JP2014237270A - Polymer film laminated substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymer film laminated substrate which allows stable peeling of a polymer film from an inorganic substrate through a small and constant force.SOLUTION: A polymer film laminated substrate includes a thin film formed continuously or discontinuously in a part of at least one side of an inorganic substrate, a silane coupling agent layer formed continuously or discontinuously on the thin film and a polymer film layer laminated on the silane coupling agent layer. The difference between the contact angle of the surface of the inorganic substrate to isopropyl alcohol and the contact angle of the surface of the thin film to isopropyl alcohol is 5 degrees or smaller. The surface on which the polymer film is laminated consists of an easily peelable part and a good adhesion part, and the adhesion strength of the inorganic substrate to the polymer film in the good adhesion part is at least twice the adhesion strength of the inorganic substrate to the polymer film in the easily peelable part.

Description

  The present invention is a polymer film laminated substrate having a thin film between an inorganic substrate and a polymer film layer (hereinafter also referred to as “polymer film”), and is useful for producing a flexible electronic device. Further, the present invention relates to a polymer film laminated substrate excellent in recyclability of an inorganic substrate.

  In recent years, for the purpose of reducing the weight, size and thickness of functional elements such as semiconductor elements, MEMS elements, and display elements, and increasing flexibility, technological developments for forming these elements on polymer films have been actively conducted. That is, as a material for the base material of electronic parts such as information communication equipment (broadcast equipment, mobile radio, portable communication equipment, etc.), radar, high-speed information processing equipment, etc., conventionally, it has heat resistance and information communication equipment signals. Ceramics that can cope with higher frequency bands (up to the GHz band) have been used, but since ceramics are not flexible and difficult to reduce in thickness, there is a drawback that applicable fields are limited. A polymer film is used as a substrate.

  When functional elements such as semiconductor elements, MEMS elements, and display elements are formed on the surface of a polymer film, it is ideal to process them using a so-called roll-to-roll process that uses the flexibility of polymer films. It is said that. However, in the industry such as the semiconductor industry, the MEMS industry, and the display industry, a process technology for a rigid flat substrate such as a wafer base or a glass substrate base has been constructed so far. Therefore, in order to form a functional element on a polymer film using existing infrastructure, the polymer film is bonded to a rigid support made of an inorganic material such as a glass plate, a ceramic plate, a silicon wafer, or a metal plate. A process is used in which a desired element is formed thereon and then peeled off from the support.

  By the way, in a process of forming a desired functional element on a laminate in which a polymer film and an inorganic support are bonded together, the laminate is often exposed to high temperatures. For example, in the formation of a functional element such as polysilicon or an oxide semiconductor, a process in a temperature range of about 200 to 500 ° C. is required. Further, in the production of a low-temperature polysilicon thin film transistor, heating at about 450 ° C. may be required for dehydrogenation, and in the production of a hydrogenated amorphous silicon thin film, a temperature of about 200 to 300 ° C. is applied to the film. There is a case. Therefore, although heat resistance is calculated | required for the polymer film which comprises a laminated body, the polymer film which can be practically used in this high temperature range is limited as a real problem. In addition, it is generally considered to use a pressure-sensitive adhesive or an adhesive for laminating the polymer film to the support, but the bonding surface of the polymer film and the support at that time (that is, an adhesive for laminating or the like) The adhesive also requires heat resistance. However, since a normal bonding adhesive or pressure-sensitive adhesive does not have sufficient heat resistance, bonding with an adhesive or pressure-sensitive adhesive cannot be applied when the functional element formation temperature is high.

  Since there is no heat-resistant adhesive means for attaching a polymer film to an inorganic substrate, in such applications, a polymer solution or a polymer precursor solution is applied onto an inorganic substrate and dried and cured on a support to form a film. Techniques used for such applications are known. However, since the polymer film obtained by such means is brittle and easily torn, the functional element formed on the surface of the polymer film often breaks when peeled from the support. In particular, it is extremely difficult to peel a large-area film from a support, and it is not possible to obtain a yield that is about industrially valid.

  In view of such circumstances, as a laminate of a polymer film and a support for forming a functional element, a polyimide film that has excellent heat resistance and is strong and can be thinned from an inorganic substance via a silane coupling agent. The laminated body bonded together to the support body (inorganic layer) which becomes is proposed (patent documents 1-3).

  By the way, the polymer film is originally a flexible material, and may be somewhat stretched or bent and stretched. On the other hand, the functional element formed on the polymer film often has a fine structure in which a conductor made of an inorganic material and a semiconductor are combined in a predetermined pattern, such as a minute expansion and contraction and bending extension. The structure is destroyed by the stress, and the characteristics as an electronic device are impaired. Such stress is likely to occur when the polymer film is peeled from the inorganic substrate together with the functional elements. Therefore, in the laminated body of patent documents 1-3, when peeling a polymer film from a support body, there exists a possibility that the structure of a functional element may be destroyed.

  Therefore, when a coupling agent treatment is performed on the inorganic substrate to form a coupling treatment layer, and then a part of the coupling treatment layer is subjected to an inactivation treatment, and the polyimide film is bonded to the inorganic substrate, Make a good adhesion part that is relatively difficult to peel off and an easy peel part that is relatively easy to peel off from the inorganic substrate, form a functional element on the easy peel part of the polyimide film, and cut the easy peel part of the polyimide film Thus, a technique has been proposed in which only the easy-peeling portion is peeled together with the functional element, so that the polyimide film can be peeled from the inorganic substrate in a state where stress applied to the functional element is reduced (Patent Document 4).

JP 2010-283262 A JP 2011-011455 A JP 2011-245675 A JP 2013-010342 A

  In Patent Document 4 described above, the laminate can be subjected to a process of directly forming a functional element on an inorganic substrate such as a conventional glass plate or silicon wafer, and further provided with a good adhesion portion and an easy peeling portion. Thus, the functional element formed on the polymer film can be relatively easily separated from the inorganic substrate together with the polymer film. Therefore, it is very useful when manufacturing a flexible electronic device. However, not all the problems have been solved even in the proposal of such technology.

  In the technology proposed in Patent Document 4, when an inactivation treatment is performed on an inorganic substrate coated with a coupling agent, and the activity of the coupling agent layer is changed, the well-bonded portion and the easily peelable portion are bonded. Since a difference in strength occurs, it is relatively easy to peel only the easily peelable portion. However, the adhesive strength within the easily peelable portion is not uniform and there is variation. In addition to the variation in the thickness of the coupling agent layer and the variation in the original activity of the coupling agent, such variation is coupled with the variation in the deactivation treatment of the coupling agent layer, Furthermore, the variation in the adhesive strength of the easily peelable portion will increase.

  Adhesion using a silane coupling agent is interpreted as a chemical reaction between the functional group of the silane coupling agent and the active point of the polymer film, but such chemical reaction is not only in the bonding process, Even when the functional element is formed on the polymer film after bonding, the chemical reaction state changes with the temperature, humidity, atmosphere, active energy dose, and the like, which affect the progress of adhesion. Chemical reactions include bonding and dissociation reactions, and both are intricately entangled in the reaction field. As a result, places with different degrees and forms of chemical reaction occur in the easily peelable portions, and the adhesive force is not uniform and varies in the easily peelable portions. Therefore, in the process of peeling the polymer film from the inorganic substrate, the functional element may be easily broken by a minute stress, and it is difficult to industrially produce an electronic device by this method.

  Further, when considering the industrial production of flexible electronic devices, the recyclability of the inorganic substrate, which is a temporary support, is an important issue that directly affects the manufacturing cost. The recyclability of the inorganic substrate greatly depends on the state of the inorganic substrate surface after the polymer film is peeled off.

  It is known that a silane coupling agent causes a chemical reaction with a hydroxyl group on the surface of an inorganic substrate, particularly a silicon wafer or a glass plate, and performs a strong covalent bond. Therefore, even if it is attempted to recycle the inorganic substrate with the silane coupling agent layer bonded to the surface remaining, the surface does not have the same properties as the surface of the original inorganic substrate. It is very difficult to apply the coupling agent uniformly. On the other hand, in order to completely remove the silane coupling agent layer, an effort equivalent to re-polishing the surface of the inorganic substrate is required, and the recycling cost of the inorganic substrate is increased. Therefore, it has been very difficult to recycle the inorganic substrate at a low cost.

  As a result of intensive studies to solve the above problems, the present inventors formed a thin film on at least one part of the surface of the inorganic substrate using a predetermined material, and applied a silane coupling agent on the thin film. By doing so, it was found that the silane coupling agent can be applied stably and uniformly. As a result, when the polymer film is laminated on the silane coupling agent layer, the polymer film can be easily peeled from the inorganic substrate together with the silane coupling agent layer at the easy peeling portion. As a result, a flexible electronic device with high accuracy can be produced with a high yield, and the recyclability of the inorganic substrate is also improved.

  That is, the present invention has the following configuration.

  In the present invention, a thin film is continuously or discontinuously formed on at least a part of one surface of an inorganic substrate, a silane coupling agent layer is continuously or discontinuously formed on the thin film, and further on the silane coupling agent layer. A polymer film laminated substrate in which a polymer film layer is laminated, wherein a difference between a contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate and a contact angle with respect to isopropyl alcohol on the surface of the thin film is within 5 degrees, and the polymer film is laminated. The cut surface is composed of an easily peelable portion that is an area where the polymer film can be easily separated from the inorganic substrate together with the silane coupling agent layer when a cut is made in the polymer film, and a good adhesive portion that is an area that cannot be easily separated. The adhesion strength between the inorganic substrate and the polymer film in the good adhesion part is the adhesion strength between the inorganic substrate and the polymer film in the easy peeling part. Characterized in that at least twice.

  It is preferable that the thin film contains at least one of Cr, noble metal, metal carbide, or metal nitride.

  It is preferable that the thin film is formed discontinuously on at least one surface of the inorganic substrate, the easy-peeling portion is covered with the thin film, and the good adhesion portion is not covered with the thin film.

  The polymer film is preferably a polyimide film.

  The polymer film laminated substrate according to the present invention is preferably used for temporarily supporting a polymer film material on an inorganic substrate when an electronic device (functional element) is formed on the polymer film.

  The present invention also includes a method for producing a flexible electronic device, which includes a step of forming a thin film continuously or discontinuously on at least part of one surface of an inorganic substrate, and a silane coupling agent layer on the thin film. Forming a continuous or discontinuous layer, laminating a plurality of polymer film layers on the silane coupling agent layer, adhering adjacent layers by heating and pressing, and a polymer film A step of forming an electronic device thereon, and a step of cutting the polymer film layer and peeling at least a part of the polymer film layer together with the electronic device and the silane coupling agent layer from the inorganic substrate. To do.

  In the above production method, a polymer solution or a polymer precursor solution is applied onto a silane coupling agent layer or a polymer film layer, and the applied solution is dried and heated to laminate the polymer film layer. Is preferred. Moreover, it is preferable to include the process of forming a predetermined pattern in a thin film.

  According to the present invention, by forming a thin film between a polymer film and an inorganic substrate, a silane coupling agent can be uniformly applied, and when the polymer film is peeled from the inorganic substrate, And, it becomes possible to peel with a certain low force. When the polymer film layer is peeled from the inorganic substrate, the polymer film layer can be peeled off from the inorganic substrate together with the silane coupling agent layer when the polymer film layer is cut, and the polymer film layer is not peeled off. In the case where the polymer film layer is removed from the inorganic substrate, only the component mainly composed of the silicate glass component remains on the inorganic substrate. Therefore, in the area of the well-bonded area (area where the thin film was not formed), after removal of the polymer film layer, the surface has a property close to the surface of the inorganic substrate, so re-application of the silane coupling agent is relatively easy. Thus, the recyclability of the inorganic substrate is greatly improved.

  Furthermore, according to the present invention, by forming the thin film into a predetermined pattern, the surface on which the polymer film is laminated is cut from the inorganic substrate together with the silane coupling agent layer when the polymer film is cut. It is possible to create an easily peelable area that is an easily separable area and a good adhesive area that is an area that cannot be easily separated, and make a cut along the periphery of the easily peelable area on the polymer film of the easily peelable area. The formed functional element portion can be peeled off from the inorganic substrate integrally with the polymer film.

  In the present invention, if a polymer film having high heat resistance is used, it is possible to bond the inorganic substrate and the polymer film without using an adhesive or pressure-sensitive adhesive that is inferior in heat resistance. Even if it is necessary, a functional element can be formed on the polymer film. In general, semiconductors, dielectrics, and the like can be expected to form higher-performance electronic devices because a thin film with better film quality is obtained when formed at a high temperature.

  Therefore, when the polymer film laminated substrate of the present invention is used, an electronic device such as a dielectric element, a semiconductor element, a MEMS element, a display element, a light emitting element, a photoelectric conversion element, a piezoelectric conversion element, and a thermoelectric conversion element is formed on the polymer film. It is useful for the production of flexible electronic devices formed in the above.

(Polymer film laminated substrate and manufacturing method thereof)
In the present invention, a thin film is continuously or discontinuously formed on at least a part of one surface of an inorganic substrate, a silane coupling agent layer is continuously or discontinuously formed on the thin film, and further on the silane coupling agent layer. This is a polymer film laminated substrate in which polymer film layers are laminated.

<Inorganic substrate>
In the present invention, an inorganic substrate is used as a support for the polymer film. In addition, when a flexible electronic device is manufactured by forming an electronic device on a polymer film, the inorganic substrate is used for temporarily supporting the polymer film material.

  The inorganic substrate may be any plate-like material that can be used as a substrate made of an inorganic substance, for example, a glass plate, a ceramic plate, a semiconductor wafer, a material mainly made of metal, etc., and these glass plates, ceramic plates, Examples of semiconductor wafers and metal composites include those obtained by laminating them, those in which they are dispersed, and those containing these fibers.

  Examples of the glass plate include quartz glass, high silicate glass (96% silica), soda lime glass, lead glass, aluminoborosilicate glass, borosilicate glass (Pyrex (registered trademark)), borosilicate glass (non-alkali), Borosilicate glass (microsheet), aluminosilicate glass and the like are included. Among these, those having a linear expansion coefficient of 5 ppm / K or less are desirable, and if it is a commercial product, “Corning (registered trademark) 7059” or “Corning (registered trademark) 1737” manufactured by Corning, which is a glass for liquid crystal, “EAGLE”, “AN100” manufactured by Asahi Glass, “OA10” manufactured by Nippon Electric Glass, “AF32” manufactured by SCHOTT, etc. are desirable.

Examples of the ceramic plate include Al ₂ O ₃ , Mullite, AlN, SiC, Si ₃ N ₄ , BN, crystallized glass, Cordierite, Spodumene, Pb—BSG + CaZrO ₃ + Al ₂ O ₃ , Crystallized glass + Al ₂ O ₃ z ed, Cry Ceramics for substrates such as BSG, BSG + Quartz, BSG + Al ₂ O ₃ , Pb + BSG + Al ₂ O ₃ , Glass-ceramic, Zerodur material, TiO ₂ , strontium titanate, calcium titanate, magnesium titanate, alumina, MgO, steatite, BaTi _{4 O 9, BaTiO 3, BaTi 4} + CaZrO 3, BaSrCaZrTiO 3, Ba (TiZr) O 3, PMN-PT and PFN-PF Capacitor materials _{such, PbNb 2 O 6, Pb 0.5} Be 0.5 Nb 2 O 6, PbTiO 3, BaTiO 3, PZT, 0.855PZT-95PT-0.5BT, 0.873PZT-0.97PT-0.3BT, PLZT And other piezoelectric materials.

  Although it does not specifically limit as said semiconductor wafer, Semiconductor wafers, such as a silicon wafer, a compound semiconductor wafer, etc. can be used.

  A silicon wafer is a product obtained by processing single crystal or polycrystalline silicon into a thin plate shape, and includes all silicon wafers doped with n-type or p-type, intrinsic silicon wafers, etc. Also included is a silicon wafer having a silicon oxide layer and various thin films deposited on its surface.

  Further, semiconductor wafers other than silicon wafers, compound semiconductor wafers, and the like can also be used as the semiconductor wafer. For example, germanium, silicon-germanium, gallium-arsenic, aluminum-gallium-indium, nitrogen-phosphorus-arsenic-antimony, SiC , InP (indium phosphorus), InGaAs, GaInNAs, LT, LN, ZnO (zinc oxide), CdTe (cadmium tellurium), ZnSe (zinc selenide) and the like.

  Examples of the metal include single element metals such as W, Mo, Pt, Fe, Ni, and Au, alloys such as inconel, monel, mnemonic, carbon copper, Fe-Ni invar alloy, and super invar alloy. In addition, a multilayer metal plate formed by adding other metal layers and ceramic layers to these metals is also included. In this case, if the overall linear expansion coefficient (CTE) with the additional layer is low, Cu, Al or the like is also used for the main metal layer. The metal used as the additional metal layer is limited as long as it has strong properties such as adhesion to the polymer film, no diffusion, and good chemical resistance and heat resistance. Although it is not a thing, Cr, Ni, TiN, Mo containing Cu etc. are mentioned as a suitable example.

  The planar portion of the inorganic substrate is desirably sufficiently flat. Specifically, the PV value of the surface roughness is 50 nm or less, more preferably 20 nm or less, and further preferably 5 nm or less. If it is coarser than this, the adhesive strength between the polymer film layer and the inorganic substrate may be insufficient.

  The thickness of the inorganic substrate is not particularly limited, but is preferably 10 mm or less, more preferably 3 mm or less, and even more preferably 1.3 mm or less from the viewpoint of handleability. The lower limit of the thickness is not particularly limited, but is preferably 0.07 mm or more, more preferably 0.15 mm or more, and further preferably 0.3 mm or more.

The area of the inorganic substrate is preferably a large area from the viewpoint of production efficiency and cost of the polymer film laminated substrate and the flexible electronic device. Specifically, it is preferably 1000 cm ² or more, more preferably 1500 cm ² or more, more preferably 2000 cm ² or more.

<Thin film>
In the present invention, a thin film is formed continuously or discontinuously on a part of at least one surface of the inorganic substrate. The following examples are described on the assumption that the polymer film is attached only to one side of the inorganic substrate, but the embodiment in which the polymer film is attached to both surfaces of the inorganic substrate is also within the scope of the present invention.

  The thin film contains at least one of Cr, noble metal, metal carbide, and metal nitride. In particular, when a glass plate or a silicon wafer is used as the inorganic substrate, it is preferable that at least one of Cr, noble metal, metal carbide, and metal nitride is included. The thin film is formed using a film formation source (evaporation source or target) containing at least one of Cr, noble metal, metal carbide, and metal nitride.

  When using Cr as the main film forming source, the film forming source preferably contains 90 mass% or more of Cr. Further, the element used in combination with Cr is not particularly limited as long as it is a transition metal element, but preferable examples include manganese, cobalt, vanadium, nickel, iron, molybdenum, and the like. These subcomponents can be used in combination with Cr within a range not exceeding 10 mass% of the film forming source.

  Examples of the noble metal include gold, silver, platinum, palladium, rhodium, iridium, ruthenium, and osmium. Among these, gold and platinum are preferably used. When a noble metal is used as the main film forming source, it is preferable that the film forming source contains at least one of the above metals in an amount of 85% by mass or more.

  The metal carbide means a metal carbide that is stable against water, and examples thereof include tungsten carbide, molybdenum carbide, titanium carbide, tantalum carbide, niobium carbide, vanadium carbide, zirconium carbide, silicon carbide, and boron carbide. Among them, it is preferable to use silicon carbide or boron carbide. When the metal carbide is the main film forming source, the film forming source preferably contains 80% by mass or more of metal carbide, more preferably 85% by mass or more, and still more preferably 90% by mass or more.

  Note that an alkali metal or alkaline earth metal carbide is not preferable because it may be decomposed by water.

  Examples of the metal nitride include titanium nitride, zirconium nitride, niobium nitride, tantalum nitride, chromium nitride, vanadium nitride, silicon nitride, gallium nitride, etc. Among them, titanium nitride, zirconium nitride, silicon nitride can be exemplified. It is preferable to use it. When metal nitride is used as the main film formation source, the film formation source preferably contains 80% by mass or more of metal nitride, more preferably 85% by mass or more, and further preferably 90% by mass or more. .

  The method for forming the thin film is not particularly limited, and known thin film forming means such as vapor deposition, sputtering, reactive sputtering, ion beam sputtering, and CVD can be used depending on the type and characteristics of the film forming source.

  A thin film can be formed using a vapor deposition source or target, but if the film formation source contains a plurality of substances such as a substance other than Cr, noble metal, metal carbide, or metal nitride, an alloy The thin film may be formed using a single vapor deposition source or target, or the thin film may be formed using a plurality of vapor deposition sources or targets without forming an alloy.

<Silane coupling agent treatment>
In the present invention, the silane coupling agent means a compound that is physically or chemically interposed between the inorganic substrate and the polymer film layer and has an action of increasing the adhesive force between the two.

  The coupling agent is not particularly limited, but a silane coupling agent having an amino group or an epoxy group is preferable. Preferable specific examples of the silane coupling agent include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- ( Aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, vinyltrichlorosilane, Vinyltrimethoxysilane, vinyltriethoxysila P-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyl Trimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane, 3-chloropropyl Trimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxy Orchid, tris- (3-trimethoxysilylpropyl) isocyanurate, chloromethylphenethyltrimethoxysilane, chloromethyltrimethoxysilane, aminophenyltrimethoxysilane, aminophenethyltrimethoxysilane, aminophenylaminomethylphenethyltrimethoxysilane, etc. Can be mentioned.

  In addition to the above, the silane coupling agent that can be used in the present invention includes n-propyltrimethoxysilane, butyltrichlorosilane, 2-cyanoethyltriethoxysilane, cyclohexyltrichlorosilane, decyltrichlorosilane, diacetoxydimethylsilane, Diethoxydimethylsilane, dimethoxydimethylsilane, dimethoxydiphenylsilane, dimethoxymethylphenylsilane, dodecyltrichlorosilane, dodecyltrimethoxysilane, ethyltrichlorosilane, hexyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrimethoxysilane, n-octyltri Chlorosilane, n-octyltriethoxysilane, n-octyltrimethoxysilane, triethoxyethylsilane, triethoxymethylsilane , Trimethoxymethylsilane, trimethoxyphenylsilane, pentyltriethoxysilane, pentyltrichlorosilane, triacetoxymethylsilane, trichlorohexylsilane, trichloromethylsilane, trichlorooctadecylsilane, trichloropropylsilane, trichlorotetradecylsilane, trimethoxypropyl Silane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, dimethoxymethylvinylsilane, trichlorovinylsilane, triethoxyvinylsilane, vinyltris (2-methoxyethoxy) silane, trichloro-2-cyanoethylsilane, diethoxy ( 3-glycidyloxypropyl) methylsilane, 3-glycidyloxypropyl (dimethoxy) ) Methylsilane, and the like can be used 3-glycidyloxypropyltrimethoxysilane.

  In the present invention, a silane coupling agent having one silicon atom in one molecule is particularly preferable. For example, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) ) -3-Aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N -(1,3-dimethyl-butylidene) propylamine, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane , 3-glycidoxypropyltriethoxysilane, aminophenyltrimethoxy Silane, amino phenethyltrimethoxysilane, such as aminophenyl aminomethyl phenethyltrimethoxysilane the like. In the case where particularly high heat resistance is required in the process, it is desirable to use an aromatic group between Si and an amino group.

  As a coupling agent that can be used in the present invention, a coupling agent other than the above-mentioned silane coupling agent can be used in combination. For example, 1-mercapto-2-propanol, methyl 3-mercaptopropionate, 3-mercapto-2-butanol, butyl 3-mercaptopropionate, 3- (dimethoxymethylsilyl) -1-propanethiol, 4- (6- Mercaptohexaloyl) benzyl alcohol, 11-amino-1-undecenethiol, 11-mercaptoundecylphosphonic acid, 11-mercaptoundecyltrifluoroacetic acid, 2,2 ′-(ethylenedioxy) diethanethiol, 11- Mercaptoundecyltri (ethylene glycol), (1-mercaptoundec-11-yl) tetra (ethylene glycol), 1- (methylcarboxy) undec-11-yl) hexa (ethylene glycol), hydroxyundecyl disulfide, carboxy Ndecyl disulfide, hydroxyhexadodecyl disulfide, carboxyhexadecyl disulfide, tetrakis (2-ethylhexyloxy) titanium, titanium dioctyloxybis (octylene glycolate), zirconium tributoxy monoacetylacetonate, zirconium monobutoxyacetylacetonate bis (Ethyl acetoacetate), zirconium tributoxy monostearate, acetoalkoxyaluminum diisopropylate, 3-glycidyloxypropyltrimethoxysilane, 2,3-butanedithiol, 1-butanethiol, 2-butanethiol, cyclohexanethiol, cyclo Pentanethiol, 1-decanethiol, 1-dodecanethiol, 2-ethylhexyl 3-mercaptopropionate, 3 Ethyl mercaptopropionate, 1-heptanethiol, 1-hexadecanethiol, hexyl mercaptan, isoamyl mercaptan, isobutyl mercaptan, 3-mercaptopropionic acid, 3-methoxybutyl 3-mercaptopropionate, 2-methyl-1-butanethiol, 1-octadecanethiol, 1-octanethiol, 1-pentadecanethiol, 1-pentanethiol, 1-propanethiol, 1-tetradecanethiol, 1-undecanethiol, 1- (12-mercaptododecyl) imidazole, 1- (11- Mercaptoundecyl) imidazole, 1- (10-mercaptodecyl) imidazole, 1- (16-mercaptohexadecyl) imidazole, 1- (17-mercaptoheptadecyl) imidazole, 1- (15-mercapto) dodecanoic acid, 1- (11-mercapto) undecanoic acid, 1- (10-mercapto) decanoic acid and the like can also be used.

<Method for forming silane coupling agent layer>
As a method for forming the silane coupling agent layer, a method of applying a silane coupling agent solution, a vapor deposition method, or the like can be used.

  As a method of applying the silane coupling agent solution, a solution obtained by diluting the silane coupling agent with a solvent such as alcohol is used, and a spin coating method, a curtain coating method, a dip coating method, a slit die coating method, a gravure coating method, a bar coating method, Conventionally known solution coating means such as a coating method, a comma coating method, an applicator method, a screen printing method, and a spray coating method can be appropriately used. When the method of applying the silane coupling agent solution is used, it is preferable to dry quickly after the application, and to perform a heat treatment at about 100 ± 30 ° C. for about several tens of seconds to 10 minutes. By the heat treatment, the silane coupling agent and the surface of the coated surface are bonded by a chemical reaction.

  The silane coupling agent layer can also be formed by vapor deposition. Specifically, the substrate is formed by exposing the substrate to vapor of the silane coupling agent, that is, a substantially gaseous silane coupling agent. The vapor of the silane coupling agent can be obtained by heating the silane coupling agent in a liquid state to a temperature from 40 ° C. to about the boiling point of the silane coupling agent. Although the boiling point of a silane coupling agent changes with chemical structures, it is the range of about 100-250 degreeC in general. However, heating at 200 ° C. or higher is not preferable because it may cause a side reaction on the organic group side of the silane coupling agent.

  The environment for heating the silane coupling agent may be under pressure, normal pressure, or reduced pressure, but is preferably under normal pressure or reduced pressure when promoting vaporization of the silane coupling agent. Since many silane coupling agents are flammable liquids, it is preferable to perform the vaporizing operation in an airtight container, preferably after replacing the inside of the container with an inert gas.

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

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

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

  In the present invention, it is preferable that the surface of the inorganic substrate on which the silane coupling agent layer is to be formed is held downward and exposed to the silane coupling agent vapor by vapor deposition. In the method of applying the silane coupling agent solution, the coating surface of the inorganic substrate is inevitably facing upward during and before coating, so it is impossible to deny the possibility of floating foreign substances, etc. in the working environment being deposited on the surface of the inorganic substrate. . However, the vapor deposition method can hold the surface of the inorganic substrate on which the silane coupling agent layer is to be formed facing downward, so that foreign substances in the environment can adhere to the surface of the inorganic substrate (or the surface of the thin film) or the surface of the silane coupling agent layer. The possibility of adhesion is reduced.

  In addition, it is preferable to clean the inorganic substrate surface before a silane coupling agent process by means, such as short wavelength UV / ozone irradiation, or a liquid cleaning agent.

  The film thickness of the silane coupling agent layer is extremely thin compared to inorganic substrates, polymer films, etc., and is negligible from a mechanical design standpoint. A thickness on the order of the molecular layer is sufficient. Generally, it is less than 400 nm, preferably 200 nm or less, more preferably 100 nm or less in practical use, more preferably 50 nm or less, and further preferably 10 nm or less. However, when the calculation is in the region of 5 nm or less, the silane coupling agent layer may exist in a cluster form, not as a uniform coating film. In addition, the film thickness of a silane coupling agent layer can be calculated | required from the ellipsometry method or calculating from the density | concentration and application amount of the silane coupling agent solution at the time of application | coating.

<Polymer film>
It is possible to form a polymer film layer by applying a polymer solution or a polymer precursor solution on an inorganic substrate on which a thin film and a silane coupling agent layer are formed, and drying and forming a film. .

  Examples of the polymer film in the present invention include aromatic polyimides such as polyimide, polyamideimide, polyetherimide, and fluorinated polyimide, polyimide resins such as alicyclic polyimide, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene-2. Copolyesters such as wholly aromatic polyesters and semi-aromatic polyesters such as 1,6-naphthalate, copolymerized (meth) acrylates represented by polymethyl methacrylate, polycarbonate, polyamide, polysulfone, polyethersulfone, polyetherketone, acetic acid Cellulose, cellulose nitrate, aromatic polyamide, polyvinyl chloride, polyphenol, polyarylate, polyphenylene sulfide, polyphenyleneoxy , It can be used a film of polystyrene, the film heat resistance using 100 ° C. or more polymeric, preferably a film using a so-called engineering plastics. The film using engineering plastic is preferably, for example, an aromatic polyester film, and further includes a super engineering plastic film such as an aromatic polyamide film, a polyamideimide film, or a polyimide film having a heat resistant temperature exceeding 150 ° C. Can do. Here, the heat resistance means a glass transition temperature or a heat distortion temperature.

  Details of the polyimide resin film will be described below. In general, a polyimide resin film is obtained by applying a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent to a support for preparing a polyimide film, followed by drying to obtain a green film (hereinafter, referred to as a polyimide film). It is also referred to as “polyamic acid film”), and it is obtained by subjecting the green film to high-temperature heat treatment on a support for preparing a polyimide film or in a state peeled from the support to cause a dehydration ring-closing reaction.

  There is no restriction | limiting in particular as diamine which comprises a polyamic acid, The aromatic diamine, aliphatic diamine, alicyclic diamine etc. which are normally used for a polyimide synthesis | combination can be used. From the viewpoint of heat resistance, aromatic diamines are preferable, and among aromatic diamines, aromatic diamines having a benzoxazole structure are more preferable. When aromatic diamines having a benzoxazole structure are used, it is possible to develop a high elastic modulus, a low heat shrinkage, and a low linear expansion coefficient as well as a high heat resistance. Diamines may be used alone or in combination of two or more.

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

Examples of the aromatic diamine other than the aromatic diamine having the benzoxazole structure described above include 2,2′-dimethyl-4,4′-diaminobiphenyl, 1,4-bis [2- (4-aminophenyl). ) -2-propyl] benzene (bisaniline), 1,4-bis (4-amino-2-trifluoromethylphenoxy) benzene, 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl, 4,4 '-Bis (4-aminophenoxy) biphenyl, 4,4'-bis (3-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl Sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (3-aminophenoxy) phenyl] propyl Pan, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl sulfide, 3,3′- Diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3 , 3'-diaminobenzophenone, 3,4'-diaminobenzo Zophenone, 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-amino) Phenoxy) phenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] butane, 1,3-bis [4- (4-aminopheno) Cis) 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-he Xafluoropropane, 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] sulfoxide, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether, 1,3-bis [4- ( 4-aminophenoxy) benzoyl] benzene, 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene, 1 , 4-Bis [4- (3-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) phenyl] sulfoxide, 4,4′-bis [3- (4-aminophenoxy) benzo Diphenyl ether, 4,4′-bis [3- (3-aminophenoxy) benzoyl] diphenyl ether, 4,4′-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzophenone, 4, 4′-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] diphenylsulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone, 1,4-bis [4 -(4-aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4 -(4-Amino-6-trifluoromethylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-fur) Olophenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-methylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- ( 4-amino-6-cyanophenoxy) -α, α-dimethylbenzyl] benzene, 3,3′-diamino-4,4′-diphenoxybenzophenone, 4,4′-diamino-5,5′-diphenoxybenzophenone 3,4′-diamino-4,5′-diphenoxybenzophenone, 3,3′-diamino-4-phenoxybenzophenone, 4,4′-diamino-5-phenoxybenzophenone, 3,4′-diamino-4- Phenoxybenzophenone, 3,4′-diamino-5′-phenoxybenzophenone, 3,3′-diamino-4,4′-dibiphenoxybenzophenone, 4,4′-dia No-5,5′-dibiphenoxybenzophenone, 3,4′-diamino-4,5′-dibiphenoxybenzophenone, 3,3′-diamino-4-biphenoxybenzophenone, 4,4′-diamino-5-bi Phenoxybenzophenone, 3,4'-diamino-4-biphenoxybenzophenone, 3,4'-diamino-5'-biphenoxybenzophenone, 1,3-bis (3-amino-4-phenoxybenzoyl) benzene, 1,4 -Bis (3-amino-4-phenoxybenzoyl) benzene, 1,3-bis (4-amino-5-phenoxybenzoyl) benzene, 1,4-bis (4-amino-5-phenoxybenzoyl) benzene, 1, 3-bis (3-amino-4-biphenoxybenzoyl) benzene, 1,4-bis (3-amino-4-biphenoxybenzoy) ) Benzene, 1,3-bis (4-amino-5-biphenoxy benzoyl) benzene, 1
, 4-bis (4-amino-5-biphenoxybenzoyl) benzene, 2,6-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzonitrile, and the aromatic ring of the above aromatic diamine Some or all of the above hydrogen atoms are substituted by halogen atoms, some or all of the hydrogen atoms of a halogen atom, an alkyl group having 1 to 3 carbon atoms or an alkoxyl group, a cyano group, or an alkyl group or alkoxyl group. An aromatic diamine substituted with a halogenated alkyl group having 1 to 3 carbon atoms or an alkoxyl group is exemplified.

  Examples of the aliphatic diamines include 1,2-diaminoethane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,8-diaminooctane, and the like.

  Examples of the alicyclic diamines include 1,4-diaminocyclohexane, 4,4′-methylenebis (2,6-dimethylcyclohexylamine), and the like.

  The total amount of diamines other than aromatic diamines (aliphatic diamines and alicyclic diamines) is preferably 20% by mass or less, more preferably 10% by mass or less, and still more preferably 5% by mass or less of the total diamines. It is. In other words, the aromatic diamine is preferably 80% by mass or more of the total diamines, more preferably 90% by mass or more, and still more preferably 95% by mass or more.

  The tetracarboxylic acids constituting the polyamic acid include aromatic tetracarboxylic acids (including acid anhydrides), aliphatic tetracarboxylic acids (including acid anhydrides), and alicyclic tetracarboxylic acids that are commonly used for polyimide synthesis. Acids (including acid anhydrides thereof) can be used. Among them, aromatic tetracarboxylic acid anhydrides and alicyclic tetracarboxylic acid anhydrides are preferable, aromatic tetracarboxylic acid anhydrides are more preferable from the viewpoint of heat resistance, and alicyclic from the viewpoint of light transmission. Group tetracarboxylic acids are more preferred. In the case where these are acid anhydrides, the number of anhydride structures in the molecule may be one or two, but those having two anhydride structures (dianhydrides) are preferred. Good. Tetracarboxylic acids may be used alone or in combination of two or more.

  Examples of the alicyclic tetracarboxylic acids include alicyclic tetracarboxylic acids such as cyclobutanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, and 3,3 ′, 4,4′-bicyclohexyltetracarboxylic acid. Carboxylic acids and their acid anhydrides are mentioned. Among these, dianhydrides having two anhydride structures (for example, cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ′, 4,4 '-Bicyclohexyltetracarboxylic dianhydride and the like) are preferred. In addition, alicyclic tetracarboxylic acids may be used independently and may use 2 or more types together.

  In the case where importance is attached to transparency, the alicyclic tetracarboxylic acids are, for example, preferably 80% by mass or more of all tetracarboxylic acids, more preferably 90% by mass or more, and further preferably 95% by mass or more.

  The aromatic tetracarboxylic acids are not particularly limited, but are preferably pyromellitic acid residues (that is, those having a structure derived from pyromellitic acid), and more preferably acid anhydrides thereof. Examples of such aromatic tetracarboxylic acids include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride, 3 , 3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride, 2,2-bis [4- (3,4-di Carboxyphenoxy) phenyl] propanoic anhydride and the like.

  In the case of placing importance on heat resistance, the aromatic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more of all tetracarboxylic acids.

  For example, spin coating, doctor blade, applicator, comma coater, screen printing method, slit coating, reverse coating, dip coating, curtain coating can be applied to the silane coupling agent layer. Conventionally known solution application means such as slit die coating can be appropriately used.

  For example, after applying a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent in a solvent to a predetermined thickness on an inorganic substrate and drying, It can be obtained by a thermal imidation method in which a dehydration ring-closing reaction is performed by heat treatment at high temperature or a chemical imidation method using acetic anhydride or the like as a dehydrating agent and pyridine or the like as a catalyst.

  In the case of a thermoplastic polymer, a polymer film layer can be obtained by a melt stretching method. Moreover, when it is not a thermoplastic polymer, a polymer film layer can be obtained by a solution casting method. Furthermore, depending on the polymer, a technique of applying a film of the polymer material itself or a precursor thereof onto the silane coupling agent layer and drying it to form a film can be used.

  The thickness of the polymer film of the present invention is preferably 3 μm or more, more preferably 11 μm or more, still more preferably 24 μm or more, and even more preferably 45 μm or more. The upper limit of the thickness of the polymer film is not particularly limited, but is preferably 250 μm or less, more preferably 150 μm or less, and still more preferably 90 μm or less for use as a flexible electronic device.

  The polymer film of the present invention preferably has a glass transition temperature of 250 ° C. or higher, preferably 300 ° C. or higher, more preferably 350 ° C. or higher, or no glass transition point observed in the region of 500 ° C. or lower. The glass transition temperature in the present invention is determined by differential thermal analysis (DSC).

  The average CTE of the polymer film of the present invention between 30 ° C. and 300 ° C. is preferably −5 ppm / ° C. to +20 ppm / ° C., more preferably −5 ppm / ° C. to +15 ppm / ° C., and further preferably Is 1 ppm / ° C. to +10 ppm / ° C. When the CTE is in the above range, the difference in linear expansion coefficient from a general support (inorganic substrate) can be kept small, and the polymer film and the inorganic substrate can be peeled off even when subjected to a process of applying heat. Can be avoided.

  The tensile strength at break of the polymer film in the present invention is preferably 60 MPa or more, more preferably 120 MPa or more, and further preferably 240 MPa or more. The upper limit of the tensile strength at break is not particularly limited, but is practically less than about 1000 MPa. The tensile breaking strength of the polymer film refers to the average value of the tensile breaking strength in the flow direction (MD direction) and the tensile breaking strength in the width direction (TD direction) of the polymer film.

The thickness unevenness of the polymer film in the present invention is preferably 20% or less, more preferably 12% or less, still more preferably 7% or less, and particularly preferably 4% or less. When the thickness unevenness exceeds 20%, it tends to be difficult to apply to narrow portions. In addition, the thickness unevenness of a film can be calculated | required based on the following formula, for example, extracting about 10 points | pieces positions from a film to be measured at random with a contact-type film thickness meter, measuring film thickness.
Film thickness spots (%)
= 100 × (maximum film thickness−minimum film thickness) ÷ average film thickness

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

  In the case of using a polymer film particularly for the production of a flexible display element, it is preferable to use a polyimide resin film having colorless transparency, but in the case of forming a back element of a reflective or self-luminous display, This is not the case.

  In the polymer film, in order to ensure handling and productivity, a lubricant (particle) is added to and contained in the polymer film, and the polymer film surface is provided with fine irregularities to ensure slipperiness. It is preferable. The lubricant (particle) is a fine particle made of an inorganic substance, and includes metal, metal oxide, metal nitride, metal carbonized product, metal acid salt, phosphate, carbonate, talc, mica, clay, and other clay minerals. Or the like. Preferably, metal oxides such as silicon oxide, calcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, calcium pyrophosphate, hydroxyapatite, calcium carbonate, glass filler, phosphates, and carbonates can be used. Only one type of lubricant may be used, or two or more types may be used.

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

  The addition amount of the lubricant is 0.02 to 5% by mass, preferably 0.04 to 1% by mass, more preferably 0.08 to 0.00% as the addition amount with respect to the polymer component in the polymer film. 4% by mass. If the amount of lubricant added is too small, it is difficult to expect the effect of lubricant addition, and there is a case where the slipperiness is not sufficiently secured, which may hinder the production of polymer film. Even if the slipperiness is ensured, the smoothness may be lowered, the breaking strength or breaking elongation of the polymer film may be lowered, or the CTE may be raised.

  When a lubricant (particles) is added to and contained in a polymer film, a single-layer polymer film in which the lubricant is uniformly dispersed may be used. For example, one surface may be a polymer film containing a lubricant. It is good also as a multilayer polymer film comprised by the polymer film which is comprised and the other surface does not contain a lubricant, or contains the lubricant, even if it contains a lubricant. In such a multilayer polymer film, fine unevenness is given to the surface of one layer (film) to ensure slipperiness with this layer (film), ensuring good handling properties and productivity. it can.

  When a multilayer polymer film is produced by a melt-stretching film-forming method, for example, a large amount of lubricant is formed on a film formed of a polymer-containing solution that does not contain or contains a small amount of lubricant. It can be obtained by applying and laminating a polymer-containing solution. Of course, conversely, it is obtained by applying and laminating a polymer-containing solution containing no lubricant or a small amount on a film formed of a polymer-containing solution containing a lubricant. You can also.

  The same applies to a polymer film such as a polyimide film obtained by using a solution casting method. For example, as a polyamic acid solution (a polyimide precursor solution), a lubricant (preferably an average particle size of 0.05 to About 2.5 μm) to 0.02 mass% to 50 mass% (preferably 0.04 to 3 mass%, more preferably 0.08 to 1.2 mass%) based on the polymer solid content in the polyamic acid solution. Containing polyamic acid solution and no lubricant or a small amount thereof (preferably less than 0.02% by mass, more preferably less than 0.01% by mass with respect to polymer solids in the polyamic acid solution) Can be produced using two types of polyamic acid solutions.

  The method of multilayering (lamination) of the multilayer polymer film is not particularly limited as long as no problem occurs in the adhesion between both layers, and any method may be used as long as the adhesion is achieved without using an adhesive layer or the like.

  When the polymer film is a polyimide film, for example, i) after one polyimide film is produced, the other polyamic acid solution is continuously applied onto the polyimide film and imidized, and ii) one polyamic acid After casting the solution to produce a polyamic acid film, the other polyamic acid solution is continuously applied onto the polyamic acid film and then imidized, iii) a method by coextrusion, iv) does not contain a lubricant Or the method of apply | coating the polyamic acid solution which contains many lubricants by spray coating, T-die coating, etc. on the film formed with the polyamic acid solution whose content is a small amount can be illustrated. In the present invention, it is preferable to use the methods i) to ii).

  The ratio of the thickness of each layer in the multi-layer polymer film is not particularly limited, but the polymer layer containing a large amount of the lubricant (a) is a layer, the polymer does not contain the lubricant or the content thereof is small. When the layer is the (b) layer, the (a) layer / (b) layer is preferably 0.05 to 0.95. If the (a) layer / (b) layer exceeds 0.95, the smoothness of the (b) layer tends to be lost. On the other hand, if it is less than 0.05, the effect of improving the surface properties is insufficient and the slipperiness is lost. May be.

<Surface activation treatment of polymer film>
The polymer film used in the present invention is preferably subjected to a surface activation treatment. By subjecting the polymer film to surface activation treatment, the surface of the polymer film is modified to a state in which a functional group exists (so-called activated state), and adhesion to the inorganic substrate is improved.

  The surface activation treatment in the present invention is a dry or wet surface treatment. Examples of the dry surface treatment include vacuum plasma treatment, atmospheric pressure plasma treatment, treatment of irradiating the surface with active energy rays such as ultraviolet rays, electron beams, and X-rays, corona treatment, flame treatment, and intro treatment. it can. Examples of the wet surface treatment include a treatment in which the polymer film surface is brought into contact with an acid or alkali solution.

  In the present invention, a plurality of surface activation treatments may be combined. Such surface activation treatment cleans the surface of the polymer film and generates more active functional groups. The generated functional group is bonded to the silane coupling agent layer by hydrogen bonding or chemical reaction, and the polymer film layer and the silane coupling agent layer can be firmly bonded.

  Moreover, the effect of etching the polymer film surface can also be obtained by performing plasma treatment. In particular, in a polymer film containing a relatively large amount of lubricant particles, protrusions due to the lubricant may inhibit the adhesion between the polymer film and the inorganic substrate. In this case, it is possible to remove the lubricant particles in the vicinity of the polymer film surface by etching the polymer film surface thinly by plasma treatment to expose a part of the lubricant particles and then treating with hydrofluoric acid. It is.

  The surface activation treatment preferably used in the present invention is a combination of a plasma treatment which is a dry surface treatment and a treatment which is brought into contact with an acid solution which is a wet surface treatment.

  The plasma treatment is not particularly limited, but includes RF plasma treatment in vacuum, microwave plasma treatment, microwave ECR plasma treatment, atmospheric pressure plasma treatment, corona treatment, etc., gas treatment containing fluorine, ion Includes ion implantation using a source, treatment using PBII, flame treatment exposed to thermal plasma, and intro treatment. Among these, RF plasma treatment, microwave plasma treatment, and atmospheric pressure plasma treatment in vacuum are preferable.

Appropriate conditions for the plasma treatment include oxygen plasma, plasma containing fluorine such as CF ₄ and C ₂ F _6, plasma known to have a high etching effect, or physical energy such as Ar plasma. It is desirable to use a plasma treatment that has a high effect of physically etching the polymer surface. Further, it is also preferable to add plasma such as CO ₂ , H ₂ , N ₂ , a mixed gas thereof, and further water vapor. When aiming at processing in a short time, a plasma having a high plasma energy density, a high kinetic energy of ions in the plasma, and a high number density of active species are desirable. From this point of view, microwave plasma treatment, microwave ECR plasma treatment, plasma irradiation with an ion source that easily implants high-energy ions, PBII method, and the like are also desirable.

  The surface activation treatment may be performed only on one side of the polymer film or on both sides. When plasma treatment is performed on one side, the polymer film is placed in contact with the electrode on one side in the plasma treatment with parallel plate electrodes, so that only the side of the polymer film not in contact with the electrode is subjected to plasma treatment. be able to. If a polymer film is placed in a state where it is electrically floated in the space between the two electrodes, plasma treatment can be performed on both sides. Moreover, single-sided processing becomes possible by performing plasma processing in the state which stuck the protective film on the single side | surface of the polymer film. In addition, as a protective film, a PET film with an adhesive or an olefin film can be used.

<Pressurized heat treatment>
The laminate of the present invention is produced by stacking an inorganic substrate provided with a silane coupling agent layer and the polymer film, followed by pressure and heat treatment.

  The pressure heat treatment may be performed while heating a press, a laminate, a roll laminate, or the like, for example, in an atmospheric pressure atmosphere or in a vacuum. A method of heating under pressure in a flexible bag can also be applied. From the viewpoint of improving productivity and reducing the processing cost brought about by high productivity, press or roll lamination in an air atmosphere is preferable, and a method using rolls (roll lamination or the like) is particularly preferable.

  The pressure during the pressure heat treatment is preferably 1 MPa to 20 MPa, more preferably 3 MPa to 10 MPa. If the pressure is too high, the inorganic substrate may be damaged. If the pressure is too low, a non-adhering part may be produced, and adhesion may be insufficient. The temperature during the pressure heat treatment is 150 ° C to 400 ° C, more preferably 250 ° C to 350 ° C. When the polymer film is a polyimide film, if the temperature is too high, the polyimide film may be damaged. If the temperature is too low, the adhesion tends to be weak.

  The pressure heat treatment can be performed in an atmospheric pressure atmosphere as described above, but is preferably performed under vacuum in order to obtain a stable adhesive strength on the entire surface. At this time, the degree of vacuum by a normal oil rotary pump is sufficient, and about 10 Torr or less is sufficient.

  As an apparatus that can be used for pressure heat treatment, for example, “11FD” manufactured by Imoto Seisakusho can be used to perform pressing in a vacuum, and a roll-type film laminator in vacuum or a vacuum is used. For example, “MVLP” manufactured by Meiki Seisakusho Co., Ltd. can be used to perform vacuum laminating such as a film laminator that applies pressure to the entire glass surface at once with a thin rubber film.

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

<Contact angle of each layer surface>
The contact angle with respect to isopropyl alcohol on the surface of the thin film is preferably 0.2 ° to 10 °, more preferably 0.5 ° to 9 °, and still more preferably 0.9 ° to 7.5 °. When the contact angle with respect to isopropyl alcohol on the surface of the thin film exceeds this range, the coating amount of the silane coupling agent becomes unstable and coating spots are likely to occur.

  The difference between the contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate and the contact angle with respect to isopropyl alcohol on the surface of the thin film is 5 degrees or less, preferably 4 degrees or less, more preferably 3 degrees or less, and further preferably 2 degrees. It is as follows.

  When the difference between the contact angle of isopropyl alcohol on the surface of the inorganic substrate and the contact angle of isopropyl alcohol on the surface of the thin film exceeds 5 degrees, the silane coupling agent is applied on the surface of the thin film and the case where the silane coupling agent is applied on the surface of the thin film. The amount of silane coupling agent applied is different from the case where it is applied to the surface, and the thickness of the silane coupling agent layer is the same as the case where the silane coupling agent is applied on the surface of the inorganic substrate. It will be different from the case where it is applied on the surface. In particular, when the contact angle with respect to isopropyl alcohol on the surface of the thin film is larger than the contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate, and the difference exceeds 5 degrees, Coupling agent is applied in the form of dispersed islands, the uniformity of the adhesive force with the polymer film may be impaired, and variation occurs in the application of the silane coupling agent on the thin film surface, Unevenness is likely to occur on the surface of the thin film, which may hinder the application of the polymer film.

  The contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate is preferably 0.3 to 15 degrees, more preferably 1 to 12 degrees, and further preferably 1.5 to 9 degrees. When the contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate exceeds this range, the coating amount of the silane coupling agent becomes unstable and coating spots are likely to occur.

  The contact angle of the thin film surface with respect to water is preferably 2 ° to 30 °, more preferably 3 ° to 25 °, and still more preferably 5 ° to 21 °. When the contact angle with respect to the water of the thin film surface exceeds this range, the coating amount of the silane coupling agent becomes unstable and coating spots are likely to occur.

  The contact angle with respect to methylene chloride on the surface of the thin film is preferably 18 to 45 degrees. When the contact angle with respect to methylene chloride on the surface of the thin film exceeds this range, the coating amount of the silane coupling agent becomes unstable and coating spots are likely to occur.

  In addition, the surface of the inorganic substrate or thin film material when the contact angle is measured is a surface that is not contaminated by organic matter, silicon oil, etc. at a level that can be industrially realized, preferably UV ozone cleaning (in the presence of oxygen). The surface after dry cleaning treatment of irradiating UV with a wavelength of 200 nm or less.

<Adhesive strength>
The surface on which the polymer film is laminated is a region where the polymer film can be easily separated from the inorganic substrate together with the silane coupling agent layer when the cut is made in the polymer film. It consists of an adhesive part. In order to consist of an easy peeling part and a favorable adhesion part, it is preferable to perform the below-mentioned patterning.

  The adhesive strength between the inorganic substrate and the polymer film in the well-bonded portion is 2 times or more, preferably 3 times or more, more preferably 5 times the adhesive strength between the inorganic substrate and the polymer film in the easily peelable portion. That's it. Hereinafter, the magnification with respect to the adhesive strength between the inorganic substrate and the polymer film in the easily peelable portion of the adhesive strength between the inorganic substrate and the polymer film in the good adhesion portion is referred to as an adhesive strength magnification. Moreover, it is preferable that the said adhesive strength magnification is 100 times or less, More preferably, it is 50 times or less. A method for measuring the adhesive strength will be described later.

  When the adhesive strength magnification is less than 2 times, when the polymer film is peeled from the inorganic substrate, the device forming part is peeled off with low stress by utilizing the difference in the adhesive strength between the well-bonded part and the easily peelable part. May become difficult and may reduce the yield of the flexible electronic device. On the other hand, if the adhesive strength magnification is greater than 100 times, the easily peelable portion may peel from the inorganic substrate, or may cause the occurrence of uki or blister (blowing of the coating film) in the easily peelable portion.

  The adhesive strength of the good adhesion part is preferably 0.8 N / cm or more, more preferably 1.5 N / cm or more, still more preferably 2.4 N / cm or more, and most preferably 3.2 N / cm or more. .

  The adhesive strength of the easily peelable portion is preferably less than 1.0 N / cm, more preferably less than 0.67 N / cm, and still more preferably less than 0.34 N / cm. Moreover, it is preferable that the adhesive strength of an easily peelable part is 0.06 N / cm or more, More preferably, it is 0.12 N / cm or more. If the adhesive strength of the easily peelable portion is less than 0.06 N / cm, the easily peelable portion peels from the inorganic substrate due to the influence of the stress generated on the polymer film or the inorganic substrate during the process, It may be a cause of generation of snow, blisters, etc.

<Thin film patterning>
The thin film may be continuously formed on the entire surface of the inorganic substrate, but the thin film is preferably formed in a pattern. In the present invention, a portion where no thin film is formed is a good adhesion portion. That is, the polymer film layer remains on the inorganic substrate through the silane coupling agent layer when the inorganic substrate is recycled. Preferably, the thin film is preferably formed so that the good adhesion portion surrounds the easily peelable portion. Therefore, the thin film is preferably patterned so as to surround the easily peelable portion. As a method for patterning the thin film, a known masking method, or a known method such as an etching method using a resist after a thin film is formed on the front surface, or a lift-off method can be used.

  The pattern shape may be appropriately set according to the type of device to be stacked, and is not particularly limited. The required device shape may be a pattern in which a single device or a plurality of devices are tiled on a plane.

<Patterning of silane coupling agent layer>
In the present invention, the silane coupling agent layer can also be patterned in combination with the patterning by the above-described thin film formation or instead of the patterning by the above-described thin film formation. The patterning treatment of the silane coupling agent layer means that a region where the coating amount of the coupling agent or the activity of the surface activation treatment is intentionally manipulated is created. Thereby, in a laminated body, it has a favorable adhesion part and easy peeling part from which the peeling strength between an inorganic substrate and a polymer film differs, and can form a predetermined pattern. An example of the patterning treatment is a method of manipulating the coating amount of the silane coupling agent using a mask prepared in advance with a predetermined pattern when applying the silane coupling agent. It is also possible to perform patterning by irradiating the surface to which the silane coupling agent is applied with active energy rays and using a technique such as masking or scanning operation at the same time. Here, the active energy ray irradiation means the operation of irradiating energy rays such as ultraviolet rays, electron rays, X-rays, etc., and ozone gas generated near the irradiated surface simultaneously with the ultraviolet ray irradiation light effect as in the ultraviolet ray irradiation treatment of an extremely short wavelength. Include gas exposure effects. In addition to these, patterning can also be performed by corona treatment, vacuum plasma treatment, atmospheric pressure plasma treatment, sandblast treatment, or the like.

<Patterning treatment of polymer film layer>
In the present invention, the polymer film layer can also be patterned in combination with the above-described patterning by thin film formation. The patterning process here refers to creating a region where the activity of the surface activation process is intentionally manipulated.

  An example of the patterning process is a method of manipulating the surface activation process amount using a mask prepared in a predetermined pattern in advance when the surface activation process is performed. Further, when performing the surface activation treatment, it is possible to perform the patterning treatment by using a technique such as masking or scanning operation together. The surface of the polymer film after the surface activation can be further subjected to another active energy ray treatment in combination with masking or scanning to realize the intensity of activity. Here, the active energy ray irradiation means the operation of irradiating energy rays such as ultraviolet rays, electron rays, X-rays, etc., and ozone gas generated near the irradiated surface simultaneously with the ultraviolet ray irradiation light effect as in the ultraviolet ray irradiation treatment of an extremely short wavelength. Include gas exposure effects. In addition to these, patterning can also be performed by corona treatment, vacuum plasma treatment, atmospheric pressure plasma treatment, sandblast treatment, or the like. In addition, it is preferable to make the position of the easy peeling part in a thin film correspond with the position of the easy peeling part in a polymer film layer.

  As described above, the peel strength between the inorganic substrate and the polymer film is different in the laminate by performing the patterning process individually or in combination with each of the thin film, the silane coupling agent, and the polymer film layer. It has an adhesion part and an easy peeling part, and it becomes possible to easily separate the polymer film on which the device is mounted from the inorganic substrate by cutting and peeling the polymer film.

<Method for manufacturing flexible electronic device>
When the laminate of the present invention is used, an electronic device is formed on the polymer film of the laminate using existing equipment and processes for manufacturing electronic devices, and the polymer film is peeled off from the laminate, so that the flexible film is flexible. An electronic device can be fabricated.

  The electronic device in the present invention refers to an electronic circuit including an active element such as a wiring board, a transistor, and a diode that carries electric wiring, and a passive device such as a resistor, a capacitor, and an inductor, and others such as pressure, temperature, light, and humidity. An image display element such as a sensor element, a light emitting element, a liquid crystal display, an electrophoretic display, a self-luminous display, a wireless or wired communication element, an arithmetic element, a memory element, a MEMS element, a solar cell, a thin film transistor, and the like.

  As a method of peeling the polymer film on which the electronic device is mounted from the polymer film laminated substrate, for example, the strong substrate is irradiated with light from the inorganic substrate side to thermally decompose the bonding portion between the inorganic substrate and the polymer film. Or a method of peeling by photolysis, weakening the adhesive strength in advance, a method of peeling the polymer film with a force less than the elastic strength limit value of the polymer film, exposing it to heated water, steam, etc. Examples include a method in which the bond strength at the molecular film interface is weakened and peeled off, but an electronic device is formed at a position corresponding to the easily peelable portion of the polymer film, and then the outer peripheral portion of the easily peelable portion is cut. The method of peeling the area | region in which the electronic device of the molecular film was formed from an inorganic substrate is preferable. This method makes it easier to separate the polymer film and the inorganic substrate.

  In the method for producing a device structure of the present invention, after forming a device on the polymer film of the laminate produced by the above-described method, the polymer film at the easy peelable portion of the laminate is cut to form the device. The polymer film is peeled from the inorganic substrate.

  As a method for cutting the polymer film of the easy peelable part of the laminate, a method of cutting the polymer film with a cutting tool such as a blade or a method of cutting the polymer film by relatively scanning the laser and the laminate. There are a method of cutting, a method of cutting a polymer film by relatively scanning a water jet and a laminate, a method of cutting a polymer film while cutting slightly to a glass layer by a semiconductor chip dicing device, etc. The method is not limited. For example, in adopting the above-described method, it is possible to appropriately employ a technique such as superimposing ultrasonic waves on the cutting tool or adding a reciprocating operation or an up-and-down operation to improve the cutting performance.

  When making an incision in the easily peelable part of the polymer film of the laminate, it is only necessary that the incision position includes at least a part of the easily peelable part, and basically it is basically cut according to the pattern. . However, if an attempt is made to accurately cut according to the pattern at the boundary between the good adhesion portion and the easy peeling portion, an error also occurs. Therefore, it is preferable to cut slightly to the easy peeling portion side from the pattern in terms of increasing productivity. Moreover, in order to prevent peeling without permission before peeling, there may be a production system that cuts into the bonded portion slightly better than the pattern. Furthermore, if the width of the good adhesion portion is set narrow, the polymer film remaining in the good adhesion portion at the time of peeling can be reduced, the use efficiency of the polymer film is improved, and the device for the laminate area The area increases and productivity is improved.

  The method of peeling the polymer film with the device from the inorganic substrate is not particularly limited. However, the method of rolling the film from the end with tweezers, etc., and sticking the adhesive tape to one side of the cut portion of the polymer film, the tape part It is possible to employ a method of winding from a part, a method of winding from one side of a cut portion of the polymer film after vacuum suction, and the like. In addition, when a small curvature occurs in the cut portion of the polymer film during peeling, stress may be applied to the device in that portion and the device may be destroyed. Is desirable. For example, it is desirable to roll while winding on a roll having a large curvature, or to roll using a machine having a configuration in which the roll having a large curvature is located at the peeling portion.

  In addition, a method in which another reinforcing base material is attached in advance to the part to be peeled and the whole reinforcing base material is peeled off is also useful. When the flexible electronic device to be peeled off is the backplane of the display device, it is also possible to obtain a flexible display device by pasting the front plane of the display device in advance and integrating them on the inorganic substrate before peeling them off at the same time. is there.

<Recycling of inorganic substrates>
In the polymer film laminated substrate of the present invention, after peeling the electronic device, the polymer film remaining from the polymer film laminated substrate is completely removed, and the inorganic substrate is reused by performing a simple cleaning process, etc. can do. This is because the adhesive force between the thin film and the silane coupling agent layer in the easy-peeling part is uniform and stable, and the polymer film layer can be smoothly peeled off, leaving almost no peeling residue on the inorganic substrate side. by. This is presumably because the peeling surface when peeling the polymer film becomes the thin film surface (interface between the thin film and the silane coupling agent layer). For this reason, after peeling a polymer film, the state by which the thin film was formed in the inorganic substrate (henceforth an inorganic substrate of this state is called thin film lamination inorganic substrate) is maintained.

  When the polymer film layer is cut and peeled from the inorganic substrate, the polymer film layer remains on the inorganic substrate in a region where peeling is not performed. The polymer film layer remaining on the inorganic substrate needs to be removed by an appropriate formulation such as laser peeling or alkaline chemical treatment.

  In the case where the thin film is formed in a pattern, the silane coupling agent layer is exposed when the polymer film layer is removed at locations where the polymer film layer has not been peeled off. However, due to the above removal, not only the polymer film layer but also the organic part of the silane coupling agent layer is removed in a considerable amount, so that the inorganic component of the silane coupling agent, that is, a component mainly composed of a silicate glass component Only remains on the inorganic substrate. Therefore, in the region of the good adhesion portion (region where the thin film is not formed), even after the removal of the polymer film layer, the surface has a property close to the surface of the inorganic substrate.

  Therefore, in the thin film laminated inorganic substrate, the silane coupling agent layer is formed again in the same manner as when the silane coupling agent layer is first formed, and the polymer film layer is laminated on the silane coupling agent layer. As a thin-film laminated inorganic substrate that is possible and highly recyclable, a silane coupling agent layer is formed on the thin film surface, a polymer film layer is laminated on the silane coupling agent layer, and an electronic device is placed on the polymer film layer. After the formation, an electronic device can be produced by repeating a series of cycles of cutting the polymer film and peeling the polymer film layer from the inorganic substrate.

  When the thin film laminated inorganic substrate is reused, the difference between the contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate and the contact angle with respect to isopropyl alcohol on the surface of the thin film is preferably 5 degrees or less, more preferably 4 degrees or less, More preferably, it is 3 degrees or less, and most preferably 2 degrees or less.

  At the time of reuse of the thin film laminated inorganic substrate, the adhesive strength between the inorganic substrate and the polymer film in the good adhesion portion is preferably at least twice the adhesive strength between the inorganic substrate and the polymer film in the easy peelable portion, More preferably, it is 3 times or more, and further preferably 5 times or more.

  When the thin film laminated inorganic substrate is reused, the adhesive strength of the good adhesion portion is preferably 0.8 N / cm or more, more preferably 1.5 N / cm or more, further preferably 2.4 N / cm or more, most preferably Preferably it is 3.2 N / cm or more.

  When the thin film laminated inorganic substrate is reused, the adhesive strength of the easily peelable portion is preferably less than 1.0 N / cm, more preferably less than 0.67 N / cm, and still more preferably 0.34 N / cm. Is less than. Moreover, it is preferable that the adhesive strength of an easily peelable part is 0.06 N / cm or more, More preferably, it is 0.12 N / cm or more. If the lower limit of the adhesive strength of the easily peelable portion is less than 0.06 N / cm, the easily peelable portion peels off from the inorganic substrate due to the influence of the polymer film or the stress generated on the inorganic substrate side during the process. There may be a case in which uki, blister, etc. occur in the part.

  The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the following examples, and may be appropriately modified and implemented within a range that can meet the purpose described above and below. All of which are within the scope of the present invention.

The physical property evaluation methods in the following examples are as follows.
<Reduced viscosity of polyamic acid solution>
A solution dissolved in N, N-dimethylacetamide so that the polymer concentration was 0.2 g / dl was measured at 30 ° C. using an Ubbelohde type viscosity tube.

<Thickness of polymer film>
The thickness of the polymer film was measured using a micrometer ("Millitron 1245D" manufactured by FineLuf).

<Thickness unevenness of polymer film>
Ten thicknesses of the polymer film were obtained by randomly extracting 10 points from the film to be measured using a micrometer ("Millitron 1245D" manufactured by Finelfu) and measuring the film thickness. From the maximum value (maximum film thickness), the minimum value (minimum film thickness), and the average value (average film thickness), the following values were calculated.
Film thickness variation (%) = 100 × (maximum film thickness−minimum film thickness) ÷ average film thickness

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

<Linear expansion coefficient (CTE) of polymer film>
About the flow direction (MD direction) and the width direction (TD direction) of the polymer film to be measured, the stretch rate is measured under the following conditions, and the intervals of 15 ° C. (30 ° C. to 45 ° C., 45 ° C. to 60 ° C., ...) was measured, and this measurement was performed up to 420 ° C., and an average value of all measured values measured in the MD direction and the TD direction was calculated as a linear expansion coefficient (CTE).
Device name: “TMA4000S” manufactured by MAC Science
Sample length; 20mm
Sample width: 2 mm
Temperature rising start temperature: 30 ° C
Temperature rising end temperature: 420 ° C
Temperature increase rate: 5 ° C./min Atmosphere: Argon initial load: 34.5 g / mm ²

<Glass transition temperature>
Using a DSC differential thermal analyzer, the glass transition temperature of the polymer film was determined from the presence or absence of heat absorption / dissipation due to the structural change in the range from room temperature to 500 ° C. No glass transition temperature was observed in any of the polymer films.

<Evaluation of polymer film: slipperiness>
Two polymer films are stacked on different surfaces (that is, not on the same surface but on the wound outer surface and the wound inner surface when wound as a film roll), and the stacked polymer films are stacked with the thumb and forefinger When sandwiched and rubbed lightly, the case where the polymer film slipped was evaluated as “◯” or “good”, and the case where it did not slip was evaluated as “x” or “bad”. In addition, although it may not slip on winding outer surfaces or between winding inner surfaces, this is not made into an evaluation item.

<Contact angle>
The contact angles of the inorganic substrate surface and the thin film material surface with respect to isopropyl alcohol, water, or methylene iodide were measured after the UV ozone cleaning described later was performed on the inorganic substrate surface and the thin film material surface.

UV ozone cleaning: using a UV / O ₃ cleaning and reforming device (“SKB1102N-01”) and a UV lamp (“SE-1103G05”) manufactured by Run Technical Service Co., Ltd., from a distance of about 3 cm from the UV lamp. Irradiation was performed for 60 seconds. At the time of irradiation, a special gas was not put in the UV / O ₃ cleaning and reforming apparatus, and the irradiation was performed in air, and UV irradiation was performed in an air atmosphere and at room temperature. The UV lamp emits an emission line with a wavelength of 185 nm (short wavelength capable of generating ozone that promotes inactivation treatment) and a wavelength of 254 nm. At this time, the illuminance is about 20 mW / cm ² (illuminance meter (“ORC UV− M03AUV ") at a wavelength of 254 nm.

  Measurement of contact angle: The contact angle was measured according to the JIS R3257 sessile drop method using a contact angle meter CA-X manufactured by Kyowa Interface Science Co., Ltd. Specifically, a film sample of about 50 mm × 50 mm is cut out from the object to be measured, and the sample piece of the obtained measurement object is placed on the surface whose contact angle is to be measured in an environment of a temperature of 23 ° C. and a humidity of 50% RH. The contact angle was measured five times for each solvent of isopropyl alcohol, water, and methylene iodide, and the average value was taken as the contact angle of each solvent with respect to the film sample. The contact angle of isopropyl alcohol with respect to the film sample was measured by setting the dropping amount of isopropyl alcohol to 2.5 μl and reading the contact angle after standing for 10 seconds. The contact angle of water with respect to the film sample was measured by reading the contact angle after standing for 1 minute with the amount of water dropped 1.8 μl. The contact angle of methylene iodide on the film sample was measured by setting the drop amount of methylene iodide to 0.9 μl and reading the contact angle after standing for 30 seconds.

<Thickness of silane coupling agent layer>
For the thickness (nm) of the silane coupling agent layer (SC layer), a sample obtained by applying and drying a silane coupling agent on a separately cleaned Si wafer by the same method as in each example and comparative example was prepared. The film thickness of the silane coupling agent layer formed on the Si wafer was measured by an ellipsometry method using a spectroscopic ellipsometer (“FE-5000” manufactured by Photo) under the following conditions.
Reflection angle range: 45 ° to 80 °
Wavelength range: 250 nm to 800 nm
Wavelength resolution: 1.25 nm
Spot diameter: 1mm
tan Ψ; Measurement accuracy ± 0.01
cosΔ; Measurement accuracy ± 0.01
Measurement: Method Rotating analyzer method Deflector angle: 45 °
Incident angle: 70 ° fixed Analyzer: 0-360 ° in 11.25 ° increments
Wavelength: 250 nm to 800 nm
The film thickness was calculated by fitting by a non-linear least square method. At this time, the model is Air / thin film / Si,
n = C3 / λ4 + C2 / λ2 + C1
k = C6 / λ4 + C5 / λ2 + C4
The wavelength dependence C1 to C6 was determined by the following formula.

<Adhesive strength>
A silane coupling agent was applied to the temporary supporting inorganic substrate by a predetermined method, and then a polymer film was laminated through a predetermined process. And the adhesive strength (180 degree peeling strength) of the inorganic substrate for temporary support and a polymer film was measured on condition of the following according to the 180 degree peeling method of JISC6471. In addition, the sample used for this measurement is provided with an unadhered portion of the polyimide film on one side by designing the size of the polyimide film to 110 mm × 2000 mm with respect to a 100 mm × 1000 mm support (glass). "Grasping."
Device name: “Autograph (registered trademark) AG-IS” manufactured by Shimadzu Corporation
Measurement temperature: Room temperature Peeling speed: 50 mm / min Atmosphere: Atmosphere Measurement sample width: 10 mm

<Appearance>
About quality, it is the result in the visual inspection of the whole laminated body.

<Manufacture of polyimide film>
[Production Example 1]
(Preparation of polyamic acid solution)
After the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, 398 parts by mass of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) and paraphenylenediamine ( (PDA) 147 parts by mass is dissolved in 4600 parts by mass of N, N-dimethylacetamide, and a dispersion obtained by dispersing colloidal silica as a lubricant in dimethylacetamide (“Snowtex (registered trademark)” manufactured by Nissan Chemical Industries, Ltd. ) DMAC-ST30 ”) was added so that the silica (lubricant) was 0.15% by mass with respect to the total amount of polymer solids in the polyamic acid solution, and the mixture was stirred at a reaction temperature of 25 ° C. for 24 hours. A brown and viscous polyamic acid solution V1 having a reduced viscosity as shown in FIG.

(Preparation of polyimide film)
The polyamic acid solution V1 obtained above is applied to the final film thickness (imide) on the smooth surface (non-sliding material surface) of a long polyester film (“A-4100” manufactured by Toyobo Co., Ltd.) having a width of 1050 mm using a slit die. The film thickness after conversion was 25 μm, dried at 105 ° C. for 20 minutes, and then peeled from the polyester film to obtain a self-supporting polyamic acid film having a width of 920 mm.

  Next, the obtained self-supporting polyamic acid film was heated stepwise by a pin tenter in a temperature range of 150 ° C. to 420 ° C. (first stage 180 ° C. × 5 minutes, second stage 270 ° C. × 10 minutes, (Third stage 420 ° C. × 5 minutes) Heat treatment was performed to imidize, and pin grip portions at both ends were dropped with a slit to obtain a long polyimide film F1 (1000 m roll) having a width of 850 mm. Table 1 shows the characteristics of the obtained film F1.

[Production Example 2]
(Preparation of polyamic acid solution)
After the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, 223 parts by mass of 5-amino-2- (p-aminophenyl) benzoxazole (DAMBO), N, N-dimethylacetamide 4416 Next, the colloidal silica dispersion is mixed with 217 parts by mass of pyromellitic dianhydride (PMDA) and the colloidal silica dispersion as a lubricant is polymer solids in the polyamic acid solution. It added so that it might become 0.12 mass% with respect to the total amount, and it stirred for 24 hours at 25 degreeC reaction temperature, and obtained the brown and viscous polyamic-acid solution V2 which has the reduced viscosity shown in Table 1.

(Preparation of polyimide film)
Instead of the polyamic acid solution V1, the polyamic acid solution V2 obtained above was used, and the temperature was raised stepwise in a temperature range of 150 ° C. to 485 ° C. with a pin tenter (first stage 150 ° C. × 5 minutes, 2 minutes Except for the stage 220 ° C. × 5 minutes and the third stage 485 ° C. × 10 minutes), the same operation as in Production Example 1 was performed to obtain a long polyimide film F2 (1000 m roll) having a width of 850 mm. Table 1 shows the characteristics of the obtained film F2.

[Production Example 3]
(Preparation of polyamic acid solution)
The same procedure as in Production Example 2 was carried out except that the colloidal silica dispersion was not added to obtain a polyamic acid solution V3.

(Preparation of polyimide film)
The final thickness (imidized) of the polyamic acid solution V3 obtained above on the smooth surface (non-sliding material surface) of a long polyester film (“A-4100” manufactured by Toyobo Co., Ltd.) having a width of 1050 mm using a comma coater. (After film thickness) is applied to be about 5 μm, and then the polyamic acid solution V2 is applied using a slit die so that the final film thickness is 38 μm including V3, and dried at 105 ° C. for 25 minutes. Then, it was peeled from the polyester film to obtain a self-supporting polyamic acid film having a width of 920 mm.

  Next, the obtained self-supporting polyamic acid film was heated stepwise by a pin tenter in a temperature range of 180 ° C. to 495 ° C. (first stage 180 ° C. × 5 minutes, second stage 220 ° C. × 5 minutes, The third stage (495 ° C. × 10 minutes) was subjected to heat treatment to imidize, and pin holding portions at both ends were dropped with slits to obtain a long polyimide film F3 (1000 m roll) having a width of 850 mm. The properties of the obtained film F3 are shown in Table 1.

<Manufacture of plasma-treated film>
One side of the polyimide film F1 obtained in Production Example 1 was subjected to vacuum plasma treatment to obtain a plasma-treated polyimide film P1. Table 2 shows the characteristics of the obtained plasma-treated polyimide film P1.

  As the vacuum plasma processing, RIE mode using parallel plate type electrodes and RF plasma processing are adopted, nitrogen gas is introduced into the vacuum chamber, high frequency power of 13.54 MHz is introduced, and the processing time is 3 minutes.

  Moreover, in plasma processing polyimide film P1, it replaced with polyimide film F1, and except having used polyimide film F2, it carried out similarly to plasma processing polyimide film P1, and obtained plasma processing polyimide film P2.

  Further, in the plasma-treated polyimide film P1, a plasma-treated polyimide film was used except that the polyimide film F3 was used instead of the polyimide film F1 and that the same plasma treatment was performed on one side of the polyimide film F3 that does not contain a lubricant. A plasma-treated polyimide film P3 was obtained in the same manner as P1.

  Further, in the plasma-treated polyimide film P1, a plasma-treated PET was used in the same manner as the plasma-treated polyimide film P1 except that a polyethylene terephthalate (PET) film A4100 (manufactured by Toyobo Co., Ltd.) having a thickness of 100 μm was used instead of the polyimide film F1. Film P4 was obtained.

Further, in the plasma-treated polyimide film P1, instead of the polyimide film F1, a 100 μm-thick polyethylene naphthalate (PEN) film “Teonex (registered trademark)” (manufactured by Teijin Limited) was used. Similarly, a plasma-treated PEN film P5 was obtained.
Table 2 shows the characteristics of the obtained plasma-treated films P1 to P5.

<Thin film formation on inorganic substrates>
A soda glass plate of 370 mm × 470 mm × 1.1 mmt was subjected to ultrasonic cleaning using ultrapure water and sufficiently dried with dry air through a HEPA filter. Thereafter, the substrate is placed in a vacuum chamber for thin film processing, and is formed by a DC sputtering method at a substrate temperature of 100 ° C. at a substrate temperature of 100 ° C. through a pattern of stainless steel masks in which a plurality of 50 mm × 80 mm openings are connected. A 49 nm gold thin film was formed into a pattern in which a square shape was connected to obtain a thin film laminated inorganic substrate G1.

  Corning glass (EAGLE XG (registered trademark)) of 370 mm × 470 mm × 0.7 mmt was subjected to ultrasonic cleaning with ultrapure water and sufficiently dried with dry air through a HEPA filter. Then, it is put into a vacuum chamber for thin film processing, and is heated by a DC sputtering method through a stainless steel mask having a pattern in which a plurality of 50 mm × 80 mm openings are connected, and a thickness of 48 nm. A Cr thin film was formed into a pattern in which a square shape was connected to obtain a thin film laminated inorganic substrate G2.

  Corning glass (EAGLE XG (registered trademark)) of 370 mm × 470 mm × 0.7 mmt was subjected to ultrasonic cleaning using ultrapure water and sufficiently dried with dry air through a HEPA filter. Then, it is put into a vacuum chamber for thin film processing, and is heated by a DC sputtering method through a stainless steel mask having a pattern in which a plurality of 50 mm × 80 mm openings are connected to each other, and is heated to a thickness of 50 nm. A silicon carbide thin film was formed into a pattern in which a square shape was connected to obtain a thin film laminated inorganic substrate G3.

  In the thin film laminated inorganic substrate G2, a silicon nitride thin film having a thickness of 98 nm at a substrate temperature of 210 ° C. is obtained by a DC reactive sputtering method instead of forming a 48 nm thick Cr thin film by DC sputtering without heating. A thin-film laminated inorganic substrate G4 was obtained in the same manner as the thin-film laminated inorganic substrate G2, except that was formed.

  In the thin film laminated inorganic substrate G2, a thin film laminated inorganic substrate G5 was obtained in the same manner as the thin film laminated inorganic substrate G2, except that a 46 nm thick titanium thin film was formed instead of the 48 nm thick Cr thin film.

  The thin film laminated inorganic substrate G2 is the same as the thin film laminated inorganic substrate G2 except that a silicon thin film with a thickness of 150 nm is formed by RF sputtering instead of forming a Cr thin film with a thickness of 48 nm by DC sputtering. Thus, a thin film laminated inorganic substrate G6 was obtained.

  In the thin film laminated inorganic substrate G2, the thin film laminated inorganic substrate G2 except that a silicon carbide thin film having a thickness of 55 nm was formed without using a mask instead of forming a Cr thin film having a thickness of 48 nm through a mask. In the same manner, a thin film laminated inorganic substrate G7 was obtained.

  In the thin film laminated inorganic substrate G2, instead of forming a 48 nm thick Cr thin film by a DC sputtering method through a mask, a fluorine water repellent film having a thickness of 15 nm by an EB vapor deposition method without using a mask. A thin film laminated inorganic substrate G8 was obtained in the same manner as the thin film laminated inorganic substrate G2, except that a film was formed.

Corning glass (EAGLE XG (registered trademark)) of 370 mm × 470 mm × 0.7 mmt was ultrasonically washed with ultrapure water and sufficiently dried with dry air through a HEPA filter to obtain an inorganic substrate G9.
The conditions for forming the thin film are shown in Table 3.

<Silane coupling agent layer formation on inorganic substrate>
<Application example 1 (spin coating method)>
A silane coupling agent diluted solution was prepared by diluting 3-aminopropyltrimethoxysilane (“KBM-903” manufactured by Shin-Etsu Chemical Co., Ltd.) to 0.5 mass% with isopropyl alcohol as a silane coupling agent. The thin film laminated inorganic substrate G1 was placed on a spin coater manufactured by Japan Create Co., and 70 ml of isopropyl alcohol was dropped onto the center of the rotation, and the liquid was shaken off and dried at 500 rpm. 35 ml was dropped on the center of rotation, first rotated at 500 rpm for 10 seconds, then increased to 1500 rpm and rotated for 20 seconds, and the silane coupling agent diluted solution was shaken off. Next, the thin-film laminated inorganic substrate G1 coated with the silane coupling agent is placed on a hot plate heated to 100 ° C. placed in a clean bench so that the silane coupling agent coating surface is on top, By heating for about 3 minutes, a silane coupling agent-coated substrate S1 was obtained.

  In the silane coupling agent coated substrate S1, the silane coupling agent coated substrates S2 to S8 and S10 are the same as the silane coupling agent coated substrate S1, except that the thin film laminated inorganic substrate G1 is changed to the thin film laminated inorganic substrates G2 to G8. Obtained.

In the silane coupling agent coated substrate S1, the thin film laminated inorganic substrate G1 is changed to the thin film laminated inorganic substrate G9, and the silane coupling agent layer is patterned, so that the silane cup is similar to the silane coupling agent coated substrate S1. A ring agent-coated substrate S9 was obtained. The silane coupling agent layer is patterned by shielding a necessary portion with a stainless steel mask and using a UV / O ₃ cleaning reformer ("SKB1102N-01") manufactured by Run Technical Service Co., Ltd. used in UV ozone cleaning. ) And a UV lamp (“SE-1103G05”), irradiation was performed for 240 seconds from a distance of about 3 cm from the UV lamp.

<Application example 2 (vapor phase coating method)>
Using a vacuum chamber having a hot plate, a silane coupling agent was applied to the inorganic substrate under the following conditions.

100 parts by mass of a silane coupling agent (“KBM-903” manufactured by Shin-Etsu Chemical Co., Ltd .: 3-aminopropyltrimethoxysilane) was filled in a petri dish and allowed to stand on a hot plate. At this time, the hot plate temperature is 25 ° C. Next, the thin film laminated inorganic substrate G2 is held horizontally with the thin film surface facing downward at a position 300 mm away from the liquid surface of the silane coupling agent, the vacuum chamber is closed, and the oxygen concentration is 0.1 at atmospheric pressure. Nitrogen gas was introduced until the volume was less than or equal to volume%. Next, the introduction of nitrogen gas was stopped, the inside of the chamber was depressurized to 3 × 10 ⁻⁴ Pa, the hot plate temperature was raised to 120 ° C., held for 10 minutes, and exposed to the silane coupling agent vapor. Then, the hot plate temperature is lowered, and at the same time, clean nitrogen gas is gently introduced into the vacuum chamber to return to atmospheric pressure, the glass plate is taken out, and a silane coupling agent is applied to the hot plate at 100 ° C. in a clean environment. The substrate was placed face up and heat treated for about 3 minutes to obtain a silane coupling agent coated substrate V2 shown in Table 4.

  The silane coupling agent coated substrates V3 and V4 are obtained in the same manner as the silane coupling agent coated substrate V2, except that the thin film laminated inorganic substrate G2 used in the silane coupling agent coated substrate V2 is changed to the thin film laminated inorganic substrates G3 and G4. It was.

<Example 1>
<Production of laminate and evaluation of initial characteristics>
The plasma treatment surface of the plasma treatment film P1 trimmed into a 360 mm × 460 mm rectangle is exposed on the silane coupling agent layer side of the obtained silane coupling agent application substrate S1, and the silane coupling agent application substrate is exposed to a width of 5 mm around the periphery. Thus, the plasma-treated film P1 was temporarily laminated on each silane coupling agent layer of the obtained silane coupling agent-treated support using a laminator (SE650nH manufactured by Climb Products). did. Lamination conditions were an inorganic substrate side temperature of 100 ° C., a roll pressure of 5 kg / cm ² during lamination, and a roll speed of 5 mm / second. The polyimide film after temporary lamination did not peel off due to its own weight, but had such adhesiveness that it was easily peeled off when the film edge was scratched. Thereafter, the obtained temporary laminated laminated substrate was put in a clean oven, heated at 200 ° C. for 30 minutes, and then allowed to cool to room temperature, to obtain a polymer film laminated substrate. Table 5 shows the characteristics of the obtained multilayer substrate.

  As for the adhesive strength between the polymer film and the inorganic substrate in the laminate, for the sample in which the thin film was formed in a pattern, the adhesive strength at the thin film forming portion was the adhesive strength at the easy peeling portion, and the thin film was formed. The adhesive strength of the non-existing portion was defined as the adhesive strength of the good bonded portion. In addition, in the case of a sample that has been subjected to inactivation treatment using active energy rays, etc., the adhesive strength of the inactivated part is set to be the adhesion of the easily peelable part, and the adhesive strength of the non-inactivated part is well bonded. It was set as the adhesive strength of the part.

<Evaluation of recycling characteristics>
The laminated substrate manufactured in the same process as the laminated substrate for which the adhesive strength was measured was subjected to an operation corresponding to recycling, and the characteristics when the inorganic substrate was reused were evaluated. Specifically, after cutting off from the inorganic substrate by making a cut around the easy-peeling portion, the substrate with a part of the polymer film layer was immersed in a 10% aqueous sodium hydroxide solution at room temperature for 20 hours, Brushing, then washing with water, cleaning and cleaning with a glass cleaning device for liquid crystal substrates, drying and UV ozone cleaning for 3 minutes in a dry environment, and then forming and laminating a silane coupling agent layer on an inorganic substrate The body was prepared in the same manner as before recycling, and the appearance quality was observed, and the adhesive strength at the easily peeled portion and the good bonded portion was evaluated. Table 5 shows the recycling characteristics.

<Examples 2 to 7>
The polymer film laminated substrates of Examples 2 to 7 were the same as Example 1 except that the silane coupling agent-coated substrate used in Example 1 was changed to S2, S3, S4, S7, S10, and V2. Got. The evaluation results of the recycling characteristics were the same as in Example 1.
Table 5 shows the evaluation results of the obtained multilayer substrate and the evaluation results of the recycling characteristics.

<Comparative Examples 1-3>
Except having changed the silane coupling agent application board | substrate used in Example 1 into S5, S6, and S8, it carried out similarly to Example 1, and obtained the polymer film laminated substrate of Comparative Examples 1-3. The evaluation results of the recycling characteristics were the same as in Example 1.
Table 5 shows the evaluation results of the obtained multilayer substrate and the evaluation results of the recycling characteristics.

<Comparative example 4>
Polymer film lamination of Comparative Example 4 in the same manner as in Example 1 except that the silane coupling agent-coated substrate used in Example 1 was changed to a silane coupling agent-coated substrate S9 in which no thin film was formed. A substrate was obtained. The evaluation results of the recycling characteristics were the same as in Example 1.

  Table 5 shows the evaluation results of the obtained multilayer substrate and the evaluation results of the recycling characteristics. In addition, the protrusion which seems to be because the foreign material entered between the polymer film and the inorganic substrate in the easy peeling part at the time of recycling was scattered.

<Examples 8 to 15>
The silane coupling agent-coated substrate and the plasma-treated film were appropriately changed according to the combinations shown in Table 6, and the same operations as in Example 1 were performed and evaluated in the same manner. The results are shown in Table 6. In the case of using the plasma-treated film P4 or P5, the heat treatment temperature in the clean oven after lamination was set to 150 ° C. The evaluation results of the recycling characteristics were the same as in Example 1.

  Table 6 shows the evaluation results of the obtained multilayer substrate and the evaluation results of the recycling characteristics.

<Application example 1>
A thin film transistor having a bottom gate structure on a polymer film by using the laminate obtained in Example 1, Example 2, Example 3, Example 13, Example 15, and Comparative Example 2 and performing the following steps. An array was made.

  A 100 nm gas barrier film made of SiON was formed on the entire surface of the polymer film using a reactive sputtering method. Next, an aluminum layer having a thickness of 80 nm was formed by a sputtering method, and a gate wiring and a gate electrode were formed by a photolithography method. Subsequently, an epoxy resin-based gate insulating film (thickness 80 nm) was formed using a slit die coater. Further, a 5 nm Cr layer and a 40 nm gold layer were formed by sputtering, and a source electrode and a drain electrode were formed by photolithography. In addition, using a slit die coater, an epoxy resin that becomes an insulating layer / dam layer is applied, and a 250-nm thick dam layer for a semiconductor layer including a source electrode and a drain electrode is formed by ablation with a UV-YAG laser. A circular shape having a diameter of 100 μm was formed, and a via forming a connection point with the upper electrode was simultaneously formed. Then, polythiophene, which is an organic semiconductor, was coated in the dam by an ink jet printing method, a silver paste was buried in the via portion, and an aluminum wiring was formed as an upper electrode to form a thin film transistor array having 640 × 480 pixels.

  The obtained thin film transistor array was used as a back plane, and an electrophoretic display medium was overlaid on the front plane to form a display element. The yield and display performance of the transistor were determined by ON / OFF of each pixel. As a result, the thin film transistor array produced using any of the laminates had good display performance.

  In addition, after the front plane is overlaid on the thin film transistor array, the polymer film portion is burned out with a UV-YAG laser along the inner side of the thin film pattern about 0.5 mm, and a thin razor blade is used from the edge of the cut. Peeling was performed to scoop up.

  The thin film transistor array produced using the laminates obtained in Example 1, Example 2, Example 3, Example 13, and Example 15 can be easily peeled off, and a flexible electrophoretic display device can be used. I was able to get it.

  On the other hand, the thin film transistor array produced using the laminate obtained in Comparative Example 2 required a larger force than the above Examples to perform the above-described peeling. In addition, although the display of the electrophoretic portion before peeling was good, after the peeling, some scanning lines had malfunctioned, and an area that could not be rewritten was generated.

<Application example 2>
After peeling the flexible electrophoretic display device in Application Example 1, the inorganic substrate was immersed in a 10% aqueous sodium hydroxide solution at room temperature for 20 hours. Thereafter, it was washed with water, further cleaned with a glass cleaning device for liquid crystal substrates, and after drying, UV ozone cleaning was performed for 3 minutes. Thereafter, the process returns to the above-described <Formation of Silane Coupling Agent Layer on Inorganic Substrate>, and the subsequent steps were performed by the same production method as that for producing the laminate first to obtain a laminate. The quality of the obtained laminate was good, and it was sufficiently recyclable.

<Application example 3>
The laminates obtained in Examples 4 to 9, Example 12 and Example 14 were covered with a stainless steel frame having an opening and fixed to a substrate holder in the sputtering apparatus. The substrate holder and the support of the laminate were fixed in close contact with each other, and a coolant was allowed to flow through the substrate holder so that the temperature of the laminate could be set. The temperature of the laminate was set to 2 ° C. First, plasma treatment was applied to the polymer film surface of the laminate. The plasma treatment conditions were as follows: argon gas, frequency 13.56 MHz, output 200 W, gas pressure 1 × 10 ⁻³ Torr, treatment temperature 2 ° C., treatment time 2 minutes. Next, under the conditions of a frequency of 13.56 MHz, an output of 450 W, and a gas pressure of 3 × 10 ⁻³ Torr, a nickel-chromium (Cr 10% by mass) alloy target is used to perform a DC magnetron sputtering method in an argon atmosphere at 1 nm / A nickel-chromium alloy coating (underlayer) having a thickness of 11 nm was formed at a rate of seconds. Subsequently, the temperature of the laminated body was set to 2 ° C., and sputtering was performed. Then, copper was vapor-deposited at a rate of 10 nm / second to form a copper thin film having a thickness of 0.22 μm. Thus, the laminated board with a base metal thin film formation film was obtained from each laminated body. The thicknesses of the copper and NiCr layers were confirmed by the fluorescent X-ray method.

Next, a laminated board with a base metal thin film forming film from each film is fixed to a Cu frame, and an electroplating solution (copper sulfate 80 g / l, sulfuric acid 210 g / l, HCl, gloss, using a copper sulfate plating bath). A thick copper plating layer (thickening layer) having a thickness of 4 μm was formed by immersing in a small amount of the agent and passing 1.5 A / dm ^{2 of} electricity. Then, it heat-processed for 10 minutes at 120 degreeC, it dried, and the copper foil layer was formed in the polymer film surface of a laminated body.

After applying and drying a photoresist (“FR-200” manufactured by Shipley Co., Ltd.) on each of the obtained copper foil layers, it was subjected to off-contact exposure with a glass photomask and further developed with a 1.2 mass% KOH aqueous solution. . Next, etching was performed with a cupric chloride etching line containing HCl and hydrogen peroxide at 40 ° C. and a spray pressure of ² kgf / cm ² to form a line row of lines / spaces = 20 μm / 20 μm as a test pattern. Next, after electroless tin plating was performed to a thickness of 0.5 μm, annealing treatment was performed at 125 ° C. for 1 hour to obtain a wiring pattern.

  The obtained wiring pattern was observed with an optical microscope, and the presence or absence of disconnection / short circuit was checked using the test pattern. As a result, there was no disconnection or short circuit in the wiring pattern, and the pattern shape was good. Subsequently, the polymer film was peeled from the glass plate by the same method as in Application Example 1 to obtain a flexible wiring board. The flexibility of the obtained flexible wiring board was good.

  The polymer film laminated substrate of the present invention can easily peel the polymer film on which the electronic device is mounted from the inorganic substrate after forming the electronic device on the polymer film. In addition, even when the inorganic substrate that has been peeled off is recycled, the polymer film on which the electronic device is placed can be easily peeled off from the inorganic substrate in the same manner as before recycling. It is useful for manufacturing and contributes greatly to the industry.

Claims (8)

A thin film is formed continuously or discontinuously on a part of at least one surface of the inorganic substrate, a silane coupling agent layer is formed continuously or discontinuously on the thin film, and a polymer film layer is further formed on the silane coupling agent layer. Is a polymer film laminated substrate laminated,
The difference between the contact angle with respect to isopropyl alcohol on the surface of the inorganic substrate and the contact angle with respect to isopropyl alcohol on the surface of the thin film is 5 degrees or less,
The surface on which the polymer film is laminated is a region where the polymer film can be easily separated from the inorganic substrate together with the silane coupling agent layer when the cut is made in the polymer film. It consists of an adhesive part,
The polymer film laminated substrate characterized in that the adhesive strength between the inorganic substrate and the polymer film in the good adhesion portion is at least twice the adhesive strength between the inorganic substrate and the polymer film in the easily peelable portion.   The polymer film laminated substrate according to claim 1, wherein the thin film contains at least one of Cr, a noble metal, a metal carbide, or a metal nitride.   The thin film is formed discontinuously on at least one surface of the inorganic substrate, the easy peeling part is covered with the thin film, and the good adhesion part is not covered with the thin film. Polymer film laminated substrate.   The polymer film laminated substrate according to claim 1, wherein the polymer film is a polyimide film.   The polymer film laminated substrate according to any one of claims 1 to 3, which is used for temporarily supporting a polymer film material on an inorganic substrate when an electronic device is formed on the polymer film. Forming a thin film continuously or discontinuously on a part of at least one side of the inorganic substrate;
Forming a silane coupling agent layer continuously or discontinuously on the thin film;
Laminating a plurality of polymer film layers on the silane coupling agent layer;
Adhering adjacent layers by heating and pressing; and
Forming an electronic device on the polymer film;
Cutting the polymer film layer and peeling at least part of the polymer film layer from the inorganic substrate together with the electronic device and the silane coupling agent layer;
A method of manufacturing a flexible electronic device, comprising: In the above step of laminating the polymer film layer,
The flexible film according to claim 6, wherein a polymer solution or a polymer precursor solution is applied onto a silane coupling agent layer or a polymer film layer, and the applied solution is dried and heated to laminate the polymer film layer. Electronic device manufacturing method.   The manufacturing method of the flexible electronic device of Claim 6 or 7 including the process of forming a predetermined pattern in a thin film.