JP7061429B2 - A hard coat film for adhering an inorganic compound layer, and a transparent conductive film and a touch panel using the hard coat film. - Google Patents

Description

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

The electrode film used for the touch panel is created by forming an ITO (tin-doped indium oxide) film on the hard coat layer laminated on the surface of the transparent substrate by a sputtering method and forming an electrode pattern on the ITO film by etching. ..
Patent Document 1 discloses a technique of a hard coat film in which a transparent conductive layer such as ITO is formed on a hard coat layer, and these layers have good adhesiveness.
However, in the electrode film in which ITO is formed on the hard coat layer, the optical characteristics (transmittance, hue, reflectance, etc.) differ between the portion where the ITO film is present and the portion where ITO is removed, resulting in an electrode pattern. A phenomenon that makes it visible occurs, and the appearance becomes poor. Therefore, in recent years, the electrode film has come to have a structure in which an optical adjustment layer for adjusting optical characteristics is arranged between a hard coat layer and an ITO film. As a result, 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 Unexamined Patent Publication No. 2015-183168

As described above, in the electrode film having an optical adjustment layer between the hard coat layer and the ITO film, the optical adjustment layer is formed on the hard coat layer by a sputtering method, so that the adhesiveness with the optical adjustment layer is good. A film with a hard coat layer is required. In particular, in order to improve 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 well maintained.

Patent Document 1 discloses that the hard coat layer has good adhesion between the hard coat layer and ITO by blending a predetermined hydrophobic silica gel and a specific leveling agent, but the adhesiveness with the optical adjustment layer. Is neither disclosed nor suggested.

Therefore, an object of the present invention is to provide a hard coat film (hereinafter, "hard coat film") having a hard coat layer having improved adhesiveness to the inorganic compound layer. In particular, it is an object of the present invention to provide a hard-coated film that does not change with time and maintains good adhesiveness.

In the hard coat film of the present invention, an inorganic compound layer is adhered on the hard coat layer. The hardcoat layer contains 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 solid content of the binder resin.

Further, 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.

Further, in the hard coat film of the present invention, preferably, when the particles form secondary particles as aggregates of primary particles, the diameter of the primary particles is 1 nm or more and 100 nm or less.

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

Further, in the hard coat film of the present invention, the particles preferably 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.

Further, in the hard coat film of the present invention, 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.

Further, in the hard coat film of the present invention, preferably, in the hourglass cross-cut peeling test after laminating the inorganic compound layer on the film and boiling the film, the inorganic compound layer is only partially peeled off from the hard coat layer. No or better than that.

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

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

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

Further, the transparent conductive film of the present invention is characterized in that the above-mentioned hard coat film of the present invention is used.

Further, the touch panel of the present invention is characterized in that the above-mentioned hard coat film of the present invention is used.

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

(A) Cross-sectional view showing an example of an embodiment of the hard-coated film of the present invention, (b) Cross-sectional view showing another example of the embodiment of the hard-coated film of the present invention, (c) The hard-coated film of the present invention. Sectional drawing showing another example of embodiment Cross-sectional view showing an example of a hard coat film on which an inorganic compound layer is laminated Top view explaining the shape of the notch in the hourglass cross-cut peeling test (A) Cross-sectional view showing an example of a transparent conductive film to which the hard coat film of the present invention is applied, (b) Cross-sectional structure and transparent conductivity of (a) the transparent conductive film to which the transparent conductive film is etched. Diagram illustrating the reflected light of the film (a) Cross-sectional view of the hard coat film of the present invention in which the SiO ₂ film is laminated on the hard coat layer, (b) the Nb ₂ Ox (however 4 ≦ x ≦ 5) film and the SiO ₂ film are hard coated in this order. Sectional drawing of the hard coat film of this invention laminated on a layer

Hereinafter, embodiments of the hard coat film 1 for adhering the inorganic compound layer 40 of the present invention will be described with reference to FIGS. 1 to 5. The inorganic compound layer 40 may be a layer containing the inorganic compound or a layer of the inorganic compound itself as long as it is a layer having the inorganic compound.

The hard coat film 1 of the present invention has a hard coat layer 20, and contains particles (reactive modified particles) 21 modified so that the hard coat layer 20 has reactivity, and a binder resin 22, and the reactivity is modified. The content of the particles 21 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 22.

As a basic configuration, an embodiment of the present invention includes a support 10 and a hard coat layer 20 formed on the support 10, as shown in FIG. 1 (a). The hard coat film 1 may be a single-layer hard coat film (FIG. 1 (b)) as well as the one shown in FIG. 1 (a), or the hard coat layer 20 of the support 10 is formed. A backcoat layer (FIG. 1 (c)) may be provided on the surface opposite to the surface to be formed.

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 adhesiveness to the inorganic compound layer 40.

First, the reactive modifier 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 for the reactive modified particles 21 described later. It is desirable that the binder resin 22 has a reactive functional group. In that case, it can be effectively prevented from falling off of the reactive modified particles 21 by binding to the reactive functional group of the reactive modified particles 21. 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, an isocyanate group and the like.

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 can be used properly according to the purpose. Above all, when more excellent hardness is required, it is preferable to use an ionizing radiation curable resin.

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), and for example, one or two or more (meth) acryloyl groups in one molecule. Acryloyl resin having 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, silicone (meth) acrylate and the like. ..

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

Examples of the thermoplastic resin include polyester resin, acrylic resin, polycarbonate resin, cellulose resin, acetal resin, vinyl resin, polyethylene resin, polystyrene resin, polypropylene resin, polyamide resin, and polyimide resin. Examples include resins and fluororesins.

Further, it is more preferable that the binder resin 22 contains a certain amount of high molecular weight resin. By combining the high molecular weight resin and the reactive modified particles 21 described later, the hard coat layer 20 can be imparted with a certain degree of flexibility without impairing the hardness, and the inorganic compound layer 40 with respect to the hard coat layer 20 can be provided. The anchor effect is enhanced. As a result, the adhesiveness between the hard coat layer 20 and the inorganic compound layer 40 is further improved.
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, and more preferably 30,000 to 100,000.
As the high molecular weight resin, resins such as ionizing radiation curable resin, thermosetting resin, and thermoplastic resin can be used alone or in combination of two or more. Examples of the ionizing radiation curable resin, the thermosetting resin, and the thermoplastic resin are the same as those listed above as examples of the ionizing radiation curable resin, the thermosetting resin, and the thermoplastic resin of the binder resin 22.
The content is 1 part by weight or more and 50 parts by weight or less, more preferably 5 parts by weight or more and 40 parts by weight or less with respect to 100 parts by weight of the binder resin 22 (solid content). When the binder resin 22 contains a high molecular weight resin, the “binder resin 22 (solid content)” means the solid content of the entire binder resin 22 containing the high molecular weight resin.

The reactive modified particles 21 contribute to the improvement of the adhesiveness of the hard coat layer 20 to the inorganic compound layer 40 and the maintenance of the adhesiveness over time.
The reactive modified particles 21 are particles in which a reactive functional group is imparted to the surface of the inorganic particles by modifying the surface of the inorganic particles. The reactive functional group binds to the reactive functional group of the binder resin 22 to prevent the reactive modified particles 21 from falling off from the hard coat layer 20. Further, it is presumed that the adhesiveness with the inorganic compound layer can be maintained even in a high temperature and high humidity state by having a reactive functional group.
Examples of the 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, an isocyanate group and the like, and they can be used alone or in combination of two or more of these reactive functional groups. I can.

The content of the reactive modified particles 21 is such that the lower limit of the reactive modified particles 21 is 1 part by weight with respect to 100 parts by weight of the binder resin 22 (solid content) in order to exhibit the adhesiveness to the inorganic compound layer 40. As mentioned above, it is 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 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, and more preferably 30 parts by weight or less with respect to 100 parts by weight of the binder resin 22 (solid content). Is.
When the content of the reactive modified particles 21 is less than the above range, the adhesiveness with the inorganic compound layer 40 tends to be weakened. On the other hand, if it is more 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 which are aggregates as long as they have a predetermined size, but secondary particles are preferable in order to obtain more adhesiveness. It is not clear why the adhesiveness is improved when the secondary particles, which are aggregates of the primary particles, are used as the reactive modified particles 21 as compared with the case where the primary particles of the same size are simply used. It is considered that this is because the contact area of the particles protruding from the surface with the inorganic compound layer 40 increases.
The average particle size of the reactive modified particles 21 (including the primary particles or the secondary particles as aggregates composed of the primary particles) varies depending on the thickness of the hard coat layer 20, and therefore cannot be unequivocally determined, but the lower limit is 100 nm. As mentioned above, it is preferably 110 nm or more, and more preferably 130 nm or more. The upper limit is 1000 nm or less, preferably 800 nm or less, and more preferably 600 nm or less. Further, 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 which are the constituents of the secondary particles has a lower limit of 1 nm or more. It is preferably 20 nm or more, more preferably 30 nm or more. The upper limit is 100 nm or less, preferably 80 nm or less, and more preferably 60 nm or less.
The average particle size of the reactive modified particles 21 or, when the reactive modified particles 21 are composed of secondary particles, the average particle size of the primary particles is set to be equal to or more than the above-mentioned lower limit to improve the adhesiveness to the inorganic compound layer 40. Obtainable. On the other hand, by setting each of these average particle diameters to be equal to or less than the above-mentioned upper limit value, light transmission that can be used for transparent applications can be obtained.
The average particle size of the particles refers to the value of the volume average particle size (D50) that can be measured by the 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.
Examples of the photoinitiator include photoradical polymerization initiators such as acetophenones, benzophenones, Michler ketone, benzoin, benzylmethyl ketal, benzoylbenzoate, α-acyloxime ester, and thioxanthones, onium salts, sulfonic acid esters, and organic metal complexes. Examples thereof include photocationic polymerization initiators such as.
Further, as the curing agent, compounds such as polyisocyanate, amino resin, epoxy resin, and carboxylic acid can be appropriately used according to the compatible resin.

In the hard coat layer 20, in addition to the above-mentioned binder resin, polymer resin, reactive modifying particles, photoinitiator, and curing agent, antistatic agents, dispersants, and flocculants, as long as the performance is not impaired, It may further contain additives such as UV absorbers, antioxidants and leveling agents.

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, when the hard coat film 1 includes the support 10. It is preferably 1.0 to 3.0 μm. When the hard coat film 1 includes 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, and more preferably 1.0 to 3.0 μm. Is. Having such a thickness improves the adhesiveness between the hard coat layer 20 and the inorganic compound layer 40.
In the case of a hard coat layer single layer, the thickness thereof is 0.1 to 10.0 μm, preferably 0.5 to 5.0 μm, and more preferably 1.0 to 3.0 μm. By setting the thickness to 0.1 μm or more, the coating film strength is sufficient and the handleability is good while having adhesiveness to the inorganic compound layer 40.
The thickness of the hard coat layer 20 is measured using a reflection spectroscopic 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 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 compounds and the like can be used. Of these, a polyethylene terephthalate film that has been stretched, particularly biaxially stretched, is preferable because it is excellent in mechanical strength and dimensional stability. Further, in order to improve the adhesiveness with the hard coat layer 20, those having a corona discharge treatment on the surface or provided with an easy-adhesive layer are also preferably used. The thickness of the support 10 is usually preferably about 6 to 250 μm, more preferably about 23 to 188 μm.
The support 10 preferably has light transmittance, and specifically, the total light transmittance (JISK7136) is 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. 1 (c)) on the surface of the support 10 opposite to the hard coat layer 20.
In that 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 above-mentioned hard coat layer 20 may be provided.

The method for producing the hard coat film 1 is not particularly limited, but for example, when the support 10 is provided, a coating liquid for a hard coat layer in which the material of the hard coat layer 20 described above is dissolved or dispersed in an appropriate solvent is bar-coated. It can be produced by applying it on a support by a known method as described above, drying it, and irradiating it with ultraviolet rays as needed. Further, by forming the release layer on the support 10 in advance, the hard coat layer 20 is formed on the support 10, and then the support 10 is peeled off and removed from the hard coat layer single layer. Can be a film. Further, in the case of the hard coat film 1 having the back coat layer 30, the back coat of the support 10 provided with the hard coat layer 20 is dissolved or dispersed in an appropriate solvent on the surface opposite to the hard coat layer 20. It can be produced by applying a layer coating liquid on a known method such as bar coating, drying it, and irradiating it with ultraviolet rays as needed.

Next, the characteristics of the hard coat layer 20 will be described. The properties that the hardcourt layer 20 should have are adhesiveness 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 boiling treatment which is an accelerated weather resistance test (hereinafter referred to as "initial adhesiveness test"). , "Post-boiling adhesiveness test"), an hourglass cross-cut peeling test can be performed, and the superiority or inferiority can be determined and evaluated based on the results. As will be described later, in the hourglass cross-cut peeling test, the surface of the inorganic compound layer 40 is cross-cut into an hourglass-like shape for peeling, so that the adhesiveness is more severe than the cross-cut in a grid pattern. The superiority or inferiority of can be evaluated.

Here, the initial adhesiveness test method (hourglass cross-cut peeling test method) is as follows.

Inorganic compounds (for example, SiO ₂ , Nb ₂ Ox (however, 4 ≦ x ≦ 5), etc.) are sputtered on the hard-coated film 1 to prepare a test piece in which an inorganic compound layer 40 having a thickness of about 200 nm is formed (test). Piece manufacturing process).

Next, as shown in FIG. 3, a notch is made in the surface of the inorganic compound layer 40 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 each other, one end of the line segment FF'and GG' intersects the line segment DD', and the other end of the line segment FF'and GG'is a line, respectively. A notch is made on the surface of the inorganic compound layer 40 so as to intersect the line segment EE'. At this time, a notch is made so that the two triangles ABC and AB'C'formed by the line segments DD', EE', FF'and GG' become isosceles triangles having an apex angle of 30 degrees and a height of 1 cm. .. Here, the point where the line segment FF'and the line segment GG' intersect is defined as the apex A, and the intersections of the line segment GG'and the line segment FF' on the line segment DD'are designated as points B and C, respectively, and the line segment EE. Let the intersections of the line segment GG and the line segment FF'on the'up points B'and C', respectively (cutting step).

Adhesive tape (Nichiban Co., Ltd., cellophane tape (registered trademark)) is adhered so as to cover the two isosceles triangles with cuts, and the adhered adhesive tape is pulled apart at a predetermined angle and speed (first peeling). .. Then, using a newly prepared adhesive tape on the test piece after the first peeling, the same peeling test is performed again at the same place where the first peeling was performed (second peeling). In addition, except for the above-mentioned cutting method and continuous peeling at the same place twice, the cross-cut method specified in JIS K5600-5-6 is used (peeling step).

Tested according to the initial adhesiveness test method, in the present invention, the adhesiveness 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 all in the second peeling. Having such adhesiveness improves the adhesiveness to the inorganic compound layer 40 over time.

Further, in the post-boiling adhesiveness test method, after the test piece manufacturing step in the initial adhesiveness test method described above and before the cutting step, the test piece obtained in the test piece manufacturing step is subjected to pure water at a predetermined time. It differs from the initial adhesiveness test method in that it has a step of boiling treatment using it (boiling treatment step).
In the boiling treatment step, when the inorganic compound layer 40 is SiO ₂ , it is boiled for 6 hours. When the inorganic compound layer 40 is Nb ₂ Ox (however, 4 ≦ x ≦ 5), it is boiled for 1 hour.

Tested according to the post-boiling adhesiveness test method, in the present invention, the adhesiveness of the hardcourt layer is such that the inorganic compound layer 40 is only partially peeled off from the hardcourt layer 20 in the first or second peeling. Or better than that, better than one in which the inorganic compound layer 40 is only partially peeled from the hardcourt layer 20 in the first or second peeling, in the second peeling. It is more preferable that 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 adhesiveness test and the post-boiling adhesiveness test method are combined, in the present invention, the adhesiveness of the hard coat layer 20 is such that the inorganic compound layer 40 is hard coated by the second peeling of the initial adhesiveness test. It is preferable that the inorganic compound layer 40 is not peeled off from the layer 20 at all and the inorganic compound layer 40 is only partially peeled off from the hard coat layer 20 in the first peeling of the adhesiveness test after boiling. The inorganic compound layer 40 was not peeled off from the hard coat layer 20 at all in the second peeling, and the inorganic compound layer 40 was only partially peeled off from the hard coat layer 20 in the second peeling of the adhesiveness test after boiling. Good ones are more preferable than none.
By having such adhesiveness, even in a harsh environment such as high temperature and high humidity, the change with time is 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. The value of the bending resistance test differs depending on the material and thickness of the hard coat layer 20, or the type and thickness of the support 10 and the back coat layer 30 when the hard coat film 1 has the support 10 and the back coat layer 30. As a support, a PET film "KFL10W" manufactured by Teijin DuPont Co., Ltd. with an easy-adhesive film having a thickness of 125 μm is used, and a bending resistance test is conducted under the condition that a layer other than the easy-adhesive layer is not laminated on the back surface.
In the present invention, the value of the bending resistance test (diameter of the iron bar at which the hard coat layer cracks or peels 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 adhesiveness to the inorganic compound layer 40 can be improved. The value of the bending resistance test is a value measured by the cylindrical mandrel method based on JIS-K5600-5-1 (1999).

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

As an optical property of the hard coat film 1, the total light transmittance (JISK7136) is preferably 85% or more, more preferably 90% or more. By providing such light transmission, it is possible to impart adhesiveness to the inorganic compound layer 40 without disturbing the visibility of the 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. By adjusting the content according to the average particle size of the particles, a suitable haze can be maintained.

Next, an application example of the hard coat film 1 will be described by taking the hard coat film 1 having the structure shown in FIG. 1 (a) as an example.
FIG. 2 shows an example of the hard coat film (laminated body) 2 on which the inorganic compound layer 40 is laminated. The laminated body 2 becomes a laminated body 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 on the hard coat layer 20, the hard coat film 1 is used for the film 3 with the optical adjustment layer (FIG. 2). Further, as shown in FIG. 4A, the transparent conductive film 60 is further laminated on the optical adjustment layer 50, so that the hard coat film 1 of the present embodiment can be used for the transparent conductive film 4. 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 capacitance type or resistance 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 , Nb ₂ Ox (however, 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, for example, an Nb ₂ Ox (however, 4 ≦ x ≦ 5) film and a SiO ₂ film are laminated on the hard coat layer 20 in that order as shown in FIG. 5 (b). Lamination of SiO ₂ and Nb ₂ Ox (however, 4 ≦ x ≦ 5) may be performed by a conventionally known method, and a film is formed by a sputtering method or a thin film deposition method.

Examples of the transparent conductive film 60 include a film made of tin-doped indium oxide (ITO), zinc oxide (ZnO), aluminum-doped zinc oxide (AZO), an alloy of silver, copper or copper, carbon nanotubes, and the like. The layering of the transparent conductive film 60 may be performed 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 in a capacitive touch panel, the transparent conductive film 60 formed into a film is etched to form a desired electrode pattern (FIG. 4 (b)).
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 has the light 71 reflected by the ITO removal portion and the light reflected by the ITO remaining portion. The difference in optical characteristics (reflection, hue, transmittance, etc.) from 70 is reduced to make the ITO electrode pattern difficult to see.

On the other hand, when the gas barrier layer 51 is laminated on the hard coat layer 20, the hard coat film 1 is used for the gas barrier film 5 suitable for EL displays, EL lighting, solar cells and the like (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 from the viewpoint of workability and cost. The gas barrier layer 51 may be laminated on the hard coat layer 20 by a conventionally known method, and a film is formed by a sputtering method or a vapor deposition method.

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

Hereinafter, examples of the protective film of the present invention will be described. In the following examples, unless otherwise specified, "%" and "part" are both based on weight.

<Example 1>
A hard coat coating solution of the following formulation is applied to one surface of a 125 μm-thick polyethylene terephthalate film (KFL10W manufactured by Teijin DuPont), dried, and then cured by irradiating with ultraviolet rays to form a 2.0 μm-thick hard coat layer. The hard-coated film of Example 1 was produced.

<Coating liquid for hard coat>
・ Binder resin 30 parts of ionizing radiation curable resin (Unidic 17-813: DIC Corporation, solid content 80%)
15 parts of high molecular weight resin (Acridic A195: DIC Corporation, solid content 40%)
(Weight average molecular weight: 85000)
15 parts of reactive modified particle dispersion (SIRMIBK30WT% -M06: CIK Nanotech, solid content 30%)
(Silica particles: average primary particle diameter 30 nm, average secondary particle diameter 200-300 nm)
・ 60 parts of diluting solvent ・ 0.4 parts of photoinitiator (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 portion of the reactive modified particles was changed to 30 in the hard coat coating liquid of Example 1.

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

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

The following characteristics were evaluated for the protective films produced in the above-mentioned Examples and Comparative Examples.

1. 1. Optical characteristics According to the JISK7136 measurement method, use a haze meter (Suga Test Instruments Co., Ltd., model HGM-2K) and a color computer (Suga Test Instruments Co., Ltd., model SM-4) to use the hard coat layer of each protective film as the light input surface. Light transmittance (Tt) and haze (Haze) were measured.

3. 3. Regarding "bending resistance", based on the bending resistance (cylindrical mandrel method) based on JIS-K5600-5-1 (1999), iron bars with diameters of about 3 mm and 7 mm are prepared, and each iron bar is used. The protective film with a hard coat layer is folded back and wound so that the hard coat layer 20 is on the outside, and it is visually observed whether or not cracks or peeling from the support occur in the hard coat layer 20 of the wound portion. As a result, cracks or peeling from the support could not be confirmed with the 3 mm iron bar as "○", and cracks or peeling from the support could be confirmed with the 3 mm iron bar, but cracks or peeling from the support with the 7 mm iron bar. Those in which peeling from the horizontal bar could not be confirmed were evaluated as "Δ", and those in which cracks or peeling from the support were confirmed in both iron bars were evaluated as "x".

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

Next, as shown in FIG. 3, a notch was made in the surface of the inorganic compound layer 40 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 each other, one end of the line segment FF'and GG' intersects the line segment DD', and the other end of the line segment FF'and GG'is a line, respectively. A notch was made on the surface of the inorganic compound layer 40 so as to intersect the line segment EE'. At this time, a notch is made so that the two triangles ABC and AB'C'formed by the line segments DD', EE', FF'and GG' become isosceles triangles with an apex angle of 30 degrees and a height of 1 cm. rice field. Here, the point where the line segment FF'and the line segment GG' intersect is defined as the apex A, and the intersections of the line segment GG'and the line segment FF' on the line segment DD'are designated as points B and C, respectively, and the line segment EE. The intersections of the line segment GG and the line segment FF'on the line segment were set to points B'and C', respectively (cutting step).

Adhesive tape (Nichiban Co., Ltd., cellophane tape (registered trademark)) was adhered so as to cover the two isosceles triangles with cuts, and the adhered adhesive tape was pulled apart at a predetermined angle and speed (first peeling). ). Then, the test piece after the first peeling was subjected to the same peeling test again at the same place where the first peeling was performed using a newly prepared adhesive tape (second peeling). It should be noted that the process was performed in accordance with the cross-cut method specified in JIS K5600-5-6, except for the above-mentioned cutting method and continuous peeling at the same place twice (peeling step).

In this peeling test, those in which the inorganic compound layer 40 is not peeled off from the hard coat layer 20 at all (without peeling) are marked with ○ (without peeling), and those in which the inorganic compound layer 40 is partially peeled off from the hard coat layer 20 are marked with Δ (partially peeled off). ), The inorganic compound layer 40 completely peeled off from the hard coat layer 20 was evaluated as x (total peeling).

5. Post-boil Adhesiveness Test Method When the inorganic compound layer is SiO ₂ , the test piece was boiled in pure water for 6 hours after the test piece preparation step of the initial adhesiveness test described above (boiling treatment step). Next, the cutting step and the peeling process described above were performed, and the inorganic compound layer 40 was not peeled off from the hard coat layer 20 at all (no peeling), and the inorganic compound layer 40 was partially peeled off from the hard coat layer 20. Those in which the inorganic compound layer 40 was almost completely peeled off from the hard coat layer 20 were designated as Δ (with partial peeling), and those in which the inorganic compound layer 40 was almost completely peeled off were designated as × (total peeling).
When the inorganic compound layer is Nb ₂ Ox (however, 4 ≦ x ≦ 5), the test and evaluation are carried out in the same manner as in the case of SiO ₂ described above except that the boiling time is 1 hour in the boiling treatment step described above. gone.

The results are shown in Table 1.

Regarding the evaluation of adhesiveness, the adhesiveness to SiO ₂ and Nb ₂ Ox (however, 4 ≦ x ≦ 5) in the initial adhesiveness test on the films of Experimental Examples 1 to 3 was “no peeling” in the first and second peeling. "Met. Further, the adhesiveness to SiO ₂ in the post-boiling adhesiveness test of these examples was "no peeling" in the first peeling, "partially peeled" or "no peeling" in the second peeling, and Nb ₂ Ox (provided that it was not peeled). The adhesiveness to 4 ≦ x ≦ 5) was “no peeling” in both the first and second peeling except for Example 1.
On the other hand, the evaluation of the adhesiveness of the film of Comparative Example 1 to SiO ₂ and Nb ₂ Ox (however, 4 ≦ x ≦ 5) was inferior to that of Examples 1 to 3 in the initial adhesiveness test, and the adhesiveness test after boiling was performed. Then it was "all peeling".
These results show that the films of Examples 1 to 3 having the reactive modified particles 21 are less likely to change with time even in a harsh environment such as high temperature and humidity, and can maintain the initial adhesiveness to the inorganic compound layer 40. Indicated.

Regarding flexibility, Examples 1 to 3 had more flexibility than Comparative Example 1. Therefore, it was found that the hard coat layer 20 has appropriate flexibility, so that the adhesiveness to the inorganic compound layer 40 is improved.

1 ... hard coat film, 20 ... hard coat layer, 21 ... reactive modified particles, 22 ... binder resin, 40 ... inorganic compound layer, 50 ... optical adjustment layer, 51.・ ・ Gas barrier layer

Claims (11)

A hardcoat film having a hardcoat layer for adhering an inorganic compound layer.
The hardcourt layer contains particles modified to have reactivity and a binder resin.
The particles include aggregates in which primary particles are aggregated, and the average particle diameter of the particles containing the aggregates is 110 nm or more and 1000 nm or less, and the content thereof is 10 with respect to 100 parts by weight of the binder resin solid content. More than 40 parts by weight and less than 40 parts by weight
A hard coat film having a bending resistance test value of 6 mm or less measured by a cylindrical mandrel method according to JIS-K5600-5-1 (1999). The hard-coated film according to claim 1 .
A hard-coated film characterized in that the diameter of the primary particles is 1 nm or more and 100 nm or less. The hard-coated film according to claim 1 or 2 .
A hard coat film characterized in that the particles are silica, alumina, titanium, zirconia, calcium carbonate, magnesium carbonate, barium sulfate, or a combination of two or more thereof. The hard-coated film according to any one of claims 1 to 3 .
A hard coat film characterized in that 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-coated film according to any one of claims 1 to 4 .
In an hourglass cross-cut peeling test after laminating SiO ₂ on the film and boiling it for 6 hours, the layer of SiO ₂ is characterized in that it is only partially peeled off from the hardcourt layer or better. Hard coat film. The hard-coated film according to any one of claims 1 to 4 .
In the hourglass cross-cut peeling test after laminating Nb ₂ Ox (however, 4 ≦ x ≦ 5) on the film and boiling for 1 hour, the layer of Nb ₂ Ox was only partially peeled off from the hard coat layer. A hardcourt film characterized by being better than that. The hard-coated film according to any one of claims 1 to 6 .
The hardcoat film is characterized in that an optical adjustment layer or a gas barrier layer is provided as the inorganic compound layer . The hard-coated film according to any one of claims 1 to 6 .
The hard coat layer is a hard coat layer characterized in that a layer made of SiO ₂ or Nb ₂ Ox (provided, 4 ≦ x ≦ 5) is provided as the inorganic compound layer . The hard-coated film according to any one of claims 1 to 6 .
The hard coat layer is a hard coat film characterized by being provided with an inorganic compound layer composed of a single layer or multiple layers . A transparent conductive film using the hard coat film according to any one of claims 1 to 9 . A touch panel using the hard-coated film according to any one of claims 1 to 9 .

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