KR102382380B1 - Resin film, laminated film, optical member, display member, front plate, and method for producing laminated film - Google Patents

Abstract

A laminated film provided with the resin film containing a polyimide-type polymer|macromolecule, and the functional layer provided in at least one main surface side of the resin film is disclosed. A resin film containing a polyimide-based polymer and a silicon material containing silicon atoms and having Si/N, which is an atomic ratio of silicon atoms and nitrogen atoms, on at least one main surface of 8 or more, is also disclosed.

Description

Resin film, laminated film, optical member, display member, front plate, and manufacturing method of laminated film {RESIN FILM, LAMINATED FILM, OPTICAL MEMBER, DISPLAY MEMBER, FRONT PLATE, AND METHOD FOR PRODUCING LAMINATED FILM}

The present invention relates to a resin film, a laminated film, an optical member, a display member, a front plate, and a manufacturing method of the laminated film.

BACKGROUND ART Conventionally, glass has been used as a base material for various display members such as solar cells or displays. However, glass has the fault that it is brittle and is heavy, and in recent display thinning, weight reduction, and flexibility, WHEREIN: It did not necessarily have sufficient material characteristic. Therefore, as a material instead of glass, an acrylic resin and a laminated film in which scratch resistance is imparted to the resin have been studied. Further, a composite material of an organic material and an inorganic material such as a hybrid film containing polyimide and silica has also been studied (see, for example, Patent Documents 1 and 2).

Patent Document 1: Japanese Patent Laid-Open No. 2008-163309 Patent Document 2: Specification of US Patent No. 8207256

The laminated film which has a well-known acrylic resin as a base material, and has the functional layer provided on a base material was not necessarily sufficient in the point of flexibility to use as a display member or a front plate of a flexible device.

Then, one side of this invention aims at providing the laminated|multilayer film excellent in flexibility.

Moreover, in order to use a laminated|multilayer film as a display member or a front plate of a flexible device, it is also calculated|required that it has favorable visibility at the time of bending. However, even if it is a laminated|multilayer film which has the outstanding flexibility, the change of contrast and color may generate|occur|produce at the time of bending|flexion.

Then, another aspect of this invention aims at improving the visibility at the time of bending about the laminated|multilayer film which has a functional layer.

In order to use a hybrid film containing a polyimide-based polymer and silica as a flexible member, in general, it is necessary to form a functional layer having various functions such as an optical adjustment function and an adhesion function on the hybrid film. However, when a functional layer was formed on a hybrid film, there existed a case where the adhesiveness of a functional layer and a hybrid film was not necessarily enough.

Then, another aspect of this invention aims at providing the resin film excellent in adhesiveness with various functional layers, and laminated|multilayer film using the same.

According to the present invention, a front plate for an optical member, a display member, and a flexible device using a laminated film is also provided.

The laminated|multilayer film which concerns on 1 aspect of this invention are equipped with the resin film (resin base material) containing a polyimide-type polymer|macromolecule, and the functional layer provided on the main surface side of at least one of the said resin films.

The laminated|multilayer film which concerns on 1 aspect of this invention WHEREIN: Silica particle|grains may be sufficient as the said silicon material.

When a light irradiation test in which the laminated film is irradiated with light of 313 nm from the side of the functional layer for 24 hours with a light source having an output of 40 W provided at a distance of 5 cm from the laminated film according to one aspect is performed, the laminated film The following conditions may be satisfied:

(i) the laminated film after the light irradiation test has a transmittance of 85% or more with respect to light of 550 nm;

(ii) The said laminated|multilayer film before a light irradiation test has a yellowness of 5 or less, and the difference of the yellowness before and behind the light irradiation test of the said laminated|multilayer film is less than 2.5.

The said resin film after a light irradiation test may have a haze of 1.0 % or less.

In the laminated film which concerns on one aspect|mode of this invention, the said functional layer may be a layer which has at least 1 sort(s) of function selected from the group of ultraviolet absorption, surface hardness, adhesiveness, color adjustment, and refractive index adjustment.

The laminated|multilayer film which concerns on 1 aspect of this invention WHEREIN: The said functional layer may be a layer which has the function of at least any one of ultraviolet absorption and surface hardness.

A resin film according to an aspect of the present invention contains a polyimide-based polymer and a silicon material including silicon atoms. 8 or more may be sufficient as Si/N which is an atomic ratio of a silicon atom and a nitrogen atom in at least one main surface of this resin film. Silica particles may be used as the silicon material.

The laminated film which concerns on one aspect of this invention is equipped with the resin film which concerns on one aspect of this invention, and the functional layer provided in the main surface side of Si/N of the said resin film 8 or more.

The laminated|multilayer film which concerns on 1 aspect of this invention WHEREIN: A primer layer may be provided between the said resin film and the said functional layer. The said primer layer may contain the silane coupling agent. The said silane coupling agent may have at least 1 sort(s) of substituent chosen from the group which consists of a methacryl group, an acryl group, and an amino group.

The optical member which concerns on one aspect|mode of this invention is equipped with the laminated|multilayer film of this invention. The display member which concerns on one aspect|mode of this invention is equipped with the laminated|multilayer film of this invention. A front plate according to an aspect of the present invention includes the laminated film of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the laminated|multilayer film excellent in flexibility can be provided. The laminated|multilayer film of this invention can have functions, such as transparency, ultraviolet-ray-resistant characteristic, and surface hardness required when applying to the optical member, a display member, or a front plate of a flexible device. ADVANTAGE OF THE INVENTION According to this invention, the laminated film excellent in the visibility at the time of bending can be provided.

ADVANTAGE OF THE INVENTION According to this invention, the resin film excellent in adhesiveness with various functional layers, the laminated|multilayer film using this resin film, and the manufacturing method of laminated|multilayer film can be provided. The present invention can also provide an optical member, a display member, and a front plate using the laminated film. The resin film obtained by this invention can have the outstanding transparency and flexibility.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows the resin film of 1st Embodiment.
It is a schematic sectional drawing which shows the laminated|multilayer film of 2nd Embodiment.
It is a schematic sectional drawing which shows the laminated|multilayer film of 3rd Embodiment.
4 is a schematic cross-sectional view showing an example of a display device.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail. However, this invention is not limited to the following embodiment.

[First embodiment]

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows the resin film of this embodiment. The resin film 10 of this embodiment contains a polyimide-type polymer|macromolecule, and has a pair of main surface 10a, 10b which opposes.

The polyimide-based polymer contained in the resin film 10 may be polyimide. The polyimide is, for example, a condensed polyimide obtained by polycondensation using diamines and tetracarboxylic dianhydride as starting materials. As the polyimide-based polymer, one that is soluble in the solvent used for forming the resin film may be selected.

There is no restriction|limiting in particular as diamines, The aromatic diamines, alicyclic diamines, aliphatic diamines, etc. which are normally used for the synthesis|combination of a polyimide can be used. Diamines may be used independently and may use 2 or more types together.

As tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, acyclic aliphatic tetracarboxylic dianhydride, etc. can be used, There is no restriction|limiting in particular. Tetracarboxylic dianhydride may be used independently and may use 2 or more types together. Instead of tetracarboxylic dianhydride, a tetracarboxylic acid compound selected from analogs of tetracarboxylic acid compounds such as acid chloride compounds may be used as a starting material.

At least one of diamines and tetracarboxylic acid compounds (tetracarboxylic dianhydride) is at least one selected from the group consisting of a fluorine-based substituent, a hydroxyl group, a sulfone group, a carbonyl group, a heterocyclic ring, and a long-chain alkyl group having 1 to 10 carbon atoms. You may have one or a plurality of functional groups of the species. Among them, from the viewpoint of transparency, diamine and tetracarboxylic acid compound (tetracarboxylic dianhydride) may have a fluorine-based substituent introduced as a functional group. The fluorine-based substituent may be a group containing a fluorine atom, and specific examples thereof are a fluorine group (fluorine atom, -F) and a trifluoromethyl group.

From the viewpoint of solubility in a solvent, transparency and flexibility when the resin film 10 is formed, as the tetracarboxylic acid compound, an alicyclic tetracarboxylic acid compound (such as an alicyclic tetracarboxylic dianhydride) or an aromatic tetra A carboxylic acid compound (such as aromatic tetracarboxylic dianhydride) can be used. From the viewpoint of transparency of the resin film and suppression of coloration, as the tetracarboxylic dianhydride, an alicyclic tetracarboxylic acid compound or an aromatic tetracarboxylic acid compound having a fluorine-based substituent can be used.

As diamines, aromatic diamine, alicyclic diamine, and aliphatic diamine may be used independently and may use 2 or more types together. From the viewpoint of solubility in a solvent, transparency when the resin film 10 is formed, and flexibility, as diamines, alicyclic diamine or aromatic diamine can be used. From the viewpoint of transparency of the resin film and suppression of coloring, as diamines, alicyclic diamines or aromatic diamines having a fluorine-based substituent can be used.

When a polyimide-based polymer is used, it has particularly excellent flexibility, has high light transmittance (eg, 85% or more or 88% or more with respect to light at 550 nm) and low yellowness (YI value, such as 5 or less or 3 or less); It is easy to obtain a resin film of low haze (for example, 1.5% or less or 1.0% or less).

The polyimide may have a repeating structural unit represented by the following formula (PI). Here, G is a tetravalent organic group, and A is a divalent organic group.

Examples of G include a tetravalent organic group selected from the group consisting of an acyclic aliphatic group, a cyclic aliphatic group and an aromatic group. G may be a cyclic aliphatic group or an aromatic group. Examples of the aromatic group include a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed polycyclic aromatic group having two or more aromatic rings and connected to each other directly or by a bonding group. From the viewpoint of transparency of the resin film and suppression of coloration, G may be a cyclic aliphatic group or may be a cyclic aliphatic group, monocyclic aromatic group, condensed polycyclic aromatic group or non-condensed polycyclic aromatic group having a fluorine-based substituent. More specifically, a saturated or unsaturated cycloalkyl group, a saturated or unsaturated heterocycloalkyl group, an aryl group, a heteroaryl group, an arylalkyl group, an alkylaryl group, a heteroalkylaryl group, and any two groups thereof (which may be the same) and a group in which they are connected to each other directly or by a bonding group. Examples of the bonding group include -O-, an alkylene group having 1 to 10 carbon atoms, -SO ₂ -, -CO- or -CO-NR- (R is an alkyl group having 1 to 3 carbon atoms, such as a methyl group, an ethyl group, or a propyl group, or a hydrogen atom. represents) can be mentioned. The number of carbon atoms of G is usually 2 to 32, and may be 2 to 27, 5 to 10, 6 to 8, or 3 to 8. When G is a cyclic aliphatic group or an aromatic group, a part of carbon atoms may be substituted with a hetero atom. Examples of G are saturated or unsaturated cycloalkyl groups, saturated or unsaturated heterocycloalkyl groups, which may have 3 to 8 carbon atoms. Examples of the hetero atom include O, N and S.

Specifically, G may be a group represented by the following formulas (20), (21), (22), (23), (24), (25), or (26). * in the formula represents a bond. Z is a single bond, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -Ar-O-Ar-, -Ar-CH ₂ -Ar-, -Ar-C(CH ₃ ) ₂ -Ar- or -Ar-SO ₂ -Ar-. Ar represents an aryl group having 6 to 20 carbon atoms, an example of which is a phenylene group (benzene ring). At least one of the hydrogen atoms in these groups may be substituted with a fluorine-based substituent.

Examples of A include a divalent organic group selected from the group consisting of an acyclic aliphatic group, a cyclic aliphatic group and an aromatic group. The divalent organic group represented by A may be a cyclic aliphatic group or an aromatic group. Examples of the aromatic group include a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed polycyclic aromatic group having two or more aromatic rings and connected to each other directly or by a bonding group. From the viewpoint of transparency of the resin film and suppression of coloring, a fluorine-based substituent may be introduced into at least a part of A.

More specifically, A is a saturated or unsaturated cycloalkyl group, a saturated or unsaturated heterocycloalkyl group, an aryl group, a heteroaryl group, an arylalkyl group, an alkylaryl group, a heteroalkylaryl group, and any two groups thereof (the same also good) and they are linked to each other directly or by a bonding group. Examples of the hetero atom include O, N and S. Examples of the bonding group include -O-, an alkylene group having 1 to 10 carbon atoms, -SO ₂ -, -CO- and -CO-NR- (R is an alkyl group having 1 to 3 carbon atoms, such as a methyl group, an ethyl group, or a propyl group, or a hydrogen atom. shown) can be mentioned.

Carbon number of the divalent organic group represented by A is 2-40 normally, and 5-32, 12-28, or 24-27 may be sufficient as it.

Specifically, A may be a group represented by the following Formula (30), Formula (31), Formula (32), Formula (33), or Formula (34). In the formula, * represents a bond. Z ¹ , Z ² and Z ³ are each independently a single bond, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -SO ₂ -, -CO- or -CO-NR-( R represents an alkyl group having 1 to 3 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a hydrogen atom). In the following groups, it is preferable that Z ¹ and Z ² and Z ² and Z ³ each have a meta-position or a para-position with respect to each ring. In addition, it is preferable that the single bond at the terminal with Z ¹ , the single bond at the terminal with Z ² , and the single bond at the terminal with Z ³ exist in a meta site or a para site. One example is that Z ¹ and Z ³ are —O—, and Z ² is —CH ₂ —, —C(CH ₃ ) ₂ — or —SO ₂ —. At least one of the hydrogen atoms in these groups may be substituted with a fluorine-based substituent.

In at least one of A or G, at least one hydrogen atom is selected from the group consisting of a fluorine-containing substituent such as a fluorine group and a trifluoromethyl group, a hydroxyl group, a sulfone group, an alkyl group having 1 to 10 carbon atoms, etc. It may be substituted with 1 type of functional group. When A and G each represent a cyclic aliphatic group or an aromatic group, at least one of A or G may have a fluorine-based substituent, and both A and G may have a fluorine-based substituent.

Polyimide-type polymer|macromolecule may be a polymer containing at least 1 sort(s) of the repeating structural unit represented by Formula (PI), Formula (a), Formula (a'), or Formula (b). In formula (a), G ² represents a trivalent organic group, and A ² represents a divalent organic group. In formula (a'), G ³ represents a tetravalent organic group, and A ³ represents a divalent organic group. In formula (b), G ⁴ and A ⁴ each represent a divalent organic group.

G ² in the formula (a) can be selected from the same groups as G in the formula (PI) except for the point that it is a trivalent group. For example, G ² may be a contribution in which any one of the four bonds in the group represented by the formulas (20) to (26) exemplified as specific examples of G is substituted with a hydrogen atom. A ² in formula (a) can be selected from the same group as A in formula (PI).

G ³ in formula (a') can be selected from the same group as G in formula (PI). A ³ in the formula (a') can be selected from the same group as A in the formula (PI).

G ⁴ in the formula (b) can be selected from the same groups as G in the formula (PI) except for the point that it is a divalent group. For example, G ⁴ may be a contribution in which any two of the four bonds in the group represented by the formulas (20) to (26) exemplified as specific examples of G are substituted with hydrogen atoms. A ⁴ in formula (b) can be selected from the same group as A in formula (PI).

The polyimide-based polymer, which is a polymer including at least one repeating structural unit represented by formula (PI), formula (a), formula (a′) or formula (b), is a diamine, a tetracarboxylic acid compound, or a tri Condensation-type polymer|macromolecule obtained by polycondensing at least 1 type among carboxylic acid compounds (including tricarboxylic acid compound analogs, such as an acid chloride compound and tricarboxylic acid anhydride) may be sufficient. As a starting material, in addition to these, a dicarboxylic acid compound (including analogs such as an acid chloride compound) may be further used. The repeating structural unit represented by Formula (a') is derived from diamines and a tetracarboxylic-acid compound normally. The repeating structural unit represented by Formula (a) is normally derived from diamines and a tricarboxylic acid compound. The repeating structural unit represented by Formula (b) is normally derived from diamines and a dicarboxylic acid compound. Specific examples of diamines and tetracarboxylic acid compounds are as described above.

Examples of the tricarboxylic acid compound include an aromatic tricarboxylic acid, an alicyclic tricarboxylic acid, an acyclic aliphatic tricarboxylic acid, an acid chloride compound of these, and an acid anhydride. The tricarboxylic acid compound may be an acid chloride compound of an aromatic tricarboxylic acid, an alicyclic tricarboxylic acid, an acyclic aliphatic tricarboxylic acid, or an analog thereof. A tricarboxylic acid compound may use 2 or more types together.

From a viewpoint of the solubility to a solvent, transparency at the time of forming the resin film 10, and a flexible viewpoint, a tricarboxylic acid compound can be selected from an alicyclic tricarboxylic acid compound and an aromatic tricarboxylic acid compound. From the viewpoint of transparency of the resin film and suppression of coloring, the tricarboxylic acid compound may contain an alicyclic tricarboxylic acid compound having a fluorine-based substituent and an aromatic tricarboxylic acid compound having a fluorine-based substituent.

Examples of the dicarboxylic acid compound include aromatic dicarboxylic acid, alicyclic dicarboxylic acid, acyclic aliphatic dicarboxylic acid, and their derivative acid chloride compounds, acid anhydrides, and the like. The dicarboxylic acid compound may be an acid chloride compound of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, acyclic aliphatic dicarboxylic acid, or an analog thereof. You may use 2 or more types together of a dicarboxylic acid compound.

From a viewpoint of the solubility to a solvent, transparency at the time of forming the resin film 10, and a flexible viewpoint, a dicarboxylic acid compound can be selected from an alicyclic dicarboxylic acid compound and an aromatic dicarboxylic acid compound. From the viewpoint of transparency of the resin film and suppression of coloring, the dicarboxylic acid compound can be selected from an alicyclic dicarboxylic acid compound having a fluorine-based substituent and an aromatic dicarboxylic acid compound having a fluorine-based substituent.

Polyimide-type polymer|macromolecule may be a copolymer containing the several said repeating unit of a different kind. The weight average molecular weight of polyimide-type polymer|macromolecule is 10,000-500,000 normally. The weight average molecular weight of the polyimide-based polymer may be 50,000 to 500,000, 100,000 to 500,000, or 70,000 to 400,000. A weight average molecular weight is the standard polystyrene conversion molecular weight measured by GPC. When the weight average molecular weight of the polyimide-based polymer is large, high flexibility tends to be easily obtained.

The polyimide-based polymer may contain a halogen atom such as a fluorine atom that can be introduced by the above-described fluorine-based substituent or the like. When the polyimide-based polymer contains a halogen atom, the elastic modulus of the resin film can be improved and yellowness can be reduced. Thereby, it can suppress that a wound, a wrinkle, etc. generate|occur|produce in a resin film, and can improve transparency of a resin film. For example, a fluorine atom can be introduced into a molecule of a polyimide (polyimide-based polymer) by using a compound having a fluorine-based substituent such as a fluorine group or a trifluoromethyl group as at least one of diamines and tetracarboxylic dianhydride. can Content of the halogen atom (or fluorine atom) in a polyimide may be 1 mass % - 40 mass %, or 1 mass % - 30 mass % on the basis of the mass of polyimide-type polymer|macromolecule.

The resin film 10 may further contain inorganic materials, such as an inorganic particle. The inorganic material may be a silicon material containing a silicon atom. When the resin film 10 contains inorganic materials, such as a silicon material, the effect especially excellent in a flexible point is acquired.

As a silicon material containing a silicon atom, silicon compounds, such as quaternary alkoxysilanes, such as a silica particle and tetraethyl orthosilicate (TEOS), etc. are mentioned. The silicon material may be silica particles from the viewpoint of transparency and flexibility of the resin film 10 .

The average primary particle diameter of the silica particles may be 10 nm to 100 nm, or 20 nm to 80 nm. Transparency tends to improve that the average primary particle diameter of a silica particle is 100 nm or less. When the average primary particle diameter of the silica particles is 10 nm or more, the strength of the resin film tends to be improved and the cohesive force of the silica particles tends to be weakened, and thus handling tends to be easy.

The (average) primary particle diameter of the silica particle in a resin film can be calculated|required by observation by a transmission electron microscope (TEM). The particle distribution of the silica particle before forming a resin film can be calculated|required with a commercially available laser diffraction type particle size distribution meter.

In the resin film 10, the mixing ratio of the polyimide and the inorganic material (silicon material) may be 1:9-10:0 or 1:9-9:1, 3:7-10:0 or 3:7-8:2 may be sufficient. The mixing ratio may be 3:7 to 8:2 or 3:7 to 7:3. The ratio of the inorganic material with respect to the total mass of a polyimide and an inorganic material is 20 mass % or more normally, and 30 mass % or more may be sufficient. This ratio is usually 90 mass % or less, and 70 mass % or less may be sufficient as it. Transparency and mechanical strength of a resin film tend to improve that the compounding ratio of a polyimide and an inorganic material (silicon material) is in the said range.

The resin film 10 may further contain components other than a polyimide and an inorganic material (silicon material) in the range which does not impair transparency and flexibility remarkably. As components other than a polyimide and an inorganic material (silicon material), antioxidant, a mold release agent, a stabilizer, a bluing agent, a flame retardant, a lubricant, and a leveling agent are mentioned, for example. With respect to the mass of the resin film 10, 20 mass % or less may be sufficient as the ratio of the sum total of a polyimide and an inorganic material exceeds 0 %, and 10 mass % or less may be sufficient as it.

When the resin film 10 contains a polyimide and a silicon material, 8 or more may be sufficient as Si/N which is the atomic ratio of the silicon atom with respect to the nitrogen atom in at least one main surface 10a. This atomic ratio (Si/N) is obtained by evaluating the composition of the main surface 10a by X-ray Photoelectron Spectroscopy (XPS), and from the amount of silicon atoms and nitrogen atoms obtained by this. is the value that is calculated.

When Si/N in the main surface 10a of the resin film 10 is 8 or more, sufficient adhesiveness with the functional layer 20 mentioned later is acquired. From an adhesive viewpoint, Si/N may be 9 or more, or 10 or more may be sufficient as it. Si/N is usually 50 or less, and may be 40 or less.

Although the thickness of the resin film 10 is suitably adjusted according to the flexible device to which the laminated|multilayer film 30 is applied, 10 micrometers - 500 micrometers, 15 micrometers - 200 micrometers, or 20 micrometers - 100 micrometers may be sufficient. The resin film 10 having such a configuration can have particularly excellent flexibility.

Next, an example of the manufacturing method of the resin film 10 of this embodiment is demonstrated.

A solvent-soluble polyimide polymerized using a known polyimide synthesis method is dissolved in a solvent to prepare a polyimide varnish. The solvent may be any solvent that dissolves the polyimide, for example, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), γ-butyrolactone (GBL) ), or a combination thereof (mixed solvent).

In the case of producing a resin film containing an inorganic material (silicon material), the inorganic material is then added to a polyimide-based polymer varnish, stirred and mixed according to a known stirring method, and the silicon material is uniformly dispersed. to prepare

The mixing ratio of the polyimide and the inorganic material in the polyimide-based polymer varnish or dispersion may be 1:9 to 9:1 or 3:7 to 8:2 by mass.

The polyimide-based polymer varnish or dispersion may further contain an additive. Additives are, for example, selected from antioxidants, mold release agents, stabilizers, bluing agents, flame retardants, lubricants and leveling agents. The polyimide-based polymer varnish or dispersion may contain a compound such as an alkoxysilane having one or two or more metal alkoxide groups that contributes to bond formation between inorganic particles (such as silica particles). By using the dispersion liquid containing such a compound, the mixing|blending ratio of an inorganic particle can be enlarged, maintaining optical properties, such as transparency of a resin film. An example of such a compound is an alkoxysilane having an amino group.

Next, the dispersion is applied to a substrate according to a known roll-to-roll or arrangement method, for example, to form a coating film. The coating film is dried to form a film. Then, the resin film 10 is obtained by peeling a film from a base material. The substrate may be, for example, a polyethylene terephthalate (PET) substrate, a SUS belt, or a glass substrate.

For drying and/or baking of the coating film, the coating film may be heated. The coating film can be suitably heated at a temperature of 50°C to 350°C under conditions of an inert atmosphere or reduced pressure. The solvent can be evaporated by heating the coating film. You may form a resin film according to the method including drying a coating film at 50 degreeC - 150 degreeC, and baking the coating film after drying at 180 degreeC - 350 degreeC.

Next, you may surface-treat to at least one main surface of a resin film. UV ozone treatment may be sufficient as surface treatment. By UV ozone treatment, Si/N can be easily made into 8 or more. However, the method of making Si/N 8 or more is not limited to UV ozone treatment. The main surface 10a and/or 10b of the resin film 10 may be subjected to a surface treatment such as plasma treatment or corona discharge treatment to improve adhesion with a functional layer described later.

UV ozone treatment can be performed using a well-known ultraviolet light source containing a wavelength of 200 nm or less. As an example of an ultraviolet light source, a low pressure mercury lamp is mentioned. As an ultraviolet light source, you may use various commercially available apparatus provided with an ultraviolet light source. As a commercially available apparatus, the ultraviolet (UV) ozone cleaning apparatus UV-208 by the Technovision company is mentioned, for example.

The resin film 10 of this embodiment obtained in this way is excellent in flexibility. Moreover, in at least one main surface 10a, when Si/N which is an atomic ratio of a silicon atom and a nitrogen atom is 8 or more, the outstanding adhesiveness with the functional layer 20 mentioned later is acquired.

[Second embodiment]

Hereinafter, with reference to FIG. 2, the laminated|multilayer film which concerns on 2nd Embodiment are demonstrated.

It is a schematic sectional drawing which shows the laminated|multilayer film of this embodiment. In FIG. 2, the same code|symbol is attached|subjected to the component similar to the resin film of 1st Embodiment shown in FIG. 1, and the description is abbreviate|omitted.

The laminated|multilayer film 30 of this embodiment is comprised generally from the resin film 10 and the functional layer 20 laminated|stacked on one main surface 10a of the resin film 10. As shown in FIG.

The functional layer 20 may be a layer for further imparting a function (performance) to the laminated film 30 when using the laminated film 30 as an optical member, a display member, or a front plate of a flexible device. The functional layer 20 may be a layer having at least one function selected from the group consisting of ultraviolet absorption, surface hardness, adhesion, color adjustment, and refractive index adjustment.

As the functional layer 20, a layer having a function of absorbing ultraviolet rays (ultraviolet ray absorbing layer) includes, for example, a main material selected from an ultraviolet curable transparent resin, an electron beam curable transparent resin, and a thermosetting transparent resin, and dispersed in the main material. It consists of a UV absorber. By providing an ultraviolet absorption layer as the functional layer 20, the change of yellowness by light irradiation can be suppressed easily.

Although the ultraviolet curing type, electron beam curing type, or thermosetting type transparent resin as a main material of an ultraviolet absorption layer is not specifically limited, For example, poly(meth)acrylate may be sufficient.

The ultraviolet absorber may contain, for example, at least one compound selected from the group consisting of a benzophenone-based compound, a salicylate-based compound, a benzotriazole-based compound, and a triazine-based compound.

In this specification, a "system compound" refers to the derivative of the compound to which the said "system compound" is attached. For example, a "benzophenone-type compound" refers to a compound having a benzophenone as a parent skeleton and a substituent bonded to the benzophenone. This is also the same for other "system compounds".

The ultraviolet absorption layer may be a layer that absorbs 95% or more of light having a wavelength of 400 nm or less (eg, light having a wavelength of 313 nm). In other words, the ultraviolet absorbing layer may be a layer having a transmittance of less than 5% of light having a wavelength of 400 nm or less (eg, light having a wavelength of 313 nm). The ultraviolet absorbing layer may contain an ultraviolet absorbing agent having such a concentration that the transmittance is obtained. From the viewpoint of suppressing increase in the yellowness of the laminated film due to light irradiation, the ratio of the ultraviolet absorber in the ultraviolet absorption layer (functional layer 20) is usually 1% by mass or more based on the mass of the ultraviolet absorption layer. , 3 mass % or more may be sufficient. This ratio is normally 10 mass % or less, and 8 mass % or less may be sufficient.

As the functional layer 20, the layer (hard coat layer) having a function of surface hardness (a function of expressing high hardness on the surface) is, for example, a surface having a pencil hardness higher than that of the surface of the resin film as a laminated film. It is a layer given to 2H or more may be sufficient as the pencil hardness of the surface of a hard-coat layer, for example. Although this hard-coat layer is not specifically limited, Resin of the ultraviolet curing type, electron beam curing type, or thermosetting type typified by poly(meth)acrylates is included. The hard coat layer may contain a photoinitiator and an organic solvent. Poly(meth)acrylates, for example, are formed of one or more (meth)acrylates selected from polyurethane (meth)acrylate, epoxy (meth)acrylate, and other polyfunctional poly(meth)acrylates, It is a poly(meth)acrylate containing the monomer unit derived from these monomers. The hard-coat layer may contain inorganic oxides, such as a silica, an alumina, and polyorganosiloxane other than the said component.

As the functional layer 20, the layer (adhesive layer) having an adhesive function has a function of bonding the laminated film 30 to another member. As a material for forming the pressure-sensitive adhesive layer, a commonly known material can be used. For example, a thermosetting resin composition or a photocurable resin composition can be used.

The adhesion layer may be comprised from the resin composition containing the component which has a polymerizable functional group. In this case, strong adhesion is realizable by further polymerizing the resin composition which comprises an adhesive layer after making the laminated|multilayer film 30 closely_contact|adherent to another member. 0.1 N/cm or more or 0.5 N/cm or more may be sufficient as the adhesive strength of the resin film 10 and an adhesion layer.

The adhesion layer may contain the thermosetting resin composition or the photocurable resin composition as a material. In this case, the resin composition can be polymerized and cured by supplying energy afterwards.

The pressure-sensitive adhesive layer may be a layer that is adhered to the object by pressing, called a pressure sensitive adhesive (PSA). The pressure-sensitive adhesive may be an adhesive that is "a substance that has tack at room temperature and adheres to an adherend with light pressure" (JIS K6800), "a specific component is contained in a protective film (microcapsule), and suitable means A capsule adhesive may be used which is an adhesive capable of maintaining stability until the film is destroyed by (pressure, heat, etc.)” (JIS K6800).

As the functional layer 20 , the layer having a color adjustment function (color adjustment layer) is a layer capable of adjusting the laminated film 30 to a desired color. The color adjustment layer is, for example, a layer containing a resin and a colorant. Examples of the colorant include inorganic pigments such as titanium oxide, zinc oxide, bengala, titanium oxide calcined pigments, ultramarine blue, cobalt aluminate, and carbon black; Organic compounds such as azo compounds, quinacridone compounds, anthraquinone compounds, perylene compounds, isoindolinone compounds, phthalocyanine compounds, quinophthalone compounds, threne compounds and diketopyrrolopyrrole compounds pigment; extender pigments such as barium sulfate and calcium carbonate; Dyes, such as a basic dye, an acid dye, and a mordant dye, are mentioned.

The layer (refractive index adjustment layer) which has a function of refractive index adjustment as the functional layer 20 has a refractive index different from the resin film 10, and is a layer which can provide a predetermined|prescribed refractive index to laminated|multilayer film. The refractive index adjusting layer may be, for example, a resin layer further containing an appropriately selected resin and optionally a pigment, or may be a thin metal film.

Examples of the pigment for adjusting the refractive index include silicon oxide, aluminum oxide, antimony oxide, tin oxide, titanium oxide, zirconium oxide, and tantalum oxide. The average particle diameter of the pigment may be 0.1 µm or less. When the average particle diameter of the pigment is 0.1 µm or less, diffuse reflection of the light passing through the refractive index adjusting layer can be prevented, and a decrease in transparency can be prevented.

Examples of the metal used for the refractive index adjusting layer include metal oxides or metal nitrides such as titanium oxide, tantalum oxide, zirconium oxide, zinc oxide, tin oxide, silicon oxide, indium oxide, titanium oxynitride, titanium nitride, silicon oxynitride, and silicon nitride. can be heard

The functional layer 20 has the said function suitably according to the use of the laminated|multilayer film 30. The functional layer 20 may be a single layer or a plurality of layers may be sufficient as it. Each layer may have one function or two or more functions.

The functional layer 20 may have the functions of surface hardness and ultraviolet absorption. The functional layer 20 in this case is "a single layer having the functions of surface hardness and ultraviolet absorption", "a multilayer comprising a layer having surface hardness and a layer having ultraviolet absorption", or "surface hardness and ultraviolet absorption. A single layer having a function and a multilayer including a layer having surface hardness” may be included.

Although the thickness of the functional layer 20 is suitably adjusted according to the flexible device to which the laminated|multilayer film 30 is applied, 1 micrometer - 100 micrometers, or 2 micrometers - 80 micrometers may be sufficient, for example. The functional layer 20 is typically thinner than the resin film 10 .

The laminated film 30 can be obtained by forming the functional layer 20 on the main surface 10a of the resin film 10 . The functional layer 20 can be formed according to a well-known roll-to-roll or arrangement|positioning method.

The ultraviolet absorption layer as the functional layer 20, for example, forms a coating film by coating a dispersion liquid containing a main material such as an ultraviolet absorber and a resin in which the ultraviolet absorber is dispersed on the main surface 10a of the resin film 10, and the It can be formed according to the method of drying and hardening a coating film.

The hard coat layer as the functional layer 20 is, for example, applied to the main surface 10a of the resin film 10 with a solution containing a resin forming the hard coat layer to form a coating film, and drying and curing the coating film. Depending on the method, it can be formed.

The adhesive layer as the functional layer 20 is, for example, a method of coating a solution containing an adhesive for forming an adhesive layer on the main surface 10a of the resin film 10 to form a coating film, and drying and curing the coating film. According to it, it can be formed.

The color adjustment layer as the functional layer 20 is, for example, on the main surface 10a of the resin film 10, a pigment forming the color adjustment layer, and a dispersion containing a main material such as a resin in which the pigment is dispersed. It can form according to the method of forming a coating film, and drying and hardening the coating film.

The refractive index adjusting layer as the functional layer 20 is, for example, on the main surface 10a of the resin film 10, inorganic particles forming the refractive index adjusting layer, and a dispersion containing a main material such as a resin in which the inorganic particles are dispersed. A coating film is formed by application|coating, and it can form according to the method of drying and curing the coating film.

As the functional layer 20, a single layer having a function of surface hardness and ultraviolet absorption is formed on the main surface 10a of the resin film 10, a main material such as a resin in which the ultraviolet absorber and the ultraviolet absorber are dispersed, and a hard coat layer. It can be formed according to the method of apply|coating the dispersion liquid containing the resin to form to form a coating film, and drying and hardening the coating film. Resin of the main material and resin which forms a hard-coat layer may be the same.

On the main surface 10a of the resin film 10, a dispersion liquid containing a main material such as an ultraviolet absorber and a resin in which the ultraviolet absorber is dispersed is applied to form a coating film, and by drying and curing the coating film, an ultraviolet absorption layer is formed, Then, you may form a hard-coat layer by apply|coating the solution containing the resin which forms a hard-coat layer to this ultraviolet-absorbing layer, forming a coating film, and drying and hardening the coating film. According to this method, a multi-layered functional layer comprising a layer having surface hardness and a layer having ultraviolet absorption is formed.

On the main surface 10a of the resin film 10, a dispersion liquid containing an ultraviolet absorber, a main material such as a resin in which the ultraviolet absorber is dispersed, and a resin for forming a hard coat layer is applied to form a coating film, and the coating film is dried and curing to form a single layer having the functions of surface hardness and ultraviolet absorption, and further, on the monolayer, a solution containing a resin for forming a hard coat layer is applied to form a coating film, and the coating film is dried and cured By making it, you may form a hard-coat layer. According to this method, a multi-layered functional layer comprising a layer having the functions of surface hardness and ultraviolet absorption and a layer having surface hardness is formed.

Thus, the laminated|multilayer film 30 of this embodiment obtained are excellent in a flexibility. The laminated film 30 may have functions such as transparency, UV resistance, and surface hardness required when applied to an optical member, a display member, or a front plate of a flexible device. When Si/N in the main surface 10a of the resin film 10 is 8 or more, it is excellent also in the adhesiveness of the resin film 10 and the functional layer 20.

When a light irradiation test in which the laminated film 30 is irradiated with light of 313 nm from the side of the functional layer 20 for 24 hours with a light source having an output of 40 W provided at a distance of 5 cm from the laminated film 30 is performed , the laminated film 30 may satisfy the following conditions:

(i) the laminated film after the light irradiation test has a transmittance of 85% or more and a haze of 1.0% or less with respect to light of 550 nm;

(ii) The laminated film before the light irradiation test has a yellowness degree (YI value) of 5 or less, and the difference in yellowness before and behind the light irradiation test of the laminated film is less than 2.5.

The laminated|multilayer film which satisfy|fills these conditions (i) and (ii) are hard to generate|occur|produce a change in contrast or a hue at the time of a bending|flexion, and can maintain favorable visibility.

For example, a layer having a function of absorbing ultraviolet rays is provided as the functional layer 20, and further, as the resin film 10 and the functional layer 20, a transmittance of 85% or more and a haze of 1.0% or less with respect to light at 550 nm. When a film having a

90% or more may be sufficient as the transmittance|permeability with respect to 550 nm light of the laminated|multilayer film after a light irradiation test, 100% or less, or 95% or less may be sufficient as it. 0.9 or less or 0.1 or more may be sufficient as the haze of the laminated|multilayer film after a light irradiation test. The laminated|multilayer film before a light irradiation test may have the transmittance|permeability of 85% or more with respect to 550 nm light, and a haze value of 1.0 or less. The detail of the measuring method of transmittance|permeability and haze is demonstrated in the Example mentioned later.

4 or less, 3 or less may be sufficient as the yellowness of the laminated|multilayer film before a light irradiation test, and 0.5 or more may be sufficient as it. When the yellowness before and after the light irradiation test is YI ₀ and the yellowness after the light irradiation is YI ₁ , the difference (ΔYI) in the yellowness before and after the light irradiation test of the laminated film is in the formula: ΔYI=YI ₁ -YI ₀ is calculated according to It is preferable that ΔYI is 2.2 or less, 2.0 or less may be sufficient, and 0.1 or more may be sufficient as it. The detail of the measuring method of yellowness is demonstrated in the Example mentioned later.

In this embodiment, although the structure in which the functional layer 20 was laminated|stacked on one main surface 10a of the resin film 10 was illustrated, this invention is not limited to this. For example, the functional layer may be laminated|stacked on both surfaces of a resin film.

The laminated film 30 of this embodiment is used as an optical member, a display member, or a front plate of a flexible device, for example.

[Third embodiment]

Hereinafter, with reference to FIG. 3, the laminated|multilayer film which concerns on 3rd Embodiment are demonstrated.

It is a schematic sectional drawing which shows the laminated|multilayer film of this embodiment. In FIG. 3, the same code|symbol is attached|subjected to the component same or corresponding to the laminated|multilayer film of 2nd Embodiment shown in FIG. 2, and the description is abbreviate|omitted. The laminated film 30 of this embodiment is the resin film 10, the functional layer 20 provided in one main surface 10a side of the resin film 10, the resin film 10, and the functional layer 20 ) is roughly composed of a primer layer 25 provided between them. The primer layer 25 is laminated on one main surface 10a of the resin film 10 . The functional layer 20 is laminated on the main surface (hereinafter, sometimes referred to as "one main surface") 25a of the primer layer 25 on the opposite side to the main surface in contact with the resin film 10 .

The primer layer 25 is a layer formed from a primer agent, and it is preferable that the resin film 10 and the material which can improve adhesiveness with the functional layer 20 are included. The compound contained in the primer layer 25 may be chemically bonded to the polyimide-based polymer or silicon material contained in the resin film 10 at the interface.

Examples of the primer agent include a primer agent of an epoxy-based compound of an ultraviolet curing type, a heat curing type, or a two-component curing type. A polyamic acid may be sufficient as a primer agent. These are suitable in order to improve adhesiveness with the resin film 10 and the functional layer 20.

The primer agent may contain the silane coupling agent. The silane coupling agent may chemically bond with the silicon material contained in the resin film 10 by a condensation reaction. A silane coupling agent is especially useful, especially when the compounding ratio of the silicon material contained in the resin film 10 is high.

The silane coupling agent is a compound having a silicon atom and an alkoxysilyl group having 1 to 3 alkoxy groups covalently bonded to the silicon atom. The silane coupling agent may be a compound including a structure in which two or more alkoxy groups are covalently bonded to a silicon atom, or a compound including a structure in which three alkoxy groups are covalently bonded to a silicon atom. Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, and a t-butoxy group. Especially, a methoxy group and an ethoxy group can improve the reactivity with a silicon material.

The silane coupling agent may have a high affinity substituent with the resin film 10 and the functional layer 20 . From the viewpoint of affinity with the polyimide-based polymer contained in the resin film 10 , the substituent of the silane coupling agent may be an epoxy group, an amino group, a urea group, or an isocyanate group. When the functional layer 20 contains (meth)acrylates, if the silane coupling agent used for the primer layer 25 has an epoxy group, a methacryl group, an acryl group, an amino group, or a styryl group, affinity increases tends to Among these, the silane coupling agent which has a substituent selected from a methacryl group, an acryl group, and an amino group shows the tendency excellent in affinity with the resin film 10 and the functional layer 20 .

Although the thickness of the primer layer 25 is suitably adjusted according to the functional layer 20, 0.01 nm - 20 micrometers may be sufficient. When using the primer agent of an epoxy compound, the thickness of the primer layer 25 may be 0.01 micrometer - 20 micrometers, or 0.1 micrometer - 10 micrometers. When using a silane coupling agent, the thickness of the primer layer 25 may be 0.1 nm - 1 micrometer, or 0.5 nm - 0.1 micrometer.

Next, the manufacturing method of the laminated|multilayer film 30 of FIG. 3 of this embodiment is demonstrated.

First, it carries out similarly to 1st Embodiment, and produces the resin film 10. Next, according to a well-known roll-to-roll or arrangement|positioning method, the solution which melt|dissolved the primer agent is apply|coated to one main surface 10a of the resin film 10, and a 1st coating film is formed. You may harden a 1st coating film slightly as needed.

Next, it carries out similarly to 1st Embodiment, the raw material of the functional layer 20 is apply|coated on the 1st coating film, and a 2nd coating film is formed. By hardening a 1st coating film and a 2nd coating film simultaneously or individually, the primer layer 25 and the functional layer 20 are formed, and the laminated|multilayer film 30 is obtained.

Thus, the laminated|multilayer film 30 of this embodiment obtained are excellent in a flexibility. Since the primer layer 25 is provided between the resin film 10 and the functional layer 20, the adhesiveness of the resin film 10 and the functional layer 20 is high. The laminated film 30 may have functions such as transparency, UV resistance, and surface hardness required when applied to an optical member, a display member, and a front plate of a flexible device.

In this embodiment, the case where the functional layer 20 is provided on one main surface 10a side of the resin film 10, and the primer layer 25 is provided between the resin film 10 and the functional layer 20 Although illustrated, the present invention is not limited thereto. A functional layer may be laminated|stacked on both sides of a resin film through a primer layer.

[Fourth embodiment]

Hereinafter, a display device according to a fourth embodiment will be described with reference to FIG. 4 .

It is a schematic sectional drawing which shows an example of the display apparatus which is an application example of the laminated|multilayer film of this embodiment. The display device 100 of the present embodiment includes an organic EL device 50 , a touch sensor 70 , and a front plate 90 . These are usually accommodated in a case. The organic EL device 50 and the touch sensor 70 and between the touch sensor 70 and the front plate 90 are adhered, for example, with an optical adhesive (Optical Clear Adhesive, OCA).

The organic EL device 50 includes an organic EL element 51 , a first substrate 55 , a second substrate 56 , and a sealing material 59 .

The organic EL element 51 includes a pair of electrodes (a first electrode 52 and a second electrode 53 ) and a light emitting layer 54 . The light emitting layer 54 is disposed between the first electrode 52 and the second electrode 53 .

The first electrode 52 is formed of a light-transmitting conductive material. The second electrode 53 may also have light transmittance. As the 1st electrode 52 and the 2nd electrode 53, a well-known material is employable.

The light emitting layer 54 can be formed of a known light emitting material constituting the organic EL element. The light emitting material may be either a low molecular compound or a high molecular compound.

When electric power is supplied between the first electrode 52 and the second electrode 53 , carriers (electrons and holes) are supplied to the light emitting layer 54 , and light is generated in the light emitting layer 54 . Light generated from the light emitting layer 54 is emitted to the outside of the organic EL device 50 through the first electrode 52 and the first substrate 55 .

The first substrate 55 is formed of a material having light transmittance. The second substrate 56 may have light transmittance. The first substrate 55 and the second substrate 56 are joined by a sealing material 59 disposed so as to surround the periphery of the organic EL element. The first substrate 55 , the second substrate 56 , and the sealing material 59 form a sealing structure for sealing the organic EL element therein. The first substrate 55 and/or the second substrate 56 is a gas barrier material in many cases.

As a forming material for either or both of the first substrate 55 and the second substrate 56, an inorganic material such as glass or a known transparent resin such as an acrylic resin can be used. As these members, the laminated|multilayer film which concerns on this embodiment mentioned above can also be employ|adopted.

The 1st board|substrate 55 and the 2nd board|substrate 56 which can employ|adopt the laminated|multilayer film which concern on this embodiment correspond to the display member or gas barrier material in this embodiment. Since the laminated|multilayer film which concerns on this embodiment is employ|adopted for the organic electroluminescent apparatus 50 which has such the 1st board|substrate 55 and the 2nd board|substrate 56, it is excellent in flexibility.

The touch sensor 70 has a board|substrate 71 (touch sensor base material), and the element layer 72 which has the detection element formed on the board|substrate 71. As shown in FIG.

The substrate 71 is formed of a material having light transmittance. As the substrate 71, an inorganic material such as glass or a known transparent resin such as an acrylic resin can be used. As the board|substrate 71, the laminated|multilayer film which concerns on this embodiment mentioned above may be employ|adopted.

In the element layer 72, a known detection element composed of a semiconductor element, wiring, resistor, and the like is formed. As a structure of a detection element, the structure which implement|achieves a well-known detection method, such as a matrix switch, a resistive film type, and a capacitive type, is employable.

The board|substrate 71 which can employ|adopt the laminated|multilayer film which concerns on this embodiment corresponds to the optical member in this embodiment. Since the laminated|multilayer film which concerns on this embodiment is employ|adopted for the touch sensor 70 which has such a board|substrate 71, it is excellent in flexibility.

The front plate 90 is formed of a material having light transmittance. The front plate 90 is located in the outermost layer on the display screen side of the display device and functions as a protective member for protecting the display device. The front plate is sometimes called a window film. As the front plate 90, an inorganic material such as glass or a known transparent resin such as an acrylic resin can be used. As the front plate 90, the laminated|multilayer film which concerns on this embodiment mentioned above may be employ|adopted. When a laminated film is employed as the front plate 90 , the laminated film is usually arranged in a direction in which the functional layer is located outside the display device.

The front plate 90 to which the laminated|multilayer film which concerns on this embodiment can employ|adopt corresponds to the optical member in this embodiment. Since the laminated|multilayer film which concerns on this embodiment is employ|adopted for such a front plate 90, it is excellent in flexibility.

When the display device 100 employs the laminated film according to the present embodiment as one or more constituent members selected from the organic EL device 50, the touch sensor 70, and the front plate 90, excellent flexibility as a whole is obtained. can have That is, the display device 100 may be a flexible device.

The apparatus (flexible device) to which the laminated|multilayer film which concerns on this embodiment can be applied is not limited to the said display apparatus. For example, it is employable also in a solar cell which has a board|substrate on which the photoelectric conversion element was formed, and the front plate provided in the board|substrate surface. In this case, if the laminated|multilayer film which concerns on this embodiment is employ|adopted as a board|substrate or front plate of a solar cell, the solar cell can have the outstanding flexibility as a whole.

Example

Hereinafter, although an Example and a comparative example demonstrate this invention more concretely, this invention is not limited to the following Example.

-review 1-

Example 1

Based on a known document (eg, United States Patent; Patent No. US8,207,256B2), a resin film (silica particle content: 60 mass%) containing polyimide and silica particles was produced as follows.

The acid anhydride of the formula (1), the diamines of the formulas (2) and (3), a catalyst, and a solvent (γ-butyrolactone and dimethylacetamide) were placed in a polymerization tank substituted with nitrogen. Content was 75.0 g of acid anhydride of Formula (1), 36.5 g of diamine of Formula (2), 76.4 g of diamine of Formula (3), 1.5 g of catalyst, 438.4 g of (gamma) butyrolactone, and 313.1 g of dimethylacetamide. The molar ratio of the diamine of (2) Formula and the diamine of (3) Formula was 3:7, the diamine sum total, and the molar ratio of an acid anhydride was 1.00:1.02.

After stirring the mixture in the polymerization tank to dissolve the raw material in the solvent, the temperature of the mixture was raised to 100°C, and then the temperature was raised to 200°C and kept warm for 4 hours to polymerize the polyimide. During this heating, water in the liquid was removed. Then, the polyimide was obtained by refinement|purification and drying.

Next, a γ-butyrolactone solution of polyimide adjusted to a concentration of 20% by mass, a dispersion in which silica particles having a solid content concentration of 30% by mass are dispersed in γbutyrolactone, and a dimethylacetamide solution of an alkoxysilane having an amino group are mixed. , and stirred for 30 minutes.

Here, the mass ratio of a silica particle and a polyimide was 60:40, and the quantity of the alkoxysilane which has an amino group was 1.67 mass parts with respect to a total of 100 mass parts of a silica particle and a polyimide.

The mixed solution was apply|coated to a glass substrate, it heated at 50 degreeC for 30 minutes, and 140 degreeC for 10 minutes, and the solvent was dried. Then, the 80-micrometer-thick resin film was obtained by peeling a film from a glass substrate, attaching a metal frame, and heating at 210 degreeC for 1 hour.

On one side of the obtained resin film, a two-component curing primer (trade name: Aracoat 2510, manufactured by Arakawa Chemical Industry Co., Ltd.) is applied to form a coating film, the coating film is dried and cured, and a primer layer having a thickness of 1 µm was formed.

Next, on the primer layer, a solution for forming a functional layer is applied to form a coating film, and the coating film is dried and cured to form a 10 µm-thick functional layer (layer having a function of surface hardness and ultraviolet absorption), The laminated film of Example 1 was obtained. The solution for forming a functional layer contains 47.5 parts by mass of a tetrafunctional acrylate (trade name: A-TMMT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 47.5 parts by mass of a trifunctional acrylate (trade name: A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.); 12.5 parts by mass of reactive urethane polymer (trade name: 8BR-600, manufactured by Daisei Fine Chemicals, 40% by mass), 3 parts by mass of a triazine-based ultraviolet absorber (TINUVIN (registered trademark) 479, manufactured by BASF), a photopolymerization initiator (IRGACURE) (registered trademark) 184, manufactured by Chiba Specialty Chemicals) 8 parts by mass, 0.6 parts by mass of a leveling agent (trade name: BYK-350, manufactured by Big Chemi Japan) and 107 parts by mass of methyl ethyl ketone were mixed and stirred to prepare.

Comparative Example 1

On one main surface of a base material (PMMA film) made of polymethyl methacrylate (PMMA) having a thickness of 120 µm, a functional layer having a thickness of 10 µm was formed in the same manner as in Example 1, and the laminated film of Comparative Example 1 was got it

(Evaluation) Measurement of pencil hardness

The pencil hardness of the surface by the side of the functional layer of the laminated|multilayer film of Example 1 and Comparative Example 1 was measured based on JISK5600-5-4. The load in the measurement of pencil hardness was 1 kg. A result is shown in Table 1.

evaluation of flexibility

The laminated films of Example 1 and Comparative Example 1 were cut into the size of 1 cm x 8 cm. The surface of the functional layer of the laminated|multilayer film after a cut|disconnection was turned inside, it wound around the roll of radius (r)=1mm, and the presence or absence of the crack in laminated|multilayer film was confirmed. Flexibility was judged on the basis of the following criteria. A result is shown in Table 1.

A: It did not crack and maintained a good external appearance.

C: Five or more cracks arose.

Optical properties Yellowness (YI value)

The yellowness (Yellow Index: YI value) of the laminated|multilayer film of Example 1 and Comparative Example 1 was measured with the Nippon Bunko Ultraviolet-visible near-infrared spectrophotometer V-670. After carrying out the background measurement in the absence of a sample, the laminated|multilayer film was set in the sample holder, the transmittance|permeability with respect to 300 nm - 800 nm light was measured, and tristimulus values (X, Y, Z) were calculated|required. YI value was computed based on the following formula.

YI value=100×(1.28X-1.06Z)/Y

Optical properties were judged on the basis of the following criteria. A result is shown in Table 1.

A: YI value is less than 3

C: YI value is 3 or more

transmittance

The transmittance|permeability with respect to the light of 300 nm - 800 nm was measured using the UV-visible near-infrared spectrophotometer V-670 manufactured by Nippon Bunko. The transmittance was determined on the basis of the following criteria. A result is shown in Table 1.

A: The transmittance with respect to the light of the wavelength of 550 nm is 90% or more

C: Transmittance with respect to light of a wavelength of 550 nm is less than 90%

haze

The laminated|multilayer film was set in the sample holder with the fully automatic direct reading haze computer HGM-2DP by the Suga Shikenki company, and the haze of the laminated|multilayer film was measured. The haze was determined on the basis of the following criteria. A result is shown in Table 1.

A: Haze (%) is less than 1.0%

C: Haze (%) is 1.0% or more

Ultraviolet degradation accelerated test (QUV test, light irradiation test)

The laminated film was subjected to a QUV test using UVCON manufactured by Atras. The light source was UV-B 313 nm, the output was 40 W, and the distance between the sample (laminated film) and the light source was set to 5 cm. The laminated film was irradiated with ultraviolet rays from the functional layer side for 24 hours.

After UV irradiation, optical properties (YI value, transmittance) were evaluated as described above. A result is shown in Table 1.

From the result of Table 1, the laminated|multilayer film of Example 1 is excellent in flexibility. In addition, it turned out that the laminated|multilayer film of Example 1 has functionality, such as an ultraviolet-ray-resistant characteristic and surface hardness, and can utilize for the optical member of a flexible device, a display member, and a front plate.

-Review 2-

Example 2

Using the same polyimide as in Example 1, the gamma butyrolactone solution of the polyimide adjusted to the density|concentration of 20 mass % was prepared. This solution, the solution which disperse|distributed the silica particle with the solid content concentration of 30 mass % in (gamma) butyrolactone, the dimethylacetamide solution of the alkoxysilane which has an amino group, and water were mixed, and it stirred for 30 minutes.

Here, the mass ratio of silica particles to polyimide is 60:40, the amount of the alkoxysilane having an amino group is 1.67 parts by mass based on 100 parts by mass of the total of the silica particles and polyimide, and the amount of water is 100 parts by mass of the total of silica and polyimide. to 10 parts by mass.

Using the obtained mixed solution, it carried out similarly to Example 1, it had a resin film, a primer layer, and a functional layer, and obtained the laminated|multilayer film in which these were laminated|stacked in this order. However, the thickness of the functional layer was changed to 6 µm.

Example 3

A polyimide (“Neoprim” manufactured by Mitsubishi Chemical Co., Ltd.) having a glass transition temperature of 390°C was prepared. A γ-butyrolactone solution having a concentration of 20% by mass of this polyimide, a dispersion in which silica particles having a solid content concentration of 30% by mass are dispersed in γbutyrolactone, a dimethylacetamide solution of an alkoxysilane having an amino group, and water are mixed, 30 After stirring for a minute, a mixed solution was obtained. The mass ratio of the silica particles to the polyimide is 55:45, the amount of the alkoxysilane having an amino group is 1.67 parts by mass based on 100 parts by mass of the total of the silica particles and the polyimide, and the amount of water is 100 parts by mass of the total of the silica particles and the polyimide It was 10 mass parts with respect to a part. Using this mixed solution, it was carried out in the same manner as in Example 1 to obtain a laminated film of Example 3 having a resin film, a primer layer and a functional layer (thickness of 10 µm) and in which these were laminated in this order.

Comparative Example 2

The resin film of Example 2 before forming a primer layer and a functional layer was evaluated as a film of Comparative Example 2.

(Evaluation) optical properties

The films of Example 2 and Comparative Example 2 were subjected to the same QUV test (light irradiation test) as in Review 1. About the film before and behind a test, the transmittance|permeability, YI value, and haze were measured similarly to examination 1. The difference (ΔYI) in YI values before and after the test was also obtained. A result is shown in Table 2.

visibility

The film before the light irradiation test was bent, the state of external appearance, such as contrast and hue at that time, was confirmed, and the following reference|standards judged visibility. A result is shown in Table 2.

A: No change in contrast and color was observed.

C: Appearance changes such as changes in contrast and color were observed.

As shown in Table 2, the laminated film of Example 2 subjected to the light irradiation test satisfies the above-mentioned conditions (i) and (ii), and it was confirmed that this laminated film had high visibility at the time of bending. .

-Review 3-

Example 4

It carried out similarly to Example 1, and produced the 75-micrometer-thick resin film (silica particle content 60 mass %) containing a polyimide and a silica particle.

UV ozone treatment was performed on one main surface of the resin film. UV ozone treatment was performed for 15 minutes using the ultraviolet (UV) ozone washing|cleaning apparatus UV-208 manufactured by Technovision Corporation.

Next, on the main surface of the resin film subjected to UV ozone treatment, a silane coupling agent having an amino group (3-aminopropyltriethoxysilane, trade name: Z6011, manufactured by Toray Dow Corning) was applied to form a primer layer. .

Next, on the primer layer, a solution for forming a functional layer is applied to form a coating film, and the coating film is dried and cured to form a functional layer (layer having a function of surface hardness and ultraviolet absorption) having a thickness of 5 μm, The laminated|multilayer film of Example 3 was obtained. The solution for forming a functional layer contains 47.5 parts by mass of a tetrafunctional acrylate (trade name: A-TMMT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 47.5 parts by mass of a trifunctional acrylate (trade name: A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.); 12.5 parts by mass of reactive urethane polymer (trade name: 8BR-600, manufactured by Daisei Fine Chemicals, 40% by mass), 3 parts by mass of a triazine-based ultraviolet absorber (TINUVIN (registered trademark) 479, manufactured by BASF), a photopolymerization initiator ( IRGACURE (trademark) 184, manufactured by Chiba Specialty Chemicals) 8 parts by mass, 0.6 parts by mass of a leveling agent (trade name: BYK-350, manufactured by Big Chemi Japan) and 107 parts by mass of methyl ethyl ketone were mixed and stirred to prepare.

Reference example

It carried out similarly to Example 1, and produced the 75-micrometer-thick resin film (silica particle content 60 mass %) containing a polyimide and a silica particle.

Next, a silane coupling agent having an amino group (3-aminopropyltriethoxysilane, trade name: Z6011, manufactured by Toray Dow Corning) was applied to one main surface of the resin film to form a primer layer.

Next, the functional layer similar to Example 3 was formed on the primer layer, and the laminated|multilayer film of the reference example was obtained.

Evaluation of the surface composition of the resin film

The surface to which UV ozone treatment was performed in the resin film of Example 3 and one main surface of the resin film of the reference example were evaluated according to the X-ray photoelectron spectroscopy (XPS) method.

For the X-ray photoelectron spectroscopy, an X-ray photoelectron spectrometer (trade name: Quantera SXM, manufactured by ULVAC PHI) was used. X-rays were AlKa (1486.6 eV) and 100 µm in diameter. For charging correction, 1 eV electron gun and 10 eV Ar ion gun were used. The photoelectron extraction angle was 75 degrees.

Analysis software attached to the apparatus: Using Multipak V8.2C, the peak area of each element was calculated|required from the obtained XPS spectrum, and the quantity of each element in the film surface was computed in atom% unit from the peak area. Further, the atomic ratio (Si/N) of the silicon atom to the nitrogen atom was calculated from the Si2p peak and the N1s peak. A result is shown in Table 3.

haze

The method similar to examination 1 evaluated the haze (%) of laminated|multilayer film. A result is shown in Table 4.

As shown in Table 3, in the surface to which UV ozone treatment was performed in the resin film of Example 4, Si/N which is ratio of a silicon atom and a nitrogen atom was 8.3. On the other hand, in one surface of the resin film of a reference example, it turned out that Si/N is 6.5.

Evaluation of the adhesion of the functional layer

The cross-hatching test based on JIS-K5600-5-6 evaluated the adhesiveness of the functional layer in the laminated|multilayer film of an Example and a reference example. Make cuts in a grid pattern of 10 × 10 at intervals of 2 mm, attach scotch tape (registered trademark, manufactured by Nichiban), and count the number of grids remaining after peeling off the scotch tape in a direction 60° to the surface it was Adhesiveness was judged on the following reference|standard. A result is shown in Table 3.

A: The number of remaining grids is 100

C: The number of remaining grids is 99 or less

From the result of Table 5, the laminated|multilayer film of Example 4 showed that the adhesiveness of a functional layer was high, and the laminated|multilayer film of a reference example showed that the adhesiveness of a functional layer was low.

10… resin film, 20... functional layer, 25... Primer layer, 30... Laminated film, 50... Organic EL device, 70... Touch sensor, 90… Front panel, 100… display device.

Claims (8)

A laminated film comprising a resin film and a functional layer provided on at least one main surface side of the resin film,
The functional layer is a hard coat layer having a thickness of 1 μm to 10 μm and having a function of absorbing ultraviolet rays containing poly (meth) acrylate,
The functional layer is laminated on the one main surface of the resin film,
The resin film contains a polyimide-based polymer,
When a light irradiation test in which the laminated film is irradiated with light of 313 nm from the side of the functional layer for 24 hours with a light source having an output of 40 W provided at a distance of 5 cm from the laminated film, the laminated film is condition of:
(i) the laminated film after the light irradiation test has a transmittance of 85% or more with respect to light of 550 nm;
(ii) the laminated film before the light irradiation test has a yellowness of 5 or less, and the difference in yellowness of the laminated film before and after the light irradiation test is less than 2.5;
satisfy the
The thickness of the resin film is 20 to 80 ㎛,
The haze of the resin film is less than 1.0%,
The laminated film after the light irradiation test has a haze of 0.9% or less,
When the laminated film is cut to 1 cm × 8 cm and wound on a roll having a radius (r) = 1 mm with the surface of the functional layer inside, cracks do not occur in the laminated film,
A laminated film for flexible devices used as a front plate of a display device that is a flexible device (however, except for those containing a transparent electrode layer formed on one side of a polyimide-based film). The laminated film for flexible devices of Claim 1 in which the said resin film further contains the silicon material containing a silicon atom. The laminated film for flexible devices according to claim 2, wherein the silicon material is silica particles. The laminated film for flexible devices according to claim 1, further comprising a primer layer provided between the resin film and the functional layer, wherein the primer layer contains a silane coupling agent. The laminated film for flexible devices of Claim 4 in which the said silane coupling agent has at least 1 sort(s) of substituent chosen from the group which consists of a methacryl group, an acryl group, and an amino group. A front plate provided with the laminated|multilayer film in any one of Claims 1-5. delete delete

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