JP2018058234A - Hard coat film for bonding of inorganic compound layer, and transparent conductive film and touch panel prepared with the hard coat film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hard coat film that has a hard coat layer having improved adhesion to an inorganic compound layer; particularly, the hard coat film shows little change with time and maintains the adhesiveness satisfactorily.SOLUTION: A hard coat film 1 has a hard coat layer 20. The hard coat layer 20 has particles 21 modified so as to have reactivity and a binder resin 22. The content of the particles is 1-60 pts.wt. relative to 100 pts.wt. of the binder resin solid content, and the particles are 1-100 nm in particle diameters. The hard coat layer is provided on a support 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hard coat film having a hard coat layer for bonding an inorganic compound layer, which is suitable for an electrode film, a gas barrier film and the like.

An electrode film used for a touch panel is formed by forming an ITO (tin-doped indium oxide) film by sputtering on a hard coat layer laminated on the surface of a transparent substrate, and forming an electrode pattern by etching on the ITO film. .
Patent Document 1 discloses a technique of a hard coat film in which, when a transparent conductive layer such as ITO is formed on the hard coat layer, these layers have good adhesiveness.
However, in the electrode film in which ITO is formed on the hard coat layer, a difference in optical characteristics (transmittance, hue, reflectance, etc.) occurs between the portion where the ITO film is present and the portion where the ITO is removed. The phenomenon that you can see occurs, and it looks bad. Therefore, in recent years, electrode films have come to have a configuration in which an optical adjustment layer for adjusting optical characteristics is disposed between a hard coat layer and an ITO film. Thereby, the difference between the optical characteristics in the portion where the ITO film is present and the optical characteristics in the portion where the ITO film is removed and the optical adjustment layer is exposed becomes small, and the electrode pattern becomes inconspicuous.

Japanese Patent Laying-Open No. 2015-183168

  As described above, in the electrode film having the optical adjustment layer between the hard coat layer and the ITO film, since the optical adjustment layer is formed on the hard coat layer by the sputtering method, the adhesion to the optical adjustment layer is good. A film having a hard coat layer is required. In particular, in order to increase the reliability of the electrode film, it is desired that the change with time is small and the adhesiveness with the optical adjustment layer is maintained well.

  Patent Document 1 discloses a good adhesion between the hard coat layer and ITO by blending a predetermined hydrophobic silica gel and a specific leveling agent into the hard coat layer, but the adhesion with the optical adjustment layer is disclosed. Is not disclosed or suggested.

  Accordingly, an object of the present invention is to provide a hard coat film (hereinafter referred to as “hard coat film”) having a hard coat layer with improved adhesion to an inorganic compound layer. In particular, an object is to provide a hard coat film that is less changed with time and maintains good adhesion.

  In the hard coat film of the present invention, the inorganic compound layer is bonded onto the hard coat layer. The hard coat layer includes particles modified to have reactivity and a binder resin, and the content of the particles is 1 part by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the binder resin solid content.

  In the hard coat film of the present invention, the average particle diameter of the particles is preferably 100 nm or more and 1000 nm or less.

  In the hard coat film of the present invention, preferably, when the particles constitute secondary particles as an aggregate of primary particles, the diameter of the primary particles is 1 nm or more and 100 nm or less.

  In the hard coat film of the present invention, preferably, the particles are silica, alumina, titanium, zirconia, calcium carbonate, magnesium carbonate, barium sulfate, or a combination of two or more thereof.

  In the hard coat film of the present invention, preferably, the particles have an acryloyl group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, an isocyanate group, or a combination of two or more of these functional groups.

  Moreover, the value of the bending resistance test of the hard coat layer measured by the cylindrical mandrel method according to JIS-K5600-5-1 (1999) is preferably 6 mm or less for the hard coat film of the present invention.

  In addition, the hard coat film of the present invention preferably has an inorganic compound layer peeled only partially from the hard coat layer in an hourglass cross-cut peel test after laminating an inorganic compound layer on the film and boiling it. No or better.

  In the hard coat film of the present invention, preferably, the inorganic compound layer is an optical adjustment layer or a gas barrier layer.

In the hard coat film of the present invention, preferably, the inorganic compound is SiO ₂ or Nb ₂ Ox (where 4 ≦ x ≦ 5).

  In the hard coat film of the present invention, the inorganic compound layer is preferably composed of a single layer or multiple layers.

  The transparent conductive film of the present invention is characterized by using the above-described hard coat film of the present invention.

  The touch panel of the present invention is characterized by using the above-described hard coat film of the present invention.

  According to the present invention, the adhesion between the inorganic compound layer and the hard coat layer can be improved. In particular, there is little change over time, and good adhesion is maintained.

(A) Sectional drawing which shows an example of embodiment of the hard coat film of this invention, (b) Sectional drawing which shows the other example of embodiment of the hard coat film of this invention, (c) Hard coat film of this invention Sectional drawing which shows the other example of embodiment Sectional drawing which shows an example of the hard coat film by which the inorganic compound layer was laminated | stacked Top view explaining the shape of the cut in the hourglass crosscut peel test (a) Sectional drawing which shows an example of the transparent conductive film to which the hard coat film of this invention was applied, (b) Sectional structure and transparent conductivity of the transparent conductive film of (a) where the transparent conductive film was etched The figure explaining the light which the film reflected (a) A cross-sectional view of a hard coat film of the present invention in which an SiO ₂ film is laminated on a hard coat layer, (b) an Nb ₂ Ox (where 4 ≦ x ≦ 5) film and an SiO ₂ film are hard coated in this order Sectional view of the hard coat film of the present invention laminated on the layer

  Hereinafter, an embodiment of the hard coat film 1 for bonding the inorganic compound layer 40 of the present invention will be described with reference to FIGS. The inorganic compound layer 40 may be a layer containing an inorganic compound or a layer containing the inorganic compound itself as long as it is a layer having an inorganic compound.

  The hard coat film 1 of the present invention has a hard coat layer 20, includes particles (reactive modified particles) 21 modified so that the hard coat layer 20 has reactivity, and a binder resin 22. The content of the particles 21 is 1 to 60 parts by weight with respect to 100 parts by weight of the binder resin 22.

  As shown in FIG. 1A, the embodiment of the present invention includes a support 10 and a hard coat layer 20 formed on the support 10 as a basic configuration. The hard coat film 1 is not limited to that shown in FIG. 1A, and may be a single hard coat layer film (FIG. 1B), or the hard coat layer 20 of the support 10 is formed. A back coat layer (FIG. 1C) may be provided on the surface opposite to the formed surface.

  In such a hard coat film 1, as shown in FIG. 2, the inorganic compound layer 40 is laminated on the hard coat layer 20. At this time, the hard coat layer 20 has excellent adhesion to the inorganic compound layer 40.

  First, the reactive modified particles 21 and the binder resin 22 constituting the hard coat layer 20 will be described.

  The binder resin 22 has a function as a binder of the reactive modified particles 21 described later. The binder resin 22 desirably has a reactive functional group. In that case, it can bind to the reactive functional group of the reactive modified particle 21 and effectively prevent the reactive modified particle 21 from falling off. Examples of the reactive functional group of the binder resin 22 include an acryloyl group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, and an isocyanate group.

  As the binder resin 22, resins such as an ionizing radiation curable resin, a thermosetting resin, and a thermoplastic resin can be used alone or in combination of two or more, and they can be used properly according to the purpose. Among these, it is preferable to use an ionizing radiation curable resin when higher hardness is required.

  Examples of the ionizing radiation curable resin include resins that can be crosslinked and cured by irradiation with ionizing radiation (ultraviolet rays or electron beams). For example, one or two (meth) acryloyl groups are contained in one molecule. The acrylic resin that has is particularly preferably used. Examples of the acrylic compound include urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, polyfluoroalkyl (meth) acrylate, and silicone (meth) acrylate. .

  Examples of the thermosetting resin include polyester acrylate resins, polyurethane acrylate resins, epoxy acrylate resins, epoxy resins, melamine resins, phenol resins, and silicone resins.

  Examples of thermoplastic resins include polyester resins, acrylic resins, polycarbonate resins, cellulose resins, acetal resins, vinyl resins, polyethylene resins, polystyrene resins, polypropylene resins, polyamide resins, and polyimide resins. Examples thereof include resins and fluorine resins.

Moreover, it is more preferable that the binder resin 22 includes a certain amount of a high molecular weight resin. By combining the high molecular weight resin and the reactive modified particles 21 described later, a certain degree of flexibility can be imparted to the hard coat layer 20 without impairing the hardness, and the inorganic compound layer 40 with respect to the hard coat layer 20 can be imparted. Anchor effect increases. Thereby, the adhesiveness of the hard-coat layer 20 and the inorganic compound layer 40 improves more.
The high molecular weight resin is a resin having a weight average molecular weight (Mw) of 10,000 or more, preferably 10,000 to 150,000, more preferably 30,000 to 100,000.
As the high molecular weight resin, an ionizing radiation curable resin, a thermosetting resin, a thermoplastic resin, or the like can be used alone or in combination of two or more. Examples of the ionizing radiation curable resin, thermosetting resin, and thermoplastic resin are the same as those listed above as examples of the ionizing radiation curable resin, thermosetting resin, and thermoplastic resin of the binder resin 22.
As content, it is 1 to 50 weight part with respect to 100 weight part of binder resin 22 (solid content), More preferably, it is 5 to 40 weight part. When the binder resin 22 includes a high molecular weight resin, the “binder resin 22 (solid content)” refers to the solid content of the entire binder resin 22 including the high molecular weight resin.

The reactive modified particles 21 contribute to improving the adhesion of the hard coat layer 20 to the inorganic compound layer 40 and maintaining the adhesion over time.
The reactive modified particle 21 is a particle in which a reactive functional group is added to the surface of the inorganic particle by modifying the surface of the inorganic particle. The reactive functional group is bonded to the reactive functional group of the binder resin 22, thereby preventing the reactive modified particles 21 from falling off the hard coat layer 20. Moreover, it is guessed that adhesiveness with an inorganic compound layer can be maintained even in a high temperature and high humidity state by having a reactive functional group.
Examples of inorganic particles include silica, alumina, titanium, zirconia, calcium carbonate, magnesium carbonate, barium sulfate, and the like, and these inorganic particles can be used alone or in combination of two or more. Examples of the reactive functional group include an acryloyl group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, and an isocyanate group, and these can be used alone or in combination of two or more of these reactive functional groups. I can do it.

The content of the reactive modified particle 21 is 1 part by weight with respect to 100 parts by weight of the binder resin 22 (solid content) so that the lower limit of the reactive modified particle 21 is 100 parts by weight of the binder resin 22 (solid content). Above, preferably 3 parts by weight or more, more preferably 5 parts by weight or more, and most preferably 10 parts by weight or more. On the other hand, the upper limit value of the reactive modified particles 21 is not particularly determined, but is 60 parts by weight or less, preferably 40 parts by weight or less, more preferably 30 parts by weight or less with respect to 100 parts by weight of the binder resin 22 (solid content). It is.
When the content of the reactive modified particles 21 is less than the above range, the adhesion with the inorganic compound layer 40 tends to be weak. On the other hand, when the amount is larger than the above range, it is difficult to maintain transparency, which is not preferable.

The reactive modified particles 21 may be primary particles or secondary particles that are aggregates as long as they have a predetermined size. However, in order to obtain more adhesiveness, secondary particles are preferable. When secondary particles, which are aggregates of primary particles, are used as the reactive modified particles 21, the reason why the adhesion is improved compared with the case where primary particles having the same size are simply used is not clear. This is probably because the contact area between the particles protruding from the surface and the inorganic compound layer 40 increases.
The average particle diameter of the reactive modified particles 21 (including secondary particles as primary particles or aggregates composed of primary particles) varies depending on the thickness of the hard coat layer 20 and therefore cannot be generally stated, but the lower limit is 100 nm. As mentioned above, Preferably it is 110 nm or more, More preferably, it is 130 nm or more. Moreover, an upper limit is 1000 nm or less, Preferably, it is 800 nm or less, More preferably, it is 600 nm or less. Furthermore, among the above, when the reactive modified particles 21 are composed of secondary particles as aggregates of primary particles, the average particle diameter of the primary particles that are constituents of the secondary particles has a lower limit of 1 nm or more, Preferably, it is 20 nm or more, more preferably 30 nm or more. The upper limit value is 100 nm or less, preferably 80 nm or less, and more preferably 60 nm or less.
In the case where the average particle diameter of the reactive modified particles 21 or the reactive modified particles 21 are composed of secondary particles, the adhesiveness to the inorganic compound layer 40 is improved by setting the average particle diameter of the primary particles to the above-described lower limit value or more. Can be obtained. On the other hand, by setting these average particle diameters to be equal to or less than the above-described upper limit values, light transmittance that can be used for transparent applications can be obtained.
In addition, the average particle diameter of particle | grains points out the value of the volume average particle diameter (D50) which can be measured with a laser diffraction / scattering method.

The hard coat layer 20 may further contain a photoinitiator, a curing agent, or the like depending on the curing method.
Photoinitiators include photo radical polymerization initiators such as acetophenones, benzophenones, Michler ketone, benzoin, benzylmethyl ketal, benzoylbenzoate, α-acyl oxime esters, thioxanthones, onium salts, sulfonate esters, organometallic complexes And a cationic photopolymerization initiator.
Moreover, as a hardening | curing agent, compounds, such as polyisocyanate, an amino resin, an epoxy resin, and carboxylic acid, can be suitably used according to suitable resin.

  In the hard coat layer 20, in addition to the binder resin, polymer resin, reactive modified particles, photoinitiator, and curing agent described above, an antistatic agent, a dispersant, a flocculant, Additives such as ultraviolet absorbers, antioxidants, and leveling agents may be further included.

When the hard coat film 1 includes the support 10, the thickness of the hard coat layer 20 (see L in FIG. 1A) is 0.1 to 10.0 μm, preferably 0.5 to 5.0 μm. Preferably it is 1.0-3.0 micrometers. Further, when the hard coat film 1 is provided with the back coat layer 30 in addition to the support 10, it is 0.1 to 10.0 μm, preferably 1.0 to 5.0 μm, more preferably 1.0 to 3.0 μm. It is. By having such a thickness, the adhesion between the hard coat layer 20 and the inorganic compound layer 40 is improved.
In the case of a single hard coat layer, the thickness is 0.1 to 10.0 μm, preferably 0.5 to 5.0 μm, more preferably 1.0 to 3.0 μm. By setting the thickness to 0.1 μm or more, the coating film strength is sufficient while the adhesiveness with the inorganic compound layer 40 is maintained, and the handling property is favorable.
The thickness of the hard coat layer 20 is measured using a reflection spectral film thickness meter (Otsuka Electronics FE-300).

Next, the support 10 when the hard coat film 1 has the support 10 will be described. The support 10 can be used without any particular limitation as long as it is a plastic film having high optical transparency. For example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polycycloolefin, polyethylene, polycarbonate, polypropylene, polystyrene, triacetyl cellulose, acrylic, polyvinyl chloride, norbornene compound and the like can be used. Of these, a stretched polyethylene terephthalate film, particularly a biaxially stretched film, is preferred because of its excellent mechanical strength and dimensional stability. Moreover, in order to improve adhesiveness with the hard-coat layer 20, what gave the surface a corona discharge process or provided the easily bonding layer is used suitably. In addition, it is preferable that the thickness of the support body 10 is normally about 6-250 micrometers, More preferably, it is about 23-188 micrometers.
The support 10 is preferably light transmissive, and specifically has a total light transmittance (JISK7136) of 85% or more, preferably 90% or more.

Further, as described above, the hard coat film 1 may further include a back coat layer 30 (FIG. 1C) on the surface opposite to the hard coat layer 20 of the support 10.
In this case, the back coat layer 30 is not particularly limited, but can be selected from a hard coat layer, an adhesive layer, an antistatic layer, and the like, and the hard coat layer 20 described above may be provided.

  The method for producing the hard coat film 1 is not particularly limited. For example, when the support 10 is provided, a hard coat layer coating solution obtained by dissolving or dispersing the above-described hard coat layer 20 material in an appropriate solvent is used for bar coating. It can be prepared by coating on a support by a known method such as, drying, and irradiating with ultraviolet rays as necessary. Further, by forming a release layer on the support 10 in advance, after forming the hard coat layer 20 on the support 10, the support 10 is peeled and removed, so that the hard coat layer can be separated from the single layer. It can be set as the film which becomes. Further, in the case of the hard coat film 1 having the back coat layer 30, the back coat dissolved or dispersed in a suitable solvent on the surface opposite to the hard coat layer 20 of the support 10 provided with the hard coat layer 20. The layer coating solution can be applied by a known method such as bar coating, dried, and irradiated with ultraviolet rays as necessary.

  Next, the characteristics of the hard coat layer 20 will be described. The properties that the hard coat layer 20 should have are adhesion and flexibility.

  First, the adhesiveness is, for example, a state in which an inorganic compound layer is laminated and nothing is treated (hereinafter referred to as “initial adhesiveness test”) and a state after performing boiling treatment which is an accelerated weathering test (hereinafter referred to as “initial adhesion test”). The hourglass cross-cut peel test is performed in two types of states (hereinafter referred to as “adhesion test after boiling”), and the superiority or inferiority can be determined and evaluated according to the result. As will be described later, the hourglass cross-cut peel test is performed by cross-cutting the surface of the inorganic compound layer 40 into an hourglass-like shape, so that it adheres under conditions more severe than cross-cutting. Can be evaluated.

  Here, the initial adhesiveness test method (hourglass crosscut peel test method) is as follows.

A test piece in which an inorganic compound layer 40 having a thickness of about 200 nm is formed by sputtering an inorganic compound (for example, SiO ₂ , Nb ₂ Ox (where 4 ≦ x ≦ 5), etc.) on the hard coat film 1 (test) Piece production process).

  Next, as shown in FIG. 3, the surface of the inorganic compound layer 40 is cut so that the line segment DD ′ and the line segment EE ′ are parallel and the width between these line segments is 2 cm. Next, the line segment FF ′ and the line segment GG ′ intersect with each other, one end portions of the line segments FF ′ and GG ′ intersect with the line segment DD ′, and the other end portions of the line segments FF ′ and GG ′ respectively A cut is made in the surface of the inorganic compound layer 40 so as to intersect with the minute EE ′. At this time, the two triangles ABC and AB′C ′ formed by the line segments DD ′, EE ′, FF ′ and GG ′ are cut so as to form an isosceles triangle having an apex angle of 30 degrees and a height of 1 cm. . Here, a point where the line segment FF ′ and the line segment GG ′ intersect is a vertex A, an intersection point of the line segment GG ′ and the line segment FF ′ on the line segment DD ′ is a point B and a point C, respectively, and the line segment EE The intersecting points of the line segment GG ′ and the line segment FF ′ on “′ are point B ′ and point C ′, respectively (cutting step).

  Adhesive tape (manufactured by Nichiban Co., Cellotape (registered trademark)) is adhered so as to cover the two isosceles triangles with cuts, and the adhered adhesive tape is pulled away at a predetermined angle and speed (first peeling) . Next, a peel test is performed again in the same place where the first peel is performed on the test piece after the first peel using a newly prepared adhesive tape (second peel). In addition, it carries out based on the cross-cut method prescribed | regulated to JISK5600-5-6 except performing the cutting method mentioned above and peeling twice in the same place continuously (peeling process).

  Tested according to the initial adhesion test method, in the present invention, the adhesion of the hard coat layer is preferably such that the inorganic compound layer 40 is not peeled off from the hard coat layer 20 at the second peeling. By having such adhesiveness, the adhesiveness over time to the inorganic compound layer 40 is improved.

In addition, the post-boiling adhesion test method is a method in which the test piece obtained in the test piece preparation step is subjected to pure water at a predetermined time after the test piece preparation step in the initial adhesion test method described above and before the cutting step. The point which has the process (boiling process process) of using and boiling is different from the initial adhesiveness test method.
Incidentally, the boiling process, the inorganic compound layer 40 in the case of SiO ₂ is boiled for 6 hours. When the inorganic compound layer 40 is Nb ₂ Ox (where 4 ≦ x ≦ 5), boiling is performed for 1 hour.

In the present invention, the adhesion of the hard coat layer is determined according to the post-boil adhesion test method, and the inorganic compound layer 40 is only partially peeled from the hard coat layer 20 in the first or second peeling. Or better than that, and in the first or second peeling, the inorganic compound layer 40 is more preferable than the one in which the inorganic coating layer 40 is only partially peeled off, and in the second peeling, More preferably, the inorganic compound layer 40 is not peeled off from the hard coat layer 20 at all.
By having such adhesiveness, the adhesiveness to the inorganic compound layer 40 under high temperature and high humidity is improved.

Alternatively, when the initial adhesion test and the post-boil adhesion test method are combined, in the present invention, the adhesion of the hard coat layer 20 is that the inorganic compound layer 40 is hard coated by the second peeling of the initial adhesion test. What is not peeled off from the layer 20 at all and is better than that in which the inorganic compound layer 40 is only partially peeled off from the hard coat layer 20 in the first peeling after the boiling test is preferable. The inorganic compound layer 40 is not peeled off from the hard coat layer 20 at the second peeling, and the inorganic compound layer 40 is peeled only partially from the hard coat layer 20 at the second peeling in the adhesion test after boiling. Those that are better than those that are not are more preferred.
By having such adhesiveness, even with severe environments such as high temperature and high humidity, changes with time are unlikely to occur, and the initial adhesiveness can be maintained.

Further, the flexibility of the hard coat layer 20 can be evaluated by a bending resistance test. Since the value of the bending resistance test varies depending on the material and thickness of the hard coat layer 20, or when the hard coat film 1 has the support 10 and the back coat layer 30, depending on the type and thickness thereof, As a support, a film thickness of 125 μm made of Teijin DuPont's easy-adhesive PET film “KFL10W” was used, and a flex resistance test was performed under the condition that no layer other than the easy-adhesion layer was laminated on the back surface.
In the present invention, the value of the bending resistance test (the diameter of the iron bar in which the hard coat layer is cracked or peeled off from the support for the first time) is preferably 6 mm or less, more preferably 2 mm or less. By setting the value of the bending resistance test to a predetermined value or less, the hard coat layer 20 has flexibility and the adhesion to the inorganic compound layer 40 can be improved. In addition, the value of a bending test is a value measured by the cylindrical mandrel method based on JIS-K5600-5-1 (1999).

  Next, the optical characteristics that the hard coat film 1 of the present invention should have will be described.

  As an optical characteristic of the hard coat film 1, the total light transmittance (JISK7136) is preferably 85% or more, and more preferably 90% or more. By providing such light transmittance, the adhesiveness to the inorganic compound layer 40 can be imparted without hindering the visibility of a display device or the like to which the hard coat film 1 is attached.

  The haze (JISK7136) of the hard coat film 1 is preferably 4.0% or less, more preferably 2.0% or less, still more preferably 1.0% or less, and most preferably 0.8% or less. A suitable haze can be maintained by adjusting the content according to the average particle diameter of the particles.

Next, an application example of the hard coat film 1 will be described taking the hard coat film 1 having the structure shown in FIG.
FIG. 2 shows an example of a hard coat film (laminated body) 2 on which the inorganic compound layer 40 is laminated. The laminate 2 is formed by adhering the inorganic compound layer 40 on the hard coat layer 20 of the hard coat film 1.

Examples of the inorganic compound layer 40 include an optical adjustment layer 50 or a gas barrier layer 51.
When the optical adjustment layer 50 is laminated | stacked on the hard-coat layer 20, the hard-coat film 1 is used for the film 3 with an optical adjustment layer (FIG. 2). Moreover, as shown in FIG. 4A, the hard coat film 1 of the present embodiment is used for the transparent conductive film 4 by further laminating a transparent conductive film 60 on the optical adjustment layer 50. it can. The film 3 with an optical adjustment layer and the transparent conductive film 4 can be used as an electrode sheet member of a capacitive type or resistive film type touch panel.

The inorganic compound of the optical adjustment layer 50 may be any compound that adjusts the optical characteristics of the transparent conductive film 60, and examples thereof include SiO ₂ and Nb ₂ Ox (where 4 ≦ x ≦ 5). Further, the optical adjustment layer 50 may be composed of a single layer or multiple layers. In the case of a single layer, as shown in FIG. 5A, for example, a SiO ₂ film is formed on the hard coat layer 20 as the optical adjustment layer 50. In the case of a multilayer, as shown in FIG. 5B, for example, an Nb ₂ Ox (where 4 ≦ x ≦ 5) film and an SiO ₂ film are laminated on the hard coat layer 20 in that order. The lamination of SiO ₂ or Nb ₂ Ox (where 4 ≦ x ≦ 5) may be performed by a conventionally known method, and is formed by sputtering or vapor deposition.

Examples of the transparent conductive film 60 include films made of tin-doped indium oxide (ITO), zinc oxide (ZnO), aluminum-doped zinc oxide (AZO), silver, copper or copper alloys, carbon nanotubes, and the like. The transparent conductive film 60 may be laminated by a conventionally known method, and is formed by a sputtering method such as DC sputtering or RF sputtering or a vapor deposition method. When used for a capacitive touch panel, a desired electrode pattern is formed by etching the formed transparent conductive film 60 (FIG. 4B).
When such an electrode pattern is formed, the optical adjustment layer 50 makes the electrode pattern invisible. For example, in the case of the transparent conductive film 4 provided with the ITO electrode pattern, as shown in FIG. 4B, the optical adjustment layer 50 includes light 71 reflected by the ITO removed portion and light reflected by the remaining ITO portion. The difference in optical characteristics (reflectance, hue, transmittance, etc.) from 70 is reduced, making the ITO electrode pattern difficult to see.

  On the other hand, when the gas barrier layer 51 is laminated | stacked on the hard-coat layer 20, the hard-coat film 1 is used for the gas barrier film 5 suitable for EL display, EL illumination, a solar cell, etc. (FIG. 2). Examples of the inorganic compound of the gas barrier layer 51 include magnesium, titanium, aluminum, indium, silicon, tin, and oxides thereof, and these can be used alone or in combination of two or more. Aluminum or aluminum oxide is preferably used in terms of workability and cost. The gas barrier layer 51 may be stacked on the hard coat layer 20 by a conventionally known method, which is formed by sputtering or vapor deposition.

  According to the hard coat film 1 of the present invention, the adhesion of the hard coat layer 20 to the inorganic compound layer 40 can be improved. In particular, there is little change with time, and good adhesion can be maintained.

  Examples of the protective film of the present invention will be described below. In the following examples, “%” and “parts” are based on weight unless otherwise specified.

<Example 1>
A hard coat layer having a thickness of 2.0 μm is formed by applying a hard coat coating solution having the following formulation on one surface of a 125 μm-thick polyethylene terephthalate film (KFL10W, manufactured by Teijin DuPont), drying, and then curing with ultraviolet light Then, the hard coat film of Example 1 was produced.

<Coating liquid for hard coat>
-Binder resin ionizing radiation curable resin 30 parts (Unidic 17-813: DIC, solid content 80%)
15 parts of high molecular weight resin (Acridic A195: DIC, solid content 40%)
(Weight average molecular weight: 85000)
・ Reactive modified particle dispersion 15 parts (SIRMIBK30WT% -M06: CIK Nanotech, solid content 30%)
(Silica particles: average primary particle size 30 nm, average secondary particle size 200-300 nm)
・ Diluted solvent 60 parts ・ Photoinitiator 0.4 parts (Irgacure 184: BASF)

<Example 2>
A protective film of Example 2 was obtained in the same manner as in Example 1 except that the weight part of the reactive modified particles in the coating liquid for hard coat of Example 1 was changed to 30.

<Example 3>
A protective film of Example 3 was obtained in the same manner as in Example 1 except that the weight part of the reactive modified particles in the coating liquid for hard coat of Example 1 was changed to 60.

<Comparative Example 1>
A protective film of Comparative Example 1 was obtained in the same manner as in Example 1 except that the reactive modified particles were removed from the hard coat coating solution of Example 1.

  The following characteristics were evaluated about the protective film manufactured by the Example and comparative example which were mentioned above.

1. Optical properties According to the JISK7136 measurement method, using a haze meter (Suga Test Instruments Co., Model HGM-2K) and a color computer (Suga Test Instruments Co., Model SM-4) The light transmittance (Tt) and haze were measured.

  3. Regarding “flexion resistance”, based on the flex resistance (cylindrical mandrel method) based on JIS-K5600-5-1 (1999), we prepared iron bars with diameters of about 3 mm and 7 mm. The protective film with a hard coat layer is folded and wound so that the hard coat layer 20 is on the outside, and whether or not the hard coat layer 20 in the wound portion is cracked or peeled off from the support is visually observed. As a result, it was confirmed that the crack or peeling from the support was not confirmed with a 3 mm iron bar, and the crack or peeling from the support was confirmed with a 3 mm iron bar, but the crack or support was not observed with a 7 mm iron bar. The case where peeling from the steel was not confirmed was evaluated as “Δ”, and the case where cracking or peeling from the support was confirmed in either iron bar was evaluated as “x”.

4). Initial adhesion test (hourglass crosscut peel test)
On the hard coat layer of the hard coat film produced in the above-described Examples and Comparative Examples, SiO ₂ or Nb ₂ Ox (however, 4 ≦ x ≦ 5) by a sputtering apparatus (manufactured by Shibaura Mechatronics: CFS-4EP-LL). ) Was sputtered to prepare a test piece on which an inorganic compound layer 40 having a thickness of about 200 nm was formed (test piece preparation step).

  Next, as shown in FIG. 3, the surface of the inorganic compound layer 40 was cut so that the line segment DD ′ and the line segment EE ′ were parallel and the width between these line segments was 2 cm. . Next, the line segment FF ′ and the line segment GG ′ intersect with each other, one end portions of the line segments FF ′ and GG ′ intersect with the line segment DD ′, and the other end portions of the line segments FF ′ and GG ′ respectively A cut was made in the surface of the inorganic compound layer 40 so as to intersect with the minute EE ′. At this time, the two triangles ABC and AB′C ′ formed by the line segments DD ′, EE ′, FF ′ and GG ′ are cut so as to form an isosceles triangle having an apex angle of 30 degrees and a height of 1 cm. It was. Here, a point where the line segment FF ′ and the line segment GG ′ intersect is a vertex A, an intersection point of the line segment GG ′ and the line segment FF ′ on the line segment DD ′ is a point B and a point C, respectively, and the line segment EE The intersecting points of the line segment GG ′ and the line segment FF ′ on “′ are point B ′ and point C ′, respectively (cutting step).

  Adhesive tape (manufactured by Nichiban Co., Cellotape (registered trademark)) was adhered so as to cover the two isosceles triangles with cuts, and the adhered adhesive tape was pulled away at a predetermined angle and speed (first peeling) ). Next, a peel test was performed again in the same place where the first peeling was performed on the test piece after the first peeling using the newly prepared adhesive tape (second peeling). In addition, it carried out based on the cross-cut method prescribed | regulated to JISK5600-5-6 except performing the cutting method mentioned above and peeling twice in the same place continuously (peeling process).

  In this peel test, the case where the inorganic compound layer 40 is not peeled off from the hard coat layer 20 is ○ (no peel), and the case where the inorganic compound layer 40 is partially peeled off from the hard coat layer 20 is Δ (partial peel is present) ), The case where the inorganic compound layer 40 was peeled off almost from the hard coat layer 20 was evaluated as x (all peeled).

5. Post-boil adhesion test method When the inorganic compound layer was SiO ₂ , the test piece was boiled in pure water for 6 hours after the test piece preparation step of the initial adhesion test described above (boiling treatment step). Next, the cutting process and the peeling process described above are performed, and the inorganic compound layer 40 is partially peeled off from the hard coat layer 20 when the inorganic compound layer 40 is not peeled off from the hard coat layer 20 (no peeling). The case where the inorganic compound layer 40 was peeled off almost from the hard coat layer 20 was shown as x (all peeled).
When the inorganic compound layer is Nb ₂ Ox (where 4 ≦ x ≦ 5), in the above-described boiling treatment step, tests and evaluations were performed in the same manner as in the case of SiO ₂ except that the boiling time was 1 hour. went.

  Table 1 shows the results.

Regarding the evaluation of adhesiveness, the adhesiveness to SiO ₂ and Nb ₂ Ox (where 4 ≦ x ≦ 5) in the initial adhesive test in the films of Experimental Examples 1 to 3 was “no peeling” in the first and second peeling. "Met. In addition, the adhesion to SiO _{2 in the} post-boil adhesion test of these examples was “no peeling” in the first peeling, “partial peeling” or “no peeling” in the _second peeling, and Nb ₂ Ox (however, 4 ≦ x ≦ 5) All except for Example 1 were “no peeling” in both the first and second peeling.
On the other hand, the evaluation of the adhesion of the film of Comparative Example 1 to SiO ₂ and Nb ₂ Ox (4 ≦ x ≦ 5) is inferior to those of Examples 1 to 3 in the initial adhesion test, and the post-boil adhesion test Then it was “all peeling”.
These results show that the films of Examples 1 to 3 having the reactive modified particles 21 hardly change over time even in a severe environment such as high temperature and high humidity, and can maintain the adhesiveness to the initial inorganic compound layer 40. Indicated.

  Regarding flexibility, Examples 1 to 3 were more flexible than Comparative Example 1. Therefore, it was found that the adhesion to the inorganic compound layer 40 is improved by providing the hard coat layer 20 with appropriate flexibility.

DESCRIPTION OF SYMBOLS 1 ... Hard coat film, 20 ... Hard coat layer, 21 ... Reactive modified particle, 22 ... Binder resin, 40 ... Inorganic compound layer, 50 ... Optical adjustment layer, 51. ..Gas barrier layer

Claims (12)

A hard coat film having a hard coat layer for bonding an inorganic compound layer,
The hard coat layer includes particles modified to have reactivity and a binder resin,
The hard coat film, wherein the content of the particles is 1 part by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the binder resin solid content. The hard coat film according to claim 1,
An average particle diameter of the particles is 100 nm or more and 1000 nm or less. The hard coat film according to claim 1 or 2,
When the particles constitute secondary particles as aggregates of primary particles, the diameter of the primary particles is from 1 nm to 100 nm. The hard coat film according to any one of claims 1 to 3,
The hard coat film, wherein the particles are silica, alumina, titanium, zirconia, calcium carbonate, magnesium carbonate, barium sulfate, or a combination of two or more thereof. The hard coat film according to any one of claims 1 to 4,
The hard coat film, wherein the particles have an acryloyl group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, an isocyanate group, or a combination of two or more of these functional groups. The hard coat film according to any one of claims 1 to 5,
A hard coat film, wherein a value of a bending resistance test of the hard coat layer measured by a cylindrical mandrel method according to JIS-K5600-5-1 (1999) is 6 mm or less. The hard coat film according to any one of claims 1 to 6,
A hard coat, wherein the inorganic compound layer is only partially peeled from the hard coat layer or better in an hourglass cross-cut peel test after laminating an inorganic compound layer on the film and boiled. the film. The hard coat film according to any one of claims 1 to 7,
The hard coat film, wherein the inorganic compound layer is an optical adjustment layer or a gas barrier layer. The hard coat film according to any one of claims 1 to 7,
The hard coat film, wherein the inorganic compound is SiO ₂ or Nb ₂ Ox (where 4 ≦ x ≦ 5). The hard coat film according to any one of claims 1 to 7,
The hard coat film, wherein the inorganic compound layer is composed of a single layer or multiple layers.   The transparent conductive film using the hard coat film as described in any one of Claim 1 to 10.   A touch panel using the hard coat film according to claim 1.

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