TW202327872A - Protective film-equipped laminate of inorganic substrate and heat-resistant polymer film - Google Patents

Abstract

Provided are: a laminate in which it is possible to peel the protective film from a protective film-equipped laminate of a heat-resistant polymer film and an inorganic substrate without peeling off the heat-resistant polymer film or inorganic substrate; and a method for manufacturing the laminate. The laminate comprises a protective film, a heat-resistant polymer film, and an inorganic substrate, in that order, and is characterized in that the peel strength F1 according to a 90 DEG peeling test of the inorganic substrate and the heat-resistant polymer film, the angle [Theta] formed by the protective film and the heat-resistant polymer film when the protective film is peeled from the heat-resistant polymer film, the tensile force T applied to the protective film, and the elastic modulus E of the protective film satisfy (1) Tsin[Theta] < F1 and (2) E > 2GPa.

Description

Laminate of inorganic substrate with protective film and heat-resistant polymer film

The present invention relates to a laminate of an inorganic substrate with a protective film and a heat-resistant polymer film.

As substrate materials for the manufacture of flexible electronic devices, heat-resistant polymer films such as polyimide have been examined. Such a polymer film such as polyimide is produced in a long roll, so it is generally considered that a roll-to-roll production line is more suitable for the production of flexible devices. ideal. On the other hand, in the past, electronic devices such as display devices, sensor arrays, touch screens, and printed wiring boards mostly used hard rigid substrates such as glass substrates, semiconductor wafers, or glass fiber-reinforced epoxy substrates. Regarding manufacturing equipment It is also constructed on the premise of using such a rigid substrate.

Based on such a background, as a method of manufacturing a flexible electronic device using an existing manufacturing device, a method of manufacturing a flexible electronic device by using a rigid inorganic substrate such as a glass substrate as a temporary support is known. , processing in the state where the polymer film is attached to the temporary support, and after processing the electronic device on the polymer film, the polymer film on which the electronic device is formed is peeled off from the temporary support (Patent Document 1).

In addition, as a method of manufacturing flexible electronic devices using existing manufacturing equipment, it is known to use a rigid substrate such as a glass substrate as a temporary support, apply a polymer solution or a polymer precursor solution to the temporary support, and perform After drying to form a precursor film, a chemical reaction is caused to convert the precursor into a polymer film, thereby obtaining a laminate of a temporary support and a polymer film, and then peeling off after forming an electronic device on the polymer film in the same manner. A method for manufacturing flexible electronic devices (Patent Document 2).

However, in the process of forming desired functional elements on a laminate bonded with a support made of a polymer film and an inorganic substance, the laminate is often exposed to high temperatures. For example, in the formation of functional devices such as polysilicon and oxide semiconductors, steps in the temperature range of about 200° C. to 600° C. are required. In addition, in the production of hydrogenated amorphous silicon thin film, there are cases where a temperature of about 200-300°C is applied to the thin film, and in order to heat and dehydrogenate amorphous silicon to become low-temperature polysilicon, it is necessary to use about 450°C-600°C the heating situation. Therefore, heat resistance is required for the polymer film constituting the laminate, but the practical problem is that there are limited practical polymer films that can withstand such a high temperature range, and polyimide is selected in many cases.

That is, in either method, a laminate in the form of laminating a rigid temporary support and a heat-resistant polymer film is passed, and the heat-resistant polymer film is finally peeled off to become a base material of a flexible electronic device. Since this laminate can be handled as a rigid plate, it can be handled in the same way as a glass substrate by conventional equipment used to manufacture liquid crystal displays, plasma displays, or organic EL displays using glass substrates.

Conventional rigid inorganic substrates such as glass substrates have been handled in stacks in which a plurality of sheets are stacked during storage or transportation. When stacking, a buffer material such as a foamed polymer sheet or paper is interposed between the inorganic substrates so that the inorganic substrates can be easily taken out from the stack after storage or transportation. This method can be applied to glass substrates with sufficient surface hardness, but in the laminated body of the inorganic substrate (temporary support substrate) and heat-resistant polymer film used in the present invention, since the hardness of the surface of the heat-resistant polymer film is insufficient, if the When the laminates are stacked, the surface of the heat-resistant polymer film of the laminate rubs against the surface of the inorganic substrate, and scratches are introduced on the surface of the soft heat-resistant polymer film. Furthermore, even when a cushioning material such as a foamed polymer sheet or paper is placed, scratches are likely to be generated on the surface of the heat-resistant polymer film due to foreign substances mixed therein.

As a means to solve such a problem, the usual method is to protect the surface of the heat-resistant polymer film with a protective film. Generally speaking, the protective film is a microadhesive film in which a relatively inexpensive polymer film such as polyethylene, polypropylene, or polyester is coated with a weakly adhesive adhesive material on one side. Moreover, from the viewpoint of cost reduction, a self-adsorbing resin film such as polyolefin-based resin may be used.

By using this protective film, damage to the surface of the heat-resistant polymer film can be prevented, and the surface of the polymer film suitable for forming fine flexible electronic devices can be maintained. Moreover, similarly to the glass substrate, a cushioning material such as a foamed polymer sheet or paper may be used in combination. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Invention Patent No. 5152104 [Patent Document 2] Japanese Invention Patent No. 5699606

[Problem to be solved by the invention]

However, in the aforementioned method, an auxiliary material is used in addition to the protective film, which increases the cost and increases waste, so the use of a cushioning material cannot be said to be a preferable method. In addition, when a polymer solution or a polymer precursor solution (hereinafter also referred to as a polymer solution) is coated on an inorganic substrate to convert it into a polymer film to manufacture a laminate, the laminate manufacturing step becomes a batch process, but In consideration of productivity in subsequent steps, it is preferably in the form of a continuous sheet to which a single-sheet laminate is bonded. From the perspective of preventing damage to the heat-resistant polymer film surface and the inorganic substrate and improving the handling property, as shown in Figure 1, a long protective film can be continuously attached to the heat-resistant polymer film surface of the laminate, and the single sheet The laminate is handled as a continuous sheet. In this case, storage and transportation may be performed in a stacked state of folded protective films as shown in FIGS. 2 and 3 .

The present inventors faced the problem that when peeling the protective film from such a continuous sheet, it is difficult to peel the protective film from the heat-resistant polymer film without peeling the inorganic substrate and the heat-resistant polymer film. The laminate of the heat-resistant polymer film with protective film and the inorganic substrate (hereinafter also referred to as the laminate) of the present invention is intended to be peeled off from the inorganic substrate after the device is finally fabricated on the surface of the heat-resistant polymer film. Power is stacked. Also, when the protective film is peeled off from the monolithic laminate, at the starting point of the peeling of the protective film, the surface of the protective film is mostly raised. In theory, as long as the peel strength of the heat-resistant polymer film and the protective film is lower than that of the inorganic substrate The peel strength of the heat-resistant polymer film can be selected as the protective film, but in fact, it is known that if the peel strength of the heat-resistant polymer film and the protective film is more than 1/3 of the bonding strength between the inorganic substrate and the heat-resistant polymer film, it is difficult. Peel off only the protective film.

The problem to be solved by the present invention is to provide a laminate of a heat-resistant polymer film with a protective film and an inorganic substrate (rigid temporary support), and the protective film can be peeled off without peeling off the heat-resistant polymer film and the inorganic substrate. Laminate with heat-resistant polymer film and method thereof. [Means to solve the problem]

That is, the present invention includes the following configurations. [1] A laminate, which is a laminate sequentially comprising a protective film, a heat-resistant polymer film, and an inorganic substrate, characterized in that: The peel strength F1 of the 90° peel test of the aforementioned inorganic substrate and the aforementioned heat-resistant polymer film, The angle θ formed by the aforementioned protective film and the aforementioned heat-resistant polymer film when the aforementioned protective film is peeled off from the aforementioned heat-resistant polymer film, Tension T applied to the aforementioned protective film, and The elastic modulus E of aforementioned protective film is Tsinθ＜F1 (1) and E＞2GPa (2). [2] The laminate according to [1], wherein the aforementioned F1 is in the range of 0.02 to 0.3 N/cm. [3] The laminate according to [1] or [2], wherein the peel strength of the protective film and the heat-resistant polymer film in a 90° peel test is (1/3)×F1 or more. [4] The laminate according to any one of [1] to [3], wherein the aforementioned θ is 30° or less. [5] The laminate according to any one of [1] to [4], wherein 0.2≦ETsinθ≦4 is satisfied. [6] A peeling method, which is a method of peeling the aforementioned protective film from a laminate sequentially comprising a protective film, a heat-resistant polymer film, and an inorganic substrate, characterized in that: The peel strength F1 of the 90° peel test of the aforementioned inorganic substrate and the aforementioned heat-resistant polymer film, The angle θ formed by the aforementioned protective film and the aforementioned heat-resistant polymer film when the aforementioned protective film is peeled off from the aforementioned heat-resistant polymer film, Tension T applied to the aforementioned protective film, and The elastic modulus E of aforementioned protective film is Tsinθ＜F1 (1) and E＞2GPa (2). [7] The peeling method according to [6], comprising a roller for assisting peeling of the protective film. [Effect of Invention]

In a laminate of a heat-resistant polymer film with a protective film and an inorganic substrate (rigid temporary support), when the peel strength of the heat-resistant polymer film and the protective film is 1/3 or more of the inorganic substrate and the heat-resistant polymer film, it is difficult to Peel off only the protective film. In particular, when the peel strength between the inorganic substrate and the heat-resistant polymer film is low, the inorganic substrate and the heat-resistant polymer film are peeled off when the end of the protective film is lifted. If the size of the laminate is small, since the tape can be peeled off using the protective film, the peeling end can be made manually, and only the end of the protective film can be peeled off with a jig such as tweezers, so there is no major problem. However, if it is assumed that it is processed in a display manufacturing device, the inorganic substrate The size of the laminate with heat-resistant polymer film is about 2×3m at most. In a laminate of such a size, the peeling of the protective film is supposed to be carried out mechanically. For example, in the case of manual peeling, it is difficult to peel only the protective film without peeling off the inorganic substrate and the heat-resistant polymer film with delicate addition and subtraction forces. By adopting the constitution of the present invention, such problems can be avoided, and the lamination system of the present invention can peel off only the protective film without peeling off the inorganic substrate and the heat-resistant polymer film even in the case of manual or automatic.

[Mode for Carrying Out the Invention]

Hereinafter, one embodiment of the present invention (hereinafter referred to as "embodiment") will be described in detail. In addition, this invention is not limited to the following embodiment, Various deformation|transformation can be implemented within the scope of the gist.

＜Heat-resistant polymer film＞ The heat-resistant polymer film of the present invention (hereinafter also referred to simply as the polymer film) is a layer comprising a heat-resistant polymer film, which is heated to volatilize the solvent of the polymer solution, or is cured by heating the polymer precursor solution to volatilize the solvent . The polymer solution includes, for example, soluble polyimide, and the polymer precursor solution includes, for example, a polyamic acid solution. The heat-resistant polymer film may be composed of a single layer or a multilayer (lamination) of two or more layers. When the heat-resistant polymer film is composed of multiple layers, the respective heat-resistant polymer films may have the same composition or different compositions. When the heat-resistant polymer film has a single-layer structure, the physical properties of the heat-resistant polymer film (melting point, glass transition temperature, yellowness index, total light transmittance, haze, CTE, etc.) refer to the value of the entire heat-resistant polymer film. When the heat-resistant polymer film has a multilayer structure, the physical properties of the heat-resistant polymer film refer to the value of the entire heat-resistant polymer film.

Examples of heat-resistant polymer films include polyimide-based resins such as polyimide, polyamideimide, polyetherimide, and fluorinated polyimide (for example, aromatic polyimide resin, alicyclic polyimide resin); copolymerization of polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene 2,6-naphthalene dicarboxylate, etc. Esters (such as fully aromatic polyesters, semi-aromatic polyesters); copolymerized (meth)acrylates represented by polymethyl methacrylate; polycarbonate; polyamide; Polyether ketone; cellulose acetate; nitrocellulose; aromatic polyamide; polyvinyl chloride; polyphenol; polyarylate; polyphenylene sulfide; polyphenylene ether; polystyrene and other films. However, the above-mentioned polymer film is premised on being used in a process involving heat treatment at 300° C. or higher, and therefore, among the illustrated polymer films, the ones that are actually applicable are limited. Among the above-mentioned polymer films, it is preferable to use so-called super engineering plastic films, and more specifically, aromatic polyimide films, aromatic amide films, aromatic amide imide films, Aromatic polybenzo Azole film, aromatic benzothiazole film, aromatic benzimidazole film, etc. The heat-resistant polymer film preferably contains at least one type selected from the group consisting of polyimide, polyamide, and polyamideimide.

The details of a polyimide-based resin film (also referred to as a polyimide film) as an example of the aforementioned polymer film will be described below. Generally speaking, polyimide-based resin films are polyamic acid (polyimide precursor, also known as polyamic acid) obtained by reacting diamines and tetracarboxylic acids in a solvent. The solution is coated on a support for making a polyimide film, dried to form a green film, and then on a support for making a polyimide film, or in a state after being peeled off from the support, It is obtained by subjecting the green film to high-temperature heat treatment and performing dehydration and ring-closing reaction.

The polymer film of the present invention is preferably monolithic. Specifically, it is preferably a square or a rectangle, and the length of the long side is preferably at least 1 time, more preferably at least 2 times, and most preferably at least 3 times the length of the short side of the heat-resistant polymer film. Also, it is preferably at most 20 times, more preferably at most 15 times, and especially preferably at most 10 times. In addition, the radius of the circumscribed circle of the polymer film is preferably at least 330 mm, more preferably at least 350 mm, and most preferably at least 400 mm. In addition, industrially, it is enough to be 30000 mm or less, and 20000 mm or less is also fine.

＜Polyamide＞ The polyamic acid system in this invention can be manufactured by a well-known manufacturing method. That is, a polyamide acid solution is obtained by polymerizing in an organic solvent using one or more tetracarboxylic anhydride components and one or more diamine components as raw materials. The preferred solvent for the synthesis of polyamic acid is an amide solvent, that is, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, etc., especially the use of N,N- Dimethylacetamide. In the reaction device, it is preferable to have a temperature adjustment device for controlling the reaction temperature. The reaction temperature is preferably from 0°C to 80°C, more preferably from 15°C to 60°C. Polyamide that inhibits the reverse reaction of polymerization The hydrolysis of amino acid, and the viscosity of polyamic acid is easy to rise.

The diamines constituting the polyamic acid are not particularly limited, and aromatic diamines, aliphatic diamines, alicyclic diamines, and the like generally used in polyimide synthesis can be used. From the viewpoint of heat resistance, aromatic diamines are preferred. Diamines may be used alone or in combination of two or more.

It does not specifically limit as diamines, For example, oxydiphenylamine (bis(4-aminophenyl)ether), p-phenylenediamine (1,4-phenylenediamine), etc. are mentioned.

As tetracarboxylic acids constituting polyamic acid, aromatic tetracarboxylic acids (including their anhydrides), aliphatic tetracarboxylic acids (including their anhydrides), and alicyclic tetracarboxylic acids commonly used in the synthesis of polyimides can be used. (including its anhydride). When these are acid anhydrides, one or two anhydride structures may be used in the molecule, and those having two anhydride structures (dianhydride) are preferred. Tetracarboxylic acids may be used alone or in combination of two or more.

The tetracarboxylic acid is not particularly limited, and examples thereof include pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, and the like.

The thermally cured product of polyamide acid is preferably polyimide, and may also be colorless and transparent polyimide.

A colorless and transparent polyimide which is an example of a thermosetting product of polyamide acid in the present invention will be described. In order to avoid complexity, it is only described as transparent polyimide below. The transparency of the transparent polyimide is preferably above 75%, more preferably above 80%, especially above 85%, especially preferably above 87%, and most preferably above 88%. The upper limit of the total light transmittance of the aforementioned transparent polyimide is not particularly limited, but in order to be used as a flexible electronic device, it is preferably less than 98%, more preferably less than 97%. The colorless and transparent polyimide in the present invention is preferably a polyimide with a total light transmittance of 75% or more.

The aromatic tetracarboxylic acids used to obtain the colorless and highly transparent polyimide in the present invention may be used alone or in combination of two or more. The amount of copolymerization of aromatic tetracarboxylic acids is, for example, preferably at least 50% by mass, more preferably at least 60% by mass, particularly preferably at least 70% by mass, and even more preferably 80% by mass or more, especially preferably 90% by mass or more, and 100% by mass is fine.

Examples of the aromatic tetracarboxylic acids used to obtain the colorless and highly transparent polyimide in the present invention include 4,4'-(2,2-hexafluoroisopropylidene)diphthalic acid, 4,4'-Oxydiphthalic acid, bis(1,3-dioxy-1,3-dihydro-2-benzofuran-5-carboxylic acid) 1,4-phenylene ester, bis( 1,3-Dioxo-1,3-dihydro-2-benzofuran-5-yl)benzene-1,4-dicarboxylate, 4,4'-[4,4'-(3- Oxygen-1,3-dihydro-2-benzofuran-1,1-diyl)bis(benzene-1,4-diyloxy)]diphenyl-1,2-dicarboxylic acid, 3,3 ',4,4'-benzophenone tetracarboxylic acid, 4,4'-[(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl)bis(toluene- 2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[(3-oxo-1,3-dihydro-2-benzofuran-1,1-di Base) bis(1,4-xylene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[4,4'-(3-oxo-1, 3-dihydro-2-benzofuran-1,1-diyl)bis(4-ylpropyl-toluene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4, 4'-[4,4'-(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl)bis(naphthalene-1,4-diyloxy)]bis Benzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benzo Thiol-1,1-dioxide-3,3-diyl)bis(benzene-1,4-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-diphenylmethane Ketotetracarboxylic acid, 4,4'-[(3H-2,1-benzo Thiol-1,1-dioxide-3,3-diyl)bis(toluene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[(3H -2,1-Benzo Thiol-1,1-dioxide-3,3-diyl)bis(1,4-xylene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4 '-[4,4'-(3H-2,1-benzo Thiol-1,1-dioxide-3,3-diyl)bis(4-isopropyl-toluene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4, 4'-[4,4'-(3H-2,1-benzo Thiol-1,1-dioxide-3,3-diyl)bis(naphthalene-1,4-diyloxy)]diphenyl-1,2-dicarboxylic acid, 3,3',4,4 '-Benzophenone tetracarboxylic acid, 3,3',4,4'-benzophenone tetracarboxylic acid, 3,3',4,4'-diphenylphenone tetracarboxylic acid, 3,3',4, 4'-Biphenyltetracarboxylic acid, 2,3,3',4'-Biphenyltetracarboxylic acid, pyromellitic acid, 4,4'-[spiro(xaton-9,9'-oxene)-2 ,6-Diylbis(oxycarbonyl)]diphthalic acid, 4,4'-[spiro(xaton-9,9'-oxaline)-3,6-diylbis(oxycarbonyl)] Tetracarboxylic acids such as diphthalic acid and their anhydrides. Among these, dianhydrides having two acid anhydride structures are preferred, and 4,4'-(2,2-hexafluoroisopropylidene)diphthalic dianhydride, 4,4' -Oxydiphthalic dianhydride. Furthermore, the aromatic tetracarboxylic acids may be used alone or in combination of two or more. The amount of copolymerization of aromatic tetracarboxylic acids is, for example, preferably at least 50% by mass of all tetracarboxylic acids, more preferably at least 60% by mass, especially preferably at least 70% by mass, even more preferably at least 70% by mass, when emphasis is placed on heat resistance 80% by mass or more, especially preferably 90% by mass or more, and 100% by mass is fine.

Examples of alicyclic tetracarboxylic acids include 1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cyclopentane tetracarboxylic acid, 1,2,3,4-cyclohexane Tetracarboxylic acid, 1,2,4,5-cyclohexane tetracarboxylic acid, 3,3',4,4'-bicyclohexyl tetracarboxylic acid, bicyclo[2,2,1]heptane-2,3,5,6 -tetracarboxylic acid, bicyclo[2,2,2]octane-2,3,5,6-tetracarboxylic acid, bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic acid , Tetrahydroanthracene-2,3,6,7-tetracarboxylic acid, Tetrahydro-1,4:5,8:9,10-tri-bridge methylene anthracene-2,3,6,7-tetracarboxylic acid, Tetrahydroanthracene-2,3,6,7-tetracarboxylic acid Hydronaphthalene-2,3,6,7-tetracarboxylic acid, Tetrahydro-1,4:5,8-Dioxomethylenenaphthalene-2,3,6,7-tetracarboxylic acid, Tetrahydro-1,4- Ethylene-5,8-methylenenaphthalene-2,3,6,7-tetracarboxylic acid, norbornane-2-spiro-α-cyclopentanone-α'-spiro-2”-norbornane Alkane-5,5",6,6"-tetracarboxylic acid (alias "norbornane-2-spiro-2'-cyclopentanone-5'-spiro-2"-norbornane-5,5",6 ,6”-tetracarboxylic acid”), Methylnorbornane-2-spiro-α-cyclopentanone-α’-spiro-2”-(methylnorbornane)-5,5”,6,6” -Tetracarboxylic acid, norbornane-2-spiro-α-cyclohexanone-α'-spiro-2”-norbornane-5,5”,6,6”-tetracarboxylic acid (alias “norbornane-2 -spiro-2'-cyclohexanone-6'-spiro-2"-norbornane-5,5",6,6"-tetracarboxylic acid"), methylnorbornane-2-spiro-α-ring Hexanone-α'-spiro-2"-(methylnorbornane)-5,5",6,6"-tetracarboxylic acid, norbornane-2-spiro-α-cyclopropanone-α'-spiro- 2”-Norbornane-5,5”,6,6”-tetracarboxylic acid, norbornane-2-spiro-α-cyclobutanone-α’-spiro-2”-norbornane-5,5” ,6,6”-tetracarboxylic acid, norbornane-2-spiro-α-cycloheptanone-α’-spiro-2”-norbornane-5,5”,6,6”-tetracarboxylic acid, norbornane Alkane-2-spiro-α-cyclooctanone-α'-spiro-2”-norbornane-5,5”,6,6”-tetracarboxylic acid, norbornane-2-spiro-α-cyclononone -α'-spiro-2"-norbornane-5,5",6,6"-tetracarboxylic acid, norbornane-2-spiro-α-cyclodecanone-α'-spiro-2"-norbornane Alkane-5,5",6,6"-tetracarboxylic acid, norbornane-2-spiro-α-cycloundecanone-α'-spiro-2"-norbornane-5,5",6,6 "-tetracarboxylic acid, norbornane-2-spiro-α-cyclododecanone-α'-spiro-2"-norbornane-5,5",6,6"-tetracarboxylic acid, norbornane-2 -Spiro-α-cyclotridecanone-α'-spiro-2”-norbornane-5,5”,6,6”-tetracarboxylic acid, norbornane-2-spiro-α-cyclotetradecone- α'-spiro-2"-norbornane-5,5",6,6"-tetracarboxylic acid, norbornane-2-spiro-α-cyclopentadecone-α'-spiro-2"-norbornane Alkane-5,5”,6,6”-tetracarboxylic acid, norbornane-2-spiro-α-(methylcyclopentanone)-α’-spiro-2”-norbornane-5,5”, 6,6"-tetracarboxylic acid, norbornane-2-spiro-α-(methylcyclohexanone)-α'-spiro-2"-norbornane-5,5",6,6"-tetracarboxylic acid Tetracarboxylic acids and their anhydrides, or 5,5-(1,4-phenylene)-endo-bis(hexahydro-4,7-methanoisobenzofuran-cis-endo -1,3-diketone) etc. Among them, dianhydrides having two acid anhydride structures are preferable, and 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2,3,4-cyclohexanetetracarboxylic acid are particularly preferable. Dianhydride, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, more preferably 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,4,5-cyclohexane tetra Formic dianhydride is particularly preferably 1,2,3,4-cyclobutanetetracarboxylic dianhydride. In addition, these may be used individually, and may use 2 or more types together. The copolymerization amount of alicyclic tetracarboxylic acids is, for example, preferably at least 50% by mass of all tetracarboxylic acids, more preferably at least 60% by mass, particularly preferably at least 70% by mass, and even more preferably when transparency is important. It is 80% by mass or more, especially preferably 90% by mass or more, and 100% by mass is fine.

Examples of tricarboxylic acids include trimellitic acid, 1,2,5-naphthalenetricarboxylic acid, diphenyl ether-3,3',4'-tricarboxylic acid, diphenylsulfone-3,3',4 Aromatic tricarboxylic acids such as '-tricarboxylic acid, or hydrogenated products of the above-mentioned aromatic tricarboxylic acids such as hexahydrotrimellitic acid, ethylene glycol bis-trimellitic acid ester, propylene glycol bis-trimellitic acid ester, 1 , 4-butanediol bis-trimellitic acid ester, polyethylene glycol bis-trimellitic acid ester and other alkanediol bis-trimellitic acid esters, and their anhydrides and esterified products. Among them, a monoanhydride having one acid anhydride structure is preferable, and trimellitic anhydride and hexahydrotrimellitic anhydride are particularly preferable. In addition, these may be used individually, and may be used combining plural ones.

Examples of dicarboxylic acids include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, naphthalene dicarboxylic acid, and 4,4'-oxydibenzoic acid, or 1,6- Hydrogenated aromatic dicarboxylic acids such as cyclohexanedicarboxylic acid, oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecane dicarboxylic acid, etc. acid, dodecanedioic acid, 2-methylsuccinic acid, and their acyl chlorides or esters, etc. Among them, aromatic dicarboxylic acids and their hydrogenated products are preferable, and terephthalic acid, 1,6-cyclohexanedicarboxylic acid, and 4,4'-oxydibenzoic acid are particularly preferable. Furthermore, dicarboxylic acids may be used alone or in combination of a plurality of them.

The diamines or isocyanates for obtaining the colorless and highly transparent polyimide in the present invention are not particularly limited, and polyimide synthesis, polyamide imide synthesis, polyamide synthesis, and polyamide synthesis can be used. Aromatic diamines, aliphatic diamines, alicyclic diamines, aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, etc. commonly used in From the viewpoint of heat resistance, aromatic diamines are preferred, and from the viewpoint of transparency, alicyclic diamines are preferred. Also, if using a benzo Aromatic diamines with an azole structure can exhibit high heat resistance, high elastic modulus, low thermal shrinkage, and low linear expansion coefficient. Diamines and isocyanates may be used alone or in combination of two or more.

Examples of aromatic diamines include 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,4-bis[2-(4-aminophenyl)-2- Propyl]benzene, 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, 2,2'-bistrifluoromethyl-4,4'-diaminobiphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)benzene Base] ketone, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-(3-aminophenoxy)phenyl]pyridine, 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, 4-amino-N-(4-aminophenyl)benzamide, 3 ,3'-Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2'-trifluoromethyl-4, 4'-Diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl Thioethers, 3,3'-diaminodiphenylene, 3,4'-diaminodiphenylene, 4,4'-diaminodiphenylene, 3,3'- Diaminodiphenylphenone, 3,4'-diaminodiphenylphenone, 4,4'-diaminodiphenylphenone, 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-amino Phenoxy)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- Aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ketone, bis[4-(4 -aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy)phenyl]pyridine, bis[4-(4-aminophenoxy)phenyl]pyridine, Bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether, 1,3-bis[4-(4-aminophenoxy) Oxy)benzoyl]benzene, 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy ) 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) Oxy)phenyl]pyridine, 4,4'-bis[3-(4-aminophenoxy)benzoyl]diphenyl ether, 4,4'-bis[3-(3-amine phenoxy)benzoyl]diphenyl ether, 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzophenone, 4 ,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylphenoxide, bis[4-{4-(4-aminophenoxy)benzene Oxy}phenyl]pyridine, 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 base)-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-phenoxydiphenyl Methanone, 4,4'-diamino-5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3,4'-diamino- 5'-phenoxybenzophenone, 3,3'-diamino-4,4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-di Biphenoxybenzophenone, 3,4'-diamino-4,5'-diphenoxybenzophenone, 3,3'-diamino-4-biphenoxydiphenyl Methanone, 4,4'-diamino-5-biphenoxybenzophenone, 3,4'-diamino-4-biphenoxybenzophenone, 3,4'-diamine Base-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-phenoxybenzene Formyl)benzene, 1,3-bis(3-amino-4-biphenoxybenzoyl)benzene, 1,4-bis(3-amino-4-biphenoxybenzoyl) base) 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, 4,4'-[9H-fennel-9,9-diyl ]Bisaniline (alias "9,9-bis(4-aminophenyl) oxane"), spiro(xaton-9,9'-oxo)-2,6-diylbis(oxycarbonyl)]bis Aniline, 4,4'-[spiro(xaton-9,9'-oxene)-2,6-diylbis(oxycarbonyl)]bisaniline, 4,4'-[spiro(xaton-9, 9'-Oxyl)-3,6-diylbis(oxycarbonyl)]bisaniline, etc. Also, part or all of the hydrogen atoms on the aromatic ring of the above-mentioned aromatic diamine may be substituted by a halogen atom, an alkyl or alkoxy group or a cyano group with 1 to 3 carbons, and the aforementioned hydrogen atoms with 1 to 3 carbons Part or all of the hydrogen atoms in the alkyl or alkoxy group may be substituted by halogen atoms. Also, as having the aforementioned benzo Aromatic diamines with an azole structure are not particularly limited, for example, 5-amino-2-(p-aminophenyl)benzo Azole, 6-amino-2-(p-aminophenyl)benzo Azole, 5-amino-2-(m-aminophenyl)benzo Azole, 6-amino-2-(m-aminophenyl)benzo Azole, 2,2'-p-phenylene bis(5-aminobenzo azole), 2,2'-p-phenylene bis(6-aminobenzo azole), 1-(5-aminobenzo Azolone)-4-(6-aminobenzo Azolone)benzene, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:5,4-d']bis Azole, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bis Azole, 2,6-(3,4'-diaminodiphenyl)benzo[1,2-d:5,4-d']bis Azole, 2,6-(3,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bis Azole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:5,4-d']bis Azole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:4,5-d']bis azole etc. Among these, 2,2'-bistrifluoromethyl-4,4'-diaminobiphenyl, 4-amino-N-(4-aminophenyl)benzamide are particularly preferred , 4,4'-diaminodiphenylphenone, 3,3'-diaminobenzophenone. Furthermore, the aromatic diamines may be used alone or in combination of a plurality of them.

Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-2-ethane Cyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-propylcyclohexane, 1,4-diamino-2-n- Butylcyclohexane, 1,4-diamino-2-ylbutylcyclohexane, 1,4-diamino-2-second butylcyclohexane, 1,4-diamino-2 - tert-butylcyclohexane, 4,4'-methylenebis(2,6-dimethylcyclohexylamine) and the like. Among these, 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane are particularly preferred, and 1,4-diaminocyclohexane is more preferred . Furthermore, the alicyclic diamines may be used alone or in combination of a plurality of them.

Examples of diisocyanates include diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- or 5,2' - or 5,3'- or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2 '- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3, 2'- or 3,3'- or 4,2'- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethoxydi Phenylmethane-2,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-3,3'-diisocyanate, diphenylmethane-3,4'-diisocyanate , diphenylether-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, diphenylene-4,4'-diisocyanate, toluene-2,4-diisocyanate, toluene -2,6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4'-(2,2 bis(4-phenoxybenzene base) propane) diisocyanate, 3,3'- or 2,2'-dimethylbiphenyl-4,4'-diisocyanate, 3,3'- or 2,2'-diethylbiphenyl -4,4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 3,3'-diethoxybiphenyl-4,4'-diisocyanate Aromatic diisocyanates, and hydrogenated diisocyanates of any of these (such as isophorone diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 4 , 4'-Dicyclohexylmethane diisocyanate, hexamethylene diisocyanate) etc. Among these, diphenylmethane-4,4'-diisocyanate, toluene-2,4-diisocyanate, Toluene-2,6-diisocyanate, 3,3'-dimethylbiphenyl-4,4'-diisocyanate or naphthalene-2,6-diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-Cyclohexane diisocyanate. Furthermore, diisocyanates may be used alone or in combination of a plurality of them.

The average coefficient of linear expansion (CTE) of the heat-resistant polymer film between 30°C and 250°C is preferably below 50ppm/K, more preferably below 45ppm/K, especially preferably below 40ppm/K, even more preferably below 30ppm/K Below K, especially preferably below 20ppm/K. Also, it is preferably at least -5 ppm/K, more preferably at least -3 ppm/K, and most preferably at least 1 ppm/K. If the CTE is within the aforementioned range, the difference in the coefficient of linear expansion from the general support (inorganic substrate) can be kept small, and the heat-resistant polymer film can be prevented from being peeled off from the inorganic substrate or warped together with the support even when heating is applied. . The so-called CTE here refers to the factor of expansion and contraction reversible with respect to temperature. Furthermore, the CTE of the aforementioned heat-resistant polymer film refers to the average value of the CTE in the coating direction (MD direction) of the polymer solution or the polymer precursor solution and the CTE in the width direction (TD direction).

The aforementioned heat-resistant polymer film is preferably a polyimide film, and may also be a transparent polyimide film. The aforementioned heat-resistant polymer film is a transparent polyimide film (hereinafter also referred to as a transparent heat-resistant polymer film), and its yellowness index (hereinafter also referred to as "yellow index" or "YI") is preferably less than 10, more preferably It is 7 or less, more preferably 5 or less, even more preferably 3 or less. The lower limit of the yellowness index of the aforementioned transparent polyimide is not particularly limited, but for use as a flexible electronic device, it is preferably above 0.1, more preferably above 0.2, and most preferably above 0.3.

The light transmittance of the transparent heat-resistant polymer film in the present invention at a wavelength of 400nm is preferably above 70%, more preferably above 72%, especially preferably above 75%, and even more preferably above 80%. The upper limit of the light transmittance of the above-mentioned transparent heat-resistant polymer film at a wavelength of 400nm is not particularly limited, but in order to be used as a flexible electronic device, it is preferably below 99%, more preferably below 98%, and especially preferably below 97%. %the following.

The haze of the transparent heat-resistant polymer film in the present invention is preferably 1.0 or less, more preferably 0.8 or less, especially preferably 0.5 or less, and still more preferably 0.3 or less. The lower limit is not particularly limited, but industrially there is no problem as long as it is 0.01 or more, and 0.05 or more is also fine.

The melting point of the heat-resistant polymer film is preferably above 250°C, more preferably above 300°C, and most preferably above 400°C. Also, the glass transition temperature is preferably at least 200°C, more preferably at least 320°C, and most preferably at least 380°C. In the present specification, melting point and glass transition temperature are obtained by differential thermal analysis (DSC). Furthermore, when the melting point exceeds 500° C., whether or not the melting point has been reached can be judged by visually observing the thermal deformation behavior when heating at that temperature.

The thickness of the heat-resistant polymer film in the present invention is preferably at least 5 μm, more preferably at least 8 μm, especially preferably at least 15 μm, and even more preferably at least 20 μm. The upper limit of the thickness of the heat-resistant polymer film is not particularly limited, but for use as a flexible electronic device, it is preferably less than 200 μm, more preferably less than 150 μm, and most preferably less than 90 μm. If it is too thin, handling after device formation will become difficult, and if it is too thick, flexibility will be impaired.

The thickness variation of the aforementioned heat-resistant polymer film is preferably less than 20%, more preferably less than 12%, especially preferably less than 7%, and most preferably less than 4%. When the thickness unevenness exceeds 20%, it tends to be difficult to apply to narrow parts. Also, the thickness of the heat-resistant polymer film is not uniform. For example, after peeling the heat-resistant polymer film from the inorganic substrate, the position of the heat-resistant polymer film at about 10 points can be intentionally extracted, and the heat-resistant polymer film can be measured with a contact film thickness meter. The thickness can be obtained from the following formula. Uneven thickness of heat-hardened polyamide (%) =100×(maximum thickness-minimum thickness)÷average thickness

In the heat-resistant polymer film, a reaction catalyst (imidization catalyst), inorganic fine particles, etc. may be contained as necessary. The aforementioned reaction catalysts, inorganic microparticles, etc. are preferably pre-added to the aforementioned polymer solution or polymer precursor solution as required.

As the imidization catalyst, it is preferable to use a tertiary amine. The tertiary amine is more preferably a heterocyclic tertiary amine. Specific preferred examples of heterocyclic tertiary amines include pyridine, 2,5-diethylpyridine, picoline, quinoline, and isoquinoline. The amount of the imidization agent is preferably 0.01-2.00 equivalents, particularly preferably 0.02-1.20 equivalents, to the reaction site of polyamic acid (polyimide precursor). When the amount of the imidization catalyst is less than 0.01 equivalent, a sufficient catalytic effect cannot be obtained, which is not preferable. When more than 2.00 equivalent, since the ratio of the catalyst which does not participate in a reaction increases, it is unfavorable in terms of cost.

Examples of the inorganic fine particles include inorganic oxide powders such as fine-grained silica (silica) powder and alumina powder, and inorganic salt powders such as fine-grained calcium carbonate powder and calcium phosphate powder. In the field of the present invention, since the coarse particles of these inorganic fine particles may cause defects in the next step, it is preferable that these inorganic fine particles are uniformly dispersed.

＜Inorganic substrate＞ As the above-mentioned inorganic substrate, as long as it is a plate-shaped one that can be used as a substrate made of inorganic substances, for example, those mainly composed of glass plates, ceramic plates, semiconductor wafers, metals, etc., and as such glass plates , ceramic plates, semiconductor wafers, metal composites, laminated ones, dispersed ones, fibers containing them, etc. In addition, the inorganic substrate in the present invention may be porous or nonwoven, for example, porous ceramics may be laminated on a glass plate, or metal fibers may be nonwoven.

The aforementioned glass plate includes quartz glass, high silicate glass (96% silica), soda lime glass, lead glass, aluminoborosilicate glass, borosilicate glass (Pyrex (registered trademark)), borosilicate glass (alkali-free), borosilicate glass (microflakes), aluminosilicate glass, etc. Among them, the coefficient of linear expansion should be 5ppm/K or less. If it is a commercially available product, it should be "Corning (registered trademark) 7059" or "Corning (registered trademark) 1737" manufactured by CORNING Co., Ltd., which is a glass for liquid crystals. , "EAGLE", "AN100" manufactured by Asahi Glass Co., Ltd., "OA10, OA11G" manufactured by Nippon Electric Glass Co., Ltd., "AF32" manufactured by SCHOTT Corporation, etc.

The aforementioned semiconductor wafer is not particularly limited, and examples include silicon wafers, germanium, silicon-germanium, gallium-arsenic, aluminum-gallium-indium, nitrogen-phosphorus-arsenic-antimony, SiC, and InP (indium-phosphorus) , InGaAs, GaInNAs, LT, LN, ZnO (zinc oxide) or CdTe (cadmium telluride), ZnSe (zinc selenide) and other wafers. Among them, the more suitable wafer is a silicon wafer, especially a mirror-polished silicon wafer with a size of 8 inches or more.

The aforementioned metals include single-element metals such as W, Mo, Pt, Fe, Ni, and Au, or Inconel, monel, nimonic, carbon copper, and Fe -Ni is an alloy of invar alloy, super-invar alloy, etc. In addition, these metals also include multilayer metal plates in which other metal layers and ceramic layers are added. At this time, if the coefficient of linear expansion (CTE) with the entire additional layer is low, Cu, Al, etc. may be 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 thermosetting polyamic acid, does not diffuse, and has good chemical resistance and heat resistance, but Cr , Ni, TiN, Mo-containing Cu, etc. are suitable examples.

The ceramic plate in the present invention includes Al ₂ O ₃ , mullite, AlN, SiC, 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-ceramics, glass-ceramics, etc. Ceramic substrates.

The thickness of the aforementioned inorganic substrate is not particularly limited, but from the viewpoint of handling, it is preferably a thickness of 10 mm or less, more preferably 3 mm or less, and most preferably 1.3 mm or less. The lower limit of the thickness is not particularly limited, but it is preferably at least 0.07 mm, more preferably at least 0.15 mm, and most preferably at least 0.3 mm. If it is too thin, it will be easily damaged and handling will become difficult. Moreover, when it is too thick, it will become heavy and handling will become difficult.

Surface treatment can also be performed for the purpose of improving the wettability and adhesiveness of the inorganic substrate. As the surface treatment agent used, coupling agents such as silane coupling agents, aluminum-based coupling agents, and titanate-based coupling agents can be used. In particular, excellent characteristics can be obtained when a silane coupling agent is used.

＜Silane coupling agent (SCA)＞ In the laminate, it is preferable to have a layer of a silane coupling agent (also called a silane coupling agent condensation layer) between the heat-resistant polymer film and the inorganic substrate. In the present invention, the term "silane coupling agent" refers to a compound containing Si (silicon) at 10% by mass or more. By using the silane coupling agent layer, it is possible to thin the intermediate layer between the thermally cured polyamic acid layer and the inorganic substrate, so there is less degassing component during heating, and it is not easy to dissolve even in a wet process. It will produce the effect of staying in a small amount. The silane coupling agent is preferably one that contains a lot of silicon oxide components in order to improve heat resistance, and is particularly preferably one that has heat resistance at a temperature of about 400°C. The thickness of the silane coupling agent layer is preferably 200 nm or less (0.2 μm or less). The range used as a flexible electronic device is preferably below 100 nm (below 0.1 μm), more preferably below 50 nm, and especially preferably below 10 nm. Usually, it is about 0.10 μm or less at the time of production. In addition, in the process where the silane coupling agent is expected to be as little as possible, it can also be used below 5nm. If the thickness is less than 0.1 nm, the peeling strength may decrease or some unattached parts may appear, so it is preferably 0.1 nm or more, more preferably 0.5 nm or more.

The silane coupling agent in the present invention is not particularly limited, but preferably has an amine group or an epoxy group. When heat resistance is required in the manufacturing process, it is preferable to connect Si and amine groups with aromatics.

As specific examples, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, Oxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl )-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, aminophenyltrimethoxysilane, aminophenylethyltrimethoxysilane, aminophenylaminomethyl Phenylethyltrimethoxysilane, etc.

In addition, it is suitable to add other alkoxysilanes, such as tetramethoxysilane, tetraethoxysilane, etc., to the silane coupling agent, or it also includes the case of not adding, adding mixing and heating operations to make the reaction It can also be used after some operations.

In addition, a silane coupling agent previously hydrolyzed can also be used. Specifically, KBP-90 or KBP-64 manufactured by Shin-Etsu Silicone Co., Ltd. can be used.

＜Protective film＞

The laminate of the present invention includes a protective film bonded to the above-mentioned heat-resistant polymer film. The protective film bonded to the heat-resistant polymer film is usually a film for temporarily protecting the surface of the heat-resistant polymer film, and is not particularly limited as long as it can protect the surface of the heat-resistant polymer film and can be peeled off. For example, in addition to PET film, PEN film, polyethylene film, polypropylene film, nylon film, etc., PPS film, PEEK film, aramid film, polyimide film, polyimide ind Indole film and other heat-resistant super engineering plastic film. Among them, PET film is preferable.

In the laminate of the present invention, the arithmetic mean waviness Wa of the surface of the protective film in contact with the heat-resistant polymer film is preferably 30 nm or less. The arithmetic mean waviness Wa is a parameter indicating the magnitude (amplitude) of the waviness in the height direction. Since the fluctuations related to the adhesion of the heat-resistant polymer film are composed of fluctuations with a period of tens of μm, the range of the measurement area of the interference microscope is 60 μm or more in both the x direction and the y direction. When the protective film has an adhesive layer, the adhesive layer is soft and follows the unevenness of the surface of the heat-resistant polymer film, so Wa is not limited.

In the present invention, since the heat-resistant polymer film is supposed to form the device on the surface, it has a very smooth surface. When the arithmetic mean waviness Wa of the surface of the protective film in contact with the heat-resistant polymer film is 30 nm or less, sufficient adhesion to the heat-resistant polymer film can be ensured. Therefore, in the present invention, the arithmetic mean waviness Wa of the protective film is preferably not more than 29 nm, more preferably not more than 28 nm, and most preferably not more than 27 nm. The lower limit of the arithmetic mean waviness Wa of the protective film is not particularly limited, but is usually 5 nm or more.

The arithmetic mean waviness Wa of the protective film can be controlled by the manufacturing conditions (temperature, line speed, surface waviness of the nip roll, nip pressure, etc.) when the protective film is formed. For example, if the molding temperature is lowered, the arithmetic mean waviness Wa tends to be smaller, and by increasing the line speed or lowering the clamping pressure, the arithmetic mean waviness Wa also tends to be smaller. In addition, it can also be controlled by the storage conditions (temperature, humidity, storage time) of the formed protective film. When using a commercially available protective film, an appropriate one can also be selected by measuring the arithmetic mean waviness Wa of the protective film to be used before bonding to the transparent resin film.

The protective film preferably has an adhesive layer on the surface in contact with the heat-resistant polymer film. Adsorption can be exhibited by having an adhesive layer on the protective film. The adhesive layer is not particularly limited, and for example, a urethane-based, silicone-based, or acrylic-based adhesive layer can be used. The adhesive layer system can be produced by applying an adhesive dissolved in a solvent and drying it.

In the present invention, the surface roughness Ra of the surface of the protective film opposite to the heat-resistant polymer film is preferably in the range of 0.02 μm to 1.2 μm, more preferably 0.025 μm to 0.6 μm, and most preferably 0.03 μm to 0.3 μm . As shown in Figure 2 or Figure 3, when stacking long heat-resistant polymer film with protective film/inorganic substrate laminates, the air is exhausted from between the laminates and becomes a vacuum state, making it difficult to take out the laminates one by one. By setting Ra within the above range, an air layer is formed on the surface of the protective film in contact with the heat-resistant polymer film, and the laminate can be taken out one by one from the stacked state.

As a method of controlling the surface roughness of the protective film substrate within a specific range, a method of controlling the surface roughness by adding inorganic particles to a raw resin when producing a film of the protective film substrate can be exemplified. As the inorganic particles, well-known inorganic particles such as silica, alumina, calcium oxide, magnesium oxide, calcium carbonate, magnesium carbonate, calcium phosphate, magnesium phosphate, barium sulfate, talc, and kaolin may be added in a specific amount. The amount of addition varies depending on the elongation ratio when making the base film, the final thickness of the base film, the particle size distribution of the added inorganic particles, etc., but generally speaking, it is 500ppm by mass ratio relative to the mass of the resin of the base film Above, preferably 1000ppm or more, more preferably 2000ppm or more, the upper limit is 10% by mass or less, preferably 3% by mass or less, more preferably 10000ppm or less. As a method of controlling the surface roughness of the protective film base to a specific range, a method of grinding or grinding the surface of the film base to obtain a specific surface roughness can be exemplified. Furthermore, as a method of controlling the surface roughness of the protective film substrate within a specific range, the protective film substrate can be obtained by casting the film raw material on a supporting substrate prepared in advance so as to have a specified surface roughness. method. In addition, a method of controlling the surface roughness of the protective film substrate by pressing an embossing roll or the like processed into a specific surface shape can also be exemplified.

From the viewpoint of cost reduction, a self-adhesive resin film such as polyolefin resin can also be used. Specifically, a polyolefin-based resin film is preferable. In terms of easy availability and low cost, a polypropylene-based resin film or a polyethylene-based resin film is more preferable, and a polyethylene-based resin film is particularly preferable. In addition, examples of polyethylene-based resins include high-pressure low-density polyethylene (LDPE), linear short-chain branched polyethylene (LLDPE), medium-low pressure high-density polyethylene (HDPE), and ultra-low-density polyethylene. (VLDPE), etc. As the resin on the surface adjacent to the heat-resistant polymer film, LLDPE is preferred from the viewpoint of adhesion to the heat-resistant polymer film and processability.

The tensile elastic modulus E of the substrate of the protective film in the present invention is preferably at least 2 GPa, more preferably at least 2.5 GPa. If E is less than 2 GPa, the protective film is stretched due to tension when peeling off the elongated protective film, longitudinal wrinkles are generated, and there is a possibility that the inorganic substrate and the heat-resistant polymer film are peeled off. Moreover, if E is less than 2 GPa, the tension will not propagate smoothly to the peeling end, and there is a possibility that the peeling of the protective film will not proceed uniformly.

The protective film of the present invention is preferably in the shape of a strip. The length of the long side is preferably at least 50 times the length of the short side of the protective film, more preferably at least 100 times, and most preferably at least 200 times. Also, it is preferably at most 100,000 times, more preferably at most 10,000 times, and most preferably at most 5,000 times. The length of the short side is preferably about the same as the length of one side of the aforementioned heat-resistant polymer film and inorganic substrate.

The peel strength (hereinafter also referred to as 90° peel strength) of the 90° peel test between the heat-resistant polymer film and the protective film is preferably (1/3)×F1 or more. Since the peeling strength of the 90° peel test between the heat-resistant polymer film and the protective film is (1/3)×F1 or more, it is possible to suppress peeling of the protective film during handling. The 90° peel strength of the heat-resistant polymer film and the protective film is preferably not less than 0.002N/cm and not more than 0.2N/cm, more preferably not less than 0.003N/cm and not more than 0.15N/cm. When the said 90 degree peel strength is 0.2 N/cm or less, when using a heat-resistant polymer film, a protective film can be peeled suitably. In addition, when the 90° peel strength is 0.002 N/cm or more, unintentional peeling of the protective film from the heat-resistant polymer film can be suppressed in the stage before the use of the heat-resistant polymer film (for example, during transportation).

When peeling the protective film from the heat-resistant polymer film, it is preferable to set the adhesive force between the layers so that the heat-resistant polymer film does not peel off from the inorganic substrate. Since it depends on the peeling speed depending on the type of the adhesive, the adhesive force between the aforementioned layers differs depending on the peeling speed. In particular, when the peeling speed is increased, the peeling strength tends to increase. However, from the viewpoint of shortening the process time, the peeling speed during the aforementioned peeling should be fast, but it is preferable to adjust it so as to obtain a balance of the adhesive force of each layer.

The protective film may contain various additives in the base material layer or the adhesive layer as necessary. Examples of the additives include fillers, antioxidants, light stabilizers, antigelling agents, organic wetting agents, antistatic agents, surfactants, pigments, and dyes. However, in the measurement of ultraviolet transmittance, the protective film is preferably within the range satisfying the following numerical range. When the protective film is composed of a base material and an adhesive layer, the base material preferably does not contain ultraviolet absorbers. Examples of the ultraviolet absorber include those described below.

The aforementioned protective film is measured in ultraviolet transmittance (UV transmittance measurement), and the 50% cut-off wavelength of ultraviolet transmittance is preferably above 240nm, more preferably above 270nm, especially preferably above 300nm, especially preferably above 340nm above. If the 50% cut-off wavelength of the UV transmittance of the protective film is above 240nm, the protective film and the heat-resistant polymer film can be cut off more suitably by the UV laser. Therefore, from the state of inorganic substrate/heat-resistant polymer film/protective film laminate, the heat-resistant polymer film can be cut into any size by laser, or the heat-resistant polymer film with protective film can be cut. into any size.

Examples of the organic ultraviolet absorber include benzotriazole-based, benzophenone-based, cyclic imide-based, and combinations thereof. Among them, benzotriazole-based and cyclic imide-based are particularly preferable from the viewpoint of durability.

Examples of the aforementioned benzotriazole-based ultraviolet absorbers include 2-[2'-hydroxy-5'-(methacryloxymethyl)phenyl]-2H-benzotriazole, 2-[2 '-Hydroxy-5'-(methacryloxyethyl)phenyl]-2H-benzotriazole, 2-[2'-hydroxy-5'-(methacryloxypropyl)benzene Base]-2H-benzotriazole, 2-[2'-hydroxy-5'-(methacryloxyhexyl)phenyl]-2H-benzotriazole, 2-[2'-hydroxy-3 '-tert-butyl-5'-(methacryloxyethyl)phenyl]-2H-benzotriazole, 2-[2'-hydroxy-5'-tert-butyl-3'- (Methacryloxyethyl)phenyl]-2H-benzotriazole, 2-[2'-hydroxyl-5'-(methacryloxyethyl)phenyl]-5-chloro- 2H-Benzotriazole, 2-[2'-Hydroxy-5'-(methacryloxyethyl)phenyl]-5-methoxy-2H-benzotriazole, 2-[2' -Hydroxy-5'-(methacryloxyethyl)phenyl]-5-cyano-2H-benzotriazole, 2-[2'-hydroxy-5'-(methacryloxy Ethyl)phenyl]-5-tert-butyl-2H-benzotriazole, 2-[2'-hydroxy-5'-(methacryloxyethylphenyl]-5-nitro- 2H-benzotriazole etc.

Examples of the aforementioned benzophenone-based ultraviolet absorbers include 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxydiphenyl Methanone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-acetyloxyethoxybenzophenone, 2-Hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxydiphenone Benzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5,5'-disulfobenzophenone・disodium salt etc.

Examples of the cyclic imide ester-based ultraviolet absorber include 2,2'-(1,4-phenylene)bis(4H-3,1-benzo -4-keto), 2-methyl-3,1-benzo -4-keto, 2-butyl-3,1-benzo -4-one, 2-phenyl-3,1-benzo -4-one, 2-(1- or 2-naphthyl)-3,1-benzo -4-one, 2-(4-biphenyl)-3,1-benzo -4-keto, 2-p-nitrophenyl-3,1-benzo -4-keto, 2-m-nitrophenyl-3,1-benzo -4-keto, 2-p-benzoylphenyl-3,1-benzo -4-keto, 2-p-methoxyphenyl-3,1-benzo -4-keto, 2-o-methoxyphenyl-3,1-benzo -4-one, 2-cyclohexyl-3,1-benzo -4-keto, 2-p-(or m-)phthalimidophenyl-3,1-benzo -4-one, 2,2'-(1,4-phenylene)bis(4H-3,1-benzo -4-keto) 2,2'-bis(3,1-benzo -4-keto), 2,2'-ethylenylbis(3,1-benzo -4-keto), 2,2'-tetramethylenebis(3,1-benzo -4-keto), 2,2'-decamethylenebis(3,1-benzo -4-keto), 2,2'-p-phenylene bis(3,1-benzo -4-keto), 2,2'-m-phenylene bis(3,1-benzo -4-one), 2,2'-(4,4'-diphenylene)bis(3,1-benzo -4-keto), 2,2'-(2,6- or 1,5-naphthalene)bis(3,1-benzo -4-one), 2,2'-(2-methyl-p-phenylene)bis(3,1-benzo -4-keto), 2,2'-(2-nitro-p-phenylene)bis(3,1-benzo -4-one), 2,2'-(2-chloro-p-phenylene)bis(3,1-benzo -4-keto), 2,2'-(1,4-cyclohexylene)bis(3,1-benzo -4-keto), 1,3,5-tris(3,1-benzo -4-keto-2-yl)benzene and the like.

Also, 1,3,5-tris(3,1-benzo -4-keto-2-yl)naphthalene and 2,4,6-tri(3,1-benzo -4-keto-2-yl)naphthalene, 2,8-dimethyl-4H,6H-benzo(1,2-d;5,4-d')bis-(1,3)- -4,6-diketone, 2,7-dimethyl-4H,9H-benzo(1,2-d;5,4-d')bis-(1,3)- -4,9-dione, 2,8-diphenyl-4H,8H-benzo(1,2-d;5,4-d')bis-(1,3)- -4,6-diketone, 2,7-diphenyl-4H,9H-benzo(1,2-d;5,4-d')bis-(1,3)- -4,6-dione, 6,6'-bis(2-methyl-4H,3,1-benzo -4-keto), 6,6'-bis(2-ethyl-4H,3,1-benzo -4-keto), 6,6'-bis(2-phenyl-4H,3,1-benzo -4-keto), 6,6'-methylenebis(2-methyl-4H,3,1-benzo -4-keto), 6,6'-methylenebis(2-phenyl-4H,3,1-benzo -4-keto), 6,6'-ethylenylbis(2-methyl-4H,3,1-benzo -4-keto), 6,6'-ethylenylbis(2-phenyl-4H,3,1-benzo -4-keto), 6,6'-butylbis(2-methyl-4H,3,1-benzo -4-keto), 6,6'-butylbis(2-phenyl-4H,3,1-benzo -4-keto), 6,6'-oxybis(2-methyl-4H,3,1-benzo -4-keto), 6,6'-oxybis(2-phenyl-4H,3,1-benzo -4-keto), 6,6'-sulfonylbis(2-methyl-4H,3,1-benzo -4-keto), 6,6'-sulfonylbis(2-phenyl-4H,3,1-benzo -4-one), 6,6'-carbonylbis(2-methyl-4H,3,1-benzo -4-one), 6,6'-carbonylbis(2-phenyl-4H,3,1-benzo -4-keto), 7,7'-methylenebis(2-methyl-4H,3,1-benzo -4-keto), 7,7'-methylenebis(2-phenyl-4H,3,1-benzo -4-keto), 7,7'-bis(2-methyl-4H,3,1-benzo -4-keto), 7,7'-ethylenylbis(2-methyl-4H,3,1-benzo -4-keto), 7,7'-oxybis(2-methyl-4H,3,1-benzo -4-keto), 7,7'-sulfonylbis(2-methyl-4H,3,1-benzo -4-one), 7,7'-carbonylbis(2-methyl-4H,3,1-benzo -4-keto), 6,7'-bis(2-methyl-4H,3,1-benzo -4-keto), 6,7'-bis(2-phenyl-4H,3,1-benzo -4-keto), 6,7'-methylenebis(2-methyl-4H,3,1-benzo -4-keto), 6,7'-methylenebis(2-phenyl-4H,3,1-benzo -4-ketone) and the like can also be used as a cyclic imide ester-based ultraviolet absorber.

In the laminate of the present invention, the peel strength F1 of the 90° peel test between the inorganic substrate and the heat-resistant polymer film, the angle θ formed by the protective film and the heat-resistant polymer film when the protective film is peeled off from the heat-resistant polymer film, and the protective The tension T of the film and the elastic modulus E of the protective film must satisfy the following formulas (1) and (2). Tsinθ＜F1 (1) E＞2GPa (2) Since the above formulas (1) and (2) are satisfied, the protective film can be easily peeled off from the laminate without peeling the heat-resistant polymer film and the inorganic substrate.

The peel strength F1 of the 90° peel test between the inorganic substrate and the heat-resistant polymer film is preferably above 0.02 N/cm, more preferably above 0.05 N/cm, and most preferably above 0.1 N/cm. Moreover, it is preferably 0.3 N/cm or less, more preferably 0.25 N/cm or less, and most preferably 0.2 N/cm or less.

The angle θ formed by the protective film and the heat-resistant polymer film when the protective film is peeled off from the heat-resistant polymer film is preferably at most 30°, more preferably at most 28°, and most preferably at most 25°. When peeling the protective film from the heat-resistant polymer film, when the radius of curvature of the protective film is sufficiently thinner than the thickness of the protective film substrate, the smaller θ is, the smaller the force required for peeling is. θ can be controlled within a preferable range by providing a peeling auxiliary roller 51 as shown in FIG. 5 ( FIG. 6 ). It is preferable to adjust the position of the peeling auxiliary roller so that it can be controlled to a value suitable for θ. The peeling angle θ can be obtained from the angle between the tangent to the peeling auxiliary roller 51 at the peeling start position (peeling start point) of the protective film and the heat-resistant polymer film. Specifically, the measurement of the peeling angle θ can be performed using a digital angle meter, for example, WR300 manufactured by Wixey, Bevel Box manufactured by Shino Seiki Co., Ltd., etc. can be used.

Also, when peeling the protective film from the heat-resistant polymer film in the present invention, the tension T applied to the protective film is preferably in the range of 0.1N/cm to 2.5N/cm, more preferably in the range of 0.5N/cm to 2N/cm . In addition, the elastic modulus E of the protective film exceeds 2 GPa, preferably 2.1 GPa or more, more preferably 2.2 GPa or more, and is preferably 10 GPa or less, more preferably 8 GPa or less, especially preferably 6 GPa or less. Tsinθ is smaller than the peel strength F1, preferably not more than 0.95×F1, more preferably not more than 0.9×F1, and most preferably not more than 0.85×F1. In addition, the tension T is preferably adjusted so that the elastic modulus E of the protective film base material and the peeling angle θ are in the range of 0.2≦ETsinθ≦4. When ETsinθ is in this range, the protective film can be peeled off suitably from the heat-resistant polymer film. A more preferable range of ETsinθ is not less than 0.21 and not more than 3.9, and an even more preferable range is not less than 0.22 and not more than 3.8. By achieving a balance between the tension T, the propagation of the apparent tension T to the peeling point E, and the peeling angle θ, especially when the peeling strength of the protective film and the heat-resistant polymer film exceeds (1/3)×F1, high heat resistance can be achieved. The molecular film desirably peels off the protective film.

＜Manufacturing method of laminate＞ The laminate system of the inorganic substrate and the heat-resistant polymer film can be manufactured by casting the aforementioned polymer solution or polymer precursor solution on the inorganic substrate and heating it.

Well-known methods can be used as a casting method of a polymer solution or a polymer precursor solution. Examples thereof include known casting methods such as gravure coating, spin coating, screen coating, dip coating, bar coating, knife coating, roll coating, and die coating.

When the polymer precursor solution is a polyamic acid solution, the aforementioned polymerization solution can be used as it is as the polyamic acid solution, but the solvent can be removed or added as necessary. As a solvent that can be used for the polyamic acid solution, in addition to N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, for example, Examples thereof include dimethylsulfoxide, hexamethylphosphoramide, acetonitrile, acetone, and tetrahydrofuran. Also, as an auxiliary solvent, xylene, toluene, benzene, diethylene glycol ethyl ether, diethylene glycol dimethyl ether, 1,2-bis-(2-methoxyethoxy)ethane, Alkane bis (2-methoxyethyl) ether, butyl cellothreon, butyl cellothreoacetate, propylene glycol methyl ether and propylene glycol methyl ether acetate.

The polyamic acid of the present invention is preferably thermally imidized (thermally cured) at a temperature of 300°C to 450°C. That is, the polyimide of the present invention is preferably one in which the aforementioned polyamic acid is thermally imidized (thermocured) at 300 to 450°C.

Thermal imidization is a method in which the imidization reaction is carried out only by heating without the action of a dehydrating ring-closing agent. The heating temperature and heating time at this time can be suitably determined, for example, what is necessary is just to be as follows. First, in order to volatilize the solvent, it is heated at a temperature of 90 to 200° C. for 3 to 120 minutes. The heating environment can be carried out under air, under reduced pressure or in an inert gas such as nitrogen. Moreover, well-known devices, such as a hot-air oven, an infrared oven, a vacuum oven, and a hot plate, can be used as a heating means. Next, in order to further imidize, it is heated at a temperature in the range of 200 to 450°C for 3 to 240 minutes. The heating conditions at this time are preferably gradually changed from a low temperature to a high temperature. Also, the maximum temperature is preferably in the range of 300 to 450°C. If the maximum temperature is lower than 300° C., thermal imidization will be difficult to proceed, and the mechanical properties of the obtained polyimide film will be deteriorated, which is not suitable. If the maximum temperature is higher than 450° C., the thermal degradation of the polyimide will progress and the characteristics will deteriorate, which is not preferable. Also, depending on the type and thickness of the polyamic acid, the type or surface state of the inorganic substrate, the heating conditions during heating, and the heating method, the thin film may be naturally peeled off from the inorganic substrate during the heat treatment. If spontaneous peeling occurs, it will be difficult to obtain a laminate having excellent properties, which is not preferable. In general, the thicker the film, the easier it is for natural peeling to occur, so it is preferable to adjust the aforementioned conditions together with the thickness. In addition, in order to suppress natural peeling, the operations of casting the polyamic acid solution and thermal imidization may be performed in plural times.

The content of the solvent contained in the polyimide is preferably at most 1% by mass, more preferably at most 0.5% by mass, and most preferably at most 0.1% by mass. The lower the content of the solvent, the better, so the lower limit is not particularly limited, but industrially, it is sufficient to be at least 0.01% by mass, and 0.05% by mass is also acceptable.

The polyamic acid solution in the present invention is applied to the inorganic substrate, and different polyamic acid solutions can be applied in multiple layers sequentially or simultaneously. The so-called different polyamic acid solutions here specifically refer to polyamic acid solutions with different compositions, polyamic acid solutions with different imidization rates, types of inorganic particles or additives added, Different amounts of polyamide acid solutions. In addition to the polyamic acid solution that directly contacts the inorganic substrate, it can also be a polyimide solution that has undergone thermal imidization.

Coating of a plurality of polyamic acid solutions on an inorganic substrate can be performed using, for example, a two-layer die coater or the like. Using a multi-layer die coater, or by sequential coating, a laminate of heat-resistant polymer films (polyimide films) having an inorganic substrate and a multi-layer structure of two or more layers can be obtained.

The application of the polyamic acid solution in the present invention to the inorganic substrate can also be done after the first layer is applied to the inorganic substrate, and then heated at a temperature of 100-200°C for 3-120 minutes to evaporate the solvent, and then the second layer can be applied from above. layer of polyamic acid solution.

In the present invention, the laminate of the inorganic substrate and the polyimide film can be coated with a polyamide acid solution on the inorganic substrate, and then heated after the polyimide film is bonded before heating to finally become an inorganic substrate and a polyimide film. Laminated body of imide.

In order to obtain the laminate of the inorganic substrate and the polyimide film in the present invention, it is also possible to heat the polyamic acid solution pre-coated with a single layer or multiple layers on another support to form a self-supporting film After being attached, it is bonded to an inorganic substrate and heated to obtain it.

The laminate of the inorganic substrate and the polyimide thin film in the present invention can also be obtained by laminating a thermosetting polyamic acid which has been previously formed into a single layer or a multilayer film to the inorganic substrate. Single-layer or multi-layer polyimide film can be obtained by coating polyamide acid solution on the support of metal belt or resin film, drying it to become a self-supporting film, and then performing thermal imidization . The coating of the polyamic acid solution on the support may be performed in multiple layers at the same time, or the first layer may be coated and dried, and the polyamic acid solution may be coated thereon, dried, and imidized. When laminating three or more layers of the polyamic acid solution, similarly, the coating and heating can be repeated simultaneously or sequentially to obtain a multilayer film.

The laminate of the inorganic substrate and the heat-resistant polymer thin film of the present invention can also be produced by the following procedure, for example. At least one surface of the inorganic substrate is treated with a silane coupling agent in advance, and the surface treated with the silane coupling agent is laminated with the film-like polyimide, and the two are laminated under pressure to obtain a laminate. In addition, at least one surface of the polyimide in the form of a film is treated with a silane coupling agent in advance, and the surface treated with the silane coupling agent is laminated with the inorganic substrate, and the two are laminated by pressurization to obtain a laminate. . As the pressurization method, general pressurization or lamination in the atmosphere or pressurization or lamination in a vacuum can be mentioned. In order to obtain a comprehensive and stable peel strength, it is preferable to use the atmosphere in a large-sized laminate (for example, exceeding 200mm). of lamination. On the other hand, in the case of a laminate having a small size of about 200 mm or less, pressurization in a vacuum is preferable. The degree of vacuum is sufficient for the vacuum produced by a common oil rotary pump, and it is sufficient as long as it is about 10 Torr or less. The preferred pressure is 1MPa to 20MPa, more preferably 3MPa to 10MPa. If the pressure is high, the substrate may be damaged, and if the pressure is low, there may be unadhered parts. The preferred temperature is 90°C to 300°C, more preferably 100°C to 250°C. If the temperature is high, the polyimide will be damaged, and if the temperature is low, the adhesion will be weakened.

The shape of the laminate is not particularly limited, and may be a square or a rectangle. It is preferably rectangular, and the length of the long side is preferably at least 300 mm, more preferably at least 500 mm, and most preferably at least 1000 mm. The upper limit is not particularly limited, but industrially it is sufficient if it is 20000 mm or less, and 10000 mm or less is also fine. In addition, the radius of the circumscribed circle of the inorganic substrate is preferably 330 mm or more. The laminated body of the present invention is more preferably 350 mm or more, particularly preferably 400 mm or more, from the standpoint that even large ones can be packed and stored or transported in a stacked form. In addition, industrially, it is enough to be 30000 mm or less, and 20000 mm or less is also fine.

＜Adhesive＞ Between the inorganic substrate and the heat-resistant polymer film of the present invention, it is preferable that there is substantially no adhesive layer. Here, the adhesive layer referred to in the present invention means that the Si (silicon) component is less than 10% by mass ratio (less than 10% by mass). In addition, the one that is substantially not used (does not exist in between) means that the thickness of the adhesive layer interposed between the inorganic substrate and the heat-resistant polymer film is preferably 0.4 μm or less, more preferably 0.3 μm or less, It is especially preferably 0.2 μm or less, particularly preferably 0.1 μm or less, most preferably 0 μm.

In the present invention, after fabricating the laminate of the inorganic substrate and the heat-resistant polymer film, a long protective film is attached to the surface of the heat-resistant polymer film.

In the present invention, after manufacturing the laminate of the inorganic substrate and the heat-resistant polymer film, a second protective film may be attached to the surface of the inorganic substrate opposite to the heat-resistant polymer film for the purpose of protecting the inorganic substrate and the like. The second protective film can separate each laminated body of the inorganic substrate/heat-resistant polymer film to be independent, or the laminated body can be formed into a continuous sheet and continuous through the second protective film.

The bonding timing of the first protective film and the second protective film to the inorganic substrate/heat-resistant polymer film is as shown in Fig. 1(b), and may be simultaneously or sequentially. The bonding order is not particularly limited, but from the viewpoint of protecting the surface of the heat-resistant polymer film, it is preferable to bond the first protective film first.

As a heat-resistant polymer film, when a pre-cured polyamide thermosetting product (specifically polyimide film, etc.) is used in a laminate, the first protective film and/or the second protective film can be pre-cured Bonded to heat-cured polyamide. At that time, it was possible to use pre-cut single-piece films to make laminates, or to roll out long roll-shaped films and paste them on inorganic substrates, and cut the films before and after lamination to form a single-piece laminate. body. Even if it is a layered body that is once a single sheet, it can be formed into a continuous sheet by bonding the first and/or second protective film.

In the present invention, a plurality of sheets of the above-mentioned laminate, preferably 4 or more sheets, more preferably 10 or more sheets, can be stacked. When stacking, the directions of the laminated bodies may be the same or different, but the same directions are preferred. When forming a stack in the present invention, since the coefficient of dynamic friction between the contacting surfaces is within a specific range, it is easy to take out the laminated body individually from the stack. In addition, only the same kind of laminates may be used as the stacked laminates, and different kinds of laminates may be used freely without any problem.

In the present invention, the laminated body can be stored in the stacked state thus obtained. At the time of storage, it is preferable to pack the above-mentioned laminates in a stacked state. The stacking system of the present invention can cope with any of the following situations during storage: the case where the stacked inorganic substrates are stored in a horizontal direction, and the case where they are stored in a vertical direction, which is close to vertical and inclined at 75 to 89 degrees Left and right for storage. [Example]

The following examples are given to illustrate the present invention more specifically, but the present invention is not limited to the following examples. The physical property evaluation methods in the following examples are as follows.

As protective films PF4 and PF5, commercially available products were used. PF4: Toretec (registered trademark) 7832C (protective film manufactured by Toray Co., Ltd.) PF5: Toretec (registered trademark) 7332 (protective film manufactured by Toray Co., Ltd.)

<Preparation of polyamic acid solution A1> After replacing the reaction container with nitrogen gas introduction tube, degree meter, and stirring bar with nitrogen, add 223 parts by mass of 5-amino-2-(p-aminophenyl)benzene and azole (DAMBO), 4416 parts by mass of N,N-dimethylacetamide and make it completely dissolved, then, together with 217 parts by mass of pyromellitic dianhydride (PMDA), the colloidal Dispersion of silica dispersed in dimethylacetamide ("Snowtex (registered trademark) DMAC-ST30" manufactured by Nissan Chemical Industry Co., Ltd.), a polymer made of silica (slip agent) in polyamic acid solution It added so that it might become 0.12 mass % in solid content total amount, it stirred at the reaction temperature of 25 degreeC for 24 hours, and obtained brown and viscous polyamic acid solution A.

＜Preparation of polyamide acid solution A2＞ After replacing the reaction vessel with nitrogen gas introduction tube, reflux tube and stirring bar with nitrogen, 22.73 parts by mass of 4,4'-diaminobenzamide aniline (DABAN), 201.1 parts by mass of N,N-di Dimethylacetamide (DMAc) and a dispersion obtained by dispersing colloidal silica (slip agent) in dimethylacetamide (Nissan Chemical Industry "Snowtex (registered trademark) DMAC-ST-ZL"), Colloidal silica (slip agent) was added so as to be 0.4% by mass of the total polymer solid content in the polyamic acid solution and completely dissolved. Next, after adding 22.73 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) as a solid, it was stirred at room temperature for 24 hours. Then, 173.1 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution A2 having a solid content (NV) of 12 mass % and a reduced viscosity (ηsp/C) of 3.10 dl/g.

＜Preparation of polyamide acid solution A3＞ After replacing the reaction vessel with nitrogen gas inlet tube, reflux tube, and stirring bar with nitrogen, 22.0 parts by mass of 2,2'-bistrifluoromethyl-4,4'-diaminobiphenyl (TFMB), 252.1 parts by mass of DMAc and a dispersion ("Snowtex (registered trademark) DMAC-ST-ZL" manufactured by Nissan Chemical Industry Co., Ltd.) formed by dispersing colloidal silica as a slip agent in dimethylacetamide, using silica (Slip agent) was added so that the total polymer solid content in the polyamic acid solution became 0.4% by mass and completely dissolved, and then 22.0 parts by mass of 3,3',4,4'-linked Phenyltetracarboxylic dianhydride (BPDA) was added as it was divided into solids, and stirred at room temperature for 24 hours. Then, 165.7 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution A3 having a solid content (NV) of 11 mass % and a reduced viscosity of 3.5 dl/g.

＜Preparation of polyimide solution B1＞ KPI-MX300F (manufactured by Kawamura Sangyo) was dissolved in DMAc to have a solid content (NV) of 12%, and stirred to obtain a polyimide solution B1.

＜Preparation of polyamic acid solution A4＞ After replacing the reaction vessel with nitrogen gas introduction tube, reflux tube, and stirring bar with nitrogen, 33.36 parts by mass of 2,2'-bistrifluoromethyl-4,4'-diaminobiphenyl (TFMB), 270.37 parts by mass of N-methyl-2-pyrrolidone (NMP) and a dispersion obtained by dispersing colloidal silica in dimethylacetamide (Nissan Chemical Industry "Snowtex (registered trademark) DMAC-ST -ZL") was added so that the silica was 0.3% by mass in the total polymer solid content in the polyamic acid solution to dissolve it completely, and then 9.81 parts by mass of 1, 2, 3, 4 -Cyclobutanetetracarboxylic dianhydride (CBDA), 11.34 parts by mass of 3,3',4,4'-biphenyltetracarboxylic acid (BPDA), 4.85 parts by mass of 4,4'-oxydiphthalic diphthalic acid After adding formic acid dianhydride (ODPA) by dividing it as it was as a solid, it stirred at room temperature for 24 hours. Then, 165.7 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution A4 having a solid content of 18 mass % and a reduced viscosity of 2.7 dl/g.

＜Preparation of polyamide acid solution A5＞ After replacing the reaction vessel with nitrogen gas introduction tube, reflux tube, and stirring rod with nitrogen, 470.8 parts by mass of 2,2'-bistrifluoromethyl-4,4'-diaminobiphenyl (TFMB), A dispersion obtained by dispersing 6766 parts by mass of N-methyl-2-pyrrolidone (NMP) and colloidal silica as a slip agent in dimethylacetamide (Nissan Chemical Industry "Snowtex (registered trademark) )DMAC-ST-ZL"), add silica (slip agent) to 0.3% by mass of the total polymer solid content in the polyamic acid solution to completely dissolve it, and then add 192.4 parts by mass After adding pyromellitic dianhydride (PMDA) and 173.0 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) directly as solids, stir at room temperature for 24 hours . Then, a polyamic acid solution A5 having a solid content of 11% by mass and a reduced viscosity of 3.50 dl/g was obtained.

＜Preparation of polyamic acid solution A6＞ According to the methods described in Synthesis Example 1, Example 1 and Example 2 of International Publication No. 2011/099518, norbornane-2-spiro-α-cyclopentanone-α'-spiro-2”-norbornane was synthesized Alkane-5,5",6,6"-tetracarboxylic dianhydride (CpODA). Next, after replacing the reaction vessel with nitrogen gas introduction tube, reflux tube, and stirring bar with nitrogen, 22.73 parts by mass of 4,4'-diaminobenzamide aniline (DABAN), 371.1 parts by mass of N,N -Dimethylacetamide (DMAc) and a dispersion obtained by dispersing colloidal silica (slip agent) in dimethylacetamide (Nissan Chemical Industry "Snowtex (registered trademark) DMAC-ST-ZL" ), so that colloidal silica (slip agent) becomes 0.4% by mass in the total polymer solid content in the polyamic acid solution, add and dissolve it completely, and then add 38.43 parts by mass of norbornane -2-spiro-α-cyclopentanone-α'-spiro-2"-norbornane-5,5",6,6"-tetracarboxylic dianhydride (CpODA) was added directly as a solid in fractions, Stir at room temperature for 24 hours. Then, add 173.1 parts by mass of DMAc for dilution to obtain a polyamic acid solution A6 with a solid content (NV) of 12 mass % and a reduced viscosity (ηsp/C) of 3.20 dl/g.

＜Preparation of polyamideimide solution B2＞ After substituting nitrogen in the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod, add 450.0 parts by weight of 2,2'-bis(trifluoromethyl)-4,4' to the reaction vessel under a nitrogen atmosphere -diaminobiphenyl (TFMB) and 7680 parts by weight of N,N-dimethylacetamide (DMAc), TFMB was dissolved in DMAc while stirring at room temperature. Next, 180.9 parts by weight of 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA) was added, and stirred at room temperature for 3 hours. Then, 41.9 parts by weight of 4,4'-oxybis(benzoyl chloride) (OBBC) was added, followed by addition of 172.9 parts by weight of terephthalyl chloride (TPC), followed by stirring at room temperature for 1 hour. Next, add 46.3 parts by weight of picoline as an imidization accelerator and 130.4 parts by weight of acetic anhydride as an imidation agent, stir at room temperature for 30 minutes, then raise the temperature to 70°C, and stir for 3.5 Hour, obtain polyamideimide solution b2-1. Next, move 4000 parts by mass of the obtained polyamidoimide solution b2-1 containing the imidization agent and the imidization accelerator to a reaction vessel equipped with a stirring device and stirring blades at a speed of 120 rpm 60,000 parts by mass of methanol was dropped therein at a rate of 400 parts by mass/min while stirring while maintaining a temperature of 15 to 25°C. When about 3200 parts by mass of methanol was injected, the polyimide solution was confirmed to be cloudy, and the precipitation of powdery polyimide was confirmed. Then add the remaining methanol to complete the precipitation of polyimide. Next, filter and separate the contents of the reaction vessel with a suction filter, and wash and filter with 4000 parts by mass of methanol. Then, 2000 parts by mass of the polyimide powder separated by filtration was dried at 50°C for 24 hours, and at 260°C for 2 hours, using a dryer with a local exhaust device to remove the remaining volatile components , to obtain polyamideimide powder b2-2. The reduced viscosity of the obtained polyamideimide powder b2-2 was 4.50dl/g. Next, to 3000 parts by mass of DMAc, a dispersion obtained by dispersing colloidal silica as a slip agent in DMAc ("Snowtex (registered trademark) DMAC-ST-ZL" manufactured by Nissan Chemical Industries) was added to make the silica ( slippery agent) becomes 0.3% by mass in the polymer solid content total amount in the polyimide solution, makes it dissolve completely, then makes the polyamideimide powder b2-2 of 400 mass parts dissolve, obtains polyimide Amidoimide solution B2.

＜Preparation of protective film PF1＞ The following were mixed to obtain an adhesive composition C1. Linear polyorganosiloxane having vinyl groups only at both ends (solvent-free type, Mw: 80,000): 68.30 parts by mass Organohydrogenpolysiloxane (solvent-free type, Mw: 2,000): 0.41 parts by mass Platinum catalyst (Shin-Etsu Chemical Co., Ltd., PL-56): 1.00 parts by mass Ultraviolet absorber (Cyasorb UV-3638 (manufactured by CYTEC)): 0.3 parts by mass Reaction control agent (3-methyl-1-butyn-3-ol): 0.10 parts by mass Toluene: 30.19 parts by mass Toyobo Co., Ltd.'s polyethylene terephthalate (PET) film (A4100, thickness 50 μm) was subjected to corona treatment as a base treatment, and the adhesive composition C1 was applied to the PET film immediately after the corona treatment. Coating was performed in an environment of 25° C. and 85% RH, and was performed so that the thickness after drying became 10 μm. Then, continuously heat in an oven at 150° C. for 100 seconds to crosslink, and stick a release film (polyethylene terephthalate (PET) film coated with silicone resin, thickness 25 μm) on the side of the adhesive layer. ) to obtain a long protective film PF1 having a laminated structure of "PET film/adhesive layer/peeling film".

＜Preparation of protective film PF2＞ For 100 parts by mass of acrylic polymer (copolymer of 2-ethylhexyl acrylate and 4-hydroxybutyl acrylate (copolymerization ratio 100:8), weight average molecular weight: 200,000), add 1.5 parts by mass as Coronate HX (manufactured by Tosoh Co., Ltd., polyisocyanate for coatings) of functional isocyanate and 0.3 parts by mass of KP-341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., polyether-modified organosiloxane) as modified organosiloxane ), stirring and mixing to obtain the adhesive composition C2. The obtained adhesive composition C2 was coated on the polyethylene terephthalate (A-PET, 150 μm) film of NANIWA Paper Industry Co., Ltd. that had been subjected to corona treatment in advance, and dried continuously at 100°C. Remove the solvent, form an adhesive layer with a thickness of 10 μm on the PET film, and roll it while attaching a release film (polyethylene terephthalate (PET) film coated with silicone resin, thickness 25 μm) on the adhesive layer side. Taken to obtain a long protective film PF2 having a laminated structure of "PET film/adhesive layer/peeling film".

＜Preparation of protective film PF3＞ While stirring 100 parts by mass of urethane-based solvent-based adhesive US-902-50 (manufactured by Lion Specialty Chemicals, ethyl acetate solvent, solid content 50% by mass), 5.4 parts by mass of crosslinking Agent N (manufactured by Lion Specialty Chemicals Co., Ltd.) and 2 parts by mass of an ultraviolet absorber (Cyasorb UV-3638 (manufactured by Cytec Corporation)) were reacted at 40° C. for 20 minutes. After filtering the resulting solution with a PTFE cartridge filter (0.45 μm), apply it to polyethylene terephthalate (A- PET, 150μm) film, continuously heated at 100°C for 2 minutes, while attaching a release film (polyethylene terephthalate (PET) film coated with silicone resin, thickness 25μm) on the side of the adhesive layer ) to obtain a long protective film PF3 having a laminated composition of "PET film/adhesive layer/peeling film".

＜Fabrication of laminate L1 of inorganic substrate and heat-resistant polymer film＞ Using a bar coater, cast the polyamic acid solution A1 on a rectangular alkali-free glass (OA11G made by NEG) with a thickness of 500mm x 400mm and a thickness of 0.7mm so that the dry thickness becomes 15μm, and dry it in a hot air oven at 110°C 1 hour. The laminate of the dried product of glass and polyimide solution obtained in this way was gradually heated up to 450 °C at 5 °C/min, and the solvent was evaporated by further heating for 10 minutes to obtain a polyimide film and polyimide film with a thickness of about 15 μm. Laminates of alkali-free glass plates. In the same way, 10 laminates were produced, and PF1 was attached as shown in Fig. 1(a) to obtain a continuous sheet-shaped laminate L1. Bonding is specifically performed by lamination in a clean environment. The lamination system is performed between a metal roll and a rubber roll, and the temperature during lamination is 22° C., 52% RH, and 2 MPa at normal temperature.

＜Fabrication of laminate L2 of inorganic substrate and heat-resistant polymer film＞ A laminate L2 was obtained in the same manner as L1 except that PF2 was used instead of PF1.

＜Fabrication of laminate L3 of inorganic substrate and heat-resistant polymer film＞ Using a bar coater, cast the polyamic acid solution A2 on a rectangular alkali-free glass (OA11G made by NEG) with a thickness of 500mm×400mm and a thickness of 0.7mm so that the dry thickness becomes 15 μm, and dry it in a hot air oven at 110°C 1 hour. The laminate of the dried product of glass and polyimide solution obtained in this way was gradually heated up to 400 °C at 5 °C/min, and the solvent was evaporated by further heating for 10 minutes to obtain a polyimide film and polyimide film with a thickness of about 15 μm. Laminates of alkali-free glass plates. In the same manner, 10 laminates were produced, and PF2 was pasted as shown in Fig. 1(a) to obtain a continuous sheet-shaped laminate L3. Bonding is specifically performed by lamination in a clean environment. The lamination system is performed between a metal roll and a rubber roll, and the temperature during lamination is 22° C., 52% RH, and 2 MPa at normal temperature.

＜Fabrication of laminate L4 of inorganic substrate and heat-resistant polymer film＞ Using a bar coater, cast the polyimide solution B1 on a rectangular alkali-free glass (OA11G made by NEG) with a thickness of 500mm×400mm and a thickness of 0.7mm so that the dry thickness becomes 15 μm, and dry it in a hot air oven at 110°C 1 hour. The laminated body of the dried product of glass and polyimide solution obtained in this way was gradually heated up to 350 °C at 5 °C/min, and the solvent was evaporated by further heating for 10 minutes to obtain a polyimide film and polyimide film with a thickness of about 15 μm. Laminates of alkali-free glass plates. In the same way, 10 laminates were produced, and PF2 was attached as shown in Fig. 1(a) to obtain a continuous sheet-shaped laminate L4. Bonding is specifically performed by lamination in a clean environment. The lamination system is performed between a metal roll and a rubber roll, and the temperature during lamination is 22° C., 52% RH, and 2 MPa at normal temperature.

＜Fabrication of laminate L5 of inorganic substrate and heat-resistant polymer film＞ A laminate L5 was obtained in the same manner as L1 except that PF3 was used instead of PF1.

＜Production of laminate L6 of inorganic substrate and heat-resistant polymer film＞ A laminate L6 was obtained in the same manner as L1 except that PF4 was used instead of PF1.

＜Production of laminate L7 of inorganic substrate and heat-resistant polymer film＞ A laminate L7 was obtained in the same manner as L1 except that PF5 was used instead of PF1.

＜Production of laminate L8 of inorganic substrate and heat-resistant polymer film＞ Using a bar coater, cast the polyamic acid solution A3 on a rectangular alkali-free glass (OA11G made by NEG) with a thickness of 500mm x 400mm and a thickness of 0.7mm so that the dry thickness becomes 15μm, and dry it in a hot air oven at 110°C 1 hour. The laminated body of the dried product of glass and polyimide solution obtained in this way was gradually heated up to 350 °C at 5 °C/min, and the solvent was evaporated by further heating for 10 minutes to obtain a polyimide film and polyimide film with a thickness of about 15 μm. Laminates of alkali-free glass plates. In the same way, 10 laminates were produced, and PF2 was pasted as shown in Fig. 1(a) to obtain a continuous sheet-shaped laminate L8. Bonding is specifically performed by lamination in a clean environment. The lamination system is performed between a metal roll and a rubber roll, and the temperature during lamination is 22° C., 52% RH, and 2 MPa at normal temperature.

＜Production of laminate L9 of inorganic substrate and heat-resistant polymer film＞ Laminate L9 was obtained in the same manner as L8 except that polyamic acid solution A4 was used instead of polyamic acid solution A3.

＜Fabrication of laminate L10 of inorganic substrate and heat-resistant polymer film＞ A laminate L10 was obtained in the same manner as L8 except that the polyamic acid solution A5 was used instead of the polyamic acid solution A3.

＜Fabrication of laminate L11 of inorganic substrate and heat-resistant polymer film＞ A laminate L11 was obtained in the same manner as in L8, except that polyamic acid solution A5 was used instead of polyamic acid solution A3, and PF1 was used instead of PF2.

＜Fabrication of laminate L12 of inorganic substrate and heat-resistant polymer film＞ A laminate L12 was obtained in the same manner as in L8, except that the polyamic acid solution A5 was used instead of the polyamic acid solution A3, and PF3 was used instead of PF2.

＜Production of laminate L13 of inorganic substrate and heat-resistant polymer film＞ A laminate L13 was obtained in the same manner as L8 except that the polyamic acid solution A6 was used instead of the polyamic acid solution A3.

＜Production of laminate L14 of inorganic substrate and heat-resistant polymer film＞ A laminate L14 was obtained in the same manner as L8 except that the polyamide imide solution B2 was used instead of the polyamide acid solution A3.

＜Production of laminate L15 of inorganic substrate and heat-resistant polymer film＞ A laminate L15 was obtained in the same manner as in L8, except that polyamideimide solution B2 was used instead of polyamic acid solution A3, and PF1 was used instead of PF2.

＜Production of laminate L16 of inorganic substrate and heat-resistant polymer film＞ A laminate L16 was obtained in the same manner as in L8, except that polyamideimide solution B2 was used instead of polyamic acid solution A3, and PF3 was used instead of PF2.

＜90°peel test (90°peel strength)＞ The measurement of the 90° peel strength of each layer of the laminate obtained above was carried out under the following conditions. When only the intended layer cannot be peeled off, the lower layer is firmly fixed with an adhesive tape, and the measurement is performed. The results are shown in Tables 1 and 2. Measuring device : JSV-H1000 manufactured by Japan Measurement System Measuring temperature : Room temperature (25°C) Peeling speed : 100mm/min Environment : Atmosphere Determination of sample width : 1cm The measurement was performed 5 times, and the average value was regarded as a measured value.

[Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 laminate L1 L2 L3 L4 L5 L8 L9 L10 L11 L12 protective film PF1 PF2 PF2 PF2 PF3 PF2 PF2 PF2 PF1 PF3 T(N/cm) 0.8 0.65 1.6 1.6 1.2 1.2 1.2 1.4 1.5 1.6 θ(°) 8 10 5 25 5 5 8 5 5 5 F1(N/cm) 0.15 0.15 0.2 0.4 0.15 0.2 0.3 0.2 0.2 0.2 Protective film/heat-resistant polymer film peel strength (N/cm) 0.002 0.06 0.07 0.06 0.08 0.07 0.07 0.07 0.008 0.09 Tsinθ 0.11 0.11 0.14 0.68 0.1 0.1 0.17 0.12 0.13 0.14 Tsinθ<F1 ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ E(GPa) 3.2 2.2 2.2 5.5 2.2 2.2 2.2 2.2 3.2 2.2 ET sin θ 0.35 0.24 0.31 3.74 0.22 0.22 0.37 0.26 0.42 0.31 Protective Film Peeling ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

[Table 2] Example 11 Example 12 Example 13 Example 14 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative Example 5 laminate L13 L14 L15 L16 L6 L6 L7 L3 L2 protective film PF2 PF2 PF1 PF3 PF4 PF4 PF5 PF2 PF2 T(N/cm) 1.6 1.6 1.7 2 1.6 1.6 0.65 0.65 2.6 θ(°) 5 8 8 8 5 5 10 20 10 F1(N/cm) 0.3 0.4 0.4 0.4 0.15 0.15 0.08 0.2 0.15 Protective film/heat-resistant polymer film peel strength (N/cm) 0.07 0.07 0.01 0.11 0.042 0.042 0.06 0.06 0.06 Tsinθ 0.14 0.22 0.24 0.28 0.14 0.14 0.11 0.22 0.45 Tsinθ<F1 ○ ○ ○ ○ ○ ○ x x x E(GPa) 2.2 2.2 3.2 2.2 0.3 0.65 2.2 2.2 2.2 ET sin θ 0.48 0.48 0.77 0.62 0.04 0.09 0.24 0.48 0.99 Protective Film Peeling ○ ○ ○ ○ x x x x x

<Tensile elastic modulus of protective film> A strip of 100 mm x 10 mm was cut out in the flow direction (coating direction, MD direction) and width direction (perpendicular to the coating direction, TD direction) of the protective film respectively as a test piece. Using a tensile testing machine (manufactured by Shimadzu Corporation, Autograph (R) model name AG-5000A), under the conditions of a tensile speed of 50mm/min and a distance between chucks of 40mm, the tensile elasticity was measured for each of the MD direction and the TD direction Modulus. The results are shown in Tables 1-2.

<Measurement of tension T when the protective film is peeled> The peeling of the protective film is carried out, for example, as shown in FIG. 5 . The lamination system of the heat-resistant polymer film and the inorganic substrate formed into a continuous sheet by the elongated protective film 14 is transported by the conveyor belt 52 , and the protective film is taken up while the peeling angle θ is appropriately adjusted by the peeling auxiliary roller 51 . The winding tension at this time was read with a tensiometer, and it was set as tension T. A tensiometer for reading the winding tension is not pre-set, but a hand-held tensiometer can be used for measurement using a dummy film.

<Measurement of peeling angle θ> Stop the device in the state shown in Fig. 5 (Fig. 6), and measure the peeling angle θ using a digital goniometer. As a digital angle meter, a Bevel Box manufactured by Niigata Seiki is used. Specifically, in the comparison measurement mode, the heat-resistant polymer film 15 is used as a reference plane, and the gradient from the peeling start point of the protective film 14 to the peeling auxiliary roller 51 is obtained. Moreover, WR300 etc. made from Wixey can also be used, for example. Also, when a sufficient space for the above-mentioned measurement cannot be secured on the protective film, an angle gauge such as a digital angle meter (measured by SHINWA) can be used.

＜Whether the protective film can be peeled off＞ The laminate of the inorganic substrate/heat-resistant polymer film after peeling off the protective film was visually observed. Compared with before peeling of the protective film, the case where no peeling occurred between the inorganic substrate/heat-resistant polymer film was regarded as 0, and the case where peeling occurred or wrinkles were introduced into the heat-resistant polymer film due to the elongation of the protective film or occurred The case where the position of the heat-resistant polymer film was shifted was regarded as x. In Examples 1 to 14, no peeling occurred between the inorganic substrate/heat-resistant polymer film, and the protective film could be peeled off. On the other hand, in Comparative Examples 1 and 2, when the protective film was peeled off, the protective film was stretched, and the heat-resistant polymer film was peeled off, and wrinkles were generated. The heat-resistant polymer films of Comparative Examples 3 to 5 were peeled from the inorganic substrate together with the protective film. [Possibility of industrial use]

As mentioned above, the inorganic substrate/heat-resistant polymer film/elongated protective film laminate of the present invention can be processed in a state where the surface of the heat-resistant polymer film is protected by the protective film, and when the surface of the heat-resistant polymer film is processed , the protective film can be peeled off without problems. The present invention can be usefully utilized for manufacturing a flexible device or the like by peeling the polymer film from the inorganic substrate after microfabrication of the polymer film using such a laminate. In particular, it can be effectively used in display applications, etc., where the automation of protective film peeling is required and the size of the laminate is large.

11: Polymer solution (polymer solution or polymer precursor solution (polyamic acid solution)) 12: Inorganic substrate 13:Laminating roller 14: Protective film (1st protective film) 15: heat-resistant polymer film 16: Second protective film 41: flow meter 42: Gas introduction 43: Chemical solution tank (silane coupling agent tank) 44: warm water tank (water heating) 45: heater 46: Processing chamber (chamber) 47: Substrate 48: Exhaust port 51: Peel off auxiliary roller 62: Conveyor belt

Fig. 1 (a) is to coat the solution 11 such as polymer on the inorganic substrate 12, make the laminated body of inorganic substrate 12/heat-resistant polymer film 15, process by the protective film 14 attached on the surface of heat-resistant polymer film 15 An example of a procedure for a continuous sheet-like laminate. Fig. 1 (b) is coating solution 11 such as polymer on inorganic substrate 12, makes the laminated body of inorganic substrate 12/heat-resistant polymer film 15, by the protective film 14 that sticks on the surface of heat-resistant polymer film 15 and in This is an example of a procedure for processing the second protective film 16 on the surface opposite to the heat-resistant polymer film 15 of the inorganic substrate 12 into a continuous sheet-like laminate. Also, in order to distinguish it from the second protective film 16, the protective film 14 is referred to as a first protective film. FIG. 2 is a schematic diagram showing a cross-sectional structure of a stack of four stacked laminates (protective film 14/heat-resistant polymer film 15/inorganic substrate 12) of the present invention. The laminated system becomes a continuous sheet and is folded at each laminated body. 3 is a schematic diagram showing a stacked cross-sectional structure of four laminates of the present invention and a second protective film 16 (protective film 14/heat-resistant polymer film 15/inorganic substrate 12/second protective film 16). The laminated system including the second protective film is in the form of a continuous sheet, which is folded for each laminated body. FIG. 4 is a schematic view schematically showing an example of a silane coupling agent treatment apparatus used in the vapor deposition method in the present invention. Fig. 5 is a schematic diagram showing an example of a protective film peeling procedure in the present invention. FIG. 6 is an enlarged view of the peeling portion (near the peeling auxiliary roller 51 ) in FIG. 5 .

none.

Claims (7)

A laminate, which is a laminate comprising a protective film, a heat-resistant polymer film, and an inorganic substrate in sequence, characterized in that: the peel strength F1 of the 90° peel test between the inorganic substrate and the heat-resistant polymer film, The angle θ formed by the protective film and the heat-resistant polymer film when the protective film is peeled off from the heat-resistant polymer film, The tension T applied to the protective film, and The elastic modulus E of this protective film is Tsinθ＜F1 (1) and E＞2GPa (2). The laminate according to claim 1, wherein the F1 is in the range of 0.02 to 0.3 N/cm. The laminate according to claim 1 or 2, wherein the peel strength of the protective film and the heat-resistant polymer film in a 90° peel test is (1/3)×F1 or more. The laminate according to any one of claims 1 to 3, wherein the θ is 30° or less. The laminate according to any one of claims 1 to 4, wherein 0.2≦ETsinθ≦4 is satisfied. A peeling method, which is a method of peeling the protective film from a laminate sequentially comprising a protective film, a heat-resistant polymer film, and an inorganic substrate, characterized in that: The peel strength F1 of the 90° peel test between the inorganic substrate and the heat-resistant polymer film, The angle θ formed by the protective film and the heat-resistant polymer film when the protective film is peeled off from the heat-resistant polymer film, The tension T applied to the protective film, and The elastic modulus E of this protective film is Tsinθ＜F1 (1) and E＞2GPa (2). The peeling method according to claim 6, wherein there is a roller for assisting peeling of the protective film.