JP2022058298A - Glass laminate, display device, electronic apparatus and resin layer - Google Patents

Abstract

To provide a glass laminate having excellent bending resistance and impact resistance and also having improved safety, and a display device and an electronic apparatus including the same, and a resin layer used therefor.SOLUTION: A glass laminate 1 has a glass substrate 2, a first resin layer 3, and a second resin layer 4. The glass substrate 2 has a first face, a second face opposite the first face, and a third face different from the first face and the second face. The glass substrate 2 has a thickness of 100 μm or less. The first resin layer 3 lies on the first surface side and has transparency. The second resin layer 4 covers the third face.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a glass laminate, a display device and an electronic device using the glass laminate, and a resin layer used therein.

Conventionally, in the display device, a cover member made of glass or resin has been used for the purpose of protecting the display device. This cover member protects the display device from impacts and scratches, and is required to have strength, impact resistance, scratch resistance, and the like. The glass cover member has features such as high surface hardness and scratch resistance, and high transparency, and the resin cover member has features such as light weight and resistance to breakage. Further, in general, the thicker the cover member, the higher the function of protecting the display device from impact, and the material and thickness of the cover member are appropriately selected and used from the viewpoint of weight, cost, size of the display device, and the like.

In recent years, flexible displays such as foldable displays, rollable displays, and bendable displays have been actively developed, and among them, foldable displays, that is, foldable display devices have been developed.

In a display device that can be bent, since the cover member also needs to bend in accordance with the movement of the display device, a cover member that can be bent is applied. In the case of a resin cover member, a film of polyimide or polyamide-imide which has been made colorless and transparent by devising a chemical structure has been developed (see, for example, Patent Document 1). Further, in the case of a cover member made of glass, a cover member such as ultra-thin glass (UTG) that can be bent by thinning the glass is under study (for example, a patent). See Document 2). Among the glasses, the one with particularly high bending resistance is called chemically strengthened glass, and by incorporating the stress that expands on the glass surface, minute scratches generated on the glass surface are prevented from becoming large during bending. This makes the glass hard to break.

Since glass has a higher elastic modulus than resin, it has a higher ability to protect the display device than resin for the same thickness. Further, the glass has high optical transparency, and it becomes possible to manufacture a display device having better visibility. On the other hand, as the glass becomes thinner, it becomes more fragile and the impact resistance is dramatically deteriorated. If the glass of the cover member is broken by an external impact, not only the function of protecting the display device is deteriorated, but also the generated debris and sharp end faces may damage the fingertips of the user.

Therefore, it has been proposed to laminate a resin layer on a glass substrate. For example, Patent Document 3 discloses a front plate for a display device in which a shatterproof layer is formed on a glass substrate.

Japanese Unexamined Patent Publication No. 2019-137864 Japanese Unexamined Patent Publication No. 2018-188335 Japanese Unexamined Patent Publication No. 2016-70972

In a display device including a glass substrate and a glass laminate having a resin layer, by arranging the resin layer closer to the observer than the glass substrate, the resin layer suppresses the cracking of the glass due to impact and has impact resistance. It is possible to increase. However, as described in Examples and Comparative Examples described later, when the resin layer is laminated on the glass base material, the bending resistance tends to be worse than that of the glass base material alone. As described above, the bending resistance and the impact resistance of the glass laminate are considered to be contradictory characteristics. Therefore, there is a demand for a glass laminate that can achieve both bending resistance and impact resistance.

The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a glass laminate having good bending resistance and impact resistance and improved safety.

In order to solve the above problems, the inventors of the present disclosure have studied diligently, and by arranging the resin layer on the main surface side of the thin glass substrate and covering the side surface of the glass substrate with the resin layer, It has been found that both good bending resistance and impact resistance can be achieved. The present disclosure is based on such findings.

One embodiment of the present disclosure is a glass laminate having a glass base material, a first resin layer, and a second resin layer, and the glass base material has a first surface and the first surface. The glass substrate has a second surface on the opposite side and a third surface different from the first surface and the second surface, the thickness of the glass substrate is 100 μm or less, and the first resin layer is: A glass laminate that exists on the first surface side and has transparency, and the second resin layer covers the third surface, provides a glass laminate.

In the glass laminate in the present disclosure, the first resin layer and the second resin layer may contain the same material and may be integral with each other.

Further, in the glass laminate in the present disclosure, it is preferable that (Equation 1) is satisfied when the thickness of the first resin layer is T1 and the thickness of the second resin layer is T2.
(Equation 1) 0.01 ≤ T1 / T2 ≤ 5.0

Further, in the glass laminate in the present disclosure, the ratio of the thickness of the second resin layer in the thickness direction of the glass substrate to the thickness of the glass substrate is preferably 0.5 or more. ..

Further, in the glass laminate in the present disclosure, it is preferable that the first resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin. Further, the second resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin, or a cured product of a resin composition containing a polymerizable compound. It is preferable to contain it.

Further, the glass laminate in the present disclosure may have a primer layer between the glass base material and the first resin layer.

Further, the glass laminate in the present disclosure can have a functional layer on the surface side of the first resin layer opposite to the glass substrate. In this case, the second resin layer and the functional layer may contain the same material and may be integrated. Further, in this case, it is preferable that the functional layer is a hard coat layer and the hard coat layer contains a cured product of a resin composition containing a polymerizable compound.

Further, the glass laminate in the present disclosure may have a third resin layer on the surface side of the glass base material opposite to the first resin layer. In this case, it is preferable that the third resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin. Further, in this case, the second resin layer and the third resin layer may contain the same material and may be integrated.

Further, in the glass laminate in the present disclosure, it is preferable that the glass base material is chemically tempered glass.

Further, in the glass laminate in the present disclosure, it is preferable that the total light transmittance of the first resin layer is 82% or more and the haze is 1.0% or less.

Further, the glass laminate in the present disclosure preferably has a total light transmittance of 82% or more and a haze of 1.0% or less.

Another embodiment of the present disclosure provides a display device comprising a display panel and the glass laminate described above arranged on the observer side of the display panel.

Another embodiment of the present disclosure provides an electronic device comprising the display device described above.

Another embodiment of the present disclosure is a resin layer that is arranged on the main surface side of a glass substrate having a thickness of 100 μm or less and is used for covering the side surface of the glass substrate, and is transparent. To provide a resin layer having.

The resin layer in the present disclosure contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin, or contains a cured product of a resin composition containing a polymerizable compound. Is preferable.

Further, the resin layer in the present disclosure preferably has a total light transmittance of 82% or more and a haze of 1.0% or less.

In the present disclosure, it is possible to provide a glass laminate having good bending resistance and impact resistance and improved safety.

It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic perspective view which illustrates the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic sectional drawing illustrating the glass laminated body in this disclosure. It is a schematic diagram for demonstrating a dynamic bending test. It is a schematic diagram for demonstrating a static bending test. It is a schematic cross-sectional view which illustrates the display device in this disclosure.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings and the like. However, the present disclosure can be implemented in many different embodiments and is not construed as being limited to the description of the embodiments exemplified below. Further, in order to clarify the explanation, the drawings may schematically show the width, thickness, shape, etc. of each part as compared with the actual form, but this is just an example and the interpretation of the present disclosure is limited. It's not something to do. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures may be designated by the same reference numerals, and detailed description thereof may be omitted as appropriate.

In the present specification, in expressing the aspect of arranging another member on one member, when the term "above" or "below" is simply used, the member should be in contact with the member unless otherwise specified. Including the case where another member is arranged directly above or directly below, and the case where another member is arranged above or below one member via another member. Further, in the present specification, when expressing the mode of arranging another member on the surface of a certain member, when simply expressing "on the surface side" or "on the surface", unless otherwise specified, the certain member is used. It includes both the case where another member is arranged directly above or directly below the member so as to be in contact with the member, and the case where another member is arranged above or below one member via another member.

Hereinafter, the glass laminate, the display device, the electronic device, and the resin layer in the present disclosure will be described in detail.

A. Glass laminated body The glass laminated body in the present disclosure is a glass laminated body having a glass base material, a first resin layer, and a second resin layer, and the glass base material has a first surface and the first surface. It has a second surface opposite to the surface and a third surface different from the first surface and the second surface, and the thickness of the glass substrate is 100 μm or less, and the first resin The layer exists on the first surface side and has transparency, and the second resin layer covers the third surface.
In other words, the glass laminate in the present disclosure includes a glass substrate having a thickness of 100 μm or less, a first resin layer arranged on one main surface side of the glass substrate and having transparency, and the glass base. It has a second resin layer that covers the side surface of the material.
Hereinafter, "the first resin layer is present on the first surface side and has transparency" is "arranged on one main surface side of the glass substrate and has transparency". It may be expressed as "1 resin layer".

FIG. 1 is a schematic cross-sectional view showing an example of the glass laminate in the present disclosure. As shown in FIG. 1, the glass laminate 1 is arranged on the glass base material 2 having a predetermined thickness and the first surface (hereinafter, may be referred to as the main surface) 2P side of the glass base material 2. It has a transparent first resin layer 3 and a second resin layer 4 that covers a third surface (hereinafter, may be referred to as a side surface) 2S of the glass base material 2.

In FIG. 1, the first resin layer 3 and the second resin layer 4 are configured as a single layer, but the present invention is not limited to this, and the first resin layer 3 and the second resin layer 4 may be configured as separate layers.

In the glass laminate in the present disclosure, the glass base material has a thickness of a predetermined value or less and is thin, so that bending resistance can be enhanced. On the other hand, since the glass base material has a thickness of a predetermined value or less and is thin, there is a concern that it is easily broken and has low impact resistance. On the other hand, in the present disclosure, since the first resin layer is arranged on the main surface side of the glass base material, when an impact is applied to the glass laminate, the first resin layer absorbs the impact. Cracking of the glass substrate can be suppressed, and impact resistance can be improved.

Here, as described in Examples and Comparative Examples described later, if the first resin layer is arranged on the main surface side of the glass substrate, the impact resistance can be improved, but the bending resistance is higher than that of the glass substrate alone. The sex gets worse. On the other hand, in the present disclosure, since the side surface of the glass base material is covered with the second resin layer, it is possible to improve the impact resistance while maintaining good bending resistance. The reason for this is inferred as follows.

The glass substrate is prone to microcracks during processing, and is particularly prone to microcracks at the edges of the glass substrate when the glass substrate is cut. If there are microcracks in the glass substrate, cracks are likely to occur starting from these microcracks. Even when tempered glass is used as the glass substrate, when a large glass substrate made of tempered glass is cut and used, the cut surface of the glass substrate, that is, the side surface is formed on the surface of the tempered glass. Since there is no compressive stress layer to be formed, the strength is reduced on the side surface of the glass substrate.

On the other hand, in the present disclosure, the strength of the side surface of the glass base material can be increased by covering the side surface of the glass base material with the second resin layer. Further, when the second resin layer is directly arranged on the side surface of the glass base material, the microcracks on the side surface of the glass base material can be filled by the second resin layer, and the strength of the side surface of the glass base material can be filled. Can be enhanced. Therefore, when the glass laminate is bent, cracking from the side surface of the glass base material can be suppressed, and good bending resistance can be maintained. Further, the impact resistance at the end portion of the glass base material can be enhanced.

Therefore, in the present disclosure, it is possible to achieve both good bending resistance and impact resistance. Furthermore, even if the glass base material in the glass laminate is damaged, the risk of damaging the human body can be reduced, and the glass laminate can be made highly safe. Therefore, the glass laminate in the present disclosure can be bent and can be used in a wide variety of display devices, for example, as a member for a foldable display.

Hereinafter, each configuration of the glass laminate in the present disclosure will be described.

1. 1. First Resin Layer The first resin layer in the present disclosure is arranged on the first surface side of the glass substrate and has transparency. The first resin layer can also function as a shock absorbing layer having shock absorbing properties and a shatterproof layer that suppresses shattering of glass when the glass base material is broken. When the glass laminate in the present disclosure is arranged on the observer side of the display panel of the display device, the first resin layer is arranged on the observer side rather than the glass substrate.

(1) Characteristics of the first resin layer The first resin layer has transparency. Specifically, the total light transmittance of the first resin layer is preferably 82% or more, more preferably 85% or more, and further preferably 88% or more. The upper limit is 100%.

Here, the total light transmittance of the first resin layer can be measured according to JIS K7361-1, and can be measured by, for example, a haze meter HM150 manufactured by Murakami Color Technology Research Institute. Hereinafter, the same can be applied to the method for measuring the total light transmittance of other layers.

The haze of the first resin layer is, for example, preferably 1.0% or less, more preferably 0.8% or less, still more preferably 0.5% or less. The lower limit of haze is 0%.

Here, the haze of the first resin layer can be measured according to JIS K-7136, and can be measured by, for example, a haze meter HM150 manufactured by Murakami Color Technology Research Institute. Hereinafter, the same can be applied to the method for measuring the haze of other layers.

The first resin layer preferably has shock absorption. Specifically, the composite elastic modulus of the first resin layer is preferably 4.7 GPa or more, and more preferably 5.7 GPa or more. When the composite elastic modulus of the first resin layer is within the above range, cracking of the glass substrate due to impact can be suppressed, and impact resistance and scratch resistance can be improved.

Further, according to the method for measuring the composite elastic modulus described later, since the composite elastic modulus of the glass substrate is about 40 GPa, the composite elastic modulus of the first resin layer is preferably, for example, 40 GPa or less, preferably 20 GPa. The following is more preferable.
Specifically, it is preferably 4.7 GPa or more and 40 GPa or less, and more preferably 5.7 GPa or more and 20 GPa or less.

Here, the composite elastic modulus of the first resin layer shall be calculated using the contact projection area _Ap obtained when measuring the indentation hardness ( _HIT ) of the first resin layer. The "indentation hardness" is a value obtained from the load-displacement curve from the load to the unloading of the indenter obtained by the hardness measurement by the nanoindentation method. The composite elastic modulus of the first resin layer is the elastic modulus including the elastic deformation of the first resin layer and the elastic deformation of the indenter.

The measurement of indentation hardness (HIT) shall be performed using "TI950 _{TriboIndenter} " manufactured by BRUKER Co., Ltd. for the measurement sample. Specifically, first, a block in which a glass laminate cut out to 1 mm × 10 mm is embedded with an embedding resin is prepared, and a uniform thickness of 50 nm or more without holes or the like is produced from this block by a general section preparation method. Cut out a section of 100 nm or less. "Ultra Microtome EM UC7" (manufactured by Leica Microsystems, Inc.) or the like can be used for preparing the sections. Then, the remaining block from which a uniform section having no holes or the like is cut out is used as a measurement sample. Next, in the cross section obtained by cutting out the section in such a measurement sample, a Berkovich indenter (triangular pyramid, TI-0039 manufactured by BRUKER) was first used as the indenter under the following measurement conditions. It is vertically pushed into the center of the cross section of the resin layer to a maximum pushing load of 25 μN over 10 seconds. Here, the Berkovich indenter is placed from the interface between the glass substrate and the first resin layer to the center side of the first resin layer in order to avoid the influence of the glass substrate and the influence of the side edge of the first resin layer. It shall be pushed into the portion of the first resin layer 500 nm away from both ends of the first resin layer to the center side of the resin layer, respectively. When an arbitrary layer such as a functional layer is present on the surface of the first resin layer opposite to the surface on the glass substrate side, the first is also from the interface between the arbitrary layer and the first resin layer. It shall be pushed into the portion of the first resin layer 500 nm away from the center side of the resin layer. After that, after holding it constant and relaxing the residual stress, it is unloaded over 10 seconds, the maximum load after relaxation is measured, and the maximum load _{P max} (μN) and the contact projected area Ap (nm ² ) are measured. ) And _{P max} / Ap to calculate the indentation hardness ( _HIT ). The contact projection area is a contact projection area in which the curvature of the indenter tip is corrected by the Oliver-Charr method using fused silica (5-00098 manufactured by BRUKER Co., Ltd.) as a standard sample. The indentation hardness ( _HIT ) shall be the arithmetic mean value of the values obtained by measuring at 10 points. If any of the measured values deviates by ± 20% or more from the arithmetic mean value, the measured value shall be excluded and remeasurement shall be performed. Whether or not any of the measured values deviates by ± 20% or more from the arithmetic mean value is determined by (AB) / B × 100 when the measured value is A and the arithmetic mean value is B. Judgment shall be made based on whether the required value (%) is ± 20% or more. The indentation hardness ( _HIT ) can be adjusted by the type of resin contained in the first resin layer, which will be described later.

(Measurement condition)
・ Load speed: 2.5 μN / sec ・ Holding time: 5 seconds ・ Load unloading speed: 2.5 μN / sec ・ Measurement temperature: 25 ° C

The composite elastic modulus _Er of the first resin layer is obtained by the following mathematical formula (1) using the contact projection area _Ap obtained when measuring the indentation hardness. For the composite elastic modulus, the indentation hardness is measured at 10 points, the composite elastic modulus is obtained each time, and the obtained composite elastic modulus is used as the arithmetic mean value of the obtained 10 points.

(In the above formula (1), _Ap is the contact projected area, _Er is the composite elastic modulus of the first resin layer, and S is the contact rigidity.)

(2) Thickness of the first resin layer The thickness of the first resin layer is not particularly limited as long as it can obtain flexibility and shock absorption, and is, for example, 5 μm or more and 60 μm or less. It is preferably 10 μm or more and 50 μm or less, and more preferably 15 μm or more and 40 μm or less. By making the thickness of the first resin layer relatively thin so as to be within the above range, flexibility can be enhanced, and cracking of the first resin layer can be suppressed when the glass laminate is bent. , Flexibility can be maintained.

Here, the thickness of the first resin layer is determined from the cross section in the thickness direction of the glass laminate observed by a transmission electron microscope (TEM), a scanning electron microscope (SEM), or a scanning transmission electron microscope (STEM). It can be an average value of the thicknesses of any 10 points obtained by measurement. Unless otherwise specified, the same method can be used for measuring the thickness of other layers of the glass laminate.

(3) Material of the first resin layer (a) Resin The resin contained in the first resin layer is not particularly limited as long as it is a resin satisfying the above-mentioned composite elastic coefficient and having transparency, for example. Examples thereof include polyurethane, polyester, polyimide resin, epoxy resin, and acrylic resin. These resins may be used alone or in combination of two or more.

In the present specification, the polyimide resin means a polymer having an imide bond in the main chain. Examples of the polyimide-based resin include polyimide, polyamide-imide, polyesterimide, and polyetherimide.

Hereinafter, polyimide will be described as an example.

(Polyimide)
Polyimide is obtained by reacting a tetracarboxylic acid component with a diamine component. It is preferable to obtain polyamic acid by polymerization of a tetracarboxylic acid component and a diamine component and imidize it. The imidization may be carried out by chemical imidization, thermal imidization, or a combination of chemical imidization and thermal imidization.

The polyimide is not particularly limited as long as it satisfies the above-mentioned composite elastic modulus and has transparency, and for example, the structural unit represented by the following general formula (1) is 10 mol% or more and 100 mol% or less, and The structural unit represented by the following general formula (2) is contained in (100-x) mol% (where x is the molar% of the structural unit represented by the above general formula (1)), and the weight average molecular weight is 100. It is preferably 000 or more. The polyimide has a tetracarboxylic acid residue having a specific structure containing a parabiphenylene group having a dihedral angle twisted in the main chain via an ester bond, and a diamine residue having an aromatic ring or an aliphatic ring. Moreover, by having a specific weight average molecular weight, it is easy to improve the balance between the composite elastic coefficient and the bending resistance.

(In the general formulas (1) and (2), R ¹ to R ⁴ independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and at least one of R ¹ and R ² and R ³ are represented. And at least one of ^R4 represents an alkyl group having 1 to 6 carbon atoms; A represents a tetravalent group which is a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring, and B represents an aromatic ring. Represents a divalent group that is a diamine residue having a family ring or an aliphatic ring.)

Here, the tetracarboxylic acid residue means a residue obtained by removing four carboxyl groups from the tetracarboxylic acid, and represents the same structure as the residue obtained by removing the acid dianhydride structure from the tetracarboxylic acid dianhydride. .. Further, the diamine residue means a residue obtained by removing two amino groups from diamine.

In the general formula (1), at least one of R ¹ and R ² and at least one of R ³ and R ⁴ represent an alkyl group having 1 to 6 carbon atoms. The alkyl group having 1 to 6 carbon atoms may be a linear or branched alkyl group, for example, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, or i-. Examples thereof include a butyl group, a t-butyl group, an n-pentyl group, and an n-hexyl group. From the viewpoint of solvent solubility, it is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 2 carbon atoms, and more preferably a methyl group. Further, among them, from the viewpoint of solvent solubility, it is preferable that R ¹ and R ² and R ³ and R ⁴ represent a methyl group.

In the general formula (1), B represents a divalent group which is a diamine residue having an aromatic ring or an aliphatic ring. The diamine residue having an aromatic ring or an aliphatic ring can be a residue obtained by removing two amino groups from a diamine having an aromatic ring or a diamine having an aliphatic ring.

Specific examples of the diamine having an aromatic ring and the diamine having an aliphatic ring include those described in JP-A-2019-132930 and JP-A-2019-1989. These can be used alone or in combination of two or more.

In the above general formula (2), A represents a tetravalent group which is a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring, and B is a diamine residue having an aromatic ring or an aliphatic ring. Represents a divalent group. Since B in the general formula (2) may be the same as B in the general formula (1), the description thereof is omitted here. B in the general formula (1) and B in the general formula (2) may be the same or different from each other.

The tetracarboxylic acid residue in A of the general formula (2) is a residue obtained by removing the acid dianhydride structure from the tetracarboxylic acid dianhydride having an aromatic ring, or a tetracarboxylic acid dianhydride having an aliphatic ring. It can be a residue obtained by removing the acid dianhydride structure from the anhydride.

Specific examples of the tetracarboxylic dianhydride having an aromatic ring and the tetracarboxylic dianhydride having an aliphatic ring are described in, for example, JP-A-2019-132930 and JP-A-2019-1989. Can be mentioned. These can be used alone or in combination of two or more.

The polyimide preferably contains 10 mol% or more and 100 mol% or less of the structural unit represented by the general formula (1). From the viewpoint of solubility in a solvent, the polyimide more preferably contains 15 mol% or more, more preferably 25 mol% or more, and 50 mol% or more of the structural unit represented by the above general formula (1). Is particularly preferred.

On the other hand, from the viewpoint of improving the surface hardness and transparency, the polyimide may contain a copolymerization component, and the polyimide may contain 95 mol% or less of the structural unit represented by the general formula (1), 90 mol% or less. The following may be contained, and 80 mol% or less may be contained.

Further, the polyimide may contain (100-x) mol% of the structural unit represented by the general formula (2) (where x is the molar% of the structural unit represented by the general formula (1)). preferable. From the viewpoint of solubility in a solvent, the polyimide contains 85 mol% or less, more preferably 75 mol% or less, and 50 mol% or less of the structural unit represented by the above general formula (2). Is particularly preferred.

When the polyimide contains 100 mol% of the structural unit represented by the general formula (1), the structural unit represented by the general formula (2) is 0 mol%, that is, not contained. The structural unit represented by the above general formula (2) may be 0 mol%, but may be contained as a copolymerization component from the viewpoint of improving surface hardness and transparency, and polyimide is the above general. The structural unit represented by the formula (2) may be contained in an amount of 5 mol% or more, 10 mol% or more, or 20 mol% or more.

From the viewpoint of improving transparency and surface hardness, at least one of the tetravalent group which is a tetracarboxylic acid residue of A and the divalent group which is a diamine residue of B is aromatic. A group comprising a group ring and in which (i) a fluorine atom, (ii) an aliphatic ring, and (iii) an aromatic ring are linked to each other with a sulfonyl group or an alkylene group which may be substituted with fluorine. It is preferable to include at least one selected from. When the polyimide contains at least one selected from a tetracarboxylic acid residue having an aromatic ring and a diamine residue having an aromatic ring, the molecular skeleton becomes rigid, the orientation is enhanced, and the surface hardness is improved, but the polyimide is rigid. The aromatic ring skeleton tends to have an absorption wavelength extending to a long wavelength, and the transmittance in the visible light region tends to decrease. On the other hand, when the polyimide contains (i) a fluorine atom, the transparency is improved in that the electronic state in the polyimide skeleton can be made difficult to transfer charge. Further, when the polyimide contains (ii) an aliphatic ring, transparency is improved in that the transfer of charges in the skeleton can be inhibited by breaking the conjugation of π electrons in the polyimide skeleton. Further, when the polyimide contains a structure in which (iii) aromatic rings are linked to each other with a sulfonyl group or an alkylene group which may be substituted with fluorine, the π electron in the polyimide skeleton is cut off from the conjugation of the charge in the skeleton. Transparency is improved in that it can inhibit movement.

Among them, at least one of the tetravalent group which is the tetracarboxylic acid residue of A and the divalent group which is the diamine residue of B is from the viewpoint of improving the transparency and the surface hardness. , The aromatic ring and the fluorine atom are preferably contained, and the divalent group which is the diamine residue of B preferably contains the aromatic ring and the fluorine atom.

In the polyimide, the diamine residue having the aromatic ring or the aliphatic ring in B in the general formulas (1) and (2) is trans. -Cyclohexanediamine residue, trans-1,4-bismethylenecyclohexanediamine residue, 4,4'-diaminodiphenylsulfone residue, 3,4'-diaminodiphenylsulfone residue, 2,2-bis (4-amino) Phenyl) propane residue, 3,3'-bis (trifluoromethyl) -4,4'-[(1,1,1,3,3,3-hexafluoropropane-2,2-diyl) bis (4) , 1-Phenyleneoxy)] dianiline residue, 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane residue, 2,2- From the group consisting of bis [4- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane residue and a divalent group represented by the following general formula (3). It is preferably a divalent group of at least one selected. In particular, from the viewpoint of achieving both transparency and surface hardness, 4,4'-diaminodiphenyl sulfone residue, 3,4'-diaminodiphenyl sulfone residue, 2,2-bis (4-aminophenyl) propane residue, And, it is preferable that it is at least one divalent group selected from the group consisting of the divalent group represented by the following general formula (3), and the divalent group represented by the following general formula (3). Is more preferable. As the divalent group represented by the following general formula ( ³ ), it is more preferable that R5 and R6 are perfluoroalkyl groups, and among them, a perfluoroalkyl group having ¹ or more and 3 or less carbon atoms is preferable. It is more preferably a trifluoromethyl group or a perfluoroethyl group. Further, as the alkyl group in R5 and R6 in the following general ^formula ( ³ ), an alkyl group having 1 or more carbon atoms and 3 or less carbon atoms is preferable, and a methyl group or an ethyl group is more preferable.

(In the general formula (3), R ⁵ and R ⁶ independently represent a hydrogen atom, an alkyl group, or a perfluoroalkyl group.)

In polyimide, the tetracarboxylic acid residue having an aromatic ring or an aliphatic ring in A in the above general formula (2) is cyclohexanetetracarboxylic, among others, from the viewpoint of transparency, bending resistance and surface hardness. Acid dianhydride residue, cyclopentanetetracarboxylic acid dianhydride residue, dicyclohexane-3,4,3', 4'-tetracarboxylic acid dianhydride residue, cyclobutanetetracarboxylic acid dianhydride residue, Pyromerutic acid dianhydride residue, 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride residue, 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride residue, 2 , 3,3', 4'-biphenyltetracarboxylic acid dianhydride residue, 4,4'-(hexafluoroisopropylidene) diphthalic acid anhydride residue, 3,4'-(hexafluoroisopropyridene) diphthalic acid Consists of anhydride residues, 3,3'-(hexafluoroisopropylidene) diphthalic acid anhydride residues, 4,4'-oxydiphthalic acid anhydride residues, and 3,4'-oxydiphthalic acid anhydride residues. It is preferably a tetravalent group of at least one selected from the group.

In A in the above general formula (2), it is preferable to contain 50 mol% or more, more preferably 70 mol% or more, and further preferably 90 mol% or more of these suitable residues in total.

As A in the above general formula (2), pyromellitic acid dianhydride residue, 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride residue, from the viewpoint of improving the surface hardness. And a group of tetracarboxylic acid residues suitable for improving rigidity, such as at least one selected from the group consisting of 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride residues. It is preferable to include A). Further, as A in the above general formula (2), cyclohexanetetracarboxylic acid dianhydride residue, cyclopentanetetracarboxylic acid dianhydride residue, dicyclohexane-3,4 are used from the viewpoint of improving transparency. , 3', 4'-tetracarboxylic acid dianhydride residue, cyclobutane tetracarboxylic acid dianhydride residue, 2,3,3', 4'-biphenyltetracarboxylic acid dianhydride residue, 4,4' -(Hexafluoroisopropylidene) diphthalic acid anhydride residue, 3,4'-(hexafluoroisopropyridene) diphthalic acid anhydride residue, 3,3'-(hexafluoroisopropyridene) diphthalic acid anhydride residue, Tetracarboxylic acid residue suitable for improving transparency, such as at least one selected from the group consisting of 4,4'-oxydiphthalic acid anhydride residues and 3,4'-oxydiphthalic acid anhydride residues. It is preferable to include a group (Group B). Group A and Group B may be mixed and used.

When group A and group B are mixed, a tetracarboxylic acid residue group (group A) suitable for improving the rigidity and a tetracarboxylic acid residue group (group B) suitable for improving transparency are used. ) To 1 mol of the tetracarboxylic acid residue group (group B) suitable for improving transparency, the tetracarboxylic acid residue group (group) suitable for improving the rigidity. A) is preferably 0.05 mol or more and 9 mol or less, more preferably 0.1 mol or more and 5 mol or less, and further preferably 0.3 mol or more and 4 mol or less.

Among them, from the viewpoint of improving surface hardness and transparency, the above group B includes 4,4'-(hexafluoroisopropyridene) diphthalic acid anhydride residue and 3,4'-(hexa) containing a fluorine atom. Fluoroisopropylidene) It is preferable to use at least one of diphthalic acid anhydride residues.

The content ratio of each repeating unit in the polyimide and the content ratio (mol%) of each tetracarboxylic acid residue and each diamine residue can be obtained from the molecular weight of the charged material at the time of producing the polyimide. Further, the content ratio (mol%) of each tetracarboxylic acid residue and each diamine residue in the polyimide is determined by high performance liquid chromatography, gas chromatograph mass spectrometer, and NMR for the decomposition product of the polyimide obtained in the same manner as described above. , Elemental analysis, XPS / ESCA and TOF-SIMS.

From the viewpoint of good bending resistance, the polyimide preferably has a weight average molecular weight of 100,000 or more in terms of polystyrene in gel permeation chromatography. From the viewpoint of bending resistance, the weight average molecular weight may be 120,000 or more, 140,000 or more, or 160,000 or more. On the other hand, the weight average molecular weight is preferably 270,000 or less because bubble defects are unlikely to occur. Further, from the viewpoint of solubility, the weight average molecular weight may be 250,000 or less, 230,000 or less, or 210,000 or less.

The weight average molecular weight of polyimide can be measured by gel permeation chromatography (GPC). Specifically, polyimide is used as an N-methylpyrrolidone (NMP) solution having a concentration of 0.1% by mass, and a 30 mmol% LiBr-NMP solution having a water content of 500 ppm or less is used as a developing solvent. 8120, column used: GPC LF-804 manufactured by SHODEX), measurement is performed under the conditions of a sample injection amount of 50 μL, a solvent flow rate of 0.4 mL / min, and 37 ° C. The weight average molecular weight is determined based on a polystyrene standard sample having the same concentration as the sample.

(B) Ultraviolet absorber The first resin layer may contain an ultraviolet absorber. Deterioration of the first resin layer due to ultraviolet rays can be suppressed. Above all, when the first resin layer contains polyimide, it is possible to suppress the color change of the first resin layer containing polyimide with time. Further, in a display device including a glass laminate, deterioration of members arranged on the display panel side of the glass laminate, such as a polarizing element, due to ultraviolet rays can be suppressed.

Examples of the ultraviolet absorber contained in the first resin layer include a triazine-based ultraviolet absorber, a benzophenone-based ultraviolet absorber such as a hydroxybenzophenone-based ultraviolet absorber, and a benzotriazole-based ultraviolet absorber.

Specific examples of benzophenone-based ultraviolet absorbers such as triazine-based ultraviolet absorbers and hydroxybenzophenone-based ultraviolet absorbers, and benzotriazole-based ultraviolet absorbers include those described in JP-A-2019-132930, for example. can.

As the ultraviolet absorber, a triazine-based ultraviolet absorber, a hydroxybenzophenone-based ultraviolet absorber, and a benzotriazole-based ultraviolet absorber are preferably used.

Further, the ultraviolet absorber is preferably a polymer or an oligomer. This is because it is possible to suppress the bleed-out of the ultraviolet absorber when the glass laminate is repeatedly bent. Examples of such an ultraviolet absorber include a polymer or oligomer having a triazine skeleton, a benzophenone skeleton, or a benzotriazole skeleton, and specifically, a (meth) acrylate having a benzotriazole skeleton or a benzotriazole skeleton. It is preferably obtained by thermally copolymerizing methyl methacrylate (MMA) at an arbitrary ratio.

The content of the ultraviolet absorber in the first resin layer is not particularly limited, but is preferably 1% by mass or more and 6% by mass or less, and more preferably 2% by mass or more and 5% by mass or less. If the content of the UV absorber is too small, the effect of the UV absorber may not be sufficiently obtained. Further, if the content of the ultraviolet absorber is too large, the first resin layer may be remarkably colored or the strength of the first resin layer may be lowered.

(C) Other Additives The first resin layer may further contain additives, if necessary. Examples of the additive include inorganic particles, a silica filler for facilitating winding, a surfactant for improving film forming property and defoaming property, and an adhesion improving agent.

(4) Method for Forming First Resin Layer As a method for forming the first resin layer, for example, a method of applying a resin composition on a glass substrate can be mentioned. The coating method is not particularly limited as long as it can be coated with a desired thickness. For example, a gravure coating method, a gravure reverse coating method, a gravure offset coating method, a spin coating method, a roll coating method, a reverse roll coating method, etc. Examples thereof include general coating methods such as a blade coating method, a dip coating method, a spray coating method, a die coating method, and a screen printing method. Further, as a method for forming the first resin layer, a transfer method of transferring the first resin layer to the main surface of the glass base material or a film-like first resin layer is attached to the main surface of the glass base material via an adhesive layer. A matching method can also be used.

The adhesive layer has transparency. Specifically, the total light transmittance of the adhesive layer is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more. The upper limit is 100%.

Examples of the adhesive used for the adhesive layer include a pressure-sensitive adhesive such as OCA (Optical Clear Adhesive) and a photosensitive adhesive.

The thickness of the adhesive layer is preferably 1 μm or more and 100 μm or less, for example. If the adhesive layer is too thick, the bending resistance may be impaired. On the other hand, if the thickness of the adhesive layer is too thin, the adhesiveness cannot be guaranteed and the adhesive layer may be peeled off.

Hereinafter, a case where the first resin layer contains polyimide will be described as an example.

(Method for forming the first resin layer containing polyimide)
As a method for forming the first resin layer containing polyimide, for example, a method of applying a polyimide varnish containing polyimide and an organic solvent on a glass substrate and drying it, and a method of forming a polyimide precursor (on the glass substrate). Examples thereof include a method of imidizing the polyimide precursor by heat treatment or chemical treatment after applying the polyimide precursor composition containing polyamic acid) and an organic solvent. In the former method, the heating conditions of the film forming process can be relaxed. On the other hand, in the latter method, since the solubility of the polyimide is not restricted, the choice of the chemical structure of the polyimide can be increased.

Among them, the following manufacturing method is mentioned as a preferable manufacturing method from the viewpoint that bubble defects are less likely to occur and it is easy to obtain a first resin layer having good thickness uniformity.

The method for forming the first resin layer containing polyimide is a polyimide varnish containing polyimide and an organic solvent, and the content ratio of the polyimide is 6% by mass or more and 15% by mass or less in the polyimide varnish. , A preparation step for preparing a polyimide varnish having a viscosity at 25 ° C. of 1,000 cps or more and 50,000 cps or less, a coating step of applying the polyimide varnish on a glass substrate, and drying the coating film at a temperature of 140 ° C. or less. It is preferable to have a first drying step of heating the coating film after drying at a temperature of 200 ° C. or higher.

When the polyimide is well dissolved in the organic solvent, the heating conditions of the film forming process can be relaxed. Therefore, it is preferable to form the first resin layer using a polyimide varnish in which the polyimide is dissolved in the organic solvent. When the polyimide has a specific amount or more of a structural unit containing a tetracarboxylic acid residue having a specific structure including a parabiphenylene group having a dihedral angle twisted in the main chain via an ester bond, it is easily dissolved in an organic solvent. .. When the polyimide has a solvent solubility such that it dissolves in an organic solvent at 25 ° C. in an amount of 6% by mass or more, the method for forming the first resin layer can be preferably used.

According to the method for forming the first resin layer, the polyimide content in the varnish can be increased to a sufficient concentration, and the varnish can be adjusted to a desired viscosity range, so that bubble defects are less likely to occur and the thickness is increased. A first resin layer having good uniformity can be obtained.

The organic solvent is not particularly limited as long as the polyimide can be dissolved, and for example, an aprotic polar solvent, a water-soluble alcohol solvent, or the like can be used. Among them, it contains nitrogen atoms such as N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphoramide, and 1,3-dimethyl-2-imidazolidinone. Organic solvent; it is preferable to use γ-butyrolactone or the like. Further, the organic solvent can be used as one kind or a mixed solvent of two or more kinds.

For the method of forming the first resin layer containing the polyimide, for example, the methods described in JP-A-2019-1989 and JP-A-2019-182974 can be referred to.

2. 2. Second Resin Layer The second resin layer in the present disclosure is a layer that covers the side surface of the glass substrate.

In addition, in this specification, the "side surface" of a glass base material means all the surfaces other than the 1st surface and the 2nd surface facing each other of the glass base material. Further, for example, when the glass base material is chamfered, the side surface of the glass base material may have a chamfered portion.

The second resin layer preferably has transparency. Specifically, the total light transmittance and haze of the second resin layer can be the same as the total light transmittance and haze of the first resin layer.

The second resin layer preferably has shock absorption. Specifically, the composite elastic modulus of the second resin layer can be the same as the composite elastic modulus of the first resin layer.

The method for measuring the composite elastic modulus of the second resin layer can be the same as the composite elastic modulus of the first resin layer.

The thickness of the second resin layer in the direction parallel to the main surface of the glass substrate is not particularly limited as long as it can obtain flexibility and shock absorption, and is, for example, 4 μm or more and 2000 μm or less. It is preferably 5 μm or more and 1000 μm or less, and more preferably 10 μm or more and 100 μm or less. When the thickness of the second resin layer in the direction parallel to the main surface of the glass base material is within the above range, cracking of the glass base material can be suppressed when the glass laminate is bent, and bending resistance can be suppressed. It is possible to improve the sex. Furthermore, the impact resistance at the end of the glass substrate can be improved.

The thickness of the second resin layer is 0.01 ≦ T1 / T2 ≦ 5.0 when the thickness of the first resin layer is T1 and the thickness of the second resin layer is T2. It is preferable to satisfy, more preferably 0.1 ≦ T1 / T2 ≦ 4.0, and particularly preferably 0.5 ≦ T1 / T2 ≦ 3.5.
When the thickness ratio is within the above range, cracking of the glass base material can be suppressed when the glass laminate is bent, and bending resistance can be improved. Furthermore, the impact resistance at the end of the glass substrate can be improved.

Here, the "thickness of the second resin layer" is the case where the most protruding portion on the third surface (side surface) of the glass substrate, that is, the laminate of the present disclosure is cut in the direction perpendicular to the third surface. In the cross section, it refers to the thickness in the direction opposite to the glass substrate itself and in the direction parallel to the first surface from the tip portion on the side surface of the glass substrate. When the thickness of the second resin layer from the tip portion on the side surface of the glass substrate is non-uniform, the thickness of the second resin layer from the tip portion on the side surface of the glass substrate is the smallest. The thickness.

The thickness of the second resin layer of the glass base material is appropriately determined according to the shape of the end portion of the glass base material and the like. For example, as shown in FIG. 2A, when the cross-sectional shape of the end portion of the glass base material 2 is trapezoidal, the thickness T2 of the second resin layer 4 is the tip portion 2E on the side surface of the glass base material 2. This is the smallest thickness among the thicknesses of the second resin layer 4 from the above.

Further, for example, as shown in FIG. 2B, when the cross-sectional shape of the end portion of the glass base material 2 is rectangular, the thickness T2 of the second resin layer 4 is the tip end on the side surface of the glass base material 2. This is the smallest thickness among the thicknesses of the second resin layer 4 from the portion 2E. Further, for example, as shown in FIG. 2C, when the cross-sectional shape of the end portion of the glass base material 2 is triangular, the thickness T2 of the second resin layer 4 is the tip on the side surface of the glass base material 2. The thickness of the second resin layer 4 from the portion 2E.

Further, for example, as shown in FIG. 2D, when the cross-sectional shape of the end portion of the glass base material 2 is a semi-elliptical shape, the thickness T2 of the second resin layer 4 is on the side surface of the glass base material 2. It is the thickness of the second resin layer 4 from the tip portion 2E. Further, for example, as shown in FIG. 3A, when the cross-sectional shape of the end portion of the glass base material 2 is substantially rectangular, the thickness T2 of the second resin layer 4 is on the side surface of the glass base material 2. This is the smallest thickness among the thicknesses of the second resin layer 4 from the tip portion 2E.

Furthermore, for example, as shown in FIG. 3B, when the cross-sectional shape of the end portion of the glass base material 2 is a thread chamfer shape, the thickness T2 of the second resin layer 4 is the side surface of the glass base material 2. It is the smallest thickness among the thicknesses of the second resin layer 4 from the tip portion 2E in the above. Further, for example, as shown in FIG. 3C, when the cross-sectional shape of the end portion of the glass base material 2 is a quadrant, the thickness T2 of the second resin layer 4 is the side surface of the glass base material 2. It is the thickness of the second resin layer 4 from the tip portion 2E in the above. Further, for example, as shown in FIG. 3D, when the cross-sectional shape of the end portion of the glass base material 2 is a semicircular shape, the thickness T2 of the second resin layer 4 is on the side surface of the glass base material 2. It is the thickness of the second resin layer 4 from the tip portion 2E.

The degree of coverage of the side surface of the glass substrate by the second resin layer is particularly high as long as it is possible to increase the strength of the side surface of the glass substrate by coating the side surface of the glass substrate with the second resin layer. Not limited. For example, the entire side surface of the glass substrate may be coated with the second resin layer, or a part of the side surface of the glass substrate may be coated with the second resin layer. More specifically, the entire side surface existing on the edge of the glass substrate may be coated with the second resin layer, and a part of the side surface existing on the edge of the glass substrate may be coated with the second resin layer. It may have been done. Further, the entire thickness direction of the glass substrate on the side surface may be entirely covered with the second resin layer, or a part of the glass substrate on the side surface in the thickness direction may be coated with the second resin layer. ..

The degree of coverage of the side surface of the glass base material by the second resin layer in the thickness direction of the glass base material is specifically, the second degree in the thickness direction of the glass base material with respect to the thickness T3 of the glass base material. The ratio of the thickness T4 of the resin layer (T4 / T3) is preferably, for example, 0.5 or more, and may be 1.0 or more, or may be 1.5 or more. When the above ratio (T4 / T3) is in the above range, cracking of the glass substrate can be suppressed when the glass laminate is bent, and bending resistance can be improved. Furthermore, the impact resistance at the end of the glass substrate can be improved. The upper limit of the above ratio (T4 / T3) is not particularly limited, and may be, for example, 3.0 or less. For example, in FIG. 4 (a), the above ratio (T4 / T3) is larger than 1, and in FIG. 4 (b), the above ratio (T4 / T3) is smaller than 1.

The thickness direction of the glass base material means a direction perpendicular to the main surface (first surface) of the glass base material. Further, the thickness of the second resin layer in the thickness direction of the glass base material is the surface (first surface) facing the main surface from the main surface (first surface) of the glass base material along the thickness direction of the glass base material. 2) The thickness of the second resin layer in the direction. For example, in FIGS. 2 (a) to 2 (d), FIGS. 3 (a) to (d), and FIGS. 4 (a) to 4 (c), the thickness T4 of the second resin layer in the thickness direction of the glass substrate. Is the thickness of the second resin layer 4 from the main surface 2P of the glass base material 2 along the thickness direction of the glass base material 2.

Here, the shape of the glass base material is usually a rectangular parallelepiped shape and a hexahedron. Further, for example, even when the glass base material is chamfered, the shape of the glass base material is usually rectangular parallelepiped and can be regarded as being substantially hexahedron. In this case, the glass substrate has a first surface and a second surface facing each other, and four third surfaces (side surfaces). In such a case, the degree of coating of the third surface of the glass substrate by the second resin layer is such that at least one third surface of the four third surfaces of the glass substrate is coated with the second resin layer. You just have to. That is, in this case, of the four third surfaces of the glass substrate, one third surface may be coated with the second resin layer, and the two third surfaces are coated with the second resin layer. Also, the three third surfaces may be coated with the second resin layer, or the four third surfaces may be coated with the second resin layer.

Above all, it is preferable that the two facing third surfaces of the four third surfaces of the glass substrate are covered with the second resin layer, and the glass laminate among the four third surfaces of the glass substrate is preferable. It is preferable that the two side surfaces substantially parallel to the bending direction of the glass are covered with the second resin layer. For example, as shown in FIGS. 5A and 5B, when the glass laminate 1 is bent, the glass base material is liable to crack at the bent portion 1F of the glass laminate 1. Therefore, if the two third surfaces of the four third surfaces of the glass substrate, which are substantially parallel to the bending direction D1 of the glass laminate 1, are covered with the second resin layer, the glass laminate is bent. It is possible to suppress the occurrence of cracks in the bent portion when the bent portion is made, and to improve the bending resistance.

In particular, it is preferable that all four third surfaces of the glass substrate are covered with the second resin layer. When the glass laminate is bent, cracking of the glass base material can be suppressed and bending resistance can be improved. Furthermore, the impact resistance at the end of the glass substrate can be improved.

Therefore, as described above, when the ratio (T1 / T2) of the thickness T1 of the first resin layer to the thickness T2 of the second resin layer is within a predetermined range, the glass substrate has a rectangular parallelepiped shape. In this case, it is preferable that the above ratio (T1 / T2) is within the above range on at least one third surface of the four third surfaces of the glass substrate. Above all, it is preferable that the above ratio (T1 / T2) is within the above range on the two opposing third surfaces among the four third surfaces of the glass substrate, and the four third surfaces of the glass substrate In all cases, it is more preferable that the above ratio (T1 / T2) is within the above range.

Further, as described above, when the ratio (T4 / T3) of the thickness T4 of the second resin layer in the thickness direction of the glass base material to the thickness T3 of the glass base material is within a predetermined range, the glass When the base material has a rectangular parallelepiped shape, it is preferable that the above ratio (T4 / T3) is within the above range on at least one third surface of the four third surfaces of the glass base material. Above all, it is preferable that the above ratio (T4 / T3) is within the above range on the two opposing third surfaces among the four third surfaces of the glass substrate, and the four third surfaces of the glass substrate In all cases, the above ratio (T4 / T3) is preferably within the above range.

Regarding the degree of coverage of the side surface of the glass substrate by the second resin layer, specifically, when the glass substrate is rectangular parallelepiped, the total length of the four sides when the glass substrate is viewed in a plan view. When is 100%, the ratio of the above ratio (T1 / T2) within the above range on the four sides of the glass substrate is preferably, for example, 2% or more, and is preferably 50% or more. More preferably, it is more preferably 90% or more. As described above, for example, as shown in FIGS. 5A and 5B, when the glass laminate 1 is bent, the glass base material is liable to crack at the bent portion 1F of the glass laminate 1. Therefore, if the above ratio (T1 / T2) is within the above range on the bent portion 1F on the two side surfaces substantially parallel to the bending direction D1 of the glass laminate 1 among the four side surfaces of the glass base material. , It is possible to suppress cracking of the glass base material when the glass laminate is bent. Therefore, even if the above ratio is 2%, improvement in bending resistance can be expected.

Further, regarding the degree of coverage of the side surface of the glass base material by the second resin layer, specifically, when the glass base material is rectangular parallelepiped, the total length of the four sides when the glass base material is viewed in a plan view. When is 100%, the ratio of the above ratio (T4 / T3) within the above range on the four sides of the glass substrate is preferably, for example, 2% or more, and is preferably 50% or more. More preferably, it is more preferably 90% or more. For the above reasons, even if the above ratio is 2%, improvement in bending resistance can be expected.

The thickness of the second resin layer in the direction parallel to the first surface and the thickness of the second resin layer in the thickness direction of the glass substrate are determined by a transmission electron microscope (TEM) and a scanning electron microscope (SEM). ) Or can be measured from a cross section in the thickness direction of the glass laminate observed by a scanning transmission electron microscope (STEM).

The second resin layer is not particularly limited as long as it covers the side surface of the glass base material, but is the same material as the other layers arranged on the main surface (first surface) side of the glass base material. It is preferable that the mixture contains and is integrated. When the second resin layer contains the same material as the other layer arranged on the main surface side of the glass substrate and is integrated, there is no interface between the second resin layer and the other layer. , The strength at the edge of the glass substrate can be increased. Further, since the second resin layer and other layers can be formed at the same time, the number of steps can be reduced and the manufacturing efficiency can be improved.

In the present disclosure, the two layers "contain the same material" or "contain the same material" mean that when the above two layers are analyzed by an analytical instrument, the error of the analytical instrument is taken into consideration. , Indicates that the same result will be obtained.

In addition, the fact that the second resin layer is integrated with the other layer means that the second resin layer and the other layer contain the same material and are continuously formed as one layer.

When the second resin layer contains the same material as the other layer and is integrated, the other layer may be a layer arranged on the main surface side of the glass substrate, for example, the first resin layer. Examples thereof include a functional layer described later and a third resin layer described later. For example, as shown in FIG. 1, the second resin layer 4 contains the same material as the first resin layer 3 and may be integrated. Further, for example, as shown in FIG. 6, when a functional layer such as a hard coat layer 5 is arranged on the surface side of the first resin layer 3 opposite to the glass base material 2, the second resin layer 4 is hard. It may contain the same material as the functional layer such as the coat layer 5 and may be integrated. Further, for example, as shown in FIG. 7, when the third resin layer 6 is arranged on the surface side of the glass base material 2 opposite to the first resin layer 3, the second resin layer 4 is the third resin layer. It may contain the same material as 6 and may be integrated.

As shown in FIG. 7, the first resin layer is formed when the first resin layer and the second resin layer are made of different materials and there is a boundary between the first resin layer and the second resin layer. , It exists up to the boundary with the second resin layer.

The material of the second resin layer can be the same as the material used for the first resin layer. Further, as the material of the second resin layer, the material used for the functional layer described later can also be used.

When the second resin layer is integrated with the first resin layer, the second resin layer contains the same material as the first resin layer. When the second resin layer is integrated with the third resin layer, the second resin layer contains the same material as the third resin layer. When the second resin layer is integrated with the functional layer, the second resin layer contains the same material as the functional layer.

The method for forming the second resin layer is appropriately selected depending on the form of the second resin layer and the like.

For example, when the second resin layer contains the same material as the first resin layer and is integrated, the second resin layer is formed at the same time as the formation of the first resin layer. Examples of the method for forming the first resin layer and the second resin layer include a method of applying the resin composition to the main surface and the side surface of the glass substrate. The coating method can be the same as the method for forming the first resin layer. When the second resin layer contains the same material as the first resin layer and is integrated, the first resin layer is formed on the main surface and the side surface of the glass base material as a method for forming the first resin layer and the second resin layer. It is also possible to use a transfer method for transferring the above-mentioned material or a method of adhering a film-shaped resin layer to the main surface and the side surface of the glass substrate via an adhesive layer. Further, when the second resin layer contains the same material as the third resin layer described later and is integrated, the above-mentioned second resin layer contains the same material as the first resin layer and is integrated. The same can be done. When the second resin layer contains the same material as the functional layer described later and is integrated, the second resin layer is formed at the same time as the functional layer is formed. The method for forming the functional layer and the second resin layer can be the same as the method for forming the functional layer described later.

3. 3. Glass base material The glass base material in the present disclosure has a thickness of 100 μm or less and is a member that supports the first resin layer.

The glass constituting the glass substrate is not particularly limited, but chemically strengthened glass is particularly preferable. Chemically tempered glass has excellent mechanical strength and is preferable in that it can be made thinner accordingly. Chemically strengthened glass is typically glass whose mechanical properties have been strengthened by a chemical method by partially exchanging ionic species such as replacing sodium with potassium near the surface of the glass. It has a compressive stress layer. In particular, chemically strengthened glass having a surface compressive stress value (CS) of 450 MPa or more is preferable.
Normally, the upper limit of the surface compressive stress value (CS) of chemically strengthened glass is 850 MPa or less.

Here, the surface compressive stress value (CS) of the chemically strengthened glass can be measured by, for example, a refractometer method. Specifically, it can be measured using a refractometer type glass surface stress meter FSM-6000LE manufactured by Luceo.

Examples of the glass constituting the chemically strengthened glass base material include aluminosilicate glass, soda lime glass, borosilicate glass, lead glass, alkaline barium glass, and aluminohousilicate glass.

Examples of commercially available chemically strengthened glass base materials include Corning's Gorilla Glass and AGC's Dragontrail. Further, as the chemically strengthened glass base material, for example, those described in JP-A-2019-194143 can also be used.

The thickness of the glass substrate is 100 μm or less, preferably 15 μm or more and 100 μm or less, more preferably 20 μm or more and 90 μm or less, and further preferably 25 μm or more and 80 μm or less. When the thickness of the glass substrate is as thin as the above range, good flexibility can be obtained and sufficient hardness can be obtained. In addition, curling of the glass laminate can be suppressed. Further, it is preferable in terms of weight reduction of the glass laminate.

The shape of the end portion of the glass substrate is not particularly limited. The cross-sectional shape of the end portion of the glass substrate is, for example, a trapezoidal shape as shown in FIG. 2 (a), a rectangular shape as shown in FIG. 2 (b), a triangular shape as shown in FIG. 2 (c), and the like. Semi-elliptical shape as shown in FIG. 2 (d), substantially rectangular shape as shown in FIG. 3 (a), thread chamfer shape as shown in FIG. 3 (b), quarter as shown in FIG. 3 (c). Any shape such as a circular shape or a semicircular shape as shown in FIG. 3D can be used.

Above all, the cross-sectional shape of the end portion of the glass base material is preferably a shape in which the corner portion of the end portion of the glass base material is chamfered. In the shape where the corners are chamfered, examples of the chamfering type include a corner surface, a round surface, an instep round surface, and a semi-cylindrical surface. Specifically, the shapes shown in FIGS. 2 (a), 2 (c), (d), and 3 (a) to 3 (d) can be mentioned. When the cross-sectional shape of the end portion of the glass substrate is a shape in which the corner portion is chamfered, the resin composition can be easily applied to the side surface of the glass substrate, and the second resin layer can be easily formed. Further, in this case, the bending resistance of the glass base material can be enhanced.

In particular, the cross-sectional shape of the end portion of the glass base material is preferably a shape in which the corner portion of the end portion of the glass base material has a rounded shape, that is, a shape in which the corner portion has an R shape. Examples of the shape in which the corner portion has an R shape include the shapes shown in FIGS. 2 (d), 3 (a), (c), and (d). When the cross-sectional shape of the end portion of the glass substrate has an R shape at the corner portion, the resin composition can be more easily applied to the side surface of the glass substrate, and the second resin layer can be easily formed. .. Further, in this case, the bending resistance of the glass base material can be further improved.

4. Functional layer The glass laminate in the present disclosure may further have a functional layer on the surface side of the first resin layer opposite to the glass substrate, that is, on the second surface side. Examples of the functional layer include a hard coat layer, a protective layer, an antireflection layer, an antiglare layer and the like.

Further, the functional layer may be a single layer or may have a plurality of layers. Further, the functional layer may be a layer having a single function, or may have a plurality of layers having different functions from each other. For example, the glass laminate in the present disclosure may have a hard coat layer and a protective layer as functional layers in order from the first resin layer side.

(1) Hard Court Layer As shown in FIG. 8, for example, the glass laminate in the present disclosure may further have a hard coat layer 5 on the surface side of the first resin layer 3 opposite to the glass base material 2. The hard coat layer is a member for increasing the surface hardness. By arranging the hard coat layer, scratch resistance can be improved.

(A) Characteristics of hard coat layer Here, the "hard coat layer" is a member for increasing the surface hardness, and specifically, in the configuration in which the glass laminate in the present disclosure has a hard coat layer, JIS When the pencil hardness test specified in K 5600-5-4 (1999) is performed, it means a hardness of "H" or higher.

When the glass laminate in the present disclosure has a hard coat layer on the surface side opposite to the glass substrate of the first resin layer, the pencil hardness of the surface of the glass laminate on the hard coat layer side is H or more. It is preferably 2H or more, more preferably 3H or more, and even more preferably 3H or more.

Here, the pencil hardness is measured by the pencil hardness test specified in JIS K5600-5-4 (1999). Specifically, using a test pencil specified by JIS-S-6006, a pencil hardness test specified by JIS K5600-5-4 (1999) was performed on the surface of the glass laminate on the hard coat layer side to scratch the surface. It can be done by evaluating the highest pencil hardness that does not have a mark. The measurement conditions can be an angle of 45 °, a load of 750 g, a speed of 0.5 mm / sec or more and 1 mm / sec or less, and a temperature of 23 ± 2 ° C. As the pencil hardness tester, for example, a pencil scratch coating film hardness tester manufactured by Toyo Seiki Co., Ltd. can be used.

(B) Structure of Hard Court Layer The hard coat layer may be a single layer or may have a multi-layer structure of two or more layers. When the hard coat layer has a multi-layer structure, in order to improve the surface hardness and to have a good balance between bending resistance and elastic modulus, the hard coat layer is dynamically combined with a layer for satisfying the pencil hardness. It is preferable to have a layer for satisfying the bending test (a layer for satisfying scratch resistance).

(C) Material of hard coat layer As the material of the hard coat layer, for example, an organic material, an inorganic material, an organic-inorganic composite material, or the like can be used.

Above all, the material of the hard coat layer is preferably an organic material. Specifically, the hard coat layer preferably contains a cured product of a resin composition containing a polymerizable compound. The cured product of the resin composition containing the polymerizable compound can be obtained by subjecting the polymerizable compound to a polymerization reaction by a known method using a polymerization initiator, if necessary.

(I) Polymerizable compound A polymerizable compound has at least one polymerizable functional group in the molecule. As the polymerizable compound, for example, at least one of a radically polymerizable compound and a cationically polymerizable compound can be used.

The radically polymerizable compound is a compound having a radically polymerizable group. The radically polymerizable group contained in the radically polymerizable compound may be any functional group capable of causing a radical polymerization reaction, and is not particularly limited, and examples thereof include a group containing a carbon-carbon unsaturated double bond. Examples thereof include a vinyl group and a (meth) acryloyl group. When the radically polymerizable compound has two or more radically polymerizable groups, these radically polymerizable groups may be the same or different from each other.

The number of radically polymerizable groups contained in one molecule of the radically polymerizable compound is preferably two or more, and more preferably three or more, from the viewpoint of improving the hardness of the hard coat layer.

As the radically polymerizable compound, a compound having a (meth) acryloyl group is preferable from the viewpoint of high reactivity, and for example, urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, and melamine ( Polyfunctional (meth) acrylate monomer having several (meth) acryloyl groups in a molecule called meth) acrylate, polyfluoroalkyl (meth) acrylate, silicone (meth) acrylate, etc. and having a molecular weight of hundreds to thousands. And oligomers can be preferably used, and polyfunctional (meth) acrylate polymers having two or more (meth) acryloyl groups in the side chains of the acrylate polymer can also be preferably used. Among them, a polyfunctional (meth) acrylate monomer having two or more (meth) acryloyl groups in one molecule can be preferably used. By including the cured product of the polyfunctional (meth) acrylate monomer in the hard coat layer, the hardness of the hard coat layer can be improved, and the adhesion can be further improved. Further, a polyfunctional (meth) acrylate oligomer or polymer having two or more (meth) acryloyl groups in one molecule can also be preferably used. By including the cured product of the polyfunctional (meth) acrylate oligomer or the polymer in the hard coat layer, the hardness and bending resistance of the hard coat layer can be improved, and the adhesion can be further improved.

In addition, in this specification, (meth) acryloyl represents each of acryloyl and methacryloyl, and (meth) acrylate represents each of acrylate and methacrylate.

Specific examples of the polyfunctional (meth) acrylate monomer include those described in JP-A-2019-132930. Among them, those having 3 or more and 6 or less (meth) acryloyl groups in one molecule are preferable from the viewpoint of high reactivity, improvement of the hardness of the hard coat layer, and adhesion, for example, pentaerythritol. Triacrylate (PETA), Dipentaerythritol Hexaacrylate (DPHA), Pentaerythritol Tetraacrylate (PETTA), Dipentaerythritol Pentaacrylate (DPPA), Trimethylol Propantri (meth) Acrylate, Trypentaerythritol Octa (Meta) Acrylate, Tetrapentaerythritol deca (meth) acrylates and the like can be preferably used, and in particular, pentaerythritol tri (meth) acrylates, dipentaerythritol penta (meth) acrylates, and dipentaerythritol hexaacrylates, which are PO, EO, or At least one selected from those modified with caprolactone is preferable.

The resin composition may contain a monofunctional (meth) acrylate monomer as a radically polymerizable compound in order to adjust hardness, viscosity, improve adhesion and the like. Specific examples of the monofunctional (meth) acrylate monomer include those described in JP-A-2019-132930.

The cationically polymerizable compound is a compound having a cationically polymerizable group. The cationically polymerizable group contained in the cationically polymerizable compound may be any functional group capable of causing a cationic polymerization reaction, and is not particularly limited, and examples thereof include an epoxy group, an oxetanyl group, and a vinyl ether group. When the cationically polymerizable compound has two or more cationically polymerizable groups, these cationically polymerizable groups may be the same or different from each other.

The number of cationically polymerizable groups contained in one molecule of the cationically polymerizable compound is preferably two or more, and more preferably three or more, from the viewpoint of improving the hardness of the hard coat layer.

Further, as the cationically polymerizable compound, a compound having at least one of an epoxy group and an oxetanyl group as a cationically polymerizable group is preferable, and a compound having at least one of an epoxy group and an oxetanyl group in one molecule is preferable. Is more preferable. A cyclic ether group such as an epoxy group or an oxetanyl group is preferable because the shrinkage associated with the polymerization reaction is small. Further, among the cyclic ether groups, compounds having an epoxy group are easily available, compounds having various structures are easily available, the durability of the obtained hard coat layer is not adversely affected, and compatibility with radically polymerizable compounds is easily controlled. There is an advantage. Further, among the cyclic ether groups, the oxetanyl group has a higher degree of polymerization than the epoxy group and has low toxicity, and when the obtained hard coat layer is combined with a compound having an epoxy group, it is contained in the coating film. There are advantages such as increasing the network formation rate obtained from the cationically polymerizable compound and forming an independent network without leaving an unreacted monomer in the film even in a region mixed with the radically polymerizable compound.

Examples of the cationically polymerizable compound having an epoxy group include polyglycidyl ether of a polyhydric alcohol having an alicyclic ring, or a cyclohexene ring or cyclopentene ring-containing compound with an appropriate oxidizing agent such as hydrogen peroxide or peracid. Alicyclic epoxy resin obtained by epoxidation; polyglycidyl ether of aliphatic polyhydric alcohol or its alkylene oxide adduct, polyglycidyl ester of aliphatic long chain polybasic acid, homopolymer of glycidyl (meth) acrylate, An aliphatic epoxy resin such as a copolymer; a glycidyl ether produced by reacting bisphenols such as bisphenol A, bisphenol F and hydrogenated bisphenol A, or derivatives such as alkylene oxide adducts and caprolactone adducts thereof with epichlorohydrin. And novolak epoxy resin and the like, and examples thereof include glycidyl ether type epoxy resin derived from bisphenols.

Specific examples of the alicyclic epoxy resin, the glycidyl ether type epoxy resin, and the cationically polymerizable compound having an oxetanyl group can be mentioned, for example, those described in JP-A-2018-104682.

The cured product of the resin composition containing the polymerizable compound contained in the hard coat layer includes a Fourier transform infrared spectrophotometer (FTIR), a thermal decomposition gas chromatograph device (GC-MS), and a decomposition product of the polymer. , High-speed liquid chromatography, gas chromatograph mass spectrometer, NMR, elemental analysis, XPS / ESCA, TOF-SIMS and the like can be used for analysis.

(Ii) Polymerization Initiator The resin composition may contain a polymerization initiator, if necessary. As the polymerization initiator, a radical polymerization initiator, a cationic polymerization initiator, a radical, a cationic polymerization initiator and the like can be appropriately selected and used. These polymerization initiators are decomposed by at least one of light irradiation and heating to generate radicals or cations to promote radical polymerization and cation polymerization. In some cases, the polymerization initiator is completely decomposed and does not remain in the hard coat layer.

Specific examples of the radical polymerization initiator and the cationic polymerization initiator include those described in JP-A-2018-104682.

(Iii) Particles The hard coat layer preferably contains inorganic or organic particles, and more preferably contains inorganic fine particles. The hardness can be improved by containing the particles in the hard coat layer.

Examples of the inorganic particles include metal oxides such as silica (SiO ₂ ), aluminum oxide, zirconia, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, and cerium oxide. Examples thereof include particles, metal fluoride particles such as magnesium fluoride and sodium fluoride, metal particles, metal sulfide particles, and metal nitride particles. Among them, metal oxide particles are preferable, at least one selected from silica particles and aluminum oxide particles is more preferable, and silica particles are even more preferable. This is because excellent hardness can be obtained.

Further, the inorganic particles have at least a reactive functional group having a photoreactivity capable of forming a covalent bond by cross-linking the inorganic particles with each other or with at least one of the polymerizable compounds on the surface of the inorganic particles. It is preferable that it is a reactive inorganic particle contained in a part of the above. The hardness of the hard coat layer can be further improved by performing a cross-linking reaction between the reactive inorganic particles or between the reactive inorganic particles and at least one of the radically polymerizable compound and the cationically polymerizable compound.

The reactive inorganic particles are coated with an organic component at least a part of the surface thereof, and have a reactive functional group introduced by the organic component on the surface. As the reactive functional group, for example, a polymerizable unsaturated group is preferably used, and more preferably a photocurable unsaturated group. Examples of the reactive functional group include an ethylenically unsaturated bond such as a (meth) acryloyl group, a vinyl group and an allyl group, and an epoxy group.

The reactive silica particles are not particularly limited, and conventionally known particles can be used. Examples thereof include the reactive silica particles described in JP-A-2008-165040. Examples of commercially available products of the reactive silica particles include those manufactured by Nissan Chemical Industries, Ltd .; MIBK-SD, MIBK-SDMS, MIBK-SDL, MIBK-SDZL, and JGC Catalysts and Chemicals Co., Ltd .; V8802, V8803 and the like.

Further, the silica particles may be spherical silica particles, but are preferably atypical silica particles. Spherical silica particles and atypical silica particles may be mixed. In the present specification, the atypical silica particles mean silica particles having a potato-like random unevenness on the surface. Since the surface area of the atypical silica particles is larger than that of the spherical silica particles, the inclusion of such atypical silica particles increases the contact area with the resin component and the like, and makes the hardness of the hard coat layer more excellent. Can be.

Whether or not the particles are atypical silica particles can be confirmed by observing the cross section of the hardcourt layer with an electron microscope.

The average particle size of the inorganic particles is preferably 5 nm or more, more preferably 10 nm or more, from the viewpoint of improving hardness. If the average particle size of the inorganic particles is too small, it is difficult to produce the particles, and the particles may easily aggregate with each other. Further, the average particle size of the inorganic particles is preferably 200 nm or less, more preferably 100 nm or less, and further preferably 50 nm or less from the viewpoint of transparency. If the average particle size of the inorganic particles is too large, large irregularities may be formed on the hard coat layer and haze may increase.

Here, the average particle size of the inorganic particles can be measured by observing the cross section of the hard coat layer with an electron microscope, and the average particle size of 10 arbitrarily selected particles is taken as the average particle size. The average particle size of the atypical silica particles is the average value of the maximum value (major axis) and the minimum value (minor axis) of the distance between two points on the outer periphery of the atypical silica particles that appeared by observing the cross section of the hard coat layer with a microscope. be.

The hardness of the hardcourt layer can be controlled by adjusting the size and content of the inorganic particles.
For example, the content of the silica particles is preferably 25 parts by mass or more and 60 parts by mass or less with respect to 100 parts by mass of the polymerizable compound.

(Iv) Ultraviolet absorber The hard coat layer may contain an ultraviolet absorber. Deterioration of the first resin layer due to ultraviolet rays can be suppressed. Above all, when the first resin layer contains polyimide, it is possible to suppress the color change of the first resin layer containing polyimide with time. Further, in a display device including a glass laminate, deterioration of members arranged on the display panel side of the glass laminate, such as a polarizing element, due to ultraviolet rays can be suppressed.

The ultraviolet absorber contained in the hard coat layer preferably has a peak absorption wavelength of 300 nm or more and 390 nm or less, more preferably 320 nm or more and 370 nm or less, and more preferably 330 nm or more and 370 nm or less. More preferred. Such an ultraviolet absorber can efficiently absorb ultraviolet rays in the UVA region, while inhibiting the curing of the hard coat layer by shifting the absorption wavelength of the initiator for curing the hard coat layer to 250 nm and the peak wavelength. This is because a hard coat layer having an ultraviolet absorbing ability can be formed without causing the above.

Among the ultraviolet absorbers, it is preferable that the peak of the absorption wavelength is 380 nm or less because coloring by the ultraviolet absorber can be suppressed.

The absorbance of the ultraviolet absorber can be measured using, for example, an ultraviolet-visible near-infrared spectrophotometer (for example, JASCO Corporation V-7100).

The ultraviolet absorber may be the same as the ultraviolet absorber used for the first resin layer.

Among them, one or more ultraviolet absorbers selected from the group consisting of hydroxybenzophenone-based ultraviolet absorbers and benzotriazole-based ultraviolet absorbers are preferable from the viewpoint of suppressing deterioration of the first resin layer by ultraviolet rays, and hydroxybenzophenone is preferable. More preferably, one or more UV absorbers selected from the group consisting of UV absorbers.

Specific examples of the hydroxybenzophenone-based ultraviolet absorber include those described in JP-A-2019-132930.

As the hydroxybenzophenone-based ultraviolet absorber, a 2-hydroxybenzophenone-based ultraviolet absorber is preferable, and one or more selected from the group consisting of benzophenone-based ultraviolet absorbers having the following general formula (A) is more preferable. preferable. It is possible to suppress deterioration of the first resin layer due to ultraviolet rays and improve durability.

(In the general formula (A), X ¹ and X ² independently represent a hydroxyl group, −OR ^a , or a hydrocarbon group having 1 to 15 carbon atoms, and Ra is ^a hydrocarbon having 1 to 15 carbon atoms. Represents a group.)

In the general formula ( ^A ), the hydrocarbon groups having 1 to 15 carbon atoms in X ¹ , X ² and Ra are methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group and octyl. Examples thereof include a group, a dodecyl group, an allyl group, a benzyl group and the like. Each of the aliphatic hydrocarbon groups having 3 or more carbon atoms may be linear or branched. The hydrocarbon group preferably has 1 to 12 carbon atoms, and more preferably 1 to 8 carbon atoms. The hydrocarbon group is preferably an aliphatic hydrocarbon group, and more preferably a methyl group or an allyl group, from the viewpoint of easily improving transparency.

From the viewpoint of easily improving durability, it is preferable that X ¹ and X ² are independently hydroxyl groups or −OR ^a .

Among the ones or more selected from the group consisting of benzophenone-based ultraviolet absorbers having the general formula (A), 2,2', 4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4, It is preferably at least one selected from the group consisting of 4'-dimethoxybenzophenone and 2,2'-dihydroxy-4,4'-diallyloxybenzophenone, preferably 2,2', 4,4'-tetrahydroxy. More preferably, it is at least one selected from the group consisting of benzophenone and 2,2'-dihydroxy-4,4'-dimethoxybenzophenone.

Specific examples of the benzotriazole-based ultraviolet absorber include those described in JP-A-2019-132930.

As the benzotriazole-based ultraviolet absorber, 2- (2-hydroxyphenyl) benzotriazoles are preferable, and one or more selected from the group consisting of benzotriazole-based ultraviolet absorbers having the following general formula (B). It is more preferable to have. It is possible to suppress deterioration of the first resin layer due to ultraviolet rays and improve durability.

(In the general formula (B), Y ¹ , Y ² and Y ³ independently represent a hydrogen atom, a hydroxyl group, −OR ^b , or a hydrocarbon group having 1 to 15 carbon atoms, and R ^b is a carbon atom. Represents a hydrocarbon group of number 1 to 15, where at least one of Y ¹ , Y ² and Y ³ represents a hydroxyl group, —OR ^b , or a hydrocarbon group having ¹ to 15 carbon atoms. Represents a hydrogen atom or a halogen atom.)

In the general formula (B), the hydrocarbon groups having 1 to 15 carbon atoms in Y ¹ , Y ² , Y ³ and R ^b are methyl group, ethyl group, propyl group, butyl group, pentyl group and hexyl group. , Heptyl group, octyl group, dodecyl group and the like. Each of the aliphatic hydrocarbon groups having 3 or more carbon atoms may be linear or branched. The hydrocarbon group preferably has 1 to 12 carbon atoms, and more preferably 1 to 8 carbon atoms. The hydrocarbon group is preferably an aliphatic hydrocarbon group, preferably a linear or branched alkyl group, and above all, a methyl group, a t-butyl group, or t-, from the viewpoint of easily improving transparency. It is preferably a pentyl group, an n-octyl group, or a t-octyl group.

^In the general formula (B), examples of the halogen atom in Y4 include a chlorine atom, a fluorine atom, a bromine atom and the like, and a chlorine atom is preferable.

In the general formula (B), it is preferable that Y ¹ and Y ³ are hydrogen atoms and Y ² is a hydroxyl group or −OR ^b , and 2- (2-hydroxy-4-octyloxyphenyl) -2H. More preferably, it is one or more selected from the group consisting of -benzotriazole and 2- (2,4-dihydroxyphenyl) -2H-benzotriazole. It is possible to suppress deterioration of the first resin layer due to ultraviolet rays and improve durability.

The content of the ultraviolet absorber in the hard coat layer is preferably, for example, 10% by mass or less, and more preferably 7% by mass or less, from the viewpoint of suppressing haze caused by mixing the ultraviolet absorber. preferable. Further, from the viewpoint of suppressing deterioration of the first resin layer due to ultraviolet rays and improving durability, the content of the ultraviolet absorber in the hard coat layer is preferably 1% by mass or more and 6% by mass or less. It is more preferably mass% or more and 5% by mass or less.

(V) Antifouling agent The hardcoat layer may contain an antifouling agent. Antifouling property can be imparted to the glass laminate.

The antifouling agent is not particularly limited, and examples thereof include a silicone-based antifouling agent, a fluorine-based antifouling agent, and a silicone-based and fluorine-based antifouling agent. Further, the antifouling agent may be an acrylic antifouling agent. As the antifouling agent, one type may be used alone, or two or more types may be mixed and used.

The hard coat layer containing a silicone-based antifouling agent or a fluorine-based antifouling agent is hard to get fingerprints (not noticeable) and has good wiping property. Further, when a silicone-based antifouling agent or a fluorine-based antifouling agent is contained, the surface tension at the time of applying the curable resin composition for the hard coat layer can be lowered, so that the leveling property is good and the obtained hard coat layer can be obtained. The appearance of is good.

Further, the hard coat layer containing a silicone-based antifouling agent has good slipperiness and scratch resistance. In a display device provided with a glass laminate having a hard coat layer containing such a silicone-based antifouling agent, the slipperiness when contacted with a finger, a pen, or the like is improved, so that the tactile sensation is improved.

The antifouling agent preferably has a reactive functional group in order to enhance the durability of the antifouling performance. When the antifouling agent does not have a reactive functional group, the glass laminate is hard when the glass laminate is laminated, regardless of whether the glass laminate is in the form of a roll or a sheet. When the antifouling agent is transferred to the surface opposite to the surface on the coat layer side and another layer is attached or applied to the surface opposite to the surface on the hard coat layer side of the glass laminate, the other Layer may be peeled off, and further, other layers may be easily peeled off when repeatedly bent. On the other hand, when the antifouling agent has a reactive functional group, the performance sustainability of the antifouling performance becomes good.

The number of reactive functional groups contained in the antifouling agent may be 1 or more, preferably 2 or more. By using an antifouling agent having two or more reactive functional groups, excellent scratch resistance can be imparted to the hardcoat layer.

Further, the antifouling agent preferably has a weight average molecular weight of 5000 or less. The weight average molecular weight of the antifouling agent can be measured by gel permeation chromatography (GPC).

The antifouling agent may be uniformly dispersed in the hardcoat layer, but from the viewpoint of obtaining sufficient antifouling property with a small amount of addition and suppressing a decrease in the strength of the hardcoat layer, the antifouling agent is placed on the surface side of the hardcoat layer. It is preferable that they are unevenly distributed.

As a method of unevenly distributing the antifouling agent on the surface side of the hard coat layer, for example, at the time of forming the hard coat layer, the coating film of the curable resin composition for the hard coat layer is dried and before being cured. By heating to reduce the viscosity of the resin component contained in the coating film to increase the fluidity, the antifouling agent is unevenly distributed on the surface side of the hard coat layer, or an antifouling agent with low surface tension is used. Examples thereof include a method in which the antifouling agent is floated on the surface of the coating film without applying heat when the coating film is dried, and then the coating film is cured so that the antifouling agent is unevenly distributed on the surface side of the hard coat layer.

The content of the antifouling agent is preferably 0.01 parts by mass or more and 3.0 parts by mass or less with respect to 100 parts by mass of the resin component. If the content of the antifouling agent is too small, it may not be possible to impart sufficient antifouling property to the hardcoat layer, and if the content of the antifouling agent is too large, the hardness of the hardcoat layer may decrease. be.

(Vi) Other Additives The hardcourt layer may further contain additives, if desired. The additive is appropriately selected depending on the function to be imparted to the hard coat layer, and is not particularly limited. For example, an inorganic or organic particle for adjusting the refractive index, an infrared absorber, an antiglare agent, or an antifouling agent. , Antistatic agents, colorants such as blue pigments and purple pigments, leveling agents, surfactants, lubricants, various sensitizers, flame retardant agents, adhesive additives, polymerization inhibitors, antioxidants, light stabilizers, Examples include surface modifiers.

(D) Thickness of hard coat layer The thickness of the hard coat layer may be appropriately selected depending on the material of the hard coat layer, the function of the hard coat layer, and the use of the glass laminate. For example, when the material of the hard coat layer is an organic material, the thickness of the hard coat layer is preferably 2 μm or more and 50 μm or less, more preferably 3 μm or more and 30 μm or less, and 5 μm or more and 20 μm or less. It is more preferably 6 μm or more and 10 μm or less. Further, for example, when the material of the hard coat layer is an inorganic material, the thickness of the hard coat layer can be about several tens of nm. When the thickness of the hard coat layer is within the above range, sufficient hardness can be obtained as the hard coat layer, and a glass laminate having good bending resistance can be obtained.

(E) Method for Forming Hard Court Layer The method for forming the hard coat layer is appropriate depending on the material of the hard coat layer and the like. For example, the hard coat layer containing the polymerizable compound and the like on the first resin layer. Examples thereof include a method of applying a curable resin composition for curing and curing, a vapor deposition method, a sputtering method and the like.

The curable resin composition for a hard coat layer contains a polymerizable compound, and may further contain a polymerization initiator, particles, an ultraviolet absorber, a solvent, an additive and the like, if necessary.

The method for applying the curable resin composition for a hard coat layer on the first resin layer is not particularly limited as long as it can be applied to a desired thickness, for example, a gravure coat method, a gravure reverse coat method, and the like. General coating methods such as a gravure offset coating method, a spin coating method, a roll coating method, a reverse roll coating method, a blade coating method, a dip coating method, a spray coating method, a die coating method, and a screen printing method can be mentioned. Further, a transfer method can also be used as a method for forming a coating film of the resin composition for a hard coat layer.

The coating film of the curable resin composition for the hard coat layer is dried as necessary to remove the solvent. Examples of the drying method include vacuum drying, heat drying, and a method of combining these drying methods. For example, it can be dried by heating at a temperature of 30 ° C. or higher and 120 ° C. or lower for 10 seconds or longer and 180 seconds or lower.

As a method for curing the coating film of the curable resin composition for the hard coat layer, it is appropriately selected depending on the polymerizable group of the polymerizable compound, and for example, at least one of light irradiation and heating can be used.

Ultraviolet rays, visible rays, electron beams, ionizing radiation and the like are mainly used for light irradiation. In the case of ultraviolet curing, for example, ultraviolet rays emitted from light rays such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, and a metal halide lamp can be used. The irradiation amount of the energy radiation source can be, for example, about 50 mJ / cm ² or more and 5000 mJ / cm ² or less as the integrated exposure amount at the ultraviolet wavelength of 365 nm.

When heating, for example, the treatment can be performed at a temperature of 40 ° C. or higher and 120 ° C. or lower. Further, the reaction may be carried out by leaving it at room temperature (25 ° C.) for 24 hours or more.

Further, as a method of forming the hard coat layer, a method of using a hard coat film in which the hard coat layer is arranged on one surface of the base material layer and laminating the hard coat film on the first resin layer via an adhesive layer. Can also be used. In this case, for example, as shown in FIG. 9, a hard coat film 15 having an adhesive layer 7, a base material layer 11 and a hard coat layer 5 on the surface side of the first resin layer 3 opposite to the glass base material 2. Can be arranged in this order.

The adhesive layer has transparency. Specifically, the total light transmittance of the adhesive layer is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more. The upper limit is 100%.

Examples of the adhesive used for the adhesive layer include a pressure-sensitive adhesive such as OCA (Optical Clear Adhesive) and a photosensitive adhesive.

The thickness of the adhesive layer is preferably 1 μm or more and 100 μm or less, for example. If the adhesive layer is too thick, the bending resistance may be impaired. On the other hand, if the thickness of the adhesive layer is too thin, the adhesiveness cannot be guaranteed and the adhesive layer may be peeled off.

(2) Protective Layer The glass laminate in the present disclosure may further have a protective layer on the surface side of the first resin layer opposite to the glass substrate.

The protective layer is transparent. Specifically, the total light transmittance of the protective layer is preferably 85% or more, more preferably 88% or more, and further preferably 90% or more. The upper limit is 100%.

The protective layer is not particularly limited as long as it has transparency, and may contain, for example, a resin. The resin used for the protective layer is not particularly limited as long as it is a resin capable of obtaining a transparent protective layer, and a general resin can be used.

As a method of arranging the protective layer on the main surface of the glass base material, for example, a method of using a protective film as the protective layer and bonding the first resin layer and the protective film via the adhesive layer, or a method of bonding the first resin layer and the protective film on the first resin layer. Examples thereof include a method of forming a protective layer.

The adhesive layer can be the same as the adhesive layer described in the above-mentioned hard coat layer section.

5. Other Structures The glass laminate in the present disclosure may have other layers, if necessary, in addition to the above-mentioned layers. Examples of the other layer include a primer layer, a third resin layer, a decorative layer, and the like.

(1) Primer layer The glass laminate in the present disclosure may have a primer layer 8 between the glass base material 2 and the first resin layer 3, as shown in FIGS. 9 to 11, for example. Further, as described later, when the glass laminate in the present disclosure has a third resin layer on the surface side opposite to the first resin layer of the glass base material, the glass base material and the third resin layer are used. A primer layer may be provided between them. The primer layer can improve the adhesion between the glass substrate and the first resin layer and the third resin layer.

The material of the primer layer is not particularly limited as long as it is a material capable of enhancing the adhesion between the glass base material and the first resin layer or the third resin layer, and examples thereof include a resin. Examples of the resin include (meth) acrylic resin, urethane resin, (meth) acrylic urethane copolymer, vinyl chloride-vinyl acetate copolymer, polyester, butyral resin, chlorinated polypropylene, chlorinated polyethylene, epoxy resin, and silicone. Examples include resin. These resins may be used alone or in combination of two or more.

Further, a silane coupling agent such as an alkoxysilane compound may be added to the primer layer composition used for forming the primer layer.

The thickness of the primer layer may be any thickness as long as it can enhance the adhesion between the glass substrate and the first resin layer or the third resin layer, and may be, for example, 0.1 μm or more and 10 μm or less. It can be preferably 0.2 μm or more and 5 μm or less.

Examples of the method for forming the primer layer include a method of applying a primer layer composition on a glass substrate. As the coating method, for example, general gravure coating method, gravure reverse coating method, gravure offset coating method, spin coating method, roll coating method, reverse roll coating method, blade coating method, dip coating method, screen printing method and the like are used. The coating method can be mentioned. Further, a transfer method can also be used as a method for forming the primer layer.

(2) Third Resin Layer As shown in FIG. 12, for example, the glass laminate in the present disclosure has a third resin layer on the surface side of the glass substrate 2 opposite to the first resin layer 3, that is, on the second surface side. 6 may be possessed. When an impact is applied to the glass laminate, not only the first resin layer but also the third resin layer can absorb the impact, suppress the cracking of the glass base material, and improve the impact resistance.

Since the characteristics and materials of the third resin layer can be the same as those of the first resin layer, the description thereof is omitted here.

The thickness of the third resin layer may be any thickness as long as it can absorb impact, and is preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more and 75 μm or less, and further preferably 15 μm or more. It can be 50 μm or less.

The method for forming the third resin layer can be the same as the method for forming the first resin layer.

(3) Decorative layer In the glass laminate in the present disclosure, a decorative layer is provided between the glass base material and the first resin layer, or on the surface side of the glass base material opposite to the first resin layer. You may have.

The decorative layer contains a colorant and a binder resin. The binder resin contained in the decorative layer is not particularly limited, and a resin used for a general decorative layer can be used. The colorant contained in the decorative layer is not particularly limited, and a known colorant used for a general decorative layer can be used.

The decorative layer is usually placed on a portion of the glass substrate. Further, the decorative layer may have a pattern shape.

The thickness of the decorative layer is not particularly limited, but can be, for example, 5 μm or more and 40 μm or less.

6. Characteristics of Glass Laminate The glass laminate in the present disclosure preferably has a total light transmittance of, for example, 82% or more, more preferably 85% or more, and further preferably 88% or more. The upper limit is 100%. Due to the high total light transmittance as described above, a glass laminate having good transparency can be obtained.

Here, the total light transmittance of the glass laminate can be measured according to JIS K7361-1, and can be measured by, for example, a haze meter HM150 manufactured by Murakami Color Technology Research Institute.

The haze of the glass laminate in the present disclosure is, for example, preferably 1.0% or less, more preferably 0.8% or less, still more preferably 0.5% or less. With such a low haze, it is possible to obtain a glass laminate having good transparency. The lower limit of haze is 0%.

Here, the haze of the glass laminate can be measured according to JIS K-7136, and can be measured by, for example, a haze meter HM150 manufactured by Murakami Color Technology Laboratory.

The glass laminate in the present disclosure preferably has bending resistance. Specifically, in the bending test by the cylindrical mandrel method, the minimum diameter of the mandrel in which the glass laminate is cracked is preferably 10 mm or less, and more preferably 5 mm or less. .. If the minimum diameter of the mandrel is in the above range, the bending resistance can be further improved. The bending test by the cylindrical mandrel method will be described in detail in Examples described later, and thus the description thereof will be omitted here.

Further, in the glass laminate in the present disclosure, it is preferable that the glass laminate does not crack or break when the dynamic bending test described below is repeated 200,000 times.

In the dynamic bending test, the glass laminate may be folded so that the glass substrate is on the outside, or the glass laminate may be folded so that the glass substrate is on the inside. , It is preferable that the glass laminate does not crack or break.

The dynamic bending test is performed as follows. As shown in FIG. 13A, in the dynamic bending test, first, the short side portion 1C of the glass laminate 1 having a size of 20 mm × 100 mm and the short side portion 1D facing the short side portion 1C are formed. Each is fixed by the fixing portions 21 arranged in parallel.

Further, as shown in FIG. 13A, the fixing portion 21 is slidable in the horizontal direction. Next, as shown in FIG. 13 (b), by moving the fixing portions 21 so as to be close to each other, the glass laminate 1 is deformed so as to be folded, and further, as shown in FIG. 13 (c). After moving the fixing portion 21 to a position where the distance d between the two opposing short side portions 1C and 1D fixed by the fixing portion 21 of the glass laminate 1 becomes a predetermined value, the fixing portion 21 is moved in the opposite direction. The deformation of the glass laminate 1 is eliminated. By moving the fixing portion 21 as shown in FIGS. 13 (a) to 13 (c), the glass laminate 1 can be folded by 180 °. Further, by performing a dynamic bending test so that the bent portion 1E of the glass laminate 1 does not protrude from the lower end of the fixed portion 21, and controlling the interval d when the fixed portions 21 are closest to each other, the glass laminate 1 is formed. The distance d between the two opposing short side portions 1C and 1D of 1 can be set to a predetermined value. For example, when the distance d between the two short side portions 1C and 1D facing each other is 10 mm, the outer diameter of the bent portion 1E is regarded as 10 mm.

In the glass laminate, it is preferable that cracking or breakage does not occur when the 180 ° folding test is repeated 200,000 times so that the distance d between the opposing short side portions 1C and 1D of the glass laminate 1 is 8 mm. ..

Further, in the glass laminate in the present disclosure, when the static bending test described below is performed on the glass laminate, the opening angle θ after the static bending test in the glass laminate is 100 ° or more. It is preferably 130 ° or more, and more preferably 130 ° or more.

The static bending test is performed as follows. First, as shown in FIG. 14A, the short side portion 1C of the glass laminate 1 and the short side portion 1D facing the short side portion 1C are separated from each other by the distance d between the short side portion 1C and the short side portion 1D. Each is fixed by the fixing portions 22 arranged in parallel so that the height is 10 mm. Then, a static bending test is performed in which the glass laminate 1 is allowed to stand at 23 ° C. for 240 hours in a folded state. Then, as shown in FIG. 14B, the fixed portion 22 is removed from the short side portion 1D after the static bending test to open the folded state, and the glass laminate 1 naturally becomes formed after 30 minutes at room temperature. The opening angle θ, which is the opening angle, is measured. The larger the opening angle θ, the better the stability, and the maximum is 180 °.

In the static bending test, the glass laminate may be folded so that the glass substrate is on the inside, or the glass laminate may be folded so that the glass substrate is on the outside. In either case. The opening angle θ is preferably 100 ° or more, and more preferably 130 ° or more.

7. Applications of the glass laminate The glass laminate in the present disclosure can be used as a member arranged on the observer side of the display panel in the display device. The glass laminate in the present disclosure can be used for display devices used in electronic devices such as smartphones, tablet terminals, wearable terminals, personal computers, televisions, digital signage, public information displays (PIDs), and in-vehicle displays. .. Above all, the glass laminate in the present disclosure can be preferably used for a flexible display such as a foldable display, a rollable display, and a bendable display, and can be preferably used for a foldable display.

When the glass laminate in the present disclosure is arranged on the surface of the display device, the surface on the glass substrate side is arranged on the display panel side and the surface on the first resin layer side is on the outside.

The method of arranging the glass laminate on the surface of the display device in the present disclosure is not particularly limited, and examples thereof include a method via an adhesive layer. As the adhesive layer, a known adhesive layer used for adhering the glass laminate can be used.

B. Display device The display device in the present disclosure includes a display panel and the above-mentioned glass laminate arranged on the observer side of the display panel.

FIG. 15 is a schematic cross-sectional view showing an example of the display device in the present disclosure. As shown in FIG. 15, the display device 30 includes a display panel 31 and a glass laminate 1 arranged on the observer side of the display panel 31. In the display device 30, the glass laminate 1 is used as a member arranged on the surface of the display device 30, and an adhesive layer 32 is arranged between the glass laminate 1 and the display panel 31.

The glass laminate in the present disclosure can be the same as the above-mentioned glass laminate.

Examples of the display panel in the present disclosure include display panels used in display devices such as liquid crystal displays, organic EL display devices, and LED display devices.

The display device in the present disclosure may have a touch panel member between the display panel and the glass laminate.

The display device in the present disclosure is preferably a flexible display. Above all, the display device in the present disclosure is preferably foldable. That is, the display device in the present disclosure is more preferably a foldable display. Since the display device in the present disclosure has the above-mentioned glass laminate, it is excellent in impact resistance and bending resistance, and is suitable as a flexible display and further as a foldable display.

C. Electronic Equipment The electronic equipment in the present disclosure includes the above-mentioned display device.

The electronic device in the present disclosure is not particularly limited as long as it is provided with the above-mentioned display device, and is, for example, a smartphone, a tablet terminal, a wearable terminal, a personal computer, a television, a digital signage, or a public information display (PID). ), In-vehicle display and the like.

D. Resin layer The resin layer in the present disclosure is a resin layer arranged on the main surface side of a glass substrate having a thickness of 100 μm or less and used to cover the side surface of the glass substrate, and is transparent. Has.

When the resin layer in the present disclosure is arranged on the main surface side of a glass substrate having a predetermined thickness and is used by covering the side surface of the glass substrate, the above-mentioned "A. glass laminate" is used. As described in the section, good bending resistance and impact resistance can be obtained.

Regarding the resin layer in the present disclosure, in the above-mentioned glass laminate, the first resin layer and the second resin layer contain the same material, and the second resin layer and the third resin layer contain the same material in an integral manner. However, it can be the same as the embodiment in which the second resin layer and the functional layer contain the same material and are integrated. Above all, it is preferable that the resin layer is an embodiment in which the first resin layer and the second resin layer contain the same material and are integrated in the above-mentioned glass laminate.

As a method of arranging the resin layer on the main surface of the glass substrate and arranging it so as to cover the side surface of the glass substrate, for example, a film-like film is formed on the main surface and the side surface of the glass substrate via an adhesive layer. An example is a method of laminating resin layers.

The present disclosure is not limited to the above embodiment. The above embodiment is an example, and any object having substantially the same structure as the technical idea described in the claims of the present disclosure and having the same effect and effect is the present invention. Included in the technical scope of the disclosure.

Hereinafter, the present disclosure will be further described with reference to Examples and Comparative Examples.

[Comparative Example 1]
(Glass substrate)
A chemically strengthened glass substrate having a thickness of 70 μm was used. In this glass base material, the end face of the glass base material was processed, and the shape of the end portion of the glass base material was as shown in FIG. 2 (a).

[Comparative Example 2]
(Formation of resin layer)
Using the same glass base material as in Comparative Example 1, a resin composition (manufactured by Byron UR-4800 Toyobo Co., Ltd.) containing a urethane-modified copolymerized polyester resin was formed on the main surface of the glass base material to a predetermined thickness. A resin layer was formed. The drying conditions for forming the resin layer were 100 ° C. for 3 minutes. Further, when forming the resin layer, a film slightly larger than the glass base material is bonded to the second surface opposite to the main surface (first surface) forming the resin layer of the glass base material. The resin composition was applied to a carrier glass having a thickness of 0.7 mm so that the surface on the glass substrate side was on the upper side, and the resin composition was applied by the die coating method. At that time, in the die coater, a nozzle having a nozzle width smaller than the width of the glass base material was used to prevent the resin composition from being applied to the side surface of the glass base material.

[Example 1]
(Formation of resin layer)
In Comparative Example 2, when forming the resin layer, the resin composition was applied to the main surface and the side surface of the glass substrate by using a nozzle having a nozzle width larger than the width of the glass substrate in the die coater. Except for this, a resin layer was formed on the main surface and the side surface of the glass substrate in the same manner as in Comparative Example 2.

[Comparative Example 3]
(Glass substrate)
A chemically strengthened glass substrate having a thickness of 70 μm was used. In this glass base material, the end face of the glass base material was unprocessed, and the shape of the end portion of the glass base material was as shown in FIG. 2 (b).

[Comparative Example 4]
(Formation of resin layer)
The same glass base material as in Comparative Example 3 was used, and the resin layer was formed on the main surface of the glass base material in the same manner as in Comparative Example 2 except that the thickness of the resin layer was changed.

[Comparative Example 5]
(Formation of primer layer)
Using the same glass substrate as in Comparative Example 1, the following composition for a primer layer was coated on the glass substrate and dried at 80 ° C. for 3 minutes and at 150 ° C. for 60 minutes to obtain a primer layer having a thickness of 1 μm. Formed.

<Composition for primer layer>
・ Bisphenol A type solid epoxy resin (jER1256B40 manufactured by Mitsubishi Chemical) 28 parts by mass ・ Bisphenol A novolak type solid epoxy resin (jER157S65B80 manufactured by Mitsubishi Chemical) 5 parts by mass ・ 2-ethyl-4-methylimidazole (manufactured by Tokyo Chemical Industry) 1 mass Parts / solvent (MEK) 11 parts by mass

(Formation of resin layer)
With reference to Synthesis Example 1 of WO2014 / 046180, a tetracarboxylic dianhydride represented by the following chemical formula was synthesized.

Dehydrated N, N-dimethylacetamide (DMAc) (1833.2 g) and 2,2'-bis (trifluoromethyl) benzidine (TFMB) (138.48 g) were dissolved in a 5 L separable flask. The solution was added and the tetracarboxylic acid dianhydride (TMPBPTME) (176.70 g) represented by the above chemical formula was gradually added to a place where the temperature was controlled to 30 ° C. so that the temperature rise was 2 ° C or lower. It was charged and stirred with a mechanical stirrer for 30 minutes. Pyromytzic acid dianhydride (PMDA) (64.20 g) was gradually added thereto in several portions so that the temperature rise was 2 ° C. or lower, and the polyimide precursor solution (solid) in which the polyimide precursor was dissolved was added. Minutes 18% by mass) was synthesized. The molar ratio of TMPBPTME to PMDA (TMPBPTME: PMDA) of the tetracarboxylic dianhydride used in the polyimide precursor was 90:10. The weight average molecular weight of the polyimide precursor was 75,000.

The above-mentioned polyimide precursor solution (2162 g) cooled to room temperature was added to a 5 L separable flask under a nitrogen atmosphere. Dehydrated N, N-dimethylacetamide (432 g) was added thereto, and the mixture was stirred until uniform. Next, the catalyst pyridine (6.622 g) and acetic anhydride (213.67 g) were added and stirred at room temperature for 24 hours to synthesize a polyimide solution.

N, N-dimethylacetamide (DMAc) (2000 g) was added to the obtained polyimide solution, and the mixture was stirred until uniform. Next, the polyimide solution was divided into 3 equal parts in a 5 L beaker and transferred, and isopropyl alcohol (3500 g) was gradually added to each beaker to obtain a white slurry. The above slurry was transferred onto a Büchner funnel, filtered, then flushed with isopropyl alcohol (9000 g in total) for washing, and then filtered. The process was repeated three times, dried at 110 ° C. using a vacuum dryer, and polyimide (polyimide). Polyimide powder) was obtained. The weight average molecular weight of the polyimide measured by GPC was 100,000.

N, N-dimethylacetamide (DMAc) was added to the polyimide so that the solid content concentration of the polyimide was 12% by mass to prepare a polyimide varnish (resin composition) having 12% by mass of the polyimide in the varnish. The viscosity of the polyimide varnish (resin composition) (solid content concentration 12% by mass) at 25 ° C. was 15000 cps.

The polyimide varnish (resin composition) is applied onto the primer layer to a predetermined thickness, dried at 80 ° C. for 5 minutes, at 150 ° C. for 10 minutes, and at 230 ° C. for 30 minutes to obtain a predetermined thickness. A resin layer was formed. When forming the resin layer, a film slightly larger than the glass substrate is bonded to the second surface opposite to the main surface (first surface) forming the resin layer of the glass substrate, and then the glass is formed. It was attached to a carrier glass having a plate thickness of 0.7 mm so that the surface on the substrate side was on the upper side, and the above resin composition was applied by a die coating method. At that time, in the die coater, a nozzle having a nozzle width smaller than the width of the glass base material was used to prevent the resin composition from being applied to the side surface of the glass base material.

[Example 2]
(Formation of resin layer)
In Comparative Example 5, when forming the resin layer, the resin composition was applied to the main surface and the side surface of the glass substrate by using a nozzle having a nozzle width larger than the width of the glass substrate in the die coater. Except for this, a resin layer was formed on the main surface and the side surface of the glass substrate in the same manner as in Comparative Example 5.

[Example 3]
(Formation of resin layer)
In Example 2, the resin layer was applied to the main surface and the side surface of the glass substrate in the same manner as in Example 2 except that the resin composition was applied by the spin coating method and the thickness of the resin layer was changed. Formed.

[Example 4]
(Formation of resin layer)
In Example 3, the resin layer was formed on the main surface and the side surface of the glass substrate in the same manner as in Example 3 except that the thickness of the resin layer was changed.

[Example 5]
A resin layer is formed on the main surface and the side surface of the glass substrate in the same manner as in Example 4 except that the chemically strengthened glass substrate having the surface compressive stress value (CS) shown in Table 1 below is used. bottom.

[Example 6]
In Example 5, the resin layer was formed on the main surface and the side surface of the glass substrate in the same manner as in Example 5 except that the thickness of the second resin layer was changed.

[Example 7]
In Example 5, the resin layer was formed on the main surface and the side surface of the glass substrate in the same manner as in Example 5 except that the thickness of the second resin layer was changed.

[evaluation]
(1) Bending test (mandrel test)
Bending tests were performed on the glass laminates of Examples 1 to 5 and Comparative Examples 2, 4 and 5, and the glass substrates of Comparative Examples 1 and 3. By imitating the cylindrical mandrel method described in JIS-K5600-5-1, a sample piece (100 mm × 50 mm) is wound around a mandrel having a diameter of 2 mm to 32 mm to form a glass laminate or a glass substrate. Flexibility was evaluated.
At this time, the glass laminate was wound around the mandrel so that the first resin layer was on the inside and the glass substrate was on the outside. Table 1 shows the minimum diameter of the mandrel in which the glass laminate or the glass substrate is cracked. The smaller the value, the higher the bending resistance. The results of the bending test were evaluated according to the following criteria.
A: The minimum diameter of the mandrel in which the glass laminate or the glass substrate is cracked is 5 mm or less.
B: The minimum diameter of the mandrel in which the glass laminate or the glass substrate is cracked is 6 mm or more and 10 mm or less.
C: The minimum diameter of the mandrel in which the glass laminate or the glass substrate is cracked is 12 mm or more.

(2) Impact test (pen drop test)
Impact tests were performed on the glass laminates of Examples 1 to 5 and Comparative Examples 2, 4 and 5, and the glass substrates of Comparative Examples 1 and 3. First, an optical adhesive film (OCA) having a thickness of 50 μm and a PET film having a thickness of 100 μm were laminated in this order on the surface of the glass substrate of the glass laminate or the glass substrate to prepare a test laminate. .. The test laminate was placed on the metal plate so that the PET film side of the test laminate was in contact with the metal plate having a thickness of 30 mm. Next, with respect to the central portion and the end portion of the test laminate, the pen was dropped onto the test laminate with the tip of the pen facing down from the test height, respectively. Here, the end portion of the test laminate indicates a region within 5 mm from the end portion of the glass substrate. Further, the central portion of the test laminate indicates a region other than the end portion of the test laminate.
As the pen, Bren 0.5BAS88-BK (weight 12 g, pen tip 0.5 mmφ) manufactured by Zebra was used. Table 1 shows the maximum test height at which the glass substrate did not crack. The larger the value, the higher the impact resistance. The results of the impact test were evaluated according to the following criteria.
A: The maximum test height at which the glass substrate did not crack is 12 cm or more.
B: The maximum test height at which the glass substrate was not cracked was 8 cm or more and less than 12 cm.
C: The maximum test height at which the glass substrate did not crack is less than 8 cm.

(3) Total light transmittance and haze The total light transmittance and haze of the glass laminates of Examples 1 to 5 were measured. The total light transmittance was measured by a haze meter (HM150 manufactured by Murakami Color Technology Research Institute) in accordance with JIS K7361-1. The haze was measured by a haze meter (HM150 manufactured by Murakami Color Technology Research Institute) in accordance with JIS K-7136.

(4) Surface compressive stress value (CS) of chemically strengthened glass
The surface compressive stress values of the glass substrates in Examples 1 to 5 and Comparative Examples 1 to 5 were measured using a refractometer type glass surface stress meter FSM-6000LE manufactured by Luceo.

In Table 1, the resin layer formed on the main surface of the glass substrate is referred to as the first resin layer, and the resin layer formed on the side surface of the glass substrate is referred to as the second resin layer. Further, the thickness T2 of the second resin layer is the thickness of the second resin layer in the direction parallel to the main surface of the glass base material, and the thickness T4 of the second resin layer is the thickness direction of the glass base material. It is the thickness of the second resin layer in. In addition, the coverage ratio is such that the ratio of T1 / T2 on the four sides of the glass base material is 0.01 or more and 5.0 or less when the total length of the four sides when the glass base material is viewed in a plan view is 100%. Is the ratio.

From Comparative Examples 1 and 2, when the first resin layer is arranged on the main surface side of the glass substrate, but the side surface of the glass substrate is not covered with the second resin layer (Comparative Example 2), it is resistant. Although the impact resistance was good, it was confirmed that the bending resistance was worse than that of the glass base material alone (Comparative Example 1). Similarly, from Comparative Examples 3 and 4, when the first resin layer is arranged on the main surface side of the glass substrate, but the side surface of the glass substrate is not covered with the second resin layer (Comparative Example 4). Although the impact resistance was good, it was confirmed that the bending resistance was worse than that of the glass base material alone (Comparative Example 3). Similarly, in Comparative Example 5, the first resin layer is arranged on the main surface side of the glass substrate, but the side surface of the glass substrate is not covered with the second resin layer, so that the impact resistance is improved. Although it was good, it was inferior in bending resistance.

On the other hand, in Examples 1 to 4, since the first resin layer is arranged on the main surface side of the glass substrate and the side surface of the glass substrate is covered with the second resin layer, good bending resistance is obtained. Properties and impact resistance were obtained.

1 ... Glass laminate 2 ... Glass base material 2P ... Main surface of glass base material 2S ... Side surface of glass base material 3 ... First resin layer 4 ... Second resin layer 5 ... Hard coat layer 6 ... Third resin layer 8 ... Primer layer 30 ... Display device 31 ... Display panel

Claims (21)

A glass laminate having a glass base material, a first resin layer, and a second resin layer.
The glass substrate has a first surface, a second surface opposite to the first surface, and a third surface different from the first surface and the second surface.
The thickness of the glass substrate is 100 μm or less, and the thickness is 100 μm or less.
The first resin layer exists on the first surface side and has transparency.
A glass laminate in which the second resin layer covers the third surface. The glass laminate according to claim 1, wherein the first resin layer and the second resin layer contain the same material and are integrated. The glass laminate according to claim 1 or 2, wherein (Equation 1) is satisfied when the thickness of the first resin layer is T1 and the thickness of the second resin layer is T2.
(Equation 1) 0.01 ≤ T1 / T2 ≤ 5.0 The claim according to any one of claims 1 to 3, wherein the ratio of the thickness of the second resin layer to the thickness of the glass substrate in the thickness direction of the glass substrate is 0.5 or more. The glass laminate according to the item. The invention according to any one of claims 1 to 4, wherein the first resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin. Glass laminate. The second resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin, or contains a cured product of a resin composition containing a polymerizable compound. , The glass laminate according to any one of claims 1 to 5. The glass laminate according to any one of claims 1 to 6, further comprising a primer layer between the glass substrate and the first resin layer. The glass laminate according to any one of claims 1 to 7, which has a functional layer on the surface side of the first resin layer opposite to the glass substrate. The glass laminate according to claim 8, wherein the second resin layer and the functional layer contain the same material and are integrated. The glass laminate according to claim 8 or 9, wherein the functional layer is a hard coat layer, and the hard coat layer contains a cured product of a resin composition containing a polymerizable compound. The glass laminate according to any one of claims 1 to 10, further comprising a third resin layer on the surface side of the glass substrate opposite to the first resin layer. The glass laminate according to claim 11, wherein the third resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide-based resin, epoxy resin, and acrylic resin. The glass laminate according to claim 11 or 12, wherein the second resin layer and the third resin layer contain the same material and are integrated. The glass laminate according to any one of claims 1 to 13, wherein the glass substrate is chemically tempered glass. The glass laminate according to any one of claims 1 to 14, wherein the first resin layer has a total light transmittance of 82% or more and a haze of 1.0% or less. The glass laminate according to any one of claims 1 to 15, wherein the total light transmittance is 82% or more and the haze is 1.0% or less. Display panel and
The glass laminate according to any one of claims 1 to 16, which is arranged on the observer side of the display panel, and the glass laminate.
Display device. An electronic device comprising the display device according to claim 17. A resin layer arranged on the main surface side of a glass substrate having a thickness of 100 μm or less and used for covering the side surface of the glass substrate.
A transparent resin layer. Claimed that the resin layer contains at least one selected from the group consisting of polyurethane, polyester, polyimide resin, epoxy resin and acrylic resin, or contains a cured product of a resin composition containing a polymerizable compound. Item 19. The resin layer according to Item 19. The resin layer according to claim 19 or 20, wherein the total light transmittance is 82% or more and the haze is 1.0% or less.

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