TWI725142B - Manufacturing method of single-sided protective polarizing film with adhesive layer - Google Patents

Abstract

The present invention relates to a method for manufacturing a single-sided protective polarizing film with an adhesive layer. The single-sided protective polarizing film has a protective film on only one side of the polarizer, and the thickness of the polarizer is less than 10 μm and has a specific Optical properties, and the single-sided protective polarizing film with an adhesive layer has a transparent resin layer and an adhesive layer in sequence from the polarizer side of the single-sided protective polarizing film; the manufacturing method is implemented by implementing the following steps Step (1) and step (2) form a transparent resin layer and perform step (3) to form an adhesive layer to proceed: Step (1) is to transport the single-sided protective polarizing film while protecting the polarized light of the single-sided polarizing film The part side is coated with a coating liquid containing a resin component or a curable component, and the curable component can form a resin layer; step (2), which is to cure or harden the coating liquid after the aforementioned coating step (1) Step (3), which is to form an adhesive layer on the transparent resin layer without winding the obtained single-sided protective polarizing film with a transparent resin layer into a roll. Even when a thin one-sided protective film is used, a transparent resin layer can be stably formed and then an adhesive layer can be formed.

Description

Manufacturing method of single-sided protective polarizing film with adhesive layer

The invention relates to a method for manufacturing a single-sided protective polarizing film with an adhesive layer. The single-sided protective polarizing film with adhesive layer obtained by the aforementioned manufacturing method can be used alone or laminated to form an optical film to form image display devices such as liquid crystal display devices (LCD) and organic EL display devices.

The market for liquid crystal display devices for applications such as clocks, mobile phones, PDAs, notebook computers, computer monitors, DVD players, and TVs is rapidly expanding. The liquid crystal display device visualizes the polarization state through switching of the liquid crystal, and uses a polarizer based on its display principle.

As a polarizer, because of its high transmittance and high degree of polarization, the iodine-based polarizer is the most widely used, for example, a structure formed by making polyvinyl alcohol adsorb iodine and stretch it. This kind of polarizer has the shortcomings of extremely weak mechanical strength and shrinkage due to heat or moisture, resulting in a significant reduction in the polarizing function. Therefore, the prepared polarizer is immediately bonded to the protective film coated with the adhesive through the adhesive to form a polarizing film for use.

When attaching the aforementioned polarizing film to a liquid crystal cell or the like, an adhesive is usually used. In addition, since it has the advantages of instant fixation of the polarizing film, and no need for a drying step to fix the polarizing film, the adhesive is preliminarily provided on one side of the polarizing film as an adhesive layer. That is, in the adhesion of the polarizing film, a polarizing film with an adhesive layer is usually used.

On the other hand, image display devices such as liquid crystal display devices have advanced toward thinning, and thinning of polarizing films is also being required. Therefore, the thinning of the polarizer is also in progress (Patent Document 1). In addition, it can be thinned by using a single-sided protective polarizing film, which only has a protective film on one side of the polarizer, and no protective film on the other side. Compared with the two-sided protective polarizing film in which protective films are provided on both sides of the polarizer, the single-sided protective polarizing film can be thinner due to the lack of a layer of protective film.

On the other hand, a single-sided protective polarizing film has insufficient durability against the aforementioned thermal shock, so it has been proposed to provide a protective layer (transparent resin layer) on the side of the polarizer (Patent Documents 2 and 3).

Prior Art Documents Patent Documents Patent Document 1: Japanese Patent No. 4751481 Specification Patent Document 2: Japanese Patent Publication No. 2010-009027 Patent Document 3: Japanese Patent Publication No. 2013-160775

The problem to be solved by the invention Patent Documents 2 and 3 seek to reduce the thickness by using a single-sided protective polarizing film with a protective film on only one side of the polarizer. On the other hand, a protective layer is provided to prevent the use of single-sided protection. The occurrence of through cracks in the direction of the absorption axis of the polarizer caused by the polarizing film (the change in the shrinkage stress of the polarizer under the severe environment of thermal shock (for example, the thermal shock test between -30°C and 80°C) And cracks appearing integrally in the direction of the absorption axis of the polarizer). In addition, Patent Documents 2 and 3 describe that when a protective layer (transparent resin layer) is formed on a single-sided protective polarizing film, the forming material can be applied by various coating methods.

On the other hand, as mentioned above, the development of thinning has also occurred on the polarizer. When the polarizing member used in the polarizing film or the polarizing film with an adhesive layer is made thin (for example, when the thickness is 10 μm or less), the shrinkage stress change of the polarizing member becomes smaller. Therefore, it has been understood that if a thinned polarizer is used, the occurrence of the aforementioned through cracks can be suppressed.

However, in the single-sided protective polarizing film in which the occurrence of through cracks has been suppressed, or the polarizing film using its adhesive layer, when the optical characteristics are controlled as in Patent Document 1 and the polarizer is made thin (for example, , When the thickness is 10μm or less), when the single-sided protective polarizing film or the polarizing film with the adhesive layer of the film is subjected to mechanical impact (including the load caused by the convex fold on the polarizer side), it is known to be Very fine slits (hereinafter also referred to as nano slits) appear locally in the direction of the absorption axis of the polarizer. It is also known that the generation of the aforementioned nano-slits is independent of the size of the polarizing film. Furthermore, it is also known that when a double-sided protective polarizing film with protective films on both sides of the polarizer is used, the aforementioned nano-slit does not occur. In addition, it is known that when a through crack occurs in a polarizer, since the stress around the through crack is released, the through crack does not occur adjacent to each other, but nano-slits also occur adjacent to each other in addition to being generated alone. It is also known that through cracks have travel properties extending in the direction of the absorption axis of the polarizer where the cracks have occurred, but nano-slits have no such travel properties. It can be seen that the aforementioned nano-slit is a new problem that arises when the polarizer of the single-sided protective polarizing film in which the occurrence of through cracks has been suppressed has been thinned and the optical characteristics have been controlled within the desired range. It is known that the aforementioned through cracks are problems caused by different phenomena.

In addition, since the aforementioned nano slits are extremely thin, they cannot be detected under normal circumstances. Therefore, even if there are nano-slits in the polarizer, it is still difficult to confirm the defects caused by the light leakage of the single-sided protective polarizing film and the polarizing film with the adhesive layer using the film at a glance. In other words, the single-sided protective polarizing film is usually made into a long film and inspected for defects by automatic optical inspection. However, it is difficult to detect nano-slits as defects by this defect inspection. It is also known that the defects caused by the aforementioned nano-slits, when a single-sided protective polarizing film or a polarizing film with an adhesive layer is attached to the glass substrate of an image display panel, etc., and then placed in a heated environment, the nano-slits will go horizontally It expands and thus becomes detectable (for example, the presence or absence of the aforementioned light leakage).

Therefore, for a single-sided protective polarizing film with a polarizer thickness of 10 μm or less or a polarizing film with an adhesive layer using the film, it is desirable to suppress not only through cracks but also the occurrence of nano-slits. .

However, in the case of using a thin single-sided protective polarizing film, after the transparent resin layer is formed by the coating liquid of the protective layer (transparent resin layer), for example, in order to promote curing and obtain a desired film thickness Transparent resin layer and temporarily roll up the single-sided protective polarizing film with transparent resin layer into a roll shape, when you want to output the previously rolled single-sided protective polarizing film with transparent resin layer again to transfer to the next step of adhesion In the step of forming the agent layer, the single-sided protective polarizing film with a transparent resin layer may be agglomerated (the rolled films adhere to each other) during output, and the polarizer may be locally stressed. Therefore, the obtained roll of the single-sided protective polarizing film with a transparent resin layer increases the risk of nano-slits, or the output of the next step becomes difficult. On the other hand, after the transparent resin layer is formed, if the transparent resin layer is wound with a surface protective film attached to it, the blocking caused by the transparent resin layer can be avoided, but because the surface protective film will be peeled off The polarizing part is partially stressed, so the risk of nano-slits will increase.

The object of the present invention is to provide a method for manufacturing a single-sided protective polarizing film with an adhesive layer, which can stably form a transparent resin layer and then form an adhesive layer even when a thin single-sided protective film is used. At the same time, it can inhibit the occurrence of nano-slit.

Means for Solving the Problem After careful research by the inventors of the present case, it was found that the above-mentioned problem can be solved by the following manufacturing method of a single-sided protective polarizing film with an adhesive layer attached, and finally the present invention has been completed.

That is, the present invention relates to a method for manufacturing a single-sided protective polarizing film with an adhesive layer. The single-sided protective polarizing film has a protective film on only one side of the polarizer, and the single-sided protection of the adhesive layer The polarizing film has a transparent resin layer and an adhesive layer in sequence from the polarizer side of the single-sided protective polarizing film. The manufacturing method is characterized in that: the aforementioned polarizer contains polyvinyl alcohol-based resin, and has a thickness of 10 μm or less, and has a structure The optical characteristics expressed by monomer transmittance T and polarization degree P satisfy the condition of the following formula: P>-(10 ^0.929T-42.4 -1)×100 (only T<42.3), or P≧99.9 (only T≧42.3); The formation of the aforementioned transparent resin layer and adhesive layer is carried out by performing the following steps (1) and (2) to form the transparent resin layer and then performing step (3) to form the adhesive layer: Step (1) ), which is conveying the single-sided protective polarizing film while coating the polarizer side of the single-sided protective polarizing film with a coating solution containing a resin component or a curable component, and the curable component can constitute a resin layer; step (2), which is to cure or harden the aforementioned coating liquid after the aforementioned coating step (1); step (3), which is to not roll the obtained single-sided protective polarizing film with a transparent resin layer Under the condition, an adhesive layer is formed on the transparent resin layer.

In the manufacturing method of the aforementioned adhesive layer-attached single-sided protective polarizing film, after the aforementioned step (2) and before the aforementioned step (3), there may be a step (4), which is to measure the film thickness of the transparent resin layer in the conveying line. The aforementioned step (4) can be performed using an optical interference method using a polarizing element at the front end of the light source.

In the manufacturing method of the aforementioned single-sided protective polarizing film with an adhesive layer, a coating solution containing a resin component that has been dissolved or dispersed in water can be used as the coating solution of the aforementioned step (1), and in step (2) through Cured to form a transparent resin layer. The aforementioned resin-containing coating liquid is preferably an aqueous solution containing a polyvinyl alcohol-based resin.

In the aforementioned manufacturing method of the adhesive layer-attached single-sided protective polarizing film, the viscosity of the coating solution of the aforementioned step (1) at 25° C. is preferably 1000 mPa·s or less.

In the manufacturing method of the aforementioned single-sided protective polarizing film with an adhesive layer, the aforementioned polarizer preferably contains 20% by weight or less of boric acid relative to the total amount of the polarizer.

In the manufacturing method of the single-sided protective polarizing film with the adhesive layer, it can also be used in the adhesive layer separator. The single-sided protective polarizing film with an adhesive layer provided with a separator can be made into a winding.

Effect of the Invention The single-sided protective polarizing film with an adhesive layer obtained by the manufacturing method of the present invention is thinned by using a polarizer with a thickness of 10 μm or less. In addition, compared with the case where the thickness of the polarizer is high, the aforementioned thin polarizer with a thickness of 10 μm or less has a smaller change in shrinkage stress applied to the polarizer due to thermal shock, so that the occurrence of through cracks can be suppressed.

But on the other hand, thin polarizers with desired optical characteristics are prone to nano-slits in the polarizers. Nano-slits are considered to be used in the manufacturing steps of the polarizing film with the adhesive layer to be placed on the single-sided protective polarizing film, and in various steps after the polarizing film with the adhesive layer has been manufactured. It is generated when the aforementioned single-sided protective polarizing film or the polarizing film using the adhesive layer of the polarizing film is subjected to mechanical shock, and it is presumed that it is caused by a mechanism different from the through crack caused by thermal shock. In addition, when the single-sided protective polarizing film with the adhesive layer is attached to the glass substrate of the image display panel, etc., and then placed in a heated environment, the nanometer gap will expand in the lateral direction, and the aforementioned detection becomes possible. Defects caused by nano-slits (for example, whether there is light leakage as mentioned above).

The single-sided protective polarizing film with adhesive layer obtained by the manufacturing method of the present invention can suppress the occurrence of the aforementioned nano-slits by arranging a transparent resin layer on the other side of the polarizer (the side without the protective film).

According to the manufacturing method of the present invention, after the transparent resin layer is formed on the single-sided protective film using the thin polarizer through step (1) and step (2), "the resultant single-sided protective film with a transparent resin layer is not performed" The surface protection polarizing film is temporarily rolled into a roll, and the previously wound single-sided protection polarizing film with a transparent resin layer is output again.” Instead, it is transferred to step (3), where the transparent resin An adhesive layer is formed on the layer. In this way, since the manufacturing method of the present invention does not have the step of winding and outputting the single-sided protective polarizing film with a transparent resin layer, it will not cause the nano-slits caused by agglomeration of the single-sided protective polarizing film with a transparent resin layer. The risk of occurrence is increased, and a single-sided protective polarizing film with an adhesive layer can be manufactured continuously and stably.

Furthermore, in the manufacturing method of the present invention, after step (2) and before step (3), step (4) may be provided to measure the thickness of the transparent resin layer of the single-sided protective polarizing film with a transparent resin layer. Using the aforementioned step (4), even if the single-sided protective polarizing film with a transparent resin layer is not rolled into a roll, the thickness of the transparent resin layer can be measured stably and managed so that the transparent resin layer is as desired Film thickness. As a result, since it is not necessary to confirm the film thickness management offline, the productivity is improved.

Hereinafter, the steps (1) to (3) of the manufacturing method of the adhesive layer single-sided protective polarizing film of the present invention will be described with reference to FIG. 1.

In the coating step (1), the coating liquid 2'is coated on the single-sided protective polarizing film 1 that is being transported. The single-sided protective polarizing film 1 has a protective film 20 on only one side of the polarizer 10, and is represented by the structure of the polarizer 10/protective film 20. In FIG. 1, the aforementioned coating liquid 2'is shown in a state that it has been (directly) coated on the polarizer of the single-sided protective polarizing film 1. In addition, the aforementioned single-sided protective polarizing film 1 is generally preferably transported at 5-50 m/min, and further preferably transported at 10-40 m/min. In the curing or hardening step (2), a transparent resin layer 2 is formed from the aforementioned coating solution 2', and a single-sided protective polarizing film A with a transparent resin layer is obtained. Then perform step (3), without winding the single-sided protective polarizing film A with a transparent resin layer into a roll, form an adhesive layer 3 on the transparent resin layer 2 to produce a single-sided protective polarizer with an adhesive layer Film B.

As shown in FIG. 1, in the manufacturing method of the present invention, after the aforementioned step (2) and before the aforementioned step (3), there may be a step (4), which is to measure the film thickness of the transparent resin layer in the conveying line . The aforementioned step (4) can be performed as shown in FIG. 2 by using a polarizer 41 between the light source 40 and the single-sided protective polarizing film and using an optical interference method. The light source 40 is set to be perpendicular to the transparent resin layer 2 side of the single-sided protective polarizing film A with a transparent resin layer. A polarizer 41 is used between the light source 40 and the single-sided protective polarizing film A with a transparent resin layer, so that the light source 40 and the polarizer 10 of the single-sided protective polarizing film A with a transparent resin layer are perpendicular to the absorption axis. The thickness of the transparent resin layer 2 was measured by an optical interference method.

In addition, although not shown, a separator can be provided on the adhesive layer of the one-side protective polarizing film B of the adhesive layer of the present invention. In addition, a surface protection film may be provided on the side of the protection film 20 of the single-sided protection polarizing film B with the adhesive layer of the present invention. At least a single-sided protective polarizing film with an adhesive layer with a separator (further a surface protective film) can be used as a roll, and it is suitable for outputting a polarizing film with an adhesive layer from the roll and using the separator. The method of transporting parts and pasting them on the surface of the image display panel via the adhesive layer (also known as the "roll-to-panel method", represented by Japanese Patent No. 4406043), can continuously manufacture image display devices.

Fig. 3 is a conceptual diagram comparing the nano-slit a and the through crack b generated in the polarizer. FIG. 3(A) shows the nano slit a generated in the polarizer 10; and FIG. 3(B) shows the through crack b generated in the polarizer 10. As shown in FIG. The nano crevice a is generated by mechanical shock and appears locally in the direction of the absorption axis of the polarizer 10. Although the nano crevice a cannot be confirmed at the first occurrence, it can be exposed to a thermal environment (e.g. 80°C). Or 90%RH at 60°C) to confirm by expanding in the horizontal direction. In addition, we believe that the nano-slit a does not have travel properties extending in the direction of the absorption axis of the polarizer. In addition, we believe that the formation of the aforementioned nano-slit a has nothing to do with the size of the polarizing film. In addition to the single generation of nano-slit a, there are also neighboring ones. On the other hand, the through crack b is caused by thermal shock (for example, thermal shock test). The through cracks have a traveling property extending along the absorption axis direction of the polarizer in which the cracks have been generated. After the through crack b appears, the surrounding stress will be released, so the through cracks will not be adjacent to each other.

<Step (1)> ≪Single-sided protective polarizing film≫ The aforementioned single-sided protective polarizing film is a thin-shaped polarizer with a protective film on one side only. The thickness (total thickness) of the single-sided protective polarizing film is preferably 60 μm or less. Even with such a thin single-sided protective film, a transparent resin layer with a stable film thickness can be formed according to the manufacturing method of the present invention. The thickness of the aforementioned single-sided protective polarizing film may further be 55 μm or less. On the other hand, from the viewpoint of transportability, the thickness of the thin single-sided protective film is preferably 20 μm or more, more preferably 25 μm or more.

"Polarizer" In the present invention, a polarizer with a thickness of 10 μm or less is used. The thickness of the polarizer is preferably 8 μm or less, more preferably 7 μm or less, and more preferably 6 μm or less from the viewpoint of thinning and suppressing the occurrence of through cracks. On the other hand, the thickness of the polarizer is preferably 2 μm or more, more preferably 3 μm or more. Such a thin polarizer has less variation in thickness, excellent visibility (visibility), and low dimensional change, so it has excellent durability against thermal shock.

The polarizer is made of polyvinyl alcohol resin. Examples of polarizers include hydrophilic polymer films such as polyvinyl alcohol-based films, partially formalized polyvinyl alcohol-based films, and ethylene-vinyl acetate copolymer-based partially saponified films that adsorb iodine or dichroic dyes. Chromatic materials and uniaxially stretched, and polyolefin-based alignment films such as dehydrated polyvinyl alcohol or dehydrochloric acid treated polyvinyl chloride. Among them, a polarizer composed of a polyvinyl alcohol-based film and a dichroic substance such as iodine is suitable.

A polarizer made of polyvinyl alcohol-based film dyed with iodine and then uniaxially stretched can be produced, for example, in the following way: the polyvinyl alcohol film is immersed in an aqueous solution of iodine to dye, and then stretched to 3-7 of the original length. Times. It can also be immersed in aqueous solutions such as boric acid or potassium iodide that may contain zinc sulfate, zinc chloride, etc. according to needs. Furthermore, if necessary, the polyvinyl alcohol-based film may be immersed in water for washing before dyeing. By washing the polyvinyl alcohol-based film with water, the dirt and anti-caking agent on the surface of the polyvinyl alcohol-based film can be cleaned. In addition, it also has the effect of swelling the polyvinyl alcohol-based film to prevent uneven dyeing and other defects. The extension can be performed after dyeing with iodine, or it can be extended while dyeing, or it can be dyed with iodine after extension. It can also be extended in aqueous solutions such as boric acid or potassium iodide or in a water bath.

In terms of extension stability or optical durability, the polarizing member preferably contains boric acid. In addition, the content of boric acid contained in the polarizer is preferably 20% by weight or less, more preferably 18% by weight or less, and more preferably 16% by weight relative to the total amount of the polarizer, from the viewpoints of suppressing the occurrence of through cracks and suppressing expansion. %the following. On the other hand, from the viewpoint of the extension stability or optical durability of the polarizer, the boric acid content relative to the total amount of the polarizer is preferably 10% by weight or more, and more preferably 12% by weight or more.

As a thin polarizer, representative examples include Japanese Patent No. 4751486, Japanese Patent No. 4751481, Japanese Patent No. 4815544, Japanese Patent No. 5048120, International Publication No. 2014/077599, International Publication The thin polarizer described in the manual No. 2014/077636, etc., or the thin polarizer obtained by the manufacturing method described in the same.

The aforementioned polarizer is structured such that its optical characteristics expressed by monomer transmittance T and polarization degree P satisfy the conditions of the following formula: P>-(10 ^0.929T-42.4 -1)×100 (but T<42.3); Or P≧99.9 (but T≧42.3). A polarizer configured to satisfy the aforementioned conditions will undoubtedly have the performance required for a liquid crystal television display using a large display element. Specifically, the contrast ratio is 1000:1 or more and the maximum brightness is 500 cd/m ² or more. For other uses, for example, it can be attached to the viewing side of an organic EL display device.

As the aforementioned thin polarizer, the manufacturing method including the stretching step and the dyeing step in the state of a layered body is suitable for high-magnification stretching and improved polarization performance, such as the specification of Japanese Patent No. 4751486 and Japanese Patent As described in the specification No. 4751481 and the specification No. 4815544 of Japanese Patent No. 4815544, the preparation method including the step of extending in an aqueous solution of boric acid is particularly preferably obtained by the specification of the specification of Japanese Patent No. 4751481 and the specification of Japanese Patent No. 4815544. Obtained from the manufacturing method of performing auxiliary aerial stretching step before stretching in aqueous solution. These thin polarizing films can be obtained by a manufacturing method including a step of extending a polyvinyl alcohol-based resin (hereinafter also referred to as a PVA-based resin) layer and a resin substrate for stretching in the state of a laminate and a dyeing step. According to this manufacturing method, even if the PVA-based resin layer is thin, it can be stretched without failures such as breakage due to stretching by being supported by the stretching resin base material.

"Protective Film" The material constituting the above-mentioned protective film is preferably one that is excellent in transparency, mechanical strength, thermal stability, moisture barrier properties, and isotropy. Examples include: polyester-based polymers such as polyethylene terephthalate and polyethylene naphthalate; cellulose-based polymers such as cellulose diacetate and cellulose triacetate; polymethyl methacrylate, etc. Acrylic polymers; styrene polymers such as polystyrene and acrylonitrile-styrene copolymer (AS resin); and polycarbonate polymers. In addition, the following polymers can also be cited as examples of polymers forming the above-mentioned protective film: polyethylene, polypropylene, polyolefins having cyclic or even norbornene structures, such as polyolefin polymerization of ethylene-propylene copolymers Compounds, chlorinated vinyl polymers, amide-based polymers such as nylon and aromatic polyamides, imine-based polymers, turbid polymers, polyether-based polymers, polyether ether ketone-based polymers, Polyphenylene sulfide polymer, vinyl alcohol polymer, chlorinated vinylidene polymer, vinyl butyral polymer, aryl ester polymer, polyoxymethylene polymer, epoxy polymer or the above-mentioned polymerization Blends of materials, etc. The protective films are usually attached to the polarizer via an adhesive layer.

In addition, the protective film may contain one or more arbitrary appropriate additives. Examples of additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, release agents, coloring inhibitors, flame retardants, nucleating agents, antistatic agents, pigments, colorants, and the like. The content of the above-mentioned thermoplastic resin in the protective film is preferably 50-100% by mass, more preferably 50-99% by mass, more preferably 60-98% by mass, and particularly preferably 70-97% by mass. When the content of the above-mentioned thermoplastic resin in the protective film is 50% by mass or less, there may be situations where the high transparency originally possessed by the thermoplastic resin cannot be fully exhibited.

The aforementioned protective film may also use a retardation film, a brightness enhancement film, a diffusion film, and the like. Examples of the retardation film include those having a frontal retardation of 40 nm or more and/or a thickness direction retardation of 80 nm or more. The frontal phase difference is usually controlled in the range of 40~200nm, and the thickness direction phase difference is usually controlled in the range of 80~300nm. When a retardation film is used as a protective film, since the retardation film also functions as a polarizer protective film, thickness reduction can be achieved.

Examples of the retardation film include birefringent films obtained by uniaxially or biaxially stretching a thermoplastic resin film. The above-mentioned stretching temperature, stretching ratio, etc. can be appropriately set according to the retardation value, film material and thickness.

The thickness of the aforementioned protective film can be appropriately set, but in general, from the viewpoints of workability such as strength and handleability, and thin layer properties, it is preferably 2 to 200 μm, and more preferably 3 to 100 μm. Especially when the thickness (total thickness) of the single-sided protective polarizing film is adjusted to 60μm or less, the thickness of the protective film (when the film is formed in advance) is preferably less than 15-60μm in terms of transportability. 20~55μm is better. On the other hand, the thickness of the protective film (when formed by coating and hardening) is preferably 3 to 50 μm in terms of transportability, and more preferably 5 to 40 μm. The aforementioned protective film may use multiple sheets or multiple layers.

Functional layers such as hard coating, anti-reflection layer, anti-adhesion layer, diffusion layer and anti-glare layer can be provided on the surface of the aforementioned protective film that is not bonded to the polarizer. In addition, the above-mentioned functional layers such as the hard layer, the anti-reflection layer, the anti-adhesion layer, the diffusion layer, and the anti-glare layer may not only be provided on the protective film itself, but may also be provided separately from the protective film and be another entity.

<Intermediate layer> The protective film and the polarizer described above can be laminated via an intermediary layer such as an adhesive layer, an adhesive layer, and a primer. At this time, it is ideal to use an interposer to laminate the two without air gaps. Furthermore, the interposer between the polarizer 1 and the protective film 2 is not shown in FIG. 1.

The adhesive layer is formed by the adhesive. The type of adhesive is not particularly limited, and various types can be used. The aforementioned adhesive layer is not particularly limited as long as it is optically transparent, and various forms such as water-based, solvent-based, hot-melt adhesive-based, active energy ray hardening type, etc. can be used as the adhesive. However, water-based adhesives are ideal. Agent or active energy ray hardening adhesive.

Examples of water-based adhesives include isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, and water-based polyesters. The water-based adhesive is usually used in the form of an adhesive composed of an aqueous solution, and usually contains 0.5 to 60% by weight of solid content.

The active energy ray hardening type adhesive is an adhesive that is hardened with active energy rays such as electron beams and ultraviolet rays (radical hardening type, cation hardening type). For example, electron beam hardening type and ultraviolet hardening type can be used. As the active energy ray curable adhesive agent, for example, a light radical curable adhesive agent can be used. When the photoradical curable active energy ray curable adhesive is used as the ultraviolet curable adhesive, the adhesive contains a radical polymerizable compound and a photopolymerization initiator.

The coating method of the adhesive is appropriately selected according to the viscosity and target thickness of the adhesive. Examples of coating methods include: reverse coater, gravure coater (direct, reverse or offset), bar reversal coater, roll coater, mold coater, bar coater, bar Type coating machine, etc. In addition, a dipping method or the like can be suitably used for coating.

In addition, when the aforementioned adhesive is applied using a water-based adhesive, etc., it is preferable to perform the adhesive layer finally formed with a thickness of 30 to 300 nm. The thickness of the aforementioned adhesive layer is more preferably 60 to 150 nm. On the other hand, when an active energy ray-curable adhesive is used, it is preferable to carry out so that the thickness of the adhesive layer is 0.2 to 20 μm.

In addition, when the polarizer and the protective film are laminated, an easy-to-bond layer can be provided between the protective film and the adhesive layer. The easy bonding layer, for example, can be formed by various resins having the following skeletons: polyester skeleton, polyether skeleton, polycarbonate skeleton, polyurethane skeleton, polysiloxane, polyamide skeleton, polyamide Imine skeleton, polyvinyl alcohol skeleton, etc. These polymer resins can be used individually by 1 type or in combination of 2 or more types. In addition, other additives may be added in the formation of the easy-to-bond layer. Specifically, stabilizers such as adhesion imparting agents, ultraviolet absorbers, antioxidants, heat-resistant stabilizers, and the like can be further used.

The easy-adhesive layer is usually set on the protective film in advance, and the easy-adhesive layer side of the protective film and the polarizer are laminated with the adhesive layer. The formation of the easy-adhesive layer is carried out by coating the easy-adhesive layer forming material on the protective film by a conventional technique and drying. The easy-adhesive layer forming material is usually prepared as a solution, which is diluted to an appropriate concentration in consideration of the thickness after drying, the smoothness of the coating, and the like. The thickness of the easy-adhesive layer after drying is preferably 0.01-5 μm, more preferably 0.02-2 μm, and more preferably 0.05-1 μm. In addition, the easy-adhesive layer can be provided with multiple layers, but in this case, it is still preferable to keep the total thickness of the easy-adhesive layer within the above range.

The adhesive layer is formed of an adhesive. Various adhesives can be used for the adhesive, such as rubber adhesives, acrylic adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinylpyrrole Pyridone-based adhesives, polyacrylamide-based adhesives, cellulose-based adhesives, etc. The adhesive base polymer can be selected according to the types of the aforementioned adhesives. Among the aforementioned adhesives, it is preferable to use an acrylic adhesive in terms of excellent optical transparency, exhibiting suitable adhesive properties such as wettability, cohesiveness, and adhesiveness, and excellent weather resistance and heat resistance.

The primer layer (primer layer) is formed to improve the adhesion between the polarizer and the protective film. The material constituting the primer layer is not particularly limited as long as it exhibits a certain degree of strong adhesion to both the base film and the polyvinyl alcohol-based resin layer. For example, a thermoplastic resin excellent in transparency, thermal stability, extensibility, etc. can be used. Examples of thermoplastic resins include acrylic resins, polyolefin resins, polyester resins, polyvinyl alcohol resins, or mixtures thereof.

<<Coating Liquid>> The coating liquid contains a resin component or a curable component that can constitute a resin layer. This coating liquid is used to form a transparent resin layer.

In addition, the form of the coating liquid as the aforementioned coating liquid is not particularly limited as long as it is liquid, and it may be any one of an aqueous system, an aqueous dispersion system, a solvent system, and a solventless system.

Among the aforementioned coating liquids, a low-viscosity coating liquid tends to penetrate the damaged portion of the polarizer, which is advantageous. The aforementioned viscosity measured at 25°C should be below 2000mPa∙s, more preferably below 1000mPa∙s, more preferably below 500mPa∙s, and even more preferably below 100mPa∙s.

The coating of the single-sided protective polarizing film (polarizer side) with the aforementioned coating solution is preferably carried out in such a way that the thickness of the transparent resin layer formed after step (2) is 0.2 μm or more. The thickness of the aforementioned transparent resin layer is preferably 0.5 μm or more, more preferably 0.7 μm or more. On the other hand, if the thickness of the transparent resin layer becomes too thick, the optical reliability and water resistance will decrease. Therefore, the thickness of the transparent resin layer is preferably 3 μm or less, more preferably less than 3 μm, and more preferably 2 μm or less.

The material for forming the transparent resin layer may include, for example, polyester resins, polyether resins, polycarbonate resins, polyurethane resins, silicone resins, polyamide resins, and polyimide resins. Resin, PVA-based resin, acrylic resin, epoxy-based resin, isocyanate-based resin, etc. These resin materials can be used alone or in combination of two or more, among which are selected from the group consisting of polyurethane resins, PVA resins, acrylic resins, and epoxy resins. One or more kinds of resins are preferred, and PVA-based resins and acrylic resins are preferred.

The aforementioned coating liquid is preferably a coating liquid containing a resin component that has been dissolved or dispersed in water. The resin component that has been dissolved or dispersed in water refers to a resin that has been dissolved in water at room temperature (25°C), and a water-soluble resin is dissolved in an aqueous solvent. If the coating liquid is an aqueous system or a water dispersion system, it is advantageous because the surface of the polarizer can be swollen to impregnate the coating liquid into the damaged part. That is, if the coating liquid is water-based or water-dispersed, it can partially reduce the orientation of the polyvinyl alcohol molecules around the damaged part that constitutes the polarizer, and at the same time can reduce the boric acid content around the damaged part, so even if the transparent resin layer The thickness is small (for example, less than 3 μm, or even better, less than 2 μm), which can still effectively inhibit the expansion of the damaged area.

Representative examples of resin components that can be dissolved or dispersed in water include, for example, polyvinyl alcohol resins, poly(meth)acrylic acid, polypropylene amides, methylolated melamine resins, methylolated urea resins, and soluble resins. Phenolic phenol resin, polyethylene oxide, carboxymethyl cellulose, etc. These etc. can be used individually or in combination of multiple. The aforementioned resin component preferably uses polyvinyl alcohol-based resin, poly(meth)acrylic acid, and methylolated melamine. From the viewpoint of adhesion to the polyvinyl alcohol-based resin constituting the polarizer, the aforementioned resin component is particularly preferably a polyvinyl alcohol-based resin. The case where polyvinyl alcohol-based resin is used is described below.

The transparent resin layer is preferably formed of a forming material containing a polyvinyl alcohol-based resin. The polyvinyl alcohol-based resin forming the transparent resin layer may be "polyvinyl alcohol-based resin", and it may be the same as or different from the polyvinyl alcohol-based resin contained in the polarizer.

Examples of the polyvinyl alcohol-based resin include polyvinyl alcohol. Polyvinyl alcohol is obtained by saponifying polyvinyl acetate. In addition, polyvinyl alcohol-based resins include, for example, saponified products of copolymers of vinyl acetate and copolymerizable monomers. When the aforementioned copolymerizable monomer is ethylene, an ethylene-vinyl alcohol copolymer is obtained. In addition, the aforementioned copolymerizable monomers include unsaturated carboxylic acids such as maleic acid (anhydride), fumaric acid, crotonic acid, itaconic acid, (meth)acrylic acid, and their esters, ethylene, propylene, etc. -Olefin, (meth)acrylic acid (sodium), sodium sulfonate (monoalkylmalate), sodium disulfonate alkylmalate, N-methylol acrylamide, acrylamide alkyl Sulfonic acid alkali metal salt, N-vinylpyrrolidone, N-vinylpyrrolidone derivatives, etc. These polyvinyl alcohol-based resins may be used singly or in combination of two or more kinds.

The degree of saponification of the aforementioned polyvinyl alcohol resin can be, for example, 95 mol% or more. However, from the viewpoint of satisfying moisture and heat resistance and water resistance, the saponification degree is preferably 99 mol% or more, more preferably 99.7 mol%. Ear% or more. The degree of saponification means the ratio of units that can actually be saponified into vinyl alcohol units among the units that can be converted into vinyl alcohol units by saponification, and the residues are vinyl ester units. The degree of saponification can be determined in accordance with JIS K 6726-1994.

The average degree of polymerization of the aforementioned polyvinyl alcohol-based resin can be, for example, 500 or more, but from the viewpoint of satisfying moisture and heat resistance and water resistance, the average degree of polymerization is preferably 1000 or more, more preferably 1500 or more, and more preferably 2000 the above. The average degree of polymerization of the polyvinyl alcohol-based resin is measured in accordance with JIS-K6726.

In addition, the polyvinyl alcohol-based resin may be a modified polyvinyl alcohol-based resin having a hydrophilic functional group on the side chain of the polyvinyl alcohol or its copolymer. Examples of the aforementioned hydrophilic functional group include an acetylacetoxy group and a carbonyl group. In other respects, modified polyvinyl alcohol obtained by acetalizing, urethane-forming, etherifying, grafting, phosphoricating, etc. of a polyvinyl alcohol-based resin can be used.

The ratio of the polyvinyl alcohol resin in the transparent resin layer or the forming material (solid content) is preferably 80% by weight or more, more preferably 90% by weight or more, and more preferably 95% by weight or more.

The coating liquid is prepared to prepare a solution in which the polyvinyl alcohol-based resin has been dissolved in a solvent. Examples of solvents include water, dimethyl sulfide, dimethylformamide, dimethylacetamide-N-methylpyrrolidone, various glycols, and polyvalent alcohols such as trimethylolpropane. , Ethylenediamine, diethylenetriamine and other amines. These can be used alone or in combination of two or more kinds. Among them, it is preferable to use an aqueous solution using water as a solvent. Although the concentration of the polyvinyl alcohol-based resin in the aforementioned forming material (for example, an aqueous solution) is not particularly limited, it is 0.1 to 15% by weight, preferably 0.5 to 10% by weight in consideration of coating properties and storage stability, etc. %.

In addition, in the aforementioned coating liquid (for example, an aqueous solution), examples of additives include plasticizers and surfactants. Examples of the plasticizer include polyhydric alcohols such as ethylene glycol and glycerol. Examples of the surfactant include nonionic surfactants. In addition, it can also be matched with coupling agents such as silane coupling agent, titanium coupling agent, various adhesive excipients, ultraviolet absorbers, antioxidants, heat-resistant stabilizers, hydrolysis-resistant stabilizers and other stabilizers.

The application of the aforementioned coating liquid is preferably carried out so that the thickness after drying is 0.2 μm or more. The coating operation is not particularly limited, and any appropriate method can be adopted. For example, gravure coating method (direct, reverse or lithography), roll coating method, spin coating method, wire bar coating method, dip coating method, die coating method, curtain coating method, spraying method, doctor blade method can be used Various methods such as coating method (comma blade coating method, etc.).

Next, regarding the formation of the aforementioned transparent resin layer, the situation when a coating liquid containing a curable component that can constitute a resin is used will be described. The curable components can be roughly classified into active energy ray curable types such as electron beam curable type, ultraviolet curable type, and visible light curable type, and heat curable type. Furthermore, ultraviolet curing type and visible light curing type can be divided into radical polymerization curing type and cationic polymerization curing type. In the present invention, the active energy line with a wavelength range of 10 nm to less than 380 nm is recorded as ultraviolet light, and the active energy line with a wavelength range of 380 nm to 800 nm is recorded as visible light. The aforementioned radical polymerization curable type curable component can be used as a thermosetting type curable component.

<<radical polymerization curable forming material>> Examples of the curable component include a radical polymerizable compound. Examples of the radical polymerizable compound include compounds having a carbon-carbon double bond radical polymerizable functional group such as a (meth)acryloyl group and a vinyl group. As these curable components, either a monofunctional radical polymerizable compound or a bifunctional or more polyfunctional radical polymerizable compound can be used. Moreover, these radically polymerizable compounds can be used individually by 1 type or in combination of 2 or more types. As these radically polymerizable compounds, for example, a compound having a (meth)acryloyl group is suitable. In addition, in the present invention, the term “(meth)acryloyl group” means an acryloyl group and/or methacryloyl group, and “(meth)” is synonymous below.

"Monofunctional radical polymerizable compound" The monofunctional radical polymerizable compound includes, for example, a (meth)acrylamide derivative having a (meth)acrylamide group. The (meth)acrylamide derivative is ideal in terms of ensuring adhesion to the polarizer, and in terms of high polymerization speed and excellent productivity. Specific examples of (meth)acrylamide derivatives include N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl N-alkyl (meth)acrylamide, N-isopropyl(meth)acrylamide, N-butyl(meth)acrylamide, N-hexyl(meth)acrylamide, etc. (Meth)acrylamide derivatives; N-hydroxymethyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-hydroxymethyl-N-propane (methyl) N-hydroxyalkyl-containing (meth)acrylamide derivatives such as acrylamide; aminomethyl(meth)acrylamide, aminoethyl(meth)acrylamide, etc., containing N-aminoalkyl (Meth)acrylamide derivatives; N-alkoxy-containing (meth)acrylamide derivatives such as N-methoxymethacrylamide and N-ethoxymethacrylamide; hydrogen N-hydrosulfanyl alkyl-containing (meth)acrylamide derivatives such as thiomethyl(meth)acrylamide, hydrosulfanethyl(meth)acrylamide, and the like. In addition, the nitrogen atom of the (meth)acrylamido group forms a heterocyclic ring-containing (meth)acrylamido derivative, such as N-acryloylmorpholine, N-acryloylpiper Pyridine, N-methacryloylpiperidine, N-acryloylpyrrolidine, etc.

Among the aforementioned (meth)acrylamide derivatives, from the point of view of the adhesion to the polarizing member, it is also preferable to use N-hydroxyalkyl-containing (meth)acrylamide derivatives, especially Preferably, it is N-hydroxyethyl (meth)acrylamide.

In addition, examples of the monofunctional radical polymerizable compound include various (meth)acrylic acid derivatives having a (meth)acryloyloxy group. Specifically, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, 2-methyl-2-nitro Propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, third butyl (meth)acrylate, (meth) ) N-pentyl acrylate, 3-pentyl (meth)acrylate, 3-pentyl (meth)acrylate, 2,2-dimethylbutyl (meth)acrylate, n-hexyl (meth)acrylate , Cetyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 4-methyl-2-propylpentyl (meth)acrylate, (Meth) acrylic acid (carbon number 1-20) alkyl esters such as n-octadecyl (meth)acrylate.

In addition, examples of the aforementioned (meth)acrylic acid derivatives include cycloalkyl (meth)acrylates such as cyclohexyl (meth)acrylate and cyclopentyl (meth)acrylate; benzyl (meth)acrylic acid Aralkyl (meth)acrylates such as esters; 2-isobornyl (meth)acrylate, 2-norbornylmethyl (meth)acrylate, 5-norbornen-2-yl-methyl (Meth) acrylate, 3-methyl-2-norbornyl methyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl oxyethyl (methyl) ) Polycyclic (meth)acrylates such as acrylate and dicyclopentyl (meth)acrylate; 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (methyl) )Acrylate, 2-methoxymethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxy Ethyl (meth)acrylate, alkylphenoxy polyethylene glycol (meth)acrylate, etc., contain alkoxy or phenoxy (meth)acrylates and the like.

In addition, the aforementioned (meth)acrylic acid derivatives may include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2 -Hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (Meth)acrylate, 12-hydroxylauryl (meth)acrylate and other hydroxyalkyl (meth)acrylates or [4-(hydroxymethyl)cyclohexyl]methacrylate, cyclohexanedi Hydroxyl-containing (meth)acrylates such as methanol mono(meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, etc.; Glycidyl (meth)acrylate, 4- Epoxy-containing (meth)acrylates such as hydroxybutyl (meth)acrylate glycidyl ether; 2,2,2-trifluoroethyl (meth)acrylate, 2,2,2- Trifluoroethylethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropentyl (meth)acrylate, heptafluorodecane Halogen-containing (meth)acrylates such as methyl (meth)acrylate and 3-chloro-2-hydroxypropyl (meth)acrylate; Alkyl groups such as dimethylaminoethyl (meth)acrylate Amino alkyl (meth) acrylate; 3-oxopyranyl methyl (meth) acrylate, 3-methyloxopyranyl methyl (meth) acrylate, 3-ethyl oxoporyl methyl (meth) acrylate (Meth) acrylate, 3-butyloxypyrylmethyl (meth)acrylate, 3-hexyloxypyrylmethyl (meth)acrylate, and other oxygen-containing phenyl(meth)acrylates; tetrahydrofuran Meth (meth) acrylate, butyrolactone (meth) acrylate, and other heterocyclic (meth) acrylates, or hydroxytrimethyl acetate neopentyl glycol (meth) acrylic acid adduct, p -Phenylphenol (meth)acrylate and the like.

In addition, the monofunctional radical polymerizable compound includes carboxyl group-containing monomers such as (meth)acrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid. .

、乙烯基吡

、乙烯基吡咯、乙烯基咪唑、乙烯基

唑、乙烯基嗎福啉等具有含氮雜環之乙烯系單體等等。In addition, examples of monofunctional radical polymerizable compounds include internal vinyl monomers such as N-vinylpyrrolidone, N-vinyl-ε-caprolactone, and methyl vinylpyrrolidone. ; Vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiper

Vinylpyridine

, Vinyl pyrrole, vinyl imidazole, vinyl

Ethylene monomers with nitrogen-containing heterocycles such as azole, vinylmorpholine, etc.

In addition, as the monofunctional radical polymerizable compound, a radical polymerizable compound having an active methylene group can be used. The radically polymerizable compound having an active methylene group is a compound having an active double bond group such as a (meth)acryloyl group at the terminal or in the molecule, and having an active methylene group. As the active methylene group, for example, an acetylacetoxy group, an alkoxypropanedioxin group, or a cyanoacetoxy group may be mentioned. The aforementioned active methylene group is preferably acetyl acetyl. For example, specific examples of radically polymerizable compounds having active methylene groups include 2-acetylacetoxyethyl (meth)acrylate, 2-acetylacetoxypropyl (formaldehyde) Acetyl acetoxy alkyl (meth) acrylates such as 2-ethoxy acetoxy-1-methylethyl (meth) acrylate, 2-ethoxy acetoxy oxyalkyl (meth) acrylate; 2-ethoxy propanedioic acid Oxyethyl (meth)acrylate, 2-cyanoacetoxyethyl (meth)acrylate, N-(2-cyanoacetoxyethyl)acrylamide, N-( 2-Propylacetoxybutyl)acrylamide, N-(4-acetylacetoxymethylbenzyl)acrylamide, N-(2-acetylacetoxyaminoethyl ) Acrylamide and so on. The radically polymerizable compound with active methylene group is preferably acetoxyalkyl (meth)acrylate.

"Multifunctional Radical Polymerizable Compound" In addition, examples of the bifunctional or higher multifunctional radical polymerizable compound include tripropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, and 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 di(meth)acrylate, bisphenol A ethylene oxide adduct di(meth)acrylate, bisphenol A propylene oxide adduct di(methyl) )Acrylate, bisphenol A diglycidyl ether di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, cyclic trihydroxy Methylpropane methylal (meth)acrylate, diethylene 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, EO modified diglycerol tetra (meth) acrylate Etc. (meth)acrylic acid and polyol esters, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]茀. Specific examples include ARONIX M-220, M-306 (manufactured by Toagosei Co., Ltd.), LIGHT ACRYLATE 1,9ND-A (manufactured by Kyoeisha Chemical Co., Ltd.), LIGHT ACRYLATE DGE-4A (manufactured by Kyoeisha Chemical Co., Ltd.), LIGHT ACRYLATE DCP-A (manufactured by Kyoeisha Chemical Co., Ltd.), SR-531 (manufactured by Sartomer Corporation), CD-536 (manufactured by Sartomer Corporation), etc. Moreover, various epoxy (meth)acrylates, urethane (meth)acrylates, polyester (meth)acrylates, or various (meth)acrylate monomers, etc. can be mentioned as needed.

From the viewpoint of compatibility with the polarizer and optical durability, the radical polymerizable compound is preferably used in combination with a monofunctional radical polymerizable compound and a polyfunctional radical polymerizable compound. Generally speaking, it is suitable to use together in the following ratio: relative to 100% by weight of the radically polymerizable compound, 3 to 80% by weight of the monofunctional radically polymerizable compound and 20 to 97% by weight of the multifunctional radically polymerizable compound are used in combination.

"The state of the free radical polymerization hardening forming material" The radical polymerization hardening forming material can be used as an active energy ray hardening type or a thermosetting type forming material. When the active energy ray uses an electron beam or the like, the active energy ray hardening forming material does not need to contain a photopolymerization initiator; however, when the active energy ray uses ultraviolet or visible light, it is preferable to contain a photopolymerization initiator. On the other hand, when the aforementioned curable component is used as a thermosetting component, the forming material preferably contains a thermal polymerization initiator.

(thioxanthone)、2-氯-9-氧硫𠮿

、2-甲硫基𠮿酮、2,4-二甲硫基𠮿酮、異丙基-9-氧硫𠮿

、2,4-二氯-9-氧硫𠮿

、2,4-二乙基-9-氧硫𠮿

、2,4-二異丙基-9-氧硫𠮿

、十二基-9-氧硫𠮿

等9-氧硫𠮿

系化合物；樟腦醌；鹵化酮；醯基氧化膦；醯基膦酸酯等。"Photoinitiator" When a radical polymerizable compound is used, the photoinitiator can be appropriately selected in accordance with active energy rays. In the case of curing by ultraviolet or visible light, a photopolymerization initiator that is cleaved by ultraviolet or visible light is used. Examples of the aforementioned photopolymerization initiator include benzil, diphenyl ketone, benzyl benzoic acid, and 3,3'-dimethyl-4-methoxydiphenyl ketone. And other benzophenone compounds; 4-(2-hydroxyethoxy) phenyl(2-hydroxy-2-propyl) ketone, α-hydroxy-α,α'-dimethylacetophenone, 2- Aromatic ketone compounds such as methyl-2-hydroxypropiophenone and α-hydroxycyclohexylphenylketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2 -Diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholine-1-acetone and other acetophenone compounds; benzoin methyl ether , Benzoin ether, benzoin isopropyl ether, benzoin butyl ether, anisole methyl ether and other benzoin ether compounds; benzyl dimethyl ketal and other aromatic ketal compounds; 2-naphthalene Aromatic sulfonyl chloride compounds such as sulfonyl chloride; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime; 9-oxysulfur 𠮿

(thioxanthone), 2-chloro-9-oxysulfur𠮿

, 2-methylthioketone, 2,4-dimethylthioketone, isopropyl-9-oxythioketone

, 2,4-Dichloro-9-oxysulfur 𠮿

, 2,4-Diethyl-9-oxysulfur

, 2,4-Diisopropyl-9-oxysulfur 𠮿

, Dodecyl-9-oxysulfur 𠮿

Waiting for 9-oxysulfur 𠮿

Series compounds; camphorquinone; halogenated ketones; acyl phosphine oxide; acyl phosphonate and the like.

The blending amount of the aforementioned photopolymerization initiator is 20 parts by weight or less with respect to 100 parts by weight of the total amount of the curable component (radical polymerizable compound). The blending amount of the photopolymerization initiator is preferably 0.01-20 parts by weight, more preferably 0.05-10 parts by weight, and more preferably 0.1-5 parts by weight.

In addition, when using a visible light curable type containing a radical polymerizable compound as the curable component, it is particularly suitable to use a photopolymerization initiator that has high sensitivity to light of 380 nm or more. The photopolymerization initiator with high sensitivity to light above 380 nm will be described in detail later.

(式中，R¹ 及R² 顯示-H、-CH₂ CH₃ 、-iPr或Cl，R¹ 及R² 可為相同或相異)。在使用通式(1)所示化合物時，密著性會優於單獨使用對380nm以上光線有高感度之光聚合引發劑。通式(1)所示化合物當中，尤佳的是R¹ 及R² 為-CH₂ CH₃ 時的二乙基-9-氧硫𠮿

。相對於100重量份之硬化性成分的總量，該形成材中一般式(1)所示化合物之組成比率以0.1~5重量份為佳，0.5~4重量份較佳，而0.9~3重量份更佳。As the aforementioned photopolymerization initiator, it is preferable to use the compound represented by the following general formula (1) alone or in combination with the compound represented by the general formula (1) and the photopolymerization initiator with high sensitivity to light of 380 nm or more described later. [Chemical formula 1]

(In the formula, R ¹ and R ² show -H, -CH ₂ CH ₃ , -iPr or Cl, and R ¹ and R ² may be the same or different). When the compound represented by the general formula (1) is used, the adhesion is better than that of using a photopolymerization initiator that has high sensitivity to light above 380 nm alone. Among the compounds represented by the general formula (1), particularly preferred is diethyl-9-oxysulfur when ^{R 1} and R ² are -CH ₂ CH ₃

. Relative to 100 parts by weight of the total amount of curable components, the composition ratio of the compound represented by the general formula (1) in the formed material is preferably 0.1 to 5 parts by weight, preferably 0.5 to 4 parts by weight, and 0.9 to 3 parts by weight Better servings.

It is also advisable to add polymerization initiation aids as needed. The polymerization initiation aids include triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylamine benzoic acid, methyl 4-dimethylamine benzoate, and ethyl 4-dimethylamine benzoate. Ester, isoamyl 4-dimethylaminobenzoate, etc., and ethyl 4-dimethylaminobenzoate is particularly preferred. When the polymerization initiation aid is used, its addition amount is usually 0-5 parts by weight relative to 100 parts by weight of the total amount of curable components, preferably 0-4 parts by weight, and most preferably 0-3 parts by weight.

In addition, well-known photopolymerization initiators can be used in combination as needed. The protective film with UV absorption energy will not penetrate light below 380nm. Therefore, it is better to use a photopolymerization initiator with high sensitivity to light above 380nm in terms of photopolymerization initiator. Specifically, examples include 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, 2-benzyl-2-dimethylamino-1-(4 -Morpholinophenyl)-1-butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl) Phenyl)-1-butanone, 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzyl)-phenyl Phosphine oxide, bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium and the like.

(式中，R³ 、R⁴ 及R⁵ 表示-H、-CH₃ 、-CH₂ CH₃ 、-iPr或Cl，且R³ 、R⁴ 及R⁵ 可相同或相異)。通式(2)所示化合物可適合使用亦有市售品的2-甲基-1-(4-甲硫基苯基)-2-嗎福啉-1-丙酮(商品名：IRGACURE907，製造者：BASF)。除此之外，2-苄基-2-二甲胺基-1-(4-嗎福啉苯基)- 1-丁酮(商品名：IRGACURE369，製造者：BASF)、2-(二甲胺基)-2-[(4-甲基苯基)甲基]-1-[4-(4-嗎福啉基)苯基]-1-丁酮(商品名：IRGACURE379，製造者：BASF)由於感度高，因此較為理想。In particular, as the photopolymerization initiator, in addition to the photopolymerization initiator of the general formula (1), it is preferable to further use a compound represented by the following general formula (2): [Chemical formula 2]

(In the formula, R ³ , R ⁴ and R ⁵ represent -H, -CH ₃ , -CH ₂ CH ₃ , -iPr or Cl, and R ³ , R ⁴ and R ⁵ may be the same or different). The compound represented by the general formula (2) can be suitably used, which is also commercially available 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone (trade name: IRGACURE907, manufactured by Author: BASF). In addition, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone (trade name: IRGACURE369, manufacturer: BASF), 2-(dimethylamino) Amino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (trade name: IRGACURE379, manufacturer: BASF ) It is ideal because of its high sensitivity.

"Thermal polymerization initiator" The thermal polymerization initiator is preferably one that does not use thermal cracking to initiate polymerization. For example, the thermal polymerization initiator is preferably one with a 10-hour half-life temperature of 65°C or higher, and more preferably 75 to 90°C. In addition, the so-called half-life is an index indicating the decomposition rate of the polymerization initiator, and it refers to the time until the residual amount of the polymerization initiator becomes half. The decomposition temperature used to reach the half-life at any time or the half-life time at any temperature is disclosed in the manufacturer’s catalog, for example, in the "Organic Peroxide Catalogue 9th Edition (2003) of Japan Oils and Fats Co., Ltd. May)" and so on.

Examples of thermal polymerization initiators include laurel peroxide (10-hour half-life temperature: 64°C), benzyl peroxide (10-hour half-life temperature: 73°C), 1,1-bis(tertiarybutylperoxy)- 3,3,5-Trimethylcyclohexane (10-hour half-life temperature: 90℃), bis(2-ethylhexyl) peroxydicarbonate (10-hour half-life temperature: 49℃), bis(4-tri Grade butyl cyclohexyl) peroxydicarbonate, di-secondary butyl peroxydicarbonate (10-hour half-life temperature: 51℃), tertiary butyl peroxyneodecanoate (10-hour half-life temperature: 48 ℃), tertiary hexyl peroxy trimethyl acetate, tertiary butyl peroxy trimethyl acetate, dilaurel peroxide (10 hours half-life temperature: 64 ℃), di-n-octyl peroxide Oxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (10-hour half-life temperature: 66℃), bis(4-methylbenzyl) peroxide, Dibenzyl peroxide (10-hour half-life temperature: 73°C), tertiary butylperoxy isobutyl ester (10-hour half-life temperature: 81°C), 1,1-bis(tertiary hexylperoxy)cyclohexane Organic peroxides such as alkanes.

In addition, the thermal polymerization initiator may include, for example, 2,2'-azobisisobutyronitrile (10-hour half-life temperature: 67°C), 2,2'-azobis(2-methylbutyronitrile) (10 hours) Half-life temperature: 67°C), 1,1-azobis-cyclohexane-1-carbonitrile (10-hour half-life temperature: 87°C) and other azo compounds.

The blending amount of the thermal polymerization initiator is 0.01-20 parts by weight relative to 100 parts by weight of the total amount of the curable component (radical polymerizable compound). The blending amount of the thermal polymerization initiator is more preferably 0.05-10 parts by weight, and further 0.1-3 parts by weight.

"Cation polymerization hardening forming material" The hardening component of the cation polymerization hardening forming material can be, for example, a compound having an epoxy group or an oxetanyl group. The compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various generally known curable epoxy compounds can be used. Preferred epoxy compounds include, for example, compounds having at least two epoxy groups and at least one aromatic ring in the molecule (aromatic epoxy compounds), or compounds having at least two epoxy groups in the molecule, and at least A compound formed between two adjacent carbon atoms constituting an alicyclic ring (alicyclic epoxy compound), etc.

"Photocationic Polymerization Initiator" The curable component of the cationic polymerization curable forming material contains the epoxy compound and oxygen compound described above. Since these are cured by cationic polymerization, a photocationic polymerization initiator is blended. The photocationic polymerization initiator is irradiated with active energy rays such as visible rays, ultraviolet rays, X-rays, electron beams, etc., to generate cationic substances or Lewis acid, and initiate the polymerization reaction of epoxy groups and oxycyclobutyl groups.

The coating method of the hardening profile (coating liquid) is appropriately selected according to the viscosity and target thickness of the hardening profile. Examples of coating methods include, for example, reverse coaters, gravure coaters (direct, reverse or offset), rod reverse coaters, roll coaters, mold coaters, bar coaters, doctor blades Bar coater, etc. In addition, a dipping method or the like can be suitably used for coating.

<Step (2)> In step (2), the step (2) of "curing or hardening the coating liquid after the coating step (1)" is performed to form a transparent resin layer.

In the formation of the aforementioned transparent resin layer, after coating the coating liquid containing the aforementioned resin component, the resin component is cured according to the type. The coating liquid containing the aforementioned resin component is a solution in which the aforementioned resin component is dissolved in a solvent, or a dispersion liquid in which the aforementioned resin component is dispersed in a solvent. For example, it can be used as an aqueous solution, an aqueous dispersion dispersion, or a solvent solution To use. The aforementioned curing means that the resin layer is formed by removing the solvent from the aforementioned coating liquid. For example, when the resin component is a polyvinyl alcohol-based resin, the coating liquid can be used as an aqueous solution and cured by heating or the like. In addition, when the aforementioned resin component is a water-soluble acrylic type, curing can be performed in the same manner.

The drying temperature is usually 60~200℃, more preferably 70~120℃. The drying time is preferably 10 to 1800 seconds, more preferably 20 to 600 seconds.

On the other hand, in the formation of the aforementioned transparent resin layer, after applying a coating solution containing a curable component that can constitute the resin, the curing operation that can make the curable component form a resin is performed according to the type of the curable component . The coating liquid containing the curable component that can constitute the resin, if the curable component is in the form of a coating liquid, a solvent-free system can be used. In addition, the aforementioned coating liquid may be a solution in which the aforementioned curable component has been dissolved in a solvent. Furthermore, when the aforementioned curable component is in the form of a coating liquid, it can also be used as a solution. The aforementioned solvents can be appropriately selected according to the curable ingredients used. For example, when an acrylic monomer that can form an acrylic resin is used as the curable component, or an epoxy monomer that can form an epoxy resin is used as the curable component, the The coating liquid is subjected to curing operations such as irradiation with active energy rays (ultraviolet rays).

Regarding the formation of a transparent resin layer using the aforementioned hardening forming material (coating liquid), it is performed by coating the hardening forming material on the surface of the polarizer and then curing it.

The polarizer may also be subjected to surface modification treatment before coating the above-mentioned hardened profile forming material. Specific treatment methods include, for example, corona treatment, plasma treatment, and saponification treatment.

<Hardening of forming material> The above-mentioned hardened forming material can be used as an active energy ray-curable forming material or a thermosetting forming material. Among active energy ray hardening forming materials, it can be used in electron beam hardening type, ultraviolet hardening type, and visible light hardening type. From the viewpoint of productivity, the state of the aforementioned hardening profile is that the active energy ray hardening profile is better than the thermosetting profile; furthermore, from the viewpoint of productivity, it is better to use visible light The wire-curing molding material is an active energy ray-curing molding material.

"Active energy ray hardening type" For the active energy ray hardening forming material, the active energy ray hardening forming material is coated on the polarizer and then irradiated with active energy rays (electron beam, ultraviolet light, visible light, etc.), and The active energy ray-curable forming material is cured to form a transparent resin layer. The irradiation direction of active energy rays (electron beam, ultraviolet rays, visible rays, etc.) can be irradiated from any appropriate direction. It is better to irradiate from the side of the transparent resin layer.

"Electron beam hardening type" In the electron beam hardening type, the irradiation conditions of the electron beam may be any conditions that can harden the active energy ray hardening forming material, and any appropriate conditions can be adopted. For example, when irradiating an electron beam, the accelerating voltage should be 5kV~300kV, and more preferably 10kV~250kV. When the accelerating voltage is less than 5kV, the electron beam cannot reach the deepest part of the transparent resin layer and may become insufficiently hardened; and if the accelerating voltage is greater than 300kV, the penetration force through the sample will be too strong and it will affect the protective film or polarizer. The danger of causing damage. The amount of irradiation is 5-100 kGy, preferably 10-75 kGy. When the amount of irradiation is less than 5kGy, the adhesive will not harden enough; when it exceeds 100kGy, it will cause damage to the protective film or polarizer, resulting in reduced mechanical strength or yellowing, and the predetermined optical properties cannot be obtained.

Electron beam irradiation is usually carried out in an inert gas, if necessary, it can also be carried out in the atmosphere or under the condition of introducing a little oxygen.

"Ultraviolet Curing Type, Visible Light Curing Type" In the manufacturing method of the polarizing film of the present invention, the active energy line should preferably contain the visible light in the wavelength range of 380nm~450nm, especially the irradiation amount of the visible light in the wavelength range of 380nm~450nm The most active energy line. As the active energy ray of the present invention, it is suitable to be a metal halide lamp enclosed with gallium and an LED light source with a wavelength range of 380~440nm. Alternatively, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, incandescent bulbs, xenon lamps, halogen lamps, carbon arc lamps, metal halide lamps, fluorescent lamps, tungsten lamps, gallium lamps, excimer lasers or Sunlight and other light sources including ultraviolet and visible light can also be used by shielding ultraviolet light with a wavelength shorter than 380nm with a band-pass filter.

"Thermosetting type" On the other hand, the thermosetting forming material is heated by a thermal polymerization initiator to initiate polymerization to form a hardened layer. The heating temperature can be set according to the thermal polymerization initiator, but is 60 to 200°C, and preferably 80 to 150°C.

<Step (3)> Next, step (3) is carried out, without winding the single-sided protective polarizing film with a transparent resin layer obtained in step (2) into a roll, an adhesive layer is formed on the transparent resin layer, and Polarizing film with adhesive layer can be manufactured. Separator can be provided on the adhesive layer of the polarizing film to which the adhesive layer is attached.

<Adhesive layer> For the formation of the adhesive layer, an appropriate adhesive can be used, and there is no particular restriction on the type. Examples of adhesives include rubber-based adhesives, acrylic-based adhesives, silicone-based adhesives, urethane-based adhesives, vinyl alkyl ether-based adhesives, polyvinyl alcohol-based adhesives, and polysiloxane adhesives. Vinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, cellulose-based adhesives, etc.

Among these adhesives, it is suitable to use those having good optical transparency, exhibiting adhesive properties such as proper wettability, cohesiveness, and adhesiveness, and excellent weather resistance and heat resistance. For those exhibiting such characteristics, it is better to use an acrylic adhesive.

As for the method of forming the adhesive layer, it can be produced by, for example, the following method: apply the aforementioned adhesive to a peel-off part, etc., dry and remove the polymerization solvent, etc. to form the adhesive layer, and then transfer The method of polarizing member; or the method of coating the aforementioned adhesive on the polarizing member, drying and removing the polymerization solvent, etc., to form an adhesive layer on the polarizing member, etc. In addition, when applying the adhesive, one or more solvents other than the polymerization solvent may be appropriately added.

It is advisable to use a silicone release liner as a separation part after peeling treatment. In the step of coating and drying the adhesive of the present invention on such a lining material to form an adhesive layer, a suitable and appropriate method can be used as a method for drying the adhesive according to the purpose. It is preferable to use a method of overheating and drying the above-mentioned coating film. The heating and drying temperature is preferably 40°C to 200°C, more preferably 50°C to 180°C, and particularly preferably 70°C to 170°C. By setting the heating temperature to the above range, an adhesive 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.

Various methods can be used for forming the adhesive layer. Specifically, for example, roller coating method, contact sizing roller coating method, gravure coating method, reverse coating method, roller brush method, spraying method, dip roller coating method, bar coating method, knife coating method, gas Knife coating method, curtain coating method, lip die coating method, extrusion coating method using mold coater, etc.

The thickness of the adhesive layer is not particularly limited, and is, for example, about 1 to 100 μm. It is preferably 2 to 50 μm, preferably 2 to 40 μm, and more preferably 5 to 35 μm.

When the aforementioned adhesive layer is exposed, it can also be protected by a stripped sheet (separator) before actual use.

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 sheet materials such as, metal foil, and laminates thereof, etc., but in terms of excellent surface smoothness, plastic film is suitable.

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

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

<Surface protection film> A surface protection film can be provided on the polarizing film of the present invention (including single-sided protection polarizing film and polarizing film with adhesive layer). The surface protection film usually has a substrate film and an adhesive layer, and protects the polarizer through the adhesive layer.

For the base film of the surface protection film, from the viewpoints of inspection and management, a thin film material with isotropic or nearly isotropic properties is selected. The film material may include, for example, polyester resins such as polyethylene terephthalate films, cellulose resins, acetate resins, polyether turpentine resins, polycarbonate resins, polyamide resins, etc. Polyimide resins, polyolefin resins, and acrylic resins are transparent polymers. Among them, polyester-based resins are suitable. The base film can also be a laminate of one or more than two types of film materials, and in addition, an extension of the aforementioned film can also be used. The thickness of the substrate film is usually 500 μm or less, preferably 10 to 200 μm.

It is possible to appropriately select and use (meth)acrylic polymers, silicone polymers, polyesters, polyurethanes, polyamides, polyethers, fluorine-based and rubber-based polymers as the base for polymerization It is used as an adhesive to form the adhesive layer of the surface protection film. From the viewpoints of transparency, weather resistance, heat resistance, etc., an acrylic adhesive having an acrylic polymer as a base polymer is suitable. The thickness of the adhesive layer (dry film thickness) is determined according to the required adhesive force. It is usually about 1-100μm, and preferably 5-50μm.

In addition, in the surface protection film, a release treatment layer can be provided on the surface of the base film opposite to the surface where the adhesive layer is provided, using low-adhesion materials such as silicone treatment, long-chain alkyl treatment, fluorine treatment, etc.

<Other optical layers> The one-sided protective polarizing film with an adhesive layer of the present invention can be used as an optical film laminated with other optical layers in actual use. The optical layer is not particularly limited, and one layer or two or more layers such as reflectors and semi-transmissive plates, retardation plates (including 1/2 and 1/4 wavelength plates), viewing angle compensation films, etc. can be used to form Optical layer for liquid crystal display devices, etc. Particularly preferred is a reflective polarizing film or a semi-transmissive polarizing film formed by laminating a reflective plate or a semi-transmissive reflective plate on the single-sided protective polarizing film with an adhesive layer of the present invention, and then laminating on the polarizing film An elliptical polarizing film or a circular polarizing film made of a phase difference plate, a wide viewing angle polarizing film made by laminating a viewing angle compensation film on a polarizing film, or a polarizing film made by laminating a brightness enhancement film on a polarizing film.

The optical film formed by laminating the above-mentioned optical layer on the single-sided protective polarizing film with the adhesive layer of the present invention can also be formed in a sequential manner during the manufacturing process of a liquid crystal display device, etc., but it is laminated in advance. Optical films have advantages in terms of quality stability and assembly operations, and have the advantage of improving the manufacturing process of liquid crystal display devices. It can be laminated using an appropriate bonding means such as an adhesive layer. When the single-sided protective polarizing film or other optical films with the adhesive layer attached, the optical axis of the polarizing film or other optical films can be arranged at an appropriate angle in accordance with the intended retardation characteristics.

The single-sided protective polarizing film or optical film with an adhesive layer of the present invention can be suitably used for the formation of various devices such as liquid crystal display devices. The formation of the liquid crystal display device can be performed according to conventional knowledge. That is, the liquid crystal display device is generally formed by appropriately assembling structural parts such as a liquid crystal element, a single-sided polarizing film or optical film with an adhesive layer, and an illumination system as needed, and installing a driving circuit. In the present invention, It is not particularly limited except for the use of the single-sided protective polarizing film or optical film with the adhesive layer of the present invention from the present invention, and it may be based on conventional knowledge. As for the liquid crystal cell, any type, such as IPS type, VA type, etc., can also be used, but the IPS type is particularly suitable.

It can be formed on one side or both sides of a liquid crystal element with a single-sided protective polarizing film or optical film with the adhesive layer of the present invention, or a suitable liquid crystal display device such as a backlight or a reflective plate used in the lighting system . In this case, the single-sided protective polarizing film or optical film with the adhesive layer of the present invention can be arranged on one side or both sides of the liquid crystal element. When the single-sided protective polarizing film or optical film with the adhesive layer of the present invention is arranged on both sides, they may be the same or different. In addition, when forming a liquid crystal display device, suitable parts such as diffuser, anti-glare layer, anti-reflection film, protective plate, ridge array, lens array sheet, light diffuser, backlight, etc. can be arranged in an appropriate position. Or more than 2 layers.

Examples Hereinafter, examples are given to illustrate the present invention, but the present invention is not limited to the examples shown below. In addition, the parts and% in each example are based on weight. The following unspecified room temperature storage conditions are 23°C 65%RH.

＜Single-side protective polarizing film＞ (Production of polarizer) Amorphous isophthalic acid-copolymer-polyethylene terephthalate (IPA-copolymer-PET) film with water absorption rate of 0.75% and Tg75℃ (thickness : 100μm) One side of the substrate is corona treated, and the corona treated surface is coated at 25°C and contains polyvinyl alcohol in a ratio of 9:1 (polymerization degree 4200, saponification degree 99.2 mol%) And acetyl acetyl modified PVA (polymerization degree 1200, acetyl acetyl modified degree 4.6%, saponification degree 99.0 mol% or more, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name "Gohsefimer Z200") It was dried to form a PVA-based resin layer with a thickness of 11 μm to produce a laminate. The obtained laminate was subjected to uniaxial stretching of the free end (in-air auxiliary stretching treatment) at 2.0 times the longitudinal direction (longitudinal direction) between rollers having different peripheral speeds in an oven at 120°C. Next, the layered body was immersed in an insolubilization bath (a boric acid aqueous solution obtained by mixing 4 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 30°C for 30 seconds (insolubilization treatment). Next, while immersing in a dyeing bath with a liquid temperature of 30°C, the iodine concentration and immersion time were adjusted so that the polarizing plate had a desired transmittance. In this example, it was immersed in an iodine aqueous solution obtained by mixing 0.2 parts by weight of iodine and 1.0 part by weight of potassium iodide with respect to 100 parts by weight of water for 60 seconds (dyeing treatment). Next, it was immersed in a crosslinking bath (a boric acid aqueous solution obtained by mixing 3 parts by weight of potassium iodide and 3 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 30°C for 30 seconds (crosslinking treatment). Then, while immersing the layered body in an aqueous solution of boric acid at a liquid temperature of 70°C (an aqueous solution obtained by mixing 4 parts by weight of boric acid and 5 parts by weight of potassium iodide with respect to 100 parts by weight of water), rolls with different peripheral speeds Uniaxial stretching is performed between the cylinders so that the total stretching magnification in the longitudinal direction (longitudinal) reaches 5.5 times (underwater stretching treatment). Then, 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) having a liquid temperature of 30°C (washing treatment). Through the above, an optical thin film laminate containing a polarizer with a thickness of 5 μm was obtained.

(Production of protective film) Protective film: A (meth)acrylic resin film having a lactone ring structure with a thickness of 40 μm is corona treated and used on the easy-to-adhesive surface.

(Applicable to the production of adhesives for protective films) Combine 40 parts by weight of N-hydroxyethyl acrylamide (HEAA), 60 parts by weight of acryloyl mopholine (ACMO), and photoinitiator "IRGACURE 819" (BASF Made by the company) 3 parts by weight are blended to prepare an ultraviolet curable adhesive.

(Production of single-sided protective polarizing film) On the surface of the polarizer of the above-mentioned optical film laminate, the above-mentioned ultraviolet curable adhesive is applied so that the thickness of the adhesive layer after curing becomes 0.5μm, and the above-mentioned Protect the film, and then irradiate ultraviolet rays as active energy rays to harden the adhesive. Ultraviolet rays are irradiated using a gallium-enclosed metal halide lamp, irradiation device: Light　HAMMER10 manufactured by Fusion UV Systems, Inc., bulb: V bulb, peak illuminance: 1600mW/cm2, cumulative irradiation amount 1000/mJ/cm2 (wavelength 380~ 440nm), and the illuminance of the ultraviolet rays is measured using the Sola-Check system manufactured by Solarell. Next, the amorphous PET substrate was peeled off to produce a single-sided protective polarizing film (total thickness 45.5 μm) using a thin polarizer. The optical properties of the obtained single-sided protective polarizing film were 42.8% monomer transmittance and 99.99% polarization degree.

<Monomer transmittance T and polarization degree P> Using a spectroscopic transmittance measuring device with integrating sphere (Dot-3c of Murakami Color Research Institute), measure the monomer transmittance T and of the obtained single-sided protective polarizing film Polarization degree P. In addition, the degree of polarization P is determined by the transmittance (parallel transmittance: Tp) when two identical polarizing films are overlapped with their transmission axes in parallel, and the transmission axes of the two are positive. The transmittance in the case of overlapping (orthogonal transmittance: Tc) is obtained by applying the following formula. Polarization P(%)={(Tp-Tc)/(Tp＋Tc)} ^1/2 ×100 Each transmittance is set to 100% of the fully polarized light obtained through the Glan-Taylor polarizer, and used As shown by the Y value for visual sensitivity compensation of 2 degrees viewing angle (C light source) of JIS Z8701.

(Transparent resin layer forming material: coating liquid) Dissolve polyvinyl alcohol resin with a degree of polymerization of 2500 and a degree of saponification of 99.7 mol% in pure water to prepare an aqueous solution with a solid content of 4% by weight and a viscosity of 60 mPa∙s (coating liquid).

(Preparation of acrylic polymer) A monomer mixture containing 99 parts of butyl acrylate and 1 part of 4-hydroxybutyl acrylate was charged into a 4-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler. And with respect to 100 parts of the aforementioned monomer mixture (solid content), 0.1 part of 2,2´-azobisisobutyronitrile as a polymerization initiator was added together with ethyl acetate, and nitrogen was introduced while stirring slowly. After the nitrogen substitution, the liquid temperature in the flask was maintained at about 60°C to carry out the polymerization reaction for 7 hours. After that, ethyl acetate was added to the obtained reaction liquid to prepare an acrylic polymer solution whose solid content was adjusted to a concentration of 30% and a weight average molecular weight of 1.4 million.

(Preparation of the adhesive composition) To 100 parts of the solid content of the acrylic polymer solution, 0.1 part of trimethylolpropane xylylene diisocyanate (manufactured by Mitsui Chemicals: TAKENATE D110N) and diphenylmethyl cyanide were blended 0.3 parts of base peroxide and 0.075 parts of γ-glycidoxypropylmethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-403) to prepare an acrylic adhesive solution.

(Formation of Adhesive Layer) Next, the above-mentioned acrylic adhesive solution was uniformly coated on the surface of the polyethylene terephthalate film (separation film) treated with a silicone release agent using a jet knife coater , And dry for 2 minutes in an air circulation constant temperature oven at 155℃ to form an adhesive layer with a thickness of 20μm on the surface of the separation film.

Example 1 <Production of a single-sided protective polarizing film with a transparent resin layer> On the polarizer surface of the above-mentioned single-sided protective polarizing film conveyed at 20m/min (the surface of the polarizer without a protective film), a coating device was used (Specifically, a gravure coater) Coat the transparent resin layer forming material (coating liquid) so that the thickness after drying becomes 1μm, and then dry it with hot air at 85°C for 30 seconds to produce a sheet with a transparent resin layer Surface protection polarizing film.

(Production of polarizing film with adhesive layer) Next, without winding the single-sided protective polarizing film with a transparent resin layer obtained above into a roll, then (specifically, 18 seconds later) on the transparent resin layer The adhesive layer that has been formed on the peeling treatment surface in the release sheet (separator) is attached on top to make a polarizing film with the adhesive layer. Afterwards, the polarizing film with the adhesive layer is rolled up to make a roll.

In the examples, after manufacturing a single-sided protective polarizing film with a transparent resin layer and before bonding the adhesive layer, the film thickness of the transparent resin layer was measured using a device (measuring device for film thickness: optical spectroscopy) Device: USB2000+ manufactured by Ocean Optics, light source: HL-2000, optical fiber: ZFQ-12796 (200μm reflective fiber), polarizing element: the single-sided protective polarizing film obtained above). In terms of measurement conditions, the measurement wavelength: 450 nm to 800 nm, and the refractive index of the transparent resin layer: 1.51. The film thickness of the transparent resin layer obtained in the example is 1.0±0.1 μm, which is quite stable.

Comparative Example 1 A single-sided protective polarizing film with a transparent resin layer was produced in the same manner as in the examples, and it was wound into a roll. Then, I tried to output from a roll of a polarizing film with a transparent resin layer on one side, but the roll could not be output due to agglomeration of the roll.

Comparative Example 2 A single-sided protective polarizing film with a transparent resin layer was produced in the same manner as in the examples, and a separator was attached to the polarizing film to be wound to form a roll. Then, it tried to output from a roll of a polarizing film with a transparent resin layer on one side, but the adhesion between the transparent resin layer and the separator was weak and wrinkles and squeezing occurred during transportation, so cracks occurred as soon as it was transported.

The risk of occurrence of nano-slits in the examples is low, and on the contrary, the risk of occurrence of nano-slits in the comparative examples is high.

1‧‧‧Single-sided protective polarizing film 10‧‧‧Polarizer 20‧‧‧Protective film 2´‧‧‧Coating liquid 2‧‧‧Transparent resin layer 3‧‧‧Adhesive layer 40‧‧‧Light source 41‧‧‧Polarizer A‧‧‧Single-side protective polarizing film with transparent resin layer B‧‧‧Single-side protective polarizing film with adhesive layer

Fig. 1 is a conceptual diagram showing an example of an embodiment related to the manufacturing method of the present invention. Fig. 2 is a conceptual diagram showing an example of an embodiment related to step (4) in the manufacturing method of the present invention. Figure 3(A)-(B) is an example of a conceptual diagram comparing the nano slits and through cracks generated in the polarizer.

1‧‧‧Single-sided protective polarizing film

10‧‧‧Polarizer

20‧‧‧Protective film

2′‧‧‧Coating liquid

2‧‧‧Transparent resin layer

3‧‧‧Adhesive layer

A‧‧‧Single-side protective polarizing film with transparent resin layer

B‧‧‧Single-side protective polarizing film with adhesive layer

Claims (9)

A method for manufacturing a single-sided protective polarizing film with an adhesive layer. The single-sided protective polarizing film has a protective film on only one side of the polarizer, and the single-sided protective polarizing film with the adhesive layer is made from The single-sided protective polarizing film has a transparent resin layer and an adhesive layer in this order from the polarizer side. The manufacturing method is characterized in that the polarizer contains a polyvinyl alcohol-based resin and has a thickness of 10 μm or less, and is structured to The optical characteristics represented by the monomer transmittance T and the polarization degree P satisfy the conditions of the following formula: P>-(10 ^0.929T-42.4 -1)×100 (only T<42.3), or P≧99.9 (only T≧42.3) ); The aforementioned transparent resin layer and adhesive layer are formed by performing the following steps (1) and (2) to form a transparent resin layer with a thickness of less than 3μm, and then performing the following step (3) to form the adhesive layer: Step (1) is to apply a coating solution containing a resin component or a curable component to the polarizer side of the single-sided protective polarizing film while conveying the single-sided protective polarizing film, and the curable component can form a resin layer Step (2), which is to cure or harden the coating liquid after the coating step (1); Step (3), which is not to roll the resulting single-sided protective polarizing film with a transparent resin layer When rolled, an adhesive layer is formed on the transparent resin layer. For example, the method for manufacturing a single-sided protective polarizing film with an adhesive layer in claim 1, which has step (4) after the aforementioned step (2) and before the aforementioned step (3), and measures the transparent resin layer in the conveying line Film thickness. Such as Claim 2 of the manufacturing method of a single-sided protective polarizing film with an adhesive layer, wherein the aforementioned step (4) is performed by an optical interference method using a polarizing element at the front end of the light source. For example, the method for manufacturing a single-sided protective polarizing film with an adhesive layer of claim 1, wherein the coating liquid of the aforementioned step (1) contains a resin component that has been dissolved or dispersed in water, and is cured in step (2) To form a transparent resin layer. According to claim 4, the method for manufacturing a single-sided protective polarizing film with an adhesive layer, wherein the coating liquid containing the resin component is an aqueous solution containing a polyvinyl alcohol-based resin. Such as claim 1 of the manufacturing method of a single-sided protective polarizing film with an adhesive layer, wherein the viscosity of the coating solution of the aforementioned step (1) at 25° C. is 1000 mPa. s or less. According to claim 1, the method for manufacturing a single-sided protective polarizing film with an adhesive layer, wherein the aforementioned polarizing member contains 20% by weight or less of boric acid relative to the total amount of the polarizing member. The method for manufacturing a single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 7, wherein a separator is laminated on the adhesive layer. For example, the manufacturing method of the single-sided protective polarizing film with an adhesive layer of claim 8, which is to make the single-sided protective polarizing film with the adhesive layer into a winding.

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