laminated body

Abstract

The objective of this invention is to provide a laminate that exhibits excellent long-term heat resistance even when using an inorganic substrate with a large surface roughness. The solution is a laminate characterized by sequentially comprising an inorganic substrate, a silane coupling agent layer, and a heat-resistant polymer film, and satisfying the following (A) to (C): (A) The peel strength F0 of the laminate using a 90° peel method is 1.0 N / cm or more and 20 N / cm or less; (B) On the surface of the inorganic substrate after the heat-resistant polymer film has been peeled off at a 90° angle from the laminate, the area of ​​the peeled portion at the interface between the inorganic substrate and the silane coupling agent layer is 20% or less of the total peeled surface; (C) The peel strength F1 of the laminate using a 90° peel method after heating at 350°C for 500 hours under nitrogen atmosphere is greater than the aforementioned F0.

Description

[Technical Field]

[0001] This invention relates to laminates. More specifically, it relates to laminates having a heat-resistant polymer film, an adhesive layer, and an inorganic substrate sequentially laminated. [Previous Technology]

[0002] In recent years, there has been a great deal of research and development on forming such components on polymer films, with the aim of making functional components such as semiconductor components, MEMS components, and display components lighter, smaller / thinner, and more flexible. That is, ceramics, which are known to be used as substrates for so-called electronic components such as information communication devices (playback machines, mobile wireless devices, mobile communication devices, etc.), radar, and high-speed information processing devices, are known to have heat resistance and can cope with the high frequency (reaching the GHz band) of the signal band of information communication devices. However, because ceramics are not flexible and are difficult to make thin, they have the disadvantage of limiting the fields of application. Recently, polymer films have been used as substrates.

[0003] As a method for manufacturing a multilayer body in which functional elements are formed on the aforementioned polymer film, the following methods are known: (1) a method of depositing a metal layer on a resin film with an adhesive or binder as a barrier (Patent Documents 1-3); (2) a method of depositing a metal layer by heating and pressurizing after mounting the metal layer on the resin film (Patent Document 4); (3) a method of applying a resin film forming varnish to a polymer film or a metal layer, and then depositing it with the metal layer or polymer film after drying; (4) a method of distributing resin powder for resin film forming on a metal layer and compressing it; (5) a method of forming a conductive material on a resin film by screen printing and sputtering (Patent Document 5), etc. Furthermore, when manufacturing a multilayer multilayer body with three or more layers, the aforementioned methods can be combined in various ways.

[0004] On the other hand, in the process of forming the aforementioned laminated body, the aforementioned laminated system is mostly exposed to high temperatures. For example, in the fabrication of low-temperature polycrystalline silicon thin-film transistors, heating to around 450°C is required for dehydrogenation, and in the fabrication of hydrogenated amorphous silicon thin films, temperatures of around 200-300°C are applied to the film. Therefore, the polymer film constituting the laminated body is required to have heat resistance. As a practical problem, the number of polymer films that can withstand practical high temperatures is limited. Furthermore, in the bonding system of polymer film to metal layer as described above, it can be considered that adhesives and bonding agents can be used. Heat resistance is also required for the bonding surface between the polymer film and the metal layer (i.e., the adhesive and bonding agent used for bonding). However, commonly used adhesives and bonding agents do not have sufficient heat resistance, leading to problems such as peeling of the polymer film (i.e., reduced peel strength), blister formation, and carbonization during the manufacturing process or actual use, rendering them unusable. Especially when exposed to high temperatures for extended periods or used at high temperatures, the peel strength may decrease to the point where the product cannot be used.

[0005] In view of this situation, as a laminate of polymer thin film and metal layer, there has been a proposal to laminate a polyimide film with excellent heat resistance, toughness, and thin-film-forming properties, and a polyphenylene ether layer, to an inorganic layer containing a metal, using a silane coupling agent (Patent Documents 6-9). [Prior Art Documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-136600 [Patent Document 2] Japanese Patent Application Publication No. 2007-101496 [Patent Document 3] Japanese Patent Application Publication No. 2007-101497 [Patent Document 4] Japanese Patent Application Publication No. 2009-117192 [Patent Document 5] Japanese Patent Application Publication No. Hei 11-121148 [Patent Document 6] Japanese Patent Application Publication No. 2019-119126 [Patent Document 7] Japanese Patent Application Publication No. 2020-59169 [Patent Document 8] Japanese Patent No. 6721041 [Patent Document 9] Japanese Patent Application Publication No. 2015-13474 [Summary of the Invention]

[0007] [The problem the invention aims to solve]

[0008] However, it is known that because the silane coupling agent coating layer obtained by the method disclosed in Patent Documents 6-8 is extremely thin, no practically usable adhesion force (peel strength) is exhibited in metal layers with an arithmetic surface roughness (Ra) greater than 0.05 μm. The applicable metal layers are limited to those with small surface roughness. In particular, when polyimide films and metal layers are laminated using a silane coupling agent, it is known that under general heating and pressing conditions, since the polymer does not soften and flow into the surface of the metal layer, an anchoring effect near the surface of the metal layer cannot be expected, and no adhesion force is exhibited.

[0009] Furthermore, regarding the method disclosed in Patent Document 9, although polyphenylene ether can be used as a heat-resistant polymer resin layer, its heat resistance (solder heat resistance: 260-280°C, long-term heat resistance) is poor, and it is not a practical material.

[0010] This invention was made in view of the above-mentioned problems, and its objective is to provide a laminate that exhibits excellent long-term heat resistance even when using inorganic substrates with high surface roughness. [Means for solving the problems]

[0011] Hereinafter, the present invention comprises the following components. [1] A laminate, characterized in that it sequentially comprises an inorganic substrate, a silane coupling agent layer, and a heat-resistant polymer film, and satisfies the following (A) to (C): (A) The peel strength F0 when the heat-resistant polymer film is peeled off from the aforementioned inorganic substrate at 90° is 1.0 N / cm or more and 20 N / cm or less; (B) On the surface of the inorganic substrate after the heat-resistant polymer film is peeled off from the aforementioned inorganic substrate at 90°, the area of ​​the peeled portion at the interface between the aforementioned inorganic substrate and the aforementioned silane coupling agent layer is 20% or less of the entire peeled surface; (C) After the laminate is heated at 350° for 500 hours in a nitrogen atmosphere, the peel strength F1 when the heat-resistant polymer film is peeled off from the aforementioned inorganic substrate at 90° is greater than the aforementioned F0. [2] A laminate as described in [1], wherein the thickness of the silane coupling agent layer of the laminate is more than 0.01 times the surface roughness (PV value) of the inorganic substrate. [3] A laminate as described in [1] or [2], characterized in that the inorganic substrate contains 3d metal elements. [4] A laminate as described in any one of [1] to [3], characterized in that the inorganic substrate is one or more selected from the group consisting of SUS, copper, brass, iron and nickel. [5] A laminate as described in any one of [1] to [4], characterized in that the heat-resistant polymer film is a polyimide film. [6] A probe card, wherein the constituent components include a laminate as described in any one of [1] to [5]. [7] A flat cable, wherein the constituent components include a laminate as described in any one of [1] to [5]. [8] A heating element comprising a laminate as described in any one of [1] to [5] in its constituent components. [9] An electrical electronic substrate comprising a laminate as described in any one of [1] to [5] in its constituent components.

[10] A solar cell comprising a laminate as described in any one of [1] to [5] in its constituent components.

[11] A method for manufacturing a laminate comprising the following steps in sequence: (1) coating a silane coupling agent layer on at least one side of an inorganic substrate; (2) overlapping the silane coupling agent coated surface of the inorganic substrate with the heat-resistant polymer film; (3) pressing the inorganic substrate and the heat-resistant polymer film together; The method for manufacturing the laminate is characterized in that: by using the same coating method as in step (1), the silane coupling agent is coated onto a KBr plate to form a coated plate, and the area of ​​the peaks originating from functional groups in the spectrum obtained by measuring the coated plate by micro-infrared spectroscopy is 15 or less. [Effects of the Invention]

[0012] According to the present invention, a laminate with excellent long-term heat resistance and high quality can be provided even when using an inorganic substrate with large surface roughness.

Implementation Method

[0014] [Form for implementing the invention]

[0015] <Heat-resistant polymer film> Examples of the heat-resistant polymer film (hereinafter also referred to as polymer film) of the present invention include: aromatic polyimides such as polyimide, polyamide-imide, polyether-imide, and fluorinated polyimide, or polyimide-based resins such as alicyclic polyimide, polyurethane, polyetherurethane, polyetherketone, cellulose acetate, cellulose nitrate, aromatic polyamide, and polyphenylene sulfide. However, since the aforementioned polymer films are used in conjunction with heat treatment processes at 350°C or higher and heating to 350°C or higher, the practical applicability of the illustrated polymer films is limited. Among the aforementioned polymer films, those using so-called super engineering plastics are preferred. More specifically, they can be listed as: aromatic polyimide films, aromatic amide films, aromatic amide-amide-imide films, aromatic benzo[a]azole films, aromatic benzo[a]thiazole films, aromatic benzo[a]imidazole films, etc.

[0016] From the viewpoint of ideally mounting functional components, it is preferable that the tensile modulus of elasticity of the aforementioned polymer film at 25°C is 2 GPa or higher, more preferably 4 GPa or higher, and even more preferably 7 GPa or higher. Furthermore, from the viewpoint of flexibility, the tensile modulus of elasticity of the aforementioned polymer film at 25°C can be set to, for example, 15 GPa or lower, 10 GPa or lower, etc.

[0017] Hereinafter, a polyimide resin film (also referred to as a polyimide film) as an example of the aforementioned polymer film will be described in detail. Generally, a polyimide resin film is obtained by: coating a polyamide acid (polyimide precursor) solution obtained by reacting a diamine with a tetracarboxylic acid in a solvent onto a support for making a polyimide film and drying it to form a green film (hereinafter also referred to as a "polyamide acid film"); and further subjecting the green film to high-temperature heat treatment on the support for making a polyimide film, or in a state of being peeled off from the support, to a dehydration and ring-closing reaction.

[0018] The coating of polyamide (polyimide precursor) solution can be carried out by, for example, spin coating, doctor blade coating, applicator, corner wheel coating machine, screen printing, slot coating, reverse coating, dip coating, curtain coating, slit coating and other conventional solution coating methods.

[0019] As a diamine constituting polyamide, there are no particular limitations, and the following can be used: aromatic diamines, aliphatic diamines, and alicyclic diamines commonly used in the synthesis of polyimides. From the viewpoint of heat resistance, aromatic diamines are preferred, and among aromatic diamines, those with a benzo[a]azole structure are even better. If an aromatic diamine with a benzo[a]azole structure is used, it becomes possible to exhibit high heat resistance while also exhibiting a high modulus of elasticity, low thermal shrinkage, and low coefficient of linear expansion. Diamines can be used alone or in combination of two or more.

[0020] As an aromatic diamine having a benzo[a]azole structure, there is no particular limitation, for example: 5-amino-2-(p-aminophenyl)benzo[a]azole, 6-amino-2-(p-aminophenyl)benzo[a]azole, 5-amino-2-(m-aminophenyl)benzo[a]azole, 6-amino-2-(m-aminophenyl)benzo[a]azole, 2,2'-p-phenylbis(5-aminobenzo[a]azole), 2,2'-p-phenylbis(6-aminobenzo[a]azole), 1-(5-aminobenzo[a]azole)-4-(6-aminobenzo[a]azole)benzene, 2,6-(4,4'-diaminodiphenyl)benzo[a]azole [1,2-d:5,4-d']bis(2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bis(2,6-(3,4'-diaminodiphenyl)benzo[1,2-d:5,4-d']bis(2,6-(3,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bis(2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:5,4-d']bis(2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:4,5 ...

[0021] Examples of aromatic diamines other than those having a benzo[a]azole structure 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'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)phenyl]one, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-(3-aminophenoxy)phenyl] ketone, bis[4-(3-aminophenoxy)phenyl] sulfide, bis[4-(3-aminophenoxy)phenyl] ketone, 2,2-bis[4-(3-aminophenoxy)phenyl] ketone, etc. Propane, 2,2-bis[4-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3, 3'-Diaminodiphenyl sulfene, 3,4'-Diaminodiphenyl sulfene, 4,4'-Diaminodiphenyl sulfene, 3,3'-Diaminodiphenyl sulfene, 3,4'-Diaminodiphenyl sulfene, 4,4'-Diaminodiphenyl sulfene, 3,3'-Diaminodiphenyl ketone, 3,4'-Diaminodiphenyl ketone, 4,4'-Diaminodiphenyl ketone, 3,3'-di... Aminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis[4-(4-aminophenoxy)phenyl]methane, 1,1-bis[4-(4-aminophenoxy)phenyl]ethane, 1,2-bis[4-(4-aminophenoxy)phenyl]ethane, 1,1-bis[4-(4-aminophenoxy)phenyl]propane, 1,2-bis[4-(4-aminophenoxy)phenyl]propane, 1,3-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 1,1-bis[4-(4-aminophenoxy)phenyl]butane, 1,3-bis[4-(4-aminophenoxy)phenyl]butane, 1,4-bis[4-( [4-aminophenoxy)phenyl]butane, 2,2-bis[4-(4-aminophenoxy)phenyl]butane, 2,3-bis[4-(4-aminophenoxy)phenyl]butane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3-methylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)-3-methylphenyl]propane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]one, bis[4-(4-aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy)phenyl]ene, bis[4-(4-aminophenoxy)phenyl]ene, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether, 1,3-bis[4-(4-aminophenoxy)benzyl]benzene, 1,3-bis[4-(3-aminophenoxy)benzyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzyl]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]monene, 4,4'-bis[3-(4-aminophenoxy)benzoyl]diphenyl ether, 4,4'-bis[3-(3-aminophenoxy)phenyl]benzene [4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenyl ketone, 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenyl ketone, bis[4-{4-(4-aminophenoxy)phenoxy}phenyl] ketone, 1,4-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-trifluoromethylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-fluorophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-fluorophenoxy)-α,α-dimethylbenzyl]benzene, 1,3- bis[4-(4-amino-6-methylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-cyanophenoxy)-α,α-dimethylbenzyl]benzene, 3,3'-diamino-4,4'-diphenoxydiphenyl ketone, 4,4'-diamino-5,5'-diphenoxydiphenyl ketone, 3,4'-diamino-4,5'-diphenoxydiphenyl ketone, 3,3'-diamino-4-phenoxydiphenyl ketone, 4,4'-diamino-5-phenoxydiphenyl ketone, 3,4'-diamino-4-phenoxydiphenyl ketone, 3,4'-diamino-5'-phenoxydiphenyl ketone, 3,3'-diamino-4,4'-dibiphenoxydiphenyl ketone, 4,4'-diamino-5,5'-Diphenyloxydiphenyl ketone, 3,4'-diamino-4,5'-diphenyloxydiphenyl ketone, 3,3'-diamino-4-biphenyloxydiphenyl ketone, 4,4'-diamino-5-biphenyloxydiphenyl ketone, 3,4'-diamino-4-biphenyloxydiphenyl ketone, 3,4'-diamino-5'-biphenyloxydiphenyl ketone, 1,3-bis(3-amino-4-phenoxybenzyl)benzene, 1,4-bis(3-amino-4-phenoxybenzyl)benzene, 1,3-bis(4-amino-5-phenoxybenzyl)benzene, 1,4-bis(4-amino-5-phenoxybenzyl)benzene, 1,3-bis(3- Aromatic diamines include (amino-4-biphenoxybenzyl)benzene, 1,4-bis(3-amino-4-biphenoxybenzyl)benzene, 1,3-bis(4-amino-5-biphenoxybenzyl)benzene, 1,4-bis(4-amino-5-biphenoxybenzyl)benzene, 2,6-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzylnitrile, and aromatic diamines in which one or all of the hydrogen atoms on the aromatic ring are replaced by a halogen atom, an alkyl or alkoxy group having 1 to 3 carbon atoms, a cyano group, or an aromatic diamine in which one or all of the hydrogen atoms on the alkyl or alkoxy group have been replaced by a halogen atom, and the other is ...

[0022] Examples of the aforementioned aliphatic diamines include: 1,2-diaminoethane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, and 1,8-diaminooctane. Examples of the aforementioned alicyclic diamines include: 1,4-diaminocyclohexane and 4,4'-methylenebis(2,6-dimethylcyclohexylamine). The total amount of diamines other than aromatic diamines (aliphatic diamines and alicyclic diamines) is preferably 20% by mass or less of the total diamines, more preferably 10% by mass or less, and even more preferably 5% by mass or less. In other words, aromatic diamines are preferably 80% by mass or more of the total diamines, more preferably 90% by mass or more, and even more preferably 95% by mass or more.

[0023] As a tetracarboxylic acid constituting polyamide, the following can be used: aromatic tetracarboxylic acids (including their anhydrides), aliphatic tetracarboxylic acids (including their anhydrides), and alicyclic tetracarboxylic acids (including their anhydrides) commonly used in the synthesis of polyimides. Among these, aromatic tetracarboxylic anhydrides and alicyclic tetracarboxylic anhydrides are preferred. From the viewpoint of heat resistance, aromatic tetracarboxylic anhydrides are more preferred, and from the viewpoint of light transmittance, alicyclic tetracarboxylic acids are more preferred. When these are anhydrides, the anhydride structure in the molecule can be one or two, but it is preferred to have two anhydride structures (dianhydrides). Tetracarboxylic acids can be used alone or in combination of two or more.

[0024] Examples of alicyclic tetracarboxylic acids include cyclobutanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,3',4,4'-bicyclohexanetetracarboxylic acid, and their anhydrides. Among these, dianhydrides having two anhydride structures (e.g., cyclobutanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 3,3',4,4'-bicyclohexanetetracarboxylic acid dianhydride, etc.) are ideal. Furthermore, alicyclic tetracarboxylic acids can be used alone or in combination of two or more. When transparency is important, alicyclic tetracarboxylic acids are preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more.

[0025] The aromatic tetracarboxylic acid is not particularly limited, but pyrocalcite residues (i.e., those having a structure derived from pyrocalcite) are preferred, and its anhydride is even more preferred. Examples of such aromatic tetracarboxylic acids include: pyrocalcite dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic acid dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenyltetracarboxylic dianhydride, and 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane anhydride. When heat resistance is important, it is preferable that the aromatic tetracarboxylic acid comprises, for example, 80% by mass or more of a tetracarboxylic acid, more preferably 90% by mass or more, and even more preferably 95% by mass or more.

[0026] The thickness of the aforementioned polymer film is preferably 3 μm or more, more preferably 11 μm or more, further preferably 24 μm or more, and even more preferably 45 μm or more. There is no particular upper limit to the thickness of the aforementioned polymer film, but for use as a flexible electronic device, it is preferably 250 μm or less, more preferably 150 μm or less, and even more preferably 90 μm or less.

[0027] The average CTE of the aforementioned polymer film between 30°C and 500°C is preferably -5ppm / °C to +20ppm / °C, more preferably -5ppm / °C to +15ppm / °C, and even more preferably 1ppm / °C to +10ppm / °C. If the CTE is within the aforementioned range, the difference in linear expansion coefficient with that of a typical support (inorganic substrate) can be kept small, and peeling of the polymer film from the inorganic substrate can be avoided even in heated processes. Here, CTE represents the factor of reversible expansion and contraction with respect to temperature. Furthermore, the CTE of the aforementioned polymer film refers to the average value of the CTE in the flow direction (MD direction) and the CTE in the width direction (TD direction) of the polymer film.

[0028] The heat shrinkage rate of the aforementioned polymer film between 30°C and 500°C is preferably ±0.9%, and even more preferably ±0.6%. The heat shrinkage rate is a factor representing the irreversible stretching and contraction with respect to temperature.

[0029] The tensile breaking strength of the aforementioned polymer film is preferably 60 MPa or higher, more preferably 120 MPa or higher, and even more preferably 240 MPa or higher. There is no particular upper limit to the tensile breaking strength, but in practice it is approximately less than 1000 MPa. Furthermore, the tensile breaking strength of the aforementioned polymer film refers to the average 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.

[0030] The tensile elongation at break of the aforementioned polymer film is preferably 1% or more, more preferably 5% or more, and even more preferably 20% or more. If the aforementioned tensile elongation at break is 1% or more, the workability is excellent. Furthermore, the aforementioned tensile elongation at break of the polymer film refers to the average value of the tensile elongation at break in the flow direction (MD direction) and the tensile elongation at break in the width direction (TD direction) of the polymer film.

[0031] The aforementioned thickness non-uniformity of the polymer film is preferably below 20%, more preferably below 12%, further preferably below 7%, and especially preferably below 4%. If the thickness non-uniformity exceeds 20%, it tends to become difficult to apply to narrow areas. Furthermore, the film thickness non-uniformity can be measured, for example, by using a contact thickness gauge to randomly select approximately 10 locations on the film being measured and calculating the film thickness based on the following formula: Film thickness non-uniformity (%) = 100 × (maximum film thickness - minimum film thickness) ÷ average film thickness

[0032] It is preferable that the aforementioned polymer film is obtained by winding it into a long strip of polymer film with a width of 300 mm or more and a length of 10 m or more during its manufacturing process, and it is even more preferable that it is a roll of polymer film wound on a winding core. If the aforementioned polymer film is rolled into a roll, the transport of the rolled polymer film becomes easier.

[0033] In the aforementioned polymer film, in order to ensure operability and productivity, it is preferable to add a sliding material (particle) containing about 0.03 to 3% by mass of about 10 to 1000 nm in the polymer film to impart fine irregularities to the surface of the polymer film and ensure sliding properties.

[0034] The shape of the aforementioned polymer film is preferably a laminate. Specifically, rectangular, square or circular shapes are possible, but rectangular is preferred.

[0035] <Surface Activation Treatment of Polymer Films> The aforementioned polymer films can also undergo surface activation treatment. By performing surface activation treatment on the polymer film, the surface of the polymer film is modified to a state with functional groups (i.e., an activated state), which improves the adhesion to the inorganic substrate with the silane coupling agent. In this specification, the surface activation treatment is a dry or wet surface treatment. Examples of dry surface treatments include: vacuum plasma treatment, atmospheric pressure plasma treatment, treatment by irradiating the surface with active energy lines such as ultraviolet light, electron beams, and X-rays, corona treatment, flame treatment, and ITRO treatment. Examples of wet surface treatments include: treatment by contacting the surface of the polymer film with an acid or alkali solution.

[0036] The aforementioned surface activation treatment can also be performed in combination with other methods. This surface activation treatment cleans the surface of the polymer film and further generates active functional groups. The generated functional groups are bonded to the silane coupling agent layer described later through hydrogen bonding and chemical reactions, thereby enabling a strong bond between the polymer film, the adhesive layer derived from the silane coupling agent, and / or the adhesive layer derived from polysiloxane.

[0037] <Silane Coupling Agent Layer> The adhesive layer is formed from an adhesive layer derived from a silane coupling agent and / or an adhesive layer derived from polysiloxane. The adhesive layer can be formed by coating an inorganic substrate or by coating a polymer film. Since it can easily smooth the surface of an inorganic substrate with a large surface roughness, it is preferable to coat it onto an inorganic substrate. Details of the method for forming the adhesive layer are described in the section on the manufacturing method of the laminate.

[0038] The silane coupling agent contained in the adhesive layer derived from the silane coupling agent is not particularly limited, but it is preferable to contain a coupling agent having an amine group. Preferred examples of the aforementioned silane coupling agents include: N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, aminophenyltrimethoxysilane, aminophenylethyltrimethoxysilane, and aminophenylaminomethylphenylethyltrimethoxysilane. In applications where high heat resistance is required, aromatic groups connecting Si and amine groups are ideal.

[0039] The thickness of the silane coupling agent layer should preferably be 0.01 times or more the surface roughness (PV value) of the inorganic substrate. Since it fills in the unevenness of the inorganic substrate surface, making it easier to form a flat surface, a thickness of 0.05 times or more is preferred, more preferably 0.08 times or more, and especially preferably 0.1 times or more. There is no particular upper limit, but considering the improvement of the initial adhesion strength F0, it should preferably be 1000 times or less, more preferably 600 times or less, and even more preferably 400 times or less. By setting it within the aforementioned range, a laminate with excellent long-term heat resistance can be produced. Especially if the bonded heat-resistant polymer film is rigid and does not deform to the unevenness of the substrate surface, it is preferable to thicken the silane coupling agent layer to make the bonding surface as flat as possible. The method for measuring the thickness of the silane coupling agent layer is based on the method described in the examples. In addition, when the thickness of the silane coupling agent layer is not uniform, it is set as the thickness of the thickest part of the silane coupling agent layer.

[0040] The thickness of the silane coupling agent layer is preferably within the aforementioned range in relation to the surface roughness (PV) of the aforementioned inorganic substrate. Specifically, it is preferably 0.1 μm or more, more preferably 0.15 μm or more, and even more preferably 0.2 μm or more. Furthermore, it is preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less.

[0041] <Inorganic Substrate> The aforementioned inorganic substrate is preferably one containing a 3d metallic element (3d transition element). Specific examples of 3d metallic elements include: scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), or copper (Cu). It can be a single element metal using only these metals, or an alloy of two or more metals. It is preferable to use a plate-shaped or foil-shaped substrate containing the aforementioned metals. Specifically, SUS, copper, brass, iron, nickel, Inconel, SK steel, nickel-plated iron, nickel-plated copper, or Monel alloy are preferred. More specifically, it is preferable to use a foil selected from one or more metals including SUS, copper, brass, iron, and nickel.

[0042] In addition to the aforementioned 3d metal elements, alloys containing tungsten (W), molybdenum (Mo), platinum (Pt), or gold (Au) are also acceptable. When containing metal elements other than 3d metal elements, it is preferable that the metal containing the aforementioned 3d elements is 50% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, and especially preferably 99% by mass or more.

[0043] The laminated system of the present invention exhibits excellent long-term heat resistance even when using an inorganic substrate with a large surface roughness. Therefore, the surface roughness (PV value) of the inorganic substrate is preferably 0.1 μm or more, more preferably greater than 0.1 μm, more preferably 0.15 μm or more, even more preferably 0.2 μm or more, and particularly preferably 0.25 μm or more. Furthermore, the upper limit is preferably 20 μm or less, more preferably 19 μm or less, and more preferably 18 μm or less.

[0044] The thickness of the inorganic substrate is not particularly limited, but it is preferably 0.001 mm or more, more preferably 0.01 mm or more, and even more preferably 0.1 mm or more. Furthermore, it is preferably 2 mm or less, more preferably 1 mm or less, and even more preferably 0.5 mm or less. Within the above range, it becomes easier to use in applications such as probe cards described later.

[0045] <Laminated Body> The laminated body of the present invention sequentially laminates the aforementioned heat-resistant polymer film, the aforementioned silane coupling agent layer, and the aforementioned inorganic substrate. The adhesion strength F0 of the aforementioned laminated body when the heat-resistant polymer film is peeled off from the inorganic substrate at a 90° angle (hereinafter also referred to as the 90° peel method) is 1.0 N / cm or more and 20 N / cm or less. Furthermore, the adhesion strength F1 between the inorganic substrate and the heat-resistant polymer film in the 90° peel method (hereinafter also referred to as the long-term heat resistance test) after heating the aforementioned laminated body at 350°C for 500 hours under nitrogen atmosphere is greater than the aforementioned F0. Here, F0 is the peel strength between the heat-resistant polymer and the inorganic substrate of the laminated body after being bonded to the heat-resistant polymer film and heated at 200°C for 1 hour.

[0046] The adhesion strength F0 must be 1.0 N / cm or higher. To easily prevent accidents such as peeling or misalignment of the polymer film during device fabrication (installation), it is preferably 1.2 N / cm or higher, more preferably 1.5 N / cm or higher, and especially preferably 2.0 N / cm or higher. Furthermore, while there is no specific upper limit for the adhesion strength F0, considering the damage to the heat-resistant polymer film during peeling, it is preferably 20 N / cm or lower, preferably 15 N / cm or lower, more preferably 10 N / cm or lower, and especially preferably 5 N / cm or lower.

[0047] The bonding strength F1 must be greater than the aforementioned F0. Based on the principle that maintaining the bonding strength of the laminate after long-term heat resistance testing facilitates device fabrication and makes it easier to prevent peeling, expansion, and other adverse conditions during long-term use, the rate of increase in bonding strength (F1 / F0×100-100(%)) is preferably 1% or more, more preferably 5% or more, even more preferably 10% or more, and even more preferably 50% or more, and particularly preferably 100% or more. Furthermore, it is preferably 500% or less, preferably 400% or less, even more preferably 300% or less, and particularly preferably 200% or less.

[0048] The adhesion strength F1 is not particularly limited if it meets the aforementioned rate of increase in adhesion strength, but it is preferably greater than 1.0 N / cm. Since it becomes easier to prevent peeling accidents of the polymer film during device manufacturing, it is preferably 2 N / cm or more, more preferably 3 N / cm or more, and especially preferably 4 N / cm or more. Furthermore, the upper limit of the adhesion strength F1 is not particularly limited, but based on the damage to the heat-resistant polymer film during peeling, it is preferably 30 N / cm or less, preferably 20 N / cm or less, more preferably 15 N / cm or less, and especially preferably 10 N / cm or less.

[0049] That is, by setting the adhesion strength before and after the long-term heat resistance test within the aforementioned range, the present invention can prevent peeling accidents from the processing steps to actual use. As for the method of achieving the aforementioned adhesion strength, there is no particular limitation, but examples include: setting the ratio of the aforementioned adhesive layer to the surface roughness (PV) of the aforementioned inorganic substrate within a specified range; and setting the aforementioned adhesive layer within a specified thickness range; and suppressing the self-condensation of the silane coupling agent already coated on the inorganic substrate.

[0050] In this invention, on the surface of the inorganic substrate after the heat-resistant polymer film is peeled off at 90° from the aforementioned laminate, the area of ​​the portion peeled off at the interface between the inorganic substrate and the silane coupling agent layer must be less than 20% of the total peeling surface. Since the laminate system of this invention sequentially laminates a heat-resistant polymer film, a silane coupling agent layer, and an inorganic substrate, the following four peeling modes are foreseeable when peeling off the laminate: (1) peeling between the inorganic substrate and the silane coupling agent layer; (2) aggregation and destruction of the silane coupling agent layer; (3) peeling between the silane coupling agent layer and the heat-resistant polymer film; (4) aggregation and destruction within the heat-resistant polymer film. In this invention, the area of ​​the portion peeled off between the inorganic substrate and the silane coupling agent layer in (1) must be less than 20% of the total peeling surface. Because the silane coupling agent layer is uniformly formed between the inorganic substrate and the heat-resistant polymer film, the adhesion of each layer of the laminate becomes uniform, and the unevenness between strong and weak adhesion areas is reduced, preferably to 15% or less. When the silane coupling agent layer is not uniformly formed on the inorganic substrate, island structures can be seen on the surface of the inorganic substrate after the heat-resistant polymer film is peeled off at a 90° angle from the laminate. There may be cases where the area of ​​the peeled portion at the interface between the inorganic substrate and the silane coupling agent layer exceeds 20% of the total peeled surface. On the other hand, when the silane coupling agent layer is uniformly formed and the bonding surface is sufficiently smooth, island structures are not seen, and the area of ​​the peeled portion at the interface between the inorganic substrate and the silane coupling agent layer is less than 20% of the total peeled surface. When the area of ​​the peeled portion at the interface between the inorganic substrate and the silane coupling agent layer is less than 20%, there is no unevenness in peel strength and adhesion between the inorganic substrate and the heat-resistant polymer film, and the occurrence of bubble protrusions can be suppressed after lamination and when the laminate is heated at high temperature. Since the area of ​​the peeled portion at the interface between the inorganic substrate and the silane coupling agent layer is as small as possible, 0% is preferred, but for industrial purposes, 1% or more is preferred, and 2% or more is also acceptable.

[0051] In the present invention, the manufacturing of the aforementioned laminate includes at least the following steps: (1) coating a silane coupling agent onto at least one side of an inorganic substrate; (2) overlapping the silane coupling agent coated surface of the aforementioned inorganic substrate with a heat-resistant polymer film; and (3) applying pressure to the aforementioned inorganic substrate and the heat-resistant polymer film. Using the same coating method as step (1), the aforementioned silane coupling agent is coated onto a KBr (potassium bromide) plate to create a coated plate. In the spectrum obtained by measurement using micro-infrared spectroscopy (transmission method), the area of ​​peaks originating from various functional groups (functional group as a whole) is preferably 15 or less. More preferably, it is 10 or less. Furthermore, the lower limit is not particularly limited; it is preferably 1 or more, and may also be 2 or more. In this invention, since it is impossible to directly measure the silane coupling agent coated on the inorganic substrate using micro-infrared spectroscopy, the KBr plate is considered an inorganic substrate, and the KBr coated plate is measured using micro-infrared spectroscopy. Specifically, a predetermined processing is performed on the spectrum obtained by micro-infrared spectroscopy, and the value of the wavenumber range 3400cm-1 to 2400cm-1, which uses 3400cm-1 and 2400cm-1 as base points corresponding to various functional groups (functional group as a whole) (see Figure 6(a)), is subtracted from the area of ​​the wavenumber range 3000cm-1 to 2770cm-1, which uses 3000cm-1 and 2770cm-1 as base points corresponding to hydrocarbons (see Figure 6(b)), which is taken as the peak area originating from the functional groups. More specifically, the peak area is calculated using the method described in the examples. In the spectra obtained by measuring the KBr-coated plate using micro-infrared spectroscopy, when the area of ​​the peaks originating from functional groups is 15 or less, the silane coupling agent has few functional groups, making it difficult for the silane coupling agent on the inorganic substrate to undergo self-condensation, thus facilitating a uniform reaction with the heat-resistant polymer film. For example, when the heat-resistant polymer film is a polyimide film, the carbonyl groups of polyimide readily react uniformly with the alkoxy groups of the silane coupling agent. Regarding the spectra obtained by measuring the KBr-coated plate using micro-infrared spectroscopy, a method to set the area of ​​the peaks originating from functional groups to 15 or less can be exemplified by promoting the silanization of methoxy groups during silane coupling agent coating. Specifically, this is achieved by generating tiny silane coupling agent droplets through heating and ultrasonic irradiation, which are then sprayed onto the KBr (inorganic substrate). Using either a stock solution or solvents such as water and alcohol, the silanyl coupling agent can be coated onto an inorganic substrate, and silanization can continue even when the substrate is exposed to moisture. By creating micro-droplets, the surface area of ​​the silanyl coupling agent is increased, resulting in an effectively silanized state. Furthermore, by controlling the heating temperature and coating time of the silanyl coupling agent, a large amount of the agent can be coated onto the inorganic substrate.By increasing the amount of silane coupling agent applied, the temporarily micro-dropletized, silanol-modified silane coupling agent becomes liquid on the inorganic substrate. Since the unevenness of the inorganic substrate surface is covered by the liquid silane coupling agent, the surface of the inorganic substrate is smoothed, allowing for uniform bonding of the inorganic substrate and the heat-resistant polymer film without deviation.

[0052] The lamination system of the present invention can be fabricated, for example, using the following sequence. At least one side of an inorganic substrate is first treated with a silane coupling agent, the silane-coated side is overlapped with a polymer film, and the two are pressed together to obtain a laminate. Alternatively, at least one side of a polymer film is first treated with a silane coupling agent, the silane-coated side is overlapped with an inorganic substrate, and the two are pressed together to obtain a laminate. Examples of silane coupling agent treatment methods include: vaporization (micro-dropletization) of the silane coupling agent for coating (vapor phase coating), or spin coating and hand coating methods where the silane coupling agent is kept in its original solution or dissolved in a solvent. Alternatively, water vapor and gaseous silane coupling agent can be sprayed together onto the inorganic substrate, or water vapor can be sprayed onto the inorganic substrate treated with the silane coupling agent. Ultrasonic irradiation and heating are effective in vaporizing the silane coupling agent; by increasing the ultrasonic output and heating temperature, a large amount of silane coupling agent can be vaporized. Specifically, if a silane coupling agent with a boiling point above 200°C is used, the heating temperature should preferably be above 50°C. Furthermore, when using vaporized silane coupling agent, it is preferable that the injection port of the silane coupling agent be as close as possible to the inorganic substrate; for example, it is preferable to place the silane coupling agent in a container, heat it, and fix the inorganic substrate to the top of the container. This is because the silane coupling agent, after vaporization, inhibits self-condensation during its journey to the inorganic substrate, resulting in a large volume of silane coupling agent being sprayed. Even when using a spray nozzle, the shorter the distance from the spray nozzle to the inorganic substrate, the better, preferably less than 20 cm. Furthermore, as a pressurization method, examples include: normal pressing or lamination in the atmosphere, or pressing or lamination in a vacuum. To obtain stable adhesion strength across the entire surface, large-size laminates (e.g., exceeding 200 mm) are preferably laminated in the atmosphere. In contrast, for small-size laminates of approximately 200 mm or less, vacuum pressing is preferred. The vacuum level is sufficient using a conventional rotary pump, such as approximately 10 Torr or less. A preferred pressure is 1 MPa to 20 MPa, more preferably 3 MPa to 10 MPa. High pressure may cause substrate damage, while low pressure may result in areas of insufficient adhesion. The optimal temperature is 90°C to 300°C, and more preferably 100°C to 250°C. If the temperature is too high, it will damage the polymer film, and if the temperature is too low, the adhesion will be weakened.

[0053] The shape of the aforementioned laminated body may include rectangle, square, or circle, with rectangle being preferred. The area of ​​the aforementioned laminated body should preferably be 0.01 square meters or more, preferably 0.1 square meters or more, more preferably 0.7 square meters or more, and especially preferably 1 square meter or more. Furthermore, based on ease of manufacture, it should preferably be 5 square meters or less, preferably 4 square meters or less. When the shape of the laminated body is rectangular, the length of one side should preferably be 50 mm or more, preferably 100 mm or more. Furthermore, there is no particular upper limit, but it should preferably be 1000 mm or less, preferably 900 mm or less.

[0054] The laminated system of the present invention can be used in components such as probe cards, flat cables, heating elements (insulated heaters), electrical and electronic substrates, or solar cells (backsheets for solar cells). By using the laminated body of the present invention in the aforementioned applications, it is possible to achieve simplified processing conditions (expanded process window) and increased service life. [Example]

[0055] <Preparation of Polyacrylic Acid Solution A> After replacing the nitrogen gas in a reaction vessel equipped with a nitrogen inlet tube, thermometer, and stir bar, 223 parts by mass of 5-amino-2-(p-aminophenyl)benzo[a]azole (DAMBO) and 4416 parts by mass of N,N-dimethylacetamide were added and completely dissolved. Next, while adding 217 parts by mass of pyrocalcite dianhydride (PMDA), a dispersion (Nissan Chemical Industries, Ltd. "Snowtex (registered trademark) DMAC-ST30") made by dispersing colloidal silica in dimethylacetamide was added as a lubricant at a ratio of 0.12% by mass of the total polymer solids in the polyacrylic acid solution. The mixture was stirred at a reaction temperature of 25°C for 24 hours to obtain a brown and viscous polyacrylic acid solution A.

[0056] <Preparation of Heat-Resistant Polymer Film F1> The polyacrylic acid solution A obtained above was coated onto the smooth surface (non-slip agent side) of a long strip polyester film (Toyobo Co., Ltd. "A-4100") with a final film thickness (film thickness after amide maturation) of 15 μm using a die-casting method. After drying at 105°C for 20 minutes, it was peeled off from the polyester film to obtain a self-supporting polyacrylic acid film with a width of 920 mm. The two ends of the polyacrylic acid film obtained above were held by a pin tenter and subjected to heat treatment of 150°C for 5 minutes, 220°C for 5 minutes, and 550°C for 10 minutes to amide maturate it. The pin-held portions at both ends were cut off using a cutting machine to obtain a long strip heat-resistant polymer film (F1) (1000 m roll) with a width of 850 mm.

[0057] <Vacuum Plasma Treatment of Heat-Resistant Polymer Film F1 (Preparation of Heat-Resistant Polymer Film F2)> Vacuum plasma treatment was performed on the heat-resistant polymer film F1 under the following conditions. The vacuum plasma treatment was performed using a strip film processing apparatus. The vacuum chamber was evacuated until the pressure reached below 1×10-3 Pa. Argon gas was introduced into the vacuum chamber, and argon plasma treatment was performed for 20 seconds at a discharge power of 100W and a frequency of 15kHz to obtain the heat-resistant polymer film F2.

[0058] <Preparation of Heat-Resistant Polymer Films F3 and F4> Heat-resistant polymer films F3 and F4 are manufactured using the same plasma treatment process as heat-resistant polymer film F2 on commercially available polyimide films. F3: UPILEX (registered trademark) 25S (polyimide film manufactured by Ube Industries, Ltd., 25μm thickness) F4: KAPTON (registered trademark) 100H (polyimide film manufactured by Toray Industries, DuPont, Ltd., 25μm thickness)

[0059] <Inorganic Substrate> As an inorganic substrate, the following metal substrates are used. The metal substrates used are SUS304 (manufactured by Kenis Corporation), copper plate (manufactured by Kenis Corporation), rolled copper foil (manufactured by Mitsui Sumitomo Metal Mining Shindō Co., Ltd.), SK steel (manufactured by Kenis Corporation), nickel-plated iron (manufactured by Kenis Corporation), nickel-plated copper (manufactured by Kenis Corporation), aluminum plate (manufactured by Kenis Corporation), Inco nickel foil (manufactured by As One Corporation), iron plate (manufactured by As One Corporation), brass plate (manufactured by As One Corporation), and Monel alloy plate (manufactured by As One Corporation). Hereinafter, they are also referred to as substrates or base materials.

[0060] <Cleaning of Inorganic Substrate> The inorganic substrate is subjected to the following steps in sequence: degreasing with acetone, ultrasonic cleaning in pure water, and UV / ozone irradiation for 3 minutes on the surface where the silane coupling agent layer is formed.

[0061] <Forming of silane coupling agent layer for substrate> Using the aforementioned substrate as substrate, a silane coupling agent layer (adhesive layer) is formed using the following method.

[0062] <Coating Example SC1> In a chamber 16 equipped with an exhaust duct 18, a substrate cooling stage 20, and a silane coupling agent injection nozzle 15, a suction bottle 19 filled with 100 parts by weight of silane coupling agent KBM-903 (Shin-Etsu Silicon Power, 3-aminopropyltrimethoxysilane) is connected via a silicone tube and then placed in an ultrasonic treatment bath 50 heated to 45°C. Instrument air is introduced from above the suction bottle 19 and the chamber is sealed, allowing silane coupling agent vapor to be introduced into the chamber 16 (Fig. 1). The inorganic substrate 17 is placed horizontally on the substrate cooling stage 20 with the UV irradiation surface facing upwards, and the chamber 16 is closed. The distance between the inorganic substrate 17 and the silane coupling agent injection nozzle 15 is set to 10 mm. Next, the instrument air was introduced at a rate of 20 L / min, and the inorganic substrate 17 was exposed to silane coupling agent vapor for 3 minutes to obtain a silane coupling agent coated substrate.

[0063] <Coating Example SC2> In a chamber 16 equipped with an exhaust duct 18, a substrate cooling stage 20, and a silane coupling agent injection nozzle 15, a suction bottle 19 filled with 100 parts by weight of silane coupling agent KBM-903 (Shin-Etsu Silicone, 3-aminopropyltrimethoxysilane) is connected via a silicone tube and then placed in a water bath 24 heated to 60°C. The chamber is sealed so that instrument air can be introduced from above the suction bottle 19, and silane coupling agent vapor can be introduced into the chamber 16 (Fig. 2). The inorganic substrate 17 is placed horizontally on the substrate cooling stage 20 with the UV irradiation surface facing upwards, and the chamber 16 is closed. The distance between the inorganic substrate 17 and the silane coupling agent injection nozzle 29 is set to 5 mm. Next, the instrument air was introduced at a rate of 20 L / min, and the inorganic substrate 17 was exposed to silane coupling agent vapor for 3 minutes to obtain a silane coupling agent coated substrate.

[0064] <Coating Example SC3> As shown in Figure 3, 100 parts by weight of silane coupling agent KBM-903 (Shin-Etsu Silicon Power, 3-aminopropyltrimethoxysilane) were filled onto the metal gasket 32 ​​and heated to 60°C using heater 25. The inorganic substrate 17 was exposed to the generated silane coupling agent vapor for 5 minutes to obtain a silane coupling agent coated substrate.

[0065] <Coating Example SC4> In a chamber 16 equipped with an exhaust duct 18 and a substrate cooling stage 20, a suction bottle 19 filled with 100 parts by weight of silane coupling agent KBM-903 (Shin-Etsu Silicon Power, 3-aminopropyltrimethoxysilane) is connected via a silicone tube and then placed in a water bath 24 heated to 50°C. The chamber is sealed so that instrument air can be introduced from above the suction bottle 19, and silane coupling agent vapor can be introduced into the chamber 16 (Fig. 4). The inorganic substrate 17 is placed horizontally on the substrate cooling stage 20 with the UV irradiation surface facing upwards, and the chamber is closed. The substrate temperature is 17°C, and the distance between the inorganic substrate and the silane coupling agent spray nozzle is 5 mm. Next, instrument air is introduced at a rate of 20 L / min, exposing the inorganic substrate 17 to silane coupling agent vapor for 3 minutes. Then, water vapor is introduced into the chamber through the water vapor inlet 42 for 2 minutes to obtain a silane coupling agent coated substrate. The water vapor is introduced as follows: a suction bottle (not shown) filled with 100 parts by weight of pure water is connected to the water vapor inlet via a silicone tube. The suction bottle is preheated in a water bath at 60°C. Simultaneously with the completion of the silane coupling agent coating, instrument air flows in from above the suction bottle.

[0066] The pure water system should preferably be of Class 1 or higher according to the standards set forth in ISO 3696-1987. Class 3 is more preferred. The pure water system used in this invention is of Class 1.

[0067] <Coating Example SC5> Except that KBE-903 (Shin-Etsu Silicon Power, 3-aminopropyltriethoxysilane) was used instead of KBM-903, the coating was processed in the same way as SC1.

[0068] <Coating Example SC6> Except that KBM-903 was replaced with KBM-603 (Shin-Etsu Silicon Power, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane), it was treated in the same way as SC1.

[0069] <Coating Example SC7> In a chamber 16 equipped with an exhaust duct 18 and a substrate cooling stage 20, a suction bottle 19 filled with 100 parts by weight of silane coupling agent KBM-903 (Shin-Etsu Silicone, 3-aminopropyltrimethoxysilane) is connected via a silicone tube and then placed in a water bath 24 heated to 40°C. Instrument air is introduced from above the suction bottle 19 and the chamber is sealed, allowing silane coupling agent vapor to be introduced into the chamber 16 (Fig. 5). The inorganic substrate 17 is placed horizontally on the substrate cooling stage 20 with the UV irradiation surface facing upwards, and the chamber 16 is closed. The set temperature of the stage 20 is set to 17°C. Next, instrument air is introduced at a rate of 20 L / min, exposing the inorganic substrate 17 to the silane coupling agent vapor for 3 minutes to obtain a silane coupling agent coated substrate.

[0070] <Coating Example SC8> An inorganic substrate is placed in a spin coater (manufactured by JAPANCREATE, MSC-500S), and the rotation speed is increased to 2000 rpm. After rotating for 10 seconds, a silane coupling agent (KBM-903) stock solution is coated to obtain a silane coupling agent coated substrate.

[0071] <Coating Example SC9> A silane coupling agent diluent diluted with isopropanol was prepared by including 1% by mass of silane coupling agent (KBM-903). An inorganic substrate was placed on a spin coater (JAPANCREATE, MSC-500S) and the spin speed was increased to 2000 rpm for 10 seconds to coat the silane coupling agent diluent. Next, the substrate coated with silane coupling agent was placed on a hot plate heated to 110°C with the silane coupling agent coating surface facing up, and heated for about 1 minute to obtain a silane coupling agent coated substrate.

[0072] <Fabrication of the laminate: Laminate> The silane coupling agent coated surface of the inorganic substrate is overlapped with a heat-resistant polymer film, and bonded using pressure. During bonding, a laminator (MCK MRK-1000) is used, and the bonding conditions are set as follows: air pressure: 0.7 MPa, temperature: 22°C, humidity: 55%RH, and lamination speed: 50 mm / second. The resulting inorganic substrate / silane coupling agent / heat-resistant polymer film laminate is heated at 200°C for 1 hour under atmospheric conditions to obtain a laminate having an inorganic substrate, a silane coupling agent layer, and a heat-resistant polymer film in sequence. Subsequently, a 90° peel test (F0) is performed. Next, a laminate prepared after the aforementioned heat treatment (200°C, 1 hour) is heat-treated at 350°C in a nitrogen atmosphere for 500 hours, and a 90° peel test (F1) is performed. The evaluation results are shown in Table 1.

[0073] <90° Peel Test (90° Peel Method)> A 90° peel test was conducted using a JSV-H1000 manufactured by a Japanese measurement system. The polymer film was peeled off at a 90° angle relative to the substrate, with a test (peeling) speed set to 100 mm / min. The sample size was set to be at least 10 mm wide and 50 mm long. The test was conducted in an atmospheric environment at room temperature (25°C). Five tests were performed, and the average peel strength of the five tests was used as the result.

[0074] <Long-term heat resistance test> The sample (laminated body) was stored for 500 hours under nitrogen atmosphere and heated to 350°C. For the heat treatment, a high-temperature inert gas oven INH-9N1 manufactured by Koyo Thermal Systems Co., Ltd. was used.

[0075] <Appearance after Long-Term Heat Resistance Test> The laminate after the long-term heat resistance test was visually observed, and the number of impurity-free bubbles with a diameter of 1 mm or more that served as nuclei between the inorganic substrate and the heat-resistant polymer film was counted. Bubbles with impurities serving as nuclei are caused by impurities that were trapped between the inorganic substrate and the heat-resistant polymer film during lamination, and therefore are unrelated to the uniformity of the silane coupling agent reaction, and are removed from the evaluation. The presence or absence of impurities was confirmed using a magnifying glass and a KEYENCE VH-Z100R microscope. Bubbles with a diameter of 1 mm or more that served as nuclei were rated as ○ if 4 or less / m², and × if 5 or more / m².

[0076] <Evaluation of the Thickness of the Silicon Coupling Agent Layer> Thin film samples of the laminate cross-section were prepared using an integrated ion beam apparatus (FIB), and the thickness of the silicon coupling agent layer was determined by observation at 5000x using a transmission electron microscope (TEM) manufactured by NJE. Measurements were taken at three points along a 10cm length of the laminate, and the average value was used. When the thickness of the silicon coupling agent layer was uneven within a single field of view due to the unevenness of the substrate, the thinnest point was taken as the thickness of the silicon coupling agent layer.

[0077] <Evaluation of Substrate Surface Roughness> The surface roughness (PV value) of the substrate was measured using a LASERTEC microscope (product name: OPTELICS HYBRID). The PV value of the substrate was measured from a 400 μm cross-sectional image avoiding impurities and obvious defects at a magnification of 50x. The evaluation was performed on one point of the sample in one observation area.

[0078] <Observation of the Peel-off Surface> The heat-resistant polymer film was peeled off from the laminate at 90°. The inorganic substrate side was observed at 5x magnification using a LASERTEC microscope (product name: OPTELICS HYBRID) to confirm the presence or absence of island structures. ESCA analysis was performed on both the inorganic substrate side and the heat-resistant polymer film side to evaluate whether the peel-off surface was the interface between the inorganic substrate and the silane coupling agent. The apparatus used was K-Alpha+ (Thermo Fisher Scientific). The measurement conditions are as follows. In addition, background removal was performed using the Shirley method during analysis. Furthermore, the surface composition ratio was set as the average of the measurement results from at least 3 locations. When island structures were observed on the inorganic substrate side, measurements were performed at least 3 locations on both the sea and island sides. • Measurement conditions Excitation X-rays: Monochromatic Al Kα rays X-ray output: 12kV, 6mA Photoelectron detachment angle: 90° Spot size: 400μmϕ Path energy: 50eV Step: 0.1eV

[0079] An image of the peeled surface (inorganic substrate) was observed at 5x magnification using a LASERTEC microscope (product name: OPTELICS HYBRID) to determine the area peeled at the interface between the inorganic substrate and the silane coupling agent. The observation conditions were set as follows: scanning resolution energy 0.33 μm, CCD mode: color, exposure time: standard, and light source intensity 20%. The results of ESCA measurements were used to determine whether any part of the island was peeled at the interface between the inorganic substrate and the silane coupling agent. Areas where the elemental percentage of the inorganic substrate was 4% or higher were considered to be peeled at the interface between the inorganic substrate and the silane coupling agent. The obtained image was converted to 8-bit monochrome format using ImageJ, with minimum display: 127, maximum display value: 128, and threshold values ​​of 44 and 124, to determine the area of ​​the island and the sea.

[0080] <Microscopic Infrared Spectrophotometry Measurement of Silicon Coating Surface> Silicon coupling agent was coated onto a KBr plate according to methods SC1 to SC9, and microscopic infrared spectrophotometry (transmission method) was performed. The silicon coupling agent coated substrate was immediately placed in an aluminum bag after coating and stored under nitrogen purging until the measurement. Furthermore, when using a spin coater, the KBr plate was temporarily fixed on a 10cm × 10cm glass plate for coating. The horizontal axis was set as wavenumber (cm⁻¹) and the vertical axis as absorbance (au). The spectrum obtained by microscopic infrared spectrophotometry (hereinafter also referred to as preliminary data) was processed as follows. The peak (maximum value) of the silane coupling agent (Si-O-Si) originating near 1030 cm⁻¹ is aligned to 0.055 (au), and the trough (minimum value) near 840 cm⁻¹ is aligned to 0.012 (au) (hereinafter also referred to as processing data). Using the following apparatus, the spectrum of the preliminary data can be easily converted into processing data. First, the spectrum of the obtained preliminary data is expressed on a full scale in the range of 1070 cm⁻¹ to 800 cm⁻¹. Then, the absorbance of the aforementioned maximum value is aligned to 0.055 (au), and the absorbance of the minimum value is aligned to 0.012 (au) to obtain the processing data. Regarding the obtained processing data, the peak area derived from the functional groups was calculated using analytical software by subtracting the area of ​​the wavenumber range 3400cm⁻¹ to 2400cm⁻¹, which uses 3400cm⁻¹ and 2400cm⁻¹ as base points for various functional groups (functional groups as a whole), from the area of ​​the wavenumber range 3000cm⁻¹ to 2770cm⁻¹, which uses 3000cm⁻¹ and 2770cm⁻¹ as base points for hydrocarbons. The following apparatus was used for measurement, spectral processing, and analysis: Micro-infrared spectrophotometry (transmission method) apparatus: Cary 670FTIR (Agilent Technologies, Inc.); Peak height adjustment: Resolutions Pro analytical software attached to the micro-infrared spectrophotometry (transmission method) apparatus; Varian Resolutions Pro 4.0.

[0081] <Example 1> Using the above-mentioned SUS304 (substrate thickness 0.5 mm) as the substrate, a silane coupling agent layer was formed by the SCI method, and a heat-resistant polymer film F1 was used to fabricate a laminate according to the method of laminate fabrication example 1. The evaluation results are shown in Table 1.

[0082] <Examples 2-17 and Comparative Examples 1-4> Examples 2-17 and Comparative Examples 1-4 were carried out in accordance with the conditions set out in Tables 1-2.

[0083] [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Heat-resistant polymer film F1 F1 F1 F1 F1 F2 F3 F4 F1 F1 F1 Next, the layering method and coating method SC1 SC1 SC1 SC1 SC1 SC1 SC1 SC1 SC2 SC2 SC2 Next, the amount of SCA (silane coupling agent) is added. KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 KBM-903 The delamination at the interface between the inorganic substrate and the silane coupling agent layer Area of ​​part (%) 7 8 9 10 9 5 8 9 0 3 2 Thickness of silane coupling agent layer (nm) 410 380 410 350 380 370 380 380 310 350 330 substrate SUS Ingol nickel foil iron brass SK Steel SUS SUS SUS SUS copper Nickel-plated copper Substrate thickness (mm) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Inorganic substrate (lamination surface) PV value (μm) 0.76 0.31 1.5 1.7 1.8 0.76 0.76 0.76 0.76 15.2 1.4 F0(N / cm) 2.4 2.8 2.9 2.7 2.9 3.1 3.5 4 3.4 2.4 2.8 F1(N / cm) 7 7 6 7 7 6.5 7.7 7 8 6 6 Next, the rate of increase in intensity 191.7 150.0 106.9 159.3 141.4 109.7 120.0 75.0 135.3 150.0 114.3 Area derived from the peak of functional groups 7.7 8.2 7.5 7.6 8 8.1 9.1 9.4 5.9 7.7 6.5 Appearance after prolonged heating ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

[0084] [Table 2] Example 12 Example 13 Example 14 Example 15 Example 16 Example 17 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Heat-resistant polymer film F1 F1 F1 F1 F2 F2 F3 F4 F4 F4 Next, the layering method and coating method SC2 SC2 SC3 SC4 SC5 SC6 SC7 SC8 SC9 SC7 Next layer (SCA amount) KBM-903 KBM-903 KBM-903 KBM-903 KBE-903 KBM-603 KBM-903 KBM-903 (original solution) KBM-903 (IPA) KBM-903 The delamination at the interface between the inorganic substrate and the silane coupling agent layer Area of ​​part (%) 3 1 15 11 7 8 61 77 34 18 Thickness of silane coupling agent layer (nm) 460 330 250 230 350 350 32 48 68 20 substrate Nickel-plated iron Rolled copper foil SUS SUS SUS SUS SUS copper SUS SUS Substrate thickness (mm) 0.5 0.06 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Inorganic substrate (lamination surface) PV value (μm) 1.8 3.04 0.76 0.76 0.76 0.76 0.76 51.2 0.76 0.76 F0(N / cm) 2.2 2.8 2.4 2.1 2.3 2.2 1.5 0.3 1.5 0.1 F1(N / cm) 7 5 5 5 6 6.5 2.7 Local peeling 2 Local peeling Next, the rate of increase in intensity 218.2 78.6 108.3 138.1 160.9 195.5 80.0 - 33.3 - Area derived from the peak of functional groups 7.2 8.3 9.9 7.2 9.8 9.9 27 25 twenty one 27 Appearance after prolonged heating ○ ○ ○ ○ ○ ○ × × × (Partial peeling) Local peeling [Potential for industrial application]

[0085] By using the laminate of the present invention, the processing conditions for probe cards, flat cables, heaters (insulating type), electrical and electronic substrates, backlight panels for solar cells, etc., can be eased (process window expanded) and the service life increased. Furthermore, if it is a roll-shaped laminate, transportation and storage are convenient. [Simplified Explanation of the Diagram]

[0013] FIG1 is a schematic diagram showing an example of a silane coupling agent coating apparatus according to one embodiment of the present invention. In the apparatus of FIG1, a silane coupling agent injection nozzle and an ultrasonic treatment tank are provided. FIG2 is a schematic diagram showing an example of a silane coupling agent coating apparatus according to another embodiment of the present invention. In the apparatus of FIG2, a silane coupling agent injection nozzle and a water bath are provided. FIG3 is a schematic diagram showing an example of a silane coupling agent coating apparatus according to yet another embodiment of the present invention. In the apparatus of FIG3, a metal gasket is provided. FIG4 is a schematic diagram showing an example of a silane coupling agent coating apparatus according to yet another embodiment of the present invention. In the apparatus of FIG4, a silane coupling agent inlet and a water vapor inlet are provided. FIG5 is a schematic diagram showing an example of a silane coupling agent coating apparatus according to yet another embodiment of the present invention. In the apparatus of FIG5, a silane coupling agent inlet is provided. Figure 6 shows the micro-infrared spectrophotometer of the silane coupling agent coated plate obtained in Example 9. Figure 6(a) shows the area enclosed by the straight line and the spectral waveform line obtained by aligning the height of the peak near 1030 cm⁻¹ by 0.055 (au) and the height of the trough (minimum) near 840 cm⁻¹ by 0.012 (au) to connect the peaks at 3400 cm⁻¹ and 2400 cm⁻¹. Figure 6(b) shows the area enclosed by the straight line and the spectral waveform line obtained by adjusting the peak height in the same way as in Figure 6(a) to connect the peaks at 3000 cm⁻¹ and 2770 cm⁻¹.

Claims

1. A laminate, characterized in that it sequentially comprises an inorganic substrate, a silane coupling agent layer, and a heat-resistant polymer film, wherein the thickness of the silane coupling agent layer is at least 0.01 times the surface roughness (PV value) of the inorganic substrate, and satisfies the following (A) to (C): (A) The peel strength F0 when the heat-resistant polymer film is peeled from the inorganic substrate at 90° is more than 1.0 N / cm and less than 20 N / cm; (B) On the surface of the inorganic substrate after the heat-resistant polymer film is peeled from the inorganic substrate at 90°, the area of ​​the peeled portion at the interface between the inorganic substrate and the silane coupling agent layer is less than 20% of the entire peeled surface; (C) After heating the laminate at 350°C for 500 hours in a nitrogen atmosphere, the peel strength F1 when the heat-resistant polymer film is peeled from the inorganic substrate at 90° is greater than F0.

2. The laminate as claimed in claim 1, wherein the inorganic substrate comprises 3D metallic elements.

3. The laminate as claimed in claim 1 or 2, wherein the inorganic substrate is one or more selected from the group consisting of SUS, copper, brass, iron and nickel.

4. The laminate as claimed in claim 1 or 2, wherein the heat-resistant polymer film is a polyimide film.

5. A probe card comprising, in its constituent elements, a stack as claimed in any one of claims 1 to 4.

6. A flat cable comprising, in its constituent elements, a laminate as claimed in any one of claims 1 to 4.

7. A heating element comprising, in its constituent parts, a laminate as claimed in any one of claims 1 to 4.

8. An electrical and electronic substrate comprising, in its constituent components, a laminate as claimed in any one of claims 1 to 4.

9. A solar cell comprising, in its constituent parts, a laminate as claimed in any one of claims 1 to 4.

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