JP6746920B2 - Flexible electronic device manufacturing method - Google Patents

Description

The present invention, a flexible polymer film is temporarily fixed to a rigid inorganic substrate for temporary support to form a laminate, and then various electronic devices are formed on the polymer film, and then the polymer film is peeled together with the electronic device part. And a manufacturing technique for obtaining a flexible electronic device.

Functional elements (devices) such as semiconductor elements, MEMS elements, and display elements are used as electronic components in information communication devices (broadcasting devices, mobile radio, mobile communication devices, etc.), radars, high-speed information processing devices, etc. Conventionally, it was generally formed or mounted on an inorganic substrate such as glass, a silicon wafer, or a ceramic substrate. However, in recent years, with the demand for lighter weight, smaller size/thinner, and flexibility of electronic parts, attempts have been made to form various functional elements on a polymer film.

When forming various functional elements on the surface of the polymer film, it is ideal to perform processing by a so-called roll-to-roll process, which utilizes the flexibility which is a characteristic of the polymer film. However, in the industries such as the semiconductor industry, the MEMS industry, and the display industry, process technology for a rigid flat substrate such as a wafer base or a glass substrate base has been the mainstream. Therefore, in order to form various functional elements on the surface of the polymer film by utilizing the existing infrastructure, the polymer solution or polymer is applied to the rigid support made of an inorganic material (glass plate, ceramic plate, silicon wafer, metal plate, etc.). The precursor solution is applied and dried to form a film, on which the desired element is formed and then peeled from the support, or the film is temporarily fixed to a support made of an inorganic material, and the desired element is formed into a film. A process of peeling from the support after being formed has been developed (Patent Documents 1 to 3).

Generally, a relatively high temperature is often used in the process of forming the functional element. For example, a temperature range of about 120 to 500° C. is used in forming a functional element such as polysilicon or an oxide semiconductor. In manufacturing a low temperature polysilicon thin film transistor, heating at about 450° C. may be necessary for dehydrogenation. A temperature range of about 150 to 250° C. is required also for manufacturing a hydrogenated amorphous silicon thin film. Although the temperature range illustrated here is not so high for an inorganic material, it must be said that it is a considerably high temperature for a polymer film and an adhesive generally used for bonding polymer films. I don't get it. In the method of bonding the polymer film to the inorganic substrate described above and peeling it after forming the functional element, the polymer film used and the adhesive and pressure-sensitive adhesive used for bonding also require sufficient heat resistance. However, as a practical matter, the polymer films that can practically withstand such high temperature range are limited. In addition, there are very few conventional adhesives and pressure-sensitive adhesives for bonding which have sufficient heat resistance.

A polymer film or a precursor solution is applied to a support made of an inorganic material as mentioned above to form a film by drying, and a desired element is formed on the support, followed by peeling from the support. This is a technology developed because a heat-resistant adhesive means for temporarily adhering a substrate to an inorganic substrate cannot be obtained. However, since the polymer film obtained by such means is intimately adhered to the inorganic substrate, even if it is peeled from the inorganic substrate, it is fragile and easily cracked, so that the functional element is destroyed when peeled from the inorganic substrate. It often happens. In particular, peeling a device having a large area is extremely difficult and the productivity is not sufficient.

In view of such circumstances, the present inventors form a laminate of a polymer film and a support for forming a functional element, a polyimide film having excellent heat resistance and toughness and capable of being thinned, It has been proposed a laminated body which is bonded to a support (inorganic layer) made of an inorganic material via a coupling agent (Patent Documents 4 to 6).

Since the polymer film is originally a flexible material, it does not interfere with stretching and bending. On the other hand, electronic devices formed on polymer films often have a fine structure in which conductors and semiconductors made of inorganic substances are combined in a predetermined pattern, and stress due to minute expansion and contraction or bending and stretching. As a result, the fine structure is destroyed and the device characteristics are impaired. Such stress is likely to occur when the electronic device, together with the polymer film, is separated from the inorganic substrate.
Therefore, the inventors of the present invention have made further improvements to partially inactivate the coupling agent-treated inorganic substrate to form a high activity portion and a low activity portion of the coupling agent. When a molecular film is attached, a good adhesive part that is relatively difficult to peel off and an easy peeling part that is relatively easy to peel off are formed, and an electronic device is formed on the easy peeling part. A technique has been proposed in which a cut is made at the boundary with the adhesive portion and only the easily peelable portion is peeled off, whereby peeling can be performed in a state in which stress applied to the electronic device is reduced (Patent Document 7).

JP-A-58-91446 JP, 10-125930, A Japanese Patent Laid-Open No. 2000-243943 JP, 2010-283262, A JP, 2011-11455, A JP, 2011-245675, A JP, 2013-010342, A

According to the laminates described in Patent Documents 4 to 7 described above, the polymer film and the inorganic substrate can be bonded to each other without using a so-called adhesive or pressure-sensitive adhesive, and further, the laminate forms a thin film device. The polymer film does not peel when exposed to the high temperatures required to do so. Therefore, it becomes possible to subject the laminate to a conventional process for directly forming an electronic device on an inorganic substrate such as a glass plate or a silicon wafer. However, in such a technique, a vacuum plasma treatment is often used for the activation treatment of the film, and thus there are problems in productivity and processing cost. The wet treatment is advantageous in terms of cost, but in some polymer films, the alkaline component used in the wet treatment deteriorates the film itself and lowers the mechanical strength, and the adhesive strength with the support. Could become unstable, and problems such as the film falling off during the process could occur.

In this way, a method of manufacturing a flexible electronic device by temporarily fixing a polymer film to a support substrate made of an inorganic material (hereinafter referred to as an inorganic substrate) to perform device processing and peeling the polymer film from the inorganic substrate is Since the vacuum device is used during the surface activation treatment of the polymer film and the heating and pressing of the polymer film and the inorganic substrate, the productivity and processing cost are not sufficient, and the surface activation treatment and the heating and pressurization without using the vacuum device are performed. The establishment of a method was desired.
Therefore, the present invention does not require the use of a vacuum device during the surface activation treatment of the polymer film or the heating and pressing of the polymer film and the inorganic substrate, and the laminate of the polymer film and the inorganic substrate is stably bonded. In addition to the above, it is an object to provide a method capable of easily peeling a polymer film from an inorganic substrate after mounting an electronic device.

In order to solve such a problem, the inventors of the present invention have made intensive studies, particularly as a result of a wet treatment, and have found a treatment liquid that enables extremely stable bonding (temporary support), and completed the present invention.

That is, the present invention has the following configurations.
[1] In a method for producing a flexible electronic device, which comprises bonding a polymer film to an inorganic substrate, forming an electronic device on the polymer film, and then peeling the polymer film from the inorganic substrate, bonding the polymer film to at least the inorganic substrate. A method for producing a flexible electronic device, wherein the surface of the polymer film is surface-activated by an alkaline solution containing oxyalkylamine.
[2] The method for producing a flexible electronic device according to [1], wherein the oxyalkylamine is one or more selected from the group consisting of monooxymonoamine and monoaminopolyhydric alcohol.
[3] The method for producing a flexible electronic device according to [1] or [2], wherein the polymer film is a condensation polymer film.
[4] The method for producing a flexible electronic device according to any one of [1] to [3], wherein the polymer film is a polyimide film, a polyethylene naphthalate film or a liquid crystal polymer film.
[5] Bonding of the inorganic substrate and the polymer film is performed by heating and pressurizing the surface-activated inorganic substrate and the surface-activated polymer film [1] to [4]. ] The manufacturing method of the flexible electronic device in any one of.
[6] The method for manufacturing a flexible electronic device according to any one of [1] to [5], wherein the surface of the inorganic substrate to be bonded to the polymer film is treated with a silane coupling agent.

According to the present invention, it is not necessary to use a vacuum device at the time of surface activation treatment of a polymer film or at the time of heating and pressurizing a polymer film and an inorganic substrate, and a laminate of the polymer film and the inorganic substrate is stably bonded. In addition, the polymer film can be easily peeled from the inorganic substrate after mounting the electronic device.

In the present invention, a surface activated polymer film using an alkaline solution containing oxyalkylamine and an inorganic substrate such as glass, ceramics or a metal plate are laminated to form a laminate, and a device is formed on the film. After that, the polymer film can be peeled off to obtain a flexible device. It is considered that the adhesion between the polymer film and the inorganic substrate is due to a chemical reaction or a hydrogen bond between the functional group on the film surface and the polar component or functional group on the inorganic substrate surface.

In the present invention, an alkaline solution containing an oxyalkylamine is considered to generate a functional group involved in adhesion on the surface of the polymer film, and particularly in the case of a condensation-type polymer film, a suitable adhesive property is expressed. Conceivable. Also in the case of a vinyl polymer, the adhesive effect can be obtained even when the side chain has a condensation reaction group such as an ester bond, an amide bond or an imide bond.

Due to such effects, the polymer film bonded to the inorganic substrate does not peel off even when exposed to conditions such as heating, depressurization, alkali treatment, acid treatment, and washing with an organic solvent at the time of device formation, and the device formation does not occur. It is possible.

The polymer film can be peeled off after the device is formed by means such as laser irradiation from the back surface of the inorganic substrate, flash lamp irradiation, or the like. Also, by strongly adhering the area around the polymer film pasting surface and keeping the adhesive force weak in the device formation area near the center of the polymer film, the boundary between the strong adhesion portion and the weak adhesion portion is cut after device formation. Then, only the device formation region can be peeled off. The strength of the adhesive force can be realized by patterning the inorganic substrate side or the polymer film side.

The method for producing a flexible electronic device of the present invention is a method for producing a flexible electronic device, which comprises bonding a polymer film to an inorganic substrate, forming an electronic device on the polymer film, and then peeling the polymer film from the inorganic substrate. In the above, at least the surface of the polymer film to be bonded to the inorganic substrate is surface-activated with an alkaline solution containing oxyalkylamine.

<Inorganic substrate>
In the present invention, an inorganic substrate is used as a support for the polymer film. The inorganic substrate may be a plate-shaped substrate that can be used as a substrate made of an inorganic material, and examples thereof include those mainly containing glass, ceramics, semiconductor wafers, metals, and the like, glass, ceramics, semiconductor wafers, and metals. Examples of the composite of include those in which these are laminated, those in which these are dispersed, and those in which these fibers are contained.

Examples of the glass include quartz glass, high silicate glass (96% silica), soda lime glass, lead glass, aluminoborosilicate glass, borosilicate glass (Pyrex (registered trademark)), borosilicate glass (non-alkali), and borosilicate. Acid glass (microsheet), aluminosilicate glass, etc. are included. Among these, those having a linear expansion coefficient of 5 ppm/° C. or less are desirable, and if they are commercially available products, “Corning (registered trademark) 7059” and “Corning (registered trademark) 1737” manufactured by Corning Corporation, which are glass for liquid crystal, “EAGLE”, “AN100” manufactured by Asahi Glass Co., Ltd., “OA10” manufactured by Nippon Electric Glass Co., Ltd., “AF32” manufactured by SCHOTT, etc. are preferable.

As the _{ceramic, Al 2 O 3, Mullite,} AlN, SiC, Si 3 N 4, BN, crystallized glass, Cordierite, Spodumene, Pb-BSG + CaZrO 3 + Al 2 O 3, Crystallized glass + Al 2 O 3, Crystallized Ca-BSG, BSG + Quartz, BSG + Quartz, BSG + Al 2 O 3, Pb + BSG + Al 2 O 3, Glass-ceramic, ceramic substrate such as Zerodur material, TiO _2, strontium titanate, calcium titanate, magnesium titanate, alumina, MgO, steer _{tight, BaTi 4 O 9, BaTiO 3} , BaTi 4 + CaZrO 3, BaSrCaZrTiO 3, Ba (TiZr) O 3, capacitor materials such as PMN-PT or _{PFN-PFW, PbNb 2 O 6} , Pb 0.5 Be 0.5 Nb 2 O 6 , PbTiO ₃ , BaTiO ₃ , PZT, 0.855PZT-95PT-0.5BT, 0.873PZT-0.97PT-0.3BT, PLZT and the like.

A silicon wafer, a semiconductor wafer, a compound semiconductor wafer, or the like can be used as the semiconductor wafer. The silicon wafer is, for example, a product obtained by processing a single crystal or polycrystal silicon on a thin plate, and may include an n-type or p-type doped silicon wafer, an intrinsic silicon wafer, and the like. Further, a silicon wafer in which a silicon oxide layer or various thin films are deposited on the surface of the silicon wafer may be included.
In addition to silicon wafers, germanium, silicon-germanium, gallium-arsenic, aluminum-gallium-indium, nitrogen-phosphorus-arsenic-antimony, SiC, InP (indium phosphide), InGaAs, GaInNAs, LT, LN, ZnO (zinc oxide). A semiconductor wafer of CdTe (cadmium tellurium), ZnSe (zinc selenide), a compound semiconductor wafer, or the like can be used.

Examples of the metal include single element metals such as W, Mo, Pt, Fe, Ni and Au, alloys such as Inconel, Monel, mnemonic, carbon copper, Fe—Ni based Invar alloy and Super Invar alloy. In addition, a multi-layer metal obtained by adding another metal layer or a ceramic layer to these metals is also included. In this case, if the total CTE with the additional layer is low, Cu, Al, etc. are also used for the main metal layer. The metal used as the additional metal layer is not limited as long as it has strong adhesion to the polyimide film, does not diffuse, and has properties such as good chemical resistance and heat resistance. Suitable examples include chromium, nickel, TiN, and Mo-containing Cu.

It is desirable that the flat surface portion of the inorganic substrate is sufficiently flat. Specifically, the surface roughness Ra is, for example, 10 nm or less, preferably 3 nm or less, and more preferably 0.9 nm or less. The PV value of the surface roughness is, for example, 50 nm or less, preferably 20 nm or less, more preferably 5 nm or less. If it is rougher than this, the adhesive strength between the polymer film and the inorganic substrate may be insufficient.
The thickness of the inorganic substrate is not particularly limited, but from the viewpoint of handleability, the thickness is preferably 10 mm or less, more preferably 3 mm or less, and further preferably 1.3 mm or less. The lower limit of the thickness is not particularly limited, but is, for example, 0.07 mm or more, preferably 0.15 mm or more, more preferably 0.3 mm or more.

The inorganic substrate in the present invention preferably has a size of at least 4900 cm ² or more. The inorganic substrate of the present invention preferably has a substantially rectangular shape with at least 700 mm on the short side. Area of preferred inorganic substrate in the present invention is 5000 cm ² or more, more preferably 10000 cm ² or more, even more preferably 18000Cm ² or more. The length of the short side of the rectangle of the inorganic substrate in the present invention is more preferably 730 mm or more, further preferably 840 mm or more, and even more preferably 1000 mm or more.

The term “substantially rectangular” means that the corners R, cutouts, notches, orientation flats, etc. of the rectangle are allowed. For example, in the flat panel display industry according to the present invention, a 680×880 mm to 730×920 mm glass substrate called the 4th generation, a 1000×1200 mm to 1100×1250 mm to 1300×1500 mm glass substrate called the 5th generation, 1370x1670mm to 1500x1800mm glass substrate called 6th generation, 1870x2200mm glass substrate called 7th generation, 2160x2460mm to 2200x2500mm glass substrate called 8th generation, 2400x called 9th generation A 2800 mm glass substrate, a 2880×3130 mm glass substrate called the 10th generation, a 3320×3000 mm glass substrate called the 11th generation, or a glass substrate having a size larger than that corresponds to this “substantially rectangular shape”. However, the present invention is not limited to application to an inorganic substrate having a size smaller than the area, size, and short side length of a rectangle illustrated here.

In the present invention, an ultrathin glass sheet or roll having a thickness of, for example, 200 μm or less, preferably 110 μm or less, more preferably 55 μm or less, still more preferably 33 μm or less may be used as the inorganic substrate.

<Polymer film>
As the polymer film in the present invention, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, wholly aromatic polyester, other copolyester, polymethylmethacrylate, other copolyester acrylate, polycarbonate, polyamide, poly Sulfone, polyether sulfone, polyether ketone, polyamideimide, polyetherimide, aromatic polyimide, alicyclic polyimide, fluorinated polyimide, cellulose acetate, cellulose nitrate, aromatic polyamide, polyvinyl chloride, polyphenol, polyarylate, polyphenylene Films of sulfide, polyphenylene oxide, polystyrene, liquid crystal polymer, etc. can be used.
In the present invention, among these polymer films, a polymer film obtained by a condensation polymerization reaction (condensation-type polymer film) is preferable. In the present invention, a polymer having a heat resistance of 100° C. or higher, that is, a so-called engineering plastic film is particularly effective and useful. Here, the heat resistance means the property that the glass transition temperature or the heat distortion temperature is 100° C. or higher. The polycondensation polymer film (condensation-type polymer film) preferably used in the present invention is a polyester film, a polyamide film, a polyamideimide film, a polyimide film, a polybenzazole film, a polyimidebenzazole film, a polyethylene naphthalate film, a liquid crystal polymer. A film, more preferably a polyimide film, a polyethylene naphthalate film or a liquid crystal polymer film.

The Young's modulus (tensile elastic modulus) of the polymer film of the present invention is preferably 2 GPa or more, more preferably 3.5 GPa or more, further preferably 6 GPa or more, even more preferably 7.4 GPa or more, and particularly preferably 8 0.2 GPa or more, most preferably 9.1 GPa or more. Young's modulus is the Young's modulus obtained by pulling. If the Young's modulus is less than this range, the elongation of the polymer film becomes large when the polymer film is peeled from the inorganic substrate, and the electronic device is likely to be broken.
In the present invention, the upper limit of the Young's modulus is not particularly limited, but is actually about 15 GPa. A material having a too high Young's modulus is not suitable as a base material for a flexible electronic device because the film is often brittle and easily broken.

The lower limit of the thickness of the polymer film of the present invention is not particularly limited, but 4.5 μm or more is preferable in order to maintain the minimum mechanical strength as a base material of an electronic device. In the present invention, the thickness of the polymer film is more preferably 12 μm or more, further preferably 24 μm or more, still more preferably 45 μm or more. The upper limit of the thickness of the polymer film is not particularly limited, but as a flexible electronic device, it is preferably 250 μm or less, more preferably 150 μm or less, and further preferably 90 μm or less.

The polymer film particularly preferably used in the present invention is a polyimide film, and aromatic polyimide, alicyclic polyimide, polyamideimide, polyetherimide or the like can be used. When the present invention is particularly used for manufacturing a flexible display element, it is preferable to use a polyimide resin film having a colorless transparency, but particularly in the case of forming a rear element of a reflective or self-luminous display, Not limited to this.

In general, a polyimide film is obtained by applying a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent onto a support for polyimide film production, and drying the green film (“precursor film”). Or "polyamic acid film"), and is further obtained by subjecting the green film to high-temperature heat treatment on a support for producing a polyimide film or in a state of being peeled from the support to carry out a dehydration ring-closing reaction.

The diamines that compose the polyamic acid are not particularly limited, and aromatic diamines, aliphatic diamines, alicyclic diamines and the like that are commonly used in polyimide synthesis can be used. From the viewpoint of heat resistance, aromatic diamines are preferable, and among the aromatic diamines, aromatic diamines having a benzoxazole structure are more preferable. When aromatic diamines having a benzoxazole structure are used, high heat resistance, high elastic modulus, low heat shrinkability, and low linear expansion coefficient can be exhibited. The diamines may be used alone or in combination of two or more.

The aromatic diamine having a benzoxazole structure is not particularly limited, and examples thereof include 5-amino-2-(p-aminophenyl)benzoxazole, 6-amino-2-(p-aminophenyl)benzoxazole and 5 -Amino-2-(m-aminophenyl)benzoxazole, 6-amino-2-(m-aminophenyl)benzoxazole, 2,2'-p-phenylenebis(5-aminobenzoxazole), 2,2' -P-phenylene bis(6-aminobenzoxazole), 1-(5-aminobenzoxazolo)-4-(6-aminobenzoxazolo)benzene, 2,6-(4,4'-diaminodiphenyl)benzo [1,2-d:5,4-d']bisoxazole, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole, 2, 6-(3,4'-diaminodiphenyl)benzo[1,2-d:5,4-d']bisoxazole, 2,6-(3,4'-diaminodiphenyl)benzo[1,2-d: 4,5-d']bisoxazole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:5,4-d']bisoxazole, 2,6-(3,3' -Diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole and the like.

Examples of aromatic diamines other than the aromatic diamines having a benzoxazole structure described above include 2,2′-dimethyl-4,4′-diaminobiphenyl and 1,4-bis[2-(4-aminophenyl). )-2-Propyl]benzene (bisaniline), 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 4,4 '-Bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(3-aminophenoxy)phenyl ] Sulfide, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl ]-1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 3,3′- Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4' -Diaminodiphenyl sulfoxide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4, 4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis[4-(4-aminophenoxy)phenyl]methane, 1,1-bis[ 4-(4-aminophenoxy)phenyl]ethane, 1,2-bis[4-(4-aminophenoxy)phenyl]ethane, 1,1-bis[4-(4-aminophenoxy)phenyl]propane, 1, 2-bis[4-(4-aminophenoxy)phenyl]propane, 1,3-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl] Propane, 1,1-bis[4-(4-aminophenoxy)phenyl]butane, 1,3- Bis[4-(4-aminophenoxy)phenyl]butane, 1,4-bis[4-(4-aminophenoxy)phenyl]butane, 2,2-bis[4-(4-aminophenoxy)phenyl]butane, 2,3-bis[4-(4-aminophenoxy)phenyl]butane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3-methylphenyl]propane , 2,2-bis[4-(4-aminophenoxy)-3-methylphenyl]propane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3 ,5-Dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]-1 ,1,1,3,3,3-hexafluoropropane, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,4-bis(4-amino) Phenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]sulfide, bis[4- (4-aminophenoxy)phenyl]sulfoxide, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl] Ether, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-amino) Phenoxy)benzoyl]benzene, 4,4'-bis[(3-aminophenoxy)benzoyl]benzene, 1,1-bis[4-(3-aminophenoxy)phenyl]propane, 1,3-bis[4-( 3-Aminophenoxy)phenyl]propane, 3,4′-diaminodiphenyl sulfide, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane , Bis[4-(3-aminophenoxy)phenyl]methane, 1,1-bis[4-(3-aminophenoxy)phenyl]ethane, 1,2-bis[4-(3-aminophenoxy)phenyl]ethane , Bis[4-(3-aminophenoxy)phenyl]sulfoxide, 4,4′-bis[ 3-(4-aminophenoxy)benzoyl]diphenyl ether, 4,4′-bis[3-(3-aminophenoxy)benzoyl]diphenyl ether, 4,4′-bis[4-(4-amino-α,α-dimethyl) Benzyl)phenoxy]benzophenone, 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylsulfone, bis[4-{4-(4-aminophenoxy)phenoxy}phenyl]sulfone 1,4-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene 1,3-bis[4-(4-amino-6-trifluoromethylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-fluorophenoxy)- α,α-Dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-methylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino- 6-cyanophenoxy)-α,α-dimethylbenzyl]benzene, 3,3′-diamino-4,4′-diphenoxybenzophenone, 4,4′-diamino-5,5′-diphenoxybenzophenone, 3,4 '-Diamino-4,5'-diphenoxybenzophenone, 3,3'-diamino-4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3 ,4'-Diamino-5'-phenoxybenzophenone, 3,3'-diamino-4,4'-dibiphenoxybenzophenone, 4,4'-diamino-5,5'-dibiphenoxybenzophenone, 3,4'-diamino -4,5'-dibiphenoxybenzophenone, 3,3'-diamino-4-biphenoxybenzophenone, 4,4'-diamino-5-biphenoxybenzophenone, 3,4'-diamino-4-biphenoxybenzophenone, 3 ,4'-diamino-5'-biphenoxybenzophenone, 1,3-bis(3-amino-4-phenoxybenzoyl)benzene, 1,4-bis(3-amino-4-phenoxybenzoyl)benzene, 1,3 -Bis(4-amino-5-phenoxybenzoyl)benzene, 1,4-bis(4-amino-5-phenoxybenzoyl)benzene, 1,3-bis(3-amino-4-biphe) Nonoxybenzoyl)benzene, 1,4-bis(3-amino-4-biphenoxybenzoyl)benzene, 1,3-bis(4-amino-5-biphenoxybenzoyl)benzene, 1,4-bis(4- Amino-5-biphenoxybenzoyl)benzene, 2,6-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzonitrile, and a part of hydrogen atoms on the aromatic ring of the above aromatic diamine. Alternatively, all or all of halogen atoms, an alkyl group having 1 to 3 carbon atoms, an alkoxyl group, a cyano group, or a halogen atom having 1 to 3 carbon atoms in which some or all of hydrogen atoms of the alkyl group or alkoxyl group are substituted with halogen atoms. Examples thereof include aromatic diamines substituted with a substituted alkyl group or an alkoxyl group.

Examples of the aliphatic diamines include 1,2-diaminoethane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, and 1,8-diaminooctane.
Examples of the alicyclic diamines include 1,4-diaminocyclohexane and 4,4′-methylenebis(2,6-dimethylcyclohexylamine).
The total amount of diamines other than aromatic diamines (aliphatic diamines and alicyclic diamines) is preferably 20% by mass or less of all diamines, more preferably 10% by mass or less, and further preferably 5% by mass or less. Is. In other words, the aromatic diamine content is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more of the total diamines.

The tetracarboxylic acids constituting the polyamic acid include aromatic tetracarboxylic acids (including their acid anhydrides), aliphatic tetracarboxylic acids (including their acid anhydrides) and alicyclic tetracarboxylic acids that are usually used in polyimide synthesis. Acids (including its acid anhydride) can be used. Among them, aromatic tetracarboxylic acid anhydrides, alicyclic tetracarboxylic acid anhydrides are preferable, aromatic tetracarboxylic acid anhydrides are more preferable from the viewpoint of heat resistance, and alicyclic ring from the viewpoint of light transmission. Group tetracarboxylic acids are more preferred. When these are acid anhydrides, the number of anhydride structures may be one or two in the molecule, but one having two anhydride structures (dianhydride) is preferable. Good. The tetracarboxylic acids may be used alone or in combination of two or more.

Examples of alicyclic tetracarboxylic acids include alicyclic tetracarboxylic acids such as cyclobutane tetracarboxylic acid, 1,2,4,5-cyclohexane tetracarboxylic acid, and 3,3′,4,4′-bicyclohexyl tetracarboxylic acid. Carboxylic acids, and their acid anhydrides. Among these, a dianhydride having two anhydride structures (for example, cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3′,4,4 '-Bicyclohexyl tetracarboxylic acid dianhydride and the like) are preferable. The alicyclic tetracarboxylic acids may be used alone or in combination of two or more.
When importance is attached to transparency, the alicyclic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of the total tetracarboxylic acids.

The aromatic tetracarboxylic acids are not particularly limited, but are preferably pyromellitic acid residues (that is, those having a structure derived from pyromellitic acid), and more preferably their acid anhydrides. Examples of such aromatic tetracarboxylic acids include pyromellitic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride, and 3 ,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride, 2,2-bis[4-(3,4-di) Carboxyphenoxy)phenyl]propanoic anhydride and the like.
When the heat resistance is important, the aromatic tetracarboxylic acid content is, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more based on the total tetracarboxylic acids.

The glass transition temperature of the polyimide film used in the present invention is, for example, 250° C. or higher, preferably 300° C. or higher, more preferably 350° C. or higher, or it is preferable that no glass transition point is observed in the region of 500° C. or lower. The glass transition temperature is obtained by differential thermal analysis (DSC).

The linear expansion coefficient (CTE) of the polymer film of the present invention is preferably −5 ppm/° C. to +45 ppm/° C., more preferably −5 ppm/° C. to +40 ppm/° C., and further preferably +1 ppm/° C. to +35 ppm. /°C, and even more preferably +1 ppm/°C to +10 ppm/°C. When the CTE is in the above range, the difference in linear expansion coefficient from a general support can be kept small, and peeling between the polyimide film and the support made of an inorganic material can be avoided even when subjected to a process of applying heat. ..

The tensile rupture strength of the polymer film in the present invention is, for example, 60 MPa or more, preferably 120 MPa or more, more preferably 240 MPa or more. There is no upper limit on the tensile breaking strength, but it is practically less than about 1000 MPa. Here, the tensile breaking strength of the polymer film means an average value in the MD direction (longitudinal direction) and the TD direction (width direction) of the polymer film.

The tensile elongation at break of the polymer film in the present invention is, for example, 10% to 200%, preferably 20% to 160%, more preferably 40% to 150%. Here, the tensile elongation at break of the polymer film means an average value in the MD direction (longitudinal direction) and the TD direction (width direction) of the polymer film.

The heat shrinkage rate of the polymer film of the present invention is preferably 0.5% or less when heated at 400° C. for 1 hour. Such characteristics are obtained by using pyromellitic acid as a tetracarboxylic acid dianhydride in an amount of 50 mol% or more and at the same time using a diamine having a paraphenylenediamine or a benzoxazole structure in an amount of 50 mol% or more among the raw materials of the polyimide film, or It can be obtained by using tetracarboxylic acid anhydride having 1 to 2 rings and paraphenylenediamine as a diamine component in an amount of 85 mol% or more.

The thickness unevenness of the polymer film in the present invention is preferably 0.1% or more and 20% or less, more preferably 12% or less, further preferably 7% or less, and particularly preferably 4% or less. If the thickness unevenness exceeds 20%, it tends to be difficult to apply to the narrow portion. The unevenness of the film thickness can be determined based on the following formula, for example, by randomly extracting about 10 points from the film to be measured with a contact type film thickness meter and measuring the film thickness.
Film thickness unevenness (%)=100×(maximum film thickness−minimum film thickness)÷average film thickness

In polymer films, in order to ensure handling and productivity, it is possible to add/contain a lubricant (particles) in the film to impart fine irregularities to the surface of the polymer film to ensure lubricity. preferable. The lubricant (particles) is preferably fine particles made of an inorganic material, such as metal, metal oxide, metal nitride, metal carbonide, metal salt, phosphate, carbonate, talc, mica, clay, etc. Particles made of clay minerals or the like can be used. Preferably, metal oxides such as silicon oxide, calcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, calcium pyrophosphate, hydroxyapatite, calcium carbonate, glass filler, phosphates and carbonates can be used. Only one kind of lubricant may be used, or two or more kinds thereof may be used.

The volume average particle diameter of the lubricant (particles) is usually 0.001 to 10 μm, preferably 0.03 to 2.5 μm, more preferably 0.05 to 0.7 μm, and further preferably 0.05 to It is 0.3 μm. The volume average particle diameter is based on the measured value obtained by the light scattering method. If the particle size is smaller than the lower limit, industrial production of the polymer film becomes difficult, while if it exceeds the upper limit, surface irregularities become too large and the bonding strength becomes weak, which may cause a practical problem.

The amount of the lubricant added is, for example, 0.02 to 5% by mass, preferably 0.04 to 1% by mass, and more preferably 0.08 to 0. It is 4% by mass. If the addition amount of the lubricant is too small, it is difficult to expect the effect of the lubricant addition, and the slipperiness may not be secured so much, which may hinder the production of the polymer film.If the addition amount is too large, the surface roughness of the film may be uneven. If it becomes too large and slipperiness can be ensured, it may lead to problems such as a decrease in smoothness, a decrease in breaking strength and a breaking elongation of the polymer film, and an increase in CTE.

When the lubricant (particles) is added to and contained in the polymer film, it may be a single-layer polymer film in which the lubricant is uniformly dispersed. For example, one surface is a polymer film containing the lubricant. It may be a multi-layered polymer film composed of a polymer film having a small amount of lubricant, even if the other surface does not contain a lubricant or contains a lubricant. In such a multi-layered polymer film, fine irregularities are provided on the surface of one layer (film) so that the layer (film) can secure the slipperiness and ensure good handling properties and productivity. it can.

Multilayer polymer film, in the case of a film produced by the melt-stretching film-forming method, for example, first, a polymer film raw material that does not contain a lubricant is formed into a film, and at least one surface of the film placed in the middle of the process, It can be obtained by applying a resin containing a lubricant. Of course, on the contrary, a polymer film raw material containing a lubricant is formed into a film, and a polymer film raw material containing no lubricant is applied during the process or after the film formation is completed to obtain a film. You can also do it.

The same applies to the case of a polymer film obtained by using a solution film-forming method such as a polyimide film. For example, as a polyamic acid solution (a polyimide precursor solution), a lubricant (preferably an average particle size of 0.05 to 2.5 μm) to 0.02% by mass to 50% by mass (preferably 0.04 to 3% by mass, more preferably 0.08 to 1.2% by mass) based on the polymer solid content in the polyamic acid solution. With the polyamic acid solution contained, the lubricant is not contained or the content thereof is small (preferably less than 0.02% by mass, more preferably 0.01% by mass or less based on the polymer solid content in the polyamic acid solution). Can be produced using two polyamic acid solutions that are

The method for forming a multilayer (lamination) of the multilayer polymer film is not particularly limited as long as there is no problem in adhesion of both layers, and any method may be used as long as it adheres without an adhesive layer or the like.
In the case of a polyimide film, for example, i) a method of producing one polyimide film and then continuously applying the other polyamic acid solution on the polyimide film to imidize, ii) casting one polyamic acid solution After producing a polyamic acid film, the other polyamic acid solution is continuously applied onto this polyamic acid film, and then imidized, iii) by coextrusion, iv) containing no lubricant or its content An example is a method of applying a polyamic acid solution containing a large amount of lubricant by spray coating, T-die coating, or the like to a film formed with a polyamic acid solution containing a small amount of imide to imidize the film. In the present invention, it is preferable to use the above methods i) to ii).

The ratio of the thickness of each layer in the multilayer polymer film is not particularly limited, but the polymer layer containing a large amount of lubricant (a) layer, the polymer containing no lubricant or a small amount thereof When the layer is the (b) layer, the thickness ratio of the (a) layer/(b) layer is preferably 0.05 to 0.95. When the thickness ratio of the (a) layer/(b) layer exceeds 0.95, the smoothness of the (b) layer tends to be lost, while when it is less than 0.05, the effect of improving the surface characteristics tends to be insufficient. Lubricity may be lost.

The polymer film according to the present invention is preferably obtained in the form of a long film having a width of 300 mm or more and a length of 10 m or more at the time of its production, and a roll-shaped polyimide wound on a winding core. More preferably, it is in the form of a film.

<Surface activation treatment of polymer film>
The polymer film of the present invention is surface activated using an alkaline solution containing oxyalkylamine. The oxyalkylamine preferably has 1 to 15 carbon atoms, more preferably 1 to 10 carbon atoms, and further preferably 1 to 5 carbon atoms.
The oxyalkylamine is preferably at least one selected from the group consisting of monooxymonoamine and monoaminopolyhydric alcohol.

Oxyalkylamines preferably used in the present invention include ethanolamine, propanolamine, butanolamine, N-(β-aminoethyl)ethanolamine, N-methylethanolamine, N-ethylethanolamine, triethanolamine, N, Monooxymonoamines such as N-dimethylethanolamine, N,N-diethylethanolamine, N,N-dimethylpropanolamine, N,N-diethylpropanolamine, N,N-dipropylpropanolamine; diethanolamine, dimethanolamine, Examples thereof include monoamino polyhydric alcohols such as dipropanolamine, dibutanolamine and dihexanolamine. The oxyalkylamine particularly preferably used in the present invention is monooxymonoamine, most preferably ethanolamine and propanolamine.

As the alkaline solution containing oxyalkylamine in the present invention, an aqueous solution, an alcohol solution or a solvent solution is preferably used. Examples of the alcohol solution include a methanol solution, an ethanol solution, an isopropanol solution, a normal propanol solution, and a butanol solution. As the solvent solution, normal methylpyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide and the like can be used.
Among them, the alkaline solution is preferably an aqueous solution from the viewpoint of workability.

The content of oxyalkylamine in the alkaline solution of the present invention is not particularly limited, and a stock solution of oxyalkylamine may be used. However, from the viewpoint of workability, the content of the oxyalkylamine is preferably 2 to 60% by mass, more preferably 3 to 45% by mass, and further preferably 5 to 33% by mass in 100% by mass of the alkaline solution.

The alkaline solution containing an oxyalkylamine in the present invention, as an additional component, an inorganic alkali such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia, monomethylamine, monoethylamine, dimethylamine, diethylamine, trimethylamine, It is possible to add an organic alkali such as triethylamine, tetramethylammonium salt or tetraethylammonium salt, or a low molecular weight compound derived from ammonia such as urea. Above all, it is preferable to use potassium hydroxide.
The total amount of the additional component added is preferably equal to or less than the content of the oxyalkylamine. The content of the additional component is, for example, 0 to 10 mass% in 100 mass% of the alkaline solution, and preferably 0 to 5 mass %.

In addition to these components, a known surfactant or the like can be added for the purpose of adjusting the wettability of the alkaline solution with respect to the polymer film.

<Protective film>
In the present invention, a protective film can be used if necessary. The protective film is, literally, an object to be protected, which plays a role of protecting the object from contamination and scratches.In the present invention, the divided polymer films are combined into an inorganic substrate. It plays the role of saving labor in the laminating process.

The protective film of the present invention may be composed of a base film and an adhesive. As the base material film, in addition to general PET film, PEN film, polypropylene film, nylon film, etc., heat resistant super engineering plastic film such as PPS film, PEEK film, aromatic polyamide film, polyimide film, polyimide benzazole film, etc. Can be used.

The base material of the protective film preferably used in the present invention is a PET film which has been subjected to an annealing treatment for improving dimensional stability, a PEN film which has also been subjected to an annealing treatment, and a polyimide film.

As the pressure-sensitive adhesive used in the protective film of the present invention, known pressure-sensitive adhesives such as silicone-based, acrylic-based and polyurethane-based can be used. The protective film of the present invention protects a device forming surface of a polymer film which is a base material of a flexible electronic device. Therefore, it is preferable to use a pressure-sensitive adhesive of a type that minimizes the transfer of the pressure-sensitive adhesive component, or the transfer component is dry or can be easily removed by wet cleaning. In the present invention, for example, a pressure-sensitive adhesive using a side-chain crystalline polymer having a property that the pressure-sensitive adhesive force is reduced by cooling can be used.

<Means for adhering the inorganic substrate and the polymer film>
In the present invention, the means for adhering the inorganic substrate and the polymer film includes (1) means for adhering the polymer film and the inorganic substrate by surface-activating the surface of the polymer film to be bonded with the inorganic substrate with the alkaline solution. (2) A means for adhering the polymer film and the inorganic substrate by treating the surface of the inorganic substrate to be adhered with the polymer film with a silane coupling agent, (3) adhering the polymer film and the inorganic substrate with an adhesive or an adhesive. Means may be used, or these may be used in combination.
In the present invention, the means for adhering the inorganic substrate and the polymer film uses the above (1) as an essential means, and the above (1) and (2), (1) and (3), or (1) and the above. A combination of (2) and (3) may be used, and (2) and/or (3) may be performed after (1).

Adhesion of Inorganic Substrate and Polymer Film with Alkaline Solution The surface of the polymer film to be bonded to the inorganic substrate is preferably coated with the alkaline solution, and the polymer film is preferably immersed in the alkaline solution.

As a coating method, general liquid coating such as spin coating method, curtain coating method, dip coating method, slit die coating method, gravure coating method, bar coating method, comma coating method, applicator method, screen printing method, spray coating method, etc. A method can be illustrated. When the coating method in the liquid phase is used, it is preferable that the coating is dried immediately after coating and further heat treatment (drying treatment) is performed at about 90±30° C. for several tens of seconds to 10 minutes.

Examples of the dipping method include a method in which a predetermined container is filled with the alkaline solution, and the polymer film is dipped at a predetermined temperature for a predetermined time while stirring the alkaline solution. The temperature is, for example, 0 to 80°C, preferably 10 to 60°C, more preferably 15 to 38°C, and even more preferably 15 to 30°C. If the temperature exceeds this range, the polymer film may be dissolved. On the other hand, if the temperature does not reach the predetermined range, the treatment becomes insufficient, and uneven adhesion strength is likely to occur.
The time is, for example, 1 second to 30 minutes, preferably 5 seconds to 10 minutes, and more preferably 10 seconds to 5 minutes. When the processing time exceeds a predetermined time, problems such as dissolution of the film and reduction in strength may occur. Further, if the processing time is less than a predetermined range, the processing becomes uneven, and spots are likely to occur. When the dipping method is used, it is preferable that after dipping, it is washed multiple times with water, and heat treatment (drying treatment) is performed at about 90±30° C. for several tens of seconds to 10 minutes.

Adhesion of Inorganic Substrate and Polymer Film with Silane Coupling Agent The silane coupling agent physically or chemically intervenes between the inorganic substrate (temporary support) and the polymer film to enhance the adhesive force between them. A compound having an action.
Specific preferred examples of the silane coupling agent include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-( Aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, 2- (3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, vinyltrichlorosilane, Vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycid Xypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane , 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxysilane, tris-(3-trimethoxy Examples include silylpropyl) isocyanurate, chloromethylphenethyltrimethoxysilane, chloromethyltrimethoxysilane, aminophenyltrimethoxysilane, aminophenethyltrimethoxysilane, aminophenylaminomethylphenethyltrimethoxysilane, and hexamethyldisilazane.

In addition, n-propyltrimethoxysilane, butyltrichlorosilane, 2-cyanoethyltriethoxysilane, cyclohexyltrichlorosilane, decyltrichlorosilane, diacetoxydimethylsilane, diethoxydimethylsilane, dimethoxydimethylsilane, dimethoxydiphenylsilane, dimethoxymethylphenyl. Silane, dodecyltrichlorosilane, dodecyltrimethoxysilane, ethyltrichlorosilane, hexyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrimethoxysilane, n-octyltrichlorosilane, n-octyltriethoxysilane, n-octyltrimethoxysilane, Triethoxyethylsilane, triethoxymethylsilane, trimethoxymethylsilane, trimethoxyphenylsilane, pentyltriethoxysilane, pentyltrichlorosilane, triacetoxymethylsilane, trichlorohexylsilane, trichloromethylsilane, trichlorooctadecylsilane, trichloropropylsilane, Trichlorotetradecylsilane, trimethoxypropylsilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, dimethoxymethylvinylsilane, trichlorovinylsilane, triethoxyvinylsilane, vinyltris(2-methoxyethoxy)silane, trichloro 2-Cyanoethylsilane, diethoxy(3-glycidyloxypropyl)methylsilane, 3-glycidyloxypropyl(dimethoxy)methylsilane, 3-glycidyloxypropyltrimethoxysilane and the like can also be used.

Among such silane coupling agents, the silane coupling agent preferably used in the present invention is preferably a silane coupling agent having a chemical structure having one silicon atom per molecule of the coupling agent.

Particularly preferred silane coupling agents include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl). )-3-Aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, 2-(3 , 4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, aminophenyltrimethoxysilane, Examples thereof include aminophenethyltrimethoxysilane and aminophenylaminomethylphenethyltrimethoxysilane. When particularly high heat resistance is required in the process, it is desirable to connect Si and an amino group with an aromatic group.
In the present invention, a phosphorus-based coupling agent, a titanate-based coupling agent, etc. may be used in combination, if necessary.

<How to apply silane coupling agent>
As a coating method of the silane coupling agent, a liquid phase coating method or a gas phase coating method can be used.
As the coating method in the liquid phase, using a solution obtained by diluting a silane coupling agent with a solvent such as alcohol, a spin coating method, a curtain coating method, a dip coating method, a slit die coating method, a gravure coating method, a bar coating method, Typical liquid application methods such as a comma coat method, an applicator method, a screen printing method and a spray coat method can be exemplified. When the coating method in the liquid phase is used, it is preferable that the coating is dried immediately after coating and further heat-treated at about 100±30° C. for several tens of seconds to 10 minutes. By the heat treatment, the silane coupling agent and the surface of the coated surface are bonded by a chemical reaction.

Examples of the coating method in the vapor phase include a method of exposing the substrate to the vapor of the silane coupling agent, that is, the silane coupling agent in a substantially gaseous state. The vapor of the silane coupling agent can be obtained by heating the silane coupling agent in a liquid state to a temperature of 40° C. to the boiling point of the silane coupling agent. The boiling point of the silane coupling agent varies depending on the chemical structure, but is generally in the range of 100 to 250°C. However, heating at 200° C. or higher is not preferable because it may cause a side reaction on the organic group side of the silane coupling agent.

The environment for heating the silane coupling agent may be under pressure, at about normal pressure, or at reduced pressure. However, in order to accelerate vaporization of the silane coupling agent, it is preferably at about normal pressure or under reduced pressure. Since many silane coupling agents are flammable liquids, it is preferable to carry out the vaporization work in a closed container after replacing the container with an inert gas.

The time for exposing the inorganic substrate to the silane coupling agent is not particularly limited, but is, for example, 20 hours or less, preferably 60 minutes or less, more preferably 15 minutes or less, and further preferably 1 minute or less.

The temperature of the inorganic substrate during the exposure of the inorganic substrate to the silane coupling agent is controlled to an appropriate temperature between −50° C. and 200° C. depending on the type of the silane coupling agent and the required thickness of the silane coupling agent layer. It is preferable.

The inorganic substrate exposed to the silane coupling agent is preferably heated to 70°C to 200°C, more preferably 75°C to 150°C after the exposure. By such heating, the hydroxyl group or the like on the surface of the inorganic substrate reacts with the alkoxy group or silazane group of the silane coupling agent, and the silane coupling agent treatment is completed. The time required for heating is 10 seconds or more and 10 minutes or less. If the temperature is too high or the time is too long, the coupling agent may deteriorate. If it is too short, the treatment effect cannot be obtained. If the substrate temperature during exposure to the silane coupling agent is already 80° C. or higher, post-heating can be omitted.

It is preferable that the surface of the inorganic substrate on which the silane coupling agent is applied is held downward and exposed to the silane coupling agent vapor. In the liquid-phase coating method, the coating surface of the inorganic substrate inevitably faces upward during the coating and before and after coating, so that floating foreign substances under the working environment may be deposited on the surface of the inorganic substrate. However, since the inorganic substrate can be held downward by the vapor-phase coating method, it is possible to significantly reduce the adhesion of foreign matter in the environment.
In addition, it is preferable to clean the surface of the inorganic substrate before the treatment with the silane coupling agent by a means such as short wavelength UV/ozone irradiation or a liquid cleaning agent.

The coating amount (thickness) of the silane coupling agent is theoretically sufficient to be one molecular layer, and a mechanically designable level of thickness is sufficient. Generally, the thickness of the silane coupling agent layer is less than 400 nm (less than 0.4 μm), preferably 200 nm or less (0.2 μm or less), and more preferably 100 nm or less (0.1 μm or less) in practice. The thickness is more preferably 50 nm or less, still more preferably 10 nm or less. However, in the case of a region of 5 nm or less in calculation, it is assumed that the silane coupling agent is present as a cluster rather than as a uniform coating film, which is not preferable. The film thickness of the silane coupling agent layer can be obtained by ellipsometry or by calculation from the concentration of the silane coupling agent solution at the time of coating and the coating amount.

An inorganic substrate that has been treated by UV ozone treatment is used for an inorganic substrate that has been treated with a silane coupling agent, an untreated inorganic substrate, or an inorganic substrate that has been washed with ultrapure water or the like. be able to. The UV ozone treatment in the present invention means a treatment of irradiating with ultraviolet rays having a wavelength of, for example, 270 nm or less, preferably 210 nm or less, more preferably 180 nm or less in the presence of oxygen at a relatively short distance. Short-wavelength ultraviolet rays turn oxygen in the atmosphere into ozone, and the ultraviolet rays themselves are attenuated. In the present invention, the distance between the light source and the object to be processed is, for example, 30 mm or less, preferably 16 mm or less, and more preferably 8 mm or less.

In the present invention, the treatment with the silane coupling agent alone may cause excessive adhesion of the inorganic substrate and the polymer film, which may hinder peeling. Adjustment can be made by reducing the coating amount of the silane coupling agent, but since treatment unevenness is likely to occur, in the present invention, after the silane coupling agent treatment, UV ozone treatment or the like is performed to introduce the silane coupling agent. A method for deactivating the functional group is recommended.

Adhesion of Inorganic Substrate to Polymer Film by Adhesive or Adhesive As the adhesive or the adhesive, known adhesives or adhesives such as silicone resin, epoxy resin, acrylic resin, polyester resin can be used. In the present invention, for example, a pressure-sensitive adhesive using a side-chain crystalline polymer having a property that the pressure-sensitive adhesive force is reduced by cooling can be used.
The adhering means may be an adhering means using an adhesive/adhesive having a thickness of 5 μm or less, or may be an adhering means using substantially no adhesive/adhesive.
In the present invention, the inorganic substrate side is subjected to a silane coupling agent treatment, an organic ozone treatment such as a UV ozone treatment, and an activation treatment. Similarly, the polymer film side is subjected to vacuum plasma treatment, atmospheric pressure plasma treatment, corona treatment, An adhesive method may be used in which activation treatment such as flame treatment, itro treatment, UV ozone treatment, and exposure treatment to an active gas is performed, and both treatment surfaces are brought into close contact with each other and pressure and heat treatment are performed.

<Film laminating method>
In the present invention, at least the surface of the inorganic substrate and the surface of the activated polymer film are superposed, and heat and pressure can be applied to perform the adhesion.
The bonding of the inorganic substrate and the polymer film is preferably performed by heating and pressurizing the surface-activated inorganic substrate and the surface-activated polymer film. In this case, the surface of the inorganic substrate to be attached to the polymer film is preferably treated with a silane coupling agent. On the other hand, a surface-activated inorganic substrate or a non-surface-activated inorganic substrate and a surface-activated polymer film are bonded to each other via a pressure-sensitive adhesive layer or adhesive layer having a thickness of 5 μm or less. Good.
The pressurization/heat treatment may be performed, for example, under pressure in an atmospheric pressure atmosphere or in vacuum while performing heating such as pressing, laminating, or roll laminating. A method of applying pressure and heating in a flexible bag can also be applied. From the viewpoint of improving productivity and reducing the processing cost brought about by high productivity, press or roll laminating in an air atmosphere is preferable, and a method using rolls (roll laminating or the like) is particularly preferable.

The pressure during the heat treatment under pressure is preferably 0.1 MPa to 10 MPa, more preferably 0.3 MPa to 5 MPa. If the pressure is too high, the support may be damaged, and if the pressure is too low, some portions may not adhere to each other, resulting in insufficient adhesion.
The temperature for the pressure heat treatment is such that it does not exceed the heat resistant temperature of the polymer film used. In the case of a non-thermoplastic polyimide film, it is preferably treated at 80°C to 400°C, more preferably 90°C to 350°C.

The pressure heat treatment can be performed separately in a pressure process and a heating process. In this case, first, the polymer film and the inorganic substrate are pressurized (preferably about 0.2 to 50 MPa) at a relatively low temperature (for example, a temperature of less than 120° C., preferably 95° C. or less) to secure the adhesion between them. After that, at a low pressure (preferably less than 0.2 MPa, more preferably 0.1 MPa or less) or at a relatively high temperature (eg 120° C. or higher, preferably 120 to 250° C., more preferably 150 to 230° C.) at normal pressure. By heating, the chemical reaction at the adhesion interface is promoted and the polymer film and the temporary supporting inorganic substrate can be laminated.

In the present invention, it is preferable to control the moisture absorption rate of the polymer film when the polymer film and the inorganic substrate are bonded together to be 1.8% or less. The moisture absorption rate of such a polymer film means the moisture absorption rate immediately before the polymer film and the inorganic substrate are pressure-bonded. The moisture absorption rate of the polymer film depends on the temperature and humidity inside the room where the polymer film is left. Further, since it takes time to absorb and release moisture, it is important to evaluate the measurement after leaving it for a sufficiently long time under a certain condition for at least 24 hours or more.

If the amount of the absorbed moisture is too large, it causes blisters when heat is applied in a later step. On the other hand, if the amount is too small, the adhesiveness to the inorganic substrate may become stable. That is, the chemical reaction on the surface of each of the polymer film and the inorganic substrate is influenced by the moisture contained in the polymer film. The moisture absorption rate of the polymer film is, for example, 1.5% or less, preferably 1.2% or less. The lower limit of the moisture absorption rate of the polymer film is, for example, 0.1%, preferably 0.2%, more preferably 0.4%.

<Manufacturing means for flexible electronic devices>
When the laminate of the present invention is used, an electronic device is formed on the polymer film of the laminate by using the existing equipment and process for manufacturing an electronic device, and the polymer film is peeled from the laminate, thereby providing a flexible structure. Electronic devices can be made.
The electronic device in the present invention includes a wiring board that carries electrical wiring, active elements such as transistors and diodes, and electronic circuits including passive devices such as resistors, capacitors, and inductors, as well as pressure, temperature, light, humidity, and the like. A sensor element, a light emitting element, an image display element such as a liquid crystal display, an electrophoretic display, a self-luminous display, a wireless or wired communication element, an arithmetic element, a memory element, a MEMS element, a solar cell, a thin film transistor, and the like.

<Means for peeling the polymer film from the inorganic substrate>
The means for peeling the polymer film from the support is not particularly limited, and a known method may be used. As a method of peeling the polymer film from the laminate, a method of irradiating strong light from the inorganic substrate side to thermally decompose the adhesive site between the inorganic substrate and the polymer film, or by photodecomposing it, and to preliminarily measure the adhesive strength. After weakening, peeling the polymer film with a force less than the elastic strength limit of the polymer film, exposing it to heated water, heated steam, etc. to weaken the bond strength between the inorganic substrate and polymer film interface and peel it off, etc. Can be illustrated.

Other peeling methods include a method of rolling from the end with tweezers, a method of sticking an adhesive tape on one side of a cut portion of a polymer film with a device and then rolling from the tape portion, a method of removing a polymer film with a device. A method of vacuum adsorbing one side of the cut portion and then winding it from that portion, or by not adhering a part of the polymer film to the inorganic plate in advance, or by protruding a part of the polymer film from the inorganic substrate to obtain a gripping white A method etc. can be adopted.

In the present invention, it is preferable that the adhesive strength at 90° peeling between the inorganic substrate and the polymer film is within a predetermined range. When a thermoplastic film such as a PET film is used as the polymer film, it is assumed that amorphous silicon or an organic semiconductor is used as the semiconductor. Therefore, the adhesive strength in 90 degree peeling after heat treatment at 140° C. for 30 minutes. May be evaluated as
On the other hand, when a polyimide film is used as the polymer film, it is evaluated as the adhesive strength in 90 degree peeling after heat treatment at 420° C. for 30 minutes in that a dehydrogenation step of amorphous silicon and a polycrystallization step are assumed. Good. When a polyethylene naphthalate film is used as the polymer film, it may be evaluated as the adhesive strength in 90 degree peeling after heat treatment at 250° C. for 30 minutes. When an LCP film is used as the polymer film, it may be evaluated as the adhesive strength in 90 degree peeling after heat treatment at 300° C. for 30 minutes.
The adhesive strength between the inorganic substrate and the polymer film when peeled at 90 degrees is, for example, 0.1 N/cm or more and less than 10 N/cm, preferably 0.2 N/cm or more and 6 N/cm or less, more preferably 0.3 N/cm or more and 4 N or more. /Cm or less, more preferably 0.4 N/cm or more and 3 N/cm or less.
Heat treatment of the inorganic substrate and the polymer film when the inorganic substrate is treated with a silane coupling agent (for example, 140° C. for 30 minutes for polyethylene terephthalate film, 420° C. for 30 minutes for polyimide film, 250° C. for 30 minutes for polyethylene naphthalate). In the case of a liquid crystal polymer, the adhesive strength in 90° peeling after 300° C. for 30 minutes) is, for example, 1.5 N/cm or more and 10 N/cm or less, preferably 1.7 N/cm or more, and more preferably 1.9 N/cm or more. , And more preferably 2.1 N/cm or more.
When the inorganic substrate is treated with a silane coupling agent, the adhesive strength of the inorganic substrate and the polymer film at 90° peeling after the heat treatment is preferably lower than the adhesive strength before the heat treatment (initial adhesive strength).
When the inorganic substrate is not treated with a silane coupling agent, the adhesive strength in 90 degree peeling after heat treatment between the inorganic substrate and the polymer film is, for example, 0.1 N/cm or more and less than 1.5 N/cm, preferably 0.2 N/cm. cm or more, more preferably 0.3 N/cm or more, still more preferably 0.4 N/cm or more.
When the inorganic substrate is not treated with the silane coupling agent, the adhesive strength of the inorganic film and the polymer film at 90° peeling after the heat treatment is preferably higher than the adhesive strength before the heat treatment (initial adhesive strength).

In the present invention, it is recommended that the peeling angle at the time of peeling is π/6 radians (30 degrees) or less, more preferably π/12 radians (15 degrees) or less, and further π/24 radians ( It is even more preferable to set it to 7.5 degrees or less. When the lower limit of the peeling angle is 0, it corresponds to natural peeling, and in this case, troubles such as blister generation and film peeling are likely to occur in the electronic device processing step. The lower limit of the peeling angle of the present invention is preferably 1.0 degree, more preferably about 2 degrees.

In the present invention, it is also useful to attach another reinforcing base material to the portion to be peeled off in advance and peel the whole reinforcing base material. When the flexible electronic device to be peeled is the backplane of the display device, it is possible to obtain the flexible display device by pasting the front plane of the display device in advance, integrating them on the inorganic substrate, and then peeling them off at the same time. is there.

In the present invention, patterning treatment can be performed on the inorganic substrate side, the polymer film side, or both. The patterning in the present invention means controlling the degree of surface treatment of the polymer film, the inorganic substrate, or both (for example, surface activation treatment with an alkaline solution, surface activation treatment with a silane coupling agent), It means to create a part where the adhesive force is relatively strong and a part where the adhesion is weak. In the present invention, an electronic device is formed in a region where the adhesion between the polymer film and the inorganic substrate is weakened by the patterning treatment (referred to as an easily peelable portion), and then a cut is made in the outer periphery of the region to form the polymer film A flexible electronic device can be obtained by peeling the area on which the electronic device is formed from the inorganic substrate. This method makes it easier to separate the polymer film and the inorganic substrate.

As a method of making a cut in the polymer film along the outer periphery of the easily peelable portion of the laminate, a method of cutting the polymer film with a cutting tool such as a blade or a method of relatively scanning the laser and the laminate can be used. A method of cutting a molecular film, a method of cutting a polymer film by relatively scanning a water jet and a laminate, a method of cutting a polymer film while slightly cutting a glass layer by a dicing device for a semiconductor chip, etc. be able to. Further, a combination of these methods, a method of superimposing an ultrasonic wave on a cutting tool, and a method of improving the cutting performance by adding a reciprocating motion or a vertical motion can be appropriately adopted.

When making a notch in the polymer film on the outer periphery of the easily peelable portion of the laminate, the position of the notch may include at least a part of the easily peelable portion, and basically it may be cut according to a predetermined pattern. It may be appropriately selected from the viewpoints of error absorption, productivity, and the like.

Hereinafter, the present invention will be described more specifically by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples. The methods for evaluating the physical properties in the following examples are as follows.

<Reduced viscosity of polyamic acid solution>
The solution dissolved in N,N-dimethylacetamide so that the polymer concentration was 0.2 g/dl was measured at 30° C. using an Ubbelohde type viscosity tube.

<Thickness of polymer film>
The thickness of the polymer film was measured using a micrometer (“Millitron 1245D” manufactured by Fine Luff).

<Tensile elastic modulus, tensile breaking strength and tensile breaking elongation of polymer film>
From the polymer film to be measured, strip-shaped test pieces of 100 mm×10 mm in the flow direction (MD direction) and the width direction (TD direction) were cut out, and a tensile tester (“Autograph (registered by Shimadzu Corporation)” (Trademark); model name AG-5000A"), tensile elastic modulus, tensile breaking strength and tensile breaking elongation were measured in the MD direction and the TD direction under conditions of a tensile speed of 50 mm/min and a chuck distance of 40 mm. ..

<Coefficient of linear expansion (CTE) of polymer film>
With respect to the flow direction (MD direction) and the width direction (TD direction) of the polymer film to be measured, the expansion/contraction ratio was measured under the following conditions, and the intervals of 15°C (30°C to 45°C, 45°C to 60°C, () was measured up to 300° C., and an average value of all measured values measured in the MD direction and the TD direction was calculated as a coefficient of linear expansion (CTE).
Device name: MAC Science Co., Ltd. "TMA4000S"
Sample length: 20 mm
Sample width: 2 mm
Temperature rising start temperature: 25°C
Temperature rise end temperature: 400°C
Temperature rising rate: 5°C/min Atmosphere: Argon initial load: 34.5 g/mm ²

<Heat shrinkage of polymer film>
It was measured by the method specified in IEC 61189-2, Test 2X02, with heating conditions of 400° C. for 1 hour.

<Moisture absorption rate of polymer film>
It was measured by the A method specified in JIS K7251.

<Adhesive strength 90 degree peeling method>
From the laminated plate, a portion to be used for measurement was cut into a 100 mm square, and the adhesive strength between the inorganic substrate and the polymer film was measured under the following conditions according to the 90° peeling method described in JIS C6481.
Device name: "Autograph (registered trademark) AG-IS" manufactured by Shimadzu Corporation
Measurement temperature: Room temperature Peeling speed: 50 mm/min Atmosphere: Atmospheric measurement sample width: 10 mm

<Production of polyimide film>
[Production Example 1]
(Preparation of polyamic acid solution)
After nitrogen-substituting the inside of a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring bar, 398 parts by mass of 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) and paraphenylenediamine( 147 parts by mass of PDA) dissolved in 4600 parts by mass of N,N-dimethylacetamide and added thereto, and a dispersion obtained by dispersing colloidal silica as a lubricant in dimethylacetamide (manufactured by Nissan Kagaku Kogyo "Snowtex (registered trademark)". )DMAC-ST30") was added so that the silica (lubricant) was 0.08 mass% with respect to the total amount of polymer solids in the polyamic acid solution, and the mixture was stirred at a reaction temperature of 25°C for 24 hours and then added to Table 1. A brown viscous polyamic acid solution V1 having the reduced viscosity shown in was obtained.

(Preparation of polyimide film)
Using the slit die, the polyamic acid solution V1 obtained above was used to form a final film thickness (on a smooth surface) of a long polyester film having a width of 1500 mm ("A-4100" manufactured by Toyobo Co., Ltd.). It was applied so that the film thickness after imidization) would be 25 μm, dried at 105° C. for 20 minutes, and then peeled from the polyester film to obtain a self-supporting polyamic acid film having a width of 1420 mm.

Then, the obtained self-supporting polyamic acid film was stretched 1.1 times in the length direction by the speed difference of the transport rolls, and then stretched 1.05 times in the width direction by a pin tenter, and the temperature was 150°C to 420°C. The temperature is increased stepwise in the area (180°C x 5 minutes for the 1st step, 270°C x 10 minutes for the 2nd step, 420°C x 5 minutes for the 3rd step) to imidize, and the pin gripping parts at both ends Was dropped through a slit to obtain a long polyimide film F1 (1000 m roll) having a width of 1290 mm. The characteristics of the obtained film F1 are shown in Table 2.

[Production Example 2]
(Preparation of polyamic acid solution)
After nitrogen-substituting a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod, 223 parts by mass of 5-amino-2-(p-aminophenyl)benzoxazole (DAMBO) and N,N-dimethylacetamide 4416 And 217 parts by mass of pyromellitic dianhydride (PMDA), and then colloidal silica as a lubricant is dispersed in dimethylacetamide (Nissan Chemical Co., Ltd. "Snowtex"). (Registered trademark) DMAC-ST30") and silica (lubricant) are added so that the total polymer solid content in the polyamic acid solution is 0.09% by mass, and the mixture is stirred at a reaction temperature of 25°C for 36 hours. A brown viscous polyamic acid solution V2 having a reduced viscosity shown in Table 1 was obtained.

<Production of polyimide film>
The polyamic acid solution V2 obtained above was used in place of the polyamic acid solution V1, and a smooth surface (non-slip material) of a long polyester film (“A-4100” manufactured by Toyobo Co., Ltd.) having a width of 800 mm was formed using a slit die. On the surface) so that the final film thickness (film thickness after imidization) is 38 μm, and is dried at 105° C. for 25 minutes, then peeled from the polyester film, and the first step is performed at 150° C. by a pin tenter. ×5 minutes, 2nd step 220° C.×5 minutes, 3rd step 495° C.×10 minutes, imidized by heat treatment, the pin gripping parts on both ends are dropped by slits, and a long polyimide film F2 (width 645 mm) 1000 m roll) was obtained. The characteristics of the obtained film F2 are shown in Table 2.

<Other polymer films>
The following were used as other polymer films. Kapton H was a commercial product manufactured by Toray DuPont, PEN film was manufactured by Teijin DuPont, and LCP film was a commercial product by Kuraray.

<Preparation of alkaline solution for surface activation treatment>
15 parts by mass of ethanolamine and 85 parts by mass of deionized water were mixed and stirred to obtain an alkaline solution A1. Separately, 10 parts by mass of ethanolamine, 2 parts by mass of KOH, and 88 parts by mass of deionized water were mixed and stirred to obtain an alkaline solution A2. 5 parts by mass of NaOH was dissolved in 95 parts by mass of deionized water to obtain an alkaline solution A3. First-grade reagents were used for ethanolamine, KOH, and NaOH.

<Production of surface activated polymer film>
The film F1 was cut into 300 mm×420 mm, fixed to a stainless steel metal frame, filled with an alkaline solution (treatment chemical solution) whose temperature was adjusted to a predetermined temperature shown in Table 3, and gently stirred in a water tank for a predetermined time. Immediately after soaking and pulling up, soak in a water tank filled with deionized water for 10 seconds, drain sufficiently, then soak in another deionized water tank for 10 seconds, drain thoroughly, wash with running water, warm air at 60°C It was dried in a dryer for 3 minutes and subjected to surface activation treatment (Example 1). Hereinafter, the same operation was performed except that the polymer film, the alkaline solution (treatment liquid chemical), the treatment temperature and the treatment time were changed to those shown in Table 3 (Examples 2 to 20 and Comparative Examples 1 to 5).

<Inorganic substrate>
370×470 mm, 0.7 mm thick Lotus Glass made by Corning and using UV/O ₃ cleaning and reforming apparatus made by Run Technical Service Co., Ltd., UV from a distance of about 20 mm from the UV lamp in the atmosphere. Irradiation was carried out for 5 minutes. This glass substrate was used as an untreated substrate. Note that the UV lamp emits bright lines with wavelengths of 185 nm (a short wavelength capable of generating ozone that accelerates the inactivation treatment) and 254 nm, and at this time, the illuminance is measured by an illuminance meter “UV-M03AUV (ORC Co., Ltd.; Measured at wavelength)" was 20 mW/cm ² .

The untreated substrate was subjected to a silane coupling agent treatment (SC agent treatment) by vapor phase coating. 100 parts by mass of a silane coupling agent (“KBM-903” manufactured by Shin-Etsu Chemical Co., Ltd.: 3-aminopropyltrimethoxysilane) was charged into an evaporation vat inside the chamber so that the oxygen concentration was 0.1% or less at atmospheric pressure. Nitrogen gas was introduced until the temperature reached 80° C., and the temperature of the vat charged with the silane coupling agent was raised to 80° C. Next, the untreated substrate was held horizontally at a position 100 mm away from the liquid surface of the silane coupling agent in the horizontal direction, and gently conveyed at a speed of 7 mm/sec for exposure to the silane coupling agent vapor. The glass temperature was controlled between 95° C. and 105° C. by far-infrared heating and heat treatment was performed for about 3 minutes. This substrate was used as an SC agent-coated inorganic substrate.

Example 1
The surface-activated polymer film P1 and the SC agent-coated inorganic substrate were laminated so that the treated surfaces were aligned, and the inorganic substrate side temperature was 100° C., the roll pressure was 5 kgf/cm ² , and the roll speed was 5 mm/using a roll laminator manufactured by MCK. Temporarily laminated in seconds. The polymer film after the temporary lamination was not peeled off by its own weight, but had such adhesiveness that it was easily peeled off when scratching the edge of the film. After that, the obtained temporary laminate substrate was put in a clean oven, heated at 120° C. for 30 minutes, and then allowed to cool to room temperature to obtain a laminated body L1.
The resulting laminate was evaluated for 90° peel adhesive strength between the film and the substrate, as well as appearance quality after heat treatment in an oven and 90° peel adhesive strength. The results are shown in Table 3. The heat treatment was performed at 420° C. for 30 minutes.
The laminate is manufactured in a laboratory where the temperature is kept at 25°C ± 2°C and the humidity is 55% ± 3%, and the surface-activated polymer film is laminated in this laboratory after being left for 24 hours or more. I went.

Examples 2-20
The surface activation treated polymer film, the alkaline solution (treatment chemical solution) and the inorganic substrate were changed, and the same operation as in Example 1 was carried out to obtain a laminate. The obtained laminated body was evaluated in the same manner as in Example 1. The results are shown in Table 3. When the PEN film was used, the heat treatment condition was 250° C. for 30 minutes, and when the LCP film was used, the heat treatment condition was 300° C. for 30 minutes.

Comparative Examples 1-5
The surface activation treated polymer film, the alkaline solution (treatment chemical solution) and the inorganic substrate were changed, and the same operation as in Example 1 was carried out to obtain a laminate. The obtained laminated body was evaluated in the same manner as in Example 1. The results are shown in Table 3. When the PEN film was used, the heat treatment condition was 250° C. for 30 minutes, and when the LCP film was used, the heat treatment condition was 300° C. for 30 minutes.

Application Example Each of the laminates obtained in Examples 1 to 20 was fixed to a substrate holder in a sputtering apparatus by covering a stainless steel frame having an opening. Fix the substrate holder and the support surface so that they are in close contact with each other. Therefore, the temperature of the film can be set by flowing the cooling medium into the substrate holder. The substrate temperature was set to 2°C. Then, the plasma treatment of the film surface was performed. The plasma treatment conditions were a condition of a frequency of 13.56 MHz, an output of 200 W, and a gas pressure of 1×10 ⁻³ Torr in argon gas, the temperature during the treatment was 2° C., and the treatment time was 2 minutes. Then, a frequency of 13.56 MHz, an output of 450 W, a gas pressure of 3×10 ⁻³ Torr, a nickel-chromium (chromium 10% by mass) alloy target, and a DC magnetron sputtering method in an argon atmosphere at 1 nm/sec. A nickel-chromium alloy film (underlayer) having a thickness of 11 nm is formed at a rate of, and then the back surface of the sputter surface of the substrate is temperature-controlled to 3° C. so that the temperature of the substrate is set to 2° C. Sputtering was performed in a state of being in contact with the SUS plate of the substrate holder that had flowed. Copper was vapor-deposited at a rate of 10 nm/sec to form a copper thin film having a thickness of 0.22 μm. A base metal thin film-forming film was obtained from each film. The thickness of the copper and NiCr layers was confirmed by the fluorescent X-ray method.

Then, the laminated plate with the underlying metal thin film forming film from each film was fixed to a Cu frame, and a thick copper layer was formed using a copper sulfate plating bath. The electrolytic plating conditions were immersion in an electrolytic plating solution (copper sulfate 80 g/l, sulfuric acid 210 g/l, HCl, a small amount of a brightener), and an electric current of 1.5 A/dm ² was applied. Thereby, a thick copper plating layer (thick layer) having a thickness of 4 μm was formed and subsequently heat-treated and dried at 120° C. for 10 minutes to obtain a metallized polymer film/glass laminate.

Using each of the obtained metallized polymer films/glass laminates, a photoresist: FR-200, manufactured by Shipley Co., Ltd. was applied and dried, and then contact exposure was carried out with a glass photomask, and further 1.2% by mass KOH aqueous solution was used. Developed. Then, after etching with a cupric chloride etching line containing HCl and hydrogen peroxide at a spray pressure of ² kgf/cm ² at 40° C., a line array of line/space=20 μm/20 μm was formed as a test pattern. Electroless tin plating was performed to a thickness of 0.5 μm. After that, annealing treatment was performed at 125° C. for 1 hour. The dripping of the test pattern, the remaining pattern, and the peeling of the pattern were observed with an optical microscope.

Good test patterns were obtained in which the polymer film/inorganic substrate laminates of Examples 1 to 20 did not sag and the pattern remained and the pattern did not peel off.
Further, the temperature rising rate was 10 in a muffle furnace in which the polymer film/inorganic substrate laminates obtained in Examples 1 to 3, Examples 6 to 8, Examples 11 to 13 and Examples 16 to 18 were replaced with nitrogen. Even if the temperature was raised to 400° C. at a rate of° C./min, the temperature was kept at 400° C. for 1 hour, and then the temperature was naturally lowered, no swelling or peeling occurred.
On the other hand, in all of the polymer film/inorganic substrate laminates of Comparative Examples 1 to 5, film peeling occurred, and no good test pattern was obtained.

According to the method for manufacturing a flexible electronic device of the present invention, it is possible to temporarily fix a polymer film that has been subjected to a surface activation treatment to an inorganic substrate for bonding (temporary support) without using a vacuum device. In particular, the contribution to the industry is extremely large as a temporary fixing technology when manufacturing a flexible electronic device.

Claims (6)

Bonding a polymer film on an inorganic substrate, in the manufacturing method of a flexible electronic device for peeling the polymer film from the inorganic substrate after forming an electronic device on a polymer film, bonded to at least the inorganic substrate polymer The surface of the film is surface-activated with an alkaline solution containing oxyalkylamine, and the surface of the inorganic substrate to be bonded to the polymer film is untreated with a silane coupling agent. A method for manufacturing a flexible electronic device, wherein the film is temporarily fixed. The method for manufacturing a flexible electronic device according to claim 1, wherein the oxyalkylamine is one or more selected from the group consisting of monooxymonoamine and monoaminopolyhydric alcohol. Method of manufacturing a flexible electronic device according to claim 1 or 2 polymer film is a polymer film of condensation. The polymer film is a polyimide film, method of manufacturing a flexible electronic device according to any one of claims 1 to 3, which is a polyethylene naphthalate film or a liquid crystal polymer film. The bonding of the inorganic substrate and the polymer film, and no machine board, flexible electronic according to any one of claims 1 to 4, and a polymer film treated surface activation is performed by heating and pressurizing Device manufacturing method. Method of manufacturing a flexible electronic device according to any one of claims 1 to 5 without the use of a vacuum apparatus at the surface activation and the polymer film and heating and pressurizing the inorganic substrate of the polymer film.