JP2020044651A - Glass laminate - Google Patents

Abstract

To provide a glass laminate capable of preventing a curl from occurring and capable of preventing a glass substrate from being damaged.SOLUTION: A glass laminate 1 includes: a carrier film 2; and a glass substrate 3 arranged on an upper side thereof and having thickness of 150 μm or less. In the glass laminate 1, the carrier film 2 includes a plastic substrate 4 having thickness of 100 μm or less, and an adhesive layer 5 arranged on an upper side thereof; and when the glass laminate 1 is heated at 140°C for 60 minutes, the peel force of the carrier film 2 and the glass substrate 3 is 0.1 N/50 mm or more and 2.0 N/50 mm or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a glass laminate, and more particularly, to a glass laminate suitably used for optical applications.

  In recent years, a thin glass substrate is being used as a flexible substrate of an optical film provided in an image display device such as a liquid crystal display and an organic EL display from the viewpoint of heat resistance and the like. Specifically, a transparent conductive film in which a transparent conductive layer such as indium tin oxide (ITO) is formed on a thin glass substrate is used as a touch panel film.

  In order to mass-produce such an optical film, a roll-to-roll method is adopted. That is, a long thin glass substrate is prepared, a functional layer such as a transparent conductive layer is sequentially formed on the thin glass substrate, and finally, the thin glass substrate is wound into a roll.

 However, when an optical film including a thin glass substrate is wound, the thin glass substrate is damaged by stress between the thin glass substrates stacked in the thickness direction. Therefore, a glass laminate with a resin layer in which an adhesive layer and a resin layer are laminated on a thin glass substrate has been proposed (see Patent Document 1).

JP 2017-39227 A

  However, in Patent Document 1, since the resin layer is laminated on the thin glass substrate via the adhesive layer, the resin layer cannot be separated from the thin glass substrate. Therefore, since the resin layer remains as a final product (optical film), it is not possible to reduce the thickness of the optical film, and the optical characteristics (light transmittance and color) may be reduced.

  Therefore, a method of laminating a carrier film composed of an adhesive layer and a plastic film on a thin glass substrate of an optical film is studied. Since this carrier film is laminated on the thin glass substrate via the pressure-sensitive adhesive layer, it is easily removed (peeled) at the pressure-sensitive adhesive layer as a boundary after the optical film is manufactured and before being incorporated into an image display device. be able to.

  By the way, depending on the type of the optical film, a heat treatment may be performed at the time of producing the optical film. For example, in an optical film in which a transparent conductive layer such as ITO is formed on a thin glass substrate, a heat treatment is performed for crystallization (resistance reduction).

  Then, curling occurs due to the difference in the coefficient of thermal expansion between the thin glass substrate and the carrier film. Therefore, it is considered to reduce the curl by making the carrier film thinner.

  However, when the laminate of the thin film carrier film and the thin glass substrate is heated, when the carrier film is removed, the carrier film does not peel off smoothly from the thin glass substrate, and the thin glass substrate is damaged. Occurs.

  An object of the present invention is to provide a glass laminate capable of suppressing the occurrence of curl and preventing the breakage of a glass substrate.

  The present invention [1] is a glass laminate including a carrier film and a glass substrate having a thickness of 150 μm or less, which is disposed on one side in the thickness direction of the carrier film, wherein the carrier film has a thickness of 100 μm. The following plastic substrate, comprising a pressure-sensitive adhesive layer disposed on one side in the thickness direction of the plastic substrate, when the glass laminate is heated at 140 ℃ 60 minutes, the carrier film and the glass substrate And a glass laminate having a peel force of 0.1 N / 50 mm or more and 2.0 N / 50 mm or less.

  The present invention [2] includes the glass laminate according to [1], further including a transparent conductive layer disposed on one side in the thickness direction of the glass substrate.

  The present invention [3] includes the glass laminate according to [1] or [2], which is wound in a roll shape.

  Since the glass laminate of the present invention includes a glass substrate having a thickness of 150 μm or less, it can be formed into a roll, and industrial production (mass production) by a roll-to-roll method is possible.

  In addition, since the glass laminate of the present invention includes the carrier film and the glass substrate, when the glass laminate is rolled, breakage of the glass substrate can be suppressed.

  In addition, since the carrier film includes the plastic substrate having a thickness of 100 μm or less and the pressure-sensitive adhesive layer, curling in the heat treatment can be suppressed.

  Further, when the glass laminate of the present invention is heated at 140 ° C. for 60 minutes, the peeling force between the carrier film and the glass substrate is 0.1 N / 50 mm or more and 2.0 N / 50 mm or less. Also, the carrier film can be smoothly separated from the glass substrate. Therefore, breakage of the glass substrate can be suppressed when the carrier film is peeled off.

FIG. 1 shows a cross-sectional view of one embodiment of the glass laminate of the present invention. FIG. 2 is a sectional view of a transparent conductive glass laminate including the glass laminate shown in FIG. FIG. 3 shows a perspective view of a roll body of the transparent conductive glass laminate shown in FIG. FIG. 4 is a schematic view of a test for measuring a peeling force of a glass laminate in an example. FIG. 5 is a schematic view of a test for measuring the curl of the glass laminate in the example.

<One embodiment>
A glass laminate 1 according to an embodiment of the present invention will be described with reference to FIGS.

  In FIG. 1, the vertical direction of the paper is the vertical direction (thickness direction), the upper side of the paper is the upper side (one side in the thickness direction), and the lower side of the paper is the lower side (the other side in the thickness direction). In FIG. 1, the left-right direction and the depth direction of the drawing are plane directions orthogonal to the up-down direction. Specifically, it conforms to the directional arrows in each figure.

1. Glass Laminate As shown in FIG. 1, the glass laminate 1 has flexibility and a film shape (including a sheet shape) having a predetermined thickness. The glass laminate 1 extends in a plane direction orthogonal to the vertical direction (thickness direction), and has a flat upper surface (a surface on one side in the thickness direction) and a flat lower surface (a surface on the other side in the thickness direction). The glass laminate 1 is, for example, one component for producing a touch panel base material provided in the image display device, that is, is not an image display device. That is, the glass laminate 1 is a device which does not include an image display element such as an LCD module, is distributed as a single component, and is industrially usable.

  Specifically, the glass laminate 1 includes a carrier film 2 and a glass substrate 3 disposed on the upper surface thereof. That is, the glass laminate 1 includes the carrier film 2 and the glass substrate 3 in order from the bottom. Preferably, the glass laminate 1 includes a carrier film 2 and a glass substrate 3. Hereinafter, each member will be described in detail.

2. Carrier Film The carrier film 2 is formed of a glass base material 3 and a transparent conductive glass 6 when transported, heated and / or stored. It is a protection member provided on the lower surface. The carrier film 2 supports the glass substrate 3 from below.

  The carrier film 2 has a film shape having a predetermined thickness, extends in the surface direction, and has a flat upper surface and a flat lower surface. The carrier film 2 is arranged below the glass laminate 1, and specifically, is arranged on the entire lower surface of the glass substrate 3 so as to contact the lower surface of the glass substrate 3.

  Specifically, the carrier film 2 includes a plastic substrate 4 and an adhesive layer 5 disposed on the upper surface of the plastic substrate 4. That is, the carrier film 2 includes the plastic substrate 4 and the pressure-sensitive adhesive layer 5 in order from the bottom. Preferably, the carrier film 2 includes a plastic substrate 4 and an adhesive layer 5.

(Plastic substrate)
The plastic substrate 4 is a supporting substrate for securing the mechanical strength of the carrier film 2 and protecting the glass substrate 3 from being damaged during transportation, heating, and / or storage.

  The plastic substrate 4 has a film shape and is provided on the lowermost layer of the glass laminate 1.

  The plastic substrate 4 is, for example, a polymer film having flexibility. Examples of the material of the plastic substrate 4 include polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate; for example, (meth) acrylic resins (acrylic resin and / or methacrylic resin) such as polymethacrylate; For example, polyethylene, polypropylene, olefin resins such as cycloolefin polymers (for example, norbornene-based, cyclopentadiene-based), for example, polycarbonate resin, polyether sulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, cellulose resin, Polystyrene resin and the like can be mentioned. These materials can be used alone or in combination of two or more.

  From the viewpoint of transparency, heat resistance, mechanical strength, and the like, preferably, a polyester resin is used, and more preferably, PET is used.

  The thickness of the plastic substrate 4 is 100 μm or less, preferably 60 μm or less, and more preferably 35 μm or less. In addition, for example, it is 5 μm or more, preferably 10 μm or more. When the thickness of the plastic substrate 4 is equal to or less than the upper limit, the occurrence of curling when the glass laminate 1 is heated can be suppressed. On the other hand, when the thickness of the plastic substrate 4 is equal to or more than the above lower limit, the mechanical strength is excellent, and the breakage of the glass substrate 3 can be suppressed.

  The thickness of the plastic substrate 4 can be measured using a dial gauge (“DG-205” manufactured by PEACOCK).

(Adhesive layer)
The pressure-sensitive adhesive layer 5 is a layer (pressure-sensitive adhesive layer) for adhering the plastic substrate 4 to the glass substrate 3, and is easily peeled off from the glass substrate 3 after adhering. Layer (easily peelable layer).

  The pressure-sensitive adhesive layer 5 has a film shape and is arranged on the entire upper surface of the plastic substrate 4 so as to be in contact with the upper surface of the plastic substrate 4. Specifically, the pressure-sensitive adhesive layer 5 is disposed between the plastic substrate 4 and the glass substrate 3 so as to contact the upper surface of the plastic substrate 4 and the lower surface of the glass substrate 3. Specifically, the pressure-sensitive adhesive layer 5 is pressure-sensitively bonded to the lower surface of the glass substrate 3.

  The pressure-sensitive adhesive layer 5 is formed from a pressure-sensitive adhesive composition.

  Examples of the pressure-sensitive adhesive composition include an acrylic pressure-sensitive adhesive composition, a rubber-based pressure-sensitive adhesive composition, a silicone-based pressure-sensitive adhesive composition, a polyester-based pressure-sensitive adhesive composition, a polyurethane-based pressure-sensitive adhesive composition, and a polyamide-based pressure-sensitive adhesive composition. , An epoxy-based pressure-sensitive adhesive composition, a vinylalkylether-based pressure-sensitive adhesive composition, a fluorine-based pressure-sensitive adhesive composition, and the like. These pressure-sensitive adhesive compositions can be used alone or in combination of two or more.

  The pressure-sensitive adhesive composition is preferably an acrylic pressure-sensitive adhesive composition from the viewpoint of adhesion before heating, peelability after heating, and the like.

  The acrylic pressure-sensitive adhesive composition contains, for example, an acrylic polymer obtained by polymerizing a monomer component containing an alkyl (meth) acrylate as a polymer component.

  The alkyl (meth) acrylate is an alkyl acrylate and / or an alkyl methacrylate, specifically, for example, butyl (meth) acrylate, isobutyl (meth) acrylate, sec (meth) acrylate -Butyl, t-butyl (meth) acrylate, pentyl (meth) acrylate, neopentyl (meth) acrylate, isopentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, (meth) Linear or branched, having 4 to 4 carbon atoms, such as 2-ethylhexyl acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, and tetradecyl (meth) acrylate; (Meth) acrylic acid alkyl esters having 14 alkyl moieties and the like It is. The alkyl (meth) acrylates can be used alone or in combination of two or more.

  As the alkyl (meth) acrylate, preferably, an alkyl (meth) acrylate having an alkyl moiety having 4 to 12 carbon atoms is used, and more preferably, an alkyl moiety having 6 to 10 carbon atoms is preferably used. Examples thereof include alkyl (meth) acrylates, and more preferably include 2-ethylhexyl (meth) acrylate.

  The compounding ratio of the alkyl (meth) acrylate is, for example, 90 parts by mass or more, preferably 95 parts by mass or more, and for example, 99 parts by mass or less, based on 100 parts by mass of the total amount of the monomer components. Is 98 parts by mass or less. By adjusting the mixing ratio of the alkyl (meth) acrylate, the peeling force of the pressure-sensitive adhesive layer 5 can be adjusted.

  The monomer component may contain a functional group-containing monomer in addition to the alkyl (meth) acrylate.

  Examples of the functional group-containing monomer include a carboxyl group-containing monomer such as acrylic acid and methacrylic acid, and a hydroxyl group-containing monomer such as 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate. The functional group-containing monomers can be used alone or in combination of two or more.

  The functional group-containing monomer is preferably a hydroxyl group-containing monomer, and more preferably 2-hydroxyethyl acrylate, from the viewpoint of adhesion before heating and releasability after heating.

  The blending ratio of the functional group-containing monomer is, for example, 1 part by mass or more, preferably 2 parts by mass or more, and for example, 10 parts by mass or less, preferably 5 parts by mass in 100 parts by mass of the total amount of the monomer components. It is as follows.

  The weight average molecular weight of the acrylic polymer is, for example, 100,000 or more, preferably 300,000 or more, and for example, 2,000,000 or less, preferably 1,000,000 or less. The weight average molecular weight can be measured by gel permeation chromatography based on a standard polystyrene equivalent value.

  The acrylic pressure-sensitive adhesive composition can be obtained by a known method such as solution polymerization, bulk polymerization, and photopolymerization.

  The pressure-sensitive adhesive composition preferably contains a crosslinking agent. Examples of the crosslinking agent include an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, a melamine-based resin, an aziridine derivative, and a metal chelate compound. These crosslinking agents can be used alone or in combination of two or more.

  The crosslinking agent is preferably an isocyanate-based crosslinking agent or an epoxy-based crosslinking agent, and more preferably an isocyanate-based crosslinking agent.

  As the isocyanate-based crosslinking agent, for example, aromatic isocyanates such as toluene diisocyanate and xylene diisocyanate, for example, cycloaliphatic isocyanates such as cyclopentylene diisocyanate and cyclohexylene diisocyanate, for example, aliphatic isocyanates such as butylene diisocyanate and hexamethylene diisocyanate For example, isocyanate adducts such as trimethylolpropane / tolylene diisocyanate trimer adduct, trimethylolpropane / hexamethylene diisocyanate trimer adduct, and isocyanurate of hexamethylene diisocyanate, such as polyether polyisocyanate and polyester Polyol adducts such as polyisocyanates, for example, isocyanurates, burettes, Such as Rofaneto body, and the like.

  As the epoxy-based cross-linking agent, preferably, a polyfunctional epoxy-based compound is exemplified. Specifically, for example, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis ( N, N-diglycidylaminomethyl) cyclohexane (trade name “Tetrad C”, manufactured by Mitsubishi Gas Chemical Company) and the like.

  The mixing ratio of the crosslinking agent is, for example, 1 part by mass or more, preferably 2 parts by mass or more, and for example, 15 parts by mass or less, preferably 5 parts by mass or less with respect to 100 parts by mass of the polymer component. is there. By adjusting the blending ratio of the crosslinking agent, the peeling force of the pressure-sensitive adhesive layer 5 can be adjusted.

  When a crosslinking agent is contained, a crosslinking catalyst is more preferably included. Examples of the crosslinking catalyst include tin catalysts such as tin octoate, dioctyltin dilaurate, dibutyltin bis (acetylacetonate), and tin-based chelate compounds, for example, iron tris (acetylacetonate), iron trimethoxy, Examples include iron-based catalysts such as propoxy iron and ferric chloride. These crosslinking catalysts can be used alone or in combination of two or more. Preferably, a tin-based catalyst is used.

  The mixing ratio of the crosslinking catalyst is, for example, 0.1 part by mass or more, preferably 0.2 part by mass or more, and for example, 5 parts by mass or less, preferably 3 parts by mass, based on 100 parts by mass of the crosslinking agent. Not more than parts by mass. By adjusting the blending ratio of the crosslinking catalyst, the peeling force of the pressure-sensitive adhesive layer 5 can be adjusted.

  The pressure-sensitive adhesive composition may further appropriately contain known additives such as a tackifier resin, a processing aid, a pigment, a flame retardant, a filler, a softener, and an antioxidant.

  The thickness of the pressure-sensitive adhesive layer 5 is, for example, 5 μm or more, preferably 10 μm or more, and is, for example, 100 μm or less, preferably 50 μm or less.

  The thickness of the pressure-sensitive adhesive layer 5 can be measured using a dial gauge (manufactured by PEACOCK, “DG-205”).

  The thickness of the carrier film 2 is, for example, 10 μm or more, preferably 20 μm or more, and is, for example, 100 μm or less, preferably 75 μm or less, more preferably 50 μm or less, and further preferably 25 μm or less. When the thickness of the carrier film 2 is equal to or less than the above upper limit, it is possible to suppress the occurrence of curling when the glass laminate 1 is heated. On the other hand, when the thickness of the carrier film 2 is equal to or more than the above lower limit, the mechanical strength is excellent, and the breakage of the glass substrate 3 can be suppressed.

3. Glass Base The glass base 3 is a support member that secures mechanical strength of an optical member such as a transparent conductive glass (described later) and supports a functional layer such as a transparent conductive layer (described below).

  The glass substrate 3 has a film shape and is arranged on the entire upper surface of the carrier film 2 so as to be in contact with the upper surface of the carrier film 2. Specifically, the glass substrate 3 is pressure-sensitively bonded to the upper surface of the pressure-sensitive adhesive layer 5.

  The glass substrate 3 has flexibility and is formed of transparent glass.

  Examples of the glass include non-alkali glass, soda glass, borosilicate glass, and aluminosilicate glass.

  The upper surface or the lower surface of the glass substrate 3 may be subjected to a known base treatment (primer treatment). That is, the glass substrate 3 may be provided with a primer layer on the upper surface or the lower surface.

  The thickness of the glass substrate 3 is 150 μm or less, preferably 120 μm or less, and more preferably 100 μm or less. Also, for example, it is 10 μm or more, preferably 50 μm or more. When the thickness of the glass substrate 3 is equal to or less than the upper limit, the glass substrate 3 has excellent flexibility and can be wound into a roll. Further, when the thickness of the glass substrate 3 is equal to or more than the above lower limit, mechanical strength is excellent, and breakage during transportation can be suppressed.

  The thickness of the glass substrate 3 can be measured using a dial gauge (manufactured by PEACOCK, “DG-205”).

4. Method for Manufacturing Glass Laminate A method for manufacturing the glass laminate 1 will be described. The method for manufacturing the glass laminate 1 includes, for example, a preparing step and a sticking step in this order. The glass laminate 1 is manufactured by, for example, a roll-to-roll method.

(Preparation process)
In the preparation step, the carrier film 2 is prepared.

  The carrier film 2 can be obtained by applying and drying a diluent obtained by diluting the pressure-sensitive adhesive composition with a solvent on the upper surface of the long plastic substrate 4.

  Examples of the solvent include an organic solvent and an aqueous solvent (specifically, water), and preferably, an organic solvent. As the organic solvent, for example, methanol, ethanol, alcohol compounds such as isopropyl alcohol, for example, acetone, methyl ethyl ketone, ketone compounds such as methyl isobutyl ketone, for example, ethyl acetate, ester compounds such as butyl acetate, propylene glycol monomethyl ether and the like Ether compounds, for example, aromatic compounds such as toluene and xylene are exemplified. These solvents can be used alone or in combination of two or more. Preferably, an ester compound is used.

  The solid content concentration in the diluent is, for example, 1% by mass or more, preferably 10% by mass or more, and for example, 40% by mass or less, preferably 30% by mass or less.

  The application method can be appropriately selected according to the application liquid and the plastic substrate 4. For example, a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, an ink jet method and the like can be mentioned.

  The drying temperature is, for example, 50 ° C or higher, preferably 100 ° C or higher, for example, 200 ° C or lower, preferably 150 ° C or lower.

  The drying time is, for example, 0.5 minutes or more, preferably 1 minute or more, and for example, 30 minutes or less, preferably 10 minutes or less.

(Adhering process)
In the attaching step, the carrier film 2 is attached to the glass substrate 3.

  Specifically, the lower surface of the long glass substrate 3 is brought into contact with the pressure-sensitive adhesive layer 5 of the carrier film 2.

  Known or commercially available glass substrates 3 can be used. The long glass substrate 3 generally includes the glass substrate 3 and spacers (such as slip sheets) disposed on one surface thereof, and these are wound in a roll shape. This spacer is removed from the glass substrate 3 before the attaching step.

  If necessary, from the viewpoint of the adhesion between the glass substrate 3 and the transparent conductive layer (described later), for example, sputtering, corona discharge, flame, ultraviolet irradiation, electron beam, Etching treatment such as irradiation, chemical conversion, and oxidation can be performed. Further, the glass substrate 3 can be dust-removed and cleaned by solvent cleaning, ultrasonic cleaning, or the like.

  Thereby, the glass laminate 1 including the carrier film 2 and the glass substrate 3 disposed on the upper surface thereof is obtained.

  The thickness of the glass laminate 1 is, for example, 50 μm or more, preferably 100 μm or more, and is, for example, 300 μm or less, preferably 200 μm or less.

  In the glass laminate 1 before heating, that is, in the initial glass laminate 1, the peeling force between the carrier film 2 and the glass substrate 3 is, for example, 0.05 N / 50 mm or more, preferably 0.1 N / 50 mm or more. It is 50 mm or more, and for example, 1.5 N / 50 mm or less, preferably 1.0 N / 50 mm or less, more preferably 0.5 N / 50 mm or less. When the peeling force is equal to or more than the lower limit, peeling and detachment between the carrier film 2 and the glass substrate 3 during transport can be suppressed. When the peeling force is equal to or less than the upper limit, when the glass laminate 1 is heated, an excessive increase in the peeling force can be suppressed, and the carrier film 2 can be smoothly removed from the glass laminate 1. it can.

  In the glass laminate 1 after heating, specifically, in the glass laminate 1 when heated at 140 ° C. for 60 minutes, the peeling force between the carrier film 2 and the glass substrate 3 is 0.1 N / 50 mm or more. 2.0 N / 50 mm or less. It is preferably at least 0.5 N / 50 mm, more preferably at least 1.0 N / 50 mm, and preferably at most 1.8 N / 50 mm. That is, when the glass laminate 1 is heated at 140 ° C. for 60 minutes, the peeling force between the carrier film 2 and the glass substrate 3 falls within the above range. When the peeling force is equal to or more than the lower limit, generation of bubbles between the carrier film 2 and the glass laminate 1 can be suppressed. Further, when the peeling force is equal to or less than the upper limit, the carrier film 2 can be smoothly removed from the glass laminate 1 and the breakage of the glass substrate 3 can be suppressed.

  These peeling forces can be measured using a sample obtained by cutting the glass laminate 1 to a width of 50 mm under the conditions of a tensile speed of 300 mm / min and a peeling angle of 180 °. More specifically, this will be described in detail in Examples.

5. Use of Glass Laminate The glass laminate 1 can be used, for example, in a method for manufacturing an optical member. Hereinafter, as one embodiment of a method for manufacturing an optical member, a method for manufacturing the transparent conductive glass 6 shown in FIG. 2 using the glass laminate 1 will be described.

  The method for manufacturing the transparent conductive glass 6 includes, for example, a conductive layer disposing step and a heating step in this order. The transparent conductive glass 6 is manufactured by, for example, a roll-to-roll method.

(Conducting layer arrangement step)
In the conductive layer disposing step, the transparent conductive layer 7 is disposed on the upper surface of the glass laminate 1.

  Specifically, for example, the transparent conductive layer 7 is formed on the upper surface of the glass substrate 3 by a dry method.

  Examples of the dry method include a vacuum deposition method, a sputtering method, and an ion plating method. Preferably, a sputtering method is used. According to this method, the transparent conductive layer 7 which is a thin film and has a uniform thickness can be formed.

  When the sputtering method is employed, as a target material, a metal oxide described later which forms the transparent conductive layer 7 and the like are mentioned, and preferably, ITO is mentioned. The tin oxide concentration of ITO is, for example, 0.5% by mass or more, preferably 3% by mass or more, and, for example, 15% by mass or less, from the viewpoints of durability and crystallization of the ITO layer. , 13% by mass or less.

  Examples of the gas include an inert gas such as Ar. If necessary, a reactive gas such as oxygen gas can be used in combination. When a reactive gas is used in combination, the flow ratio (sccm) of the reactive gas is not particularly limited, but is, for example, 0.1 to 5% by flow with respect to the total flow ratio of the sputtering gas and the reactive gas. It is.

  The air pressure during sputtering is, for example, 1 Pa or less, and preferably 0.1 Pa or more and 0.7 Pa or less, from the viewpoint of suppressing a decrease in the sputtering rate and discharging stability.

  The power source may be, for example, any of a DC power source, an AC power source, an MF power source, and an RF power source, or a combination thereof.

  Thereby, as shown in FIG. 2, a transparent conductive glass laminate 8 including the carrier film 2 and the transparent conductive glass 6 disposed on the upper surface thereof is obtained.

  At this time, the peeling force between the carrier film 2 and the transparent conductive glass 6 is substantially the same as the peeling force between the initial carrier film 2 and the glass substrate 3 described above.

(Heating process)
In the heating step, a heating step is performed on the transparent conductive glass laminate 8.

  The heat treatment can be performed using, for example, an infrared heater, an oven, or the like.

  The heating atmosphere may be either under air or under vacuum, but is preferably under air from the viewpoint of crystallization.

  The heating temperature is, for example, 100 ° C. or higher, preferably 120 ° C. or higher, and, for example, 200 ° C. or lower, preferably 160 ° C. or lower. When the heating temperature is within the above range, the crystal conversion can be ensured while suppressing the thermal damage of the plastic base material 4 and the impurities generated thereby.

  The heating time is appropriately determined according to the heating temperature, but is, for example, 10 minutes or more, preferably 30 minutes or more, and for example, 5 hours or less, preferably 2 hours or less.

  Thereby, when the transparent conductive layer 7 is made of ITO or the like, the transparent conductive layer 7 is crystallized, and the conductivity of the transparent conductive layer 7 is improved. Specifically, a transparent conductive glass laminate 8 including the glass substrate 3 and the heated transparent conductive layer 7 disposed on the upper surface thereof is obtained.

  The peeling force between the carrier film 2 and the transparent conductive glass 6 in the transparent conductive glass laminate 8 after heating is the same as the peeling force between the carrier film 2 and the glass substrate 3 in the heated glass laminate 1 described above. Substantially the same.

  Next, it is wound into a roll. Thereby, the long transparent conductive glass laminate 8 is obtained as a roll body 9 wound in a roll shape as shown in FIG.

  If necessary, the transparent conductive layer 7 is then patterned by known etching. The etching may be performed before winding the transparent conductive glass laminate 8 as a roll body 9. Alternatively, after the transparent conductive glass laminate 8 is fed out from the roll body 9 by a roll-to-roll method, etching may be performed, and the roll may be wound again in a roll shape.

  The pattern of the transparent conductive layer 7 is appropriately determined according to the application to which the transparent conductive glass 6 is applied, and examples thereof include an electrode pattern and a wiring pattern having a stripe shape or the like.

6. Transparent conductive glass laminate The transparent conductive glass laminate 8 includes the carrier film 2 and the transparent conductive glass 6 disposed on the upper surface thereof. The transparent conductive glass 6 includes a glass substrate 3 and a transparent conductive layer 7 disposed on the upper surface thereof. In other words, the transparent conductive glass laminate 8 includes the glass laminate 1 and the transparent conductive layer 7 disposed on the upper surface thereof.

(Transparent conductive layer)
The transparent conductive layer 7 is a conductive layer for forming a desired transparent pattern such as an electrode pattern and a wiring pattern.

  The transparent conductive layer 7 is the uppermost layer of the transparent conductive glass laminate 8 and has a film shape. The transparent conductive layer 7 is disposed on the entire upper surface of the glass substrate 3 so as to contact the upper surface of the glass substrate 3.

  As the material of the transparent conductive layer 7, for example, at least one selected from the group consisting of In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, and W And metal oxides containing the above metals. The metal oxide may be further doped with a metal atom shown in the above group, if necessary.

  Specific examples of the transparent conductive layer 7 include indium-containing oxides such as indium tin composite oxide (ITO), and antimony-containing oxides such as antimony tin composite oxide (ATO). Preferably, an indium-containing oxide, more preferably, ITO is used.

When the transparent conductive layer 7 is made of ITO, the content of tin oxide (SnO ₂ ) is, for example, 0.5% by mass or more, preferably, based on the total amount of tin oxide and indium oxide (In ₂ O ₃ ). It is at least 3% by mass, and for example, at most 15% by mass, preferably at most 13% by mass. When the content of tin oxide is at least the lower limit, the durability of the transparent conductive layer 7 can be further improved. In addition, when the content of tin oxide is equal to or less than the above upper limit, the crystal conversion of the transparent conductive layer 7 can be easily performed, and the stability of transparency and specific resistance can be improved.

  “ITO” in the present specification may be any composite oxide containing at least indium (In) and tin (Sn), and may contain additional components other than these. Examples of the additional component include metal elements other than In and Sn. Specifically, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, W, Fe , Pb, Ni, Nb, Cr, Ga and the like.

The specific resistance of the transparent conductive layer 7 is, for example, 5.0 × 10 ⁻⁴ Ω · cm or less, and preferably 2.0 × 10 ⁻⁴ Ω · cm or less. The specific resistance can be measured by a four-terminal method.

  The thickness of the transparent conductive layer 7 is, for example, 10 nm or more, preferably 30 nm or more, and is, for example, 300 nm or less, preferably 100 nm or less. When the thickness of the transparent conductive layer 7 is equal to or more than the lower limit, the conductivity is excellent. On the other hand, when the thickness of the transparent conductive layer 7 is equal to or less than the above upper limit, the thickness of the transparent conductive glass 6 can be reduced. The thickness of the transparent conductive layer 7 can be measured using a scanning X-ray fluorescence analyzer.

  The transparent conductive layer 7 may be amorphous or crystalline, but is preferably crystalline when a heating step is performed. If the transparent conductive layer 7 is crystalline, it has excellent conductivity.

  Whether the transparent conductive layer is amorphous or crystalline is determined, for example, when the transparent conductive layer is an ITO layer, immersed in hydrochloric acid (concentration: 5% by mass) at 20 ° C. for 15 minutes, washed with water and dried, and dried to about 15 mm. It can be determined by measuring the inter-terminal resistance between the two. In the present specification, when the resistance between terminals between 15 mm exceeds 10 kΩ after immersion in hydrochloric acid (20 ° C., concentration 5% by mass), washing with water and drying, the ITO layer is made amorphous and the terminal between 15 mm When the inter-resistance is 10 kΩ or less, the ITO layer is crystalline.

  The transparent conductive glass laminate 8 is used for an optical device such as an image display device, for example. More specifically, the carrier film 2 is removed (peeled) from the transparent conductive glass laminate 8, and the transparent conductive glass 6 is used as a member of an image display device.

  Specifically, when the transparent conductive glass 6 is provided in an image display device (for example, an image display device having an image display element such as an LCD module or an organic EL module), the transparent conductive glass 6 may be, for example, a touch panel. Used as a base material. Examples of the type of the touch panel include various types such as an optical type, an ultrasonic type, a capacitance type, and a resistance film type, and are particularly suitably used for a capacitance type touch panel.

  The transparent conductive glass 6 is a component such as a base material for a touch panel provided in an image display device, for example, and is not an image display device. That is, the transparent conductive glass 6 is a component for producing an image display device or the like, does not include an image display element such as an LCD module, includes the glass base material 3 and the transparent conductive layer 7, and is distributed as a component alone. And it is a device that can be used industrially.

  Since the glass laminate 1 and the transparent conductive glass laminate 8 include the carrier film 2 and the glass substrate 3 having a thickness of 150 μm or less, the glass laminate 1 and the transparent conductive glass laminate 8 can be formed into a roll body 9 by a roll-to-roll method. Industrial production is possible.

  Further, since the carrier film 2 includes the plastic base material 4 having a thickness of 100 μm or less and the pressure-sensitive adhesive layer 5, the glass base material laminated on the roll body 9 at the time of winding by the roll-to-roll method. The stress between the members 3 can be reduced, and breakage due to the stress can be suppressed.

  Further, since the carrier film 2 includes the plastic substrate 4 having a thickness of 100 μm or less and the pressure-sensitive adhesive layer 5, the heat shrinkage of the plastic substrate 4 can be reduced, and curling after heating can be suppressed. . Therefore, the glass laminate 1 after heating can be easily rolled.

  Further, when the glass laminate 1 or the transparent conductive glass laminate 8 is heated at 140 ° C. for 60 minutes, the peeling force between the carrier film 2 and the glass substrate 3 (therefore, the transparent conductive glass 6) is 0.1 N. Since it is not less than / 50 mm and not more than 2.0 N / 50 mm, the carrier film 2 can be smoothly separated from the glass substrate 3 (or the transparent conductive glass 6) even after heating. Therefore, when the carrier film 2 is peeled, the breakage of the glass substrate 3 can be suppressed.

  In particular, the present invention has achieved mass production of an optical member (for example, transparent conductive glass 6) using the flexible glass substrate 3 as a supporting substrate by a roll-to-roll method.

  Specifically, when an optical film is manufactured by a roll-to-roll method using the flexible glass substrate 3, the glass substrate 3 is stressed by the stress between the glass substrates 3 stacked on each other in the roll-shaped optical film. The substrate 3 is damaged.

  Therefore, when the carrier film 2 is disposed on the lower surface of the glass substrate 3 in order to suppress the breakage of the glass substrate 3, due to the difference in the coefficient of thermal expansion between the carrier film 2 and the glass substrate 3 during heating, Significant curl occurs, and as a result, it is difficult to wind the film into a roll.

  Therefore, if the thickness of the plastic substrate 4 of the carrier film 2 is set to 100 μm or less in order to suppress curling, the glass substrate 3 may be damaged because the carrier film 2 cannot be smoothly separated from the glass substrate 3. There was found. Further studies on this point have revealed that the peeling force of the pressure-sensitive adhesive layer 5 increases significantly as the thickness of the plastic substrate 4 decreases.

  Based on this finding, the present inventors focused on the peeling force of the pressure-sensitive adhesive layer 5 after heating, and as a result, in addition to the configuration of the carrier film, the carrier film 2 and the glass substrate 3 after further heating. The above problem has been solved by setting the peeling force within a predetermined range. That is, the occurrence of curl due to heating, the breakage of the glass substrate 3 during winding, and the breakage of the glass substrate 3 during peeling of the carrier film were solved. For this reason, realistic mass production by the roll-to-roll system is possible.

<Modification>
Hereinafter, a modified example of the embodiment shown in FIGS. 1 and 2 will be described. Note that these modified examples also have the same operational effects as the above-described embodiment.

  (1) In FIGS. 1 and 2, as a use of the glass laminate 1, a method of manufacturing the transparent conductive glass laminate 8 is illustrated, but, for example, although not illustrated, as a use of the glass laminate 1, A method for producing an antireflection glass laminate can be exemplified.

  The anti-reflection glass laminate includes a carrier film 2 and an anti-reflection glass disposed on an upper surface thereof. The anti-reflection glass includes a glass substrate 3 and an anti-reflection layer disposed on the upper surface thereof. That is, the antireflection glass and the antireflection glass laminate include an antireflection layer instead of the transparent conductive layer 7.

  The antireflection layer includes a low-refractive-index layer and a high-refractive-index layer, and is preferably an alternate laminate of a low-refractive-index layer and a high-refractive-index layer.

  The refractive index of the low refractive layer is, for example, 1.35 or more and 1.55 or less. Examples of the material for the low refractive layer include silicon oxide and magnesium fluoride.

  The refractive index of the high refractive index layer is, for example, 1.80 or more and 2.40 or less. Examples of the material of the high refractive layer include titanium oxide, niobium oxide, zirconium oxide, ITO, and ATO.

  The total thickness of the antireflection layer is, for example, 100 nm or more, preferably 200 nm or more, and is, for example, 500 nm or less, preferably 300 nm or less.

  Such an antireflection layer is described in, for example, JP-A-2017-227898.

  The antireflection glass laminate can be manufactured by performing the antireflection layer disposing step instead of the conductive layer disposing step in the method for producing the transparent conductive glass laminate 8.

  In the antireflection layer disposing step, an antireflection layer is formed on the upper surface of the glass substrate 3 by a dry method. Examples of the dry method include those described above, and preferably include a sputtering method.

  In the case where the sputtering method is adopted, a material constituting the above-described antireflection layer is used as a target material. That is, a target made of the material of the high refractive layer and a target made of the material of the low refractive layer are used.

  (2) As a use of the glass laminate 1, for example, although not shown, a functional layer other than the transparent conductive layer 7 and the antireflection layer is disposed on the glass substrate 3 of the glass laminate 1, and a desired functional layer ( For example, a glass laminate having an optical adjustment layer) can be manufactured.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. In addition, this invention is not limited to an Example and a comparative example at all. Specific numerical values such as the mixing ratio (content ratio), physical property values, and parameters used in the following description are the mixing ratios (corresponding to them) described in the above-mentioned “Embodiments of the Invention”. Substitute the upper limit value (value defined as “less than” or “less than”) or the lower limit value (value defined as “over” or “exceed”) such as content ratio, physical property value, and parameter be able to.

Example 1
(Preparation of carrier film)
96.2 parts by mass of 2-ethylhexyl acrylate (2EHA) and 3.8 parts by mass of hydroxyethyl acrylate (HEA) as monomer components, and 2,2′-azobisisobutyronitrile (AIBN) as a polymerization initiator 0.2 parts by mass was mixed with 150 parts by mass of ethyl acetate, and nitrogen replacement was carried out by introducing nitrogen gas while stirring at 23 ° C. Thereafter, the polymerization reaction was carried out for 6 hours while maintaining the liquid temperature at around 65 ° C., to prepare a solution of acrylic polymer A (concentration 40% by mass). The weight average molecular weight of Acrypolymer A was 540,000.

  Ethyl acetate was added to the acrylic polymer A solution to dilute it to a concentration of 20% by mass. 500 parts by mass of diluent (100 parts by mass of solid content), 4 parts by mass of toluene diisocyanate (manufactured by Tosoh, "Coronate L" (C / L)) as a crosslinking agent, and 0.02 parts by mass of dibutyltin dilaurate as a crosslinking catalyst Was added and stirred to prepare an acrylic pressure-sensitive adhesive solution.

  An acrylic pressure-sensitive adhesive solution is applied to one surface of a long polyester film (plastic substrate, manufactured by Toray Industries, Inc., “Polyester Film Lumirror 25R75”, thickness 25 μm) by a roll-to-roll method, and is heated at 130 ° C. for 2 minutes. By heating, an adhesive layer having a thickness of 23 μm was formed. Thus, a carrier film was produced.

(Manufacture of glass laminate)
A long glass substrate (100 μm thick, “G-Leaf” manufactured by NEC Corporation) was prepared. The adhesive layer of the carrier film and the glass substrate were bonded together by a roll-to-roll method, and wound around a take-up roll.

  In this way, a glass laminate provided with the carrier film and the glass substrate and wound into a roll was manufactured.

Examples 2-3
A glass laminate was produced in the same manner as in Example 1 except that the thickness of the polyester film was changed to the thickness shown in Table 1.

Example 4
In preparing the acrylic pressure-sensitive adhesive solution, 4 parts by mass of an isocyanate-based crosslinking agent “Coronate HX” (C-HX) was used as a crosslinking agent, and the amount of dibutyltin dilaurate was changed to 0.015 part by mass. Further, the thicknesses of the polyester film and the pressure-sensitive adhesive layer were changed to the thicknesses described in Example 1. Except for these, a glass laminate was manufactured in the same manner as in Example 1.

Example 5
90 parts by mass of butyl acrylate (BA) and 10 parts by mass of acrylic acid (AA) as monomer components, and 0.2 parts by mass of AIBN as a polymerization initiator were mixed with 186 parts by mass of ethyl acetate, and stirred at 23 ° C. Nitrogen gas was introduced while performing nitrogen substitution. Thereafter, the polymerization reaction was carried out for 10 hours while maintaining the liquid temperature at around 63 ° C. to prepare a solution of acrylic polymer B (concentration: 35% by mass). The weight average molecular weight of Acrypolymer B was 500,000.

  Ethyl acetate was added to the acrylic polymer B solution to dilute it to a concentration of 20% by mass. To a diluent 500 parts by mass (solid content 100 parts by mass), 11 parts by mass of a tetrafunctional epoxy compound (manufactured by Mitsubishi Gas Chemical Co., Ltd., "Tetrad C" (TC)) as a cross-linking agent was added, and the mixture was stirred. An adhesive solution was prepared.

  An acrylic pressure-sensitive adhesive solution was applied to one surface of a long polyester film (same as above) by a roll-to-roll method, and heated at 130 ° C. for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 20 μm. . Thus, a carrier film was produced.

  A glass laminate was manufactured in the same manner as in Example 1 except that this carrier film was used.

Comparative Example 1
A glass laminate was produced in the same manner as in Example 5, except that the thickness of the polyester film was changed to the thickness shown in Table 1.

Comparative Example 2
A glass laminate was produced in the same manner as in Example 5, except that the amount of the crosslinking agent in the pressure-sensitive adhesive layer was changed to the amount shown in Table 1.

Comparative Example 3
A glass laminate was produced in the same manner as in Comparative Example 2, except that the thickness of the polyester film was changed to the thickness shown in Table 1.

Comparative Example 4
A glass laminate was produced in the same manner as in Example 5, except that the amount of the crosslinking agent in the pressure-sensitive adhesive layer was changed to the amount shown in Table 1.

Comparative Example 5
A glass laminate was produced in the same manner as in Comparative Example 4, except that the thickness of the polyester film was changed to the thickness shown in Table 1.

Comparative Example 6
In the pressure-sensitive adhesive layer, the amount of the monomer component and the amount of the crosslinking agent were changed to the amounts shown in Table 1. Further, the thicknesses of the polyester film and the pressure-sensitive adhesive layer were changed to the amounts shown in Table 1. Except for these, a glass laminate was manufactured in the same manner as in Example 5.

(Thickness of each layer)
The thicknesses of the plastic film, the pressure-sensitive adhesive layer, and the glass substrate were measured using a dial gauge (“DG-205” manufactured by PEACOCK).

(Initial peeling force)
The glass laminate is cut into a width of 50 mm and a length of 200 mm, and the glass substrate 3 side of the cut glass laminate is placed on a sample table 11 of a peeling force measuring device ("TCM-1kNB" manufactured by MinebeaMitsumi). Then, it was fixed via an adhesive tape (fixing member) 12. Subsequently, one end in the length direction of the carrier film 2 in the glass laminate is gripped by the movable stage 13 and pulled in the length direction at a pulling speed of 300 mm / min, whereby the peeling force (N / 50 mm) (see FIG. 4). Table 1 shows the results.

(Peeling force after heating)
The glass laminate was heated at 140 ° C. for 60 minutes. The peel strength (N / 50 mm) at a peel angle of 180 ° was measured for the heated glass laminate under the conditions of a tensile speed of 300 mm / min in the same manner as in the test of the initial peel force. Table 1 shows the results.

(Curl test)
A test piece was prepared by cutting the glass laminate of each example and each comparative example into a 20 cm × 20 cm square shape in plan view. The test piece was placed on a horizontal table in an oven with the polyester film facing upward and heated at 140 ° C. for 60 minutes. Then, it was left to cool at room temperature (23 ° C.) for 1 hour, and this was used as a test piece after heating.

  In the test piece after heating, the average H of the heights of the four corners from the horizontal table was measured (see FIG. 5). Table 1 shows the results.

(Releasability)
With the above-mentioned peeling force after heating, the glass substrate after peeling was confirmed.

  The case where no damage was confirmed in the glass substrate was evaluated as Δ, and the case where damage such as chipping was confirmed in a part of the glass substrate was evaluated as x. Table 1 shows the results.

(Confirmation of air bubbles)
The test piece after heating in the curl test was visually observed.

  The case where no air bubbles were observed in the pressure-sensitive adhesive layer was evaluated as Δ, and the case where air bubbles were observed was evaluated as x. Table 1 shows the results.

DESCRIPTION OF SYMBOLS 1 Glass laminated body 2 Carrier film 3 Glass base material 4 Plastic base material 5 Adhesive layer 7 Transparent conductive layer

Claims (3)

A carrier film,
A glass laminate comprising a glass substrate, which is disposed on one side in the thickness direction of the carrier film and has a thickness of 150 μm or less,
The carrier film,
A plastic substrate having a thickness of 100 μm or less;
An adhesive layer disposed on one side in the thickness direction of the plastic base material,
A glass characterized in that, when the glass laminate is heated at 140 ° C. for 60 minutes, a peeling force between the carrier film and the glass substrate is 0.1 N / 50 mm or more and 2.0 N / 50 mm or less. Laminate.   The glass laminate according to claim 1, further comprising a transparent conductive layer disposed on one side in a thickness direction of the glass substrate.   The glass laminate according to claim 1, wherein the glass laminate is wound in a roll shape.

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