KR20170056543A - Laminate and method for manufacturing flexible device - Google Patents

Abstract

The present invention provides a laminate capable of separating a flexible substrate layer from an inorganic substrate with good adhesion between a heat-resistant resin film including a flexible substrate layer and an inorganic substrate and easily and in a short time. A laminate having an inorganic substrate (1) and a heat-resistant resin film (2) formed on the inorganic substrate, the laminate (100) having the following characteristics:
(1) A heat-resistant resin film (2) has a flexible substrate layer (21) and a sacrificial layer (22) provided on an outer edge portion of the flexible substrate layer;
(2) the bonding strength between the flexible substrate layer 21 and the inorganic substrate 1 is 2 N / cm or less;
(3) the bonding strength between the sacrificial layer 22 and the inorganic substrate 1 is more than 2 N / cm;
(4) The bonding strength between the sacrificial layer 22 and the inorganic substrate 1 is 2 N / cm or less by the post-treatment.

Description

TECHNICAL FIELD [0001] The present invention relates to a laminated body and a method of manufacturing a flexible device,

The present invention relates to a laminate having a heat-resistant resin film such as a polyimide-based resin formed on an inorganic substrate and a manufacturing method of the flexible device. The laminate of the present invention is useful, for example, in manufacturing a flexible device and a flexible wiring board in which an electronic element is formed on the surface of a flexible substrate.

2. Description of the Related Art In the field of electronic devices such as a flat panel display (FPD) such as a liquid crystal display (LCD), a plasma display panel (PDP), and an organic EL display (Inorganic substrate) having an electronic element formed thereon is used. However, since the inorganic substrate is rigid and lacks flexibility, there is a problem that it is difficult to be flexible.

Therefore, a method of using an organic polymer material such as polyimide having flexibility and heat resistance as a substrate has been proposed. That is, a technology has been put to practical use in which a heat-resistant resin film having flexibility is laminated on an inorganic substrate used as a carrier, and the heat-resistant resin film is used as a substrate or a wiring substrate for forming an electronic element. Here, for example, when a glass substrate having excellent light transmittance is used as an inorganic substrate, the inspection process at the time of forming an electronic element and at the time of forming a wiring board becomes easy, and an electronic device is formed on an existing glass substrate It is advantageous that the facility for producing a flexible device can be directly used.

In the inorganic substrate in which the flexible substrate layer made of such a heat-resistant resin film is laminated, since the inorganic substrate is used as the carrier substrate, an electronic element is formed on the surface of the heat-resistant resin film, It is necessary to separate them. Therefore, good releasability is required after the electronic device is formed. However, from the viewpoint of preventing the heat-resistant resin film from falling off from the inorganic substrate in the process of forming the electronic element, the heat-resistant resin film must be strongly adhered to the inorganic substrate. As a method for improving the adhesion, there has been proposed, for example, a method of treating the surface of an inorganic substrate such as a glass substrate with a silane coupler (Patent Documents 1 and 2). A method of roughening the surface of an inorganic substrate such as a glass substrate has also been proposed (Patent Documents 3 and 4). As a method for industrially carrying out peeling of a heat-resistant resin film firmly adhered to an inorganic substrate from an inorganic substrate as described above, for example, a method of irradiating a laser beam to the interface of a heat-resistant resin film such as a polyimide- (Patent Document 5); a method of heating an interface of a polyimide film in contact with a glass substrate by Joule heat (Patent Document 6); a method of induction heating (Patent Document 7); a flash light from a xenon lamp (Patent Document 8), or the like, a method of performing peeling is proposed. However, these methods have a problem in that the process is complicated and requires a long period of time, the cost is high because the equipment is expensive, and the reuse of the inorganic substrate is difficult.

As a peeling method instead of the above-mentioned method, Patent Document 9 proposes a method of improving the peeling property of a polyimide laminate by allowing it to stand in a pressurized steam for a long time. Patent Document 10 proposes a method of immersing in water to improve the peelability of the polyimide laminate. These methods utilize the fact that the stress caused by the rapid expansion of the polyimide film due to absorption (water absorption) or moisture absorption from the polyimide film surface acts on the interface between the polyimide film and the inorganic substrate. As a result, the adhesion at the interface is reduced and the peelability is improved.

International Publication WO 2010/071145 Specification International Publication WO 2011/030716 specification Japanese Patent Application Laid-Open No. H02-247633 Japanese Patent Laid-Open Publication No. 2013-149406 Japanese Patent Publication No. 2007-512568 Japanese Patent Laid-Open Publication No. 2012-189974 Japanese Patent Application Laid-Open No. 2014-86451 Japanese Patent Application Laid-Open No. 2014-120664 Japanese Patent Application Laid-Open No. 2000-196243 U.S. Patent No. 7575983

However, in the method using the moisture absorption or absorption described above, moisture absorption or absorption from the surface of the flexible substrate layer is utilized. For example, a gas barrier layer (a layer for preventing the permeation of water vapor and / , Which is a layer for preventing deterioration of an electronic device formed on a flexible substrate layer in an OLED or the like) is formed, moisture absorption or absorption is not sufficiently performed, so that there is a problem that sufficient peelability improvement effect can not be obtained there was. Further, there is a problem in that, in the method of leaving the film in the pressurized water vapor for a long time as disclosed in Patent Document 9, hydrolysis of the polyimide proceeds and deterioration of the film occurs.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a laminate capable of separating a flexible substrate layer from an inorganic substrate with good adhesion between a heat-resistant resin film including a flexible substrate layer and an inorganic substrate, And a method of manufacturing a flexible device using the laminate.

The present invention also provides a method for separating a flexible substrate layer from an inorganic substrate easily and in a short time even when a heat-resistant resin film including a flexible substrate layer and an inorganic substrate have good adhesion and a gas barrier layer is formed on the flexible substrate layer And a method of manufacturing a flexible device using the laminated body.

The present invention is also characterized in that the adhesion between the heat-resistant resin film including the flexible substrate layer and the inorganic substrate is good, and even if a member such as an electronic element or wiring is formed on the flexible substrate layer, A laminate capable of being separated from a substrate, and a method of manufacturing a flexible device using the laminate.

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above problems, and as a result, the inventors of the present invention have found that a laminate having a heat-resistant resin film formed on an inorganic substrate (hereinafter sometimes abbreviated as "laminate" And the present invention has been completed.

That is, the present invention has the following effect.

1. A laminate having an inorganic substrate and a heat-resistant resin film formed on the inorganic substrate, the laminate having the following characteristics:

(1) A heat-resistant resin film has a flexible substrate layer and a sacrificial layer provided on an outer edge portion of the flexible substrate layer;

(2) the bonding strength between the flexible substrate layer and the inorganic substrate is 2 N / cm or less;

(3) the bonding strength between the sacrificial layer and the inorganic substrate is more than 2 N / cm;

(4) The bonding strength between the sacrificial layer and the inorganic substrate is 2 N / cm or less by the post-treatment.

Wherein the heat-resistant resin is a polyimide-based resin.

And the post-treatment is a water absorption treatment.

Wherein a part of the inorganic substrate is previously subjected to the adhesion improving treatment and a sacrificial layer is formed on the surface on which the adhesion improving treatment is carried out.

Wherein the adhesion improving treatment is at least one of roughening treatment and silane coupling treatment.

After one or more members selected from electronic devices and wiring are formed on the surface of the flexible substrate layer of the heat-resistant resin film in the laminate, after the laminate is subjected to the post-treatment, the heat- And the flexible film is obtained by peeling off the resin film and then cutting off the portion of the sacrificial layer to obtain a flexible device.

Wherein at least one member selected from electronic elements and wiring is formed on the surface of the flexible substrate layer of the heat-resistant resin film in the laminate, and the heat-resistant resin film having the member is cut along the periphery of the flexible substrate layer A portion of the flexible substrate layer and the portion of the sacrifice layer in the heat-resistant resin film are divided, and then the portion of the flexible substrate layer in the heat-resistant resin film is peeled off to obtain a flexible device, And removing the thin film from the inorganic substrate and removing the thin film.

Wherein the gas barrier layer is formed before the member is formed on the surface of the flexible substrate layer.

In the laminate of the present invention, the flexible substrate layer can be easily peeled off without any treatment, while the sacrifice layer integrally formed on the outer edge of the flexible substrate layer can not be easily peeled off as it is, It is possible to peel off easily. For this reason, the flexible device and the flexible wiring board can be easily manufactured using this laminate.

1 (A) is a schematic view (cross-sectional view) of a laminate according to one embodiment of the present invention, and Fig. 1 (B) is a plan view of the laminate of Fig. 1 Fig.
2A and 2B are schematic diagrams (cross-sectional views) of a heat-resistant resin film for explaining an example of a method of manufacturing a flexible substrate using the laminate of Fig. 1A.
3 (A) and 3 (B) are schematic views (cross-sectional views) of a heat-resistant resin film for explaining another example of a method of manufacturing a flexible substrate using the laminate of Fig. 1 (A).

Hereinafter, the present invention will be described in detail.

[Laminate]

The laminate of the present invention is a heat resistant resin film formed on an inorganic substrate. As the inorganic substrate used herein, there is no limitation, such as a glass substrate, a metal substrate such as copper or aluminum, or a ceramic substrate such as alumina, but a glass substrate having excellent light transmittance is preferably used. As the glass substrate, for example, sodalime glass, borosilicate glass, non-alkali glass, or the like can be used, and among these, a non-alkali glass substrate can be preferably used.

The thickness of the inorganic substrate is preferably 0.3 to 5.0 mm. If the thickness is less than 0.3 mm, the handling properties of the substrate may be deteriorated. If the thickness is greater than 5.0 mm, the productivity may be lowered.

1 (A), the laminate 100 of the present invention has the heat-resistant resin film 2 laminated on the inorganic substrate 1, and the heat-resistant resin film 2 can be used as a flexible substrate And a sacrificial layer 22 provided on the outer edge of the flexible substrate layer 21. 1 (A) is a schematic view (cross-sectional view) of a laminate according to one embodiment of the present invention. Fig. 1B is a schematic schematic view of the inorganic substrate in the stacked body of Fig. 1 (A) when viewed from above. Fig.

The bonding strength between the sacrifice layer 22 and the inorganic substrate 1 is higher than the bonding strength between the flexible substrate layer 21 and the inorganic substrate 1 in the layered product 100. [ In order to achieve such a gradient of the adhesive strength, it is preferable that the surface of the inorganic substrate 1 in contact with the sacrificial layer 22 is subjected to the adhesion improving treatment described later. 1B is a region in which the sacrifice layer 22 is formed on the surface of the inorganic substrate 1, and the lattice region 220 in Fig. And the adhesion improving treatment is performed.

If the sacrifice layer 22 is not formed, the adhesion of the heat-resistant resin film 2 to the inorganic substrate 1 is reduced. Therefore, when an element such as an electronic element is formed on the heat-resistant resin film before the heat-resistant resin film is peeled from the inorganic substrate, the heat-resistant resin film is peeled off and the working efficiency is lowered.

The area of the sacrificial layer 22 is preferably 10% or more, more preferably 20% or less, more preferably 20% or more, Or more, and more preferably 50% or more. The upper limit value of the area of the sacrificial layer 22 is not particularly limited. However, from the viewpoint of reduction of material loss, the area of the sacrificial layer is usually less than 100%, preferably not more than 80% , And more preferably 60% or less. The area of the sacrificial layer is the area of the region where the sacrificial layer 22 is formed on the surface of the inorganic substrate 1 and the frame-like lattice region 220 (hereinafter referred to as " frame region " And there is a case where it is abbreviated). The area of the heat-resistant resin film is the area of the region where the resin film 2 is formed on the surface of the inorganic substrate 1.

1 (B), the sacrificial layer 22 forming region 220 has a frame shape, and the sacrificial layer 22 is formed on all of the outer edges of the flexible substrate layer 21. However, It is not necessarily the case that the sacrificial layer 22 should be formed on all of the outer edges of the flexible substrate layer 21. In the present invention, the sacrifice layer 22 may not be formed in a part of the outer edge of the flexible substrate layer 21 as long as the adhesion of the heat-resistant resin film 2 is ensured.

1 (A) and 1 (B), the heat-resistant resin film 2 has a square shape, but may have any shape depending on the shape of the flexible substrate layer 21 obtained from the laminate of the present invention. For example, it may have a circular shape or a rectangular shape. When the flexible substrate layer 21 is used as it is as a flexible substrate, the shape of the heat-resistant resin film 2 and the flexible substrate layer 21 is generally square or rectangular.

The width W1 (see Fig. 1 (B)) of the sacrificial layer 22 is usually 2 mm or more, particularly 2 mm or more and 100 mm or less, and preferably from the viewpoint of better balance of adhesion and releasability of the heat- Is not less than 3 mm and not more than 80 mm, and more preferably not less than 4 mm and not more than 50 mm.

The width W2 (see FIG. 1B) of the flexible substrate layer 21 may be determined according to the dimensions of a desired flexible substrate or flexible device, and is usually 10 to 300 mm. Preferably 100 to 200 mm, from the viewpoint of better balance of the characteristics.

The bonding strength of the flexible substrate layer 21 to the inorganic substrate 1 is 2 N / cm or less, preferably 1 N / cm or less, and more preferably 0.5 N / cm or less. By having such a bonding strength of the flexible substrate layer, it is possible to secure good releasability of the flexible substrate layer and the inorganic substrate. If the bonding strength between the flexible substrate layer and the inorganic substrate exceeds 2 N / cm, it is difficult to separate the flexible substrate layer from the inorganic substrate. The lower limit of the bonding strength of the flexible substrate layer to the inorganic substrate is not particularly limited, and the lower the better, the better. The bonding strength of the flexible substrate layer to the inorganic substrate is usually 0 N / cm or more.

The bonding strength of the sacrificial layer 22 to the inorganic substrate 1 is more than 2 N / cm, preferably 3 N / cm or more, and more preferably 4 N / cm or more. Since the sacrificial layer has such an adhesive strength, good adhesion between the sacrificial layer and the inorganic substrate can be ensured, so that the adhesion of the entire heat-resisting resin film including the sacrificial layer to the inorganic substrate can be secured. When the adhesive strength is 2 N / cm or less, when a member such as an electronic element is formed on the flexible substrate layer before the flexible substrate layer is separated from the inorganic substrate, the flexible substrate layer is peeled off and the working efficiency is lowered. The upper limit value of the bonding strength of the sacrificial layer to the inorganic substrate is not particularly limited, and the higher the higher the better. In order to secure such bonding strength, it is preferable that the surface of the frame region 220 of the inorganic substrate in contact with the sacrifice layer, for example, the glass substrate, is subjected to an adhesion improving treatment. By such a treatment, the bonding strength of the sacrifice layer increases. The adhesion strength of the sacrificial layer to the inorganic substrate is usually 50 N / cm or less, particularly 10 N / cm or less.

The adhesion improving treatment is a surface treatment of an inorganic substrate for improving the adhesion with the heat-resistant resin film (2). In the heat-resistant resin film formed on the inorganic substrate, the portion formed on the surface for improving the adhesion is the sacrifice layer (22). Therefore, the adhesion improving treatment is performed on the region where the sacrificial layer is desired to be formed on the inorganic substrate surface.

As the adhesion improving treatment, for example, at least one of a roughening treatment and a coupler treatment is performed. From the viewpoint of further improving the adhesion, the surface treatment is preferably carried out and then the coupler treatment is carried out.

As the roughening treatment, roughening of the inorganic substrate can be achieved by using a known treatment method as disclosed in, for example, Japanese Patent Application Laid-Open No. 2013-149406. Concretely, roughening can be performed by a chemical etching treatment, a polishing treatment, a sand blast treatment, a plasma treatment, a laser treatment, or the like. Since the surface area of the inorganic substrate is increased by the roughening treatment, an increase in the bonding strength is physically achieved. Chemical etching treatment is preferred among these roughening treatments.

In the chemical etching treatment, it is preferable to use an aqueous solution containing, for example, 0.5 to 8% by weight of hydrofluoric acid and perform etching treatment at 20 to 40 캜 for about 1 to 60 minutes.

The surface roughness (Ra based on JIS B 0601-1994) of the inorganic substrate subjected to the roughening treatment is preferably about 0.05 to 0.8 m.

In order to roughen only the portion forming the sacrifice layer on the surface of the inorganic substrate, the roughening treatment may be performed by masking the other portion with a release film or the like.

The coupler treatment is a treatment of applying an adhesion improving agent such as a coupler to the surface of an inorganic substrate to form a coat of a coupler. The coupler treatment chemically bonds the surface of the inorganic substrate with the heat-resistant resin film, in particular, the sacrificial layer via the coupler coating, so that an increase in adhesive strength is achieved.

As the coupler, a silane coupler, a titanium coupler, an aluminum coupler, or the like can be used, but a silane coupler treatment using a silane coupler is preferable.

The type of the silane coupler is not limited, and examples thereof include an amine type silane coupler, an epoxy type silane coupler, a vinyl type silane coupler, a styrene type silane coupler, a (meth) acrylic type silane coupler, A silane coupler, a mercapto silane coupler, a sulfide silane coupler, an isocyanate silane coupler, and an isocyanurate silane coupler. Specific examples include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, Aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3- 3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-isopropylpropyltriethoxy Amine-based silane coupling agents such as silane, aminophenyltrimethoxysilane, aminophenetel trimerethoxysilane, aminophenylaminomethylphenethyltrimethoxysilane, and the like; 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltri (3-glycidoxypropyltriethoxysilane), 3- Epoxy-based silane coupling agents such as ethoxy silane; Vinyl-based silane couplers such as vinyltriclorosilane, vinyltrimethoxysilane and vinyltriethoxysilane; styrene-based silane couplers such as p-styryltrimethoxysilane; Methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, (Meth) acrylic silane couplers such as 3-acryloxypropyltrimethoxysilane; Chloro-based silane coupling agents such as 3-chloropropyltrimethoxysilane, chloromethylphenethyltrimethoxysilane and chloromethyltrimethoxysilane; Mercaptoethyl silane couplers such as 3-mercaptopropyl methyl dimethoxy silane and 3-mercaptopropyl trimethoxy silane; Sulfide-based silane coupling agents such as bis (triethoxysilylpropyl) tetrasulfide; Isocyanate-based silane couplers such as 3-isocyanate propyltriethoxysilane; And isocyanurate-based silane couplers such as tris- (3-trimethoxysilylpropyl) isocyanurate. Preferred among these are amine or epoxy silane couplers, especially N-2- (aminoethyl) -3-aminopropylmethyl dimethoxysilane, N-2- (aminoethyl) Aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) Amine-based silanes such as N- (1,3-dimethyl-butyryliden) propylamine, aminophenyltrimethoxysilane, aminophenetetrylmethoxysilane and aminophenylaminomethylphenethyltrimethoxysilane. In coupler; 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltri (3-glycidoxypropyltriethoxysilane), 3- And epoxy-based silane coupling agents such as ethoxy silane.

The silane coupler may be of one type, or a plurality of types may be used in combination. On the other hand, the bonding strength can be further increased by subjecting the surface of the roughened inorganic substrate to the silane coupling treatment.

In order to form the film of the silane coupler, the silane coupler may be dissolved in a solvent to form a solution, which is then applied to an inorganic substrate and dried. The solvent to be used is not limited, but amide solvents such as N-methyl-2-pyrrolidone (NMP), N, N-dimethylformamide (DMF), and N, N-dimethylacetamide Can be used to make. The silane coupling agent concentration of the silane coupler solution is preferably 0.5 to 5% by mass. The coating amount of the coupler is formed, it is preferable, more preferably a 100~500mg / m ² to a 10~1000mg / m ^2.

In order to perform the coupler processing only on the portion of the inorganic substrate surface where the sacrifice layer is to be formed, the other portion may be masked with a release film or the like to perform a coupler process.

The sacrificial layer 22 having the above-described bonding strength can be peeled off from the inorganic substrate by carrying out a post-treatment to be described later. The sacrificial layer exhibits adhesion strength as shown below, for example, after the moisture absorption treatment. The adhesion strength of the sacrificial layer after the post-treatment with the inorganic substrate is preferably 2 N / cm or less, more preferably 1 N / cm or less, more preferably 0.5 N / cm or less, and most preferably 0.1 N / cm or less. The sacrificial layer is bonded to the inorganic substrate with such low bonding strength by the post-treatment, so that the sacrificial layer can be easily peeled off from the inorganic substrate. If the adhesion strength of the sacrificial layer to the inorganic substrate after the post-treatment exceeds 2 N / cm, it is difficult to separate the sacrificial layer from the inorganic substrate. The lower limit of the adhesive strength of the sacrificial layer after the post-treatment with the inorganic substrate is not particularly limited, and the lower the better, the better. The adhesion strength of the sacrificial layer after the post-treatment with the inorganic substrate is usually 0 N / cm or more.

The adhesive strength referred to in the present invention refers to a value measured by carrying out a 180 deg. Peel test based on JIS K6854-2.

The present invention is not limited to the flexible substrate layer 21 and the sacrificial layer 22 made of the respective constituent materials prepared so as to achieve the predetermined bonding strength with the inorganic substrate, (22) are usually made of the same constituent material. When the flexible substrate layer 21 and the sacrifice layer 22 are made of the same constituent material as described below, the bonding strength between the flexible substrate layer 21 and the inorganic substrate 1 is selected by selecting the constituent material , And the bonding strength between the sacrificial layer 22 and the inorganic substrate 1 is controlled by selecting the constituent material and by performing the adhesion improving treatment.

The heat-resistant resin film 2 used for the flexible substrate layer 21 and the sacrifice layer 22 is a film of a heat-resistant resin. The heat-resistant resin is a resin having a glass transition temperature measured by DSC (differential scanning calorimetry) of 200 ° C or higher, and the glass transition temperature of the heat-resistant resin is preferably 300 ° C or higher, more preferably 350 ° C or higher. As the heat-resistant resin, a polyimide resin, a polysulfone resin, a polyether sulfone resin, a polyarylate resin and the like can be given. As the heat resistant resin, it is preferable to use a polyimide resin.

The polyimide resin is a resin having an imide bond in the main chain, and specific examples thereof include polyimide, polyamideimide and polyesterimide. However, the polyimide resin is not limited to these, and any resins having an imide bond in the main chain Resins can also be used. These resins are usually used alone, but they may be used in combination of two or more.

As the polyimide, a precursor polyimide or a solvent-soluble polyimide in which a polyimide precursor such as a polyamic acid dissolved in a solvent is thermally cured to form a polyimide can be used, and a precursor-type polyimide can be preferably used.

As the polyimide-based resin, it is preferable that the polyimide-based resin has 50 mol% or more of constituent units derived from an imide bond (provided that the total constituent units are 100 mol%).

As the polyimide resin, a commercially available product may be used. That is, for example, "U Imide AR", "U Imide AH", "U Imide BH", "U Imide CR", "U Imide CH" (Available from Shin-Etsu Chemical Co., Ltd.), polyamic acid type varnish (manufactured by Ube Kosan Co., Ltd.), solvent soluble poly Midvanish, Viromax HR-11NN (Toyobo Co.), and the like can be used.

The precursor polyimide is a polyimide precursor solution obtained by reacting tetracarboxylic acid and / or dianhydride, which is a starting material, with approximately equimolar amounts of diamine in a solvent, which is applied, dried, thermally cured (imidized) Layer can be obtained.

The reaction temperature for preparing the polyimide precursor solution is preferably -30 to 60 占 폚, more preferably -15 to 40 占 폚. In this reaction, the order of addition of the monomer and the solvent is not particularly limited, and any order may be used.

Examples of the tetracarboxylic acid and / or its dianhydride include pyromellitic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 3,3', 4,4'-benzophenonetetracarboxylic acid, 3 , 3 ', 4,4'-diphenylsulfone tetracarboxylic acid, 3,3', 4,4'-diphenyl ether tetracarboxylic acid, 2,3,3 ', 4'-benzophenone tetracarboxylic acid, 2,3 , 6,7-naphthalenetetracarboxylic acid, 1,4,5,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 3,3 ', 4,4'-diphenylmethane tetracarboxylic acid, (3,4-dicarboxyphenyl) propane, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, 3,4,9,10-tetracarboxyperylene, (1, 2-bis [4- (3,4-dicarboxyphenoxy) phenyl] hexafluoropropane, 1 , 2,3,4-cyclobutanetetracarboxylic acid, 1,2,4,5-cyclopentane tetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, Chloride [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic acid, or the like and / or a dianhydride group or as a mixture, but not limited to these.

Here, pyromellitic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid or dianhydride thereof is particularly preferably used.

Examples of diamines include p-phenylenediamine, m-phenylenediamine, 3,4'-diaminodiphenylether, 4,4'-diaminodiphenylether, 4,4'- Diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 2,2-bis [4- (4-aminophenoxy) phenyl] Bis (p-aminophenyl) propane, 2,2-bis (p-aminophenyl) propane, diisobutylphenylacetate, (p-aminophenoxy) benzene, 4,4'-bis (p-aminophenyl) hexafluoropropane, 1,5-diaminonaphthalene, diaminotoluene, diaminobenzotrifluoride, Bis (p-aminophenoxy) biphenyl, diaminoanthraquinone, 4,4'-bis (3-aminophenoxyphenyl) diphenylsulfone, 1,3-bis (anilino) hexafluoropropane, 1 , 4-bis (anilino) octafluoro Butene, 1,5-bis (anilino) decafluoropentane, 1,7-bis (anilino) tetradecafluoroheptane, 1,2-ethylene diamine, 1,3- , 1,4-butanediamine, 1,5-pentadianamine, 1,6-hexanediamine, 1,7-heptenedianamine, 1,8-octanediamine, 1,9- 1,4-diaminocyclohexane, trans-1,4-diaminocyclohexane, 1,4-diaminocyclohexane, 1,4-diaminocyclohexane, 1,4- Cis-trans-4,4'-diaminodicyclohexyl methane, trans-trans-4,4'-diaminocyclohexylamine, cis- 1,3-bis (aminoethyl) cyclohexane, trans-1,3-bis (aminoethyl) -cyclohexylmethane diisocyanate, Cyclohexane, 1,3-bis (aminoethyl) cyclohexane isomer mixture Water, cis-trans-4,4'-methylenebis (2-methylcyclohexylamine), trans-trans-4,4'-methylenebis (2-methylcyclohexylamine), 4,4'- 2-methylcyclohexylamine) isomer mixture, cis-cis-4,4'-diaminodicyclohexylenepropane, cis-trans-4,4'-diaminodicyclohexylenepropane, 4,4 ' -Diaminodicyclohexylenepropane, and the like can be used singly or as a mixture, but the present invention is not limited thereto.

Here, p-phenylenediamine, 4,4'-diaminodiphenyl ether and 2,2-bis [4- (4-aminophenoxy) phenyl] propane are particularly preferably used.

The solid content concentration of the polyimide precursor is preferably from 1 to 50 mass%, more preferably from 5 to 30 mass%. The polyamic acid solution may be partially imidized.

The viscosity of the polyimide precursor solution of the present invention at 25 캜 is preferably 1 to 150 Pa · s, more preferably 5 to 100 Pa · s.

The solvent used for the polyimide precursor solution is not limited as long as it is a solvent dissolving the polyimide precursor, and examples thereof include an amide-based solvent, an ether-based solvent, and a water-soluble alcohol-based solvent.

Specific examples of the amide-based solvent include N-methyl-2-pyrrolidone (NMP), N, N-dimethylformamide (DMF), and N, N-dimethylacetamide (DMAc).

Examples of the ethereal solvent include 2-methoxyethanol, 2-ethoxyethanol, 2- (methoxymethoxy) ethoxyethanol, 2-isopropoxyethanol, 2-butoxyethanol, tetrahydrofurfuryl alcohol, Diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monoethyl ether, tetraethylene glycol, 1-methoxy-2-propanol, 1- Dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, polyethylene glycol, polypropylene glycol, tetrahydrofuran, dioxane, 1,2-di Methoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and the like.

Examples of the water-soluble alcohol solvents include methanol, ethanol, 1-propanol, 2-propanol, tert-butyl alcohol, ethylene glycol, Diol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2-butene-1,4-diol, 2- 1,2,6-hexanediol, diacetone alcohol, and the like.

These solvents can be used by mixing two or more kinds. Among these solvents, particularly preferred examples thereof include N, N-dimethylacetamide and N-methyl-2-pyrrolidone as the sole solvent, and N, N-dimethylacetamide and N- Methyl-2-pyrrolidone, a combination of N-methyl-2-pyrrolidone and methanol, N-methyl-2-pyrrolidone and 2-methoxyethanol.

A method of manufacturing a heat-resistant resin film by using a polyimide precursor solution will be described. However, even when a resin other than the above-mentioned polyimide-based resin is used as the heat-resistant resin, It is clear that the heat-resistant resin film 2 having the layer 21 and the sacrificial layer 22 can be produced.

The polyimide precursor solution is coated on the inorganic substrate 1 subjected to the adhesion enhancement treatment in the frame region 220, dried, and thermally cured to imidize. The application region 230 of the polyimide precursor solution is the entire inner region including the frame region 220 in FIG. 1B but is a region including the entire inner region including the frame region 220, Or may be applied over the framed area 220. The term "drying" as used herein means reducing the amount of the solvent in the polyimide precursor solution by means of heating or the like. At this time, it is preferable to remove the solvent until the solid content concentration in the coating film becomes 50% by mass or more and 90% by mass or less. Any device can be used for drying, and a hot-air dryer is preferable, but infrared heating, electromagnetic induction heating, or the like may be used. For drying, a temperature range of 50 to 200 ° C is suitable. The term " thermosetting " as used herein refers to a step of converting a polyimide precursor into polyimide. For thermal curing, a temperature range of 300 to 450 캜 is suitable.

In order to obtain the above bonding strength, a polyimide precursor solution may contain a release agent such as higher fatty acids such as stearic acid and palmitic acid, and amides and / or metal salts thereof. Of these, stearic acid is preferred. The adhesive strength of the flexible substrate layer and the sacrifice layer of the heat-resistant resin film becomes smaller as the compounding amount of the releasing agent is greater. On the other hand, the smaller the compounding amount of the releasing agent, the greater the adhesive strength of the flexible substrate layer and the sacrifice layer of the heat-resistant resin film.

The blending amount of the release agent in the polyimide precursor solution is not particularly limited as long as the flexible substrate layer and the sacrificial layer of the heat-resistant resin film can achieve a predetermined bonding strength, and usually 0.01 to 2 mass% of the polyimide precursor solution is added , More preferably from 0.1 to 1% by mass. In the present specification, the polyimide mass means the total mass of the polyimide in terms of the polyimide contained in the polyimide precursor solution.

To the polyimide precursor solution, an adhesion improver such as the silane coupling agent described above may be incorporated into the solution as necessary in order to obtain the above adhesive strength. The type of the silane coupler is not limited, but the amine-based or epoxy-based silane coupler described above is preferable. The greater the amount of the adhesion improver, the greater the adhesive strength of the flexible substrate layer and the sacrificial layer of the heat-resistant resin film. On the other hand, the bonding strength of the flexible substrate layer and the sacrifice layer of the heat-resistant resin film becomes smaller as the blending amount of the adhesion improver is smaller.

The blending amount of the adhesion improver in the polyimide precursor solution is preferably 0.05 to 0.5 mass%, more preferably 0.05 to 0.2 mass%, and even more preferably 0.1 to 0.2 mass% with respect to the mass of the polyimide.

The application of the polyimide precursor solution can be carried out continuously or sheet-by-sheet.

The continuous coating can be performed using a coating machine such as a die coater, a lip coater, a comma coater, a gravure coater, or a reverse roll coater.

The continuous coating may be performed using a coating machine such as a bar coater, a doctor blade coater, or a spin coater.

In this case, continuous coating is often accompanied by difficulty because the inorganic substrate is rigid. Therefore, from the standpoint of industrial production, coating on sheet is preferable.

The coating thickness of the heat-resistant resin film is preferably 5 to 200 占 퐉, more preferably 10 to 100 占 퐉, after heat curing. The thickness of the heat-resistant resin film is the thickness of the flexible substrate layer and the sacrifice layer, and the thickness of the flexible substrate layer and the sacrifice layer are equal.

As described above, in an electronic device using a heat-resistant resin film as a flexible substrate, a gas barrier layer is generally provided to prevent intrusion of water vapor or the like into the OLED light-emitting layer or the like. In the laminate used in the present invention, this gas barrier layer can be provided on the surface of the flexible substrate layer 21. [ As the gas barrier layer, a film composed of an inorganic oxide such as silicon oxide, aluminum oxide, silicon carbide, silicon oxycarbide, silicon carbide silicon nitride, silicon nitride, or silicon nitride oxide can be used, but a film made of silicon oxide is preferable. As a method for forming these films, known methods such as a sputtering method, a vacuum deposition method, a thermal CVD method, a plasma CVD method, and an optical CVD method can be mentioned, but a sputtering method is preferable. The thickness of the gas barrier layer is preferably 10 to 100 nm, more preferably 20 to 50 nm.

In the present invention, since the sacrifice layer 22 constituting the heat-resistant resin film 2 is strongly adhered to the inorganic substrate 1, the adhesion of the entire heat-resisting resin film 2 to the inorganic substrate 1 is ensured can do.

The heat-resistant resin film (2) of the present invention, particularly, the flexible substrate layer (21) is preferably transparent. The light transmittance at 500 nm, which is an index of transparency, is preferably 70% or more, and more preferably 80% or more.

[Manufacturing Method of Flexible Substrate or Flexible Device]

The laminated body 100 according to the present invention can easily peel the flexible substrate layer 21 and the sacrificial layer 22 from the inorganic substrate 1 by the unique structure and the post-processing to be described later. The peeled flexible substrate layer 21 is useful as a flexible substrate. At this time, before peeling at least the flexible substrate layer 21 in the laminate 100, at least one member selected from electronic elements and wirings (in this specification, simply referred to as "Quot; member ") is formed in advance so that the separated flexible substrate layer can be used as a flexible device. In the production of a flexible device, it is preferable to form the above-described gas barrier layer on the surface of the flexible substrate layer 21 before forming a member such as an electronic device.

A method of forming an element such as an electronic element can employ a known method in the field of an electronic device using a heat-resistant resin film as a flexible substrate.

The method of forming the gas barrier layer is the same as that described above.

(Embodiment 1)

First, the laminate 100 of the present invention is subjected to a post-treatment to be described later. Then, the heat-resistant resin film 2 is peeled off as shown in Fig. 2 (A). Specifically, as a method of peeling, a method of releasing from the end by hand and a method using a mechanical device such as a driving roll or a robot can be employed. Thereafter, a portion of the sacrificial layer 22 is cut off and removed to obtain a flexible substrate layer 21 as a flexible substrate (Fig. 2 (B)). 2 (A) and 2 (B) are schematic diagrams (cross-sectional views) of a heat-resistant resin film for explaining an example of a method of manufacturing a flexible substrate using the laminate of Fig. 1 (A).

The flexible substrate layer 21 obtained by preliminarily forming a member (not shown) such as an electronic element on the surface of the flexible substrate layer 21 of the layered product 100 before the post- It is useful as a device. It is preferable to form a gas barrier layer (not shown) on the surface of the flexible substrate layer 21 before formation of a member such as an electronic element.

(Embodiment 2)

First, a predetermined portion of the heat-resistant resin film is inserted to divide the portion of the flexible substrate layer 21 and the portion of the sacrifice layer 22 in the heat-resistant resin film. That is, as shown in Fig. 3 (A), a notch 200 is formed along the outer periphery 211 of the flexible substrate layer 21. The infeed 200 is not necessarily formed along the outer periphery 211 of the flexible substrate layer 21 and may be formed in the inner region of the flexible substrate layer 21 as long as a flexible substrate having a desired dimension can be obtained. The infeed method is not particularly limited as long as the infeed 200 reaching the inorganic substrate 1 can be formed. For example, a method using a commercially available cutter and a method using a laser light irradiation can be mentioned. 3 (A) and 3 (B) are schematic views (cross-sectional views) of a heat-resistant resin film for explaining another example of a method of manufacturing a flexible substrate using the laminate of Fig. 1 (A).

After dividing by the infeed 200 in Embodiment 2, the flexible substrate layer 21 is peeled off to obtain a flexible substrate as shown in Fig. 3 (B). As a specific method of peeling, also in this embodiment, a method of manually releasing from the end portion and a method using a mechanical device such as a driving roll or a robot can be adopted.

In the present embodiment 2, a flexible substrate (not shown) obtained by previously forming a member such as an electronic element (not shown) on the surface of the flexible substrate layer 21 of the heat-resistant resin film of the layered product 100, Layer is useful as a flexible device. Also in this embodiment, it is preferable to form a gas barrier layer (not shown) on the surface of the flexible substrate layer 21 before formation of a member such as an electronic element.

In Embodiment 2, the sacrificial layer 22 (FIG. 3 (B)) remaining on the inorganic substrate 1 can be removed from the inorganic substrate 1 by a post-treatment to be described later. As a method for peeling the sacrificial layer 22 specifically, a method of releasing the sacrificial layer 22 from the end by hand as described above, and a method using a mechanical device such as a driving roll or a robot may be employed.

[After treatment]

As a post-treatment method, it is preferable to use a water absorption treatment method. The water absorption treatment is treatment for causing volume expansion in the sacrifice layer 22 by moisture absorption or absorption treatment and lowering the bonding strength at the interface by stress at the interface due to the volume expansion. In the present invention, it is preferable that the sacrificial layer 22 be peeled off by water absorption treatment, in particular, moisture absorption treatment. However, as the post treatment, for example, the sacrificial layer 22 may be irradiated with laser light, And peeling may be performed by irradiating light or the like.

(Moisture absorption treatment)

The moisture absorption treatment includes a moisture absorption treatment step of holding at least the sacrificial layer under a high temperature and high humidity environment.

The moisture absorption conditions are not particularly limited, but preferably a moisture absorption process is carried out at a relative humidity of 70% or higher, more preferably 80% or higher, at a moisture absorption temperature of preferably 70 ° C or higher, more preferably 80 ° C or higher I do. Although pressurized steam exceeding 100 ° C may be used, it is preferable to carry out the moisture absorption treatment process at 100 ° C or lower. The moisture absorption treatment time is preferably 1 hour or more, more preferably 3 hours or more, and further preferably 5 hours or more. The upper limit of the moisture absorption treatment time is not particularly limited as long as the separation of the sacrificial layer is achieved, but the moisture absorption treatment step is usually conducted for 20 hours or less, preferably 15 hours or less, and more preferably 12 hours or less.

In this hygroscopic treatment, it is preferable to perform depressurization or dehumidification at normal pressure after the hygroscopic treatment step. The heat-resistant resin film whose volume has been expanded by moisture absorption can be rapidly shrunk by dehumidification. By this absorption and desorption operation, stress is generated in the sacrificial layer which expands or shrinks, and the strength at the interface of the sacrificial layer adjacent to the inorganic substrate, which hardly changes in volume due to absorption and desorption, is remarkably lowered. By this action, the sacrifice layer can be more easily peeled off. The absorption and desorption may be repeated two or more times to further improve the peelability. In the present invention, usually, the sacrificial layer can be easily peeled off by performing the sucking and dehumidifying process one to three times.

The decompression conditions include, but are not particularly limited to, decompression at a decompression degree of 100 Torr or less, more preferably 50 Torr or less, more preferably 10 Torr or less, temperature preferably 70 deg. C or more, Processing is performed. On the other hand, the temperature during the decompression treatment may be the same as or different from the above-mentioned moisture absorption treatment temperature. The decompression treatment time is preferably at least 1 hour, more preferably at least 3 hours, and more preferably at least 5 hours. The upper limit of the decompression treatment time is not particularly limited as long as the separation of the sacrifice layer is promoted, but the decompression treatment step is usually carried out for 20 hours or less, preferably 15 hours or less, and more preferably 12 hours or less.

(Absorption treatment)

The absorption treatment includes an absorption treatment process in which at least the sacrificial layer is immersed and held in a water bath.

The absorption conditions are not particularly limited, but the water temperature is preferably 20 ° C or more and 80 ° C or less, and more preferably 30 ° C or more and 60 ° C or less. The absorption treatment time is preferably 3 hours or more, more preferably 5 hours or more, and further preferably 10 hours or more. The upper limit of the absorption treatment time is not particularly limited as long as the separation of the sacrifice layer is achieved, but the absorption treatment process is usually carried out for 20 hours or less, preferably 15 hours or less, more preferably 12 hours or less.

In this absorption treatment, it is preferable to perform dehydration by drying under reduced pressure or atmospheric pressure after the above absorption treatment process. The sacrificial layer whose volume has been swollen by absorption can be rapidly shrunk by dehydration. By this absorption and dewatering operation, stress is generated in the sacrificial layer which expands or shrinks, and the strength at the interface of the sacrificial layer adjacent to the inorganic substrate, which does not substantially change in volume with the absorption dewatering, is remarkably lowered. By this action, the sacrifice layer can be more easily peeled off. This absorption water may be repeated two or more times to further improve the peelability. In the present invention, usually, the sacrificial layer can be easily peeled off by performing the absorption / desorption water one to three times.

The dehydration condition under the reduced pressure condition is not particularly limited, but preferably the decompression degree is 100 Torr or less, more preferably 50 Torr or less, still more preferably 10 Torr or less, the temperature is preferably 70 deg. C or more, more preferably 80 Deg. C or higher. On the other hand, the temperature at the time of the decompression treatment may be the same as or different from the above-mentioned absorption treatment temperature, but is preferably the same. The decompression treatment time is preferably at least 1 hour, more preferably at least 3 hours, and more preferably at least 5 hours. The upper limit of the decompression treatment time is not particularly limited as long as the peeling of the heat-resistant resin film 2 is promoted, but the decompression treatment step is usually conducted for 20 hours or less, preferably 15 hours or less, and more preferably 12 hours or less .

As described above, since the laminate of the present invention can easily peel off the sacrificial layer from the inorganic substrate by a simple post-treatment with a unique structure, it can be suitably used for manufacturing a flexible device and a flexible wiring board device have.

Example

Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.

[Referential Example 1]

U polyimide precursor solution obtained from U Imide AR (3,3 ', 4,4'-biphenyltetracarboxylic acid dianhydride and p-phenylenediamine), NMP as a solvent, 18% by mass) was prepared. This solution (referred to as polyimide solution A-1) was applied onto a surface of a 0.7 mm-thick smooth alkali-free glass plate (referred to as glass plate G-1) with a bar coater so that the thickness of the film after heat- , And dried at 130 DEG C for 10 minutes to form a polyimide precursor coating film. Then, the temperature was raised from 100 ° C to 360 ° C over 2 hours under a nitrogen gas stream, and then heat-treated at 360 ° C for 2 hours to thermally cure and imidize the polyimide precursor. Thus, a laminate L-1 having a glass substrate and a polyimide film layer having a thickness of 30 mu m was obtained.

[Reference Example 2]

The surface of the glass plate G-1 was dipped in an aqueous solution containing 5% by mass of hydrofluoric acid at 30 DEG C for 30 minutes to roughen the surface. The surface roughness Ra was 0.08 mu m. An NMP solution containing 2% by mass of a silane coupler (3-aminopropyltrimethoxysilane) was applied to the surface of the glass plate and dried to form a coating film of a silane coupler. Here, the coating amount of the silane coupler was 300 mg / m ² . Using this glass plate, a laminate L-2 having a glass substrate and a polyimide film layer having a thickness of 30 탆 was obtained in the same manner as in Reference Example 1.

[Referential Example 3]

A polyimide solution A-2 was obtained by adding a silane coupler (3-aminopropyltrimethoxysilane) to the polyimide solution A-1 in an amount of 0.05 mass% based on the mass of the polyimide and uniformly mixing. A laminate L-3 having a glass substrate and a polyimide film layer having a thickness of 30 占 퐉 was obtained in the same manner as in Reference Example 1 except that this was used.

[Reference Example 4]

A laminate L-4 having a glass substrate and a polyimide film layer having a thickness of 30 占 퐉 was obtained in the same manner as in Reference Example 2 except that the polyimide solution A-2 was used.

≪ Evaluation of adhesion &

The adhesive strength between the glass substrate and the heat-resistant resin film layer of the laminate L-1 to L-4 was measured by a 180 ° peel test based on JIS K6854. In addition, when the edge of the polyimide film of the laminate is inserted and the film can not be easily peeled off from the glass plate by pulling it therefrom, the adhesion at the interface is " good " Bad ". The results are shown in Table 1. On the other hand, in Table 1, when the bonding strength is 0.1 N / cm or less, it is difficult to specify the exact bonding strength.

As shown in Table 1, the laminate L-2 and L-4 had good adhesion. On the other hand, the laminate L-1 and L-3 had poor adhesion, that is, good peelability.

≪ Evaluation of peelability (post-treatment) >

The laminated films L-2 and L-4 having good adhesion were kept at a relative humidity of 95% and a temperature of 90 캜 for 10 hours to absorb the polyimide film. Thereafter, a decompression treatment was performed at a reduced pressure of 5 Torr for 10 hours at the same temperature to desorb the moisture-absorbing polyimide. The adhesion strength between the layers of the resulting laminate was measured by a 180 占 peel test based on JIS K6854. When the peelability at the interface is "good" and the peelability at the interface is not easily detachable, it is determined that the peelability is "poor" did. The results are shown in Table 2. On the other hand, in Table 2, when the bonding strength is 0.1 N / cm or less, it is difficult to specify the exact bonding strength, and therefore, it is expressed as " 0.1 or less ".

As shown in Table 2, the layered products L-2 and L-4, which had good adhesion before the moisture absorption treatment, can be made into a laminated product having good releasability by carrying out moisture absorption treatment.

[Example 1]

Only the frame region 220 of the non-alkali glass plate 1 having a thickness of 0.7 mm is subjected to an etching treatment and a silane coupling treatment in the same manner as in Reference Example 2 to improve adhesion only to the frame region 220 Whereby a glass plate G-3 subjected to the treatment was obtained. The area of the coated area 230 including the frame area 220 is about 576 cm ² (i.e., the width W 1 of the frame area 220 is 4 cm) W3) × 24 cm (W3), and the area of the flexible substrate layer formation region 210 not including the frame region 220 is set to about 400 cm ² . The polyimide solution A-1 similar to that of Reference Example 1 was applied to the application region 230 (about 576 cm ² ) of the coated glass plate G-3 including the frame region 220, 30 탆 by a bar coater, and dried at 130 캜 for 10 minutes to form a polyimide precursor coating film. Then, the temperature was raised from 100 ° C to 360 ° C over 2 hours under a nitrogen gas stream, and then heat-treated at 360 ° C for 2 hours to thermally cure the polyimide precursor to imidize the polyimide layer, Thereby obtaining laminate M-1.

[Example 2]

A laminate M-2 was obtained in the same manner as in Example 1 except that polyimide solution A-1 was used as polyimide solution A-2.

[Example 3]

3 (A), the inserting 200 is inserted along the outer periphery 211 of the flexible substrate layer 21 in the stacked bodies M-1 and M-2, and the flexible substrate layer 21 and the sacrifice The layer 22 was divided. A portion of the outer periphery 211 of the divided flexible substrate layer 21 is pulled by hand so that the flexible substrate layer 21 can be easily peeled off from the glass substrate 1 as shown in Fig. I could. Then, the sacrificial layer 22 was held by holding the glass substrate 1 (see Fig. 3B) in which the sacrificial layer 22 remained at a relative humidity of 85% and a temperature of 80 캜 for 8 hours . Thereafter, the dried polyimide was dried at 100 ° C under atmospheric pressure for 2 hours to dehumidify the moisture-absorbing polyimide, so that the sacrificial layer 22 could be easily peeled off by hand by both of the laminate M-1 and M-2.

[Example 4]

The laminated films M-1 and M-2 were held at a relative humidity of 95% and a temperature of 90 占 폚 for 10 hours to absorb moisture of the polyimide film (2). Thereafter, a decompression treatment was performed at a reduced pressure of 5 Torr for 10 hours at the same temperature to desorb the moisture-absorbing polyimide film (2). A part of the outer periphery of the polyimide film 2 was pulled by hand so that the polyimide film 2 could be easily peeled off from the glass substrate 1 as shown in Fig. Thereafter, a portion of the sacrificial layer 22 was cut off and removed to obtain a flexible substrate layer 21.

As described above, in the laminate of the present invention, the heat-resistant resin film 2 is firmly adhered on the inorganic substrate 1, and the sacrifice layer 22 is formed, for example, The flexible substrate layer 21 can be easily obtained and the inorganic substrate 1 can be easily reused. Therefore, the laminate of the present invention is useful for manufacturing a flexible substrate for an electronic device. Even when the gas barrier layer is formed on the surface of the heat-resistant resin film (2), particularly the flexible substrate layer (21) constituting the laminate, the production method of the present invention is excellent in adhesion before the post-treatment, All are good. Therefore, a flexible device and a flexible wiring board in which members such as electronic elements are formed on the flexible substrate layer 21 as a flexible substrate can be easily manufactured.

1: inorganic substrate
2: Heat-resisting resin film
21: Flexible substrate layer
210: Flexible substrate layer formation region
211: Outer periphery of the flexible substrate layer
22: sacrificial layer
220: frame region (sacrificial layer forming region)

Claims (8)

1. A laminate having an inorganic substrate and a heat-resistant resin film formed on the inorganic substrate, the laminate having the following characteristics:
(1) A heat-resistant resin film has a flexible substrate layer and a sacrificial layer provided on an outer edge portion of the flexible substrate layer;
(2) the bonding strength between the flexible substrate layer and the inorganic substrate is 2 N / cm or less;
(3) the bonding strength between the sacrificial layer and the inorganic substrate is more than 2 N / cm;
(4) The bonding strength between the sacrificial layer and the inorganic substrate is 2 N / cm or less by the post-treatment. The method according to claim 1,
Wherein the heat-resistant resin is a polyimide-based resin. The method according to claim 1,
And the post-treatment is a water absorption treatment. 4. The method according to any one of claims 1 to 3,
Wherein a part of the inorganic substrate is previously subjected to the adhesion improving treatment and a sacrificial layer is formed on the surface on which the adhesion improving treatment is carried out. 5. The method of claim 4,
Wherein the adhesion improving treatment is at least one of roughening treatment and silane coupling treatment. A method for manufacturing a heat-resistant resin film, comprising: forming at least one member selected from electronic elements and wiring on a surface of a flexible substrate layer of a heat-resistant resin film in the laminate according to any one of claims 1 to 5; Wherein the heat resistant resin film having the member is peeled off from the inorganic substrate and then the sacrifice layer is cut off to obtain a flexible device. A multilayered product according to any one of claims 1 to 5, wherein at least one member selected from electronic elements and wiring is formed on the surface of the flexible substrate layer of the heat-resistant resin film, The portion of the flexible substrate layer and the portion of the sacrifice layer in the heat-resistant resin film are divided, and then the portion of the flexible substrate layer in the heat-resistant resin film is peeled off to form a flexible And removing the sacrificial layer from the inorganic substrate by post-treating the sacrificial layer to obtain a device. 8. The method according to claim 6 or 7,
Wherein the gas barrier layer is formed before the member is formed on the surface of the flexible substrate layer.

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