolls 141 and 142 having different speed ratios while being immersed in a bath 140 of a boric acid aqueous solution (stretching in water). The stretched laminate 10 stretched in water is immersed in a bath 150 of a potassium iodide aqueous solution by rolls 151 and 152 (cleaning treatment) and subjected to a drying treatment (not shown). Thereafter, the stretched laminate 10 is wound up by the winding unit 160.

D. Polarizing film As described above, a polarizing film is formed on the resin substrate by subjecting the stretched laminate of the present invention to the above-described treatments. This polarizing film is substantially a PVA resin film in which a dichroic substance is adsorbed and oriented. The thickness of the polarizing film is preferably 10 μm or less, more preferably 7 μm or less, and still more preferably 5 μm or less. On the other hand, the thickness of the polarizing film is preferably 0.5 μm or more, more preferably 1.5 μm or more. The polarizing film preferably exhibits absorption dichroism at any wavelength of 380 nm to 780 nm. The single transmittance of the polarizing film is preferably 40.0% or more, more preferably 41.0% or more, and further preferably 42.0% or more. The polarization degree of the polarizing film is preferably 99.980% or more, and more preferably 99.982% or more.

  The width of the polarizing film is preferably 1000 mm or more, more preferably 1100 mm to 1500 mm. Even if the polarizing film produced by using the stretched laminate of the present invention is wide as described above, it can be excellent in uniformity of optical properties. As a result, it is possible to prevent a difference in optical characteristics from occurring in the single-wafer type polarizing film due to the difference in the punching location.

  Any appropriate method can be adopted as a method of using the polarizing film. Specifically, it may be used in a state integrated with the resin base material, or may be transferred from the resin base material to another member for use.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples. In addition, the measuring method of each characteristic is as follows.
(1) Thickness About the laminated body, the thickness of the laminated body of the width direction was measured using the contact type desktop type | mold offline thickness measuring apparatus (the Yamabun Electric company make, model TOF-5R). About the PVA-type resin layer of the extending | stretching laminated body, it measured using the interference film thickness meter (The Ocean optics company make, continuous thickness measuring device).
(2) Glass transition temperature (Tg)
It measured according to JIS K7121.
(3) Birefringence (Δn) of PVA resin layer
The front phase difference of the PVA resin layer at a wavelength of 590 nm was measured using an automatic birefringence meter (product name “KOBRA-WPR” manufactured by Oji Scientific Instruments). Birefringence (Δn) was determined by dividing the obtained front phase difference (R ₀ ) by the thickness (d (nm)) of the PVA-based resin layer (Δn = R ₀ / d).
(4) Variation in orientation angle of PVA-based resin layer The orientation angle of the PVA-based resin layer in the width direction was measured using AxoScan manufactured by Axometrics. The difference between the maximum value and the minimum value of the measured values was defined as the variation in the orientation angle.
(5) Polarization degree Using a UV-visible spectrophotometer (manufactured by JASCO Corporation, product name “V7100”), the single transmittance (Ts), parallel transmittance (Tp) and orthogonal transmittance (Tc) of the thin polarizing film Was measured, and the degree of polarization (P) was determined by the following equation.
Polarization degree (P) (%) = {(Tp−Tc) / (Tp + Tc)} 1/2 × 100
Note that Ts, Tp, and Tc are Y values measured with a two-degree field of view (C light source) of JIS Z 8701 and corrected for visibility.
(6) Axial displacement amount of polarizing film Using AxoScan manufactured by Axometrics, the orientation angle of the polarizing film in the width direction was measured to determine the axial displacement amount of the polarizing film.
(7) Width remaining ratio The ratio of the width of the stretched laminate to the width of the laminate before the stretching step was calculated as the width remaining rate (%).

[Example 1]
(Laminate production process)
Water-based urethane resin (Daiichi Kogyo Seiyaku Co., Ltd., trade name: Superflex 210R, solid content: 35%), oxazoline-based cross-linking agent (manufactured by Nippon Shokubai Co., Ltd., trade name: Epocross WS700, solid content: 25% ), Conductive material (manufactured by Agfa, trade name: Olgacon LBS, solid content: 1.2%), ammonia water having a concentration of 1% and water in a weight ratio of 9.03: 1.00: 18.1: 0.060. : 39.5 mixed solution was prepared.
The obtained mixed liquid was dried on one surface of a 200 μm thick long amorphous polyethylene terephthalate (A-PET) film (Tg: 70 ° C., Mitsubishi Plastics, trade name: SH046). It applied so that thickness might be set to 1 micrometer.
Subsequently, the A-PET film was stretched twice in the transverse direction at 115 ° C. while being conveyed in the longitudinal direction.
Next, an aqueous solution of polyvinyl alcohol (degree of polymerization: 4200, degree of saponification: 99.2 mol%) is applied to the other surface of the A-PET film, dried at 60 ° C., and a PVA system having a thickness of 10 μm. A resin layer was formed.
In this way, a laminate having a width of 2500 mm was obtained.

(Stretching process)
As shown in FIG. 2, the laminated body obtained by the roll pair provided in each of the inlet and outlet of temperature-controllable oven (length L ₁ : 1500 mm, L _{1 /} W: 0.6 in the conveying direction) Was stretched 1.35 times in the longitudinal direction with a peripheral speed difference between these rolls (stretching step (1)). At that time, the temperature and the air volume of the oven were appropriately adjusted, and the maximum temperature reached of the laminate during stretching was set to 88 ° C. In addition, the temperature (maximum ultimate temperature) of the laminated body at the time of extending | stretching was confirmed by sticking the heat label (the product number: 6R-65 or 6R-99 by Micron Corporation) on the surface of the laminated body.
Subsequently, as shown in FIG. 3, the surface was subjected to hard chrome plating, and the laminate was passed through three iron rolls capable of temperature control (stretching step (2)). Here, the PVA-based resin layer surface of the laminate was brought into contact with the first roll and the third roll, and the other surface (base material side) was brought into contact with the second roll. The surface temperature of the 1st roll and the 2nd roll was 120 degreeC, and the surface temperature of the 3rd roll was 50 degreeC. The first roll and the second roll were stretched 1.48 times with a peripheral speed difference. In addition, the width W ′ of the laminate immediately before passing through the first roll is 2150 mm, and the distance L ₂ from the first roll to contact with the second roll is 100 mm, and L ₂ / W ′ was 0.047. Moreover, the width | variety of the extending | stretching laminated body after passing a 3rd roll was 1940 mm.

The obtained stretched laminate was immersed in a 3 wt% boric acid aqueous solution (insolubilized bath) having a liquid temperature of 30 ° C for 30 seconds (insolubilization treatment).
Subsequently, the single transmittance (Ts) of the polarizing film finally obtained in a dyeing bath (iodine aqueous solution obtained by mixing iodine and potassium iodide in water at a weight ratio of 1: 7) at a liquid temperature of 30 ° C. ) Was soaked at an arbitrary concentration and an arbitrary time so as to be 40 to 44% (dyeing treatment).
Then, it was immersed for 30 seconds in an aqueous solution (crosslinking bath) containing 3% by weight of boric acid and 3% by weight of potassium iodide at a liquid temperature of 30 ° C. (crosslinking treatment).
Thereafter, until the laminate is broken in the longitudinal direction (longitudinal direction) between a plurality of sets of rolls having different peripheral speeds in an aqueous solution containing boric acid 4 wt% and potassium iodide 5 wt% at a liquid temperature of 70 ° C. Uniaxial stretching was performed (stretching in boric acid in water).
Then, after dipping in a 4% by weight aqueous solution of potassium iodide (cleaning bath) having a liquid temperature of 30 ° C., it was dried with hot air at 60 ° C. (cleaning / drying treatment).
In this way, a polarizing film having a thickness of 4.5 μm was obtained.

[Example 2]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.40 times and the stretch ratio in the stretching step (2) was 1.43 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.047, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1913 mm.

[Example 3]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.45 times and the stretch ratio in the stretching step (2) was 1.38 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.048, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1933 mm.

[Example 4]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.50 times and the stretch ratio in the stretching step (2) was 1.33 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.049, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1910 mm.

[Example 5]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.55 times and the stretch ratio in the stretching step (2) was 1.29 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.050, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1923 mm.

[Example 6]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.70 times and the stretch ratio in the stretching step (2) was 1.41 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.052, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1850 mm.

[Example 7]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.50 times and the stretch ratio in the stretching step (2) was 1.60 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.049, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1853 mm.

[Example 8]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.60 times and the stretch ratio in the stretching step (2) was 1.50 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.051, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1845 mm.

[Example 9]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.62 times and the stretch ratio in the stretching step (2) was 1.36 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.051, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1868 mm.

[Comparative Example 1]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.60 times and the stretch ratio in the stretching step (2) was 1.25 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.051, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1903 mm.

[Comparative Example 2]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.65 times and the stretch ratio in the stretching step (2) was 1.21 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.051, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1920 mm.

[Comparative Example 3]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.70 times and the stretch ratio in the stretching step (2) was 1.18 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.052, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1898 mm.

[Comparative Example 4]
A stretched laminate and a polarizing film were prepared in the same manner as in Example 1 except that the stretch ratio in the stretching step (1) was 1.80 times and the stretch ratio in the stretching step (2) was 1.33 times. Obtained. Note that L ₁ / W and L ₂ / W ′ in the stretching step were 0.6 and 0.054, respectively. Moreover, the width | variety of the obtained extending | stretching laminated body was 1855 mm.

Table 1 shows the stretching conditions in each Example and Comparative Example and the measurement results of the obtained stretched laminate.

[Reference Example 1]
Except that various stretching ratios were applied in the stretching step (1) and the stretching step (2), variations in orientation angles in the PVA resin layers of the various stretched laminates obtained in the same manner as in Example 1 and the stretching FIG. 5 shows the relationship with the amount of axial misalignment in the polarizing film produced from the laminate. As shown in FIG. 5, it can be seen that a polarizing film in which axial misalignment is suppressed can be obtained by using a stretched laminate having a PVA-based resin layer with small alignment angle variation and excellent axial accuracy. Specifically, by setting the variation in the width direction of the orientation angle of the PVA-based resin layer in the stretched laminate to 4 ° or less, a polarizing film having an axial misalignment of 0.5 ° or less can be obtained.

[Reference Example 2]
A polarizing film of a predetermined size was punched out from various places of the long polarizing film obtained in the example, and the amount of axial deviation was measured. The degree of polarization when a polarizing film having an axial deviation of 0 ° to 0.5 ° is selected, the polarizing film is used as a lower polarizing film, and a polarizing film having an axial deviation of 0 ° is used as an upper polarizing film is obtained. It was measured. When measuring the degree of polarization, an adhesive (3% aqueous solution of GOHSEIMER Z200 manufactured by Nihon Gosei Co., Ltd.) was applied to the surface of the obtained polarizing film, and a triacetyl cellulose (TAC) film having a thickness of 80 μm (manufactured by Fuji Film Co., Ltd.). , Trade name “TD80UL”, thickness 80 μm) were bonded together and heated at 60 ° C. for 5 minutes, and then the substrate (A-PET film) was peeled off. Thus, the polarizing film was transferred to a TAC film and used for measurement of the degree of polarization. FIG. 6 shows the relationship between the amount of axial displacement of the polarizing film and the degree of polarization.

  As shown in FIG. 6, it can be seen that a high degree of polarization of 99.98% or more can be secured if the amount of axial misalignment of the polarizing film is 0.5 ° or less.

  As shown in Table 1, the stretched laminate of the present invention has a variation in orientation angle in the width direction of the PVA resin layer of 4 ° or less. Considering the result of the reference example together, the polarizing film obtained using the stretched laminate of the present invention has excellent axial accuracy and can achieve a high degree of polarization (for example, 99.98% or more).

  The stretched laminate of the present invention is suitably used for producing a polarizing film. The obtained polarizing film has high optical characteristics and can be suitably used for, for example, a liquid crystal panel or an organic EL panel.

DESCRIPTION OF SYMBOLS 1 Roll 2 Roll 3 1st roll 4 2nd roll 5 3rd roll 9 Oven 10 Stretched laminated body 10 'Laminated body 11 Polyester-type resin base material 12 PVA-type resin layer

Claims (8)

A long stretched laminate comprising a polyester resin substrate and a polyvinyl alcohol resin layer formed on the substrate,
The stretched laminate has a width of 1500 mm to 2700 mm,
The variation in the orientation angle in the width direction of the polyvinyl alcohol-based resin layer is 4.0 ° or less.
Stretched laminate. The stretched laminate according to claim 1, wherein birefringence (Δn) in the front direction of the polyvinyl alcohol-based resin layer satisfies a relationship of 5 × 10 ⁻³ <Δn <30 × 10 ⁻³ .   The stretched laminate according to claim 1 or 2, wherein the polyvinyl alcohol-based resin layer has a thickness of 15 µm or less. A method for producing the stretched laminate according to any one of claims 1 to 3,
A laminate production process for producing a long laminate by forming a polyvinyl alcohol resin layer on a polyester resin substrate,
Stretching process for producing a stretched laminate by stretching in the air while transporting the laminate in the longitudinal direction;
The manufacturing method of the extending | stretching laminated body containing this.   The manufacturing method of the extending | stretching laminated body of Claim 4 in which the said extending | stretching process includes the extending process (1) which extends the said laminated body at a free end, and the extending process (2) which carries out the fixed end extending | stretching of the said laminated body. .   The manufacturing method of the extending | stretching laminated body of Claim 5 whose ratio [(1) / (2)] of the draw ratio in an extending process (1) and an extending process (2) is 1.2 or less. The total draw ratio in the drawing step is 1.8 to 3.2 times,
When the width of the stretched laminate by ideal shrinkage calculated from the total draw ratio is W _i and the width of the actually obtained stretched laminate is W _r , 1 ≦ W _r / W _i ≦ 1.1 The manufacturing method of the extending | stretching laminated body in any one of Claim 4 to 6 satisfy | filling these relationships.   The polarizing film produced using the extending | stretching laminated body in any one of Claim 1 to 3.

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