KR20150056823A - Display device with touch panel - Google Patents

Abstract

In the display device with the touch panel, the electrode layer of the touch panel 20 is composed of one layer, and the conductive film 24 is bonded on the electrode layer. The conductive film 24 has a shatterproof film 25 including a cellulose ester film and a conductive layer 26 formed by water-based application of a conductive material. In the polarizing plate (2) of the display device 10, the film of the display panel 1 with respect to the polarizer 3 side (5), the moisture permeability 200g / m is the optical film of ² / 24h or less. The film 4 on the touch panel side with respect to the polarizer 3 includes a cellulose ester film having a thickness of 15 to 30 占 퐉 and having a plasticizer and is provided on the side opposite to the side where the plasticizer is largely deviated in the thickness direction of the film And UV-adhered to the polarizer 3 via the surface.

Description

[0001] DISPLAY DEVICE WITH TOUCH PANEL [0002]

The present invention relates to a display device in which a touch panel and a display device are bonded to each other with a pressure-sensitive adhesive layer interposed therebetween.

2. Description of the Related Art Recently, various kinds of electronic devices such as mobile phones, portable terminals, personal computers, and the like have become more sophisticated and diversified, and touch panels have been used as one of input means to their electronic devices. The touch panel has light transmittance. When the touch panel is bonded to a liquid crystal display device, for example, the touch panel is attached to the polarizing plate side of the liquid crystal panel through an adhesive.

2. Description of the Related Art Conventionally, a touch panel mounted on the surface of an information display unit of a portable terminal has been made of a plastic plate having high light transmittance in order to make information displayed on the information display unit easy to see and to prevent breakage even when the portable terminal is dropped. However, if the thickness of the plastic plate is reduced in order to reduce the thickness and weight required for the portable terminal, the strength of the plastic plate is insufficient. In order to solve this problem, a glass substrate having higher strength than a plastic plate has recently been used for a touch panel mounted on the surface of the information display unit.

However, when the glass substrate is used, the glass substrate may be broken when the portable terminal is dropped, and the fragments may be scattered. Therefore, it has conventionally been studied to use a glass shatterproof film bonded to the surface of a glass substrate. In general, a polyethylene terephthalate (PET) film, which is inexpensive and has a shatterproof effect, is used as a glass shatterproof film. Since the PET film generally has low adhesion with the pressure-sensitive adhesive layer, a PET film having an easy-to-adhere layer provided with a thin film called an easy-to-adhere layer is used in order to improve the adhesion.

However, in the PET film, interference fringes are generated in relation to the refractive index, and the visibility of the display information is sometimes lowered. In order to solve this problem, it has been studied to prevent scattering of a glass substrate by using a triacetyl cellulose film having a pressure-sensitive adhesive layer instead of a PET film as a protective film on the outermost surface of the glass substrate (see, for example, 1).

On the other hand, there are various types of touch panels, and one of them is a capacitive touch panel. In this capacitive touch panel, an X electrode pattern formed to extend in the X direction by a transparent conductive film and a Y electrode pattern formed to extend in the Y direction by another transparent conductive film are provided on a transparent substrate have. As the X electrode pattern and the Y electrode pattern, there are, for example, a pattern of a rectangular shape or a diamond pattern, which are formed by using ITO (Indium Tin Oxide). When the surface of the substrate of the touch panel is pressed with a finger, the X electrode pattern and the Y electrode pattern come into contact with each other, and the capacitance at the position changes, so that the change in the capacitance is detected through the X electrode pattern and the Y electrode pattern Whereby the pressing position can be specified.

In a capacitive touch panel having such a two-layered transparent conductive film and a touch surface as a glass surface, a two-layered transparent conductive film is provided with a transparent optical adhesive tape (OCA) And the glass substrate is further bonded again through the through-hole, the touch panel becomes thick. In this respect, in the capacitive touch panel of Patent Document 2, two transparent conductive films extending in mutually orthogonal directions are provided, and in the configuration in which the touch surface is a glass substrate, The thickness of the touch panel as a whole can be reduced.

However, when a thin touch panel using only one glass substrate such as the one described in Patent Document 2 is bonded to a liquid crystal display device, for example, as a display device through a pressure-sensitive adhesive layer, the electrode layer (X electrode pattern, Is closer to the liquid crystal panel. This makes it easy to be influenced by electrical noise (including leakage current) generated by switching ON / OFF of switching elements (for example, TFTs) provided corresponding to each pixel at the time of driving each pixel of the liquid crystal panel (For example, the pressing position can not be detected with high accuracy by the noise).

Further, in the construction in which two electrode layers are formed on a glass substrate, when either of the two electrode layers is disconnected at the time of cutting the glass substrate, it becomes a defective product. As a result, there is a high probability of becoming a defective product, resulting in a decrease in the yield and in the productivity of the touch panel.

On the other hand, the touch panel of Patent Document 3 adopts a configuration in which only one electrode layer is provided on the substrate, and a shield layer is formed on the opposite side of the electrode layer to the substrate. By making the electrode layer a single layer, it is possible to avoid a reduction in the yield due to disconnection of the electrode layer at the time of cutting the glass substrate and to prevent the electrical noise from the display panel from being blocked by the shield layer. .

Japanese Patent Laid-Open Publication No. 2011-209512 (see claim 1, paragraph [0012], Fig. 1, etc.) Japanese Patent Application Laid-Open No. 2011-186717 (Claim 1, paragraphs 0016, 0022, etc.) Japanese Unexamined Patent Application Publication No. 2008-008255 (see paragraph [0107], Fig. 4, etc.)

Incidentally, the polarizing plate of the liquid crystal display device to which the touch panel is bonded employs a structure in which the polarizer is sandwiched between the surface protective film (the film on the touch panel side) and the backside protective film (the film on the display panel side). At this time, as a bonding method of the surface protective film and the back surface protective film to the polarizer, there is a method of bonding by ultraviolet irradiation (UV irradiation). This method forms a polarizing plate by applying an ultraviolet curable adhesive to the front and back surfaces of the polarizer, and then UV-irradiating the adhesive with the polarizer sandwiched between the surface protective film and the back protective film and curing the adhesive . However, when UV irradiation is performed, the orientation of the polarizer is disturbed by the curing shrinkage of the adhesive at the time of UV irradiation, and the contrast is lowered.

Further, for example, when the above-mentioned shielding layer is bonded to a film by water-based coating or the polarizer is made of a PVA (polyvinyl alcohol) film, moisture is contained in the shielding layer and the polarizer. At this time, if the moisture permeability of the back surface protective film of the polarizer is high, the moisture is absorbed in the back surface protective film, and the retardation of the back surface protective film fluctuates. Since the back side protective film is located on the display panel side with respect to the polarizer, if the retardation of the back side protective film fluctuates, display unevenness such as white spots occurs in black display.

In addition, if the glass substrate is located on the outermost layer (the layer on the opposite side of the display device) of the touch panel, the moisture can not pass through the glass substrate and can not escape to the outside of the touch panel. Then, the polarizer is deteriorated by the above-mentioned moisture, and the display may become reddish when the black display is performed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a structure in which a protective film is adhered to both surfaces of a polarizer through an ultraviolet curable adhesive while suppressing a decrease in yield of a touch panel and malfunction due to electrical noise, Which is capable of suppressing the orientation disorder of the polarizer caused by the curing shrinkage of the protective film, the retardation fluctuation of the back protective film, and the deterioration due to moisture of the polarizer.

The above object of the present invention is achieved by the following constitution.

1. A display device having a touch panel in which the electrode layer side of a touch panel having an electrode layer on a glass substrate and the polarizing plate side of a display device having a polarizing plate on a display panel are bonded to each other with an adhesive layer interposed therebetween,

Wherein the electrode layer of the touch panel is composed of one layer, a conductive film is bonded on the electrode layer,

Wherein the conductive film comprises a film of a scattering prevention film for preventing scattering of the glass substrate, the film including a cellulose ester film, and a conductive layer formed on the opposite side of the electrode layer from the scattering- Lt; / RTI >

The polarizing plate includes a polarizer, a surface protective film adhered to the touch panel side of the polarizer through an ultraviolet curable adhesive, and a back surface protective film adhered to the display panel side of the polarizer through an ultraviolet curable adhesive However,

And the back protective film, the moisture permeability 200g / m of the optical film ² / 24h or less,

The surface protective film is a cellulose ester film having a thickness of 15 to 30 탆 and having a plasticizer and is bonded to the polarizer via a surface opposite to the side where the plasticizer is largely deviated in the thickness direction of the film A display device with a touch panel.

2. The display device with a touch panel according to 1 above, wherein the polarizing plate further has a hard coating layer on the side opposite to the polarizer with respect to the surface protective film.

3. The display device according to the above 1 or 2, wherein the conductive material is a conductive fiber.

4. The display device with the touch panel according to 3 above, wherein the conductive fibers are metal nanowires.

5. The touch panel display according to any one of 1 to 4 above, wherein the optical film of the back side protective film is a film comprising any one of acrylic, cyclic polyolefin and polycarbonate. Device.

According to the above configuration, in the touch panel, since the electrode layer on the glass substrate is one layer, it is possible to suppress the decrease in the yield due to the disconnection of the electrode layer when cutting the glass substrate, and consequently, the decrease in the productivity of the touch panel. In addition, scattering of the glass substrate due to impact or the like can be prevented by the scattering prevention film, and electrical noise from the display device can be blocked by the conductive layer, so that malfunction of the touch panel can be suppressed.

In the configuration in which the surface protective film is bonded to the polarizer through an ultraviolet curable adhesive, the surface protective film is bonded to the polarizer through the surface opposite to the side where the plasticizer is largely deviated in the thickness direction of the cellulose ester film Therefore, curing shrinkage of the adhesive due to ultraviolet irradiation is suppressed, and a large amount of plasticizer is disposed on the surface of the touch panel side, so that the stress when the touch panel is pressed can be absorbed by the cellulose ester film. As a result, it is possible to suppress the alignment disorder of the polarizer and suppress the decrease in contrast.

In addition, the back surface of the polarizing plate protective film, the moisture permeability and includes an optical film of less than 200g / m ² / 24h. Thereby, the moisture of the conductive layer formed by the water-based coating or the moisture of the polarizer (for example, PVA) is inhibited, and the retardation of the back surface protective film is prevented from fluctuating by the moisture And it is possible to suppress occurrence of display irregularities such as white spots when displaying black.

In addition, since both the scattering-preventive film and the surface protective film of the polarizing plate contain a cellulose ester film having high hygroscopicity and moisture permeability, the moisture can be trapped (trapped) on both cellulose ester films. Thereby, deterioration of the polarizer by the moisture can be suppressed, and it is possible to suppress the display of reddishness in black display.

In addition, since the cellulose ester film of the surface protective film has a thickness of 15 to 30 탆 and is thin, water is liable to be released from the polarizer through the surface protective film to the shatterproof film, and deterioration due to moisture of the polarizer can be reliably suppressed have.

1 is a cross-sectional view showing a schematic configuration of a display device with a touch panel according to an embodiment of the present invention.

An embodiment of the present invention will be described below with reference to the drawings. In the present specification, when the numerical ranges are denoted by A to B, the lower limit (A) and the upper limit (B) are included in the numerical range.

[Display device with touch panel]

1 is a cross-sectional view showing a schematic configuration of a display device with a touch panel according to the present embodiment. As shown in Fig. 1, a display device with a touch panel is constructed by bonding a display device 10 and a touch panel 20 via a pressure-sensitive adhesive layer 30.

The display device 10 is constituted by laminating a polarizing plate 2 on a display panel 1. The display panel 1 can be constituted by a liquid crystal display panel (LCD) or an organic light-emitting diode (OLED) display. The LCD or OLED has a plurality of pixels arranged in a matrix, and display is performed by turning on / off the driving of each pixel by a switching element such as a TFT (Thin Film Transistor). When the display panel 1 is an LCD, another polarizing plate (not shown) is disposed on the opposite side of the display panel 1 from the polarizing plate 2.

The polarizing plate 2 includes a polarizer 3 that transmits a predetermined linearly polarized light, a film 4 that is laminated on the touch panel 20 side of the polarizer 3, (Back-side protective film). The polarizer 3 is obtained by, for example, dying a polyvinyl alcohol film with a dichroic dye and stretching it at a high magnification, and after the film is subjected to an alkali treatment (also referred to as saponification treatment), the polarizing film 3, 3) bonded to each side via an ultraviolet curable adhesive, and the adhesive is adhered by removing the solvent by drying and curing the adhesive by ultraviolet irradiation (UV irradiation).

The film 4 is formed as a hard coating film in which a hard coating layer 4b is laminated on a film base 4a (surface protective film) and has a function of protecting the surface of the polarizing plate 2 (polarizer 3) Lt; / RTI > The film substrate 4a can be composed of various materials, but in the present embodiment, it is composed of a cellulose ester film having a thickness of 15 to 30 占 퐉. Cellulose ester film, the moisture permeability is increased to about 800g / m ² / 24h, it is excellent in moisture absorption in the thickness 80㎛ terms.

The hard coat layer 4b is made of, for example, an active energy ray hardening type resin, and its thickness is several 탆. The film 4 may be formed as a protective film alone (without laminating a hard coating layer), but the film 4 may be formed as a hard coating film in which the hard coating layer 4b is formed on the film base 4a, The function of protecting the surface of the substrate 2 can be enhanced. Particularly, in this embodiment, since the film base 4a is a thin film, the display panel 1 is likely to be damaged when the touch panel is pressed. However, by making the film 4 a hard coating film, .

The film substrate 4a has a plasticizer. Details of the material of the plasticizer will be described later, but the plasticizer is added to the cellulose ester film for the purpose of improving the moisture permeability, the fluidity of the composition, and the flexibility of the film. The cellulose ester film can be formed by a solution casting film forming method to be described later. At this time, the solvent is evaporated on the support on which the dope is made flexible, so that the plasticizer tends to be unevenly distributed in the thickness direction of the film. In other words, the concentration of the plasticizer increases on one side of the center in the thickness direction of the film, and decreases on the other side. In the present embodiment, the surface (i.e., the harder side) opposite to the side (i.e., the softer side) on the side where the plasticizer is largely deviated in the thickness direction in the film base 4a is attached to the polarizer 3 ), And the adhesive surface and the polarizer 3 are bonded to each other with an ultraviolet curable adhesive.

Further, the side on which the plasticizer is largely deviated can be specified by, for example, analysis with a time-of-flight secondary ion mass spectrometer (TOF-SIMS).

The hard coating layer 4b is formed on the surface of the film base 4a where the plasticizer is largely deviated (the surface opposite to the polarizer 3).

When the display panel 1 is an OLED, it is preferable that the polarizing plate 2 is configured as a circularly polarizing plate (or an elliptically polarizing plate) for preventing reflection of external light. The film 5 on the display panel 1 side of the polarizer 3 is an optical film which gives an in-plane retardation of about 1/4 of the wavelength of the transmitted light, It is preferable that the polarizer 3 and the film 5 are bonded to each other such that the optical axis (transmission axis or absorption axis) and the slow axis of the film 5 cross at an angle of about 45 degrees.

When the display panel 1 is an LCD, the film 5 may be simply provided as a protective film of a polarizer, or may be a protective film serving also as a retardation film having a desired optical compensation function. As described above, when the display panel 1 is an OLED display, it is preferable that the film 5 is an optical film that gives an in-plane retardation of about 1/4 of the transmission wavelength.

In addition, the film 5 in the present embodiment, the water vapor permeability are configured to 200g / m ² / 24h or less the optical film. As such an optical film, a film containing a resin of acrylic, cyclic polyolefin (COP), polycarbonate (PC) can be used. By the way, say, the moisture permeability of acrylic is a 100g / m ² /24h.40㎛, water vapor transmission rate of the COP is 0.1g / m ² /24h.40㎛, the PC moisture permeability is on the order of 100g / m ² /24h.40㎛. In the present invention, the water vapor permeability refers to a value measured at a test condition of 40 ° C and 90% RH.

This optical film water vapor transmission rate is more than 200g / m ² / 24h is so installed in the display panel (1) side of the polarizer 3, the time by the moisture is the phase difference of the optical film changes, and the display panel (1) It is possible that the amount of light decreases when the polarized state of light from the polarizer 3 changes according to the optical film and passes through the polarizer 3. On the other hand, even if the retardation film 25 and the surface protective film (film base 4a), which will be described later, provided outside the polarizer 3 fluctuate due to moisture, there is no influence on the polarization state, A cellulose ester film having high water absorption and high water absorption can be preferably used.

The touch panel 20 is a capacitance type touch panel and includes an electrode pattern 22 (electrode layer) including a transparent conductive film (for example, ITO) and an interlayer insulating layer 23 on the glass substrate 21, Lt; / RTI > That is, in the touch panel 20, the glass substrate to be used is only one glass substrate 21, and the touch panel 20 of the thin type is formed in comparison with the configuration using two glass substrates.

The surface of the glass substrate 21 (the surface opposite to the electrode pattern 22) is the touch surface of the touch panel 20. The electrode pattern 22 is formed on the glass substrate 21 so as to extend in one direction (for example, the X direction). The interlayer insulating layer 23 is formed on the glass substrate 21 so as to cover the electrode pattern 22.

When the surface of the touch panel 20 is pressed with a finger, the electrode pattern 22 is grounded through the human body at the touched point, and a change occurs in the resistance value between the electrode pattern 22 and the ground line. The change of the resistance value is detected by an external detection circuit connected to the electrode pattern 22, whereby the coordinate of the touched point is specified.

A conductive film 24 is bonded to the electrode pattern 22 (on the interlayer insulating layer 23) through a pressure-sensitive adhesive layer (not shown). The conductive film 24 has a shrinkage preventing film 25 and a conductive layer 26.

The anti-scattering film 25 includes a cellulose ester film and is provided to prevent scattering of the glass substrate 21 due to an external impact or the like. As the cellulose ester film, a cellulose triacetate film having an in-plane retardation (Ro) of 0 nm to 10 nm can be used. In this case, since the interference due to the in-plane retardation is small, the visibility when the display panel 10 is visually recognized through the touch panel 20 can be improved.

In the case where the retardation Ro in the in-plane direction of the scattering prevention film 25 is 0 nm to 10 nm, the joining angle of the scattering prevention film 25 with respect to the polarizer 3 is set to 0 to 15 degrees . Here, the bonding angle is an angle formed by the optical axis (transmission axis or absorption axis) of the polarizer 3 and the slow axis of the scattering prevention film 25. The direction of the slow axis of the scattering prevention film 25 at this time was determined by measuring the average in-plane refractive index of the sample at a wavelength of 590 nm under the environment of a temperature of 23 캜 and a relative humidity of 55% RH by the Abbe's refractive index meter (1T) Can be obtained. With such an angle, even if the retardation in the in-plane direction of the anti-scattering film is slightly changed, the optical effect can be reduced.

A cellulose diacetate film having an in-plane retardation (Ro) of 30 nm to 200 nm may be used as the cellulose ester film of the shake-prevention film (25). In this case, it is preferable that the slow axis of the scattering prevention film is arranged to be in a direction of 10 to 80 degrees with respect to the optical axis (transmission axis or absorption axis) of the polarizer 3. With this configuration, since the linearly polarized light transmitted through the polarizer 3 can be changed to elliptically polarized light or circularly polarized light, it is possible to improve the visibility when viewing the display device 10 by using polarized sunglasses.

The conductive layer 26 is formed by water-based coating of a conductive material on the side opposite to the electrode pattern 22 with respect to the scattering-preventing film 25. As the conductive material, conductive fibers or conductive polymers including metal nanowires such as silver nanowires (AgNW) and copper nanowires (CuNW) can be used. Among them, conductive fibers are preferably used. Details of conductive fibers such as metal nanowires will be described later.

The pressure sensitive adhesive layer 30 is formed on the entire surface of the polarizing plate 2 of the display device 10 and is provided on the touch panel 20 and the display device 10. The pressure sensitive adhesive layer 30 is made of an adhesive layer such as OCA or UV curable resin Respectively.

The electrode layer on the glass substrate 21 is one layer of the electrode pattern 22 in the touch panel 20 so that the thickness of the electrode layer 22 in the case of cutting the glass substrate 21 It is possible to suppress a reduction in the yield due to disconnection of the electrode layer and hence a decrease in the productivity of the touch panel 20. [

Since the conductive film 24 bonded to the electrode pattern 22 has the scattering prevention film 25, scattering of the glass substrate 21 due to impact or the like is prevented by the scattering prevention film 25 can do. Further, in the case of the thin configuration in which the glass substrate to be used is one, the touch panel 20 becomes close to the display device 10, and it becomes easy to receive electrical noise from the display device 10. [ However, since the conductive film 26 has the conductive layer 26, the electrical noise can be blocked by the conductive layer 26, and even if such a thin configuration is used, the malfunction of the touch panel 20 due to the electrical noise Can be suppressed.

In particular, by using conductive fibers including metal nanowires as a conductive material and applying this aqueous coating, it is possible to reliably realize the conductive layer 26 for blocking electrical noise.

In the case where the film 4 and the film 5 of the polarizing plate 3 are bonded to the polarizer 3 via an ultraviolet curable adhesive, the film 4 includes a cellulose ester film, Is adhered to the polarizer 3 via the surface opposite to the side on which the plasticizer is largely deviated in the cellulose ester film. As a result, curing shrinkage of the adhesive during UV irradiation is suppressed, and a large amount of plasticizer is disposed on the surface of the touch panel 20 side, and the stress when the touch panel 20 is pressed is higher than that of the cellulose ester film Can be absorbed. As a result, the alignment disorder of the polarizer 3 can be suppressed, and the decrease in contrast can be suppressed.

Further, when the hard coat layer 4b is provided on the side of the film 4 (cellulose ester film) on the side where the plasticizer is larger, the surface of the film 4 is softened so that the stress when the touch panel 20 is pressed The hard coating film can be hardly broken.

In addition, the film of the polarizing plate 3 (5), the moisture permeability and includes an optical film of less than 200g / m ² / 24h. As a result, the moisture of the conductive layer 26 formed by the water-based coating or moisture of the polarizer 3 becomes difficult to transmit through the film 5, so that the phase difference of the film 5 fluctuates due to the above- Can be suppressed. As a result, it is possible to suppress display unevenness such as white spots in black display.

In particular, by using a film containing any one of acrylic, cyclic polyolefin and polycarbonate as the optical film having a low moisture permeability, the above effect can be surely obtained.

In addition, since the glass substrate is located on the outermost surface of the touch panel 20, the moisture can not escape to the outside of the touch panel 20 and is trapped between the glass substrate 21 and the film 5. However, since both the scattering-preventive film 25 of the conductive film 24 and the film 4 of the polarizing plate 3 contain a cellulose ester film having high hygroscopicity and moisture permeability, the moisture can be passed through both cellulose ester films (Trapped) at the same time. Thereby, deterioration of the polarizer 3 by the moisture can be suppressed, and it is possible to suppress the display of reddishness in black display.

In addition, since the cellulose ester film of the film 4 has a thickness of 15 to 30 탆 and is thin, water is likely to escape from the polarizer 3 to the scattering prevention film 25 through the film 4, 3) due to moisture can be reliably suppressed.

[About Polarizer]

Hereinafter, the details of each layer constituting the polarizing plate 2 will be described. The protective film (surface protective film, back protection film) and hard coating layer shown below can also be applied to the scattering prevention film 25 of the touch panel 20.

[Protection film]

The film base material 4a, which is the protective film on the side of the touch panel 20 of the polarizing plate 2, is composed of a cellulose ester film having a thickness of 15 to 30 mu m. The cellulose ester resin used will be described later in detail.

As the polarizing plate (2) a display panel (1) a protective film of a film (5) on the side of, without particular limitation, may be used a thermoplastic resin or a thermosetting resin, and the moisture permeability is preferably as 200g / m ² / 24h or less film Specifically, it is preferable to constitute an optical film including an acrylic resin, a cyclic polyolefin (COP), a polycarbonate (PC), and the like.

(Thermoplastic resin)

The thermoplastic resin which can be used for the film 5 refers to a resin that is softened by heating to a glass transition temperature or melting point and can be molded into a desired shape.

Examples of the general thermoplastic resin include cellulose ester, polyethylene (PE), high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene Polyvinyl acetate (PVAc), Teflon (polytetrafluoroethylene, PTFE), ABS resin (acrylonitrile butadiene styrene resin), AS resin, acrylic resin (PMMA) and the like can be used.

Particularly, when strength or fragility is required, it is possible to use polyamide (PA), nylon, polyacetal (POM), polycarbonate (PC), modified polyphenylene ether (m-PPE, modified PPE, PPO) Butylene terephthalate (PBT), polyethylene terephthalate (PET), glass fiber reinforced polyethylene terephthalate (GF-PET), and cyclic polyolefin (COP).

In addition, when high heat distortion temperature and long-term usable characteristics are required, it is possible to use polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polysulfone, polyethersulfone, amorphous polyarylate, Polyether ether ketone, thermoplastic polyimide (PI), polyamideimide (PAI), and the like.

In this embodiment, it is preferable to use a cellulose ester resin as the film base 4a from the viewpoint of the effects of the present embodiment, and as the film 5, a polycarbonate resin, a polyethylene terephthalate resin, It is preferable to use an acrylic resin or a polyolefin resin.

Hereinafter, in the present embodiment, the cellulose ester resin suitably used for the film substrate 4a will be described in detail.

<Cellulose ester resin>

The cellulose ester resin usable for the film (4a) in the present embodiment is a cellulose ester resin selected from the group consisting of cellulose (di (tri)) acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate and cellulose phthalate At least one kind selected from the group consisting of

Particularly preferred cellulose esters among these are cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate and cellulose acetate butyrate.

As the substitution degree of the mixed fatty acid ester, it is more preferable that the lower fatty acid ester of cellulose acetate propionate or cellulose acetate butyrate has an acyl group having 2 to 4 carbon atoms as a substituent, a degree of substitution of the acetyl group as X, (I) and (II) when the degree of substitution of the hydroxyl group, the hydroxyl group or the butyryl group is Y,

In formula (I) 2.6? X + Y? 3.0

The formula (II) 1.0? X? 2.5

Of these, cellulose acetate propionate is preferably used, and among these, it is preferable that 1.9? X? 2.5 and 0.1? Y? 0.9. The part which is not substituted in the acyl group usually exists as a hydroxyl group. These can be synthesized by a known method.

The cellulose ester used in the present embodiment preferably has a weight-average molecular weight (Mw) / number-average molecular weight (Mn) ratio of 1.5 to 5.5, particularly preferably 2.0 to 5.0, Preferably 5.0 to 5.0, and more preferably 3.0 to 5.0.

The raw cellulose of the cellulose ester used in the present embodiment may be a wood pulp or a cotton linter. The wood pulp may be either a softwood or a hardwood, but a softwood is more preferable. In terms of peelability at the time of film formation, a cotton linter is preferably used. The cellulose esters produced therefrom can be mixed appropriately or used alone.

For example, the ratio of cellulose ester derived from cotton linter: cellulose ester derived from wood pulp (softwood) to cellulose ester derived from wood pulp (hardwood) is 100: 0: 0, 90: 10: 0, 85: 15: 50: 0, 20: 80: 0, 10: 90: 0, 0: 100: 0, 0: 0: 100, 80:10:10, 85: 0:15, 40:30:30 .

In the present embodiment, the cellulose ester resin is prepared by adding 1 g to 20 ml of pure water (electric conductivity of 0.1 μS / cm or less, pH 6.8), stirring at 25 ° C. for 1 hour under a nitrogen atmosphere, It is preferable that the conductivity is 1 to 100 mu S / cm.

[Film production method]

As the production method of the film base material, a production method such as a general inflation method, a T-die method, a calendering method, a cutting method, a casting method, an emulsion method and a hot press method can be used. Is preferably used. In addition, the film base material (cellulose ester film) of the surface protective film is preferably formed by the solution softening film forming method in that it is necessary to localize the plasticizer in the thickness direction of the film. Hereinafter, a preferable production method of the film substrate will be described.

&Lt; Method for producing base material by solution casting method &

1) Dissolution Process

The dissolving step is a step of dissolving a thermoplastic resin, a heat-shrinkable material, and other additives in an organic solvent containing a good solvent for a thermoplastic resin in a melting furnace while stirring to form a dope. The positive solvent refers to an organic solvent having a good solubility in a thermoplastic resin in the process for producing an optical film by a solution casting film forming method and exhibits a main effect on dissolution and an organic solvent used in a large amount thereof (Organic) solvent or the main (organic) solvent.

The dissolution of the thermoplastic resin can be carried out by a method at ordinary pressure, a method at a temperature not higher than the boiling point of the main solvent, a method by pressure at a temperature higher than the boiling point of the main solvent, JP-A-9-95544, JP-A-9-95557 , A method of performing a cooling dissolution method as disclosed in Japanese Patent Application Laid-Open No. 9-95538, and a method of operating at a high pressure as described in JP-A-11-21379 can be used. Is preferably carried out by pressurization at a boiling point or higher.

The recovered scrap is also reused. Recovered scraps are produced by finely pulverizing a film. The recovered scraps are produced by cutting out both side portions of a film, which are generated when a film is formed, and are spun out.

2) Flexible process

The fusing step is a step of transferring the dope to a pressure die through a delivery pump (for example, a pressurized metering gear pump) and transferring the endless endless belt, for example, a stainless steel belt or a rotating metal drum Is a process of softening the dope from the pressure die slit at the flexible position on the metal support.

It is preferable to use a press die which can adjust the slit shape of the crotch member portion of the die and make the film thickness uniform. The pressure die includes a coating hanger die and a T die, all of which are preferably used. The surface of the metal support is mirror-finished. Two or more pressure dies may be provided on the metal support in order to increase the film forming speed, and the doping amount may be divided into two or more layers. Alternatively, it is also preferable to obtain a laminated structure film by a covalent bonding method in which a plurality of doughs are simultaneously flexible.

3) Solvent evaporation process

The solvent evaporation step is a step of heating a web (a dope formed by softening a dope on a flexible support) on a flexible support to evaporate the solvent.

In order to evaporate the solvent, there are a method of blowing air from the web side and / or a method of transferring heat from the back side of the support by liquid, and a method of transferring heat from the front and rear sides by radiant heat. . A method of combining them is also preferably used. It is preferable to dry the web on the supporter after the softening on the support in an atmosphere of 40 to 100 캜. In order to maintain the atmosphere at 40 to 100 占 폚, it is preferable that hot air at this temperature is brought into contact with the upper surface of the web or heated by means of infrared rays or the like.

From the standpoint of surface quality, moisture permeability and releasability, it is preferable to peel the web from the support within 30 to 120 seconds.

4) Peeling process

The peeling step is a step of peeling the web from which the solvent has evaporated on the metal support at the peeling position. The peeled web is sent to the next process.

The temperature at the peeling position on the metal support is preferably 10 to 40 占 폚, more preferably 11 to 30 占 폚.

The amount of the residual solvent at the time of peeling the web on the metal support at the time of peeling is preferably in the range of 50 to 120 mass% depending on the strength of the drying condition, the length of the metal support, etc. However, When the web is peeled off at many points of time, if the web is too soft, the flatness is deteriorated in peeling, and peeling tension or vertical stripes tend to occur due to the peeling tension, so that the amount of residual solvent at the time of peeling is determined in balance of economic speed and quality.

The amount of residual solvent in the web is defined by the following equation.

Residual solvent amount (%) = (mass before heat treatment of web-mass after heat treatment of web) / (mass after heat treatment of web) 占 100

The heat treatment at the time of measuring the residual solvent amount means that the heat treatment is performed at 115 캜 for one hour.

The peel tension when peeling the film from the metal support is usually 196 to 245 N / m. It is preferable to peel off with a tensile force of 190 N / m or less in the case where wrinkles are likely to enter at the time of peeling, and further, it is preferable to peel at a minimum tensile force of 166.6 N / m, However, it is particularly preferable to peel off at a minimum tension of 100 N / m.

In the present embodiment, the temperature at the peeling position on the metal support is preferably -50 to 40 占 폚, more preferably 10 to 40 占 폚, and most preferably 15 to 30 占 폚.

5) Drying and drawing process

The drying and drawing processes are carried out by drying the web using a drying device for transferring the web by alternately passing it through a plurality of rolls arranged in a drying device after peeling and / or a tenter stretching device for clipping both ends of the web with a clip .

The drying means generally blows hot air on both sides of the web, but there is also a means of heating the microwave in place of the wind. Excessively rapid drying tends to impair the planarity of the finished film. Drying at a high temperature is preferably carried out at a residual solvent of about 8 mass% or less. And the drying is carried out at approximately 40 to 250 ° C. Particularly preferably 40 to 160 캜.

When the tenter stretching device is used, it is preferable to use a device capable of independently controlling the gripping length of the film (the distance from the start of gripping to the end of gripping) by the left and right gripping means of the tenter. Further, in the tentering process, it is also preferable to make the compartments having intentionally different temperatures in order to improve the planarity.

It is also preferable to provide a neutral zone so that the respective compartments do not cause interference between different temperature zones.

In addition, the stretching operation may be divided into multiple steps, or biaxial stretching in the machine direction and width direction is also preferable. In the case of biaxial stretching, simultaneous biaxial stretching may be performed, or may be performed stepwise.

In this case, the stepwise means that, for example, the stretching in different stretching directions can be sequentially performed, the stretching in the same direction can be divided into multiple steps, and the stretching in different directions can be added to any one of the steps. That is, for example, the following stretching step is also possible.

a) Stretching in the flexible direction - Stretching in the width direction - Stretching in the flexible direction - Stretching in the flexible direction

b) Drawing in the width direction - Drawing in the width direction - Drawing in the draw direction - Drawing in the draw direction

The simultaneous biaxial stretching may include stretching in one direction and shrinking the other by relaxing the tension. The preferred stretching magnification of the simultaneous biaxial stretching may be in the range of 1.01 times to 1.5 times in both the width direction and the longitudinal direction.

The amount of the residual solvent in the web when stretching is preferably 20 to 100 mass% at the start of the stretching, and it is preferable to perform drying while stretching until the amount of residual solvent in the web becomes 10 mass% or less By mass, more preferably 5% by mass or less.

The drying temperature in the case of stretching is preferably 30 to 160 ° C, more preferably 50 to 150 ° C, and most preferably 70 to 140 ° C.

In the stretching step, the temperature distribution in the width direction of the atmosphere is preferably small from the viewpoint of enhancing the uniformity of the film, and the temperature distribution in the width direction in the stretching step is preferably within ± 5 ° C, And most preferably within ± 1 ° C.

6) Winding process

The winding step is a step in which the amount of the residual solvent in the web becomes 2% by mass or less, and then the film is wound as a film by a winding machine. When the residual solvent amount is 0.4% by mass or less, a film having good dimensional stability can be obtained. Particularly preferably from 0.00 to 0.10% by mass.

As the winding method, a generally used one may be used. Examples of the winding method include a constant torque method, a constant tension method, a taper tension method, an internal stress constant program tension control method, and the like.

The protective film according to the present embodiment is preferably a long film, specifically about 100 m to 5000 m, and is usually provided in a roll form. Further, the width of the film is preferably 1.3 to 4 m, more preferably 1.4 to 2 m.

&Lt; Process for producing base material by melt blown film forming method &

Next, a method for producing the backside protective film by the melt soft-film forming method will be described.

&Lt; Melt Pellet Manufacturing Process >

The composition containing the resin used for melt extrusion is usually kneaded and pelletized in advance.

For example, an additive containing a dry thermoplastic resin and a heat-shrinkable material may be pelletized into an extruder, kneaded using a single-screw or twin-screw extruder, extruded from the die into a strand shape, And then pelletized by water-cooling or air-cooling and cutting.

Drying the raw material before extrusion is important in preventing the decomposition of the raw materials. Particularly, since cellulose esters are easily hygroscopic, they are preferably dried at 70 to 140 캜 for 3 hours or more with a dehumidifying hot air dryer or a vacuum dryer, and the water content is preferably 200 ppm or less and 100 ppm or less.

The additives may be mixed before being supplied to the extruder, or they may be supplied to individual feeders. In addition, small amounts of additives such as particles and antioxidants are mixed uniformly, so that it is preferable to mix them in advance.

The antioxidant may be mixed with solids, and if necessary, the antioxidant may be dissolved in a solvent, impregnated with a thermoplastic resin and mixed, or may be mixed by spraying.

It is preferable to use a vacuum Nauta mixer or the like in order to simultaneously perform drying and mixing. Further, in the case of coming into contact with air such as the outlet from the feeder unit or the die, it is preferable to set it in an atmosphere of dehumidified air or dehumidified N ₂ gas.

The extruder can be pelletized so that the shearing force is suppressed and the resin is not deteriorated (decrease in molecular weight, coloring, gel formation, etc.), and it is preferable to process the extruder at a low temperature as possible. For example, in the case of a twin-screw extruder, it is preferable to use a deep groove-type screw to rotate in the same direction. From the uniformity of kneading, occlusal type is preferable.

Film formation is carried out using the pellets obtained as described above. It is also possible to feed the powder of the raw material directly to the extruder by using a feeder and to form the film as it is without pelletizing.

&Lt; Process of extruding molten mixture from a die with a cooling roll >

First, the produced pellets are filtered using a single-screw extruder or a twin-screw extruder at a melt temperature (Tm) at the time of extrusion of about 200 to 300 ° C to remove impurities, Extruded in a film form from a T die, solidified on a cooling roll, and pressed while pressing with the elastic touch roll. Tm is the temperature at the die exit of the extruder.

When introduced into the extruder from the feed hopper, it is preferable to prevent the oxidative decomposition or the like under vacuum or under reduced pressure or in an inert gas atmosphere.

If foreign matter such as flaws or condensation of a plasticizer adheres to the die, a stripe-like defect may occur. Such a defect is also referred to as a die line. However, in order to reduce defects on the surface of a die line or the like, it is preferable that the pipe from the extruder to the die has a structure in which the retention portion of the resin is minimized. It is preferable to use the die having no internal scratches or the like as much as possible.

It is preferable that the inner surface contacting the molten resin such as an extruder or a die is subjected to a surface treatment in which the surface roughness is reduced or a material having a low surface energy is used so that the molten resin is hardly adhered thereto. Specifically, it may be hard chrome plated or ceramic sprayed and polished so that the surface roughness is 0.2 S or less.

The cooling roll is not particularly limited, but may be a roll having a structure in which a temperature-controllable heating medium or a refrigerant flows in a high-rigidity metal roll. The size of the cooling roll is not limited, but it may be of a size sufficient to cool the melt extruded film, and usually the diameter of the cooling roll is about 100 mm to 1 m.

The material of the surface of the cooling roll is carbon steel, stainless steel, aluminum, titanium and the like. It is preferable to perform surface treatment such as hard chrome plating, nickel plating, amorphous chromium plating, or ceramic spraying in order to increase the hardness of the surface or improve the peelability with the resin.

The surface roughness of the surface of the cooling roll is preferably 0.1 mu m or less in terms of Ra, and more preferably 0.05 mu m or less. The smoother the roll surface, the smoother the surface of the resulting film. Of course, it is preferable that the surface-finished surface is further polished to the above-described surface roughness.

Examples of the elastic touch rolls include those disclosed in JP-A-03-124425, JP-A-08-224772, JP-A-07-100960, JP-A-10-272676, WO97 / 028950, 11-235747, 2002-36332, 2005-172940 and 2005-280217 disclose a silicone rubber roll whose surface is coated with a thin metal film, Can be used.

When the film is peeled from the cooling roll, it is preferable to control the tension to prevent deformation of the film.

 [Process for producing composite resin film]

The film base material of the present embodiment can be composed of a composite resin film. The composite resin film can be produced by a production method having a film-forming step by a co-extrusion method.

&Lt; Coextrusion method &

In this embodiment, a film having a laminated structure can be produced by a co-extrusion method. For example, a film having a constitution of a skin layer / a core layer / a skin layer can be produced. For example, the matting agent can be contained in the skin layer only, or only in the skin layer. The plasticizer and ultraviolet absorber may be contained in the core layer more than the skin layer, or may be incorporated only in the core layer. The plasticizer and the ultraviolet absorber may be changed in the core layer and the skin layer. For example, a low-volatility plasticizer and / or an ultraviolet absorber may be contained in the skin layer so that a plasticizer having excellent plasticity or an ultraviolet absorptive This excellent ultraviolet absorber may be added. The glass transition temperature of the skin layer and the core layer may be different from each other and the glass transition temperature of the core layer is preferably lower than the glass transition temperature of the skin layer. At this time, the glass transition temperature of both the skin and the core may be measured, and an average value calculated from these volume fractions may be defined as the glass transition temperature (Tg) and treated in the same manner. The viscosity of the melt containing the cellulose ester at the time of melt refining may also be different in the skin layer and the core layer, or may be the viscosity of the skin layer> the viscosity of the core layer, or the viscosity of the core layer and the viscosity of the skin layer.

The co-extrusion method is a method in which a plurality of extruders are used to heat and melt a resin to be laminated from each of the extruders, coalesce the respective resins, co-extrude from a slit-shaped discharge port of a T-die, Thereby forming a cast sheet (unstretched state). As a method of joining the molten resin and extruding the sheet from the T die, there are a feed block method in which the molten resin is merged and then the manifold is expanded, and a multi-manifold method in which the molten resin is expanded in the respective manifolds, Either of them may be used.

 〔additive〕

(Antioxidant)

The film substrate preferably contains an antioxidant as an additive. A preferred antioxidant is phosphorous or phenol-based, and it is more preferable to combine phosphorus and phenol at the same time. Hereinafter, the antioxidant that can be suitably used in the present embodiment will be described.

&Lt; Phenolic antioxidant >

In the present embodiment, a phenolic antioxidant is preferably used, and a hindered phenol compound is particularly preferably used.

<Phosphorus antioxidant>

Phosphorus compounds such as phosphite, phosphonite, phosphinite, or tertiary phosphane can be used as the phosphorus antioxidant. As the phosphorus compound, conventionally known compounds can be used. For example, Japanese Patent Application Laid-Open Nos. 2002-138188 and 2005-344044, paragraphs (0022) to (0027), Japanese Patent Application Laid-Open No. 2004-182979, paragraphs (0023) Japanese Patent Application Laid-Open Nos. 10-306175, 1-254744, 2-270892, 5-202078, 5-178870, 2004- 504435, Japanese Patent Publication No. 2004-530759 and Japanese Patent Application No. 2005-353229 described in the specification of each publication.

The addition amount of the phosphorus compound is usually 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass based on 100 parts by mass of the resin.

(Other antioxidants)

In addition, it is also possible to use, for example, dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, pentaerythrityl (3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenylacrylate, 2-tert- butyl- Heat-resistant processing stabilizers such as 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl) ethyl] -4,6-di-tert- pentylphenyl acrylate, 3,4-dihydro-2H-1-benzopyran compounds, 3,3'-spirodicroman compounds, 1,1-spiroin compound, morpholine, thiomorpholine, thiomorpholine oxime, An oxygen scavenger such as a thiomorpholine dioxide, a compound having a piperazine skeleton in a partial structure, and a dialkoxybenzene compound described in JP-A-03-174150. The partial structure of these antioxidants may be part of the polymer or regularly pendant to the polymer and may be introduced into a part of the molecular structure of an additive such as a plasticizer, an acid scavenger, or an ultraviolet absorber.

(Other additives)

The film base according to the present embodiment may contain, in addition to the above-mentioned compounds, a variety of compounds depending on the purpose as additives.

<Acid captive agent>

As the acid capturing agent, it is preferable to include an epoxy compound as an acid capturing agent described in U.S. Patent No. 4,137,201. Epoxy compounds as such acid scavengers are known in the art and include diglycidyl ethers of various polyglycols, especially polyglycols derived by condensation such as about 8 to 40 moles of ethylene oxide per mole of polyglycol, (For example, those conventionally used together with a vinyl chloride polymer composition and a vinyl chloride polymer composition), epoxidized ether condensation products, diglycidyl ether of bisphenol A Glycidyl ethers (i.e., 4,4'-dihydroxydiphenyldimethylmethane), epoxidized unsaturated fatty acid esters (in particular, alkyl esters of about 4 to 2 carbon atoms of fatty acids of 2 to 22 carbon atoms For example, butyl epoxystearate), and various epoxidized long chain fatty acid triglycerides (e.g., epoxidized soybean oil, etc.) Epoxidized vegetable oils and other unsaturated natural oils, which are sometimes referred to as epoxidized natural glycerides or unsaturated fatty acids, these fatty acids generally containing 12 to 22 carbon atoms do.

<Photon tablets>

Examples of the light stabilizer include hindered amine light stabilizer (HALS) compounds, which are known compounds, such as those described in U.S. Patent No. 4,619,956, Columns 5 to 11, and U.S. Patent No. 4,839,405 As described in columns 3 to 5, 2,2,6,6-tetraalkylpiperidine compounds, their acid addition salts, or their complexes with metal compounds are included. Further, a light stabilizer described in JP-A No. 2007-63311 can be used.

<Ultraviolet absorber>

From the viewpoint of prevention of deterioration due to ultraviolet rays, the ultraviolet absorber preferably has an excellent ultraviolet ray absorbing ability at a wavelength of 370 nm or less and a small amount of visible light absorption at a wavelength of 400 nm or more from the viewpoint of liquid crystal display property. For example, an oxibenzophenone-based compound, a benzotriazole-based compound, a salicylic acid ester-based compound, a benzophenone-based compound, a cyanoacrylate-based compound, a nickel complex salt compound, Benzotriazole-based compounds are preferable. The ultraviolet absorber described in JP-A-10-182621, JP-A-8-337574, and JP-A-6-148430 may be used.

In the present embodiment, the ultraviolet absorber is preferably added in an amount of 0.1 to 20 mass%, more preferably 0.5 to 10 mass%, further preferably 1 to 5 mass%. These may be used in combination of two or more.

<Mat>

In the film base of the present embodiment, fine particles such as a matting agent can be added, and as the fine particles, there can be mentioned fine particles of an inorganic compound or fine particles of an organic compound. Examples of the fine particles include inorganic fine particles such as silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, kaolin, talc, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate, . Among them, silicon dioxide is preferable because the haze of the resin substrate can be lowered. Fine particles such as silicon dioxide are often surface-treated with an organic material, but this is preferable because it can lower the haze of the resin substrate.

<Plasticizer>

In the cellulose ester film, a plasticizer may be used in combination to improve the moisture permeability, fluidity of the composition and flexibility of the film. Examples of the plasticizer include phthalic acid ester, fatty acid ester, trimellitic acid ester, phosphate ester, polyester, sugar ester, and acrylic polymer. Among these, a plasticizer of a polyester-based or sugar ester-based polymer is preferably used from the viewpoint of moisture permeability.

These plasticizers are preferably added in an amount of 0.5 to 30 parts by mass based on 100 parts by mass of the cellulose ester film.

[Hard Coating Layer]

A hard coat layer may be formed on the surface of the surface protective film (film base material 4a) for the purpose of surface protection. The hard coating layer is preferably composed of, for example, an active energy ray-curable resin.

(Active energy ray-curable resin)

The active energy ray-curable resin refers to a resin that is cured through a crosslinking reaction or the like by irradiation with actinic rays such as ultraviolet rays or electron beams, and specifically a resin having an ethylenic unsaturated group. More specifically, an ultraviolet curable urethane acrylate resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxyacrylate resin, an ultraviolet curable polyol acrylate resin, or an ultraviolet curable epoxy resin is preferably used. Among them, an ultraviolet curable acrylate resin is preferable.

As the ultraviolet curable acrylate resin, polyfunctional acrylate is preferable. The polyfunctional acrylate is preferably selected from the group consisting of pentaerythritol polyfunctional acrylate, dipentaerythritol polyfunctional acrylate, pentaerythritol polyfunctional methacrylate and dipentaerythritol polyfunctional methacrylate Do. Here, the polyfunctional acrylate is a compound having two or more acryloyloxy groups or methacryloyl groups in the molecule.

The blending amount of the active energy ray-curable resin in the hard coat layer composition is usually 10 to 99 parts by mass, preferably 35 to 99 parts by mass, when 100 parts by mass of the whole composition is used. When the compounding amount of the active energy ray-curable resin is small, it is difficult to sufficiently obtain the film strength of the hard coat layer. In addition, when the amount is too large, it is not preferable because film thickness uniformity, coating streaks, and the like are caused when coating is performed by a known coating method, which will be described later.

(Cationic polymerizable compound)

The hard coat layer may also contain a cationic polymerizable compound. The cationic polymerizable compound is a resin which is subjected to energy active ray irradiation or cationic polymerization by heat. Specific examples thereof include an epoxy group, a cyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiroorthoester compound, and a vinyloxo group. Among them, a compound having a functional group such as an epoxy group or a vinyl ether group is suitably used in the present embodiment.

When the cationic polymerizable compound is contained in the hard coat layer composition, the amount of the cationic polymerizable compound in the hard coat layer composition is usually 1 to 90 parts by mass, preferably 1 to 50 parts by mass, Mass part.

(Fine particles)

The hard coating layer may contain fine particles. Examples of the fine particles include inorganic fine particles and organic fine particles. Examples of the inorganic particles include inorganic particles such as silica, titanium oxide, aluminum oxide, tin oxide, indium oxide, ITO, zinc oxide, zirconium oxide, magnesium oxide, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, Magnesium silicate and calcium phosphate. Examples of the organic particles include polymethacrylic acid methyl acrylate resin powder, acryl styrene resin powder, polymethyl methacrylate resin powder, silicone resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder , A melamine resin powder, a polyolefin resin powder, a polyester resin powder, a polyamide resin powder, a polyimide resin powder or a polyfluorinated ethylene resin powder. The average particle diameter of these fine particles is preferably 30 nm to 200 nm in view of the stability and clearability of the hard coat layer coating composition. The hard coat layer may contain two or more kinds of fine particles having different particle diameters. From the viewpoint of achieving a desired pencil hardness, it is preferable that the hard coat layer contains silica fine particles.

It is preferable that the hard coat layer contains the reactive silica fine particles (Xa) surface-treated with an organic compound having a polymerizable unsaturated group in order to more exert the action and effect of the present embodiment.

The hard coating layer preferably contains the above-mentioned active energy ray-curable resin and fine particles and has a mass ratio of active energy ray-curable resin: fine particles of 90:10 to 20:80.

(Other additives, method for producing hard coat layer)

The hard coat layer preferably contains a photopolymerization initiator for accelerating curing of the active energy ray curable resin. The blending amount of the photopolymerization initiator is preferably from 20: 100 to 0.01: 100 as a photopolymerization initiator: active energy ray curable resin in a mass ratio.

Specific examples of the photopolymerization initiator include alkylphenone, acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone,? -Amyloxime ester, thioxanthone, and derivatives thereof. It does not. Those commercially available may be used. For example, IRGACURE 184, IRGACURE 907, IRGACURE 651, and the like manufactured by BASF Japan Co., Ltd. can be mentioned as preferable examples.

The hard coat layer may contain the same ultraviolet absorber as the above ultraviolet absorber.

It is preferable that the hard coating layer is composed of two or more layers and that the ultraviolet absorber is contained in the hard coating layer in contact with the film base material in order to exert the desired effect of the present embodiment and to improve the film strength (scratch resistance) It is preferable in that the pencil hardness can be satisfactorily obtained. The content of the ultraviolet absorber is preferably in the range of 0.01: 100 to 10: 100 as the mass ratio of the ultraviolet absorber: hard coat layer composition.

When two or more hard coating layers are provided, the film thickness of the hard coating layer in contact with the film substrate is preferably in the range of 0.05 to 2 mu m. The lamination of two or more layers may be formed as a simultaneous middle layer. The co-intermediate layer means that two or more hard coat layers are applied on a substrate by wet on wet without a drying step to form a hard coat layer. In order to laminate the second hard coating layer wet on wet without the drying process on the first hard coat layer, it may be carried out in the order of the extrusion coater or in the simultaneous middle layer with the slot die having the plurality of slits.

As a method for producing the hard coat layer, there is a method in which a hard coat layer coating composition diluted with a solvent capable of swelling or partially dissolving a cellulose ester film is coated on a cellulose ester film by the following method, dried and cured, It is preferable in that it is easy to obtain interlayer adhesion between the coating layer and the cellulose ester film.

As the solvent which swells or partially dissolves the cellulose ester film, a solvent containing a ketone and / or an acetic acid ester is preferable. Specific examples of the ketone include methyl ethyl ketone, acetone, and cyclohexanone. Examples of the acetic acid ester include ethyl acetate, methyl acetate, and butyl acetate. The hard coat layer coating composition may contain, as other solvent, an alcohol-based solvent.

The coating amount of the hard coat layer coating composition is preferably from 0.1 to 40 탆 in wet film thickness, more preferably from 0.5 to 30 탆. The dry film thickness is preferably about 5 to 20 占 퐉, more preferably 7 to 12 占 퐉 in average film thickness.

The hard coating layer may be formed by applying a hard coat coating composition for forming a hard coat layer using a known coating method such as a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die (extrusion) , Dried, irradiated with active rays (also referred to as UV curing treatment), and, if necessary, subjected to a heat treatment after UV curing. The heat treatment temperature after UV curing is preferably 80 DEG C or higher, more preferably 100 DEG C or higher, and particularly preferably 120 DEG C or higher. By performing the heat treatment after UV curing at such a high temperature, the mechanical strength (scratch resistance, pencil hardness) of the hard coat layer becomes better.

<Functional layer>

In the hard coating film of the present embodiment, a functional layer such as a back coating layer, an antireflection layer, and an antiglare layer may be formed in addition to the hard coating layer.

(Back coating layer)

A back coating layer may be formed on the surface of the cellulose ester film of the present embodiment opposite to the side where the hard coat layer is formed to prevent curling or blocking.

From the viewpoint of preventing curling or blocking, it is preferable that the back coating layer contains at least one selected from the group consisting of silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, talc, clay, fired kaolin, calcined calcium silicate, tin oxide, Particles of calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate may be added.

The content of the particles contained in the back coating layer is preferably from 0.1 to 50 mass% with respect to the binder. The haze increase when the back coating layer is provided is preferably 0.5% or less, and more preferably 0.1% or less. As the binder, a cellulose ester resin is preferable. The coating composition for forming the back coating layer preferably contains a solvent for alcohols, ketones and / or acetic acid esters.

(Antireflection layer)

The hard coating film of the present embodiment may be used as an antireflection film having a function of preventing reflection of external light by providing an antireflection layer on the upper layer of the hard coat layer.

It is preferable that the antireflection layer is laminated in consideration of the refractive index, the film thickness, the number of layers, the layer order, and the like so that the reflectance is reduced by optical interference. It is preferable that the antireflection layer is formed by combining a low refractive index layer having a refractive index lower than that of the film base supporting the support or a high refractive index layer and a low refractive index layer having a higher refractive index than the support. Particularly preferably, three antireflection layers composed of three or more refractive index layers and having different refractive indices from the support side are used as the intermediate refractive index layer (a layer having a higher refractive index than the support and a refractive index lower than that of the high refractive index layer) / a high refractive index layer / Low refractive index layer are preferably laminated in this order. Alternatively, an antireflection layer having a layer structure of four or more layers in which two or more high refractive index layers and two or more low refractive index layers are alternately laminated is also preferably used.

As the layer structure of the film having the antireflection layer, the following structure is conceivable, but the present invention is not limited thereto.

Cellulose acetate film / hard coat layer / low refractive index layer

Cellulose acetate film / hard coat layer / medium refractive index layer / low refractive index layer

Cellulose acetate film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer

Cellulose acetate film / hard coat layer / high refractive index layer (conductive layer) / low refractive index layer

Cellulose acetate film / hard coat layer / antiglare layer / low refractive index layer

(Low refractive index layer)

The low refractive index layer preferably contains silica-based fine particles, and the refractive index thereof is preferably in the range of 1.30 to 1.45 at a temperature of 23 캜 and a wavelength of 550 nm.

The film thickness of the low refractive index layer is preferably from 5 nm to 0.5 占 퐉, more preferably from 10 nm to 0.3 占 퐉, and most preferably from 30 nm to 0.2 占 퐉.

(High refractive index layer)

The refractive index of the high refractive index layer is preferably adjusted in the range of 1.4 to 2.2 in the measurement of the wavelength of 550 nm at 23 캜. The thickness of the high refractive index layer is preferably from 5 nm to 1 탆, more preferably from 10 nm to 0.2 탆, and most preferably from 30 nm to 0.1 탆. The adjustment of the refractive index can be performed by adding metal oxide fine particles or the like. The refractive index of the metal oxide fine particles to be used is preferably 1.80 to 2.60, more preferably 1.85 to 2.50.

(Emulsion layer)

On the hard coat layer, an antiglare layer may be formed as a functional layer. The antiglare layer lowers the visibility of the reflected image by looking at the outline of the image reflected on the surface of the film so that when the image display device such as a liquid crystal display, an organic EL display, or a plasma display is used, to be. Specifically, the antiglare layer is a layer in which the arithmetic mean roughness (Ra) of the layer surface is adjusted to 0.1 to 1 탆 by adding fine particles or the like to the hard coat layer described above or by pressing the mold to form protrusions on the surface .

[Pressure-sensitive adhesive layer]

As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer (corresponding to the pressure-sensitive adhesive layer 30 in Fig. 1) used for adhering the touch panel to the display device, known pressure-sensitive adhesives can be used without any particular limitation. Examples thereof include acrylic pressure- Based pressure-sensitive adhesives, urethane pressure-sensitive adhesives, rubber pressure-sensitive adhesives, polyester pressure-sensitive adhesives and the like can be used, but acrylic pressure-sensitive adhesives having a relatively easy control of adhesive force and storage elastic modulus are particularly preferable.

Examples of the acrylic pressure-sensitive adhesive include acrylic pressure-sensitive adhesives such as methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, Acrylic acid alkyl esters having 1 to 20 carbon atoms such as 2-ethylhexyl acrylate, isooctyl (meth) acrylate and decyl (meth) acrylate, and (meth) acrylic acid, Based crosslinking agent, an epoxy-based crosslinking agent, an aziridine-based crosslinking agent, an isocyanurate-based crosslinking agent, an isocyanurate-based crosslinking agent, an isocyanurate-based crosslinking agent, , A metal chelating crosslinking agent, and the like.

The thickness of the pressure-sensitive adhesive layer is preferably 1 占 퐉 to 13 占 퐉. When the thickness of the pressure-sensitive adhesive layer is 1 占 퐉 or more, a sufficient adhesive force can be obtained. When the thickness of the pressure-sensitive adhesive layer is 13 占 퐉 or less, the adhesive can be prevented from being pushed out during punching processing or cutting processing, and high pencil hardness is maintained. The preferable thickness of the pressure-sensitive adhesive layer is 3 to 12 占 퐉.

The storage elastic modulus of the pressure-sensitive adhesive layer is preferably 1.0 x 10 ⁶ to 1.0 x 10 ⁸ Pa at 0 ° C. If the storage modulus of the pressure-sensitive adhesive layer greater than 1.0 × 10 ⁶ Pa, it is possible to obtain a sufficient punching processability, cutting processability and high pencil hardness, 1.0 × 10 ⁸ Pa or less, it is possible to obtain a sufficient adhesive strength. The preferred storage modulus of the pressure-sensitive adhesive layer is 1.5 × 10 ⁶ to 1.0 × 10 ⁷ Pa.

As a method of forming a pressure-sensitive adhesive layer on a film, there is a method of laminating a film on a pressure-sensitive adhesive layer produced by applying a pressure-sensitive adhesive composition on a release sheet and drying. Examples of the method of applying the pressure-sensitive adhesive composition include conventionally known methods such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method and a curtain coating method have. Further, the pressure-sensitive adhesive composition may be laminated directly by applying the pressure-sensitive adhesive composition on the surface of the film and drying the pressure-sensitive adhesive composition.

The above release sheet can use various release sheets, but it is typically composed of a base sheet having a releasable surface. Examples of the base sheet include films such as polyester resins, polyethylene resins, polypropylene resins, polystyrene resins and polycarbonate resins, and films and synthetic paper in which these films are filled with fillers such as transfer agents. In addition, paper substrates such as gloss paper, clay coat paper, and top paper can be mentioned.

In order to have releasability on the surface of the substrate sheet, a releasing agent such as a thermosetting silicone resin or an ultraviolet-curing silicone resin may be applied to the surface of the substrate sheet by application or the like. The coating amount of the releasing agent is preferably 0.03 to 3.0 g / m ² . The release sheet is laminated on the surface having the release agent in contact with the pressure-sensitive adhesive layer.

[Shatterproof Film]

The scattering prevention film 25 is provided on the electrode layer (electrode pattern 22) in order to prevent scattering of the glass substrate 21 due to external impact or the like. In the present embodiment, the scattering-prevention film 25 is made of a cellulose ester film having a thickness of 20 to 66 μm.

Examples of the cellulose ester resin usable for the shrinkage prevention film 25 include a cellulose ester resin usable for the above-mentioned protective film (film base 4a).

As such a cellulose ester film, a film having a retardation (Ro) in the in-plane direction of 0 nm to 10 nm can be preferably used. In this case, since the interference due to the in-plane retardation is small, the visibility of the display panel 10 visually through the touch panel 20 can be improved. When a film having a retardation (Ro) in the in-plane direction of 0 nm to 10 nm is used, cellulose ester having a total acyl substitution degree of 2.6 or more is preferably used, and cellulose acetate (cellulose triacetate) having a total acyl substitution degree of 2.6 or more And is more preferably used.

The cellulose ester film of the shrinkage preventing film 25 may be a film having a retardation Ro of 30 nm to 200 nm in the in plane direction and may be a film having a slow axis of the shatterproof film 10 DEG to 80 DEG. With this configuration, since the linearly polarized light transmitted through the polarizer 3 can be changed to elliptically polarized light or circularly polarized light, it is possible to improve the visibility when viewing the display device 10 by using polarized sunglasses. When a film having a retardation (Ro) of 30 nm to 200 nm is used, cellulose ester having a total acyl substitution degree of less than 2.6 is preferably used, and cellulose acetate (cellulose diacetate) having a total acyl substitution degree of less than 2.6 is more preferably used .

[Conductive layer]

A conductive layer (corresponding to the conductive layer 26 in Fig. 1) as an electromagnetic wave shielding layer formed on the shrinkage preventing film is a layer containing at least a conductive substance and containing a binder, a photosensitive compound, .

[Conductive material]

The structure of the conductive material is not particularly limited and may be appropriately selected in accordance with the intended use. It is preferable that the conductive material contains fibers of either a solid structure or a hollow structure or a conductive polymer.

Here, a fiber having a solid structure may be referred to as a wire, and a fiber having a hollow structure may be referred to as a tube.

The conductive fiber having an average short axis length of 5 nm to 1,000 nm and an average major axis length of 1 탆 to 100 탆 is sometimes referred to as &quot; nanowire &quot;.

In addition, the average short axis length is 1 nm to 1,000 nm, and the average major axis length is 0.1 to 1,000 μm, and the conductive fiber having a hollow structure is sometimes called "nanotube".

The material of the conductive material is not particularly limited as long as it has conductivity, and may be appropriately selected according to the purpose, but it is preferably at least one of metal and carbon. Among them, the conductive fiber is preferably at least one of metal nanowires, metal nanotubes, and carbon nanotubes.

<Metal nanowire>

The material of the metal nanowire is not particularly limited and may be appropriately selected depending on the purpose. For example, at least one kind of metal selected from the group consisting of the fourth period, the fifth period and the sixth period of the long periodic table (IUPAC1991) is preferable, and at least one kind of metal selected from the groups 2 to 14 And still more preferably at least one metal selected from Groups 2, 8, 9, 10, 11, 12, 13, and 14, Is particularly preferable.

Examples of the metal include copper, silver, gold, platinum, palladium, nickel, tin, cobalt, rhodium, iridium, iron, ruthenium, osmium, manganese, molybdenum, tungsten, niobium, tantalum, titanium, bismuth, antimony, Lead, or an alloy thereof. Of these, an alloy of silver and silver is preferable from the viewpoint of excellent conductivity.

Examples of the metal used as the alloy with silver include platinum, osmium, palladium, iridium and the like. These may be used alone, or two or more kinds may be used in combination.

The shape of the metal nanowires is not particularly limited and can be appropriately selected depending on the purpose. For example, any shape such as a columnar shape, a rectangular parallelepiped shape, a columnar shape having a polygonal cross section, and the like can be adopted. In applications where high transparency is required, it is preferable that the cross-sectional shape is a cylindrical shape or a polygonal cross-section is rounded. The cross-sectional shape of the metal nanowires can be examined by applying a dispersion of aqueous metal nanowires on a substrate and observing the cross section with a transmission electron microscope (TEM).

The average short axis length (sometimes referred to as "average minor axis diameter", "average diameter") of the metal nanowires is preferably 1 nm to 50 nm. If the average short axis length is less than 1 nm, the oxidation resistance tends to deteriorate and the durability tends to deteriorate. When the average short axis length is more than 50 nm, scattering due to the metal nanowire may occur and sufficient transparency may not be obtained. The average short axis length is more preferably from 10 nm to 40 nm, and further preferably from 15 nm to 35 nm.

The average shortening length of the metal nanowires was measured by observing 300 metal nanowires using a transmission electron microscope (TEM (JEM-2000FX, manufactured by Nihon Denshi Co., Ltd.)) and calculating the average shortening length . When the short axis of the metal nanowire is not circular, the shortest length is the longest one.

The average major axis length (sometimes referred to as "average length") of the metal nanowires is preferably 1 μm to 40 μm. If the average major axis length is less than 1 mu m, it is difficult to form an intimate network, and sufficient conductivity may not be obtained. When the average major axis length is more than 40 mu m, metal nanowires are too long to be entangled at the time of manufacture, May occur. The average major axis length is more preferably 3 탆 to 35 탆, and further preferably 5 탆 to 30 탆.

The average major axis length of the metal nanowires can be measured by observing 300 metal nanowires using, for example, a transmission electron microscope (TEM; JEM-2000FX, manufactured by Nihon Denshi Co., Ltd.) The average long axis length is obtained. When the metal nanowire is curved, a value calculated from the radius and the curvature is taken as the long axis length in consideration of a circle making the circle.

As a method for producing metal nanowires, for example, Japanese Patent Laid-Open Nos. 2009-215594, 2009-242880, 2009-299162, 2010-84173 , The method described in Japanese Patent Application Laid-Open No. 2010-86714 can be used. The production method of the metal nanowires is not particularly limited and may be produced by any method, but it is preferable to produce the metal nanowires by heating them in a solvent in which a halogen compound and a dispersing additive are dissolved as described below.

<Metal nanotubes>

The material of the metal nanotube is not particularly limited and may be any metal. For example, the material of the metal nanowire described above can be used.

The shape of the metal nanotubes may be a single layer or a multilayer, but is preferably a single layer in that it is excellent in conductivity and thermal conductivity.

The thickness (difference between the outer diameter and the inner diameter) of the metal nanotube is preferably 3 nm to 80 nm. If the thickness is less than 3 nm, oxidation resistance may deteriorate and durability may deteriorate. If it exceeds 80 nm, scattering due to metal nanotubes may occur. It is more preferable that the thickness is 3 nm to 30 nm.

The average major axis length of the metal nanotubes is preferably 1 占 퐉 to 40 占 퐉, more preferably 3 占 퐉 to 35 占 퐉, and still more preferably 5 占 퐉 to 30 占 퐉.

The method for producing the metal nanotubes is not particularly limited and may be appropriately selected depending on the purpose. For example, the method described in U.S. Patent Application Publication No. 2005/0056118 and the like can be used.

<Carbon nanotube>

The carbon nanotube (CNT) is a material in which the graphitic carbon atomic surface (graphene sheet) is a single layer or a multilayered coaxial tube. Single-walled carbon nanotubes (SWNTs) are used for the single-walled carbon nanotubes. Multi-walled nanotubes (MWNTs) are used for the multi-walled carbon nanotubes, and carbon nanotubes for the two-walled carbon nanotubes are also referred to as double walled nanotubes (DWNTs). In the conductive fiber used in the present embodiment, the carbon nanotube may be a single layer or a multilayer, but is preferably a single layer in that it is excellent in conductivity and thermal conductivity.

The production method of the carbon nanotubes is not particularly limited and can be appropriately selected according to the purpose. For example, it is possible to use a HiPco (high-purity) method in which carbon dioxide is subjected to catalytic hydrogen reduction, arc discharge, laser evaporation, thermal CVD, plasma CVD, vapor phase growth, pressure carbon monoxide process) may be used.

The carbon nanotubes obtained by these methods can be obtained by removing the residues such as by-products and catalytic metals by a method such as washing, centrifugation, filtration, oxidation, chromatography, etc., It is preferable from the viewpoint that it can be obtained.

The aspect ratio of the conductive fibers is preferably 10 or more. The aspect ratio refers generally to the ratio of the long side to the short side (the ratio of the average major axis length to the average short axis length) of the fibrous substance.

The method of measuring the aspect ratio is not particularly limited and can be appropriately selected in accordance with the purpose, and examples thereof include a method of measuring by an electron microscope and the like.

When the aspect ratio of the conductive fiber is measured by an electron microscope, whether or not the aspect ratio of the conductive fiber is 10 or more can be confirmed only in one field of view of the electron microscope. Further, by measuring the long axis length and the short axis length of the conductive fiber separately, the aspect ratio of the entire conductive fiber can be estimated.

When the conductive fibers are in the form of a tube, the diameter of the tube for calculating the aspect ratio is used.

The aspect ratio of the conductive fiber is not particularly limited as long as it is 10 or more, and can be appropriately selected according to the purpose, but it is preferably 50 to 1,000,000. If the aspect ratio is less than 10, the network is not formed by the conductive fibers, and sufficient conductivity may not be obtained. On the other hand, if the aspect ratio is more than 1,000,000, conductive fibers are entangled before the formation of the conductive fibers, There is a case where a stable liquid can not be obtained. Further, the aspect ratio is more preferably 100 to 1,000,000.

The proportion of the conductive fibers having an aspect ratio of 10 or more in the whole conductive composition is preferably 50% or more by volume. If the ratio is less than 50%, the conductive material contributing to conductivity may be reduced to deteriorate the conductivity. In addition, since a close network can not be formed, voltage concentration may occur and durability may be deteriorated. Particles having a shape other than the conductive fibers are not preferable because they do not greatly contribute to the conductivity and have absorption. Particularly in the case of metals, when the absorption of plasmon such as spheres is strong, the transparency is deteriorated . The above ratio is more preferably 60% or more, and particularly preferably 75% or more.

In the case where the conductive fiber is a silver nanowire, for example, the silver nanowire aqueous dispersion is filtered to separate the silver nanowire and other particles, and the silver nanowire and other particles are separated using a filter paper The amount of silver remaining in the filter paper and the amount of silver that has permeated through the filter paper can be measured to obtain the ratio of the conductive fibers. It is confirmed that the conductive fibers remaining on the filter paper are observed with a TEM and the short axis length of 300 conductive fibers is observed and the distribution thereof is examined to find that the minor axis length is 200 nm or less and the major axis length is 1 占 퐉 or more. It is preferable to use a filter paper which passes particles having a length not larger than the shortest length of the major axis of the conductive fiber at least twice as long as the longest axis of the particles other than the conductive fibers of the above size.

The average short axis length and the average long axis length of the conductive fibers can be obtained by observing TEM images or optical microscopic images using, for example, a transmission electron microscope (TEM) or an optical microscope. In the present embodiment, the average short axis length and the average long axis length of the conductive fibers are obtained by observing 300 conductive fibers by a transmission electron microscope (TEM), and from the average value thereof.

<Binder>

As the binder for immobilizing the conductive fibers, an organic polymer polymer and a group (for example, a carboxyl group, a phosphoric acid group, a sulfonic acid group (for example, a carboxyl group, And the like).

Among these, it is particularly preferable that it is soluble in an organic solvent and can be developed by a weakly alkaline aqueous solution, and also has an acid dissociable group and becomes alkali soluble when an acid dissociable group is dissociated by the action of an acid. The acid dissociable group represents a functional group capable of dissociation in the presence of an acid.

For the production of the binder, for example, a known radical polymerization method can be applied. Polymerization conditions such as the temperature and pressure at the time of producing the alkali-soluble resin by the radical polymerization method, the kind and amount of the radical initiator, the kind of the solvent, and the like can be easily set by those skilled in the art and can be determined experimentally .

As the linear organic polymer, a polymer having a carboxylic acid in its side chain (a photosensitive resin having an acidic group) is preferable.

Examples of the polymer having a carboxylic acid in the side chain include, for example, JP 59-44615 A, JP 54-34327 A, JP 58-12577 A, JP 54-25957 A, JP 54-25957 A, Methacrylic acid copolymers, acrylic acid copolymers, itaconic acid copolymers, crotonic acid copolymers, maleic acid copolymers, and partial acrylic acid copolymers as disclosed in JP-A 59-53836 and JP 59-71048, Acidic cellulose derivatives having a carboxylic acid in the side chain, acid anhydride added to the polymer having a hydroxyl group, and the like, and a polymer having a (meth) acryloyl group in its side chain is also preferable .

Among these, a multi-component copolymer comprising benzyl (meth) acrylate / (meth) acrylic acid copolymer and benzyl (meth) acrylate / (meth) acrylic acid / other monomer is particularly preferable.

Further, a multi-component copolymer containing a (meth) acryloyl group in its side chain or a (meth) acrylic acid / glycidyl (meth) acrylate / other monomer is also useful. The polymer may be used in an arbitrary amount and mixed.

In addition to the above, there may be mentioned 2-hydroxypropyl (meth) acrylate / polystyrene macromonomer / benzyl methacrylate / methacrylic acid copolymer described in JP-A No. 7-140654, 2-hydroxy- Acrylate / polymethyl methacrylate macromonomer / benzyl methacrylate / methacrylic acid copolymer, 2-hydroxyethyl methacrylate / polystyrene macromonomer / methyl methacrylate / methacrylic acid copolymer, 2-hydroxy Ethyl methacrylate / polystyrene macromonomer / benzyl methacrylate / methacrylic acid copolymer, and the like.

&Lt; Conductive polymer &

As the conductive polymer, for example, polyethylene dioxythiophene (PEDOT: PSS: poly (3,4-ethylenedioxythiophene): poly (styrenesulfonate)) containing polystyrene sulfonic acid can be used.

(Example)

Hereinafter, specific examples of the present invention will be described as examples. For comparison with the present invention, the comparative examples are also described. The present invention is not limited to the following examples. In the following description, the term "part" or "%" indicates "part by mass" or "% by mass" unless otherwise specified.

<Fabrication of touch panel module>

First, an ITO film having a thickness of 20 nm was formed on a (reinforced) glass substrate by sputtering, and this was etched to form a first electrode pattern extending in the X direction. Subsequently, on the first electrode pattern, an interlayer insulating film containing SiO ₂ with a thickness of 200 nm was formed by sputtering. Next, Ag paste was applied and sintered to the first electrode pattern, and the first electrode pattern and the control circuit were connected to each other through lead wires.

Subsequently, the conductive film was bonded to the first electrode pattern (on the interlayer insulating film) with the adhesive layer interposed therebetween to manufacture a touch panel module. At this time, an acrylic pressure-sensitive adhesive was used as a pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer. Hereinafter, the production of the conductive film will be described.

(Production of a conductive film)

<Fabrication of Shatterproof Film>

(Production of Cellulose Ester Film A-1)

<Cellulose ester resin>

Cellulose ester resin CE-1 shall be as follows.

CE-1: Cellulose triacetate

(Acetyl group degree of substitution: 2.91, weight average molecular weight (Mw): 300,000)

<Fine Particle Dispersion 1>

Silica fine particles (Aerosil R972V manufactured by Nippon Aerosil Co., Ltd.) 11 parts by mass

Ethanol 89 parts by mass

The mixture was stirred with a dissolver for 50 minutes and then dispersed with Manton-Gaulin.

&Lt; Fine Particle Addition Solution 1 >

The fine particle dispersion 1 was slowly added while sufficiently stirring in a dissolution tank containing methylene chloride. Further, the particles were dispersed in the attritor so that the particle diameter of the secondary particles became a predetermined value. This was filtered with FineMet NF manufactured by Nippon Seisen Co., Ltd. to prepare a fine particle addition liquid 1.

99 parts by mass of methylene chloride

Fine particle dispersion 1 5 parts by mass

<Zhodop A>

A main doping A of the following composition was prepared. First, methylene chloride and ethanol were added to the pressure-dissolving tank. Next, cellulose acetate was added to the pressurized dissolution tank containing the solvent while stirring. This was heated and completely dissolved while stirring. This was filtered using Azumirosi No.244 manufactured by Azumi Co., Ltd. to prepare the main doping A.

Methylene chloride 340 parts by mass

64 parts by mass of ethanol

100 parts by mass of CE-1 (cellulose triacetate)

Polyester compound 6 parts by mass

6 parts by weight of ester compound

Fine particle addition liquid 1 1 part by mass

Was added to a sealed container and dissolved while stirring to prepare a dope. Subsequently, the dope was uniformly plied on the stainless steel belt support at a temperature of 33 DEG C and a width of 1500 mm using an endless belt softening apparatus. The temperature of the stainless steel belt was controlled at 30 占 폚.

Then, on the stainless steel belt support, the solvent was evaporated until the amount of residual solvent in the cast (cast) film was 75%, and then peeled off on the stainless steel belt support at a peel tension of 130 N / m.

The peeled cellulose ester film was stretched by 10% in the transverse direction using a tenter while heating at 160 캜. The residual solvent at the start of the stretching was 15%. Subsequently, drying was completed while conveying the drying zone to a plurality of rolls. The drying temperature was 130 占 폚, and the conveying tension was 100 N / m. After drying, the film was slit to a width of 1.5 m, knurled to 10 mm in width and 10 m in height at both ends of the film, and rolled into a roll to obtain a cellulose ester film A-1 having a dry film thickness of 40 μm. The winding length was 5200 m.

In the cellulose ester film A-1, the in-plane retardation (retardation Ro) was 2 nm. The retardation (Ro) was measured using an automatic birefringence meter KOBRA-21ADH (Ojieiso Kiki K.K.). Incidentally, the retardation Ro (nm) in the in-plane direction of the film is obtained by the following expression.

Ro = (nx-ny) xd

Where d is the thickness of the film (nm), nx is the refractive index in the slow axis direction, and ny is the refractive index in the direction perpendicular to the slow axis in the film plane.

(Production of cellulose ester films A-2 to A-5)

Cellulose ester films A-2 to A-5 were prepared in the same manner as in the cellulose ester film A-1 except that the film thickness and the retardation (Ro) were changed as shown in Table 1.

(Production of PC film A-6)

152400 parts of ion-exchanged water and 84320 parts of a 25% sodium hydroxide aqueous solution were put in a reactor equipped with a thermometer, a stirrer and a reflux condenser, and 9,9-bis (4-hydroxy-3-methylphenyl) fluorene having a purity of 99.8% 34848 parts, 2,2-bis (4-hydroxyphenyl) propane 9008 parts (hereinafter sometimes abbreviated as "bisphenol A"), and hydrosulfite 88 And 178400 parts of methylene chloride was added, followed by stirring. Then 18248 parts of phosgene was blown over 15 minutes at 15 to 25 占 폚 over 60 minutes. After completion of the phosgene suction, a solution of 177.8 parts of p-tert-butylphenol in 2640 parts of methylene chloride and 10560 parts of 25% aqueous sodium hydroxide were added. After the emulsification, 32 parts of triethylamine was added and the mixture was stirred at 28 to 33 ° C for 1 hour The reaction was terminated.

After completion of the reaction, the product was diluted with methylene chloride, washed with water, and acidified with hydrochloric acid. The resultant was washed with water. When the conductivity of the aqueous phase became almost the same as the ion exchange water, the methylene chloride phase was concentrated and dehydrated to obtain polycarbonate Was 20%. The polycarbonate (copolymer A) obtained by removing the solvent from this solution had a molar ratio of the constitutional units of biscresol fluorene to bisphenol A of 70:30 (polymer yield: 97%). The polymer had an intrinsic viscosity of 0.674 and a glass transition temperature (Tg) of 226 ° C.

25 parts by mass of the above polycarbonate was dissolved with stirring at 25 캜 with respect to 75 parts by mass of a mixed solvent of methylene chloride and ethanol containing 4 parts by mass of ethanol to obtain a transparent viscous dope. This dope was plied on a 100 m stainless steel belt controlled by the dew point at 12 캜 or lower by blowing dry air and peeling off. The residual solvent concentration at that time was 35%. From the viewpoint that the peeling property is good and the charge is small, no peeling step or peeling stripe can be seen on the surface of the film by visual observation. Thereafter, when the residual solvent concentration was 2%, the film was stretched twice in the width direction, and then dried while keeping the width. Thereafter, the film was dried until the residual solvent concentration became 1% or less to obtain a PC film A-6 having a width of 1.5 m and a dry film thickness of 80 탆. The winding length was 5200 m. Also. As to the retardation of the PC film A-6, the retardation (Ro) was 500 nm as a result of measurement by the same measurement method as described above.

(Production of COP film A-7)

&Lt; Synthesis of Polymer Resin Having Alicyclic Structure >

Under an ethylene atmosphere, toluene and a phenylnorbornene-toluene solution were added to an autoclave having a capacity of 1.6 liters so that the concentration of phenylnorbornene was 20 mol / l and the total liquid amount was 640 ml. Then, 5.88 mmol of methyl aluminoxane (MAEM 20% toluene solution, manufactured by Aldemar Co., Ltd.) based on Al and 1.5 탆 ol of methylene (cyclopentadienyl) (tetramethylcyclopentadienyl) zirconium dichloride were added, And the mixture was reacted at 80 DEG C for 60 minutes while maintaining the pressure at 0.2 MPa.

After the completion of the reaction, ethylene was depressurized while cooling, and the inside of the system was replaced with nitrogen. Thereafter, 3.0 g of silica (manufactured by Fuji Silysia, grade: G-3 particle size: 50 탆) adjusted to an amount of adsorbed water of 10% by mass was added and reacted for 1 hour. The reaction solution was placed in a pressurized filter (Advantech Co., Ltd., type KST-90-UH) equipped with a filter paper (5C, 90 mm) and Celite (Wako Pure Chemical Industries Co., Ltd.) Respectively. The polymerization solution was added dropwise into the acetone in an amount of 5 times that of the polymerization solution and precipitated to obtain a polymer resin COP1 having an alicyclic structure. The weight average molecular weight of COP1 was 142,000, and the glass transition temperature was 140 占 폚.

The polymer resin COP1 having an alicyclic structure synthesized as described above was dried at 70 DEG C for 2 hours using a hot air dryer in which air was circulated to remove water and then a T multi-layer film having a resin melt- Using a melt extrusion molding machine (T die width of 500 mm), a COP film having a film thickness of 100 占 퐉 was extruded and molded under molding conditions of a molten resin temperature of 240 占 폚 and a T die temperature of 240 占 폚.

Subsequently, the peeled COP film was stretched 90% in the width direction by using a tenter while heating at 200 ° C. Subsequently, drying was completed while conveying the drying zone to a plurality of rollers. The drying temperature was 130 占 폚, and the conveying tension was 100 N / m. After drying, the film was slit with a width of 1.5 m, knurled with a width of 10 mm and a height of 10 탆 at both ends of the film, and rolled up to obtain a COP film A-7 having a dry film thickness of 100 탆. The winding length was 5000 m. The retardation of the COP film A-7 was measured by the same measurement method as above, and as a result, the retardation (Ro) was 0 nm.

(Production of PET film A-8)

<Polyester A>

100 parts by mass of dimethyl terephthalate and 0.1 part by mass of calcium acetate hydrate were added to 64 parts by mass of ethylene glycol, and the transesterification reaction was carried out by a conventional method. 39 parts by mass (7% by mole / total dicarboxylic acid component) of an ethylene glycol solution of 5-sodium sulfonyl (? -Hydroxyethyl) isophthalic acid (concentration 35% by mass), polyethylene glycol ) (5 mass% / polyester produced), 0.05 mass part of antimony trioxide and 0.13 mass part of trimethyl phosphate were added. Subsequently, the temperature was gradually raised, the pressure was reduced, and polymerization was carried out at 280 ° C and 40 Pa to obtain polyester A. Then, the intrinsic viscosity of the polyester A was determined according to the following method, and as a result, the intrinsic viscosity was 0.50 dl / g.

The intrinsic viscosity was calculated by the following procedure using a Ube load type viscometer. 0.6, 1.0 (g / dl) by dissolving the sample using a mixed solvent of phenol and 1,1,2,2-tetrachloroethane having a mass ratio of about 55:45 (adjusted to a dropping time of 42.0 ± 0.1 seconds) (Temperature: 20 캜). The intrinsic viscosity [eta] was obtained by obtaining the specific viscosity [eta] sp at each concentration (C) by the Ube load type viscometer and extrapolating the expression [? Sp / C] to the concentration 0 (C? 0). The unit of intrinsic viscosity [?] Is dl / g.

The pellets of the polyester A were vacuum-dried at 150 ° C for 8 hours and then melt-extruded at 285 ° C using an extruder. The pellets were tightly adhered to a cooling drum at 30 ° C while being electrostatically charged and cooled and solidified to obtain an unstretched sheet. This unstretched sheet was stretched 2.0 times in the longitudinal direction at 90 DEG C by using a roller type longitudinal stretching machine. The temperature difference between the front and back surfaces was within 5 ℃.

The obtained monoaxially stretched film was stretched 1.2 times in the transverse direction at 100 DEG C by using a tenter type transverse stretching machine. Subsequently, the substrate was subjected to heat treatment at 70 占 폚 for 2 seconds, heat set at 150 占 폚 for 10 seconds in the first heat fixing zone, heat set at 180 占 폚 for 15 seconds in the second heat fixing zone, Relaxed, and wound up to prepare a PET film A-8 having a width of 1.5 m and a dry film thickness of 100 탆. The winding length was 5000 m. The retardation of the PET film A-8 was measured by the same measurement method as described above, and as a result, the retardation (Ro) was 3000 nm.

The cellulose ester film, the COP film, the PC film, and the PET film prepared above were used as the shrinkage preventing film of the conductive film.

(Production of hard coating film)

The hard coat layer composition was filtered with a polypropylene filter having a pore diameter of 0.4 탆 on the above-prepared cellulose ester film A-5, PC film A-6, and PET film A-8, and was applied using a microgravure coater . After drying at a constant rate drying temperature of 95 ° C and a decreasing rate of drying temperature of 95 ° C, the coated layer was cured using an ultraviolet lamp at an illuminance of 100 mW / cm ² and an irradiation dose of 0.1 J / cm ² , Thereby forming a hard coat layer having a dry film thickness of 3 탆. Then, the formed film was taken up into a roll-shaped hard coating film. The hard coat layer was formed only as a conductive layer when an ITO conductive film described later was formed.

(Formation of conductive layer)

<Silver nanowire>

Silver nanowires were obtained by the method disclosed in Example 1 (synthesis of silver nanowires) of Japanese Patent Publication No. 2009-505358. That is, in the presence of polyvinylpyrrolidone (PVP), silver nanowires were synthesized by reduction of sulfuric acid in ethylene glycol. The method of reducing metal ions by the reducing power of a polyol (polyhydric alcohol) to precipitate nano-sized metal particles is also referred to as a polyol method.

Subsequently, silver nanowire dispersion liquid was obtained by the method disclosed in Example 8 (Nanowire dispersion) of Japanese Patent Publication No. 2009-505358. That is, about 0.08% wt. Of HPMC (hydroxypropyl methylcellulose), about 0.36% wt. Silver nanowire, about 0.005% wt. Zonyl TM FSO-100 and about 99.555% And mixed to obtain a silver nanowire dispersion coating. This silver nanowire dispersion liquid was applied on a cellulose ester film using a bar coater made by Matsusho Chemical Co., Ltd., and dried at 120 DEG C for 2 minutes to provide a silver nanowire coating film.

<Copper nanowire>

Copper nanowires were prepared by the method described in Japanese Patent Application Laid-Open No. 2002-266007. Namely, 0.1 millimole of the multidentate peptide lipid was placed in a sample bottle, and 100 ml of distilled water containing 8.0 mg (0.20 millimole) of sodium hydroxide equivalent to twice the amount of sodium hydroxide was added thereto, and ultrasonic wave irradiation (bus type) &Lt; / RTI &gt; This aqueous solution was kept at room temperature while stirring vigorously on a hot agitator, and 1 ml of 0.1 mol / liter copper (II) acetate was added thereto. Then, the solution gradually became cloudy, and a blue colloidal dispersion was formed.

Subsequently, the dispersion of the blue colloidal state was stirred at room temperature in the air, and 100 ml (0.5 mmol) of 5 mmol / l sodium borohydride aqueous solution was added. Then, the solution turned blackish brown, and a dark gray color was formed after about 6 hours. The planar precipitate was observed with a transmission electron microscope to confirm the formation of a spherical structure having a diameter of several tens to several hundred nanometers and a copper nanowire. From the transmission electron micrograph, it was found that the copper nanowires had an average diameter of 10 to 20 nm and an average length of 1 to 10 μm or more.

<ITO conductive film>

The indium tin oxide target having the composition In ₂ O ₂ / SnO ₂ = 90/10 was used and a vacuum degree of 10 ^-4 Torr was introduced into the hard coat film by sputtering under argon / An ITO conductive thin film was provided.

<Production of polarizing plate>

Next, the production of the polarizing plate of the display panel will be described. The polarizing plate is manufactured by bonding a surface protective film to one surface of a polarizing film as a polarizer and bonding a back surface protective film to the other surface. First, the production of a surface protective film and a back protective film will be described.

(Production of surface protective film)

<Production of Cellulose Ester Film>

Cellulose ester films B-1 to B-5 and B-7 to B-8 were obtained in the same manner as in the cellulose ester film A-1 except that the film thickness and the retardation (Ro) were changed as shown in Table 1. Respectively.

&Lt; Preparation of acrylic film &

Acrylic film B-6 was prepared in the following manner. Further, the acrylic film B-6 did not contain a plasticizer.

(Production of acrylic film)

A production of the following acrylic resin containing a lactone ring unit was carried out. That is, it was synthesized from 7500 g of methyl methacrylate and 2500 g of methyl 2- (hydroxymethyl) acrylate according to Production Example 1 of paragraphs [0222] to [0224] of Japanese Patent Application Laid-Open No. 2008-9378, %, Tg = 134 캜.

(Formation of acrylic film)

The acrylic resin thus prepared was dried with a vacuum drier at 90 DEG C to adjust the water content to 0.03% or less, 0.3 wt% of a stabilizer (Irganox 1010 (manufactured by Ciba Geigy)) was added, Using a twin-screw kneading extruder under a stream of air, a twin-screw kneading extruder was extruded into water and formed into a strand shape, followed by cutting to obtain pellets having a diameter of 3 mm and a length of 5 mm.

These pellets were dried by a vacuum drier at 90 DEG C and the water content was adjusted to 0.03% or less. Thereafter, the mixture was kneaded using a uniaxial kneading extruder at 210 DEG C for feeding part, 230 DEG C for compression part and 230 DEG C for metering part, And extruded. At this time, a 300 mesh screen filter, a gear pump, and a leaf disk filter with a filtration precision of 7 mu m were arranged in this order between the extruder and the die, and these were connected by a melt pipe. Further, a static mixer was provided in the melt pipe immediately before the die.

Thereafter, melts (molten resin) were extruded on three cast rolls. At this time, the touch roll was brought into contact with the cast roll (cooling roll) on the most upstream side. The touch roll described in Example 1 of Japanese Patent Application Laid-Open No. 11-235747 (described as double restraint roll, the thickness of the thin metal outer tube being 2 mm) was used. The temperatures of the three cast rolls including the cooling rolls were, from the upstream side, the touch roll temperature + 3 占 폚, the touch roll temperature of -2 占 폚, and the touch roll temperature of -7 占 폚.

Thereafter, both ends (5 cm of the entire width) were trimmed immediately before winding, and then subjected to thickness processing (knurling) with a width of 10 mm and a height of 20 탆 at both ends. The film-forming width was 1.5 m and the film-forming speed was 30 m / min. The thickness of the unstretched film after the film formation was 40 탆.

(Preparation of back side protective film)

&Lt; Preparation of acrylic film &

Acrylic films C-1, C-4, and C-8 were prepared in the same manner as in the acrylic film B-6 except that the film thickness was changed as shown in Table 1.

&Lt; Production of COP film &

COP films C-2, C-3, C-6, and C-7 were prepared in the same manner as in COP film A-7 except that the film thickness was changed as shown in Table 1.

<Production of Cellulose Ester Film>

A cellulose ester film C-5 was prepared in the same manner as in the cellulose ester film A-1 except that the film thickness and the retardation (Ro) were changed as shown in Table 1.

(Production of Polarizer)

100 parts by mass of polyvinyl alcohol (hereinafter abbreviated as PVA) having a degree of saponification of 99.95% by mole and a degree of polymerization of 2400 was impregnated with 10 parts by mass of glycerin and 170 parts by mass of water, melt kneaded and defoamed, Melt extrusion and film formation. Thereafter, the PVA film was obtained by drying and heat treatment.

The obtained PVA film had an average thickness of 25 占 퐉, a moisture content of 4.4%, and a film width of 3 m. Then, the obtained PVA film was treated successively in the order of preliminary swelling, dyeing, uniaxial stretching by a wet method, fixing treatment, drying and heat treatment to prepare a polarizing film as a polarizer. That is, the PVA film was preliminarily swollen by immersing in water at 30 ° C for 30 seconds and immersed in an aqueous solution having an iodine concentration of 0.4 g / liter and a potassium iodide concentration of 40 g / liter at 35 ° C for 3 minutes. Subsequently, uniaxial stretching was carried out six times in the aqueous solution at a boric acid concentration of 4% at a temperature of 50 DEG C under a tension applied to the film of 700 N / m, and the concentration of potassium iodide was 40 g / liter, the boric acid concentration was 40 g / And immersed in an aqueous solution of 10 g / liter at a temperature of 30 캜 for 5 minutes to carry out fixation treatment. Thereafter, the PVA film was taken out, subjected to hot air drying at a temperature of 40 占 폚, and then heat-treated at a temperature of 100 占 폚 for 5 minutes. The obtained polarizing film had an average thickness of 13 탆, a transmittance of 43.0%, a polarization degree of 99.5% and a dichroic ratio of 40.1 for the polarization performance

(UV adhesion of the film to the polarizer)

On both sides of a polyvinyl alcohol film (PVA film) having a thickness of 25 占 퐉 in which iodine was adsorbed and oriented, an epoxy resin composition as an ultraviolet curable adhesive was interposed between the surface protective film and the back protective film.

Then, the polarizer was irradiated with ultraviolet rays from the EHAN1700NAL high-pressure mercury lamp 2, which is an ultraviolet lamp provided in an ultraviolet irradiator (manufactured by GS-YUASA), to cure the above adhesive. At this time, the polarizing plate was passed through the surface protective film side of the polarizing plate at a line speed of 11 m / min under the tension of 600 N in the longitudinal direction within the irradiated ultraviolet while closely adhering to the outer circumferential surface of the cooling roll at 23 캜. The ultraviolet accumulated light quantity at that time was 110 mJ / cm ² . The accumulated amount of ultraviolet light was measured based on irradiation in the UVB region of 280 to 320 nm in the wavelength region.

<Assembly of display device with touch panel>

The electrode layer side of the touch panel and the polarizing plate side of the liquid crystal display device were bonded to each other with an adhesive layer interposed therebetween to constitute a liquid crystal display device with a touch panel.

More specifically, SVR1240 manufactured by Sony Chemical & Information Device Co., Ltd. was applied as a pressure-sensitive adhesive on the surface of the protective film of the polarizing plate of the liquid crystal display device, and the liquid crystal display device and the touch panel were bonded to each other through the applied pressure-sensitive adhesive. Then, a part of the pressure-sensitive adhesive was irradiated with ultraviolet rays to temporarily fix the both. Thereafter, it was inspected whether or not air bubbles were generated at the interface, and then the entirety of the pressure-sensitive adhesive was irradiated with ultraviolet rays to be completely cured.

The combinations of the conductive film, the surface protective film and the back surface protective film in the liquid crystal display device with the touch panel according to Examples 1 to 4 and Comparative Examples 1 to 6 are as shown in Table 1.

&Lt; Evaluation of display device with touch panel >

(1) Evaluation of Display Unevenness

The display device with the manufactured touch panel was continuously displayed in black at 120 deg. C under an environment of 60 deg. C and 90%, and the display state at that time was observed. The evaluation criteria at this time are as follows.

○: No glare or whitish spots occur

△: White spot-like stain occurred

X: Surface glare occurred

(2) Evaluation of PVA orientation

The produced display device with a touch panel was subjected to contrast evaluation using a viewing angle characteristic measuring device EZContrast (manufactured by ELDIM). The evaluation criteria at this time are as follows.

○: Contrast is 100%

?: The contrast decrease amount is less than 5%

X: Contrast reduction amount is 5% or more

(3) Polarizer deterioration

The display device with the manufactured touch panel was allowed to stand at 60 DEG C under an environment of 90% for 500 hours, and then the state of black display was observed. The evaluation criteria at this time are as follows.

○: Display is black (not reddish)

△: a little reddish

X: The display is reddish

[Evaluation results]

The evaluation results of Examples 1 to 4 and Comparative Examples 1 to 6 are shown in Table 2.

Comparative Example 1, in which the backside protective film of the polarizing plate contained cellulose ester, exhibited display unevenness of white spot at the time of black display, compared with Examples 1 to 4 and Comparative Examples 2 to 4 containing COP and PMMA 6, display unevenness did not occur. This, COP or PMMA, water vapor transmission rate 200g / m, and ² / 24h or less, the cellulose ester because (water vapor transmission rate 800g / m ² / 24h or more) can inhibit the transmission of moisture as compared to, if the retardation of the protective film (retardation (Ro ) Can be prevented from fluctuating due to the above-mentioned moisture, and it is considered that white spots do not occur even when the black display is performed.

In Comparative Example 6 in which the plasticizer was not included in the surface protective film and the plasticizer was included in the surface protective film, in Comparative Example 6 in which the plasticizer was largely localized on the polarizer side (small on the touch panel side) The contrast was lowered due to the alignment disorder of the polarizer. On the other hand, in Examples 1 to 4 and Comparative Examples 1 and 3 to 5, in which the plasticizer contained in the surface protective film was slightly localized on the polarizer side, the contrast was not lowered due to the orientation disorder of the polarizer. This is because the curing shrinkage of the adhesive at the time of UV bonding of the surface protective film to the polarizer is suppressed by the side (the surface on the harder side) on which the plasticizer is less in the surface protective film (cellulose ester film) This is probably because the orientation confusion is suppressed.

In Comparative Examples 2 to 5 in which at least one of the scattering prevention film of the conductive film and the surface protective film of the polarizing plate was an optical film (PC, PMMA, COP, PET) having high moisture permeability, deterioration of the polarizer occurred, In Examples 1 to 4 and Comparative Examples 1 and 6 in which both the film and the surface protective film contain a cellulose ester film having high hygroscopicity and moisture permeability, the deterioration of the polarizer is small. This is considered to be because the moisture of the conductive layer and the polarizer (PVA) formed by water-based coating is trapped by both of the cellulose ester films, thereby preventing the polarizer from being deteriorated by the moisture. Particularly, since the cellulose ester film of the surface protective film is thin and has a thickness of 15 to 30 탆, water is likely to escape from the polarizer through the surface protective film to the shrinkage preventing film, and deterioration due to moisture of the polarizer is reliably suppressed .

As described above, according to the constitutions of Examples 1 to 4, it is possible to suppress the display irregularity due to the retardation of the back side protective film, the disruption of the PVA orientation due to the curing shrinkage upon UV irradiation (the contrast decrease), and the deterioration of the polarizer due to moisture Can be suppressed.

In addition, apart from the above embodiment, a touch panel A in which a single electrode layer is formed on a glass substrate and a touch panel B in which an electrode layer is formed on the glass substrate in two layers (electrode patterns in X and Y directions) As a result, it was found that the yield of the touch panel A was good (the generation rate of defective products due to disconnection of the electrode layer was small) as much as the number of layers of the electrode layer was small, The productivity was high.

Although the liquid crystal display panel (LCD) is used as the display panel in the embodiment, it is considered that similar results are obtained even when an OLED is used. That is, the display panel may be an LCD or an OLED. Further, in the case of using the OLED, the back surface protective film positioned on the OLED side with respect to the polarizer may be constituted by a 1/4 wavelength plate. The TFT substrate of the OLED may be formed of a resin substrate such as a film.

INDUSTRIAL APPLICABILITY The present invention can be applied to a display device having a touch panel in which a touch panel having an electrode layer on a glass substrate and a display device having a polarizing plate on the display panel are bonded with a pressure sensitive adhesive layer interposed therebetween.

1: Display panel
2: polarizer
3: Polarizer
4: Film
4a: Film substrate (surface protective film, cellulose ester film)
4b: hard coat layer
5: Film (backing protective film)
10: Display device
20: Touch panel
21: glass substrate
22: electrode pattern (electrode layer)
24: conductive film
25: Shatterproof film
26: conductive layer
30: pressure-sensitive adhesive layer

Claims (5)

A display device having a touch panel attached to the electrode layer side of a touch panel having an electrode layer on a glass substrate and a polarizing plate side of a display device having a polarizing plate on the display panel via an adhesive layer,
Wherein the electrode layer of the touch panel is composed of one layer, a conductive film is bonded on the electrode layer,
Wherein the conductive film comprises a film of a scattering prevention film for preventing scattering of the glass substrate, the film including a cellulose ester film, and a conductive layer formed on the opposite side of the electrode layer from the scattering- Lt; / RTI &gt;
The polarizing plate includes a polarizer, a surface protective film adhered to the touch panel side of the polarizer through an ultraviolet curable adhesive, and a back surface protective film adhered to the display panel side of the polarizer through an ultraviolet curable adhesive However,
And the back protective film, the moisture permeability 200g / m of the optical film ² / 24h or less,
The surface protective film is a cellulose ester film having a thickness of 15 to 30 mu m having a plasticizer and is characterized in that the plasticizer is bonded to the polarizer through a surface opposite to the side where the film is largely deviated in the thickness direction And a display panel having a touch panel. The method according to claim 1,
Wherein the polarizing plate has a hard coating layer on the side opposite to the polarizer with respect to the surface protective film. 3. The method according to claim 1 or 2,
Wherein the conductive material is a conductive fiber. The method of claim 3,
Wherein the conductive fiber is a metal nanowire. 5. The method according to any one of claims 1 to 4,
Wherein the optical film of the back side protective film is a film comprising any one of acrylic, cyclic polyolefin, and polycarbonate.

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