TW202122839A - Polarizing film laminate with adhesive layer and optical display panel in which said polarizing film laminate with adhesive layer is used - Google Patents

Abstract

The present invention provides: a polarizing film laminate which is capable of comprehensively solving the problems of polyene formation, decoloration and red discoloration by heating; and the like. A polarizing film laminate with an adhesive layer comprising a polarizing film that contains a polyvinyl alcohol resin and an adhesive layer that is provided on at least one surface of the polarizing film directly or with an optically transparent polarizing film protection film being interposed therebetween, wherein: the adhesive layer contains an adhesive polymer; the adhesive polymer has a copolymerized acid component; and the amount of the acid component in all monomer components in the adhesive polymer is 5% by weight or less. In an x-y rectangular coordinate system in which the iodine concentration in the polarizing film is taken on the x-axis and the moisture content in the polarizing film laminate is taken on the y-axis, this polarizing film laminate with an adhesive layer has an iodine concentration and a moisture content within the region bounded by: a first line segment that connects a first coordinate point where the iodine concentration is 7.0 wt% and the moisture content is 0.7 g/m2 and a second coordinate point where the iodine concentration is 2.2 wt% and the moisture content is 3.2 g/m2; a second line segment that connects the second coordinate point and a third coordinate point where the iodine concentration is 2.2 wt% and the moisture content is 4.0 g/m2; a third line segment that connects the third coordinate point and a fourth coordinate point where the iodine concentration is 3.0 wt% and the moisture content is 4.0 g/m2; a fourth line segment that connects the fourth coordinate point and a fifth coordinate point where the iodine concentration is 10.0 wt% and the moisture content is 0.7 g/m2; and a fifth line segment that connects the first coordinate point and the fifth coordinate point.

Description

Adhesive layer-attached polarizing film laminate, and optical display panel using the adhesive layer-attached polarizing film laminate

The present invention relates to a polarizing film laminate with an adhesive layer and an optical display panel using the polarizing film laminate with the adhesive layer.

In recent years, optical display panels such as liquid crystal panels and organic EL panels can be used in electronic devices such as smartphones, personal computers, and electrical appliances such as IoT home appliances, as well as various types of power vehicles such as automobiles, trams, and airplanes. possibility. For example, it is considered that the windshield, dashboard, exterior, and other various parts of the car body are equipped with optical display panels to provide various information to the driver or to transmit various information to the outside.

However, unlike smartphones, powered vehicles are mostly used in harsh outdoor environments. For example, use environments such as high temperature or high humidity will cause optical display panels, especially polarizing film laminates for optical display panels. The performance of the polarizing film (polarizing plate) and the polarizing film (polarizing member) used for the polarizing film laminate is deteriorated, and in the worst case, it may become unusable.

Patent Document 1 discloses an example of a polarizer that has improved durability in a high temperature or high humidity environment, a polarizer using the polarizer, and a liquid crystal display device using the polarizer. In terms of durability, the problem here is that when placed under high temperature conditions, red light (polarized light transmission of long-wavelength light) will be generated under cross-polarized light. In order to solve this problem, it is proposed to make it contain zinc. The zinc content is adjusted to a predetermined range according to the relationship with the iodine content.

Similarly, Patent Document 2 relates to a polarizing plate used in an in-vehicle image display device that has improved durability in a high-temperature or high-humidity environment, and focuses on the moisture content of the polarizing plate and the saturated water absorption of the protective film. Polarizers for automotive use require high-temperature durability. However, under high-temperature environments, polarizers may have a significant decrease in transmittance due to polyolefinization. In order to solve this problem, Patent Document 2 proposes the use of saturated water absorption. Those within a predetermined range are used as a transparent protective film attached to the polarizer and a method to reduce the moisture content of the polarizer.

Patent Document 3 also relates to a polarizing plate that has improved durability under high temperature or high humidity, and here focuses on the moisture content of the polarizing plate and the moisture permeability of the protective film. In high temperature environments, etc., the inside of the polarizing plate will become high temperature and high humidity. As a result, the amount of change in light transmittance, polarization, and image color will increase, and the reliability of the polarizing plate will decrease. Therefore, it is proposed A method of laminating a protective film with low moisture permeability in a state where the moisture content of the polarizer has been reduced as much as possible. Prior art literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. 2003-29042 Patent Document 2: Japanese Patent Laid-Open No. 2014-102353 Patent Document 3: Japanese Patent Laid-Open No. 2002-90546

The problem to be solved by the invention Regarding optical display panels, especially polarizing film laminates used in optical display panels or polarizing films used in polarizing film laminates, it is known that the problems that occur under high temperature or high humidity are "polyolefinization" and "fading". ", and "Red change on heating".

It is generally known that the so-called "polyolefinization" refers to the phenomenon that the monomer transmittance of the polarizing film laminate is reduced due to the high temperature or high humidity environment; in addition, the so-called "fading" and "heating red change" refer to the same Due to the high temperature or high humidity environment, when the polarizing film laminate is arranged into cross-polarized light and the cross-transmittance at the wavelength of 410nm and 700nm is measured, the cross-transmittance increases; and "fading" especially refers to The long-wavelength side of about 700nm and the short-wavelength side of about 410nm increase in transmittance and the phenomenon of fading under black display. On the other hand, "heating red change" especially refers to the increase of transmittance on the long-wavelength side of about 700nm. The phenomenon that the color of the polarizing film turns red.

Patent document 1 mainly focuses on the problem of "fading", patent document 2 mainly focuses on the problem of "polyolefinization", patent document 3 mainly focuses on the problem of "heating redness", and the solutions proposed in each document are at least It is effective for solving individual problems. However, the inventions described in various patent documents are not necessarily sufficient to solve these problems in a comprehensive manner. "Polyolefin", "fading" and "heating red change" are all related to each other through iodine and moisture, and even through the temperature and humidity that affect moisture. Based on this fact, after repeated active research, this The patent applicant obtained the following insights: By adjusting the iodine concentration of the polarizing film and the moisture content of the polarizing film laminate, these problems can be solved in a comprehensive manner. The purpose of the present invention is to attempt to adjust the iodine concentration of the polarizing film and the moisture content of the polarizing film laminate to solve these three problems in a comprehensive manner.

When attaching a polarizing film to a liquid crystal cell, etc., an adhesive is usually used. In addition, since the adhesive has the advantages of instantly fixing the polarizing film to the liquid crystal cell, etc., and no drying step is required when fixing the polarizing film to the liquid crystal cell, etc., most of them are pre-installed on the polarizing film in the form of an adhesive layer. The one-sided. That is, to attach a polarizing plate, a polarizing plate with an adhesive layer is generally used.

The characteristics required for the adhesive layer include: Adhesiveness does not decrease over time and high durability; when the polarizing film is bonded to the liquid crystal cell, even if the bonding position is wrong or the bonding surface is mixed In the case of foreign matter, the polarizing film can still be peeled from the surface of the liquid crystal panel and re-attached (heavy work), etc.

When an optical display panel is used in a powered vehicle, high-temperature durability is also required for an adhesive used to attach a polarizing film constituting the optical display panel to a liquid crystal cell or the like. For the purposes described above, monomer components of the adhesive polymer containing acid components such as acrylic acid can be suitably used as the adhesive composition constituting the adhesive.

The inventors of the present invention have discovered that a new problem of deterioration of polyolefination occurs due to the acid component copolymerized in the adhesive polymer. In the above-mentioned prior art, although the polyolefinization of the polarizing film is discussed, the durability or rework of the adhesive layer has not been discussed, and there is no disclosure on the subject.

The purpose of the present invention is to provide a polarizing plate with an adhesive layer with an adhesive layer on the polarizing film directly or through an optically transparent polarizing film protective film, so as to obtain the reliability of the optical characteristics, the adhesion durability, and the rework Good sex.

Means to solve the problem The present inventors focused on the influence of the acid component in the monomer component of the adhesive polymer contained in the adhesive layer on the performance of the polarizing film, thereby completing the present invention. In the prior art, regarding the adhesive polymer contained in the adhesive layer, the ratio of the acid component that is not in the monomer component at all, the reliability of the optical properties or the adhesion durability, heavy-duty and other polarizing films attached to the adhesive layer Discuss from the viewpoint of the relevance of the performance of the laminate. The inventors of the present invention have discovered the amount of acid components in the total monomer components of the adhesive polymer required to obtain an adhesive layer-attached polarizing film laminate having excellent characteristics.

It is generally believed that when the monomer component of the adhesive polymer contains acid components such as acrylic acid, the hydrogen bonding of the COOH group of the acid component can improve the high temperature durability, but the acid component will serve as the polyvinyl alcohol (PVA) that constitutes the polarizing film. The dehydration condensation catalyst of the resin film plays a role to promote polyalkylene; but it is not limited by any theory.

In order to solve the above-mentioned problems, the polarizing film laminate of an adhesive layer with a polarizing film laminate system of one aspect of the present invention is provided with a polarizing film containing a polyvinyl alcohol-based resin, and an adhesive layer, and the adhesive layer is directly Or set on at least one side of the polarizing film through an optically transparent polarizing film protective film; the polarizing film laminate has the following characteristics: the adhesive layer contains an adhesive polymer, and the acid component in the adhesive polymer is co- Polymerization, and the amount of the acid component in the total monomer components constituting the adhesive polymer is less than 5 wt%; let the x-axis be the iodine concentration (wt.%) of the aforementioned polarizing film and the y-axis be the aforementioned In the xy orthogonal coordinate system of the moisture content (g/m ² ) of the polarizing film laminate, there is an iodine concentration and moisture content included in the area surrounded by the following line segment: connecting the iodine concentration 7.0wt.% and the moisture content 0.7g the first line / m ² of a first coordinate point and the iodine concentration 2.2wt.% and the amount of water 3.2g / m 2 of the second coordinate point ^2, the second connecting point and the coordinate iodine concentration 2.2wt.%, and water content 4.0 the second segment g / m ² of a third coordinate point connecting point and the third coordinate iodine concentration 3.0wt.% and the amount of water 4.0g / m ² of a fourth coordinate point of the third line segment connecting the fourth coordinate Point and the fourth line segment of the fifth coordinate point with an iodine concentration of 10.0 wt.% and a moisture content of 0.7 g/m ² , and a fifth line segment connecting the aforementioned first coordinate point and the aforementioned fifth coordinate point. According to this aspect, the adhesive layer-attached polarizing film film laminate can comprehensively solve the problems of "polyolefinization", "fading", "heating redness", "adhesion durability" and "heavy work".

In the polarizing film film laminate of the above aspect, the polydispersity index (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the adhesive polymer may be 3.0 or less. This is the same in (yet) another aspect related to the present invention.

In the polarizing film thin film laminate of the above aspect, the film thickness of the polarizing film may be 4-20 μm.

In addition, another aspect of the polarizing film laminate of the present invention is a polarizing film laminate with an adhesive layer, which includes a polarizing film containing a polyvinyl alcohol-based resin, and an adhesive layer, and the adhesive layer is directly Or set on at least one side of the polarizing film through an optically transparent polarizing film protective film; the polarizing film laminate has the following characteristics: the adhesive layer contains an adhesive polymer, and the acid component in the adhesive polymer is co- Polymerization, and the amount of the acid component in the total monomer components constituting the adhesive polymer is less than 5 wt%; let the x-axis be the iodine concentration (wt.%) of the aforementioned polarizing film and the y-axis be the aforementioned In the xy orthogonal coordinate system of the moisture content (g/m ² ) of the polarizing film laminate, there is an iodine concentration and moisture content included in the area surrounded by the following line segment: connecting the iodine concentration 4.5wt.% and the moisture content 2.0g /m ² of the 6th coordinate point with the iodine concentration of 2.2wt.% and the moisture content of 3.2g/m ² of the second coordinate point of the 6th line segment connecting the aforementioned second coordinate point with the iodine concentration of 2.2wt.% and the moisture content of 4.0 the second segment g / m ² of a third coordinate point connecting point and the third coordinate iodine concentration 3.0wt.% and the amount of water 4.0g / m ² of a fourth coordinate point of the third line segment connecting the fourth coordinate Point and the seventh line segment of the seventh coordinate point with an iodine concentration of 4.5 wt.% and a moisture content of 3.3 g/m ² , and the eighth line segment connecting the aforementioned sixth coordinate point and the aforementioned seventh coordinate point.

In the polarizing film laminate of the above aspect, the sixth coordinate point may be a coordinate point with an iodine concentration of 4.0wt.% and a moisture content of 2.3g/m ² , and the seventh coordinate point may also be a coordinate point with an iodine concentration of 4.0wt. .% and the coordinate point of the water content of 3.5g/m ^2.

In the polarizing film thin film laminate of the above aspect, the film thickness of the polarizing film may also be 11-20 μm.

In yet another aspect of the present invention, the polarizing film laminate of the polarizing film laminate system with an adhesive layer is provided with a polarizing film containing a polyvinyl alcohol-based resin, and an adhesive layer, the adhesive layer being directly or interposed An optically transparent polarizing film protective film is provided on at least one side of the polarizing film; the polarizing film laminate has the following characteristics: the adhesive layer includes an adhesive polymer, and the acid component in the adhesive polymer is copolymerized, and The amount of the acid component in the total monomer components constituting the adhesive polymer is less than 5% by weight; the x-axis is the iodine concentration (wt.%) of the aforementioned polarizing film, and the y-axis is the aforementioned polarizing film laminate. The xy orthogonal coordinate system of the water content of the body (g/m ² ) has the iodine concentration and water content included in the area surrounded by the following line segment: connecting the iodine concentration 7.0wt.% and the water content 0.7g/m ² the first coordinate point and the iodine concentration 3.0wt.% and the amount of water 2.6g / m ² of the coordinate points of the eighth segment 11, connecting said first coordinate point and 8 iodine concentration 6.0wt.% and the amount of water 2.6g / m ² The 10th line segment of the 9th coordinate point, the 12th line connecting the aforementioned 9th coordinate point with the iodine concentration of 10.0wt.% and the moisture content of 0.7g/m ² of the 5th coordinate point, and the aforementioned first coordinate point with The 5th line segment of the aforementioned 5th coordinate point. According to this aspect, the adhesive layer-attached polarizing film film laminate can comprehensively solve the problems of "polyolefinization", "fading", "heating redness", "adhesion durability" and "heavy work".

In the above aspect of the polarizing film laminate, the 8th coordinate point may be the 6th coordinate point with an iodine concentration of 4.5wt.% and a moisture content of 2.0g/m ² , and the 9th coordinate point may also be the iodine concentration The 10th coordinate point of 7.2wt.% and moisture content of 2.0g/m ^2.

In addition, in the polarizing film thin film laminate of the above aspect, the film thickness of the polarizing film may be 4 to 11 μm.

In addition, in the polarizing film thin film laminate of the above aspect, the polarizing film preferably contains zinc.

In addition, with regard to the polarizing film laminate of the above aspect, a sample composed of a polarizing film laminate and a glass plate laminated on both sides of the polarizing film laminate through an adhesive was heated at 95°C/500 hours. The volume transmittance is preferably the same as or greater than the monomer transmittance before heating. In this way, the problem of polyolefination can be effectively solved.

Regarding the polarizing film laminate of the above aspect, a sample composed of a polarizing film laminate and a glass plate laminated on both sides of the polarizing film laminate with a transparent adhesive is heated at 95°C/500 hours, and the wavelength The change in orthogonal transmittance at 410nm should be less than 1%, and the change in orthogonal transmittance at a wavelength of 700nm should be less than 5%. In this way, the problem of fading can be effectively solved.

Regarding the polarizing film laminate of the above aspect, a sample composed of a polarizing film laminate and a glass plate laminated on both sides of the polarizing film laminate with a transparent adhesive is heated at 95°C/500 hours, and the wavelength The change in the orthogonal transmittance at 410nm should be more than 1%, and the change in the orthogonal transmittance at a wavelength of 700nm should be less than 5%. In this way, the problem of heating redness can be effectively solved.

The polarizing film film laminate of the above aspect may be provided with an anti-reflection layer on the viewing side of the polarizing film via a base material, and the moisture permeability of the anti-reflection film composed of the base material and the anti-reflection layer may be 15g/m ²・24h or more.

In addition, the polarizing film thin-film laminate of the above aspect preferably includes: a liquid crystal cell having a liquid crystal layer and the liquid crystal layer contains liquid crystal molecules aligned in one direction in the plane without applying an electric field; the first polarizing film is arranged On one side of the liquid crystal cell; and a second polarizing film, arranged on the other side of the liquid crystal cell so that the absorption axis is orthogonal to the absorption axis of the first polarizing film; and on the first polarizing film and the liquid crystal cell In between, a first retardation layer and a second retardation layer are arranged in order from the side of the first polarizing film, and the refractive index of the first retardation layer in the slow axis x direction in the plane is nx1, fast When the refractive index in the axial direction is ny1 and the refractive index in the thickness z direction is nz1, the relationship of nx1>ny1>nz1 is satisfied; When the refractive index in the axial direction is ny2 and the refractive index in the thickness z direction is nz2, the relationship of nz2>nx2≧ny2 is satisfied.

In addition, the polarizing film thin-film laminate of the above aspect preferably includes: a liquid crystal cell having a liquid crystal layer and the liquid crystal layer contains liquid crystal molecules aligned in one direction in the plane without applying an electric field; the first polarizing film is arranged On one side of the liquid crystal cell; and a second polarizing film, arranged on the other side of the liquid crystal cell so that the absorption axis is orthogonal to the absorption axis of the first polarizing film; and on the first polarizing film and the liquid crystal cell In between, a first retardation layer and a second retardation layer are arranged in order from the side of the first polarizing film, and the refractive index of the first retardation layer in the slow axis x direction in the plane is nx1, fast When the refractive index in the axial direction is ny1 and the refractive index in the thickness z direction is nz1, the relationship of nz1>nx1=ny1 is satisfied; When the refractive index in the axial direction is ny2 and the refractive index in the thickness z direction is nz2, the relationship nx2>ny2=nz2 is satisfied.

Furthermore, the polarizing film thin-film laminate of the above aspect preferably includes: a liquid crystal cell having a liquid crystal layer and the liquid crystal layer contains liquid crystal molecules aligned in one direction in the plane without applying an electric field; and the polarizing film is arranged in One side of the liquid crystal cell; and a retardation layer is arranged between the polarizing film and the liquid crystal cell, and the retardation layer is set such that the refractive index of the slow axis x direction in the plane is nx, the refractive index of the fast axis direction When it is ny and the refractive index in the thickness z direction is nz, the relationship of nx>nz>ny is satisfied.

In addition, in order to solve the above-mentioned problems, an optical display panel of one aspect of the present invention is characterized in that it includes: an optical display unit; a polarizing film laminate such as any one of the above, which is bonded directly or via another optical film One side of the optical display unit; and a cover plate, which is optically transparent and is arranged along the polarizing film laminate on the opposite side of the polarizing film laminate from the optical display unit; and, the optical display The unit, the polarizing film laminate, and the transparent cover plate are bonded by a transparent adhesive layer, and the transparent adhesive layer is filled in a state in which no gaps are generated between them.

In the optical display panel of the above aspect, the transparent cover plate may also have the function of a capacitive touch sensor.

In addition, the optical display panel of the above aspect may also be provided with an ITO layer, which is a constituent element of a capacitive touch sensor, between the transparent cover plate and the polarizing film laminate.

Invention effect According to the present invention, the problems of "polyolefinization", "fading", "heating redness", "adhesion durability" and "heavy industry" can be solved in a comprehensive manner.

The following describes a preferred embodiment of the present invention with reference to the attached drawings. For the convenience of description, only the preferred embodiments are shown, but the present invention should not be limited by this.

The object of the present invention is an optical display panel, especially an optical display panel mounted on the body of an automobile, a tram, an airplane, and other powered vehicles that use power to travel, and a polarizing film laminate used for the optical display panel. Here, the so-called "installed in the car body" does not necessarily refer to the case where the optical display panel or the polarizing film laminate is fixed to the car body. For example, it also includes the optical display panel or the polarizing film laminate used in smartphones, etc. It can be used in such situations as freely carrying and carrying it into a powered traveling vehicle. Furthermore, the so-called "installed on the car body" includes all situations where an optical display panel or a polarizing film laminate is used together with a powered vehicle, and may be exposed to high temperature or high humidity.

1. Optical display panel FIG. 1 is a schematic diagram showing the layer structure of the optical display panel 1. The optical display panel 1 includes at least an optical display unit 10, a polarizing film laminate 12, and a cover plate 14. The polarizing film laminate 12 is laminated on one surface 10a side (viewing side) of the optical display unit 10; the cover plate 14 It is optically transparent and is arranged along the polarizing film laminate 12 on the side of the polarizing film laminate 12 opposite to the optical display unit 10, that is, the viewing side. On the other surface 10 b side of the optical display unit 10, another polarizing film laminate 17 is arranged through the transparent adhesive 16. The optical display unit 10, the polarizing film laminate 12, and the cover plate 14 are connected by layers of transparent adhesives 11, 13, and the layers of transparent adhesives 11, 13 are filled in a state that does not create gaps between them In it. In addition, in this specification, unless otherwise specified, the term "adhesive" includes adhesion (pressure-sensitive adhesive). The optical display unit 10 and the polarizing film laminate 12 can be directly bonded using a transparent adhesive 11, but can also be bonded via other optical films (not shown in the drawings) such as retardation films, viewing angle compensation films, etc., as required.

1-1. Optical display unit Examples of the optical display unit 10 may include a liquid crystal cell or an organic EL cell. The organic EL unit can be suitably used as a light-emitting body (organic electroluminescent body) formed by sequentially layering a transparent electrode, an organic light-emitting layer, and a metal electrode on a transparent substrate. The organic light-emitting layer is a laminate of various organic thin films. For example, the following various layers can be used: a laminate of a hole injection layer composed of triphenylamine derivatives and a light-emitting layer composed of a fluorescent organic solid such as anthracene; A laminate of a light-emitting layer and an electron injection layer composed of a perylene derivative, etc.; or a laminate of a hole injection layer, a light-emitting layer, and an electron injection layer, etc.

The liquid crystal cell can be a reflective liquid crystal cell using external light, a transmissive liquid crystal cell using light from a light source such as the backlight 18, and a semi-transmissive and semi-reflective liquid crystal cell using both external light and light from a light source. Any kind. When the liquid crystal cell uses light from a light source, as shown in FIG. 1, a polarizing film laminate 17 is also arranged on the side opposite to the viewing side of the optical display unit (liquid crystal cell) 10, and for example, a backlight is arranged Like a light source 18. The polarizing film laminate 17 on the light source side and the liquid crystal cell 10 are bonded by a layer of an appropriate transparent adhesive 17. The driving method of the liquid crystal cell may use any type such as VA mode, IPS mode, TN mode, STN mode, or bend orientation (π-type).

1-2. Cover plate Examples of the cover plate 14 can include a transparent plate (window layer) or a touch panel. The transparent board uses a transparent board with appropriate mechanical strength and thickness. As the transparent plate, for example, a transparent resin plate such as acrylic resin or polycarbonate resin, a glass plate, or the like can be used. The surface of the cover plate 14 can also be treated with a low reflection film (not shown in the figure), for example. The touch panel uses various touch panels such as resistive film type, electrostatic capacitance type, optical type, ultrasonic type, etc., or glass plate or transparent resin plate with touch sensing function.

When using a capacitive touch panel as the cover plate 14, it is advisable to provide a front transparent plate made of glass or a transparent resin plate on the side closer to the visibility than the touch panel. In addition, at this time, the transparent adhesive 13 used to join the cover plate 14 and the polarizing film laminate 12 is provided as an ITO layer (not shown in the figure) as a component of the capacitive touch sensor .

[Adhesive composition] It is explained that it can be used in the adhesive composition of the transparent adhesive 11 and the like.

＜Adhesive polymer＞ The adhesive polymer contained in the adhesive composition is not particularly limited as long as it is an adhesive polymer that can generally be used as the base polymer of the adhesive. However, for the reason that the balance of adhesive performance can be easily obtained, Tg is 0. Polymers below °C (usually above -100 °C) are preferred. Among the adhesive polymers, polyester-based polymers, (meth)acrylic-based polymers, and the like can be suitably used. In the adhesive polymer used in the present invention, the acid component is copolymerized.

Polyester-based polymers usually use saturated polyesters or copolyesters of polyols and polycarboxylic acids.

Examples of polyols include ethylene glycol, propylene glycol, hexamethylene glycol, neopentyl glycol, 1,2-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,10-decanediol , 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2-bis(4-hydroxyphenyl)propane, bis(4-hydroxy Diols such as phenyl) sulfite.

Examples of polycarboxylic acids include terephthalic acid, isophthalic acid, phthalic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalene Aromatic dicarboxylic acids such as dicarboxylic acid, diphenylcarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl sulfonic acid, anthracene dicarboxylic acid; 1,3-cyclopentane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid Alicyclic dicarboxylic acids such as carboxylic acid, 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic acid, and hexahydroisophthalic acid; malonic acid, dimethylmalonic acid, succinic acid, 3,3- Diethyl succinic acid, glutaric acid, 2,2-dimethylglutaric acid, adipic acid, 2-methyl adipic acid, trimethyl adipic acid, pimelic acid, azelaic acid, dimer Aliphatic dicarboxylic acids such as acid, sebacic acid, suberic acid, dodecane dicarboxylic acid, etc. Many of the aforementioned polycarboxylic acids are used in combination of two or more kinds of polycarboxylic acids, for example, aromatic dicarboxylic acid and aliphatic dicarboxylic acid are used in combination.

In the present invention, by containing the acid component in the adhesive polymer, the durability of the adhesive can be improved, and the occurrence of foaming or peeling over a long period of time can be prevented. Based on the amount of the total monomer components constituting the adhesive polymer, the upper limit of the amount of acid components is less than 5% by weight, preferably less than 3% by weight, and more preferably less than 2% by weight. If the amount of the acid component exceeds the upper limit, it will adversely affect the polyolefinization of the polarizing film, and the reworkability of the adhesive layer will tend to decrease. Based on the amount of the total monomer components constituting the adhesive polymer, the lower limit of the acid component amount is preferably 0.01% by weight or more, preferably 0.2% by weight or more, and more preferably 0.5% by weight or more. If the amount of acid is small, the durability of the adhesive layer tends to decrease.

Various polyols and polycarboxylic acids used for the polyester-based polymer can be used without particular limitation, and polymer polyols such as polycarbonate diol can be used as the polyol. In addition, the polyester-based polymer can be obtained from the aforementioned diol component and a trivalent or higher polyhydric alcohol and/or a trivalent or higher polycarboxylic acid. The weight average molecular weight of the polyester-based polymer is usually 11,000 or more. The (meth)acrylic polymer usually contains an alkyl (meth)acrylate as a main component as a monomer unit. In addition, the term “(meth)acrylate” means acrylate and/or methacrylate.

The (meth)acrylic acid alkyl ester constituting the main skeleton of the (meth)acrylic polymer may be a linear or branched alkyl group having 1 to 18 carbon atoms. For example, the aforementioned alkyl group can be exemplified by methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, cyclohexyl, heptyl, 2-ethylhexyl, isooctyl, nonyl, Decyl, isodecyl, dodecyl, isomyristyl, lauryl, thirteen, fifteen, sixteen, seventeen, octadecyl, etc. These can be used alone or in combination. The average carbon number of these alkyl groups is preferably 3-9.

In addition, aromatic ring-containing alkyl (meth)acrylates such as phenoxyethyl (meth)acrylate and benzyl (meth)acrylate can be used. The aromatic ring-containing alkyl (meth)acrylate can be used by mixing the polymer obtained by polymerization with the (meth)acrylic polymer exemplified above, but from the perspective of transparency, it contains aromatic The group ring alkyl (meth)acrylate is preferably used by copolymerization with the aforementioned alkyl (meth)acrylate.

In order to improve adhesion and heat resistance, one or more polymerizable functions with unsaturated double bonds such as (meth)acrylic acid groups or vinyl groups can be introduced into the aforementioned (meth)acrylic polymer by copolymerization. -Based comonomers. Specific examples of such comonomers include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and (meth)acrylic acid. 6-hydroxyhexyl ester, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate and (4-hydroxymethylcyclohexyl)-methacrylate Hydroxy-containing monomers such as acrylate; (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid and other carboxyl-containing monomers ; Monomers containing acid anhydride groups such as maleic anhydride and itaconic anhydride; caprolactone adducts of acrylic acid; styrene sulfonic acid or allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropane Sulfonic acid group-containing monomers such as sulfonic acid, (meth)acrylic acid propanesulfonic acid, (meth)acrylic acid sulfopropyl ester, (meth)acrylic acid oxynaphthalene sulfonic acid, etc.; 2-hydroxyethylacrylic acid group Phosphoric acid group-containing monomers such as phosphate esters.

Among the above-mentioned comonomers, the acid component of the present invention includes comonomers having polymerizable functional groups with unsaturated double bonds such as (meth)acrylic groups or vinyl groups. Specific examples of comonomers that are acid components include acrylic acid, (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, Carboxyl group-containing monomers such as crotonic acid; acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; caprolactone adducts of acrylic acid; styrene sulfonic acid or allyl sulfonic acid, 2-(meth)acrylic acid Amino-2-methylpropanesulfonic acid, (meth)acrylamide propanesulfonic acid, sulfopropyl (meth)acrylate, (meth)acryloxynaphthalenesulfonic acid and other sulfonic acid group-containing monomers; 2 -Phosphoric acid group-containing monomers such as hydroxyethyl acryloyl phosphate, etc.

When there is an acid component, from the point of view of the adverse effects caused by the acid, we believe that it should be the acid of a relatively weak acid system such as a carboxyl group-containing monomer, and then it can also be a phosphoric acid group-containing monomer or a sulfonic acid system. Based monomers and so on.

The comonomer used for the purpose of modification can include (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide or N-hydroxymethyl (N-substituted) amide-based monomers such as methyl (meth)acrylamide, N-hydroxymethylpropane (meth)acrylamide, etc.; aminoethyl (meth)acrylate, (meth)acrylic acid-N, N-dimethylaminoethyl, (meth)acrylic acid tertiary butylaminoethyl and other (meth)acrylic acid alkylaminoalkyl ester monomers; (meth)acrylic acid methoxyethyl, (meth)acrylate (Meth)acrylic acid alkoxyalkyl ester monomers such as ethoxyethyl acrylate; N-(meth)acryloyloxymethylene succinimidyl or N-(meth)acryloyl -6-Oxyhexamethylene succinimide, N-(meth)acryloyl-8-oxyoctamethylene succinimide, N-acryloyl mopholin and other succinimides Monomer; N-cyclohexylmaleimide or N-isopropylmaleimide, N-laurylmaleimide or N-phenylmaleimide and other maleimides Monomers; N-methylikonimines, N-ethylikonimines, N-butylikonimines, N-octylikonimines, N-2-ethyl Iconimines such as hexyl iconimines, N-cyclohexyl iconimines, N-lauryl iconimines, etc.

、乙烯基吡

、乙烯基吡咯、乙烯基咪唑、乙烯基

唑、乙烯基嗎福林、N-乙烯基羧酸醯胺類、苯乙烯、α-甲基苯乙烯、N-乙烯基己內醯胺等乙烯基系單體；丙烯腈、甲基丙烯腈等氰基丙烯酸酯系單體；(甲基)丙烯酸環氧丙酯等含環氧基之丙烯酸系單體；聚乙二醇(甲基)丙烯酸酯、聚丙二醇(甲基)丙烯酸酯、甲氧基乙二醇(甲基)丙烯酸酯、甲氧基聚丙二醇(甲基)丙烯酸酯等二醇系丙烯酸酯單體；(甲基)丙烯酸四氫糠酯、氟(甲基)丙烯酸酯、聚矽氧(甲基)丙烯酸酯或2-甲氧基乙基丙烯酸酯等丙烯酸酯系單體等作為改質單體。更可列舉異戊二烯、丁二烯、異丁烯、乙烯基醚等。And vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperidine can also be used

Vinylpyridine

, Vinyl pyrrole, vinyl imidazole, vinyl

Vinyl monomers such as azole, vinylmorpholine, N-vinyl carboxamides, styrene, α-methylstyrene, N-vinyl caprolactam, etc.; acrylonitrile, methacrylonitrile Cyanoacrylate monomers such as glycidyl (meth)acrylate; acrylic monomers containing epoxy groups such as glycidyl (meth)acrylate; polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methacrylate Glycol acrylate monomers such as oxyethylene glycol (meth)acrylate and methoxy polypropylene glycol (meth)acrylate; tetrahydrofurfuryl (meth)acrylate, fluoro(meth)acrylate, Acrylate-based monomers such as polysiloxane (meth)acrylate or 2-methoxyethyl acrylate are used as the modifying monomer. More examples include isoprene, butadiene, isobutylene, vinyl ether, and the like.

In addition, the copolymerizable monomers other than the above may also include silane-based monomers containing silicon atoms. As the silane-based monomer, for example, 3-propylene oxypropyl triethoxy silane, vinyl trimethoxy silane, vinyl triethoxy silane, 4-vinyl butyl trimethoxy silane, 4- Vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloxydecyltrimethoxysilane, 10-propylene Oxydecyl trimethoxysilane, 10-methacrylic oxydecyl triethoxy silane, 10-acrylic oxydecyl triethoxy silane, etc.

In addition, as a comonomer, tripropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and bisphenol A can also be used. Diglycidyl ether di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, neopentylerythritol tri(meth)acrylate, Neopentyl erythritol tetra (meth) acrylate, dineopentaerythritol penta (meth) acrylate, dineopentaerythritol hexa (meth) acrylate, caprolactone modified dineopentaerythritol hexa ( (Meth)acrylic acid ester and other (meth)acrylic acid and polyhydric alcohol esterification products, etc. have two or more (meth)acrylic acid groups, vinyl groups and other unsaturated double bonds multifunctional monomers, or in polyester, ring Polyester (meth)acrylates and epoxy resins in which two or more (meth)acrylic acid groups, vinyl groups, and other unsaturated double bonds are added to the skeleton of oxygen and urethane as the same functional groups as the monomer components. (Meth)acrylate, urethane (meth)acrylate, etc.

Among these comonomers, it is also suitable to use hydroxyl group-containing monomers and carboxyl group-containing monomers from the viewpoints of adhesiveness and durability. A hydroxyl group-containing monomer and a carboxyl group-containing monomer can be used in combination. When the adhesive composition contains a cross-linking agent, these comonomers will become the reaction point of the cross-linking agent. Since hydroxyl group-containing monomers, carboxyl group-containing monomers, etc. have good reactivity with the crosslinking agent between molecules, it is preferable to use these monomers in order to improve the cohesiveness and heat resistance of the resulting adhesive layer. From the viewpoint of heavy workability, a hydroxyl group-containing monomer is preferable, and from the viewpoint of having both durability and heavy workability, a carboxyl group-containing monomer is preferable. The hydroxyl-containing monomer can be used in an amount of about 0.01 to 30% by weight, preferably about 0.03 to 20% by weight, and more preferably about 0.05 to 10% by weight in the total monomer components constituting the adhesive polymer.

In addition to the above, comonomers other than acid components can also be about 0-30% by weight, preferably about 0.1-20%, and more preferably about 0.1-10% in the total monomer components constituting the adhesive polymer. Quantity to use.

The weight average molecular weight (Mw) of the adhesive polymer used in the present invention is preferably 900,000 to 3 million. Considering durability, especially heat resistance, the weight average molecular weight is preferably 1.2 million to 2.5 million. If the weight average molecular weight is less than 900,000, low molecular weight polymer components will increase, which will increase the crosslinking density of the gel (adhesive layer), and consequently the adhesive layer will become harder, impairing the stress relaxation properties. Bad. In addition, if the weight average molecular weight is greater than 3 million, the viscosity will increase and gelation will occur during polymer polymerization, which is not preferable.

The polydispersity index (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the adhesive used in the present invention is preferably below 3.0, more preferably 1.05 to 2.5, and more preferably 1.05 to 2.0. If the polydispersity index (Mw/Mn) is greater than 3.0, there will be more low-molecular-weight polymers. In order to increase the gel fraction of the adhesive layer, a large amount of cross-linking agent will need to be used. Therefore, the remaining cross-linking agent It will react with the already gelled polymer to increase the cross-linking density of the gel (adhesive layer), and then the adhesive layer will become hard, impairing the stress relaxation, which is not good. Moreover, we speculate that if there are more low-molecular-weight polymers and more uncrosslinked polymers or oligomers (sol fraction), under heating and humidification conditions, etc., they will segregate to the adhesion of the adherend. The uncrosslinked polymer near the interface of the agent layer will damage the adhesive layer and cause the adhesive layer to peel off. In addition, the weight average molecular weight and the polydispersity index (Mw/Mn) can be measured by GPC (Gel Permeation Chromatography), and can be obtained from values calculated in terms of styrene.

For the production of the adhesive used in the present invention, known production methods such as solution polymerization, bulk polymerization, emulsion polymerization, and various radical polymerizations can be appropriately selected. In addition, the obtained adhesive polymer may be any of random copolymers, block copolymers, graft copolymers, and the like.

In addition, in the solution polymerization, for example, ethyl acetate, toluene, etc. can be used as the polymerization solvent. As a specific example of solution polymerization, the reaction can be carried out by adding a polymerization initiator under an inert gas flow such as nitrogen, and is generally carried out under reaction conditions of about 50 to 70°C for about 10 minutes to 30 hours. In particular, by shortening the polymerization time to about 30 minutes to 3 hours, the formation of low molecular weight oligomers formed in the late stage of the polymerization can be suppressed, and the polydispersity index (Mw/Mn) can be adjusted below 3.0. Best range.

The polymerization initiator, chain transfer agent, emulsifier, etc. used for radical polymerization are not particularly limited, and can be appropriately selected and used. In addition, the weight average molecular weight of the adhesive polymer can be controlled by the amount of polymerization initiator and chain transfer agent used, and reaction conditions, and the amount of use can be appropriately adjusted according to the type of the polymer.

As the polymerization initiator, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-amidinopropane) dihydrochloride, 2,2'-azobis[2 -(5-Methyl-2-imidazolin-2-yl)propane) dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate, 2,2'-azo Bis(N,N'-dimethylisobutylamidine), 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] hydrate (Wako Pure Chemical Industries, Ltd. Manufacture, VA-057) and other azo initiators, potassium persulfate, ammonium persulfate and other persulfates, bis(2-ethylhexyl)peroxydicarbonate, bis(4-tertiarybutylcyclohexyl) Peroxydicarbonate, di-secondary butyl peroxydicarbonate, tertiary butyl peroxide neodecanoate, tertiary hexyl peroxide trimethyl acetate, tertiary butyl peroxide trimethyl acetate, Dilauryl peroxide, di-n-octyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, bis(4-methylbenzyl) )Peroxide, dibenzyl peroxide, tertiary butyl perisobutyrate, 1,1-di(tertiary hexylperoxy) cyclohexane, tertiary butyl hydroperoxide, peroxide Peroxide-based initiators such as hydrogen, combinations of persulfate and sodium bisulfite, combinations of peroxides and sodium ascorbate, and redox initiators combined with peroxides and reducing agents, etc., but not limited In these.

The aforementioned polymerization initiators can be used alone or in a mixture of two or more, but the overall content relative to 100 parts by weight of the monomer is preferably about 0.005 to 1 part by weight, more preferably about 0.02 to 0.5 part by weight.

In addition, when 2,2'-azobisisobutyronitrile is used as a polymerization initiator to produce the aforementioned weight average molecular weight (meth)acrylic polymer, the amount of polymerization initiator used is relative to the total monomer components. The amount is 100 parts by weight, preferably about 0.06 to 0.2 parts by weight, more preferably about 0.08 to 0.175 parts by weight.

As the chain transfer agent, for example, lauryl mercaptan, glycidyl mercaptan, thioacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolic acid, 2,3-dimercapto -1-propanol and so on. The chain transfer agent may be used singly or in combination of two or more, but the total content is about 0.1 parts by weight or less with respect to 100 parts by weight of the total amount of monomer components.

In addition, examples of emulsifiers used for emulsification polymerization include sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzene sulfonate, polyoxyethylene alkyl ether ammonium sulfate, and polyoxyethylene sulfate. Anionic emulsifiers such as sodium alkyl phenyl ether sodium sulfate, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene-polyoxy Nonionic emulsifiers such as propylene block polymers. These emulsifiers may be used alone or in combination of two or more kinds.

In addition, as reactive emulsifiers, emulsifiers introduced with radical polymerizable functional groups such as propenyl and allyl ether groups, specifically, for example, Aqualon HS-10, HS-20, KH-10, BC-05, BC-10, BC-20 (all made by Daiichi Kogyo Pharmaceutical Co., Ltd.), ADEKA REASOAP SE10N (made by Solectron Chemical Co., Ltd.), etc. Since the reactive emulsifier will be incorporated into the polymer chain after polymerization, it is preferred that it has good water resistance. The amount of emulsifier used is 0.3 to 5 parts by weight relative to 100 parts by weight of the total monomer components, and preferably 0.5 to 1 part by weight from the viewpoint of polymerization stability and mechanical stability.

The adhesive polymer used in the present invention usually uses a weight average molecular weight in the range of 300,000 to 4 million. In consideration of durability, especially heat resistance, a weight average molecular weight of 500,000 to 3 million should be used. And 650,000 to 2 million is better. If the weight average molecular weight is less than 300,000, it is not suitable from the viewpoint of heat resistance. In addition, if the weight average molecular weight exceeds 4 million, the adhesion and adhesiveness will decrease, so it is unfavorable from this point of view. In addition, the weight average molecular weight means a value measured by GPC (Gel Permeation Chromatography) and calculated in terms of polystyrene.

＜Other components in the adhesive composition＞ In addition, the adhesive composition used in the present invention may contain a crosslinking agent. As the crosslinking agent, an organic crosslinking agent or a polyfunctional metal chelate compound can be used. Examples of the organic crosslinking agent include isocyanate-based crosslinking agents, peroxide-based crosslinking agents, epoxy-based crosslinking agents, and imine-based crosslinking agents. Multifunctional metal chelate is a covalent bond or coordinate bond between a multivalent metal and an organic compound. Examples of polyvalent metal atoms include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, Ti, and the like. Examples of the atoms that can be covalently bonded or coordinately bonded in the organic compound include oxygen atoms, and the organic compounds include alkyl esters, alcohol compounds, carboxylic acid compounds, ether compounds, ketone compounds, and the like.

The cross-linking agent is preferably an isocyanate-based cross-linking agent and/or a peroxide-based cross-linking agent. The compound of the isocyanate-based crosslinking agent can include, for example, isocyanates such as toluene diisocyanate, chlorophenyl diisocyanate, tetramethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, etc. Monomers, and isocyanate compounds or trimeric isocyanates, biuret-type compounds formed by addition of these isocyanate monomers with trimethylolpropane, etc., as well as polyether polyols, polyester polyols, and acrylic polyols. Alcohol, polybutadiene polyol, polyisoprene polyol, etc. are urethane prepolymer isocyanate formed by addition reaction, etc. Particularly preferred is a polyisocyanate compound, and is one selected from the group consisting of hexamethylene isocyanate, hydrogenated xylylene diisocyanate, and isophorone diisocyanate, or a polyisocyanate compound derived therefrom. Here, one selected from the group consisting of hexamethylene isocyanate, hydrogenated xylylene diisocyanate and isophorone diisocyanate or polyisocyanate compounds derived therefrom include: hexamethylene isocyanate, Hydrogenated xylylene diisocyanate, isophorone diisocyanate, polyol modified hexamethylene isocyanate, polyol modified hydrogenated xylylene diisocyanate, trimer type hydrogenated xylylene diisocyanate and polyol modified iso Phosphonone diisocyanate and so on. The exemplified polyisocyanate compound is ideal because the reaction with the hydroxyl group proceeds rapidly (especially, the acid and alkali contained in the polymer are made to act like catalysts), and are particularly useful for accelerating crosslinking.

The peroxide-based crosslinking agent can be suitably used as long as it generates free radical active species upon heating or light irradiation to crosslink the base polymer of the adhesive composition. However, considering workability and stability, it is suitable to use Peroxides with a 1-minute half-life temperature of 80℃~160℃ are more suitable for peroxides with a temperature of 90℃~140℃.

Peroxides that can be used as crosslinking agents include bis(2-ethylhexyl)peroxydicarbonate (1 minute half-life temperature: 90.6℃), bis(4-tertiarybutylcyclohexyl)peroxydicarbonate Carbonate (1 minute half-life temperature: 92.1°C), peroxydicarbonate di-secondary butyl ester (1 minute half-life temperature: 92.4°C), peroxyneodecanoic acid tertiary butyl ester (1 minute half-life temperature: 103.5°C) , Trimethyl acetate tertiary hexyl peroxide (1 minute half-life temperature: 109.1 ℃), trimethyl peroxide tertiary butyl acetate (1 minute half-life temperature: 110.3 ℃), dilaurin peroxide (1 Minute half-life temperature: 116.4℃), di-n-octyl peroxide (1 minute half-life temperature: 117.4℃), 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (1 Minute half-life temperature: 124.3°C), bis(4-methylbenzyl) peroxide (1 minute half-life temperature: 128.2°C), dibenzyl peroxide (1 minute half-life temperature: 130.0°C), Tertiary butyl perisobutyrate (1 minute half-life temperature: 136.1°C), 1,1-bis(tertiary hexylperoxy) cyclohexane (1 minute half-life temperature: 149.2°C), etc. Among them, especially from the viewpoint of excellent crosslinking reaction efficiency, there are bis(4-tertiarybutylcyclohexyl) peroxydicarbonate (1 minute half-life temperature: 92.1°C), dilaurin peroxide (1 One-minute half-life temperature: 116.4°C), dibenzoyl peroxide (1-minute half-life temperature: 130.0°C), etc.

In addition, the half-life of peroxide is an index indicating the decomposition rate of peroxide, which means the time when the residual amount of peroxide becomes half. Regarding the decomposition temperature required to reach the half-life at any time, or the half-life time at any temperature, it is recorded in the manufacturer’s catalog, for example, in the "Organic Peroxide Catalog No. 9" of NOF Corporation. Edition (May 2003)" and so on.

Relative to 100 parts by weight of the adhesive polymer, the amount of crosslinking agent used is preferably 0.01-20 parts by weight, more preferably 0.03-10 parts by weight. In addition, when the crosslinking agent is less than 0.01 parts by weight, the cohesive force of the adhesive tends to be insufficient, and foaming may occur during heating; on the other hand, if it is more than 20 parts by weight, the moisture resistance is insufficient , And it is easy to peel off during reliability tests.

The above-mentioned isocyanate-based crosslinking agent may be used alone or in combination of two or more, but the total content is preferably 0.01-2 parts by weight of the aforementioned polyisocyanate-based compound relative to 100 parts by weight of the aforementioned adhesive polymer. The content is preferably 0.02 to 2 parts by weight, more preferably 0.05 to 1.5 parts by weight. A cross-linking agent can be appropriately included in consideration of cohesive force and prevention of peeling in the durability test.

The aforementioned peroxide can be used alone or in a mixture of two or more. However, the total content is 0.01 to 2 parts by weight relative to 100 parts by weight of the aforementioned adhesive polymer, and preferably contains 0.04 parts by weight. ~1.5 parts by weight, more preferably 0.05~1 parts by weight. It can be appropriately selected within this range to adjust processability, reworkability, crosslinking stability, releasability, and the like.

In addition, as a method for measuring the amount of peroxide decomposition remaining after the reaction treatment, it can be measured by, for example, HPLC (High Performance Liquid Chromatography).

More specifically, for example, about 0.2 g of the post-reaction adhesive composition is taken out each time, immersed in 10 ml of ethyl acetate, and subjected to shaking extraction with a shaker at 25° C. and 120 rpm for 3 hours, and then statically at room temperature. Set for 3 days. Next, add 10 ml of acetonitrile, shake at 120 rpm for 30 minutes at 25°C, and pour about 10 μl of the extract obtained by filtration with a membrane filter (0.45 μm) into HPLC for analysis, which can be used as the amount of peroxide after the reaction treatment.

The additive is particularly preferably mixed with a silane coupling agent. Silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane Silane and other silicon compounds with epoxy structure; 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)3-aminopropyltrimethoxysilane, N-(2-aminoethyl)3-aminopropyl Amino-containing silicon compounds such as methyl dimethyl dimethyl siloxane; 3-chloropropyl trimethoxy silane; trimethoxy silyl containing acetyl acetyl group, 3-propenyl oxy propyl trimethoxy silane, 3-methyl Silane coupling agents containing (meth)acrylic acid groups such as acryloxypropyl triethoxysilane; silane coupling agents containing isocyanate groups such as 3-isocyanate propyl triethoxysilane. In particular, 3-glycidoxypropyltrimethoxysilane and trimethoxysilane containing acetylacetoxy group can effectively inhibit peeling, so it is suitable for use. Silane coupling agent can impart durability, especially the effect of inhibiting peeling in a humidified environment. Relative to 100 parts by weight of the adhesive polymer, the amount of the silane coupling agent used is 1 part by weight or less, more preferably 0.01 to 1 part by weight, and even more preferably 0.02 to 0.6 part by weight. If the amount of silane coupling agent used increases, the adhesive force to the liquid crystal cell will increase excessively, which may affect the reworkability.

In addition, the adhesive composition used in the present invention may contain other well-known additives. For example, powders such as colorants, pigments, dyes, surfactants, plasticizers, and additives may be appropriately added to the adhesive composition according to the application. Adhesives, surface lubricants, leveling agents, softeners, antioxidants, anti-aging agents, light stabilizers, ultraviolet absorbers, polymerization inhibitors, inorganic or organic fillers, metal powders, granules, foils, etc. In addition, it is also possible to use a redox system with a reducing agent added within a controllable range.

The aforementioned adhesive composition is used to form the adhesive layer, but when forming the adhesive layer, it is advisable to adjust the total amount of cross-linking agent added, and fully consider the effects of the cross-linking treatment temperature and the cross-linking treatment time.

The cross-linking treatment temperature or the cross-linking treatment time can be adjusted according to the cross-linking agent used. The cross-linking treatment temperature is preferably below 170°C.

In addition, the cross-linking treatment may be carried out at the temperature in the drying step of the adhesive layer, or it may be carried out by additionally providing a cross-linking treatment step after the drying step.

In addition, the crosslinking treatment time can be set in consideration of productivity and workability, and is usually about 0.2 to 20 minutes, preferably about 0.5 to 10 minutes. [Adhesive layer] The adhesive layer will be described.

The adhesive layer-attached polarizing film laminate system of the present invention is provided with an adhesive layer on at least one side of the polarizing film directly or via an optically transparent polarizing film protective film.

The method of forming the adhesive layer may include, for example, coating the aforementioned adhesive composition on a peel-off part, etc., and drying off the polymerization solvent to form an adhesive layer, and then transferring it to an optical film Method; or a method of coating the aforementioned adhesive composition on the optical film, and drying and removing the polymerization solvent, etc., to form an adhesive layer on the optical film, etc. In addition, for the application of the adhesive, one or more solvents other than the polymerization solvent can be newly added as appropriate.

It is better to use polysilicone release liner for the separated parts after peeling treatment. In the step of coating the aforementioned adhesive composition on the lining material and drying it to form an adhesive layer, the method of drying the adhesive may adopt a suitable method depending on the purpose. It is suitable to use a method of overheating and drying the above-mentioned coated film. The heating and drying temperature should be 40℃~200℃, more preferably 50℃~180℃, especially 70℃~170℃. By setting the heating temperature to the above range, an adhesive layer with excellent adhesive properties can be obtained.

Suitable drying time can be adopted. The drying time is preferably 5 seconds to 20 minutes, more preferably 5 seconds to 10 minutes, and particularly preferably 10 seconds to 5 minutes.

In addition, an anchor layer can be formed on the surface of the polarizing film, or an adhesive layer can be formed after various easy bonding treatments such as corona treatment and plasma treatment are performed. It is also possible to perform easy bonding treatment on the surface of the adhesive layer.

Regarding the anchor layer or the adhesive layer formed when the adhesive layer is provided on the surface of the polarizing film, it is also preferable to set it as an acid-free system when it is used.

The specific method of forming the anchor layer may include the following methods: a solution containing a urethane-based polymer (manufactured by Nagase ChemteX Co.: Denatron B510-C, etc.) with water/isopropanol (volume ratio 65:35) The mixed solution was adjusted to have a solid content of 0.2% by weight, and the adjusted solution was coated on a polarizing plate using wire rod #5, and dried at 50° C. for 30 seconds to form an anchor coating layer with a thickness of 25 nm.

Various methods can be used to form the adhesive layer. Specifically, for example, roll coating, touch roll coating, gravure coating, reverse coating, roll brushing, spray cloth, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, etc. Methods such as type coating, lip coating, and extrusion coating using a die coater.

The thickness of the adhesive layer is not particularly limited, and is, for example, about 1 to 500 μm. And it should be 1~250μm, more preferably 1~100μm, more preferably 1~35μm. By reducing the thickness of the adhesive layer, the overall amount of acid in the adhesive relative to the polarizing film can be reduced, and the impact on the polyalkenization of the polarizing film laminate with the adhesive layer can be reduced. Also, generally speaking, when the thickness of the adhesive layer becomes thinner, the adhesive force will gradually decrease, and the shrinkage stress of the polarizing plate caused by the shrinkage of the polarizing film under high temperature and humidity, resulting in embossing or peeling and other adhesion durability Therefore, it is not suitable to reduce the thickness of the adhesive layer. However, by making the polarizing film thinner, the shrinkage stress of the polarizing plate can be reduced. As a result, even if the thickness of the adhesive layer is reduced, the adhesion durability can be maintained or improved.

When the aforementioned adhesive layer is exposed, the peeled-off sheet (separator) can be used to protect the adhesive layer until it is used in practice.

Examples of constituent materials of the separator include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films; porous materials such as paper, cloth, and non-woven fabrics; meshes and foamed sheets Appropriate sheets such as, metal foil, and laminates thereof, etc., but from the viewpoint of excellent surface smoothness, plastic films can be suitably used.

The plastic film is not particularly limited as long as it can protect the aforementioned adhesive layer. Examples include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, and polyvinyl chloride film. , Vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene-ethyl acetate copolymer film, etc.

The thickness of the aforementioned separator is usually 5 to 200 μm, preferably about 5 to 100 μm. The aforementioned separation parts can also be subjected to mold release and antifouling treatment, coating type, kneading type, etc., using polysiloxane-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based mold release agents, silicon powder, etc. , Evaporation type and other antistatic treatment. In particular, by appropriately performing peeling treatments such as silicone treatment, long-chain alkyl treatment, and fluorine treatment on the surface of the separator, the peelability of the separator from the adhesive layer can be further improved.

In addition, the peel-off treated sheet used in the production of the above-mentioned adhesive layer-attached polarizing film laminate can be directly used as a separator for the adhesive layer-attached polarizing film laminate. Simplify the aspect.

2. Polarizing film laminate The polarizing film laminate 12 includes at least a polarizing film 120 and a polarizing film protective film 121 bonded to at least one surface of the polarizing film 120, such as the viewing side. It is also possible to join the polarizing film on both sides of the polarizing film 120, that is, the viewing side and the side opposite to the viewing side of the polarizing film 120, through an appropriate adhesive (not shown in the figure), respectively. Protective films 121, 122. Although not specifically shown in the figure, other optical films may be provided between the polarizing film 120 and the polarizing film protective films 121 and 122.

In order to comprehensively solve the problems caused by high temperature or high humidity environments, the present invention particularly focuses on the iodine concentration of the polarizing film 120 (wt. %) and the moisture content of the polarizing film laminate 12 (g/m ² ). These values can be adjusted, for example, when manufacturing a polarizing film or when manufacturing a polarizing film laminate.

2-1. Polarizing film The polarizing film 120 is composed of a polyvinyl alcohol (PVA) resin film containing iodine. PVA film materials suitable for polarizing films, PVA or its derivatives can be used. The derivatives of PVA can include polyvinyl formal, polyvinyl acetal, etc. Others can include olefins such as ethylene and propylene, acrylic acid, methacrylic acid, crotonic acid and other unsaturated carboxylic acids and their alkyl esters, and amide acrylates. Waiting for reformers. Generally, PVA with a degree of polymerization of about 1,000 to 10,000 and a degree of saponification of about 80 to 100 mole% is used. PVA-based films made from these materials tend to contain moisture.

The PVA-based film may also contain additives such as plasticizers. Examples of the plasticizer include polyhydric alcohols and condensates thereof, and examples thereof include glycerin, diglycerin, triglycerin, ethylene glycol, propylene glycol, and polyethylene glycol. Although there is no particular limitation on the amount of plasticizer used, it should preferably account for 20% by weight or less in the PVA-based film.

2-1-1. Manufacture of polarizing film When manufacturing a polarizing film with a film thickness of 6 μm or more, for example, a dyeing process of dyeing the above-mentioned PVA-based film with iodine and a stretching process of extending the PVA-based film in at least one direction may be performed. Generally, the above-mentioned PVA-based film is subjected to a series of treatments including swelling, dyeing, cross-linking, stretching, water washing and drying treatments.

The swelling treatment can be performed, for example, by immersing the PVA-based film in a swelling bath (water bath). By this treatment, the dirt and anti-blocking agent on the surface of the PVA-based film can be cleaned, and the PVA-based film can be swollen, thereby preventing unevenness such as uneven dyeing. Glycerin, potassium iodide, etc. can also be appropriately added to the swelling bath. The temperature of the swelling bath is, for example, about 20 to 60°C, and the immersion time for immersion in the swelling bath is, for example, about 0.1 to 10 minutes.

The dyeing treatment can be performed by immersing a PVA-based film in an iodine solution, for example. The iodine solution is usually an aqueous solution of iodine, and contains iodine and potassium iodide as a dissolution aid. The iodine concentration is, for example, about 0.01 to 1% by weight, and preferably 0.02 to 0.5% by weight. The potassium iodide concentration is, for example, about 0.01 to 10% by weight, and preferably 0.02 to 8% by weight.

In the dyeing process, the temperature of the iodine solution is, for example, about 20-50°C, and preferably 25-40°C. The immersion time is, for example, about 10 to 300 seconds, and preferably in the range of 20 to 240 seconds. During the iodine dyeing process, the concentration of the iodine solution, the immersion temperature of the PVA-based film in the iodine solution, and the immersion time are adjusted so that the iodine content and potassium content in the PVA-based film are within the aforementioned ranges.

The cross-linking treatment can be performed, for example, by immersing the iodine-dyed PVA-based film in a treatment bath containing a cross-linking agent. Any appropriate cross-linking agent can be used as the cross-linking agent. Specific examples of the crosslinking agent include boron compounds such as boric acid and borax, glyoxal, and glutaraldehyde. These can be used alone or in combination. The solvent of the solution used in the crosslinking bath is generally water, but an organic solvent compatible with water may be added in an appropriate amount. The crosslinking agent can be used in a ratio of, for example, 1 to 10 parts by weight with respect to 100 parts by weight of the solvent. The solution of the cross-linking bath preferably contains iodide and other auxiliary agents. The concentration of the auxiliary agent is preferably 0.05 to 15% by weight, and more preferably 0.5 to 8% by weight. The temperature of the crosslinking bath is, for example, about 20 to 70°C, and preferably 40 to 60°C. The immersion time in the crosslinking bath is, for example, about 1 second to 15 minutes, and preferably 5 seconds to 10 minutes.

The stretching process is a process of stretching the PVA-based film in at least one direction. Generally, PVA-based films are uniaxially stretched in the conveying direction (long-side direction). The extension method is not particularly limited, and any one of the wet extension method and the dry extension method can be used. When the wet stretching method is used, the PVA-based film is stretched at a predetermined rate in the treatment bath. The solution of the extension bath can be suitably used as a solution obtained by adding various compounds required for treatment to a solvent such as water or an organic solvent (for example, ethanol). Examples of the dry stretching method include an inter-roll stretching method, a heated roll stretching method, and a compression stretching method. In the manufacture of the polarizing film, the stretching treatment can be carried out at any stage. Specifically, it can be performed simultaneously with swelling, dyeing, and crosslinking, or it can be performed at any timing before or after each of these treatments. Moreover, the extension can also be carried out in multiple stages. The cumulative stretching ratio of the PVA-based film is, for example, 5 times or more, and preferably about 5 to 7 times.

The PVA-based film (stretched film) subjected to the above-mentioned various treatments is subjected to water washing treatment and drying treatment according to a conventional method.

The water washing treatment can be performed, for example, by immersing the PVA-based film in a water bath. The water bath can be pure water or an aqueous solution of iodide (such as potassium iodide, sodium iodide, etc.). The concentration of the iodide aqueous solution is preferably 0.1 to 10% by weight. Additives such as zinc sulfate and zinc chloride can also be added to the iodide aqueous solution.

The washing temperature is, for example, 5 to 50°C, and preferably 10 to 45°C, more preferably 15 to 40°C. The immersion time is, for example, about 10 to 300 seconds, and preferably 20 to 240 seconds. The water washing treatment can be carried out only once, or it can be carried out multiple times as needed. When multiple washing treatments are performed, the type or concentration of additives contained in the water bath used for each treatment can be adjusted appropriately.

The drying treatment of the PVA-based film can be performed by any appropriate method (for example, natural drying, air drying, heat drying).

2-1-2. Manufacture of polarizing film A polarizing film with a film thickness of less than 6 μm can be manufactured by the manufacturing method disclosed in Japanese Patent No. 4751481, for example. The manufacturing method includes the following treatments: laminated body preparation treatment, which is to form a PVA-based resin layer on a thermoplastic substrate; stretching treatment, which is to integrally extend the PVA-based resin layer and the thermoplastic resin substrate; dyeing treatment, to make PVA The resin layer adsorbs dichroic substances. It is also possible to apply the insolubilization treatment, cross-linking treatment, drying treatment, cleaning treatment, etc. of the PVA-based resin layer according to the needs. The extension treatment can be performed before or after the dyeing treatment, and any extension method of air extension and extension in water such as boric acid aqueous solution can also be used. In addition, the extension can be a one-stage extension or a multi-stage extension with more than two stages.

An example of a method of manufacturing a polarizing film will be described with reference to FIG. 2. Here, a polarizing film is produced by integrally extending the PVA-based resin layer formed on the resin substrate and the aforementioned resin substrate.

[Layered body production processing (A)] First, prepare an amorphous ester-based thermoplastic resin substrate with a thickness of 200 μm with a glass transition temperature of 75°C. For example, 6 mol% of isophthalic acid is copolymerized to form a poly(ethylene terephthalate) copolymer (hereinafter Called "amorphous PET") 6. A 4 to 5 wt% aqueous PVA solution obtained by dissolving PVA powder with a degree of polymerization of 1,000 or more and a saponification degree of 99% or more in water. Next, in a laminate manufacturing device 20 equipped with a coating mechanism 21, a drying mechanism 22, and a surface modification treatment device 23, the PVA aqueous solution is coated on the amorphous PET substrate 6, and the temperature is 50-60°C It was dried, and a PVA layer 2 having a thickness of 7 μm with a glass transition temperature of 80° C. was formed on the PET substrate 6. In this way, a laminate 7 including a PVA layer having a thickness of 7 μm was produced. At this time, by corona treatment of the surface of the amorphous PET substrate 6 with the surface modification treatment device 23, the adhesion between the amorphous PET substrate 6 and the PVA layer 2 formed on it can be improved .

Next, the laminate 7 including the PVA layer was subjected to the following treatments including two-stage stretching treatment including aerial auxiliary stretching and boric acid water stretching, and finally a polarizing film with a thickness of 3 μm was produced.

[Air auxiliary extension processing (B)] In the air-assisted stretching process (B) in the first stage, the laminate 7 including the PVA layer 2 with a thickness of 7μm and the PET base material 6 are integrally extended to produce the "extended laminate" including the PVA layer 2 with a thickness of 5μm 8". Specifically, in the air-assisted stretching processing device 30 equipped with the stretching mechanism 31 in the oven 33, the laminate 7 including the PVA layer 2 with a thickness of 7 μm is placed in the oven 33 set to a stretching temperature environment of 130°C. On the mechanism 31, the free end is uniaxially stretched so that the stretch magnification becomes 1.8 times, and the stretched laminate 8 is produced. At this stage, the coiling device 32 installed in the oven 30 can be used to manufacture the coil 8'of the stretched laminate 8.

[Dyeing treatment (C)] Next, by the dyeing process (C), a colored laminate 9 is produced, and the colored laminate 9 is a PVA layer 2 having a thickness of 5 μm in which PVA molecules are oriented and adsorbs iodine as a dichroic substance. Specifically, in the dyeing device 40 provided with the dyeing bath 42 of the dyeing liquid 41, the rolled material 8'attached to it is discharged from the discharging device 43 collectively provided in the dyeing device 40 to obtain the stretched laminate. 8. Immerse it in a dyeing solution 41 containing iodine and potassium iodide at a liquid temperature of 30°C for an arbitrary period of time so that the monomer transmittance of the PVA layer that constitutes the final polarizing film becomes 40~44%, thereby forming a stretched laminate The oriented PVA layer 2 of the body 8 adsorbs the colored layered body 9 of iodine.

In this process, in order not to dissolve the PVA layer 2 contained in the stretched laminate 8 in the dyeing solution 41, water is used as a solvent, and the iodine concentration is set to 0.30 weight%. In addition, in the dyeing solution 41, the potassium iodide concentration for dissolving iodine in water was 2.1% by weight. The concentration ratio of iodine to potassium iodide is 1:7. In more detail, the stretched laminate 8 is immersed in a dyeing solution 41 with an iodine concentration of 0.30% by weight and a potassium iodide concentration of 2.1% by weight for 60 seconds, thereby generating a 5μm thick PVA layer 2 in which PVA molecules are oriented. Colored laminate 9.

[Extension Treatment in Boric Acid Water (D)] By the second stage of the boric acid water extension treatment, the colored laminate 9 including the iodine-oriented PVA layer 2 is further extended to produce an optical thin film laminate 60 including a 3 μm thick polarizing film and a PVA layer oriented with iodine . Specifically, in the boric acid water extension treatment device 50 provided with the boric acid bath 52 of the boric acid aqueous solution 51 and the extension mechanism 53, the colored layered body 9 continuously released from the dyeing device 40 is immersed in a set containing boric acid and potassium iodide. In the boric acid aqueous solution 51 in an extension temperature environment of 65°C, it is then placed on the extension mechanism 53 equipped in the boric acid water treatment device 50, and the free end is uniaxially extended to a stretching magnification of 3.3 times, thereby generating Optical film laminate 60 with a thickness of 3 μm PVA layer.

[Washing treatment (G)] Next, it is preferable to directly send the optical thin film laminate 60 containing the polarizing film to the cleaning process (G). The purpose of the washing treatment (G) is to use the washing liquid 81 of the washing device 80 to wash away unnecessary residues adhering to the surface of the polarizing film. However, the cleaning process (G) may be omitted, and the optical thin film laminate 60 containing the polarizing film that has been taken out may be directly sent to the drying process (H).

[Drying treatment (H)] The cleaned optical film laminate 60 is sent to the drying process (H) and dried there. Next, the dried optical film laminate 60 is wound in the form of a continuous belt-shaped optical film laminate 60 with a winding device 91 integrated in the drying device 90 to produce an optical film laminate 60 including a polarizing film Of rolls. The drying treatment (H) can adopt any appropriate method, such as natural drying, air blowing drying, and heating drying. For example, it can be dried in a drying device 90 of an oven with warm air at 60°C for 240 seconds.

2-1-3. Other The polarizing film preferably contains zinc. Since the polarizing film contains zinc, there is a tendency to suppress the decrease in transmittance and hue deterioration of the polarized film laminate after the heating test. When the polarizing film contains zinc, the zinc content in the polarizing film is preferably 0.002 to 2% by weight, and preferably 0.01 to 1% by weight.

The polarizing film should also contain sulfate ions. Since the polarizing film contains sulfate ions, there is a tendency to suppress the decrease in the transmittance of the polarizing film laminate after the heating test. When the polarizing film contains sulfate ions, the sulfate ion content in the polarizing film is preferably 0.02 to 0.45% by weight, preferably 0.05 to 0.35% by weight, and more preferably 0.1 to 0.25% by weight. In addition, the sulfate ion content in the polarizing film is calculated from the sulfur atom content.

If zinc is to be contained in the polarizing film, it is advisable to impregnate zinc in the manufacturing step of the polarizing film. In addition, in order to include sulfate ions in the polarizing film, it is preferable to perform sulfate ion treatment in the manufacturing step of the polarizing film.

The zinc impregnation treatment can be performed, for example, by immersing the PVA-based film in a zinc salt solution. The zinc salt is preferably an inorganic salt compound in an aqueous solution such as zinc chloride, zinc iodide, zinc halide, zinc sulfate, and zinc acetate. In addition, various zinc complex compounds can also be used in the zinc impregnation treatment. In addition, it is preferable to use an aqueous solution containing potassium ions and iodide ions using potassium iodide or the like for the zinc salt solution because it is easy to impregnate zinc ions. The potassium iodide concentration in the zinc salt solution is set to about 0.5-10% by weight, and preferably 1-8% by weight.

The sulfate ion treatment is performed, for example, by immersing the PVA-based film in an aqueous solution containing a metal sulfate salt. It is preferable that the metal sulfate is easily separated into sulfate ions and metal ions in the treatment liquid, and the metal sulfate is easily introduced into the PVA-based film in the form of ions. For example, the types of metals that form the metal sulfate salt include alkali metals such as sodium and potassium; alkaline earth metals such as magnesium and calcium; and transition metals such as cobalt, nickel, zinc, chromium, aluminum, copper, manganese, and iron.

In the production of the polarizing film, the above-mentioned zinc impregnation treatment and sulfate ion treatment can be performed at any stage. That is, the zinc impregnation treatment and the sulfate ion treatment may be performed before the dyeing treatment or may be performed after the dyeing treatment. Zinc impregnation treatment and sulfate ion treatment can also be carried out at the same time. Preferably, zinc sulfate is used for the zinc salt and the metal sulfate salt, and the PVA-based film is immersed in a treatment bath containing zinc sulfate, thereby simultaneously performing the zinc impregnation treatment and the sulfate ion treatment. In addition, the zinc salt or the metal sulfate salt may be first coexisted in the dyeing solution, and then the zinc impregnation treatment and/or the sulfate ion treatment may be performed simultaneously with the dyeing treatment. Zinc impregnation treatment and sulfate ion treatment can also be carried out at the same time as the extension.

2-2. Polarizing film protective film The material constituting the polarizing film protective films 121 and 122 may include, for example, a thermoplastic resin having excellent transparency, mechanical strength, and thermal stability. Specific examples of thermoplastic resins include cellulose resins such as cellulose triacetate, polyester resins, polyether-based resins, poly-based resins, polycarbonate-based resins, polyamide-based resins, and polyimides. Resins, polyolefin resins, (meth)acrylic resins, cyclic polyolefin resins (norbornene resins), polyarylate resins, polystyrene resins, PVA resins, and mixtures of these . The polarizing film protective film may also have the function of a retardation film.

The thickness of the polarizing film protective film can be adjusted appropriately in order to adjust the moisture content of the polarizing film laminate. From the viewpoints of workability and thin layer properties such as strength and handling properties, it is preferably about 1 to 500 μm, preferably 2 to 300 μm, and more preferably 5 to 200 μm. The polarizing film protective film may contain one or more arbitrary additives. Examples of additives include ultraviolet absorbers, antioxidants, slip agents, plasticizers, mold release agents, anti-colorants, flame retardants, nucleating agents, antistatic agents, pigments, colorants, and the like.

2-3. Other optical films The polarizing film and the polarizing film protective film can be directly bonded, but they can also be laminated with other optical films. Other optical films are not particularly limited, and for example, retardation films, viewing angle compensation films, etc. can be used. The retardation film as another optical film may be one having the function as a protective film.

As described above, the polarizing film protective film may also have the function of a retardation film, and at this time, it may be omitted as a retardation film of other optical films. On the other hand, even when the polarizing film protective film has the functions of a retardation film, the retardation film can still be provided as other optical films. In this case, two or more retardation films are substantially included.

2-4. Adhesive When bonding the polarizing film 120 to the polarizing film protective films 121 and 122, or bonding other optical films such as retardation films to these, for example, a radical polymerization hardening type adhesive, a cation polymerization hardening type adhesive, and an aqueous adhesive can be used. .

(Free radical polymerization hardening adhesive) The aforementioned radical polymerization curable adhesive includes a radical polymerizable compound as a curable compound. The radically polymerizable compound may be a compound that is cured by active energy rays, or a compound that is cured by heat. Examples of active energy rays include electron beams, ultraviolet rays, and visible rays.

Examples of the aforementioned radically polymerizable compound include compounds having a radically polymerizable functional group having a carbon-carbon double bond such as a (meth)acryloyl group and a vinyl group. As the radical polymerizable compound, a polyfunctional radical polymerizable compound is preferably used. A radically polymerizable compound may be used individually by 1 type, and may be used in combination of 2 or more types. Moreover, a polyfunctional radical polymerizable compound and a monofunctional radical polymerizable compound can also be used together.

As the aforementioned polymerizable compound, it is preferable to use a compound with a high logP value (octanol/water partition coefficient), and it is also preferable to select a compound with a high logP value for the radical polymerizable compound. Here, the logP value represents an index of the lipophilicity of a substance, and means the logarithmic value of the octanol/water partition coefficient. A high logP value represents lipophilicity, which means low water absorption. The logP value can be measured (the flask permeation method described in JIS-Z-7260), or it can be calculated by calculating the structure of each compound based on the constituent components (curable components, etc.) of the hardening adhesive (made by CambridgeSoft) ChemDraw Ultra).

The logP value of the radically polymerizable compound is preferably 2 or more, preferably 3 or more, and more preferably 4 or more. As long as it is within the above range, the polarizer can be prevented from being degraded by moisture, and a polarizing film with excellent durability under high temperature and high humidity can be obtained.

烷二醇二(甲基)丙烯酸酯、三羥甲丙烷三(甲基)丙烯酸酯、新戊四醇三(甲基)丙烯酸酯、新戊四醇四(甲基)丙烯酸酯、二新戊四醇五(甲基)丙烯酸酯、二新戊四醇六(甲基)丙烯酸酯、EO改質二丙三醇四(甲基)丙烯酸酯等(甲基)丙烯酸酯與多元醇之酯化物；9,9-雙[4-(2-(甲基)丙烯醯氧基乙氧基)苯基]茀；(甲基)丙烯酸環氧酯；(甲基)丙烯酸胺甲酸酯；聚酯(甲基)丙烯酸酯等。Examples of the aforementioned polyfunctional radical polymerizable compound include: tripropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1 , 9-nonanediol di(meth)acrylate, 1,10-decanediol diacrylate, 2-ethyl-2-butylpropanediol di(meth)acrylate, bisphenol A bis(methyl) )Acrylate, bisphenol A ethylene oxide adduct di(meth)acrylate, bisphenol A propylene oxide adduct di(meth)acrylate, bisphenol A diglycidyl ether two ( Meth) acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, two

Alkyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, neopentyl erythritol tri(meth)acrylate, neopentyl erythritol tetra(meth)acrylate, dineopentyl Tetraol penta(meth)acrylate, dineopentaerythritol hexa(meth)acrylate, EO modified diglycerol tetra(meth)acrylate and other (meth)acrylates and polyol esters ; 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]茀; (meth)acrylate epoxy; (meth)acrylate urethane; polyester (Meth)acrylate and the like.

Among the aforementioned polyfunctional radical polymerizable compounds, a polyfunctional radical polymerizable compound having a high logP value is preferable. The compound includes, for example, alicyclic (meth)acrylates such as tricyclodecane dimethanol di(meth)acrylate (logP=3.05), isobornyl (meth)acrylate (logP=3.27); 1, Long-chain aliphatic (meth)acrylates such as 9-nonanediol di(meth)acrylate (logP=3.68) and 1,10-decanediol diacrylate (logP=4.10); hydroxytrimethylacetic acid Multi-branched (meth)acrylates such as neopentyl glycol (meth)acrylic acid adducts (logP=3.35), 2-ethyl-2-butylpropanediol di(meth)acrylate (logP=3.92), etc. ; Bisphenol A di(meth)acrylate (logP=5.46), bisphenol A ethylene oxide 4 mol adduct di(meth)acrylate (logP=5.15), bisphenol A propylene oxide 2 Mole adduct di(meth)acrylate (logP=6.10), bisphenol A propylene oxide 4 Mole adduct di(meth)acrylate (logP=6.43), 9,9-bis(4 -(2-(Meth)acryloyloxyethoxy)phenyl)Phenyl (logP=7.48), p-phenylphenol (meth)acrylate (logP=3.98) and other aromatic ring-containing (methyl) Acrylic etc.

When a polyfunctional radical polymerizable compound and a monofunctional radical polymerizable compound are used together, the content ratio of the polyfunctional radical polymerizable compound relative to the total amount of the radical polymerizable compound is preferably 20 to 97% by weight, more preferably 50 to 95 Weight %, 75 to 92 weight% is more preferable, and 80 to 92 weight% is particularly preferable. As long as it is within the above range, a polarizing film with excellent durability under high temperature and high humidity can be obtained.

Examples of the monofunctional radical polymerizable compound include (meth)acrylamide derivatives having a (meth)acrylamide group. As long as the (meth)acrylamide derivative is used, an adhesive layer with good adhesion can be formed with high productivity. Specific examples of (meth)acrylamide derivatives include N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl ( (Meth)acrylamide, N-isopropyl(meth)acrylamide, N-butyl(meth)acrylamide, N-hexyl(meth)acrylamide, etc. containing N-alkyl ( (Meth)acrylamide derivatives; N-hydroxymethyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-hydroxymethyl-N-propane (meth)acrylamide N-hydroxyalkyl-containing (meth)acrylamide derivatives such as amines; aminomethyl(meth)acrylamide, aminoethyl(meth)acrylamide, etc., containing N-aminoalkyl(form) Base) acrylamide derivatives; N-alkoxy-containing (meth)acrylamide derivatives such as N-methoxymethacrylamide, N-ethoxymethacrylamide, etc.; mercaptomethyl(formaldehyde) (Meth)acrylamide, mercaptoethyl (meth)acrylamide and other N-mercaptoalkyl-containing (meth)acrylamide derivatives. In addition, the nitrogen atom of the (meth)acrylamide group forms a heterocyclic ring-containing (meth)acrylamide derivative. For example, N-acryloyl mopholin and N-acryloyl piperidine can be used. , N-methacryloylpiperidine and N-acryloylpyrrolidine, etc. Among them, N-hydroxyalkyl-containing (meth)acrylamide derivatives are preferred, and N-hydroxyethyl (meth)acrylamide is more preferred.

、乙烯基吡

、乙烯基吡咯、乙烯基咪唑、乙烯基

唑、乙烯基嗎福林等具有含氮雜環之乙烯基系單體等。In addition, the aforementioned monofunctional radical polymerizable compound can also use (meth)acrylic acid derivatives having a (meth)acryloyloxy group; (meth)acrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, and itaconic acid. , Maleic acid, fumaric acid, crotonic acid, isocrotonic acid and other carboxyl-containing monomers; N-vinylpyrrolidone, N-vinyl-ε-caprolactone, methylvinylpyrrolidone and other internal amines Series vinyl monomer; vinyl pyridine, vinyl piperidone, vinyl pyrimidine, vinyl piper

Vinylpyridine

, Vinyl pyrrole, vinyl imidazole, vinyl

Vinyl monomers with nitrogen-containing heterocycles such as azole, vinylmorphine, etc.

When a polyfunctional radical polymerizable compound and a monofunctional radical polymerizable compound are used in combination, the content ratio of the monofunctional radical polymerizable compound relative to the total amount of the radical polymerizable compound is preferably 3 to 80% by weight, more preferably 5 to 50 % By weight, more preferably 8-25% by weight, particularly preferably 8-20% by weight. As long as it is within the above range, a polarizing film with excellent durability under high temperature and high humidity can be obtained.

The aforementioned radical polymerization hardening adhesive may further contain other additives. When the radical polymerization curable adhesive includes a curable compound that is cured by active energy rays, the adhesive may further include, for example, a photopolymerization initiator, a photoacid generator, a silane coupling agent, and the like. In addition, when the radical polymerization curable adhesive includes a curable compound that is cured by heat, the adhesive may further include a thermal polymerization initiator, a silane coupling agent, and the like. In addition, examples of other additives include polymerization inhibitors, polymerization initiation aids, leveling agents, wettability modifiers, surfactants, plasticizers, ultraviolet absorbers, inorganic fillers, pigments, dyes, and the like.

(Cation polymerization hardening adhesive) The aforementioned cationic polymerization curable adhesive includes a cationic polymerizable compound as a curable compound. Examples of the cationically polymerizable compound include compounds having an epoxy group and/or oxetanyl group. The compound having an epoxy group is preferably used for a compound having at least two epoxy groups in the molecule. Examples of compounds having epoxy groups include compounds having at least two epoxy groups and at least one aromatic ring (aromatic epoxy compounds), and at least two epoxy groups in the molecule, and at least one of them is formed in A compound between two adjacent carbon atoms constituting an alicyclic ring (alicyclic epoxy compound), etc.

The aforementioned cationic polymerization hardening type adhesive preferably contains a photocationic polymerization initiator. The photocationic polymerization initiator is irradiated with active energy rays such as visible rays, ultraviolet rays, X-rays, electron beams, etc., to generate cationic species or Lewis acid, and initiate the polymerization reaction of epoxy groups or oxetanyl groups. In addition, the cationic polymerization curable adhesive may further contain the aforementioned additives.

(Aqueous adhesive) As the aforementioned aqueous adhesive, for example, an aqueous solution of an aqueous adhesive such as an isocyanate-based adhesive, PVA-based adhesive, gelatin-based adhesive, vinyl-based latex-based, water-based polyester, etc. (for example, a solid content concentration of 0.5 to 60% by weight) can be suitably used.

The coating of the adhesive may be performed on any one of the polarizing film 120, the polarizing film protective films 121 and 122, and other optical films, or may be performed on any two of them. Generally speaking, a method of immersing the polarizing film in the adhesive aqueous solution and laminating it with the polarizing film protective films 121 and 122 using a roll laminator or the like is suitable. The thickness of the subsequent layer is not particularly limited, and for example, it is about 30 nm to 1000 nm in terms of the thickness after drying.

After the polarizing film, the polarizing film protective film and other optical films are laminated through the adhesive, the laminated system is subjected to a drying process. In addition to the purpose of drying and curing the adhesive, the drying step of the laminate is performed for the purpose of reducing the moisture content and improving the initial optical properties of the polarizing film laminate. The drying method is generally heating and drying. The drying conditions are preferably in the range of 50 to 95°C, preferably in the range of 60 to 85°C.

The drying conditions of the laminate are not particularly limited. In consideration of processing efficiency or practicality, the drying temperature is preferably 50°C or higher, and from the viewpoint of making the optical properties of the polarizing film laminate uniform, it is preferably 95°C or lower. The drying temperature can also be implemented by raising the temperature step by step within the above-mentioned temperature range.

The drying of the laminate can be carried out continuously with the joining process of the polarizing film, the polarizing film protective film and other optical films. In addition, a laminate of a polarizing film, a polarizing film protective film, and other optical films may be temporarily wound into a roll state, and then drying may be performed as another process.

Generally speaking, to reduce the moisture content of the polarizing film laminate, high temperature and long-term drying conditions are necessary. Drying at high temperature and long time is ideal from the viewpoint of reducing the moisture content of the polarizing film laminate, but on the other hand, the optical properties of the polarizing film laminate may decrease. By using a polarizing film protective film with small saturated water absorption or a polarizing film protective film with high moisture permeability, the moisture content of the polarizing film laminate can be adjusted to the aforementioned desired range without using severe drying conditions.

2-5. Adhesive The adhesive described in the above "1-3. Transparent Adhesive" can be used in the same way.

3. Reliability Evaluation Project Evaluate the various phenomena of polarized film laminates, namely polyolefinization, fading, red change on heating, adhesion durability and reworkability. Although the mechanism of each phenomenon is not yet clear, our guess is as follows.

推測是存在於偏光膜中之PVA-多碘錯合物因加熱而被破壞所產生之I₂ 與PVA中之OH基會形成電荷轉移錯合物(HO・・・I₂ )，然後經由OI基而多烯化。吾等認為當黏著劑層中包含大量酸成分時，由酸成分產生之質子會作為PVA之脫水反應的觸媒發揮作用，故會更促進多烯化。<Polyolefinization> In a high-temperature and high-humidity environment, the monomer transmittance of the polarizing film laminate will decrease. We speculate that the polyolefination of PVA is the cause of this decrease. Polyene refers to -(CH=CH) _n -, which is formed in the polarizing film under heating. Polyene will significantly reduce the transmittance of the polarizing film. Moreover, under high temperature and high humidity environment, PVA-polyiodide complexes will be destroyed and I ^- and I ₂ are easily formed. We speculate that the polyolefination of PVA is shown in the following chemical formula 1, _{which occurs due to iodine (I 2} ) generated in a high temperature and high humidity environment and heating to promote the dehydration reaction. (Chemical formula 1)

It is presumed that the PVA-polyiodide complex in the polarizing film is destroyed by heating. The I ₂ produced by the heating and the OH group in the PVA will form a charge transfer complex (HO・・・I ₂ ), and then pass through OI Base and polyethylenization. We believe that when the adhesive layer contains a large amount of acid components, the protons generated by the acid components will act as a catalyst for the dehydration reaction of PVA, which will further promote polyolefinization.

<Fading> In the iodine-dyed and stretched PVA-based film (polarizing film), the iodine system forms a complex with the oriented PVA in the form of _{I 3} ^- and I ₅ ^{-polyiodide ions (PVA polyiodide complex}物). At this time, the PVA system uses a cross-linking agent such as boric acid to form cross-linking points, thereby maintaining the orientation. However, if the polarizing film is placed under high temperature and high humidity, the cross-linking of boric acid will undergo hydrolysis, which will reduce the orientation of PVA and cause the collapse of the PVA polyiodide complex. Therefore, the PVA polyiodide complex will cause a decrease in visible light absorption, and the transmittance of the long wavelength side of about 700 nm and the short wavelength side of about 410 nm will increase. As mentioned above, the polarizing film placed under high temperature and high humidity will fade under black display.

<Heating red change> In the iodine-dyed and stretched PVA-based thin film (polarizing film), the iodine forms a complex with PVA in the form of _{I 3} ^- and I ₅ ^{-polyiodide ions (PVA polyiodide complex} ). I ₃ ^- has a broad absorption peak near 470 nm, and I ₅ ^- has a broad absorption peak near 600 nm. That is, PVA-I ₃ ^- complexes responsible absorb short wavelength side (blue side) of, the PVA-I ₅ ^- complexes responsible for absorbing the long wavelength side (red side) of. However, the PVA-I ₅ ^- complex is not resistant to heating. If the polarizing film is placed at a high temperature, the _{formation of the complex of PVA and I 5} ^- will collapse, and the I ₅ ^- will decompose. Accordingly, the polarizing film was placed under the high temperature, it is responsible for the absorption of the long wavelength side of the PVA-I ₅ ^- complexes will decrease, i.e., a transmittance of about 700nm to the long wavelength side will rise, while the red color will polarizing . Example

4. Examples and Comparative Examples The following describes the examples and comparative examples together, and the present invention should not be limited to those described in these examples. In the examples and comparative examples, "the film thickness of the polarizing film (μm)", and/or "the iodine concentration of the polarizing film (wt.%)", and/or the "water content of the polarizing film laminate (g/ m ² )" samples of different polarizing film laminates.

＜Film thickness of polarizing film＞ The film thickness (μm) of the polarizing film was measured using a spectrophotometer MCPD-1000 (manufactured by Otsuka Electronics Co., Ltd.). The thickness of the polarizing film protective film is also measured using it. The polarizing film contained in the sample can be taken out by immersing the sample in a solvent to dissolve the polarizing film protective film. For the solvent, for example, dichloromethane is used when the polarizing film protective film is triacetyl cellulose resin, cyclohexane is used when the polarizing film protective film is cycloolefin resin, and methyl ethyl is used when the polarizing film protective film is acrylic resin.基ketone. In addition, when the resin of the protective film of the polarizing film provided on one side of the polarizing film is different from the resin of the protective film of the polarizing film provided on the other side, the above-mentioned solvents are used to sequentially dissolve the resins.

＜Iodine concentration of polarizing film＞ The iodine concentration (wt.%) of the polarizing film can be changed when the polarizing film is manufactured, for example, by adjusting the concentration or immersion time of the iodine aqueous solution used to immerse the PVA-based film or the PVA layer. The iodine concentration of the polarizing film was measured by the following method. In addition, the polarizing film contained in the sample can be taken out by immersing the sample in a solvent to dissolve the protective film of the polarizing film in the same manner as when measuring the film thickness of the polarizing film. (X-ray fluorescence measurement) When measuring the iodine concentration of the polarizing film, firstly, the iodine concentration is quantified by the calibration curve method of X-ray fluorescence analysis. An X-ray fluorescence analyzer ZSX-PRIMUS IV (manufactured by Rigaku) was used as the device. The value directly obtained by the X-ray fluorescence analysis device is not the concentration of each element, but the X-ray fluorescence intensity (kcps) of the inherent wavelength of each element. Therefore, in order to obtain the concentration of iodine contained in the polarizing film, a calibration curve must be used to convert the X-ray fluorescence intensity into a concentration. The iodine concentration of the polarizing film in this specification and the like refers to the iodine concentration (wt%) based on the weight of the polarizing film.

(Create calibration curve) Make the calibration curve according to the following procedure. 1. Dissolve a known amount of potassium iodide into the PVA aqueous solution to make 7 kinds of PVA aqueous solutions containing iodine with a known concentration. The PVA aqueous solution was applied to polyethylene terephthalate, dried, and then peeled off to produce samples 1-7 of PVA film containing iodine of known concentration. In addition, the iodine concentration (wt%) of the PVA film is calculated using the following Mathematical Formula 1. [Math 1] 　Iodine concentration (wt%) = {Amount of potassium iodide (g)/(Amount of potassium iodide (g) + Amount of PVA (g))}×(127/166) (Molecular weight of iodine: 127　 Molecular weight of potassium: 39)

2. For the produced PVA film, the X-ray fluorescence analyzer ZSX-PRIMUS IV (manufactured by Rigaku) was used to measure the X-ray fluorescence intensity (kcps) corresponding to iodine. In addition, the X-ray fluorescence intensity (kcps) is the peak value of the X-ray fluorescence spectrum. In addition, the thickness of the produced PVA film was measured using a spectroscopic film thickness meter MCPD-1000 (manufactured by Otsuka Electronics Co., Ltd.).

3. Divide the X-ray fluorescence intensity by the thickness of the PVA film (μm) to calculate the X-ray fluorescence intensity per unit thickness of the film (kcps/μm). Table 1 shows the iodine concentration of each sample and the X-ray fluorescence intensity per unit thickness.

[Table 1]

4. Based on the results shown in Table 1, the X-ray fluorescence intensity per unit thickness of the PVA film (kcps/μm) is taken as the horizontal axis, and the iodine concentration in the PVA film (wt%) is taken as the vertical axis. Calibration curve. Figure 3 shows the completed calibration curve. The mathematical formula for obtaining the iodine concentration from the X-ray fluorescence intensity per unit thickness of the PVA film obtained from the calibration curve is shown in mathematical formula 2. In addition, R ^{2 in} Figure 3 is the correlation coefficient. [Math 2] (Iodine concentration) (wt%) = 14.474 × (X-ray fluorescence intensity per unit thickness of PVA film) (kcps/μm)

(Calculate the iodine concentration) The X-ray fluorescence intensity obtained by measuring the sample is divided by the thickness to obtain the X-ray fluorescence intensity per unit thickness (kcps/μm). The X-ray fluorescence intensity per unit thickness of each sample is substituted into Equation 2 to obtain the iodine concentration.

<Moisture content of the polarizing film laminate> The moisture content (g/m ² ) of the polarizing film laminate can be determined mainly by adjusting the film thickness of the polarizing film, and the material and thickness of the polarizing film protective film bonded to the polarizing film. Moreover, it can also be adjusted by the crosslinking process (boric acid content etc.) etc. at the time of manufacturing a polarizing film. The moisture content of the polarizing film laminate is measured according to the following method. First, the polarizing film laminates obtained in the examples and comparative examples were cut into a square of 0.1 m×0.1 m. Put the cut sample into a constant temperature and humidity machine, and place it in an environment with a temperature of 23°C and a relative humidity of 55% for 48 hours. After that, the sample was taken out in a clean room set to the same environment as the constant temperature and humidity machine, that is, a temperature of 23°C and a relative humidity of 55%, and the weight was measured within 5 minutes after taking it out. The weight of the sample at this time is taken as the initial weight W1 (g). In addition, after taking it out, as long as within about 15 minutes, even if the temperature in the clean room fluctuates by about 2°C to 3°C, or the relative humidity in the clean room fluctuates by about ±10%, the initial weight will not be substantially affected. . Next, put the taken-out sample into a desiccator and dry it at 120°C for 2 hours. After that, the dried sample was taken out in the above-mentioned clean room set to a temperature of 23°C and a relative humidity of about 55%, and the weight was measured within 10 minutes after taking it out. The weight of the sample at this time was taken as the weight after drying W2 (g). Different from the above-mentioned setting within 5 minutes and within 10 minutes, it is because the cooling time is taken into consideration. In addition, similar to the above, as long as it is within about 15 minutes after taking it out, the weight after drying will not be substantially affected. From the initial weight W1 and the dried weight W2 of the sample obtained above, the equilibrium moisture content M (g/m ² ) of the polarizing film laminate was calculated using the following formula. (Formula) M=(W1―W2)/(0.1×0.1) The "moisture content of the polarizing film laminate" mentioned in the present invention means the equilibrium moisture content calculated by the above method.

(Making adhesive layer A) First, a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler was charged with 80.9 parts of butyl acrylate, 18 parts of benzyl acrylate, 1 part of acrylic acid, and 0.1 part of 4-hydroxybutyl acrylate to obtain Monomer mixture. And with respect to 100 parts of the monomer mixture (solid content), 0.1 part of 2,2'-azobisisobutyronitrile as a polymerization initiator was fed together with 100 parts of ethyl acetate. While slowly stirring the mixture, nitrogen was introduced into the flask for nitrogen substitution. By maintaining the liquid temperature in the flask at around 55°C for 8 hours, the polymerization reaction was carried out to prepare an acrylic polymer solution with a weight average molecular weight (Mw) of 1.85 million and Mw/Mn=3.8.

Next, with respect to 100 parts of the solid content of the acrylic polymer solution, 0.45 parts of isocyanate crosslinking agent (Coronate L manufactured by Tosoh, trimethylolpropane toluene diisocyanate) and benzyl peroxide were further blended. 0.1 part of 醯 (NYPER BMT manufactured by Nippon Oil & Fat Co., Ltd.) and 0.2 part of γ-glycidoxypropyl methoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-403) to prepare an acrylic adhesive composition Solution.

Next, the obtained solution was applied to one side of a separator (MRF38 manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.). The separation part is a polyethylene terephthalate film that has been treated with a silicone-based release agent. The obtained coating film was dried at 155° C. for 1 minute, thereby forming an adhesive layer A on the surface of the separator. The thickness of the adhesive layer is 20 μm.

(Making adhesive layer B) First, 99 parts by weight of butyl acrylate (the same hereinafter), 1.0 part of 4-hydroxybutyl acrylate, 0.3 part of 2,2'-azobisisobutyronitrile and 100 parts of ethyl acetate are fed into a stirring blade and a thermometer. , Nitrogen introduction pipe and 4-necked flask with cooler. While slowly stirring the mixture, nitrogen was introduced into the flask for nitrogen substitution. By maintaining the liquid temperature in the flask at around 55°C for 4 hours, the polymerization reaction was carried out to prepare an acrylic polymer solution with a weight average molecular weight (Mw) of 1.65 million and Mw/Mn=3.7.

Next, for every 100 parts of the solid content of the acrylic polymer solution, 0.3 part of dibenzoyl peroxide (Nippon Oil & Fat Co., Ltd.: NYPER BMT) and 0.1 part of trimethylolpropane diisocyanate were blended. Toluene ester (MITSUI TAKEDA CHEMICALS, INC.: TAKENATE D110N) and 0.2 parts of silane coupling agent (manufactured by Luken Chemical Co., Ltd.: A-100, silane coupling agent containing acetyl acetyl group) to adjust the composition of the adhesive Things.

Next, the obtained solution was applied to one side of a separator (MRF38 manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.). The separation part is a polyethylene terephthalate film that has been treated with a silicone-based release agent. The obtained coating film was dried at 155° C. for 1 minute, thereby forming an adhesive layer B on the surface of the separator. The thickness of the adhesive layer is 20 μm.

(Making adhesive layer C) In the preparation of the adhesive layer A, the polymerization time of the acrylic polymer was set to 2 hours, except that the adhesive layer C was produced in the same manner. The weight average molecular weight (Mw) of the acrylic polymer is 1.9 million, and Mw/Mn=2.5.

(Making adhesive layer D) In making the adhesive layer A, the composition of the acrylic polymer was 80.9 parts of butyl acrylate, 18 parts of benzyl acrylate, 4.8 parts of acrylic acid, and 0.1 part of 4-hydroxybutyl acrylate. The adhesive layer D is prepared. The weight average molecular weight (Mw) of the acrylic polymer is 2.1 million, and Mw/Mn=4.0.

(Making adhesive layer E) First, a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler was fed with 71.9 parts of butyl acrylate, 18 parts of benzyl acrylate, 10 parts of acrylic acid, and 0.1 part of 4-hydroxybutyl acrylate to obtain Monomer mixture. With respect to 100 parts of the monomer mixture (solid content), 0.1 part of 2,2'-azobisisobutyronitrile as a polymerization initiator was fed together with 70 parts of ethyl acetate and 30 parts of toluene. While slowly stirring the mixture, nitrogen was introduced into the flask for nitrogen substitution. By maintaining the liquid temperature in the flask at around 55°C for 8 hours, the polymerization reaction was carried out to prepare an acrylic polymer solution with a weight average molecular weight (Mw) of 800,000 and Mw/Mn=3.6.

Next, with respect to 100 parts of the solid content of the acrylic polymer solution, 1 part of isocyanate crosslinking agent (Coronate L manufactured by Tosoh Co., Ltd., trimethylolpropane toluene diisocyanate), and benzyl peroxide were further blended. 0.1 part of 醯 (NYPER BMT manufactured by Nippon Oil & Fat Co., Ltd.) and 0.2 part of γ-glycidoxypropyl methoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-403) to prepare an acrylic adhesive composition Solution.

Next, the obtained solution was applied to one side of a separator (MRF38 manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.). The separation part is a polyethylene terephthalate film that has been treated with a silicone-based release agent. The obtained coating film was dried at 155° C. for 1 minute, thereby forming an adhesive layer E on the surface of the separator. The thickness of the adhesive layer is 20 μm.

[Example 1] (Preparation of polarizing film) The resin substrate is a long strip of amorphous isophthalic acid copolymer polyethylene terephthalate film (isophthalic acid-based modification degree: 5 mol%, thickness: 100μm). (Degree of modification = ethylene isophthalate unit / (ethylene terephthalate unit + ethylene isophthalate unit)) corona treatment is applied to one side of the resin substrate (treatment conditions: 55W・min/m ² ), and coat the corona treated surface at room temperature with an aqueous solution of PVA blended with 13 parts by weight of potassium iodide relative to PVA, wherein the aforementioned PVA is PVA (polymerization degree 4200, saponification degree 99.2 Mole%) 90 parts by weight and 10 parts by weight of acetyl modified PVA (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "GOHSEFIMER Z410"). After that, it was dried at 60° C. to form a PVA-based resin layer with a thickness of 13 μm to produce a laminate. In an oven at 130°C, the resulting laminate was uniaxially stretched 2.4 times at the free end in the longitudinal direction (long side direction) between rolls with different peripheral speeds (air-assisted stretch). Next, the layered body was immersed in an insoluble bath (a boric acid aqueous solution obtained by blending 4 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 40°C for 30 seconds (insoluble treatment). Next, adjust the concentration of a dyeing bath (an iodine aqueous solution obtained by mixing iodine and potassium iodide at a weight ratio of 1:7 with respect to 100 parts by weight of water) at a liquid temperature of 30°C and immerse it in it for 60 seconds to achieve a specified transmittance (Dyeing treatment). Next, it was immersed in a cross-linking bath (a boric acid aqueous solution obtained by mixing 3 parts by weight of potassium iodide and 5 parts by weight of boric acid with respect to 100 parts by weight of water with a liquid temperature of 40°C) for 30 seconds (cross-linking treatment) . Then, while immersing the layered body in a boric acid aqueous solution (boric acid concentration of 3.0% by weight) at a liquid temperature of 70°C, uniaxially stretched in the longitudinal direction (longitudinal direction) between rolls with different peripheral speeds to increase the total stretch magnification 5.5 times (extended in water). After that, the layered body was immersed in a washing bath (an aqueous solution obtained by mixing 4 parts by weight of potassium iodide with respect to 100 parts by weight of water with a liquid temperature of 20°C) (washing treatment). After that, while drying in an oven kept at 90°C (drying treatment), the temperature of the contact surface is passed through a metal roll made of SUS kept at 75°C for 2 seconds or longer (hot roll drying treatment). Through the above procedures, a polarizing film with a thickness of 5.4 μm was obtained on the resin substrate.

(Preparation of a polarizing film laminate) A cycloolefin-based film (made by Zeon, Japan, ZT12, 18 μm) as a polarizing film protective film was bonded to the surface of the obtained polarizing film on the opposite side to the resin substrate through an ultraviolet curable adhesive. Specifically, it is applied so that the total thickness of the curable adhesive described below becomes 1.0 μm, and is joined using a rolling mill. Thereafter, UV rays were irradiated from the side of the cycloolefin-based film to cure the adhesive. Next, the resin substrate is peeled off, and a polarizing film laminate containing a cycloolefin-based polarizing protective film and a polarizing film is obtained. The details of the hardening adhesive are as follows. 40 parts by weight of N-Hydroxyethyl acrylamide (HEAA), 60 parts by weight of acrylophrine (ACMO), and 3 parts by weight of photoinitiator "IRGACURE 819" (manufactured by BASF) were mixed to prepare an adhesive . It is coated on the polarizing film so that the thickness of the adhesive layer after curing becomes 1.0 μm, and ultraviolet rays are irradiated as active energy rays to cure the adhesive. Ultraviolet radiation uses a gallium-filled metal halide lamp, irradiation device: Light HAMMER10 manufactured by Fusion UV Systems, Inc., bulb: V bulb, peak illuminance: 1600mW/cm ² , cumulative irradiation amount 1000/mJ/cm ² (wavelength 380~440nm), the illuminance of ultraviolet rays is measured using the Sola-Check system manufactured by Solarell.

(Remove the polarizing film) Using cyclohexane as a solvent, the polarizing film was taken out from the polarizing film laminate to measure the iodine concentration of the polarizing film.

(Making a polarizing film laminate with an adhesive layer) By transferring the adhesive layer A to the surface of the polarizing film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Example 1 was produced.

[Example 2] When producing the polarizing film of Example 1, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. The other conditions are the same as in Example 1.

[Example 3] When producing the polarizing film of Example 1, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. When the polarizing film laminate of Example 1 was produced, a cycloolefin-based film (manufactured by Zeon Corporation, ZF12, 13 μm) was joined as a polarizing film protective film. The other conditions are the same as in Example 1.

[Example 4] When the polarizing film laminate of Example 1 was produced, a cellulose triacetate film-based film (TJ40UL manufactured by Fujifilm Corporation, thickness 40 μm) was bonded as a protective film for the polarizing film. In addition, when producing the polarizing film of Example 1, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration. The other conditions are the same as in Example 1.

[Example 5] When producing the polarizing film laminate of Example 1, as the polarizing film protective film, a transparent protective film (manufactured by Nitto Denko Corporation) with a thickness of 40 μm composed of a modified acrylic polymer having a lactone ring structure was joined. In addition, when producing the polarizing film of Example 1, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration. The other conditions are the same as in Example 1.

[Example 6] (Making polarizing film) The PVA film with an average degree of polymerization of 2700 and a thickness of 30μm is stretched and transported between rollers with different peripheral speed ratios. First, while immersing in a water bath at 30°C for 1 minute to swell the PVA film, it stretched 1.2 times in the conveying direction, and then immersed in an aqueous solution of potassium iodide (0.03% by weight) and iodine (0.3% by weight) (liquid temperature of 30°C) ) In 1 minute, stretch 3 times in the conveying direction while dyeing (based on unstretched film). Next, while immersing the stretched film in an aqueous solution (bath) of boric acid (4% by weight), potassium iodide (5% by weight), and zinc sulfate (3.5% by weight) for 30 seconds, it was stretched 6 times in the conveying direction (with The unstretched film is the basis). After stretching, it was dried in an oven at 40° C. for 3 minutes to obtain a polarizing film of 12.0 μm.

(Production of polarizing film laminate) Adhesives are used in a weight ratio of 3:1 containing polyvinyl alcohol resin containing acetyl acetyl groups (average degree of polymerization 1200, saponification degree 98.5 mol%, acetyl acetylation degree 5 Mole%) and methylol melamine in water. Using this adhesive, a transparent protective film with a thickness of 20μm composed of a modified acrylic polymer having a lactone ring structure was bonded to one side of the polarizing film using a roll laminator at a temperature of 30°C (Nitto Denko Corporation Made), and after bonding a 25μm-thick tri-cellulose acetate film (manufactured by Konica Minolta, trade name "KC2UA") on the other side to form a 2μm-thick hard coat layer (HC) with a 27μm-thick transparent protective film, Continue heating and drying in an oven at 70°C for 5 minutes to obtain a polarizing film laminate in which a transparent protective film is bonded to both sides of the polarizing film. The hard coat layer is formed by the following method. First, prepare the hard coat layer forming material. It is based on a resin solution (made by DIC (stock), trade name "UNIDIC 17-806") made by dissolving ultraviolet curable resin monomers or oligomers mainly composed of urethane acrylate into butyl acetate. ", the solid content concentration is 80% by weight), per 100 parts by weight of the solid content in the solution, 5 parts by weight of a photopolymerization initiator (made by BASF, product name "IRGACURE 906") and a leveling agent are added (DIC Co., Ltd., product name "GRANDIC PC4100") After 0.01 parts by weight, cyclopentanone is added to the above-mentioned mixed solution at a ratio of 45:55 so that the solid content in the above-mentioned solution becomes 36% by weight. (Hereinafter referred to as "CPN") and propylene glycol monomethyl ether (hereinafter referred to as "PGM") were produced by this. The hard coat layer forming material produced as described above is applied to the transparent protective film so that the thickness of the hard coat layer after hardening becomes 2 μm to form a coating film. Next, it was dried at 90°C for 1 minute, and then irradiated with a high-pressure mercury lamp with a cumulative light intensity of 300 mJ/cm ² of ultraviolet rays to cure the coating film. (Removing the polarizing film) Using dichloromethane and methyl ethyl ketone as a solvent, the polarizing film was taken out from the polarizing film laminate to measure the iodine concentration of the polarizing film.

(Making a polarizing film laminate with an adhesive layer) By transferring the adhesive layer A to the surface of the acrylic transparent protective film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Example 6 was produced.

[Example 7] When producing the polarizing film of Example 6, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration. In addition, when the polarizing film laminate of Example 6 was produced, on one side of the obtained polarizing film, a transparent protective film (Nitto) composed of a modified acrylic polymer having a lactone ring structure was joined as a polarizing film protective film. Denko Corporation), and a 40 μm thick tri-cellulose acetate film (manufactured by Konica Minolta, trade name "KC4UY") was bonded to the other side to form a transparent protective film with a thickness of 9 μm and a thickness of 49 μm with HC. The other conditions are the same as in Example 6.

[Example 8] The adhesive layer C in Example 7 was transferred to the surface of the acrylic transparent protective film of the polarizing film laminate, except that the adhesive layer-attached polarizing film laminate was produced in the same manner.

[Example 9] When producing the polarizing film of Example 6, the PVA film with a thickness of 45 μm was stretched and transported in the stretching process to obtain a polarizing film of 18.0 μm, and the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration. In addition, when the polarizing film laminate of Example 6 was produced, on one side of the obtained polarizing film, a transparent protective film of 30 μm thick composed of a modified acrylic polymer having a lactone ring structure was joined as a polarizing film protective film ( Nitto Denko Corporation), and a cellulose triacetate film-based film (Fujifilm Corporation TJ40UL, thickness 40 μm) was bonded to the other side. The other conditions are the same as in Example 6.

[Example 10] ~ [Example 13] When producing the polarizing film of Example 9, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. The other conditions are the same as in Example 9.

[Example 14] The adhesive layer C in Example 9 was transferred to the surface of the acrylic transparent protective film of the polarizing film laminate, except that the adhesive layer-attached polarizing film laminate was produced in the same manner.

[Example 15] The adhesive layer D in Example 9 was transferred to the surface of the acrylic transparent protective film of the polarizing film laminate, except that the adhesive layer-attached polarizing film laminate was produced in the same manner.

[Comparative example 1]~[Comparative example 2] When producing the polarizing film of Example 1, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. In addition, by transferring the adhesive layer B to the surface of the polarizing film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Comparative Examples 1 and 2 was produced. The other conditions are the same as in Example 1.

[Comparative example 3]~[Comparative example 4] When producing the polarizing film of Example 6, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. And, by transferring the adhesive layer B to the surface of the acrylic transparent protective film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Comparative Examples 3 and 4 was produced. The other conditions are the same as in Example 6.

[Comparative Example 5] When producing the polarizing film of Example 7, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. Furthermore, by transferring the adhesive layer B to the surface of the acrylic transparent protective film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Comparative Example 5 was produced. The other conditions are the same as in Example 7.

[Comparative Example 6] When producing the polarizing film of Example 9, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. Furthermore, by transferring the adhesive layer B to the surface of the acrylic transparent protective film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Comparative Example 6 was produced. The other conditions are the same as in Example 9.

[Comparative Example 7] (Making polarizing film) When the polarizing film of Example 9 was produced, a PVA film with a thickness of 60 μm was stretched and transported in a stretching process to obtain a polarizing film of 22.0 μm. In the dyeing process, the concentration of the iodine aqueous solution and the immersion time are adjusted to change the iodine concentration, and the thickness of the polarizing film protective film is adjusted to change the moisture content of the polarizing film laminate. The other conditions are the same as in Example 9. (Making polarizing film laminate) On one side of the obtained polarizing film, a transparent protective film (manufactured by Nitto Denko Corporation) with a thickness of 30 μm composed of a modified acrylic polymer having a lactone ring structure was bonded as a protective film of the polarizing film, and bonded to the other side with a thickness of 40 μm Third, a cellulose acetate film (manufactured by Konica Minolta, trade name "KC4UY") is formed with a transparent protective film of HC with a thickness of 9 μm and a thickness of 49 μm. The other processing is the same as in Example 9. (Remove the polarizing film) The extraction conditions are the same as in Example 9. (Making a polarizing film laminate with an adhesive layer) By transferring the adhesive layer B to the surface of the acrylic transparent protective film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Comparative Example 7 was produced.

[Comparative Example 8] When producing the polarizing film of Comparative Example 7, the concentration of the iodine aqueous solution and the immersion time were adjusted during the dyeing process to change the iodine concentration, and the thickness of the polarizing film protective film was adjusted to change the moisture content of the polarizing film laminate. And, on one side of the polarizing film, a transparent protective film (manufactured by Nitto Denko Corporation) with a thickness of 20 μm composed of a modified acrylic polymer having a lactone ring structure was joined as a protective film of the polarizing film. The other conditions are the same as in Comparative Example 7.

[Comparative Example 9] When the polarizing film of Example 9 was produced, a PVA film with a thickness of 75 μm was stretched and transported in a stretching process to obtain a polarizing film of 28 μm. In the dyeing process, the concentration of the iodine aqueous solution and the immersion time are adjusted to change the iodine concentration, and the thickness of the polarizing film protective film is adjusted to change the moisture content of the polarizing film laminate. Furthermore, by transferring the adhesive layer B to the surface of the acrylic transparent protective film of the polarizing film laminate, the adhesive layer-attached polarizing film laminate of Comparative Example 9 was produced. The other conditions are the same as in Example 9.

[Comparative Example 10] The adhesive layer D of Comparative Example 9 was transferred to the surface of the acrylic transparent protective film of the polarizing film laminate, and the adhesive layer-attached polarizing film laminate of Comparative Example 10 was produced in the same manner.

[Comparative Example 11] The adhesive layer E of Comparative Example 6 was transferred to the surface of the acrylic transparent protective film of the polarizing film laminate, and the adhesive layer-attached polarizing film laminate of Comparative Example 11 was produced in the same manner.

4-1. Reliability test Using the polarizing film laminate 12 obtained in the Examples and Comparative Examples, as shown in Fig. 4, the adhesive 11, 13 laminated glass plates (glass slides made by Songnang Glass, model: S2000423, specifications) were penetrated on both sides of the polarizing film laminate 12, respectively. : Water-edge mill 65×165mm, thickness 1.3mm), and use the obtained as a sample.

As the adhesive, CS9868US (manufactured by Nitto Denko Corporation) with a thickness of 200 μm was used on the side where the adhesive layers A to D were not provided in the polarizing film laminate.

The sample was placed at 95°C for 250 hours (95°C/250H) to evaluate its fading and heating red change, and after standing at 95°C for 500 hours (95°C/500H), the polyethylenization was evaluated.

4-2. Evaluation criteria The evaluation criteria for polyolefination, heating red change, and discoloration are described below.

<Polyolefinization> The monomer transmittance of the sample was measured before and after the heating test at 95°C/500H, and the monomer transmittance change ΔTs was obtained by the following formula. (Formula) ΔTs _{=Ts 500- Ts 0} Here, Ts ₀ is the transmittance of the monomer before heating the sample, and Ts ₅₀₀ is the transmittance of the monomer after heating at 95°C/500H. If the change ΔTs is a negative value, the sample is evaluated as "polyolefination (decrease in monomer transmittance)". In other words, when the transmittance of the monomer after heating at 95° C./500 hours is the same as or greater than the transmittance of the monomer before heating, it is estimated that there is no problem of polyalkylene. The monomer transmittance was measured with a spectrophotometer (product name "DOT-3" manufactured by Murakami Color Institute of Technology Co., Ltd.) for the above-mentioned sample. In addition, the transmittance of the monomer can be obtained according to JlS Z 8701.

<Fading, heating red change> Before and after the heating test at 95℃/250H, arrange the sample into cross-polarized light and use the above-mentioned spectrophotometer to measure the cross-transmittance (%) of wavelength 410nm and wavelength 700nm respectively, and obtain them separately The amount of change ΔHs ₄₁₀ and ΔHs ₇₀₀ . Those who meet all of the following two conditions are evaluated as "fading" of the sample.・The amount of change ΔHs ₄₁₀ is more than 1%. The amount of change ΔHs ₇₀₀ is more than 5%. In other words, after heating at 95°C/500 hours, the change in orthogonal transmittance at a wavelength of 410nm is less than 1%, and at a wavelength of 700nm When the change of the cross-transmittance below is less than 5%, it is estimated that there is no fading problem. In addition, the one that satisfies the following conditions is evaluated as the "heating red change" of the sample.・The amount of change ΔHs _{410 is} less than 1%. The amount of change ΔHs ₇₀₀ is more than 5%. In other words, after heating at 95°C/500 hours, the change in orthogonal transmittance at a wavelength of 410nm is above 1% and at a wavelength of 700nm When the change in cross-transmittance below is less than 5%, it is estimated that there is no problem of heating red change.

＜Adhesion durability＞ The polarizing film laminate with the adhesive layer was cut into a length of 420mm×320mm in width, and then attached to both sides of an alkali-free glass plate with a thickness of 0.7mm using a laminator. Next, autoclave treatment was performed at 50°C and 5 atm for 15 minutes to completely adhere the above-mentioned sample to the alkali-free glass plate. After the sample subjected to the above treatment was treated at 95°C for 500 hours (heating test), the state of foaming, peeling and embossing was evaluated visually according to the following criteria. "◎": No foaming, peeling, embossing, etc., no appearance changes "〇": Although there is very little peeling or foaming at the end, there is no problem in actual use "△": There is peeling or foaming at the end, but as long as it is not used for special purposes, there is no problem in actual use "×": There is significant peeling or foaming at the end, which is problematic in actual use

＜Heavy workability＞ The polarizing film laminate with the adhesive layer obtained in the Examples and Comparative Examples was cut to a length of 200 mm × a width of 100 mm to prepare samples. This sample was attached to alkali-free glass (trade name: EG-XG, manufactured by Corning Incorporated) with a thickness of 0.7 mm using a laminating machine. Next, autoclave treatment was performed at 50°C and 0.5 MPa for 15 minutes to completely adhere the above-mentioned sample. For this sample, the sample was peeled from the alkali-free glass by hand, and the reworkability was evaluated according to the following criteria. The evaluation of heavy workability is implemented by making 3 pieces according to the above procedure and repeating it 3 times. ⊚: No glue residue or film breakage occurred in all 3 sheets, and they could be peeled off well. ○: A part of the film was broken in 3 sheets, but it can be peeled off by peeling it off again. △: All three films are broken, but they can be peeled off when they are peeled off again. ×: Glue residue was generated in all 3 sheets, or the film was broken regardless of how many times it was peeled off.

The evaluation results of each Example and Comparative Example are listed in Table 2 below. [Table 2]

5. Integration of evaluation results FIG. 5 is a graph in which the results of Examples and Comparative Examples (except Comparative Example 11) are plotted in an xy orthogonal coordinate system. The x-axis (horizontal axis) represents the iodine concentration (wt.%) of the polarizing film, and the y-axis (vertical axis) represents the moisture content (g/m ² ) of the polarizing film laminate.

(1) Judging from the drawing results and technical common sense, it can generally be said that when the iodine concentration is small and the water content is too small, the problem of heating red change that occurs at high temperatures is likely to occur; on the other hand, when the iodine concentration is large and When the moisture content is too large, the problems of polyolefination and fading are likely to occur. Moreover, it can be said that when the iodine concentration is small and the moisture content is too large, the problem of fading under high temperature and high humidity conditions is likely to occur. At this time, as the iodine concentration increases, the problem of polyolefination is more likely to occur. Especially between fading and polyolefination, the transition region between these areas can also be seen (Comparative Examples 13, 15). On the other hand, it can be seen that when the iodine concentration and moisture content are controlled within a predetermined area, the heating red change, polyolefinization and color fading can all be solved in a comprehensive manner. For example, the results of the examples are all located on the upper side of the dividing line "α" that is y=(1043-125x)/240 and on the lower side of the dividing line "β" that is y=(379-33x)/70 , The dividing line "α" is the coordinate point (hereinafter referred to as the first coordinate point) around the plot showing the result of Example 3 with the smallest moisture content, that is, the iodine concentration of 7.0wt.% and the moisture content of 0.7g/m ² ), and the coordinates around the plot showing the results of Example 9 with the minimum iodine concentration, that is, the iodine concentration 2.2wt.% and the water content 3.2g/m ² coordinate point (hereinafter referred to as the second coordinate point), and the dividing line " β” is the coordinate point (hereinafter referred to as the 4th coordinate point) of the results of Example 8 showing the maximum moisture content, that is, the iodine concentration of 3.0 wt.% and the moisture content of 4.0 g/m ^{2 (hereinafter referred to as the fourth coordinate point), and} The maximum iodine concentration of the result of Example 2 is plotted around the coordinate point (hereinafter referred to as the fifth coordinate point) of the iodine concentration of 10.0 wt.% and the moisture content of 0.7 g/m ^2. Therefore, the area separated by the dividing lines "α" and "β" can be regarded as a line showing the necessary requirements for comprehensively solving the heating red change, polyolefinization, and color fading. In addition, the separation lines "α" and "β" have nothing to do with the film thickness of the polarizing film, and furthermore, they are applicable to all polarizing films having a film thickness of about 4-20 μm. In addition, in Comparative Example 6 using adhesive B (the amount of acid in the total monomer components constituting the adhesive polymer: 0% by weight), although the heating red change was observed, the problem of polyalkenization did not occur, compared to Therefore, in Comparative Example 11 in which the adhesive was changed to the adhesive E (the amount of acid components in the total monomer components constituting the adhesive: 10% by weight), polyethylenization was confirmed. Therefore, we speculate that if an acid component is used in the monomer component of the adhesive polymer in excess of a predetermined amount, polyolefinization will be promoted.

(2) Also, it can be known from the drawing results and technical common sense that especially all polarizing films with a film thickness of about 4-20μm, when the iodine concentration and the moisture content of the polarizing film laminate are contained in the area enclosed by a to e , You can solve all of "polyalkenization", "fading" and "heating red change". In more detail, this area is the area surrounded by the following line segment: connecting the iodine concentration of 7.0wt.% and the moisture content of 0.7g /m ² The first coordinate point ("a" in the figure) and the first line segment of the second coordinate point ("b" in the figure) with an iodine concentration of 2.2wt.% and a moisture content of 3.2g/m ² the second coordinate point "b" with iodine concentration 2.2wt.% and the amount of water 4.0g / m ² of a third coordinate point ( "c" in the FIG.) of the second line segment connecting the third point coordinate "c" with iodine concentration of 3.0wt.% and the amount of water 4.0g / m ² of a fourth coordinate point ( "d" of the figure) the third line segment connecting the fourth point coordinate "d" with iodine concentration 10.0wt.% and water content 0.7 The fourth line segment of the fifth coordinate point ("e" in the figure) of g/m ² and the fifth line segment connecting the first coordinate point "a" and the fifth coordinate point "e".

(3) It can also be seen that, especially for a polarizing film with a film thickness of about 11 to 20 μm, when the iodine concentration and the moisture content of the polarizing film laminate are contained in the area surrounded by f, b, c, d, and g, that is "Polyolefinization", "fading" and "heating red change" can be solved in a comprehensive way. In more detail, this area is the area surrounded by the following line segment: connecting the iodine concentration of 4.5wt.% and the water content of 2.0g/m ^2nd coordinate point 6 ("f" in the figure) and the 6th line segment of the 2nd coordinate point "b", the 2nd line segment connecting the 2nd coordinate point "b" and the 3rd coordinate point "c", and the second line segment connecting the second coordinate point "b" and the third coordinate point "c". The 3rd line segment between the 3 coordinate point "c" and the 4th coordinate point "d", the 7th coordinate point connecting the 4th coordinate point "d" with the iodine concentration of 4.5wt.% and the moisture content of 3.3g/m ² (in the figure The 7th line segment of "g") and the 8th line segment connecting the 6th coordinate point "f" and the 7th coordinate point "g". We speculate that especially at the sixth coordinate point "f" is the iodine concentration 4.0wt.% and the moisture content is 2.3g/m ² the coordinate point "f-1", and the seventh coordinate point "g" is the iodine concentration 4.0wt. When the coordinate point "g-1" of .% and the moisture content of 3.5g/m ² is used, ideal results can be obtained in particular. In addition, it is estimated that a polarizing film with a film thickness of about 11 to 20 μm is surrounded by f, b, c, d, and g in the iodine concentration and the moisture content of the polarizing film laminate and separated by a line segment connecting h and i When it is in the area, better results can be obtained in all aspects of "polyalkenization", "fading" and "heating red change". In more detail, this area is the area surrounded by the following line segment: the connected iodine concentration is 3.3wt. % And moisture content of 2.6g/m ² of the 8th coordinate point ("h" in the figure) and the 9th line segment of the second coordinate point "b", connecting the second coordinate point "b" and the third coordinate point "c" The second line segment connecting the third coordinate point “c” and the fourth coordinate point “d”, the seventh line segment connecting the fourth coordinate point “d” and the seventh coordinate point “g”, and the seventh line segment connecting the fourth coordinate point “d” and the seventh coordinate point “g”. The 8th line segment between the 6th coordinate point "f" and the 7th coordinate point "g", and the 9th coordinate point connecting the 8th coordinate point "h" with the iodine concentration of 6.0wt.% and the moisture content of 2.6g/m ² (Figure The 10th line segment of "i").

(4) It can be seen that, in particular, a polarizing film having a film thickness of about 4 to 11 μm, preferably a film thickness of 4 to 7 μm, and more preferably a film thickness of 4.5 to 6 μm, in terms of the iodine concentration and the moisture content of the polarizing film laminate When it is included in the area surrounded by a, h, i, and e, all "polyolefinization", "fading" and "heating red change" can be solved in a comprehensive manner. In more detail, this area is surrounded by the following line segment Area: The 11th line segment connecting the 1st coordinate point "a" and the 8th coordinate point "h", the 10th line segment connecting the 8th coordinate point "h" and the 9th coordinate point "i", and the 9th coordinate point " The 12th line segment between i" and the 5th coordinate point "e", and the 5th line segment connecting the first coordinate point "a" and the 5th coordinate point "e". In particular, it is speculated that the 8th coordinate point "h" is the 6th coordinate point "f", and the 9th coordinate point "i" is the 10th coordinate point ^{with an iodine concentration of 7.2wt.% and a moisture content of 2.0g/m 2 (Figure} In the case of "j"), ideal results can be obtained in particular. In addition, it is estimated that a polarizing film having a film thickness of about 4 to 11 μm, preferably a film thickness of 4 to 7 μm, and more preferably a film thickness of 4.5 to 6 μm, is contained in a, In the area enclosed by k, i, and e, better results can be obtained in all aspects of "polyolefinization", "fading" and "heating red change". In more detail, this area is the area surrounded by the following line segment : The 13th line segment connecting the first coordinate point "a" with the iodine concentration 6.0wt.% and the moisture content of 1.2g/m ² ("k" in the figure), and the 11th coordinate point "k" The 14th line segment with the 9th coordinate point "i", the 12th line segment connecting the 9th coordinate point "i" and the 5th coordinate point "e", and the first coordinate point "a" and the 5th coordinate point "e""The 5th line segment. Especially at the 11 presumed coordinate point "k" is an iodine concentration of 6.5wt.% And the amount of water 1.0g / m ² of the coordinate point (k-1), and the ninth coordinate point "i" is an iodine concentration of 6.5wt.% And when the water content is 2.3g/m ² coordinate point (i-1), more ideal results can be obtained.

1: Optical display panel 2: PVA layer 6: Amorphous PET substrate 7: Laminated body including PVA layer 8: Extended layered body 8': Coil of extended laminate 9: Colored layered body 10: Optical display unit 10a: One side of the optical display unit 10b: The other side of the optical display unit 11: Transparent adhesive 12: Polarized film laminate 13: Transparent adhesive 14: Transparent cover plate 16: Transparent adhesive 17: Another polarizing film laminate 18: Light source (backlight part) 20: Laminated body making device 21: Coating mechanism 22: Drying mechanism 23: Surface modification treatment device 30: Aerial auxiliary extension processing device 31: Extension mechanism 32: Coiling device 33: Oven 40: Dyeing device 41: staining solution 42: dye bath 43: release device 50: Boric acid water treatment device 51: Boric acid aqueous solution 52: Boric acid bath 53: extension mechanism 60: Optical film laminate 80: Washing device 81: washing liquid 90: Drying device 91: Coiling device 120: Polarizing film 121: Polarizing film protective film 122: Polarizing film protective film (A): Laminated body production processing (B): Aerial auxiliary extension processing (C): Dyeing treatment (D): Boric acid water extension treatment (G): Washing treatment (H): Dry treatment

FIG. 1 is a schematic diagram showing the layer structure of an optical display panel. Fig. 2 is a diagram illustrating an example of a method of manufacturing a polarizing film. Fig. 3 is a diagram showing a calibration curve used to obtain the iodine concentration of the polarizing film. Figure 4 is a diagram showing the structure used for reliability testing. Fig. 5 is a graph plotting the results of Examples and Comparative Examples.

Claims (16)

A polarizing film laminate, a polarizing film laminate with an adhesive layer, comprising a polarizing film containing a polyvinyl alcohol resin, and an adhesive layer, the adhesive layer being directly or via an optically transparent polarizing film The protective film is provided on at least one side of the polarizing film; the polarizing film laminate is characterized in that: the adhesive layer includes an adhesive polymer, the acid component of the adhesive polymer is copolymerized, and constitutes the adhesive polymer The amount of the acid component in the total monomer component is less than 5% by weight; when the x-axis is the iodine concentration (wt.%) of the aforementioned polarizing film, and the y-axis is the moisture content of the aforementioned polarizing film laminate (g/ The xy orthogonal coordinate system of m ² ) has the iodine concentration and water content included in the area surrounded by the following line segment: The first coordinate point ^{connecting the iodine concentration 7.0wt.% and the water content 0.7g/m 2 and iodine} The first line segment of the second coordinate point with a concentration of 2.2wt.% and a moisture content of 3.2g/m ² connecting the aforementioned second coordinate point with the third coordinate point with an iodine concentration of 2.2wt.% and a moisture content of 4.0g/m ² second line segment, the third line segment connecting the third point and the coordinate iodine concentration 3.0wt.% and the amount of water 4.0g / m ² of a fourth coordinate point connecting point and the fourth coordinate iodine concentration 10.0wt.% water and The fourth line segment of the fifth coordinate point with an amount of 0.7g/m ² and the fifth line segment connecting the aforementioned first coordinate point and the aforementioned fifth coordinate point. The polarizing film laminate of claim 1, wherein the polydispersity index (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the aforementioned adhesive polymer is 3.0 or less. The polarizing film laminate of claim 1 or 2, wherein the film thickness of the aforementioned polarizing film is 4-20 μm. A polarizing film laminate, a polarizing film laminate with an adhesive layer, comprising a polarizing film containing a polyvinyl alcohol resin, and an adhesive layer, the adhesive layer being directly or via an optically transparent polarizing film The protective film is provided on at least one side of the polarizing film; the polarizing film laminate is characterized in that: the adhesive layer includes an adhesive polymer, the acid component of the adhesive polymer is copolymerized, and constitutes the adhesive polymer The amount of the acid component in the total monomer component is less than 5% by weight; when the x-axis is the iodine concentration (wt.%) of the aforementioned polarizing film, and the y-axis is the moisture content of the aforementioned polarizing film laminate (g/ The xy orthogonal coordinate system of m ² ) has the iodine concentration and water content contained in the area enclosed by the following line segment: The sixth coordinate point and iodine ^{connecting the iodine concentration of 4.5wt.% and the water content of 2.0g/m 2} The 6th line segment of the second coordinate point with a concentration of 2.2wt.% and a moisture content of 3.2g/m ² connecting the aforementioned second coordinate point with the third coordinate point with an iodine concentration of 2.2wt.% and a moisture content of 4.0g/m ² second line segment, the third line segment connecting the third point and the coordinate iodine concentration 3.0wt.% and the amount of water 4.0g / m ² of a fourth coordinate point connecting point and the fourth coordinate iodine concentration 4.5wt.% water and The seventh line segment of the seventh coordinate point with an amount of 3.3 g/m ^{2 and} the eighth line segment connecting the aforementioned sixth coordinate point and the aforementioned seventh coordinate point. The requested item polarizing film of the laminate 4, wherein the sixth coordinate point iodine concentration of 4.0wt.% And the amount of water 2.3g / m ² of the coordinate point, and the coordinate point 7 iodine concentration of 4.0wt.% Water and Coordinate point of 3.5g/m ^2. The polarizing film laminate of claim 4 or 5, wherein the film thickness of the aforementioned polarizing film is 11-20 μm. A polarizing film laminate, a polarizing film laminate with an adhesive layer, comprising a polarizing film containing a polyvinyl alcohol resin, and an adhesive layer, the adhesive layer being protected directly or via an optically transparent polarizing film The film is arranged on at least one side of the polarizing film; the polarizing film laminate is characterized in that: the adhesive layer includes an adhesive polymer, and the acid component in the adhesive polymer is copolymerized and constitutes the total of the adhesive polymer The amount of the acid component in the monomer component is less than 5% by weight; Let the x-axis be the iodine concentration of the aforementioned polarizing film (wt.%) and the y-axis be the moisture content of the aforementioned polarizing film laminate (g/m ² ) The xy orthogonal coordinate system has the iodine concentration and water content included in the area enclosed by the following line segment: The first coordinate point and the iodine concentration ^{connecting the iodine concentration of 7.0wt.% and the water content of 0.7g/m 2} 3.3wt.% and the amount of water 2.6g / m of the coordinate point ⁸² of segment 11, connecting said first coordinate point and the eighth iodine concentration 6.0wt.% and the amount of water 2.6g / m ² of the ninth coordinate point the first line segment 510, connecting the coordinate point and the ninth iodine concentration 10.0wt.%, and water content 0.7g / m of the coordinate point ⁵² of segment 12, and connecting said first coordinate point and the coordinate point 5 Line segment. For example, the polarizing film laminate of claim 7, wherein the aforementioned 8th coordinate point is the 6th coordinate point with an iodine concentration of 4.5wt.% and a moisture content of 2.0g/m ² , and the aforementioned 9th coordinate point is an iodine concentration of 7.2wt.% And the 10th coordinate point with a water content of 2.0g/m ^2. The polarizing film laminate of claim 7 or 8, wherein the film thickness of the aforementioned polarizing film is 4-11 μm. The polarizing film laminate according to any one of claims 1 to 9, wherein the aforementioned polarizing film contains zinc. The polarizing film laminate of any one of claims 1 to 10 is composed of the polarizing film laminate of any of claims 1 to 10 and a glass plate laminated on both sides of the polarizing film laminate through an adhesive For the sample, the transmittance of the monomer after heating at 95°C/500 hours is the same as or greater than the transmittance of the monomer before heating. The polarizing film laminate of any one of claims 1 to 11 is composed of the polarizing film laminate of any of claims 1 to 11 and a glass plate laminated on both sides of the polarizing film laminate through an adhesive After the sample is heated at 95°C/500 hours, the change in orthogonal transmittance at a wavelength of 410nm is less than 1%, and the change in orthogonal transmittance at a wavelength of 700nm is less than 5%. The polarizing film laminate of any one of claims 1 to 11 is composed of the polarizing film laminate of any of claims 1 to 11 and a glass plate laminated on both sides of the polarizing film laminate through an adhesive After the sample is heated at 95℃/500 hours, the change in orthogonal transmittance at a wavelength of 410nm is more than 1%, and the change in orthogonal transmittance at a wavelength of 700nm is less than 5%. An optical display panel, characterized in that: It has: Optical display unit; For example, the polarizing film laminate of any one of claims 1 to 13 is bonded to one side of the aforementioned optical display unit directly or via other optical films; and The cover plate is optically transparent and is arranged along the polarizing film laminate on the opposite side of the polarizing film laminate from the optical display unit; and The optical display unit, the polarizing film laminate, and the transparent cover plate are bonded by a transparent adhesive layer, and the transparent adhesive layer is filled in a state in which no gaps are generated between them. Such as the optical display panel of claim 14, wherein the aforementioned transparent cover plate has the function of a capacitive touch sensor. The optical display panel of claim 15, wherein an ITO layer that becomes a component of a capacitive touch sensor is provided between the transparent cover plate and the polarizing film laminate.

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