JP2009048162A - Manufacturing method of polarizing plate - Google Patents

Abstract

The present invention provides a method capable of stably and continuously producing a polarizing plate exhibiting desired polarization characteristics.
(A) preparing a long polymer film that has not been treated or at least subjected to a first treatment; and (b) a long polarizing film that has not been treated or at least subjected to a second treatment. Preparing (c) at least a long polymer film prepared in (a) and a long polarizing film prepared in (b) are laminated to obtain a long laminate. To obtain at least one characteristic value α indicating the polarization characteristics of the long laminate obtained in (d) and (c), and (e) the characteristic value α measured in (d), Comparing with the determined design value α ₀ , (f) Based on the comparison of (e), (a) first process, (b) second process, and (c) pasting Production of a polarizing plate comprising controlling at least one condition during at least one process selected from a combination process It is the law.
[Selection] Figure 1

Description

  The present invention relates to a method for producing a polarizing plate, and more particularly to a method for continuously producing a long polarizing plate.

It is desirable that the polarization characteristics of the polarizing plate be optimized according to the mode of the liquid crystal display device in which it is used. By the way, since a polarizing plate is generally a laminate having a polarizing film and a protective film made of a polymer film on both sides thereof, the polarizing property of the polarizing plate as a laminate is that of a polymer film used as a protective film. It is greatly influenced by optical characteristics, specifically, in-plane retardation and retardation in the thickness direction. Therefore, a protective film is usually designed so as to obtain a polarizing plate having desired polarization characteristics, and a polymer film according to the design is manufactured and used for manufacturing a polarizing plate. Therefore, conventionally, the problem of continuously and stably producing a polarizing plate having a desired polarization characteristic is usually that a polymer film designed for a protective film for a polarizing plate is continuously processed so that there is no fluctuation in optical characteristics. It has been achieved by manufacturing stably and continuously laminating with a polarizing film.
An example of a method for producing a retardation film having a small retardation variation over the entire surface of the film is described in Patent Document 1.
Moreover, the method of patent documents 2-5 is also proposed as a manufacturing method of a polarizing plate.
JP 2001-272537 A Japanese Patent No. 3908470 Japanese Patent No. 3615538 Japanese Patent No. 3315256 Japanese Patent No. 3427130

  An object of the present invention is to provide a method capable of stably and continuously producing a polarizing plate exhibiting desired polarization characteristics.

  Conventionally, in the production of polarizing plates, the processing steps of the polymer film and the conditions for the bonding treatment between the polymer film and the polarizing film are controlled so that the optical properties of the polymer film used as the protective film do not vary from the design value. However, the present invention is completely different from this concept of the prior art, and the characteristic value indicating the polarization characteristic of the laminate of the polymer film and the polarizing film is measured, and the measured value is compared with the design value to protect it. The conditions for the treatment applied to the polymer film for the film, the treatment applied to the polarizing film, or the bonding treatment thereof are controlled.

That is, the means for solving the problems are as follows.
[1] The following (a) to (c):
(A) preparing a long polymer film that has not been treated or at least subjected to a first treatment;
(B) preparing a long polarizing film that has not been processed or at least subjected to the second processing;
(C) Bonding at least the long polymer film prepared in (a) and the long polarizing film prepared in (b) to obtain a long laminate;
Is a method for producing a polarizing plate continuously,
(D) obtaining at least one characteristic value α indicating the polarization characteristics of the long laminate obtained in (c);
(E) comparing the characteristic value α obtained in (d) with a predetermined design value α ₀ ;
(F) Based on the comparison in (e), at least one condition of at least one process selected from the first process in (a), the second process in (b), and the bonding process in (c) A method for producing a polarizing plate, comprising:
[2] The method according to [1], wherein the characteristic value α is the dichroic vector D and / or the polarization vector P of the laminate.
[3] In (e), the difference ΔD between the dichroic vector D of the laminate and the design value D ₀ of the dichroism vector, and / or the polarization ability vector P of the laminate and the depolarization design value DP The method of [2], wherein a difference ΔDP from ₀ is calculated.
[4] In (d), the polarized light passing through the laminate is detected using a dual rotation retarder type polarimeter, and the dichroic vector D and / or polarization ability vector of the laminate is detected from the detected value. The method of [2] or [3], wherein P is calculated.
[5] In (d), the polarization state of the light incident from the direction inclined by the polar angle θ (0 ° <θ <90 °) with respect to the surface of the laminate is detected, and the dichroism is detected from the detected value. The method according to [4], wherein the vector D and / or the polarization vector P is calculated.
[6] In (d), the direction inclined by the polar angle θ with respect to the surface of the laminate in the direction of azimuth φ (0 ° <φ <90 °) with reference to the longitudinal direction of the long laminate The method according to [5], wherein the polarization state of the light incident from is detected and the dichroic vector D and / or the polarization vector P is calculated from the detected value.
[7] The method according to any one of [1] to [6], wherein in (d), a characteristic value of at least a polarizing film and a laminate having a polymer film on each of both surfaces thereof is obtained.
[8] The first treatment is a treatment that affects the in-plane retardation of the polymer film and / or the retardation in the thickness direction. In (f), at least one condition of the first treatment is controlled. Any one of the methods [1] to [7].
[9] The method according to [8], wherein the first treatment is at least one treatment selected from a saponification treatment, a stretching treatment, and an adhesive coating treatment.
[10] In (a), at least a saponified polymer film is prepared. In (f), at least one condition selected from the saponification time, temperature, and base concentration of the treatment liquid is controlled. Any one of the methods [1] to [9].
[11] In any one of [1] to [10], in (a), at least a polymer film subjected to stretching treatment is prepared, and in (f), the stretching ratio of the stretching treatment is controlled. the method of.
[12] In (a), a polymer film subjected to at least an adhesive coating treatment is prepared, and / or in (b), a polarizing film subjected to at least an adhesive coating treatment is prepared, (f) In (a) and / or (b), at least one condition of time, temperature, pressure-sensitive adhesive concentration, coating amount, and drying time of the pressure-sensitive adhesive coating treatment is controlled [1] to [1] 7] Any one of the methods.

  According to the present invention, the polymer film used as the protective film or the treatment conditions applied to the polarizing film is controlled based on the polarization characteristics of the polarizing plate itself such as the dichroic vector and the polarization ability vector, so that the stability is stable. Thus, a polarizing plate that continuously exhibits desired polarization characteristics can be produced.

Hereinafter, the manufacturing method of the polarizing plate of this invention is demonstrated in detail with reference to drawings. In the present specification, “to” indicates a range including the numerical values described before and after the minimum and maximum values, respectively.
FIG. 1 is a schematic diagram showing an example of a method for producing a polarizing plate of the present invention.
The long polymer film 12 wound up in a roll shape is conveyed in the longitudinal direction by the rotating rolls 13 and 15 (polymer film 12a). The polymer film 12a is stretched by the difference in rotational speed between the rotating rolls 13 and 15, and is processed by the processing means 14 (polymer film 12b), and further processed by the processing means 16 (polymer film c). To the nip portion of the pressure roll 26.

  On the other hand, the long polarizing film 18 wound up in a roll shape is conveyed in the longitudinal direction (polarizing film 18 a), processed by the processing means 20 (polarizing film 18 b), and then applied to the nip portion of the pressure roll 26. Sent. Similarly, the long polymer film 22 wound up in a roll shape is conveyed in the longitudinal direction (polymer film 22a) and processed by the processing means 24 (polymer film 22b)), and then the nip of the pressure roll 26. Sent to the department.

The polymer film 12 c, the polarizing film 18 b, and the polymer film 22 b are pressed in a laminated state at the nip portion of the pair of pressure rolls 26 to be an integrated laminate 28 a, conveyed in the longitudinal direction, and processed by the processing means 30. After being processed (laminate 22b), it becomes the polarizing plate 28 and is wound up in a roll shape. Before being wound into a roll, the polarization characteristics of the laminate 28 b are detected by the detector 32 and input to the calculator 34. The calculator 34 calculates a predetermined characteristic value α indicating the polarization characteristic based on the input detection value, and compares it with a corresponding design value α ₀ input in advance. For example, the difference Δα between α and α ₀ is calculated and displayed on a monitor (not shown).

The characteristic value α used for controlling the processing conditions is preferably a value indicating the polarization characteristic of the laminate 28b, and is a dichroic vector D or a polarizability vector P. preferable. A dichroism vector D represents a polarization state in which the amount of transmitted light is maximum on the Poincare sphere, and a polarization ability (polarizance) vector P represents when non-polarized light is incident on the Poincare sphere. Represents the output polarization state. It is preferable to use a dual rotation retarder polarimeter as the detector 32 because D and P of a laminate of a polarizing film and a birefringent polymer film can be measured. A dual rotation retarder polarimeter is a polarimeter that includes a polarization generator that generates polarization and a polarization analyzer that detects polarization. Both heads are composed of a wave plate and a polarizer that rotate at high speed. It is the polarimeter which is comprised. As a commercial product, there is a Mueller matrix polarimeter manufactured by Axometrics, which can be used.
The characteristic value α may be a component obtained by renormalization ellipsometry or generalized ellipsometry, Stokes parameter (S123), extinction, transmittance, reflectance, retardation, haze, scattering rate, slow axis, It may be at least one selected from a polarization axis, moisture permeability, elastic modulus, moisture content, charging rate, conductivity, and resistance value.

Characteristic values obtained by renormalization ellipsometry include t _pp , t _ps , t _sp , t _ss, etc., and these characteristic values satisfy the following formula.

  In the isotropic medium, the non-diagonal component in the Jones matrix is 0, but in the optically anisotropic medium, it generally has a value other than 0. In renormalization ellipsometry, ψ and Δ are obtained as measured values, and the measured values are used for analysis according to the following equation.

  On the other hand, in generalized ellipsometry, the following three items including non-diagonal components are measured.

  In general, Δ is a parameter mainly related to the phase difference of the P wave S wave, and ψ is the intensity ratio of the P wave S wave. Therefore, by analyzing these values, it is possible to obtain information on the retardance and absorption of the sample. It is possible to compare the theoretical value and the measured value of the multilayer model and fit the model parameters so that the difference is minimized.

  The above methods are described by N. Tanaka, M. Kimura and T. Akahane: Jpn. J. Appl. Phys. 42 (2003) 486-491 for renormalization ellipsometry; and M. for generalized ellipsometry. Schubert, B. Rheinlander, C. Cremer, H. Schmiedel, JA Woollam, CM Herzinger and B. Johs: J. Opt. Soc. Am. A13 (1996) 1930-1940.

  Moreover, said measuring method is applicable also to the state by which the panel and the polarizing plate were bonded, and the measurement of only a panel. The panel has a multilayer structure including liquid crystal, alignment film, color filter, transparent electrode, ITO, transparent insulating film, glass and the like. By modeling them, comparing the theoretical values and measured values from the model, and fitting the model parameters so that the difference is minimized, the physical parameters (refractive index, absorption coefficient, birefringence of each layer above) Rate, film thickness, etc.). By designing using these parameters, the parameters of the optical film and the panel can be obtained. Furthermore, by performing the above measurement for each wavelength, it is possible to obtain ideal parameters for good color. Further, when the above measurement is performed with a voltage applied to the cell, ideal parameters can be obtained not only for the black state and the white state but also for the display performance of the halftone.

  Furthermore, for complex systems involving interference, the extended Jones vector is further expanded as in Y. Ohno, T. Ishinabe, T. Miyashita and T. Uchida, IDW '07 p. 47 (2007). Can be used to obtain more accurate parameters.

In FIG. 2, a dual rotation retarder type polarimeter is used as the detector 32, and the dichroic vector D of the laminate 28b (in the figure, the laminate structure is omitted and shown as a single layer), and An example of a method for measuring the polarization ability vector P is shown. The detector 32 creates polarized waves by the polarization generator 32a, enters the stacked body 28b, and detects the polarized light that has passed through the stacked body 28b by the polarization analyzer 32b.
When the polymer film 12c and / or the polymer film 22b laminated on the polarizing film 18b is a birefringent film showing retardation, the polar angle θ (0 ° <θ <) with respect to the normal direction of the surface of the laminate 28b. It is preferable that the polarized light is incident from a direction inclined by 90 °), and the polar angle θ from the normal line in the direction of the azimuth angle φ (0 ° <φ <90 °) with respect to the longitudinal direction d1 of the laminate 28b. It is preferable to detect the polarization state of the light that has entered the polarized light from the tilted direction.
θ is preferably 30 to 70 °, and φ is preferably ± 30 to ± 60 °. The detection value indicating the polarization state detected by the polarization analyzer 32b is input to the calculator 34, and the dichroism vector D and / or the polarization ability vector P are calculated. An optimal design value D ₀ and / or P ₀ of a polarizing plate designed in accordance with the use of the polarizing plate is input to the computer 34 in advance by theoretical calculation by mounting evaluation or modeling, and the calculated D and the difference [Delta] D ₀ or [Delta] P ₀ of the design value D ₀ or P ₀ is calculated as P. It may be detected continuously and ΔD ₀ or ΔP ₀ may be monitored. Further, D and P, D ₀ and P ₀ can be handled in the same manner even if they are standardized.
The above method is described in detail in Y. Ootani: O plus E 29 p.20 (2007)); and SY. Lu and RAChipman: J.Opt.Soc.Am.A 13 p.1106 (1996); Therefore, the polar angle θ and the azimuth angle φ can be determined with reference to the contents.

In FIG. 1 again, the computer 34 is configured to be able to control the processing conditions applied to the polymer film 12, the polarizing film 18, the polymer film 22, and the laminated body 28a so that Δα becomes zero.
In the example shown in FIG. 1, the polymer film 12 is subjected to a stretching process due to a difference in rotational speed between the rotary rolls 13 and 15 and a process by the processing means 14 and 16 before being laminated with another member. Examples of treatments performed by the treatment means 14 and 16 include saponification treatment and adhesive coating treatment. The stretching process is a process that affects in-plane retardation (Re) and / or retardation in the thickness direction (Rth) of the polymer film. By controlling the stretching ratio and stretching direction of the stretching process, Δα is The Re and / or Rth of the polymer film 12 can be adjusted so as to be zero. The saponification treatment and the pressure sensitive adhesive coating treatment are treatments mainly for the purpose of improving adhesiveness for bonding to the polarizing film, and these treatments are also performed for Re and / Rth of the polymer film. Therefore, by controlling the conditions of these treatments, Re and / or Rth of the polymer film 12 can be adjusted so that Δα becomes zero.

Specific examples of control of the processing conditions of the polymer films 12a and 12b are listed below by way of examples of stretching treatment, saponification treatment, and adhesive coating treatment, but are not limited thereto.
(1) Based on the value of Δα, the rotational speed of the rotating rolls 13 and 15 is controlled, and the stretching ratio of the stretching treatment applied to the polymer film 12a is adjusted, so that the polymer film 12a becomes 0 so that Δα becomes zero. The retardation (Re and / or Rth) is increased or decreased.
(2) Based on the value of Δα, the treatment conditions for the saponification treatment performed by the treatment means 14, such as treatment time, treatment temperature (which may be either liquid temperature or atmospheric temperature), and saponification treatment solution The base concentration is controlled, and the retardation (Re and / or Rth) of the polymer film 12b is increased or decreased so that Δα becomes zero. Specifically, the processing time is controlled by controlling the rotational speed of the rotary rolls 13 and 15; the processing temperature is controlled by ON / OFF control of heaters and coolers, control for raising and lowering the temperature setting, and the saponification treatment. The base concentration of the liquid can be controlled by ON / OFF control of the supply mechanism of water or basic substance into the processing liquid tank, control for increasing or decreasing the supply amount, and the like.
(3) Based on the value of Δα, the processing conditions of the pressure-sensitive adhesive application processing performed by the processing means 16, such as processing time, processing temperature (any of pressure-sensitive adhesive temperature and atmospheric temperature), pressure-sensitive adhesive The retardation (Re and / or Rth) of the polymer film 12c is increased or decreased so that the concentration, the coating amount, and the drying time are controlled and Δα becomes zero. Specifically, the processing time is controlled by controlling the rotational speed of the rotary rolls 13 and 15; the processing temperature is controlled by ON / OFF control of heaters and coolers, control for raising and lowering the temperature setting, etc .; Is controlled by ON / OFF control of a supply mechanism of a solvent such as water to the adhesive coating solution tank and the adhesive, and a control for increasing / decreasing the supply amount; , The rotation speed of the pressure roll 26), and the control for increasing or decreasing the supply amount of the adhesive to the coater.

  Examples of the treatment performed by the treatment means 14 or 16 include surface activation treatment such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, and electron beam irradiation treatment. These surface activation treatments are mainly performed to improve the adhesion to the polarizing film, as in the saponification treatment, but also affect the Re and / or Rth of the polymer film as in the saponification treatment. By controlling the conditions, Re and / or Rth of the polymer films 12a and 12b may be adjusted so that Δα becomes zero. Specifically, the control of the output of the light beam used for the surface activation process, the control of the processing time, and the like.

  In the example shown in FIG. 1, the polarizing film 18 is processed by the processing means 20 before being laminated with another member. Examples of the processing means applied by the processing means 20 include an adhesive application process. The adhesive coating process on the polarizing film is a process that affects Re and / or Rth after the lamination of the polymer film 12 and the polymer film 22 to be laminated. In FIG. 1, by controlling the treatment conditions, The Re and / or Rth of the polymer film 12 or 22 after lamination is configured to be adjustable so that Δα becomes zero. A specific control method is the same as the above-described control method of the processing conditions of the adhesive coating process applied to the polymer film 12b by the processing means 16. Moreover, the process performed on the polarizing film 18 by the processing means 20 may be a process that affects the degree of polarization of the polarizing film, and may be a stretching process, for example.

  In the example shown in FIG. 1, the polymer film 22 is processed by the processing means 24 before being laminated with another member. Examples of the processing means performed by the processing means 24 include a stretching process, a saponification process, the surface activation process, and an adhesive application process, and a plurality of processes selected from these processes may be performed. As described above, these treatments are treatments that affect the Re and / or Rth of the polymer film 22, and by controlling the treatment conditions, the Re and / or Rth of the polymer film 22 is reduced to 0 by Δα. It is comprised so that adjustment is possible. A specific control method is the same as the above-described control method of the processing conditions of each processing performed on the polymer film 12 by the rotating rolls 13 and 15 and the processing means 14 and 16.

  In the example shown in FIG. 1, the pressure applied to the nip portion by the pair of pressure rolls 26 and the feed speed (pressurization time) by the pressure rolls 26 can be controlled based on Δα. The polymer film 12 c, the polarizing film 18 b, and the polymer film 22 b are pressed by the pressure roll 26 in a state where the polymer film 12 c, the polarizing film 18 b, and the polymer film 22 b are stacked, thereby forming an integrated laminate 28 a. The pressure at the time of bonding and the pressurizing time are controlled so that Δα becomes zero. Furthermore, in the example shown in FIG. 1, the laminated body 28 a is processed by the processing means 30. Examples of the processing performed by the processing means 30 include heat drying processing. The drying temperature and drying time affect the Re and / or Rth of the laminated polymer film 12c and the polymer film 22b, and also the degree of polarization of the laminated polarizing film 18b. Therefore, Δα is 0. The drying time and drying temperature may be controlled so that

  In addition, for example, part or all of the manufacturing process may be performed in a compartment with adjustable temperature and humidity, and in that case, the temperature and / or humidity in the compartment may be controlled based on Δα. .

  The laminate 28b is measured in a predetermined characteristic value by the detector 32, and then wound into a roll as a long polarizing plate 28, and is transported and stored. After that, it is cut into a desired size according to the application and incorporated into a liquid crystal display device or the like.

  The manufacturing method of the present invention is not limited to the example shown in FIG. In FIG. 1, the control unit 14, 16, 20, 24, 30, the rotating rolls 13, 15, and the pair of pressure rolls 26 are shown to be controllable, but at least one processing condition is set. What is necessary is just to comprise so that control is possible. Further, it is not necessary to include all processing steps for each of the polymer film 12, the polarizing film 18, the polymer film 22, and the laminate 28a, and at least one processing step for the polymer film 12, the polarizing film 18, the polymer film 22, and the laminate 28a. As long as the processing condition of the processing step is controlled based on Δα, it is within the scope of the present invention.

  In the example shown in FIG. 1, α of the laminated body 28 b is measured, but α of the laminated body 28 a before being processed by the processing means 30 may be measured. However, in that case, the treatment performed by the treatment means 30 is preferably a treatment that does not affect the Re and Rth of the polymer film 12c and the polymer film 22b.

Further, in the example shown in FIG. 1, α of the laminate 28b obtained by laminating three pieces of the polymer film 12c, the polarizing film 18b, and the polymer film 22b is measured. For example, the α of the polymer film 12c and the polymer film 22b is measured. When one side and the laminated body which laminated | stacked the polarizing film 18b previously are produced once, and then the other is laminated | stacked, it replaces with or in addition to the measurement of (alpha) of the laminated body 28b, polymer film 12c or 22b, and polarizing film 18b May be measured, a difference Δα ′ from a predetermined design value α ₀ ′ may be calculated, and the conditions of the processing step may be controlled based on the value of Δα ′.

  The polarizing plate manufactured by the manufacturing method of the present invention is not limited to a polarizing plate having a three-layer structure. It is also useful as a method for producing a polarizing plate having a laminated polymer film as one or both protective films. As the polymer film having a laminated structure, for example, a polymer film as a support and a polymer film having an optically anisotropic layer formed from a liquid crystal composition thereon, or a laminate of two or more polymer films, etc. It may be a form. In the former aspect, the conditions for forming the optically anisotropic layer may be controlled based on Δα. Controllable conditions in the formation process of the optically anisotropic layer include liquid crystal composition coating conditions (such as the composition and coating amount of the liquid crystal composition), alignment processing conditions (such as alignment temperature and alignment time), and immobilization treatment. Conditions (temperature, irradiation energy such as ultraviolet rays, irradiation time, etc.).

It is a schematic diagram which shows an example of the manufacturing method of this invention. It is a schematic diagram used in order to explain a part of process of an example of a manufacturing method of the present invention.

Explanation of symbols

12, 12a, 12b, 12c, 22, 22a, 22b Polymer film 13, 15 Rotating rolls 14, 16, 20, 24, 30 Processing means 18, 18a, 18b Polarizing film 26 Pair of pressure rolls 28 Polarizing plates 28a, 28b Laminate 32 Detector 34 Computer

Claims (12)

The following (a) to (c):
(A) preparing a long polymer film that has not been treated or at least subjected to a first treatment;
(B) preparing a long polarizing film that has not been processed or at least subjected to the second processing;
(C) Bonding at least the long polymer film prepared in (a) and the long polarizing film prepared in (b) to obtain a long laminate;
Is a method for producing a polarizing plate continuously,
(D) obtaining at least one characteristic value α indicating the polarization characteristics of the long laminate obtained in (c);
(E) comparing the characteristic value α obtained in (d) with a predetermined design value α ₀ ;
(F) Based on the comparison in (e), at least one condition of at least one process selected from the first process in (a), the second process in (b), and the bonding process in (c) To control,
The manufacturing method of the polarizing plate characterized by including. The method according to claim 1, wherein the characteristic value α is the dichroic vector D and / or the polarization vector P of the laminate. In (e), the difference ΔD between the dichroic vector D of the laminate and the design value D ₀ of the dichroic vector, and / or the polarization ability vector P of the laminate and the depolarization design value DP ₀ The method according to claim 2, wherein the difference ΔDP is calculated. In (d), a dual rotation retarder type polarimeter is used to detect the polarized light that has passed through the laminate, and the dichroism vector D and / or polarization ability vector P of the laminate is calculated from the detected value. The method according to claim 2 or 3, characterized in that: In (d), the polarization state of the light incident from the direction inclined by the polar angle θ (0 ° <θ <90 °) with respect to the surface of the laminate is detected, and the dichroic vector D and 5. The method according to claim 4, wherein a polarization vector P is calculated. In (d), the incident light is incident from a direction inclined by a polar angle θ with respect to the surface of the laminate in the direction of the azimuth angle φ (0 ° <φ <90 °) with reference to the longitudinal direction of the long laminate. 6. The method according to claim 5, wherein a polarization state of light is detected, and a dichroism vector D and / or a polarization ability vector P is calculated from the detected value. In (d), the characteristic value of the laminated body which has a polymer film in each of a polarizing film and its both surfaces is obtained at least, The method of any one of Claims 1-6 characterized by the above-mentioned. The first treatment is a treatment that affects in-plane retardation and / or retardation in the thickness direction of the polymer film, and in (f), at least one condition of the first treatment is controlled. The method according to claim 1, wherein the method is characterized in that The method according to claim 8, wherein the first treatment is at least one treatment selected from a saponification treatment, a stretching treatment, and an adhesive coating treatment. In (a), a polymer film subjected to at least saponification treatment is prepared, and in (f), at least one condition selected from the saponification treatment time, temperature, and base concentration of the treatment liquid is controlled. The method according to any one of claims 1 to 9. The polymer film subjected to at least stretching treatment is prepared in (a), and the stretching ratio of the stretching treatment is controlled in (f), according to any one of claims 1 to 10. Method. In (a), a polymer film subjected to at least an adhesive coating treatment is prepared, and / or in (b), a polarizing film subjected to at least an adhesive coating treatment is prepared, and in (f), ( The pressure-sensitive adhesive coating treatment time, temperature, pressure-sensitive adhesive concentration, coating amount, and drying time in a) and / or (b) are controlled. 2. The method according to item 1.

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