JPWO2015194324A1 - Complex - Google Patents

Abstract

An object of this invention is to provide the composite_body | complex which a crack is hard to generate | occur | produce when a tensile stress is applied with respect to the glass substrate in which the micro crack exists in the surface. In the present invention, the resin of the resin layer enters at least a part of the inside of the microcrack, and the ratio of the penetration depth df of the resin from the glass substrate surface to the depth d of the microcrack and the elongation at break of the resin layer The present invention relates to a composite in which the product of TE (%) and the yield stress σS (MPa) of the resin layer is 400 MPa ·% or more and the tensile elastic modulus of the resin layer is 1.0 GPa or more.

Description

  The present invention relates to a composite, and more particularly to a composite in which a resin enters a predetermined depth inside a microcrack on the surface of a glass substrate.

  As a substrate of an electronic device such as an image display panel, a solar battery, and a thin film secondary battery, a composite sheet having a glass sheet and a resin layer bonded to the glass sheet has been proposed (for example, see Patent Document 1). When the glass sheet included in the composite sheet is bent and deformed with a predetermined radius of curvature and a tensile stress is generated on the main surface of the glass sheet bonded to the resin layer, the tensile stress is reduced by the presence of the resin layer. Thereby, the breakage of the glass sheet can be suppressed.

International Publication No. 2012/166343

On the other hand, the glass substrate is usually subjected to various processes such as a cleaning process, a polishing process, and a cutting process, and microcracks are formed on the surface of the glass substrate.
With reference to the description of Patent Document 1, the present inventors formed a resin layer on a glass substrate that had been subjected to a predetermined treatment and formed microcracks on the surface, and evaluated the characteristics of the composite. However, it has been found that when a tensile stress is applied to the glass substrate, the glass substrate may be easily broken.

  In view of the above circumstances, an object of the present invention is to provide a composite that is unlikely to crack when a tensile stress is applied to a glass substrate having microcracks on the surface.

As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.
That is, the first embodiment of the present invention is a composite comprising a glass substrate having a microcrack on the surface and a resin layer disposed on the glass substrate, wherein at least a part of the inside of the microcrack is provided. resin enters the resin layer, wherein the microcracks to the depth d, the ratio of the resin enters the depth d _f of from the glass substrate surface and _(d f _/ d), elongation at break of the resin layer TE ( %) And the yield stress σ _S (MPa) of the resin layer (ratio (d _f / d) × breaking elongation TE × yield stress σ _S ) is 400 MPa ·% or more, and the resin layer It is a composite having a tensile elastic modulus E _resin of 1.0 GPa or more.
In the first embodiment, the average thickness of the glass substrate is preferably 10 to 200 μm.
In the first embodiment, the average thickness of the resin layer is preferably 10 to 100 μm.
In the first embodiment, the resin layer preferably contains polyimide.
The 2nd form of this invention is an electronic device containing the composite_body | complex which is a 1st form, and the element formed on the glass substrate of the said composite_body | complex.

  ADVANTAGE OF THE INVENTION According to this invention, the composite_body | complex which a crack is difficult to generate | occur | produce when a tensile stress is applied with respect to the glass substrate in which the surface has a microcrack can be provided.

FIG. 1 is a cross-sectional view showing one embodiment of the composite of the present invention. FIG. 2 is a plan view of a glass substrate having microcracks. FIG. 3 is a cross-sectional view showing the structure of an organic EL panel according to an embodiment of the present invention. FIG. 4 is a cross-sectional view illustrating a structure of a liquid crystal panel according to an embodiment of the present invention. FIG. 5 is a cross-sectional view illustrating the structure of a solar cell according to an embodiment of the present invention. FIG. 6 is a cross-sectional view showing the structure of a thin film secondary battery according to an embodiment of the present invention. FIG. 7 is a cross-sectional view showing the structure of electronic paper according to an embodiment of the present invention. FIG. 8 is a schematic view showing a bending test apparatus for examining the average fracture strength of a glass substrate and a composite according to an embodiment of the present invention. 9 (A) and 9 (B) are diagrams in which fluorescein is adsorbed on the surface of a glass substrate having microcracks, the glass substrate is broken, and the cross section is observed with an optical microscope (FIG. 9 (A)). ) And a diagram observed with a fluorescence microscope (FIG. 9B).

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and description thereof is omitted. In addition, the figure in this invention is a schematic diagram, and the relationship of the thickness of each layer, a positional relationship, etc. do not necessarily correspond with an actual thing. In the present specification, “wt%” and “mass%” are synonymous.
One of the features of the composite of the present invention is that the properties of the resin layer (breaking elongation, yield stress, tensile elastic modulus) are controlled, and the resin in the resin layer has a predetermined depth in the microcrack of the glass substrate. It is possible to get in. The cause of the glass substrate being easily broken is considered to be the presence of microcracks existing on the glass surface. When stress is applied to the glass, the microcracks are expected to develop and break. Therefore, as described above, a desired effect is obtained by the resin having predetermined characteristics entering the microcracks.

FIG. 1 is a schematic cross-sectional view of an example of a composite according to the present invention.
The composite 2 includes a glass substrate 4 and a resin layer 6 disposed on the glass substrate 4. There is a microcrack 8 on the surface of the glass substrate 4 on the resin layer 6 side, and the resin in the resin layer 6 enters at least part of the inside of the microcrack 8.
The composite 2 may be used as a substrate of an electronic device such as an image display panel, a solar battery, or a thin film secondary battery, and may be formed with various elements. The composite 2 may be wound around a winding core or used for manufacturing an electronic device by a roll-to-roll method.
In FIG. 1, the resin layer 6 is provided only on one side of the glass substrate 4, but the resin layer 6 may be provided on both sides of the glass substrate 4. The two resin layers 6 disposed across the glass substrate 4 may have the same thickness or different thicknesses, and may have different physical properties (tensile modulus, thermal expansion coefficient, etc.). It may have physical properties.

  First, in the following, the glass substrate 4 and the resin layer 6 constituting the composite 2 will be described in detail.

<Glass substrate>
The glass of the glass substrate 4 may be various, and examples thereof include soda lime glass and alkali-free glass.

The average thickness of the glass substrate 4 is not particularly limited, but is preferably 200 μm or less. If the average thickness of the glass substrate 4 is 200 μm or less, the glass substrate 4 can be spirally wound to produce a glass roll.
The average thickness of the glass substrate 4 is preferably 150 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. The average thickness of the glass substrate 4 is preferably 0.1 μm or more, more preferably 1 μm or more, further preferably 5 μm or more, and particularly preferably 10 μm or more.
In addition, the said average thickness is the value which measured the thickness of the arbitrary 10 or more glass substrates 4, and arithmetically averaged them.

  The thickness deviation in the width direction of the glass substrate 4 is preferably 5 μm or less. “Thickness deviation” means a deviation from the average thickness. If the thickness deviation in the width direction of the glass substrate 4 is 5 μm or less, the stress generated in the glass substrate 4 at the time of bending deformation of the composite 2 is uniform, and the damage of the glass substrate 4 can be reduced. The thickness deviation in the longitudinal direction of the glass substrate 4 is generally smaller than the thickness deviation in the width direction of the glass substrate 4. The thickness deviation in the width direction of the glass substrate 4 is more preferably 3 μm or less, further preferably 1 μm or less, and particularly preferably 0.5 μm or less. The thickness deviation in the width direction of the glass substrate 4 can be obtained by measuring the uneven shapes on the front and back surfaces of the glass substrate 4 with a laser displacement meter.

  The glass substrate 4 may be strip-shaped, and the width of the glass substrate 4 may be 100 mm or more. When the width of the glass substrate 4 is 100 mm or more, the tension applied to the composite 2 may be uneven in the width direction in the manufacturing process of the electronic device by the roll-to-roll method, and tensile stress is applied to a part of the glass substrate 4. May concentrate. In such a case, the effect of this embodiment (the effect of reducing breakage of the glass substrate 4) appears remarkably.

  The manufacturing method of the glass substrate 4 may be any of a float method, a fusion method, and a redraw method. In the float process, molten glass is flowed on molten tin in a bath and formed into a strip shape. After the formed glass is gradually cooled, the gradually cooled glass is cut into a desired size. In the fusion method, the molten glass overflowing from the bowl-shaped member is merged at the lower end of the bowl-shaped member to form a strip, and after cooling the molded glass, the slowly cooled glass is cut into a desired size. To do. In the redraw method, a glass substrate is softened with heat and then stretched to a desired thickness, and the stretched glass substrate is solidified.

  Microcracks 8 are present on the surface of the glass substrate 4. The microcracks 8 are generated during various processes (cleaning process, polishing process, cutting process, etc.) in manufacturing a glass substrate, or when handling the glass substrate. The shape of the microcrack 8 is not particularly limited, and as shown in FIG. 2 which is a plan view of the glass substrate 4 having the microcrack, for example, a shape 8a in which a groove-like recess extends linearly, A concave shape 8b is exemplified.

The micro crack 8 mainly intends a crack (scratch) of a micro size level or less.
The size of the depth d of the microcracks 8 is not particularly limited, but the range that can be detected by an electron microscope or the like is often 0.1 μm or more, and more often 1.0 μm or more. The upper limit is not particularly limited, but is often 30 μm or less, and more often 15 μm or less.
The size of the width W of the microcrack 8 is not particularly limited, but the range that can be detected by an electron microscope or the like is often 1 nm or more and more often 10 nm or more. The upper limit is not particularly limited, but is often 100 μm or less and more often 10 μm or less.
Examples of a method for measuring the depth d and the width W of the microcracks 8 include a method of cutting the composite 2 and observing the cross section with an electron microscope.

<Resin layer>
The resin layer 6 is a layer disposed on the glass substrate 4 and serves as a reinforcing layer that reinforces the fragility of the glass substrate 4.
The resin layer 6 satisfies the relationship of the following formula (1) with the glass substrate 4 described above.
Formula (1): (ratio (d _f / d)) × (breaking elongation TE of resin layer) × (yield stress σ _{S of} resin layer) ≧ 400 MPa ·%
Below, each item in these formula | equation is explained in full detail first.

As shown in FIG. 1, the resin in the resin layer 6 has entered (filled) into a partial region inside the microcrack 8. The ratio (d _f / d) of the resin penetration depth d _f (filling depth) from the surface of the glass substrate 4 to the micro crack depth d (resin embedding ratio in the micro crack depth direction) Is not particularly limited as long as the relationship of the above formula (1) is satisfied, but is preferably 0.01 or more in that the composite is more difficult to break (hereinafter, also simply referred to as “the effect of the present invention is more excellent”). 0.05 or more is more preferable, and 0.1 or more is more preferable. The upper limit is not particularly limited, because it is not the depth d _f enters than the depth d of the micro cracks increases, and 1 or less. The enter depth d _f, based on the glass substrate 4 surface, represents the deepest position of the resin intrudes into the interior microcracks.
The ratio (d f _{/ d)} is the average value, to observe 10 or more microcracks, measured and depth d _f enter the depth d at each of microcracks, the ratio of each microcracks ( d _f / d) is a value obtained by arithmetically averaging the calculated ratio (d _f / d) of each microcrack.

The depth d and the penetration depth _df are obtained by directly observing the fracture starting point with an optical microscope after carrying out a fracture test of the composite. In addition, theoretical values can also be obtained from the fracture stress / stress intensity factor from the basic equation of fracture mechanics (“Destructive Science of Ceramics” P68), and the certainty can be confirmed. In addition, for enters depth d _f, by previously dispersing the dye in the resin for coating, a fracture origin after breakdown test were observed under a fluorescence microscope, that the size can be measured and compared to the depth d Can do. Here, the dye is not particularly limited, but fluorescein and its derivatives are preferable.
Moreover, in the case of a resin liquid with poor dispersibility of the dye, a water-soluble resin having a combined viscosity can be used as the observation resin. By combining the viscosity of the resin layer forming composition used for actually forming the resin layer with the viscosity of the evaluation composition containing the observation resin and the dye, the evaluation composition is deep. The degree of penetration of d into the microcracks is about the same as when the resin layer forming composition is used. Here, the water-soluble resin refers to polyvinyl alcohol (PVA), hydroxycellulose (HEC), and the like. The depth d can also be determined by adsorbing a dye on the inner surface of the microcrack and observing the fracture starting point after the destructive test with a fluorescence microscope.

As an example, in FIG. 9A and FIG. 9B, a cross section of the glass substrate in the vicinity of the fracture start point after the fluorescein is adsorbed on the surface of the glass substrate having microcracks and subjected to a destructive test is obtained using an optical microscope. And the photograph observed with the fluorescence microscope is shown. FIG. 9A is an observation view with an optical microscope, and FIG. 9B is an observation view with a fluorescence microscope. The arrow in the figure intends the thickness direction of the glass substrate. Comparing the two, the fluorescence derived from fluorescein adsorbed inside the microcracks can be confirmed on one surface of FIG. 9B (the lower surface of the glass substrate in the drawing). The depth d can be calculated from the depth of the fluorescent region. Further, as described above, the penetration depth d is obtained by dispersing a pigment (for example, fluorescein) in the resin to be applied and observing the cross section of the glass substrate after the destructive test in the same manner as in FIG. 9B. _f can also be observed.

The magnitude of the breaking elongation TE (%) of the resin layer 6 is not particularly limited as long as the relationship of the above formula (1) is satisfied, but is preferably 20% or more, more preferably 40% or more in terms of more excellent effects of the present invention. More preferred.
The measuring method of breaking elongation TE (%) follows ASTM D882-12.

The magnitude of the yield stress σ _S (MPa) of the resin layer 6 is not particularly limited as long as the relationship of the above formula (1) is satisfied, but 50 MPa or more is preferable and 100 MPa or more is more preferable in terms of more excellent effects of the present invention. .
The measuring method of the yield stress σ _S conforms to JIS-C-2151: 2006.

In the above formula (1), the product of the ratio (d _f / d), the breaking elongation TE of the resin layer 6 and the yield stress σ _S of the resin layer 6 is 400 MPa ·% (N / mm ² · %) Or more. Among these, the left side of the above formula (1) ((ratio (d _f / d)) × (breaking elongation TE of the resin layer) × (yield stress σ _{S of the} resin layer) in that the effect of the present invention is more excellent. )) Is preferably 450 MPa ·% or more, and more preferably 500 MPa ·% or more. The upper limit is not particularly limited, but is usually 8000 MPa ·% or less, and more often 2000 MPa ·% or less.
As described above, the cause of the cracking of the glass substrate 4 is that the stress is concentrated on the microcracks 8 present on the surface of the glass substrate 4, so that the glass substrate 4 is easily broken. The inventors of the present invention enter the resin that can form the resin layer 6 exhibiting a predetermined breaking elongation TE and yield stress σ _S into a predetermined depth inside the microcrack 8, that is, the relationship of the formula (1). By satisfying the above, it has been found that the stress in the direction of further developing the cracks of the microcracks 8 as indicated by the white arrows in FIG. 1 can be suppressed.
More specifically, as described above, the reason why the glass substrate breaks is that stress concentrates on the microcrack, but when the resin enters (embeds) the microcrack, the energy applied to the microcrack enters. It is distributed to the resin according to the depth that is flowing. At that time, the work done by the resin is expressed by the following formula (X).

In formula (X), W ′ is the work done by the resin embedded in the microcracks, α is the resin embedding rate in the depth direction of the microcracks, d is the depth of the microcracks, and σ is the yield stress of the resin. , Ε represents the elongation at break of the resin.
Among the above variables, d (depth of microcrack) corresponds to the deepest microcrack corresponding to the minimum strength of the glass that has passed through a certain process. Can be considered. Then, it is α, σ, and ε that determine the magnitude of the work amount W ′. The present inventors have found that if the product of these three parameters is a predetermined value, the glass substrate is hardly cracked.
In particular, the greater the rupture elongation TE of the resin layer 6, the wider the allowable stress range until the resin inside the microcrack breaks. Further, the greater the yield stress σ _S of the resin layer 6, the wider the range of allowable stress until the resin inside the microcrack reaches yield.

The tensile elastic modulus E _resin of the resin layer 6 is 1.0 GPa or more, and 1.5 GPa or more is preferable and 2.0 GPa or more is more preferable in that the effect of the present invention is more excellent. The upper limit is not particularly limited, but usually it is often 15 GPa or less and more often 10 GPa or less.
The measuring method of the tensile elastic modulus _Eresin follows JIS-C-2151 (2006).

The average thickness of the resin layer 6 is not particularly limited, but is preferably 100 μm or less. If the average thickness of the resin layer 6 is 100 μm or less, the flexibility of the composite 2 can be sufficiently secured. Moreover, if the average thickness of the resin layer 6 is 100 micrometers or less, the curvature by the thermal expansion coefficient difference of resin and glass can be suppressed. The average thickness of the resin layer 6 is preferably 90 μm or less, more preferably 75 μm or less. Further, the average thickness of the resin layer 6 is preferably 0.5 μm or more, more preferably 1 μm or more, and further preferably 10 μm or more, from the viewpoint that the effect of the present invention is more excellent.
In addition, the said average thickness is the value which measured the thickness of arbitrary 10 or more resin layers 6, and arithmetically averaged them.

The resin layer 6 may be formed of only resin, for example. In addition, the resin layer 6 should just be formed with the material containing resin, for example, may be formed with resin and a filler.
Examples of the filler include fibrous or non-fibrous fillers such as plate-like, scale-like, granular, indefinite shape, and crushed products. Specifically, for example, glass fiber, PAN-based or pitch-based carbon fiber. , Stainless steel fiber, metal fiber such as aluminum fiber and brass fiber, organic fiber such as aromatic polyamide fiber, gypsum fiber, ceramic fiber, asbestos fiber, zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock Wool, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride whisker, mica, talc, kaolin, silica, calcium carbonate, glass beads, glass flake, glass microballoon, clay, molybdenum disulfide, wollastonite, Titanium oxide, zinc oxide, poly Calcium phosphate, metal powders, metal flakes, metal ribbons, metal oxides, carbon powder, graphite, carbon flake, scaly carbon, and carbon nanotubes. Specific examples of metal species of metal powder, metal flakes, and metal ribbons include silver, nickel, copper, zinc, aluminum, stainless steel, iron, brass, chromium, and tin. The type of glass fiber or carbon fiber is not particularly limited as long as it is generally used for resin reinforcement, and can be selected and used from, for example, long fiber type, short fiber type chopped strand, milled fiber, and the like. Moreover, the resin layer 6 may be comprised with the woven fabric and nonwoven fabric which were impregnated with resin.

The resin of the resin layer 6 may be various and may be, for example, either a thermoplastic resin or a thermosetting resin.
As the thermosetting resin, for example, polyimide (PI), epoxy (EP), or the like is used. Examples of the thermoplastic resin include polyamide (PA), polyamideimide (PAI), polyetheretherketone (PEEK), polybenzimidazole (PBI), liquid crystal polymer (LCP), polyethylene terephthalate (PET), polyethylene naphthalate ( PEN), polyethersulfone (PES), cyclic polyolefin (COP), polycarbonate (PC), polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), acrylic (PMMA), urethane (PU), etc. Used.
In addition, the resin layer 6 may be formed with a photocurable resin, and may be a copolymer or a mixture. The manufacturing process of the electronic device by the roll-to-roll method may include a process accompanied by heat treatment, and the heat-resistant temperature (continuous usable temperature) of the resin is preferably 100 ° C. or higher. Examples of the resin having a heat resistant temperature of 100 ° C. or higher include polyimide (PI), epoxy (EP), polyamide (PA), polyamideimide (PAI), polyetheretherketone (PEEK), polybenzimidazole (PBI), and polyethylene terephthalate. (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), cyclic polyolefin (COP), polycarbonate (PC), polyvinyl chloride (PVC), acrylic (PMMA), urethane (PU) and the like. .
Especially, as the resin in the resin layer 6, polyimide and epoxy are preferable and polyimide is more preferable because the effect of the present invention is more excellent.

The structure of the polyimide is not particularly limited, but is preferably composed of a repeating unit having a residue (X) of a tetracarboxylic acid and a residue (A) of a diamine represented by the following formula (I). In addition, it is preferable that a polyimide contains the repeating unit represented by Formula (I) as a main component (95 mol% or more with respect to all the repeating units is preferable), and other repeating units (for example, below-mentioned) The repeating unit represented by formula (2-1) or (2-2)).
The tetracarboxylic acid residue (X) is a tetracarboxylic acid residue obtained by removing a carboxy group from a tetracarboxylic acid, and the diamine residue (A) is a diamine obtained by removing an amino group from a diamine. Intended for residues.

  In formula (I), X represents a tetracarboxylic acid residue obtained by removing a carboxy group from tetracarboxylic acids, and A represents a diamine residue obtained by removing an amino group from diamines.

In formula (I), X represents a tetracarboxylic acid residue obtained by removing a carboxy group from tetracarboxylic acids, and at least one selected from the group consisting of groups represented by the following formulas (X1) to (X4) It preferably consists of a group. Especially, the group which consists of group which 50 mol% or more (preferably 80-100 mol%) of the total number of X is represented by the following formula | equation (X1)-(X4) at the point which the effect of this invention is more excellent. More preferably, it comprises at least one group selected from: More preferably, substantially all (100 mol%) of the total number of X is composed of at least one group selected from the group consisting of groups represented by the following formulas (X1) to (X4).
A represents a diamine residue obtained by removing an amino group from diamines, and preferably comprises at least one group selected from the group consisting of groups represented by the following formulas (A1) to (A8). Especially, the point which 50 mol% or more (preferably 80-100 mol%) of the total number of A consists of group represented by the following formula | equation (A1)-(A8) at the point which the effect of this invention is more excellent. More preferably, it comprises at least one group selected from: More preferably, substantially all (100 mol%) of the total number of A is composed of at least one group selected from the group consisting of groups represented by the following formulas (A1) to (A8).

  In addition, 80-100 mol% of the total number of X consists of at least 1 type chosen from the group which consists of group represented by the following formula | equation (X1)-(X4) by the point which the effect of this invention is more excellent. In addition, it is preferable that 80 to 100 mol% of the total number of A is composed of at least one group selected from the group consisting of the groups represented by the following formulas (A1) to (A8). Thus, the total number (100 mol%) is composed of at least one group selected from the group consisting of groups represented by the following formulas (X1) to (X4), and substantially the total number of A (100 Mol%) is more preferably composed of at least one group selected from the group consisting of groups represented by the following formulas (A1) to (A8).

Among these, X is preferably a group represented by the formula (X1) and a group represented by the formula (X4), and more preferably a group represented by the formula (X1) in that the effect of the present invention is more excellent. preferable.
Further, as A, the group represented by the formula (A1) and the group represented by the formula (A6) are preferable, and the group represented by the formula (A1) is more preferable in that the effect of the present invention is more excellent. .

  As a polyimide comprising a suitable combination of groups represented by formulas (X1) to (X4) and groups represented by formulas (A1) to (A8), X is a group represented by formula (X1). Yes, polyimide 1 in which A is a group represented by formula (A1), and polyimide 2 in which X is a group represented by formula (X4) and A is a group represented by formula (A6) Preferably mentioned. In the case of polyimide 1, it is more excellent in heat resistance. In the case of polyimide 2, it is preferable in terms of colorless and transparent.

  The number of repeating units (n) represented by the above formula (I) in the polyimide is not particularly limited, but is preferably an integer of 2 or more, and 10 to 10000 is more excellent in the effect of the present invention. Preferably, 15 to 1000 is more preferable.

  The polyimide may contain at least one selected from the group consisting of groups exemplified below as the residue (X) of the tetracarboxylic acids within a range not impairing the heat resistance. Moreover, 2 or more types of groups illustrated below may be included.

  Moreover, the said polyimide may contain 1 or more types chosen from the group which consists of group illustrated below as a residue (A) of diamine within the range which does not impair heat resistance. Moreover, 2 or more types of groups illustrated below may be included.

The resin layer 6 may cover a portion where it is desired to suppress the cracking of the glass substrate 4, and may have a form covering at least a part of one main surface of the resin layer 6. The resin layer 6 preferably covers the entire one main surface of the glass substrate 4. The resin layer 6 may protrude from one main surface of the glass substrate 4.
The production method of the resin layer 6 is not particularly limited, and optimal conditions are appropriately selected according to the material to be used. However, a liquid resin composition is applied on the glass substrate 4 in that the effect of the present invention is more excellent. A method of forming the resin layer 6 by solidification is then mentioned.

In addition, although the manufacturing method at the time of manufacturing the resin layer (polyimide resin layer) containing the polyimide mentioned above is not restrict | limited, The form which uses the curable resin used as the polyimide resin represented by the said Formula (I) by thermosetting Is preferred.
Hereinafter, the suitable form of the manufacturing method of a polyimide resin layer is explained in full detail. The production method preferably includes the following steps (1) and (2).
Step (1): Step of obtaining a coating film by applying a curable resin to be a polyimide resin represented by the above formula (I) on the glass substrate 4 by heat curing Step (2): Heat treatment of the coating film The process of forming a polyimide resin layer is described below in detail.

(Process (1): Coating film forming process)
Step (1) is a step of applying a curable resin, which becomes a polyimide resin having a repeating unit represented by the above formula (I), by thermal curing on the glass substrate 4 to obtain a coating film.
The curable resin contains a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine, and at least a part of the tetracarboxylic dianhydride is represented by the following formulas (Y1) to (Y4). Comprising at least one tetracarboxylic dianhydride selected from the group consisting of the following compounds, wherein at least some of the diamines are selected from the group consisting of compounds represented by the following formulas (B1) to (B8): It is preferable to consist of at least one diamine.

  In addition, a polyamic acid is normally represented as a structural formula containing the repeating unit represented by Formula (2-1) and / or Formula (2-2) below. In formulas (2-1) and (2-2), the definitions of X and A are the same as the definitions of X and A in formula (I), respectively.

The reaction conditions of tetracarboxylic dianhydride and diamines are not particularly limited, and it is preferable to react at −30 to 70 ° C. (preferably −20 to 40 ° C.) from the viewpoint that polyamic acid can be efficiently synthesized.
Although the mixing ratio in particular of tetracarboxylic dianhydride and diamines is not restrict | limited, Preferably tetracarboxylic dianhydride is 0.66-1.5 mol with respect to 1 mol of diamines, More preferably, it is 0.8. The reaction may be 9 to 1.1 mol, more preferably 0.97 to 1.03 mol.
In the reaction of tetracarboxylic dianhydride and diamines, an organic solvent may be used as necessary. The type of organic solvent to be used is not particularly limited. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylformamide, N, N-diethylformamide N-methylcaprolactam, hexamethylphosphoramide, tetramethylene sulfone, dimethyl sulfoxide, m-cresol, phenol, p-chlorophenol, 2-chloro-4-hydroxytoluene, diglyme, triglyme, tetraglyme, Dioxane, γ-butyrolactone, dioxolane, cyclohexanone, cyclopentanone and the like can be used, and two or more kinds may be used in combination.

In the case of the said reaction, other tetracarboxylic dianhydrides other than the tetracarboxylic dianhydride selected from the group which consists of a compound represented by said formula (Y1)-(Y4) as needed are added. You may use together.
Moreover, in the case of the said reaction, you may use together other diamines other than the diamine selected from the group which consists of a compound represented by said formula (B1)-(B8) as needed. Good.

In addition to the polyamic acid obtained by reacting the tetracarboxylic dianhydride and diamine, the curable resin used in this step is a tetracarboxylic dianhydride or diamine capable of reacting with a polyamic acid. You may use what added the kind. In addition to polyamic acid, when tetracarboxylic dianhydride or diamines are added, two or more polyamic acid molecules having a repeating unit represented by formula (2-1) or formula (2-2) are converted to tetracarboxylic diacid. It can be coupled through anhydrides or diamines.
When the polyamic acid has an amino group at the terminal, tetracarboxylic dianhydride may be added, and added so that the carboxyl group is 0.9 to 1.1 mol with respect to 1 mol of the polyamic acid. It's okay. When the polyamic acid has a carboxyl group at the end, diamines may be added, and the amino group may be added in an amount of 0.9 to 1.1 mol with respect to 1 mol of the polyamic acid. In addition, when a polyamic acid has a carboxyl group at the terminal, the acid terminal may be obtained by opening the terminal acid anhydride group by adding water or any alcohol.
The tetracarboxylic dianhydride added later is more preferably a compound represented by the formulas (Y1) to (Y4). The diamines added later are preferably diamines having an aromatic ring, and more preferably compounds represented by formulas (B1) to (B8).
When tetracarboxylic dianhydrides or diamines are added later, the polymerization degree (n) of the polyamic acid having a repeating unit represented by the formula (2-1) or the formula (2-2) is 1 to 20. Is preferred. When the degree of polymerization (n) is within this range, the viscosity of the curable resin solution can be reduced even when the polyamic acid concentration in the curable resin solution is 30% by mass or more.

In this step, components other than the curable resin may be used.
For example, a solvent may be used. More specifically, the curable resin may be dissolved in a solvent and used as a curable resin solution (curable resin solution). As the solvent, an organic solvent is particularly preferable from the viewpoint of the solubility of the polyamic acid. As an organic solvent used, the organic solvent used in the case of the reaction mentioned above is mentioned.
In addition, when the organic solvent is contained in the curable resin solution, the content of the organic solvent is not particularly limited as long as the thickness of the coating film can be adjusted and the coating property can be improved. 5-95 mass% is preferable with respect to the total solution mass, and 10-90 mass% is more preferable.
Further, if necessary, a dehydrating agent or a dehydrating ring closure catalyst for promoting dehydration ring closure of the polyamic acid may be used together. For example, as the dehydrating agent, for example, acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used. Moreover, as a dehydration ring closure catalyst, tertiary amines, such as a pyridine, a collidine, a lutidine, a triethylamine, can be used, for example.

The method for applying the curable resin (or curable resin solution) on the surface of the glass substrate is not particularly limited, and a known method can be used. Examples thereof include spray coating, die coating, spin coating, dip coating, roll coating, bar coating, screen printing, and gravure coating.
The thickness of the coating film obtained by the above treatment is not particularly limited, and is appropriately adjusted so that the polyimide resin layer having the desired thickness described above can be obtained.

(Process (2): Heat treatment process)
Step (2) is a step of forming a polyimide resin layer by heat-treating the coating film. By carrying out this step, for example, a ring closing reaction of polyamic acid contained in the curable resin proceeds, and a desired resin layer is formed.
The method for the heat treatment is not particularly limited, and a known method (for example, a method in which a support substrate with a coating film is left standing in a heating oven and heated) is appropriately used.
The heating temperature is not particularly limited, but is preferably 300 to 500 ° C., the residual solvent ratio is lowered, the imidization ratio is further increased, and the effect of the present invention is more excellent, and 350 to 450 ° C. is more preferable. preferable. Since the ring closing reaction of polyamic acid proceeds mainly at the heating temperature, the temperature is hereinafter also referred to as imidization temperature. As will be described later, it is preferable to gradually raise the heating temperature to the imidization temperature from the viewpoint that the effect of the present invention is more excellent.
The heating time is not particularly limited, and an optimal time is appropriately selected depending on the structure of the curable resin to be used. However, the residual solvent ratio is lowered, the imidization ratio is further increased, and the effect of the present invention is further improved. In this regard, the temperature rising time from room temperature to the imidization temperature is preferably 30 to 180 minutes, more preferably 60 to 120 minutes. Moreover, when implementing the drying heat processing mentioned later, the temperature rising time from the temperature in the case of a drying heat processing to imidation temperature should just be the said range. In addition, the temperature increase rate at the time of temperature increase is not particularly limited, and it is preferable to increase the temperature at a substantially constant rate (a constant temperature increase rate). The heating start temperature (drying temperature when dry heat treatment is performed) and a predetermined value It is preferable that it is the value which remove | divided the difference with imidation temperature of this by the predetermined temperature rising time. Specifically, when the heating start temperature is 120 ° C., the imidization temperature is 350 ° C., and the heating time is 120 minutes, the heating rate is (350−120) /120≈1.9° C./minute. Is preferred.
The holding time at the imidization temperature is preferably 30 to 120 minutes.
The heating atmosphere is not particularly limited, and is performed, for example, in the air, under vacuum, or under an inert gas.
Note that the heat treatment may be performed stepwise at different temperatures.
In addition, you may implement the drying heat processing for removing the volatile component (solvent) in a coating film before the process at the said heating temperature as needed. The temperature condition of the drying heat treatment is not particularly limited, but the heat treatment at 40 to 200 ° C. is preferable in that the effect of the present invention is more excellent. Also, the drying time is not particularly limited, and is preferably 15 to 120 minutes, more preferably 30 to 60 minutes, in that the effect of the present invention is more excellent. Note that the drying heat treatment may be performed stepwise at different temperatures.
Therefore, as one suitable form of this process (2), after implementing the drying heat processing at the said temperature, the form which further implements the said heat processing at 350-450 degreeC is mentioned.

By passing through the said process (2), the polyimide resin layer containing a polyimide resin is formed.
Although the imidation ratio of a polyimide resin is not particularly limited, it is preferably 99.0% or more and more preferably 99.5% or more in terms of more excellent effects of the present invention.
The imidation rate is measured by measuring the curable resin heated at 350 ° C. for 2 hours in a nitrogen atmosphere as 100% imidation rate, and the peak intensity (invariant before and after the heat treatment in the IR spectrum of the curable resin) ( For example, it is determined by the intensity ratio of the peak intensity derived from the imide carbonyl group: about 1780 cm ^{−1 to} the peak derived from the benzene ring: about 1500 cm ⁻¹ ).

  In the above step (1), a curable resin to be a polyimide resin having a repeating unit represented by the above formula (I) was applied on a glass substrate by thermosetting to produce a coating film. For example, a coating film may be formed by applying a composition containing a polyimide resin represented by the above formula (I) and a solvent.

<Composite and electronic device>
The composite described above includes a glass substrate 4 and a resin layer 6.
The light transmittance of the composite is not particularly limited, but may be 90% or less or 80% or less when applied to top emission OLED applications that do not require light to be transmitted through the back substrate.

Next, the electronic device will be described.
Examples of the electronic device include an image display panel, a solar battery, a thin film secondary battery, an image sensor (CCD, CMOS, etc.), a pressure sensor, an acceleration sensor, and a biological sensor. Examples of the image display panel include a liquid crystal panel (LCD), a plasma display panel (PDP), an organic EL panel (OLED), and electronic paper. The electronic device includes the composite having the above structure and an element formed over the composite.

  FIG. 3 is a diagram showing an organic EL panel (OLED) according to an embodiment of the present invention. The organic EL panel 70 includes, for example, the composite body 2, the pixel electrode 72, the organic layer 74, the counter electrode 76, the sealing plate 78, and the like. The organic layer 74 includes at least a light emitting layer, and includes a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer as necessary. For example, the organic layer 74 includes a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer in this order from the anode side. The pixel electrode 72, the organic layer 74, the counter electrode 76, and the like constitute a top emission type organic EL element 71. The organic EL element may be a bottom emission type.

  FIG. 4 is a diagram illustrating a liquid crystal panel according to an embodiment of the present invention. The liquid crystal panel 80 includes a TFT substrate 82, a CF substrate 84, a liquid crystal layer 86, and the like. The TFT substrate 82 is formed by patterning a TFT element (thin film transistor element) 83 or the like on the composite 2 (for example, the glass substrate 4 constituting the composite 2). The CF substrate 84 is formed by patterning a color filter element 85 on another composite 2 (for example, the glass substrate 4 constituting the composite 2). The liquid crystal layer 86 is formed between the TFT substrate 82 and the CF substrate 84. The TFT substrate 82 and the CF substrate 84 correspond to the electronic device described in the claims.

  FIG. 5 is a diagram illustrating a solar cell according to an embodiment of the present invention. The solar cell 90 is composed of, for example, the composite 2, the transparent electrode 92, the silicon layer 94, the reflective electrode 96, the sealing plate 98, and the like. The silicon layer includes, for example, a p layer (p-type doped layer), an i layer (light absorption layer), an n layer (n-type doped layer), and the like from the anode side. The transparent electrode 92, the silicon layer 94, the reflective electrode 96, and the like constitute a silicon type solar cell element 91. The solar cell element may be a compound type, a dye sensitized type, a quantum dot type, or the like.

  FIG. 6 is a view showing a thin film secondary battery according to an embodiment of the present invention. The thin film secondary battery 100 includes, for example, the composite 2, the transparent electrode 102, the electrolyte layer 104, the current collecting layer 106, the sealing layer 108, and the sealing plate 109. The thin-film secondary battery element 101 is configured by the transparent electrode 102, the electrolyte layer 104, the current collecting layer 106, the sealing layer 108, and the like. The thin-film secondary battery element 101 of this embodiment is a lithium ion type, but may be a nickel hydrogen type, a polymer type, a ceramic electrolyte type, or the like.

  FIG. 7 is a diagram illustrating electronic paper according to an embodiment of the present invention. The electronic paper 110 includes, for example, the composite 2, the TFT layer 112, a layer 114 containing an electrical engineering medium (for example, microcapsule), a transparent electrode 116, and a front plate 118. The electronic paper element 111 is composed of the TFT layer 112, the layer 114 containing an electrical engineering medium, the transparent electrode 116, and the like. The electronic paper element may be any of a microcapsule type, an in-plane type, a twist ball type, a particle movement type, an electron jet type, and a polymer network type.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. Example 1 is an example and Examples 2 and 3 are comparative examples.
In the following examples, a glass substrate X (average thickness 100 μm, width direction thickness deviation 1 μm or less, non-alkali glass, thermal expansion coefficient 4 × 10 ⁻⁶ / ° C., tensile elastic modulus 77 GPa) was used as the glass substrate. Many micro cracks existed on the surface of the glass substrate X. The width W of the microcracks was about 10 to 100 nm, and the depth d was 10 μm or less.
The glass substrate X was produced by a float method. Specifically, molten glass was flowed on molten tin and formed into a strip shape. After the formed glass was gradually cooled, the gradually cooled glass was cut into a desired size. In the slow cooling step and the cutting step, the glass was supported by compressed air pressure so that the glass did not come into contact with solid objects. In the cutting process, a laser cutting method which is a non-contact cutting method was used.

<Production Example 1: Production of polyamic acid solution (P1)>
Paraphenylenediamine (10.8 g, 0.1 mol) was dissolved in 1-methyl-2-pyrrolidone (226.0 g) and stirred at room temperature. BPDA (3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride) (29.4 g, 0.1 mol) was added to this over 1 minute, and the mixture was stirred at room temperature for 2 hours. ) And / or a polyamic acid solution (P1) having a solid content concentration of 20% by mass containing a polyamic acid having a repeating unit represented by the formula (2-2) was obtained. When the viscosity of this solution was measured, it was 3000 centipoise at 20 ° C.
The viscosity is measured by measuring the rotational viscosity at 20 ° C. using a DVL-BII type digital viscometer (B type viscometer) manufactured by Tokimec Co., Ltd.
X in the repeating unit represented by the formula (2-1) and / or formula (2-2) contained in the polyamic acid is a group represented by the formula (X1), and A is a formula (A1). The group represented.

<Example 1>
First, after cleaning the glass substrate X with pure water, it was further cleaned by UV cleaning.
Next, a polyamic acid solution (P1) is applied onto the first main surface of the glass substrate X by a spin coater (rotation speed: 2000 rpm, 15 seconds), and a coating film containing polyamic acid is provided on the glass substrate X. (Coating amount 100 g / m ² ).
The polyamic acid is a resin obtained by reacting the compound represented by the formula (Y1) with the compound represented by the formula (B1).
Next, it is heated in the atmosphere at 60 ° C. for 30 minutes, then heated at 120 ° C. for 30 minutes, further heated to 350 ° C. over 2 hours, held at 350 ° C. for 1 hour, and the coating film is heated. A resin layer (average thickness: 25 μm) was formed. In the formed resin layer, a polyimide resin having a repeating unit represented by the following formula (X in formula (I) is a group represented by formula (X1), A is represented by formula (A1)). Consisting of a group). The imidation ratio was 99.7%.

<Example 2>
The glass composite was heated in the same manner as in Example 1 except that the coating was heated at 60 ° C. for 30 minutes, then heated at 120 ° C. for 30 minutes and then directly placed in an oven at 350 ° C. for 1 hour. Got.

<Example 3>
After the resin layer (polyimide film) was formed in the same manner as in Example 1, the polyimide film was once peeled off and overlapped with another glass substrate X, using “HAL-TEC” manufactured by Sankyo, and the indentation amount was set to 1 mm. Roll lamination was performed below.

<Measurement of various parameters>
(“D _f / d”)
The depth d of the microcracks was obtained by directly observing the fracture starting point with an optical microscope after performing a fracture test described later on the glass substrate X.
Further, in the measurement of the depth _{d f} enters the resin, first, the isopropyl alcohol solution on the surface of the glass substrate X 3- aminopropyltriethoxysilane (KBM903) were dissolved 0.1 mass% by a spin coating (2000 rpm) Applied. Next, after drying at 80 ° C. for 10 minutes, an aqueous solution containing fluorescein isothiocyanate (concentration: 0.01 (mmol / l)) and a water-soluble resin (polyvinyl alcohol) is spin-coated (rotation speed: 2000 rpm, 15 seconds). ) On the first main surface of the glass substrate X. After the coating treatment, the glass substrate X is rinsed three times with pure water, dried, and then subjected to a destructive test described later. Then, the destructive start point is observed using a fluorescent microscope (Olympus), and the penetration depth _df is determined. Observed. In addition, the density | concentration of the polyvinyl alcohol in the said aqueous solution was adjusted so that the viscosity of aqueous solution might be comparable as the viscosity of the said polyamic acid solution (P1).
Moreover, although the method of measuring the penetration depth _df with a fluorescence microscope is shown above, after carrying out a destructive test to be described later on the obtained composite, the fracture starting point was directly observed with an optical microscope. the value of the fluorescence comparable with the depth d _f enter obtained from the microscope was observed.
When measurement with a microscope is difficult, the theoretical value is also obtained from the fracture stress / stress intensity factor from the fundamental equation of fracture mechanics d = (K / 2σ) ² (“Destructive Science of Ceramics” P68). It was used. (Elongation at break TE of resin layer)
The breaking elongation TE of the resin layer (polyimide resin layer) was measured according to ASTM D882-12.
(Yield stress σ _{S of} resin layer and tensile elastic modulus E _resin )
The yield stress σ _S and the tensile elastic modulus E _resin of the resin layer (polyimide resin layer) were measured according to JIS-C-2151: 2006.
In addition, about the breaking elongation TE of the resin layer (polyimide resin layer), the yield stress σ _S of the resin layer, and the tensile elastic modulus E _resin of the resin layer, the resin layer is peeled off from the obtained composite and the above measurement is performed. Carried out. When the resin layer could not be peeled off, the glass substrate was melted with hydrofluoric acid to obtain a resin layer for measurement.

<Evaluation (destructive test)>
The average breaking strength of the glass substrate when the resin layers prepared in Examples 1 to 3 were present was measured by the bending test apparatus shown in FIG.
Below, with reference to FIG. 8, the measuring method of the average fracture strength of the glass substrate when a resin layer does not exist is demonstrated first.

FIG. 8 is a view showing a bending test apparatus for examining the average breaking strength of the glass substrate of the present invention. In FIG. 8, when the lower support plate is moved in the left direction in the drawing with respect to the upper support plate in the state indicated by the solid line, the state indicated by the alternate long and short dash line is obtained.
As shown in FIG. 8, the bending test apparatus 10 includes an upper support plate 14 as a first support plate and a lower support plate 16 as a second support plate, and the upper support plate 14 and the lower support plate 16. The test sheet 18 is bent between the two.
The test sheet 18 is produced by processing a glass substrate produced at the same time as the glass substrate whose average breaking strength is desired. A glass substrate produced at the same time (for example, a glass substrate of the same lot) can be regarded as having the same degree of scratches on the surface. The test sheet 18 may be cut out from the glass substrate itself for which the average breaking strength is desired.

The test sheet 18 is formed in a rectangular shape in a natural state with no external force. The length of the short side of the test sheet 18 is 100 mm, and the length of the long side of the test sheet 18 is 150 mm.
The upper support plate 14 supports the test sheet 18. The support surface 14a of the upper support plate 14 is a downward flat surface. One short side portion of the test sheet 18 is fixed to the support surface 14a of the upper support plate 14 with a tape or the like, for example.
The lower support plate 16 supports the test sheet 18 in the same manner as the upper support plate 14. The support surface 16a of the lower support board 16 is an upward flat surface. The other short side portion of the rectangular test sheet 18 is placed on the support surface 16a of the lower support plate 16 and fixed by a static frictional force. The support surface 16 a of the lower support plate 16 is provided with a stopper 17 that comes into contact with the other short side portion of the test sheet 18 in order to prevent displacement of the test sheet 18.
In this bending test apparatus 10, first, the operator adjusts the distance D between the support surface 14 a of the upper support plate 14 and the support surface 16 a of the lower support plate 16 that are parallel to each other, and A predetermined tensile stress is generated on the test sheet 18 that is bent between the side support board 16 and the side support board 16.

The tensile stress σ generated at the top end of the curved portion of the test sheet 18 (the right end of the test sheet 18 in FIG. 8) can be calculated based on the following equation (2).
σ = A × E × t / (D−t) (2)
In the above formula (2), A is a constant (1.198) specific to this test, E is the tensile elastic modulus of the test sheet 18, and t is the thickness of the test sheet 18. As is clear from the equation (2), the tensile stress σ increases as the distance D (D> 2 × t) decreases.

Next, the operator moves the position of the lower support plate 16 relative to the upper support plate 14 once in a predetermined direction while maintaining the distance D. The moving speed is 10 mm / second, the moving distance is 100 mm, and the moving direction is a direction perpendicular to the short side of the test sheet 18.
Then, the operator checks whether or not a crack is formed on the test sheet 18 that is curved between the upper support plate 14 and the lower support plate 16. Whether or not a crack is formed is confirmed by an AE sensor that detects the presence or absence of an AE (Acoustic Emission) wave generated when the crack is formed.
When the test sheet 18 is not cracked, the operator narrows the distance D between the support surface 14a of the upper support plate 14 and the support surface 16a of the lower support plate 16 that are parallel to each other. As a result, a higher tensile stress than before is generated in the test sheet 18 that is curved between the upper support plate 14 and the lower support plate 16.

Next, the operator moves the position of the lower support plate 16 with respect to the upper support plate 14 while maintaining the distance D, and applies the test sheet 18 to bend between the upper support plate 14 and the lower support plate 16. It is examined whether or not a crack is formed. The fracture strength of the test sheet 18 can be determined by narrowing the interval D stepwise and increasing the tensile stress σ applied to the test sheet 18 stepwise until cracks are formed in the test sheet 18. The tensile stress σ when the test sheet 18 is cracked is used as the fracture strength.
The average value of the breaking strengths of the five test sheets 18 is used as the average breaking strength of the five test sheets 18.

Next, a method for measuring the average breaking strength of a composite having a resin layer will be described. When the resin layer is present, similarly to the case where the resin layer is not present, the bending test is performed so that a tensile stress is generated on the main surface bonded to the resin layer of the glass substrate using the bending test apparatus shown in FIG. Done. The tensile stress σ generated at the top end of the curved portion of the main surface of the glass substrate can be calculated based on the following formula (3).
σ = A × E × t / (D′−t) (3)
In the above formula (3), A is a constant (1.198) specific to this test, E is the tensile elastic modulus of the glass substrate, t is the thickness of the glass substrate, and D ′ is “D ′ = D−2 × u”. It is a value calculated from the formula of u represents the thickness of the resin layer. Due to the presence of the resin layer, the distance between the upper end and the lower end of the glass substrate is shorter than the distance D by 2 × u. Note that the amount of displacement of the neutral plane of the glass substrate due to the presence of the resin layer is 5% or less of the thickness t of the glass substrate and has little influence on the calculation result of the tensile stress σ, and is ignored. The neutral surface is a surface in which neither a tensile stress nor a compressive stress is generated, and when there is no resin layer, it is a center plane in the plate thickness direction of the glass substrate. The displacement amount of the neutral plane can be calculated using a general formula of material mechanics. The tensile stress σ _b when the glass substrate is broken is used as the fracture strength.

  The improvement rate of the average breaking strength of the glass substrate by presence of a reinforcement layer (resin layer) was computed using the apparatus mentioned above. This improvement rate is a value when the average breaking strength of the glass substrate when no reinforcing layer is present is used as a reference (100%). As the standard average breaking strength in Examples 1 to 3, the average breaking strength (154 MPa) of the glass substrate X was used.

  Moreover, the flexibility of the composites prepared in Examples 1 to 3 was evaluated based on the rate of increase in flexural rigidity of the composites. Here, the “rate of increase in bending stiffness” means the rate of increase in the bending stiffness of the composite based on the bending stiffness of the glass substrate when no resin layer is present. The bending stiffness was calculated using a general formula of structural mechanics. The lower the rate of increase in flexural rigidity, the better the flexibility.

  The evaluation results are shown in Table 1.

As shown in Example 1 of Table 1, it was confirmed that the composite of the present invention exhibited a desired effect. Moreover, since the bending rigidity did not increase so much, the flexibility did not decrease.
On the other hand, in Examples 2 and 3 that do not satisfy the requirements of the present invention, the desired effect was not obtained.

  As mentioned above, although embodiment, such as a composite_body | complex, was described, this invention is not limited to the said embodiment. The present invention can be modified and improved within the scope of the gist of the claims.

  Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on a Japanese patent application filed on June 16, 2014 (Japanese Patent Application No. 2014-123308), the contents of which are incorporated herein by reference.

2 Composite 4 Glass substrate 6 Resin layer 8 Microcrack 8a Linear microcrack 8b Dot-shaped microcrack 10 Bending test device 14 Upper support plate 16 Lower support plate 17 Stopper 18 Test sheet 70 Organic EL panel (OLED)
71 Organic EL element 72 Pixel electrode 74 Organic layer 76 Counter electrode 78 Sealing plate 80 Liquid crystal panel 82 TFT substrate 83 TFT element 84 CF substrate 85 Color filter element 86 Liquid crystal layer 90 Solar cell 91 Solar cell element 92 Transparent electrode 94 Silicon layer 96 Reflective electrode 98 Sealing plate 100 Thin film secondary battery 101 Thin film secondary battery element 102 Transparent electrode 104 Electrolyte layer 106 Current collecting layer 108 Sealing layer 109 Sealing plate 110 Electronic paper 111 Electronic paper element 112 TFT layer 114 Electrical engineering medium Including layer 116 Transparent electrode 118 Front plate

Claims (5)

A composite comprising a glass substrate having microcracks on the surface, and a resin layer disposed on the glass substrate,
The resin of the resin layer enters at least part of the inside of the microcrack,
To the depth d of the microcracks, and the ratio of the resin enters the depth d _f of from the glass substrate surface (d f _{/ d),} a breaking elongation TE of the resin layer (%) of the resin layer The product (ratio (d _f / d) × breaking elongation TE × yield stress σ _S ) with the yield stress σ _S (MPa) is 400 MPa ·% or more, and the tensile elastic modulus E _{resin of the} resin layer is 1. A composite that is greater than or equal to 0 GPa.   The composite according to claim 1, wherein the average thickness of the glass substrate is 10 to 200 μm.   The composite according to claim 1 or 2, wherein an average thickness of the resin layer is 10 to 100 µm.   The composite according to any one of claims 1 to 3, wherein the resin layer contains polyimide.   The electronic device containing the composite_body | complex of any one of Claims 1-4, and the element formed on the glass substrate of the said composite_body | complex.

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