TWI735421B - Laminate, production method and use method thereof, and polymide precursor solttion for lamination on alkali free glass substrate - Google Patents

Abstract

The objection of the present invention is to provide a laminate comprising a polyimide film and a glass substrate, wherein the laminate has good peeling properties and curl of the peeled polyimide film is reduced, when the polyimide film is peeled from the glass substrate. The present invention relates to a laminated product comprising a glass substrate and a polyimide film including a filler-containing polyimide layer formed on the glass substrate, wherein the filler has a coefficient of thermal expansion of 10 ppm/℃ or less.

Description

Laminated body, its manufacturing method and its use method, and polyimide precursor solution for alkali-free glass substrate laminating

The present invention relates to a laminated body, particularly a laminated body including a polyimide layer (film) with excellent heat resistance and dimensional stability and an alkali-free glass substrate, its manufacturing method and use method, and an alkali-free glass substrate Polyimide precursor solution for buildup (polyimide precursor solution for polyimide film formation).

Conventionally, it is mainly used in the fields of flat panel displays (FPD) such as liquid crystal displays (LCD), plasma display panels (PDP), organic electroluminescence (EL, electroluminescence) displays (OLED), and electronic devices such as electronic paper Where electronic components are formed on a glass substrate, there is a problem that it is difficult to become flexible due to the rigidity of the glass substrate and lack of flexibility.

Therefore, a method has been proposed in which a laminate obtained by laminating and integrating an organic polymer material such as polyimide, which has flexibility, good heat resistance and dimensional stability, and a glass substrate, is used as a substrate.

In Patent Documents 1 to 3, it is proposed that a polyimide film with a lower coefficient of thermal expansion (CTE) is formed on a glass substrate and laminated and integrated, and it is used as a substrate for forming electronic components. Here, the CTE of polyimine is one of the indicators of the dimensional stability of polyimine. Alkali-free glass base The CTE of the board), the smaller the strain of the polyimide generated at the interface of the laminated body during the high-temperature treatment in the electronic component formation step, the more improved the dimensional stability of the polyimide film.

As the above-mentioned low thermal expansion coefficient (CTE) polyimide, it is known from 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) and other aromatic tetracarboxylic acids and p-phenylenediamine (PDA) ) Polyimine obtained from aromatic diamines has a low CTE and excellent heat resistance.

In such a glass substrate laminated with a polyimide film, when the glass substrate is used as a carrier substrate, the surface of the polyimide film can be used to form electronic components and finally peel off from the glass substrate Polyimide is coated with a film to make a flexible substrate.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2002-297054

[Patent Document 2] Japanese Patent Laid-Open No. 2012-35583

[Patent Document 3] Japanese Patent Laid-Open No. 2014-205327

However, the polyimide coating system disclosed in the prior art is difficult to sufficiently reduce the CTE, and its dimensional stability is insufficient. Therefore, there is a problem that, for example, the polyimide film peeled from the glass substrate is likely to curl. The smaller the radius of curvature of the curl, the more complicated the operation of polyimide coating will be, which will cause problems in workability. In addition, the peeling characteristics of the polyimide film from the glass substrate are also insufficient.

Therefore, the present invention solves the above-mentioned problems, and its object is to provide a laminate, a method of manufacturing and using the laminate, and a polyimide precursor for glass substrate laminates capable of forming such a polyimide film Solution, the laminated system includes polyimide film and glass substrate, when the polyimide film is peeled from the glass substrate, it has good peeling characteristics, and the peeled polyimide film is not easy to curl.

The inventors of the present invention have intensively studied to solve the above-mentioned problems, and as a result, they have found that the above-mentioned laminate has a structure of a polyimide coating as a specific one in a laminate including a glass substrate and a polyimide coating. The above-mentioned problems can be solved, and the present invention has been completed.

That is, the present invention has the following content as its main purpose.

(1) A laminated body comprising a glass substrate and a polyimide film including a polyimide layer containing a filler formed on the glass substrate, characterized in that the thermal expansion coefficient of the filler is 10 ppm/ ℃ below.

(2) The laminate according to (1), wherein the polyimide coating film includes the polyimide layer containing the filler, and the polyimide layer without filler formed on the polyimide layer containing the filler. The imine layer.

(3) The laminate according to (1) or (2), wherein the filler is one or more fillers selected from the group consisting of carbon particles, ceramic particles, and silicon particles.

(4) A method for manufacturing a laminate, which is the method for manufacturing a laminate as described in any one of (1) to (3), characterized by coating a filler-containing polyimide precursor on a glass substrate The solution is dried and heat-treated to form a filler-containing polyimide layer.

(5) A method of using laminates, characterized in that: any one of (1) to (3) The laminated body described is used in the manufacture of electronic devices.

(6) A polyimide precursor solution for glass substrate lamination, characterized in that it contains a filler with a thermal expansion coefficient of 10 ppm/°C or less.

The polyimide coating film of the laminate of the present invention is not easy to curl because the CTE of the polyimide coating film in contact with the glass substrate is sufficiently low. Even if it is curled, the radius of curvature of the curl is sufficiently large. In addition, the laminate of the present invention can be suitably used as a laminate when manufacturing electronic devices such as flat panel displays and flexible devices because the polyimide coating film has good peelability.

Hereinafter, the present invention will be described in detail

[Layered body]

The laminated system of the present invention includes a glass substrate and a polyimide film. As the glass substrate, for example, a substrate containing soda lime glass, borosilicate glass, or alkali-free glass can be used. Among these, an alkali-free glass substrate can be preferably used. These glass substrates can also be subjected to well-known surface treatments such as silane coupling agent treatment.

The thickness of the glass substrate is preferably 0.3 to 5.0 mm. If the thickness is thinner than 0.3mm, there may be a case where the substrate is rationally degraded. In addition, if the thickness is thicker than 5.0 mm, productivity may decrease.

The laminate of the present invention includes a glass substrate, and a polyimide coating film including a filler-containing polyimide layer formed on the glass substrate. Here, the so-called filler The polyimide layer refers to a polyimide layer with a filler content of 5% by mass or more relative to the total mass of the polyimide layer. The so-called filler-free polyimide layer refers to a polyimide layer with a filler content of less than 5% by mass. In the laminate of the present invention, the filler contained in the polyimide layer is a filler having a CTE of 10 ppm/°C or less (hereinafter sometimes referred to as "specific filler") as described in detail below. This can ensure good peelability. In addition, since the CTE of the polyimide film can be sufficiently reduced, curling during peeling can be sufficiently prevented. Even if curling occurs, the radius of curvature of the curling can be sufficiently increased. If the polyimide coating film does not contain a specific filler, the CTE of the polyimide coating film cannot be sufficiently reduced, and therefore curling during peeling cannot be sufficiently prevented. In addition, there are cases where the peelability cannot be ensured.

The polyimide coating film can be composed of only a single polyimide layer containing specific fillers (hereinafter sometimes referred to as "layer-1"), or it can be composed of a polyimide layer that includes this layer-1 and does not contain fillers. The multi-layer structure of the imide layer (hereinafter sometimes referred to as "layer-2") directly connects the layer-1 with the glass substrate. The polyimide layer (layer-1 or layer-2) may also contain well-known additives (for example, lubricants such as silica, alumina, etc.) commonly used in the production of polyimide films.

The so-called polyimide film (polyimide layer) refers to the reaction of tetracarboxylic acids and diamines as raw materials in a solvent at approximately equal moles, and coating on a glass substrate is a polyimide precursor Polyamide acid (hereinafter sometimes abbreviated as "PAA") solution, dried and thermally cured (imidized) to form a polyimide film (polyimide layer). Here, the polyimide obtained from PAA is preferably a non-thermoplastic polyimide, and its glass transition temperature is preferably 250°C or higher.

In the laminate of the present invention, the polyimide film may be a single layer or multiple layers, and it is preferable to use a polyimide obtained by using aromatic tetracarboxylic acids as tetracarboxylic acids 的膜。 The film. Here, examples of tetracarboxylic acids having an aromatic ring (tetracarboxylic acids, dianhydrides or esters thereof, etc.) include pyromellitic acids, 3,3',4,4'-biphenyltetracarboxylic acids, etc. , 2,3,3',4'-biphenyltetracarboxylic acid, 2,2',3,3'-biphenyltetracarboxylic acid, 4,4'-oxydiphthalic acid, 3,3' ,4,4'-diphenyl ketone tetracarboxylic acid, 3,3',4,4'-diphenyl tetracarboxylic acid, p-triphenyl tetracarboxylic acid, m-triphenyl tetracarboxylic acid, etc., and the And other mixtures.

Among them, 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), pyromellitic dianhydride (PMDA), and mixtures of these are preferred.

When the polyimide film has a multilayer structure, the types of aromatic tetracarboxylic acids in the polyimide of layer-1 and layer-2 may be the same or different, and are preferably the same.

In the layered product of the present invention, the polyimide coating film may be a single layer or multiple layers, and it is preferable to use a coating film obtained from a polyimide using an aromatic diamine as a diamine. Examples of aromatic diamines include p-phenylenediamine (PDA), m-phenylenediamine, 4,4'-diaminodiphenyl ether (ODA), 3,4'-diaminodiphenyl ether, 4 ,4'-diaminodiphenyl ether (DADE), 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 2,2 -Bis[4-(4-aminophenoxy)phenyl]propane, 1,2-bis(anilino)ethane, diaminodiphenyl benzene, diaminobenzylaniline, diamino Benzoic acid ester, diaminodiphenyl sulfide, 2,2-bis(p-aminophenyl)propane, 2,2-bis(p-aminophenyl)hexafluoropropane, 1,5-diamino Naphthalene, diaminotoluene, diaminobenzotrifluoride, 1,4-bis(p-aminophenoxy)benzene, 4,4'-bis(p-aminophenoxy)biphenyl, diaminoanthracene Quinone, 4,4'-bis(3-aminophenoxyphenyl)diphenyl sulfide, etc., and mixtures of these. These aromatic diamines can be used in the form of a single component or a mixture.

Among them, PDA, DADE, ODA, and mixtures of these are preferred.

When the polyimide film has a multilayer structure, the type of diamine in the polyimide of layer-1 and layer-2 may be the same or different, and preferably the same.

In the laminate of the present invention, a polyimide film containing a filler with a CTE of 10 ppm/°C or less is used. Such fillers are not particularly limited as long as the CTE is a filler within a specific range. Examples include carbon particles (graphite, carbon black, carbon nanotubes, carbon nanosheets, graphene, etc.), ceramic particles (nitrogen Silicon carbide, silicon carbide, etc.), silicon particles (CTE is 4.7ppm/℃), etc. From the viewpoint of further improving the peelability of the polyimide film and further preventing curling, carbon particles, silicon particles, or a mixture of these are preferred. As long as the CTE of each of these fillers is 10 ppm/°C or less, it does not prevent the inclusion of other atoms as impurities. There is no particular restriction on the lower limit of the CTE of the filler used in the present invention.

For the CTE value of the filler, please refer to RETaylor, CINDAS Data Series on Materials Properties, Thermal Expansion of Solids, Vol 1-4, ASM International, 1998, Welding, Brazil, and Soldering, Vol 6, ASM Handbook, ASM International, 1993 According to the literature value, whether the CTE of the filler is 10ppm/℃ or less can also be judged by the following method. That is, compare a polyimide coating film with no filler with a CTE of 10 to 20 ppm/°C and a polyimide coating film containing 30% by mass of filler relative to the mass of the film in the polyimide coating film. The CTE of the film, if the CTE of the polyimide film with filler is less than the CTE of the polyimide film without filler, then the CTE of the filler is determined to be less than 10 ppm/°C. Conversely, if the CTE of the polyimide film with filler exceeds the CTE of the polyimide film without filler, it is determined that the CTE of the filler exceeds 10 ppm/°C. For example, metal particles such as copper and silver have a CTE exceeding 10 ppm/°C and cannot be used as a filler for the laminate of the present invention.

The average particle size range of the specific filler is preferably set to about 0.01-2 μm. Here, the average particle size refers to the measurement based on the volume measured by the laser diffraction method value. The particle shape of the specific filler is indefinite, spherical, square, linear, etc., and is not limited, and it is preferably an indefinite shape. The content of the specific filler is preferably 5-50% by mass relative to the total mass of the polyimide coating, more preferably 10-40% by mass, and still more preferably 20-30% by mass. By doing so, the CTE of the polyimide film can be further reduced sufficiently, and good peelability can be further ensured. The so-called standard of specific filler content "total mass of polyimide film" refers to when the polyimide film has a single-layer structure "filler-containing polyimide film that constitutes the single-layer structure The total mass of the polyimide layer (layer-1)", when the polyimide film has a multi-layer structure, "the polyimide layer containing the filler that constitutes the polyimide film of the multi-layer structure The total mass of (layer-1)".

As the thickness of the polyimide coating film, when the polyimide coating film has a single-layer structure, it is preferably set to 1 to 50 μm. In addition, when the polyimide film has a multilayer structure including layer-1 and layer-2, the thickness of layer-1 is preferably 0.1 to 5 μm, and more preferably 0.5 to 4 μm. As the thickness of layer-2, it is preferable to set it as about 5-50 micrometers.

[Manufacturing method of laminated body]

The manufacturing method of the laminated body of the present invention is characterized in that the filler-containing polyimide precursor solution is coated on the glass substrate, dried and heat-treated to form a filler-containing polyimide layer (layer-1) . The filler-containing polyimide precursor solution is a polyimide precursor solution for glass substrate laminates containing specific fillers.

In detail, for example, when the polyimide film has a single-layer structure composed of only layer-1, the polyimide film is obtained, for example, by the following method: Even in the solution (hereinafter sometimes referred to as "PAA-S") A PAA solution (hereinafter sometimes referred to as "PAA-F") prepared by mixing specific fillers is coated on a glass substrate and dried, and then the PAA is thermally cured. The solution PAA-F is equivalent to the above-mentioned filler-containing polyimide precursor solution. As a drying temperature after coating, it is preferable to set it as 80-150 degreeC. The thermal curing temperature is preferably 350 to 450°C, more preferably 380 to 420°C. Furthermore, the higher the thermal curing temperature, the lower the CTE of the polyimide film, but the more the adhesion strength between the polyimide film and the glass substrate layer increases, the more the peeling characteristics tend to decrease. If the thermal curing temperature exceeds 450°C, a part of the polyimide film may be thermally decomposed.

In the PAA solution uniformly blended with specific fillers, higher fatty acids such as stearic acid and palmitic acid, as well as release agents such as amides and metal salts can be blended. Among them, stearic acid is preferred. As the compounding amount of the release agent, it is preferable to add 0.01 to 2% by mass, and more preferably 0.1 to 1% by mass relative to the total mass of the polyimide film.

When the specific filler is uniformly blended in PAA-S, it is sufficient to uniformly mix it using known methods such as planetary mixer, sand mill, ball mill, jet mill, three-roll mill, and agitating propeller. Various well-known additives such as surfactants and organosilane coupling agents can also be added to these PAA solutions as needed within a range that does not impair the effects of the present invention. In addition, other polymers other than PAA may be added as needed within a range that does not impair the effects of the present invention.

PAA-S can be obtained by, for example, polymerizing the above-mentioned aromatic tetracarboxylic dianhydride and aromatic diamine in a solvent at approximately equal moles. The solvent is not limited as long as it dissolves PAA. For example, an amide solvent, a urea solvent, an ether solvent, etc. can be used.

烷、1,2-二甲氧基乙烷、二乙二醇二甲醚、二乙二醇二乙醚等。該等溶劑能夠單獨使用或以混合物之形式使用。該等之中，較佳為NMP、DMAc，及該等之混合物。 Specific examples of amide-based solvents include N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), and N,N-dimethylacetamide ( DMAc) and so on. In addition, specific examples of urea-based solvents include tetramethylurea, tetraethylurea, dimethylethylene urea, dimethyl propylene urea, and the like. In addition, as specific examples of ether solvents, 2-methoxyethanol, 2-ethoxyethanol, 2-(methoxymethoxy)ethoxyethanol, 2-isopropoxyethanol, 2 -Butoxyethanol, tetrahydrofuran methanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monoethyl ether, four Ethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, polyethylene glycol , Polypropylene glycol, tetrahydrofuran, two

Alkane, 1,2-Dimethoxyethane, Diethylene Glycol Dimethyl Ether, Diethylene Glycol Diethyl Ether, etc. These solvents can be used alone or in the form of a mixture. Among them, NMP, DMAc, and mixtures of these are preferred.

As the reaction temperature when producing the PAA solution, it is preferably -30 to 70°C, more preferably -15 to 60°C. In addition, in this reaction, the order of addition of the monomers and solvents is not particularly limited, and may be in any order. The solid content concentration of the polyimide precursor is preferably 1-50% by mass, more preferably 5-30% by mass. The PAA can also be partially imidized. Furthermore, these PAA solutions can also use commercially available products.

Also, for example, when the polyimide film has a multilayer structure including layer-1 and layer-2, when the polyimide film is formed on a glass substrate, first, coat the glass plate PAA-F and dry. Next, after coating and drying PAA-S on the coating film (layer-1) to form layer-2, thermal curing is performed together. As the drying temperature after coating, it is preferable that both layer-1 and layer-2 be set to 80 to 150°C. Moreover, as a thermal hardening temperature, 350-450 degreeC is preferable, and 380-420 degreeC is more preferable. Furthermore, after coating layer-1 and drying, it is preferable to coat PAA-S without thermal curing. In this way, the adhesive strength of the interface between layer-1 and layer-2 can be improved, and a polyimide coating film that is strongly integrated can be made.

As a method of applying PAA-F to the glass substrate and coating PAA-S to the PAA-F film, a table coater, dip coater, bar coater, spin coater can be used , Nozzle coater, spray coater and other well-known methods, continuous coating or batch coating.

In the present invention, when the polyimide film has a single-layer structure, another polymer layer may be further formed on layer-1, and when the polyimide film has a multi-layer structure, it may also be layered. -2 is further formed with other polymer layers.

[use]

The laminate of the present invention obtained in the above manner is useful for the manufacture of electronic devices because the polyimide coating film can be easily peeled off from the glass substrate after the electronic components are formed on the surface of the polyimide coating film. Since the polyimide film contains a filler, the adhesive strength with the glass interface becomes weak accordingly, and it can be easily peeled off. In addition, after peeling, the polyimide film on which the electronic component is formed sufficiently prevents curling.

As the electronic component, any electronic component conventionally used in the field of electronic devices can be used. The method of forming the electronic component can be a method known in the field of electronic devices that uses a polyimide film (thin film) as a flexible substrate.

Examples of electronic devices include flat panel displays (FPD) such as liquid crystal displays (LCD), plasma display panels (PDP), and organic EL displays (OLED), and flexible devices such as electronic paper.

[Example]

Hereinafter, the present invention will be described in detail based on examples, but it is not limited by these examples.

<Preparation of polyimide precursor solution PAA-S1~PAA-S2 without filler> (PAA-S1)

In a glass reaction vessel, PDA (0.6 mol) and dehydrated DMAc (polymerization solvent) were put in a nitrogen atmosphere and stirred to dissolve the PDA. While the solution was cooled to below 30°C using a sleeve, BPDA (0.6 mol) was slowly added, and polymerization was carried out at 50°C for 100 minutes, thereby obtaining a polyimide precursor solution PAA-S1. The solid content concentration of PAA-S1 is 15% by mass, and the weight average molecular weight (Mw) converted to polystyrene obtained by GPC is 62,000.

(PAA-S2)

Except that "PDA (0.6 mol)" is set to "a mixture of PDA (0.5 mol) and ODA (0.1 mol)", the polyimide precursor solution PAA-S2 is obtained in the same manner as PAA-S1 . The solid content concentration of PAA-S2 is 16% by mass, and the weight average molecular weight (Mw) in terms of polystyrene obtained by GPC is 72,000.

<Preparation of filler-containing polyimide precursor solution PAA-F2~PAA-F6> [Example 1] (PAA-F2)

Add silicon particles (average particle size: 0.5μm, CTE: 4.7ppm/°C) and dehydrated DMAc (diluted solvent) to PAA-S1. Use a planetary mixer for 60 minutes to mix to obtain a solid content of 16 mass. %. The content of silicon particles relative to the total solid mass (mass of silicon particles + polyimide conversion mass) is 30% by mass of the filler-containing polyimide precursor solution PAA-F2.

(PAA-F3)

PAA-F3 was obtained in the same manner as PAA-F2 except that the content of silicon particles was set to 20% by mass relative to the total solid content.

(PAA-F4)

PAA-F4 was obtained in the same manner as PAA-F2 except that graphite particles (average particle diameter: 0.3 μm, CTE: 0.5 ppm/°C) were used as the filler.

(PAA-F5)

Use carbon black (channel black with an average particle size of 0.03μm, CTE: 0.5ppm/°C) as a filler, and set the carbon black content to 23% by mass relative to the total solid content. Otherwise, it is the same as PAA-F2 The way to obtain PAA-F5.

(PAA-F6)

Add silicon particles (average particle size: 0.5μm, CTE: 4.7ppm/℃), stearic acid, dehydrated DMAc (diluent solvent) to PAA-S2, and use a planetary mixer for 60 minutes of mixing to obtain relative A polyimide precursor solution PAA-F6 containing 30% by mass of silicon particles and 0.5% by mass of stearic acid based on the total solid content (mass of silicon particles + mass of polyimide conversion + stearic acid).

[Comparative Example 1] (PAA-F7)

PAA-F7 was obtained in the same manner as PAA-F2 except that copper particles (average particle diameter: 0.6 μm, CTE: 17 ppm/°C) were used as a filler.

<Manufacturing of single-layer structure laminated body> [Example 2]

On the surface of an alkali-free glass substrate (CTE: 3.2ppm/°C) with a thickness of 0.7mm, coat the filler-containing polyimide precursor solution PAA-F2 by a platform coater and dry it at 130°C for 10 minutes , Thereby forming a PAA film. Next, the temperature was raised from 100°C to 400°C in 2 hours under a nitrogen gas stream, and then heat treatment was performed at 400°C for 2 hours to thermally harden the PAA to be imidized. Thereby, a laminate A-2 including a glass substrate and a polyimide coating film containing a filler with a thickness of about 15 μm was obtained.

(CTE of film)

The polyimide coating film was peeled off from the laminate A-2, and the CTE was measured. As a result, the CTE was 6.3 ppm/°C. Furthermore, the measurement of CTE is carried out by the following method: using TMA-7 manufactured by PerkinElmer, applying a load of 20mN in the length direction of a 13mm×3mm sample, and measuring the heating rate at 10°C/min. The amount of dimensional change between 100°C and 250°C during measurement. Table 1 shows the CTE measurement results of the polyimide film of A-2.

(Peeling characteristics)

The peeling characteristics of the polyimide coating film of the laminate A-2 and the glass substrate interface were evaluated as follows. That is, the adhesive strength of the interface between the polyimide film and the glass substrate was measured by a 180° peel test in accordance with JIS K6854, and when the adhesive strength was less than 0.1 N/cm, the peeling characteristics of the interface were judged to be "good". Conversely, when the adhesive strength is 0.1 N/cm or more, the peeling characteristic is judged to be "bad". Table 1 shows the evaluation results of the peeling characteristics of A-2.

(Curl characteristics)

Next, the curling characteristics of the polyimide film peeled from the laminate were evaluated in the following manner. That is, the radius of curvature of the polyimide coating film peeled from the glass substrate and cut out in a square of 10 cm was measured. In the case where the radius of curvature is 50 mm or more, the curling characteristic is judged to be "good". Conversely, when the radius of curvature is less than 50 mm, the curling characteristic is judged to be "bad". Table 1 shows the evaluation results of the curling characteristics of the polyimide film obtained in A-2.

[Example 3]

Except that PAA-F3 was used as the filler-containing polyimide precursor solution, a laminate A-3 including a filler-containing polyimide film was obtained in the same manner as in Example 2. The CTE, peeling characteristics, and curling characteristics of the film of A-3 were measured or evaluated by the same method as in Example 2, and are shown in Table 1.

[Example 4]

Except that PAA-F4 was used as the filler-containing polyimide precursor solution, a laminate A-4 including a filler-containing polyimide film was obtained in the same manner as in Example 2. The CTE, peeling characteristics, and curling characteristics of the coating film of A-4 were measured or evaluated by the same method as in Example 2 and shown in Table 1.

[Example 5]

Except that PAA-F5 was used as the filler-containing polyimide precursor solution, a laminate including a filler-containing polyimide film was obtained in the same manner as in Example 2. A-5. The CTE, peeling characteristics, and curling characteristics of the film of A-5 were measured or evaluated by the same method as in Example 2 and shown in Table 1.

[Example 6]

On the surface of an alkali-free glass substrate (CTE: 3.2ppm/°C) with a thickness of 0.7mm, PAA-F6 was coated by a platform coater and dried at 130°C for 10 minutes to form a PAA film. Next, it took 2 hours to raise the temperature from 100°C to 380°C under a nitrogen stream, and then heat-treated at 380°C for 2 hours to thermally harden the PAA to be imidized. Thereby, a laminate A-6 including a glass substrate and a polyimide coating film containing a filler with a thickness of about 20 μm was obtained. The CTE, peeling characteristics, and curling characteristics of the film of A-6 were measured or evaluated by the same method as in Example 2 and shown in Table 1.

[Comparative Example 2]

Except for using PAA-S1 as the polyimide precursor solution, a laminate AR-1 including a filler-free polyimide film was obtained in the same manner as in Example 2. The CTE, peeling characteristics, and curling characteristics of the AR-1 film were measured or evaluated by the same method as in Example 2 and shown in Table 1.

[Comparative Example 3]

Except that PAA-S2 was used as the filler-containing polyimide precursor solution, a laminate AR-2 including a filler-containing polyimide film was obtained in the same manner as in Example 2. The CTE, peeling characteristics, and curling characteristics of the AR-2 film were measured or evaluated by the same method as in Example 2 and shown in Table 1.

[Comparative Example 4]

Except for using PAA-F7 as the filler-containing polyimide precursor solution, a laminate AR-7 including a filler-containing polyimide film was obtained in the same manner as in Example 2. The CTE, peeling characteristics, and curling characteristics of the AR-7 film were measured or evaluated by the same method as in Example 2 and shown in Table 1.

As shown in Table 1, the laminates A-2 to A-6 of the present invention contain a specific filler in the layer in contact with the glass substrate. Therefore, it can be seen that the peeling characteristics of the polyimide film are good, the CTE is low, and the curling characteristics are also good.

On the other hand, it can be seen that since the polyimide film of AR-7 shown in Comparative Example 4 contains a filler, the peeling characteristics are good, but because the CTE of the copper particles as the filler is high, the curling characteristics are poor.

In addition, as shown in Comparative Examples 2 and 3, it can be seen that if it is a polyimide coating film that does not contain a filler, both the peeling characteristic and the curling characteristic are inferior.

<Manufacturing of Multilayer Structure Type Laminated Body> [Example 7]

Coat PAA-F2 on the surface of the above-mentioned alkali-free glass substrate by a platform coater, It was dried at 130°C for 10 minutes to form a PAA film. Next, return to room temperature (25°C), apply PAA-S1 on the PAA film with a platform coater, and dry at 130°C for 10 minutes to form a second layer of PAA film. Next, the temperature was raised from 100°C to 400°C in 2 hours under a nitrogen gas stream, and then heat treatment was performed at 400°C for 2 hours to thermally harden the PAA to be imidized. Thereby, a glass substrate, and layer-1 (polyimide layer containing filler: thickness 3μm) and layer-2 (polyimide layer without filler: thickness 20μm) are formed in sequence on the glass substrate. ) The obtained laminate L-2 of polyimide film (thickness: 23 μm). The peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

[Example 8]

Except that PAA-F3 was used for the formation of layer-1, a glass substrate was obtained in the same manner as in Example 7, and layer-1 was sequentially formed on the glass substrate (filler-containing polyimide layer: thickness 3μm ) A laminate L-3 of a polyimide film (thickness: 24 μm) obtained by layer-2 (polyimide layer without filler: thickness 21 μm). The peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

[Example 9]

Except that PAA-F4 was used for the formation of layer-1, a glass substrate was obtained in the same manner as in Example 7, and layer-1 was sequentially formed on the glass substrate (filler-containing polyimide layer: thickness 2μm ) A laminated body L-4 of a polyimide film (thickness: 22 μm) obtained by layer-2 (polyimide layer without filler: thickness 20 μm). The peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

[Example 10]

Except that PAA-F5 was used for the formation of layer-1, the same method as in Example 7 was used to obtain a glass substrate and a layer-1 (filler-containing polyimide layer: thickness 2μm) on the glass substrate. ) A laminate L-5 of a polyimide film (thickness: 23 μm) obtained by layer-2 (polyimide layer without filler: thickness 21 μm). The peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

[Example 11]

Except that PAA-F6 was used for the formation of layer-1, a glass substrate was obtained in the same manner as in Example 7, and layer-1 was sequentially formed on the glass substrate (filler-containing polyimide layer: thickness 2μm ) A laminated body L-6 of a polyimide film (thickness: 23 μm) obtained by layer-2 (polyimide layer without filler: thickness 21 μm). The peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

[Comparative Example 5]

Except that PAA-S1 without filler was used as the formation of layer-1, a glass substrate was obtained in the same manner as in Example 7, and layer-1 (polyamide without filler) was sequentially formed on the glass substrate. Amine layer: thickness of 3μm) and layer-2 (polyimide layer without filler: thickness of 20μm) obtained polyimide film (thickness: 23μm) laminated body LR-1. The peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

[Comparative Example 6]

Except that PAA-F7 was used for the formation of layer-1, the same as in Example 7 The method includes the glass substrate, and the layer-1 (polyimide layer containing filler: thickness 3μm) and layer-2 (polyimide layer without filler: thickness 20μm) are sequentially formed on the glass substrate. After the polyimide-coated laminate LR-7 (thickness: 23 μm), the peeling characteristics and curling characteristics were evaluated by the same method as in Example 2 and shown in Table 2.

As shown in Table 2, the laminates L-2 to L-6 of the present invention contain a specific filler in the layer-1 in contact with the glass substrate. Therefore, it can be seen that the peeling characteristics are good, the CTE of layer-1 is low, and the curling characteristics are also good.

On the other hand, it can be seen that since layer-1 of LR-7 shown in Comparative Example 6 contains a filler, the peeling characteristics are good, but since the CTE of the copper particles as the filler is high, the curling characteristics are poor.

In addition, according to Comparative Example 5, it can be seen that if a polyimide film containing no filler is used as the layer-1, even if the polyimide film is multilayered, both peeling characteristics and curling characteristics are inferior.

(Industrial availability)

Since the laminate of the present invention has good peelability and the peeled polyimide film is not easy to curl, it can be used for the manufacture of electronic devices by forming electronic components on the surface of the polyimide film constituting the laminate .

Claims (5)

A laminated body comprising an alkali-free glass substrate and a polyimide film including a filler-containing polyimide layer formed on the glass substrate, characterized in that the filler is carbon particles and/or Silicon particles, and the filler content is 10-40% by mass relative to the total mass of the polyimide film. The laminate of claim 1, wherein the polyimide coating film includes the polyimide layer containing the filler, and the polyimide containing no filler formed on the polyimide layer containing the filler Floor. A method for manufacturing a laminated body is the method for manufacturing a laminated body according to claim 1 or 2, characterized in that by coating a polyimide precursor solution containing a filler on an alkali-free glass substrate, drying and heat treatment, A polyimide layer containing filler is formed. A method of using a laminate, which is characterized in that the laminate of claim 1 or 2 is used for the manufacture of electronic devices. A polyimide precursor solution for laminating alkali-free glass substrates is characterized in that it contains carbon particles and/or silicon particles as fillers, and the filler content is 10-40% by mass relative to the total solid content.