TWI656024B - Heat resistant resin film, manufacturing method thereof, heating furnace, image display device and method of manufacturing same - Google Patents

Abstract

The present invention provides a heat-resistant resin film whose outgas generated during heating at 450 ° C. for 30 minutes under a helium gas flow is 0.01 μg / cm ² to 4 μg / cm ² . Furthermore, the present invention provides a method for manufacturing a heat-resistant resin film, which includes a step of applying a solution containing a precursor of a heat-resistant resin on a support, and a step of heating in multiple stages. The manufacturing method is characterized in that the step of heating in multiple stages includes at least the following steps in sequence: (A) the first heating step, under an atmosphere with an oxygen concentration of 10 vol% or more, at a temperature higher than 200 ° C Heating; and (B) a second heating step, heating at a temperature higher than the first heating step in an atmosphere having an oxygen concentration of 3% by volume or less.

Description

Heat-resistant resin film, manufacturing method thereof, heating furnace and image display device And its manufacturing method

The present invention relates to a method for manufacturing a heat-resistant resin film, a heating furnace, and an image display device.

Heat-resistant resins such as polyimide, polybenzoxazole, polybenzothiazole, and polybenzimidazole are used in various fields represented by semiconductor applications due to their excellent electrical insulation, heat resistance, and mechanical properties . Recently, it is also widely used in substrates of image display devices such as organic electroluminescence (EL) displays, electronic paper, color filters, etc., and can manufacture image display devices with strong impact resistance and flexibility.

When a heat-resistant resin is used as a substrate of an image display device, gas permeability such as oxygen or water vapor is high, and therefore, a gas barrier film such as a silicon nitride film is generally stacked and used. Various researches have been conducted on the film formation method of the gas barrier film, and most of them use a vacuum process such as Plasma Enhanced Chemical Vapor Deposition (PECVD). Therefore, it is preferably out gas from the heat-resistant resin Very little, so that the film formation in the vacuum process will not become bad.

Most heat-resistant resins are usually solvent-insoluble and thermally infusible, and it is difficult to directly perform molding processing. Therefore, when forming a heat-resistant resin film, the following operations are generally performed: a solution containing a precursor of a heat-resistant resin (hereinafter referred to as a varnish) is applied to a support and heated, thereby transforming into a heat-resistant resin film . For example, in the case of polyimide, a polyimide film can be obtained by applying a solution containing polyamic acid as a precursor on a support and heating it at a temperature of 180 ° C to 600 ° C. The heating method may be heating in one stage or heating in multiple stages. For example, Patent Document 1 reports a method of heating in multiple stages.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2000-248077

In order to improve the mechanical properties of the heat-resistant resin film, it is often effective to increase the heating temperature within a range that does not exceed the thermal decomposition temperature of the heat-resistant resin. However, if the heating temperature is increased in the atmosphere, the oxygen molecules in the atmosphere will cause the resin to oxidize or decompose due to it, so it is difficult to obtain good mechanical properties. Therefore, it is generally recommended to perform heating in an inert gas atmosphere such as nitrogen or argon or in a vacuum atmosphere.

However, if heated under an inert atmosphere, the outgassing component is likely to remain in the heat-resistant resin film, and it is difficult to reduce outgassing of the heat-resistant resin film. In addition, with Compared with heating in the atmosphere, heating in an inert atmosphere has a problem of cost (power, gas). Furthermore, it takes time to replace the heating atmosphere from the atmosphere with an inert gas or vacuum before heating, and there is also a problem that the productivity of the heat-resistant resin film decreases.

The problem of the present invention is to solve the aforementioned problems. That is, an object of the present invention is to provide a heat-resistant resin film with little outgassing and high mechanical characteristics. In addition, an object of the present invention is to provide a method for manufacturing a heat-resistant resin film that does not impair the mechanical properties of the heat-resistant resin film and reduces outgassing even if the step of heating in an inert atmosphere is shortened.

One of the features of the present invention is a heat-resistant resin film whose outgas generated during heating at 450 ° C. for 30 minutes under a helium gas flow is 0.01 μg / cm ² to 4 μg / cm ² .

In addition, one of the features of the present invention is a method for manufacturing a heat-resistant resin film, which includes a step of applying a solution containing a precursor of a heat-resistant resin on a support, and a step of heating in multiple stages, and the The method for manufacturing a heat-resistant resin film is characterized in that the step of heating in multiple stages includes at least the following steps in sequence: (A) the first heating step, under an atmosphere having an oxygen concentration of 10 vol% or more, Heating at a temperature higher than 200 ° C; and (B) a second heating step, heating at a temperature higher than the first heating step in an atmosphere with an oxygen concentration of 3 vol% or less.

Furthermore, one of the characteristics of the present invention is a heating furnace provided with: measuring A temperature measuring unit for temperature in the furnace, a temperature adjusting unit for adjusting the temperature in the furnace, an oxygen concentration measuring unit for measuring the oxygen concentration in the furnace, and a gas flow rate adjustment for adjusting the flow rate of the heating atmosphere gas into the furnace And a control unit that controls the temperature adjustment unit and the gas flow adjustment unit, and the control unit controls the gas flow adjustment unit according to the oxygen concentration in the furnace measured by the oxygen concentration measurement unit , And after the oxygen concentration reaches a predetermined oxygen concentration, the temperature adjustment unit is controlled so that the temperature in the furnace measured by the temperature measurement unit reaches a predetermined temperature.

According to the present invention, it is possible to provide a heat-resistant resin film with little outgassing and high mechanical characteristics.

10‧‧‧Heating furnace

11‧‧‧ Furnace

12‧‧‧ furnace

21‧‧‧Temperature Adjustment Department

22‧‧‧Temperature Measurement Department

23‧‧‧Heating Department

31‧‧‧Oxygen concentration meter

32‧‧‧Gas intake

41, 51‧‧‧ gas supply pipe

42、52‧‧‧ On-off valve for flushing

43、53‧‧‧Flushing flow regulating valve

44, 54‧‧‧ On-off valve for operation

45、55‧‧‧Flow regulating valve for operation

61‧‧‧Exhaust pipe

62‧‧‧Exhaust switch valve

63‧‧‧Exhaust flow adjustment valve

71‧‧‧Control Department

81‧‧‧User interface

FIG. 1 is a schematic diagram of the heating furnace 1.

<Heat-resistant resin film>

One of the features of the present invention is a heat-resistant resin film whose outgas generated during heating at 450 ° C. for 30 minutes under a helium gas flow is 0.01 μg / cm ² to 4 μg / cm ² . Here, the so-called outgas generated during heating at 450 ° C. for 30 minutes under a helium gas flow can be obtained by measurement using the following equipment and conditions.

Measuring device: heating unit "Small-4" (manufactured by Toray Research Center Co., Ltd.), gas chromatography / mass spectrometer (Gas Chromatograph / Mass Spectrometer, GC / MS) "QP5050A (7)" (island (Made by Tsu Manufacturing Co., Ltd.)

Heating condition: increase the temperature from room temperature at 10 ℃ / min, keep it for 30 minutes after reaching 450 ℃

Measurement atmosphere: under helium flow (50mL / min).

For the heat-resistant resin film of the present invention, the outgas measured during the period of 30 minutes after reaching 450 ° C by the method must be 0.01 μg / cm ² to 4 μg / cm ² . If it is 4 μg / cm ² or less, it is less likely to cause film formation defects in vacuum processes such as plasma chemical vapor growth (PECVD). It is more preferably 2 μg / cm ² or less, and still more preferably 1 μg / cm ² or less.

On the other hand, when the heat-resistant resin film formed on the glass substrate is peeled from the glass substrate using laser, the outgas generated by the heat-resistant resin film stays at the interface with the glass, thereby peeling off Made easy. Therefore, the outgas of the heat-resistant resin film must be 0.01 μg / cm ² or more. More preferably 0.02μg / cm ² or more, and further is excellent 0.04μg / cm ² or more.

Furthermore, the heat-resistant resin film of the present invention preferably has a maximum tensile stress of 200 MPa or more. Here, the so-called maximum tensile stress can be obtained by measuring in accordance with Japanese Industrial Standards (JIS K 7127: 1999) using the following equipment and conditions.

Measuring device: Tensilon universal material testing machine "RTM-100" (made by Orientec Co., Ltd.)

Determination of sample shape: ribbon

Measuring sample size: length> 70mm, width 10mm

Stretching speed: 50mm / min

Distance between chucks at the start of the test: 50mm

Experimental temperature: 0 ℃ ~ 35 ℃

Number of samples: 10

Calculation method of measurement results: arithmetic mean of measured values of 10 samples

If the maximum tensile stress is 200 MPa or more, it has suitable mechanical properties as a substrate for an image display device such as an organic EL display, electronic paper, color filter, or the like. More preferably, it is 250 MPa or more. In addition, it is preferably 800 MPa or less, and more preferably 600 MPa or less. If it is 800 MPa or less, it has flexibility as a flexible substrate.

<Heat-resistant resin>

The heat-resistant resin in the present invention refers to a resin that does not have a melting point or decomposition temperature below 300 ° C, and includes polyimide, polybenzoxazole, polybenzothiazole, polybenzimidazole, polyamide, polyimide Ether ballast, polyether ether ketone, etc. Among them, the heat-resistant resin that can be preferably used in the present invention is polyimide, polybenzoxazole, polybenzimidazole, polybenzothiazole, and more preferably polyimide. If the heat-resistant resin is polyimide, when manufacturing an image display device using a heat-resistant resin film, it can have heat resistance (emission characteristics, glass transition temperature, etc.) to the temperature of the manufacturing process, and is suitable for The manufactured image display device imparts tough mechanical properties.

Polyimide is a resin having a structure represented by chemical formula (1).

[Chem 1]

In the chemical formula (1), X represents a tetravalent tetracarboxylic acid residue having 2 or more carbon atoms, and Y represents a divalent diamine residue having 2 or more carbon atoms. m represents a positive integer.

X is preferably a tetravalent hydrocarbon group having 2 to 80 carbon atoms. In addition, X may be a tetravalent organic group having 2 to 80 carbon atoms, which contains hydrogen and carbon as essential components and contains one or more atoms selected from boron, oxygen, sulfur, nitrogen, phosphorus, silicon, and halogen. Each atom of boron, oxygen, sulfur, nitrogen, phosphorus, silicon, and halogen is preferably independently in the range of 20 or less, more preferably in the range of 10 or less.

Examples of the tetracarboxylic acid forming X include the following compounds. Examples of the aromatic tetracarboxylic acid include monocyclic aromatic tetracarboxylic acid compounds, such as pyromellitic acid, 2,3,5,6-pyridinetetracarboxylic acid, and the like; various isomers of biphenyltetracarboxylic acid, such as 3 , 3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3', 4'-biphenyltetracarboxylic acid, 2,2 ', 3,3'-biphenyltetracarboxylic acid, 3,3 ', 4,4'-benzophenone tetracarboxylic acid, 2,2', 3,3'-benzophenone tetracarboxylic acid, etc .; bis (dicarboxyphenyl) compounds, such as 2,2-bis ( 3,4-dicarboxyphenyl) hexafluoropropane, 2,2-bis (2,3-dicarboxyphenyl) hexafluoropropane, 2,2-bis (3,4-dicarboxyphenyl) propane, 2 , 2-bis (2,3-dicarboxyphenyl) propane, 1,1-bis (3,4-dicarboxyphenyl) ethane, 1,1-bis (2,3-dicarboxyphenyl) ethane Alkanes, bis (3,4-dicarboxyphenyl) methane, bis (2,3-di Carboxyphenyl) methane, bis (3,4-dicarboxyphenyl) ash, bis (3,4-dicarboxyphenyl) ether, etc .; bis (dicarboxyphenoxyphenyl) compounds, such as 2,2- Bis [4- (3,4-dicarboxyphenoxy) phenyl] hexafluoropropane, 2,2-bis [4- (2,3-dicarboxyphenoxy) phenyl] hexafluoropropane, 2, 2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane, 2,2-bis [4- (2,3-dicarboxyphenoxy) phenyl] propane, 2,2- Bis [4- (3,4-dicarboxyphenoxy) phenyl] ash, 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] ether, etc .; naphthalene or condensed polycyclic Various isomers of aromatic tetracarboxylic acids, such as 1,2,5,6-naphthalene tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid, 2,3,6,7-naphthalene tetracarboxylic acid , 3,4,9,10-perylenetetracarboxylic acid, etc .; bis (trimellitic acid monoester anhydride) compounds, such as p-phenylene bis (trimellitic acid monoester anhydride), p-biphenylene bis ( Trimellitic acid monoester anhydride), ethylidene bis (trimellitic acid monoester anhydride), bisphenol A bis (trimellitic acid monoester anhydride), etc.

Examples of the aliphatic tetracarboxylic acid include chain aliphatic tetracarboxylic acid compounds, such as butane tetracarboxylic acid, and alicyclic tetracarboxylic acid compounds, such as cyclobutane tetracarboxylic acid, 1,2,3,4-ring. Pentane tetracarboxylic acid, 1,2,4,5-cyclohexane tetracarboxylic acid, bicyclic [2.2.1.] Heptane tetracarboxylic acid, bicyclic [3.3.1.] Tetracarboxylic acid, bicyclic [3.1.1 .] Hept-2-ene tetracarboxylic acid, bicyclo [2.2.2.] Octane tetracarboxylic acid, adamantane tetracarboxylic acid, etc.

These tetracarboxylic acids can be used directly, or they can be used in the state of acid anhydride, active ester, and active amide. In addition, two or more of these tetracarboxylic acids may be used.

For applications requiring heat resistance, it is preferable to use an aromatic tetracarboxylic acid in an amount of 50 mol% (mol%) or more of the entire tetracarboxylic acid. Among them, it is preferable that X is a tetravalent tetracarboxylic acid residue represented by chemical formula (2) or formula (3) as a main component.

That is, it is preferable to use pyromellitic acid or 3,3 ', 4,4'-biphenyltetracarboxylic acid as the main component. The main component in the present invention means that 50 mol% or more of the total tetracarboxylic acid is used. It is more preferable to use 80 mol% or more. If it is a polyamic acid obtained from these tetracarboxylic acids, there is little deterioration even if it is heated in the atmosphere. Therefore, in the method for producing a heat-resistant resin film which is one of the features of the present invention, even if it is further performed at a temperature higher than 300 ° C (A) in an atmosphere having an oxygen concentration of 10 vol% or more, higher than 200 ° C The first heating step of heating at the same temperature is no problem.

In addition, by using silicon-containing tetracarboxylic acids such as dimethylsilane diphthalic acid, 1,3-bis (phthalic acid) tetramethyldisiloxane, the adhesion to the support can be improved or Resistance to oxygen plasma and ultraviolet (Ultraviolet, UV) ozone treatment used for cleaning. These silicon-containing tetracarboxylic acids are preferably used at 1 mol% to 30 mol% of the total tetracarboxylic acid.

For the tetracarboxylic acid exemplified above, a part of the hydrogen contained in the residue of the tetracarboxylic acid may also be substituted with the following groups: a hydrocarbon group having a carbon number of 1 to 10 such as methyl and ethyl, trifluoromethyl, etc. Fluoroalkyl with 1 to 10 carbons, F, Cl, Br, I and other groups. Furthermore, if it is substituted with acidic groups such as OH, COOH, SO ₃ H, CONH ₂ , and SO ₂ NH ₂ , the solubility of the resin in the alkaline aqueous solution is improved. Therefore, when used as a photosensitive resin composition described later, good.

Y is preferably a divalent hydrocarbon group having 2 to 80 carbon atoms. In addition, Y may be a divalent organic group having 2 to 80 carbon atoms, which contains hydrogen and carbon as essential components and contains one or more atoms selected from boron, oxygen, sulfur, nitrogen, phosphorus, silicon, and halogen. Each atom of boron, oxygen, sulfur, nitrogen, phosphorus, silicon, and halogen is preferably independently in the range of 20 or less, more preferably in the range of 10 or less.

Examples of Y-forming diamines include the following compounds. Examples of the diamine compound containing an aromatic ring include: monocyclic aromatic diamine compounds, such as m-phenylenediamine, p-phenylenediamine, 3,5-diaminobenzoic acid, etc .; naphthalene or condensed polycyclic aromatic diamine Compounds such as 1,5-naphthalene diamine, 2,6-naphthalene diamine, 9,10-anthracene diamine, 2,7-diamino stilbene, etc .; bis (diaminophenyl) compounds or these compounds Various derivatives, such as 4,4'-diaminobenzylanilide, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3-carboxy-4 , 4'-diaminodiphenyl ether, 3-sulfonic acid-4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 4,4'-diamine Diphenylmethane, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4 ' -Diaminodiphenyl sulfide, 4-aminobenzoic acid 4-aminophenyl ester, 9,9-bis (4-aminophenyl) stilbene, 1,3-bis (4-anilino) Tetramethyldisilaxane, etc .; 4,4'-diaminobiphenyl or its various derivatives, such as 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4 ' -Diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl -4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diaminobiphenyl, 2,2 ', 3,3'-tetramethyl-4,4 '-Diaminobiphenyl, 3,3', 4,4'-tetramethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) -4,4 ' -Diaminobiphenyl, etc .; bis (aminophenoxy) compounds, such as bis (4-aminophenoxyphenyl) satin, bis (3-aminophenoxyphenyl) satin, bis (4 -Aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (3-amino Phenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, etc .; bis (3-amino-4-hydroxyphenyl) compounds such as bis (3-amino-4-hydroxybenzene) Group) Hexafluoropropane, bis (3-amino-4-hydroxyphenyl) ash, bis (3-amino-4-hydroxyphenyl) propane, bis (3-amino-4-hydroxyphenyl) methane , Bis (3-amino-4-hydroxyphenyl) ether, bis (3-amino-4-hydroxy) biphenyl, 9,9-bis (3-amino-4-hydroxyphenyl) stilbene, etc .; Bis (aminobenzyl) compounds, such as 2,2'-bis [N- (3-aminobenzyl) -3-amino-4-hydroxyphenyl] hexafluoropropane, 2,2 '-Double [N- (4 -Aminobenzyl) -3-amino-4-hydroxyphenyl] hexafluoropropane, 2,2'-bis [N- (3-aminobenzyl) -3-amino-4 -Hydroxyphenyl] propane, 2,2'-bis [N- (4-aminobenzyl) -3-amino-4-hydroxyphenyl] propane, bis [N- (3-aminobenzene (Methyl) -3-amino-4-hydroxyphenyl] lanthanum, bis [N- (4-aminobenzyl) -3-amino-4-hydroxyphenyl] lanthanum, 9,9- Bis [N- (3-aminobenzyl) -3-amino-4-hydroxyphenyl] stilbene, 9,9-bis [N- (4-aminobenzyl) -3-amine 4-hydroxyphenyl) stilbene, N, N'-bis (3-aminobenzyl) -2,5-diamino-1,4-dihydroxybenzene, N, N'-bis ( (4-aminobenzyl) -2,5-diamino-1,4-dihydroxybenzene, N, N'-bis (3-aminobenzyl) -4,4'-diamine -3,3-dihydroxybiphenyl, N, N'-bis (4-aminobenzene (Formyl) -4,4'-diamino-3,3-dihydroxybiphenyl, N, N'-bis (3-aminobenzyl) -3,3'-diamino-4 , 4-dihydroxybiphenyl, N, N'-bis (4-aminobenzyl) -3,3'-diamino-4,4-dihydroxybiphenyl, etc .; heterocyclic diamines Compounds such as 2- (4-aminophenyl) -5-aminobenzoxazole, 2- (3-aminophenyl) -5-aminobenzoxazole, 2- (4-amino Phenyl) -6-aminobenzoxazole, 2- (3-aminophenyl) -6-aminobenzoxazole, 1,4-bis (5-amino-2-benzoxazole Group) benzene, 1,4-bis (6-amino-2-benzoxazolyl) benzene, 1,3-bis (5-amino-2-benzoxazolyl) benzene, 1,3- Bis (6-amino-2-benzoxazolyl) benzene, 2,6-bis (4-aminophenyl) benzobisoxazole, 2,6-bis (3-aminophenyl) benzene Bisbisoxazole, 2,2'-bis [(3-aminophenyl) -5-benzoxazolyl] hexafluoropropane, 2,2'-bis [(4-aminophenyl) -5 -Benzoxazolyl] hexafluoropropane, bis [(3-aminophenyl) -5-benzoxazolyl], bis [(4-aminophenyl) -5-benzoxazolyl] , Bis [(3-aminophenyl) -6-benzoxazolyl], bis [(4-aminophenyl) -6-benzoxazolyl], etc .; or these diamine compounds Part of hydrogen bonded to the aromatic ring By halogen-substituted hydrocarbon compound or the like.

The aliphatic diamine compound can be exemplified by linear diamine compounds, such as ethylenediamine, propylenediamine, butanediamine, pentanediamine, hexamethylenediamine, octanediamine, nonanediamine, decanediamine, eleven Alkanediamine, dodecanediamine, tetramethylhexamethylenediamine, 1,12- (4,9-dioxa) dodecanediamine, 1,8- (3,6-dioxa) octane Diamine, 1,3-bis (3-aminopropyl) tetramethyldisilaxane, etc .; alicyclic diamine compounds such as cyclohexanediamine, 4,4'-methylenebis (cyclohexyl) Amine), isophorone diamine, etc .; Known as Jeffamine (trade name, manufactured by Huntsman Corporation), polyoxyethylene amine, polyoxypropylene amine, copolymerized compounds thereof, and the like are known.

These diamines can be used directly or in the form of corresponding trimethylsilylated diamines. In addition, two or more of these diamines may be used.

For applications requiring heat resistance, it is preferable to use an aromatic diamine compound of 50 mol% or more of the entire diamine compound. Among them, Y is preferably a divalent diamine residue represented by the chemical formula (4) as a main component.

That is, it is preferable to use p-phenylenediamine as the main component. The main component in the present invention means that 50 mol% or more of the entire diamine compound is used. It is more preferable to use 80 mol% or more. If it is a polyamic acid obtained by using p-phenylenediamine, even if it is heated in the atmosphere, there is little deterioration. Therefore, in the method for producing a heat-resistant resin film which is one of the features of the present invention, even if it is further performed at a temperature higher than 300 ° C (A) in an atmosphere having an oxygen concentration of 10 vol% or more, higher than 200 ° C The first heating step of heating at the same temperature is no problem.

It is particularly preferred that X in the chemical formula (1) is a tetravalent tetracarboxylic acid residue represented by the chemical formula (2) or (3) as a main component, and Y is represented by the chemical formula (4) The represented divalent diamine residue serves as the main component. The polyamic acid introduced into the polyimide of such a structure deteriorates particularly little even when heated in the atmosphere. Therefore, in the method for producing a heat-resistant resin film which is one of the features of the present invention, even if it is further performed at a temperature higher than 300 ° C (A) in an atmosphere having an oxygen concentration of 10 vol% or more, higher than 200 ° C By performing the first heating step of heating at a temperature of 50 ° C, the maximum tensile stress of the resulting heat-resistant resin film can also be ensured to be high.

In addition, by using silicon-containing diamines such as 1,3-bis (3-aminopropyl) tetramethyldisilaxane, 1,3-bis (4-anilino) tetramethyldisilaxane As a diamine component, the adhesion to the support, the resistance to the oxygen plasma used for washing, and the UV ozone treatment can be improved. These silicon-containing diamine compounds are preferably used at 1 mol% to 30 mol% of the total diamine compound.

For the diamine compounds exemplified above, a part of the hydrogen contained in the diamine compound may also be substituted with the following groups: a hydrocarbon group having a carbon number of 1 to 10 such as methyl and ethyl, and a carbon number of 1 such as trifluoromethyl ~ 10 fluoroalkyl, F, Cl, Br, I and other groups. Furthermore, if it is substituted with an acidic group such as OH, COOH, SO ₃ H, CONH ₂ , and SO ₂ NH ₂ , the solubility of the resin in the alkaline aqueous solution is improved. Therefore, when used as a photosensitive resin composition as described later good.

The weight-average molecular weight of the precursor of the heat-resistant resin of the present invention is preferably adjusted using gel permeation chromatography in terms of polystyrene to preferably 100,000 or less, more preferably 80,000 or less, and still more preferably 50,000 or less . Within this range, even if it is a high-concentration varnish, the increase in viscosity can be further suppressed. In addition, the weight average molecular weight is preferably 2000 or more, more preferably 3000 or more, and further preferably 5000 or more. If the weight-average molecular weight is 2,000 or more, the viscosity of the varnish will not be too low, and better coatability can be ensured.

In the chemical formula (1), m represents the number of repeating polyimide units, as long as it is within a range that satisfies the weight average molecular weight of the heat-resistant resin of the present invention. m is preferably 5 or more, and more preferably 10 or more. In addition, it is preferably 500 or less, and more preferably 200 or less.

The precursor of the heat-resistant resin of the present invention can be used in the form of varnish by further dissolving in a solvent. By applying this varnish to various supports as described later, a film containing a precursor of a heat-resistant resin can be formed. By converting the precursor of the heat-resistant resin contained in the film into a heat-resistant resin, a heat-resistant resin film can be manufactured. Regarding the solvent, the following solvents can be used alone or in combination of two or more: N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylformamide, N, N-dimethyl Aprotic polar solvents such as ethyl acetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol Alcohol ethyl methyl ether, diethylene glycol dimethyl ether and other ethers, acetone, methyl ethyl ketone, diisobutyl ketone, diacetone alcohol, cyclohexanone and other ketones, ethyl acetate, propylene glycol monomethyl Esters such as ether acetate and ethyl lactate, aromatic hydrocarbons such as toluene and xylene, etc.

The preferable content of the solvent is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, and preferably 2000 parts by mass or less, and more preferably 1500 parts by mass or less with respect to 100 parts by mass of the precursor of the heat resistant resin. If the range satisfies this condition, the viscosity is suitable for coating, and the film thickness after coating can be easily adjusted.

The solution containing the precursor of the heat-resistant resin of the present invention is preferably at least Any one of (a) a photoacid generator, (b) a phenolic hydroxyl group-containing compound, and (c) a surfactant.

The varnish of the present invention can be made into a photosensitive resin composition by further containing (a) a photoacid generator. By containing a photoacid generator, an acid is generated in the light irradiated portion and the solubility of the light irradiated portion in the alkaline aqueous solution is increased, and a positive concave-convex pattern in which the light irradiated portion is dissolved can be obtained. In addition, by containing a photoacid generator and an epoxy compound or a thermal crosslinking agent described later, the acid generated in the light irradiated part promotes the crosslinking reaction of the epoxy compound or the thermal crosslinking agent, and the insoluble light irradiated part Negative bump pattern.

Examples of the photoacid generator include quinonediazide compounds, osmium salts, phosphonium salts, diazonium salts, and phosphonium salts. Two or more of these photo-acid generators may be contained to obtain a photosensitive resin composition with high sensitivity.

Examples of the quinonediazide compounds include quinonediazide sulfonic acids bonded to polyhydroxy compounds in the form of esters, and quinonediazide sulfonic acids formed from sulfonamide bonds with polyamine compounds, The quinonediazide sulfonic acid and polyhydroxypolyamine compound form an ester bond and / or a sulfonamide bond, etc. Preferably, more than 50 mol% of the total functional groups of these polyhydroxy compounds or polyamino compounds are substituted with quinonediazides.

In the present invention, as the quinonediazide, any of 5-naphthoquinonediazidesulfonyl and 4-naphthoquinonediazidesulfonyl can be preferably used. The 4-naphthoquinone diazide sulfonyl ester compound has absorption in the i-ray range of the mercury lamp and is suitable for i-ray exposure. The absorption of the 5-naphthoquinone diazide sulfonyl ester compound extends to the g-ray range of the mercury lamp and is suitable for g-ray exposure. In the present invention, it is preferable to select 4-naphthoquinone diazide sulfonyl ester compound and 5-naphthoquinone diazide sulfonyl ester compound according to the wavelength of exposure. Alternatively, Naphthoquinone diazide sulfonyl ester compounds containing 4-naphthoquinone diazide sulfonyl group and 5-naphthoquinone diazide sulfonyl group in the same molecule, or 4- in the same resin composition Naphthoquinone diazide sulfonyl ester compound and 5-naphthoquinone diazide sulfonyl ester compound.

Among the photoacid generators, the osmium salt, the phosphonium salt, and the diazonium salt appropriately stabilize the acid component generated by the exposure, which is preferable. Among them, sam salt is preferred. It may further contain a sensitizer etc. as needed.

In the present invention, from the viewpoint of increasing sensitivity, the content of the photoacid generator is preferably 0.01 to 50 parts by mass relative to 100 parts by mass of the precursor of the heat-resistant resin. Among them, the quinonediazide compound is preferably 3 parts by mass to 40 parts by mass. In addition, the total amount of osmium salt, phosphonium salt, and diazonium salt is preferably 0.5 to 20 parts by mass.

The photosensitive resin composition of the present invention may contain a thermal crosslinking agent represented by the following chemical formula (31) or a thermal crosslinking agent containing the structure represented by the following chemical formula (32) (hereinafter collectively referred to as thermal crosslinking) Agent). These thermal cross-linking agents can cross-link the heat-resistant resin or its precursor, and other added components, and improve the chemical resistance and hardness of the heat-resistant resin film obtained.

In the chemical formula (31), R ³¹ represents a divalent to tetravalent linking group. R ³² represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, Cl, Br, I or F. R ³³ and R ³⁴ independently represent CH ₂ OR ³⁶ (R ³⁶ is hydrogen or a monovalent hydrocarbon group having 1 to 6 carbon atoms). R ³⁵ represents hydrogen, methyl or ethyl. s represents an integer from 0 to 2, and t represents an integer from 2 to 4. The plurality of R ³² may be the same or different. The plurality of R ³³ and R ³⁴ may be the same or different. The plurality of R ³⁵ may be the same or different. An example of the linking group R ³¹ is shown below.

In the chemical formula, R ⁴¹ to R ⁶⁰ represent hydrogen, a monovalent hydrocarbon group having 1 to 20 carbon atoms, or a hydrocarbon group in which a part of hydrogen of these hydrocarbon groups is substituted with Cl, Br, I, or F.

[化 6] ＊ -N (CH ₂ OR ³⁷ ) _u (H) _v (32)

In the chemical formula (32), R ³⁷ represents hydrogen or a monovalent hydrocarbon group having 1 to 6 carbon atoms. u means 1 or 2, v means 0 or 1. Where u + v is 1 or 2.

In the chemical formula (31), R ³³ and R ³⁴ represent CH ₂ OR ³⁶ as a thermally crosslinkable group. In view of the fact that the thermal crosslinking agent of the chemical formula (31) has appropriate reactivity and excellent storage stability, R ^{36 is} preferably a monovalent hydrocarbon group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group. base.

Preferred examples of the thermal crosslinking agent containing the structure represented by the chemical formula (31) are shown below.

In the chemical formula (32), R ^{37 is} preferably a monovalent hydrocarbon group having 1 to 4 carbon atoms. In addition, from the viewpoint of the stability of the compound or the storage stability of the photosensitive resin composition, R ^{37 is} preferably a methyl group or an ethyl group, and the number of (CH ₂ OR ³⁷ ) groups contained in the compound is preferably 8 or less.

Preferred examples of the thermal crosslinking agent containing the group represented by the chemical formula (32) are shown below.

The content of the thermal crosslinking agent is preferably 10 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the precursor of the heat-resistant resin. When the content of the thermal crosslinking agent is 10 parts by mass or more and 100 parts by mass or less, the strength of the heat-resistant resin film obtained is high, and the storage stability of the photosensitive resin composition is also excellent.

The varnish of the present invention may further contain a thermal acid generator. The thermal acid generator generates acid by heating after development described later, and promotes the precursor and heat of the heat-resistant resin In addition to the cross-linking reaction of the cross-linking agent, the hardening reaction of the precursor of the heat-resistant resin is promoted. Therefore, the chemical resistance of the resulting heat-resistant resin film is improved, and the film thickness can be reduced. The acid generated by the thermal acid generator is preferably a strong acid, for example, preferably arylsulfonic acids such as p-toluenesulfonic acid and benzenesulfonic acid, alkylsulfonic acids such as methanesulfonic acid, ethanesulfonic acid, and butanesulfonic acid. In the present invention, the thermal acid generator is preferably an aliphatic sulfonic acid compound represented by chemical formula (33) or formula (34), and may contain two or more of these compounds.

In the chemical formulas (33) and (34), R ⁶¹ to R ⁶³ may be the same or different, and represent an organic group having 1 to 20 carbon atoms, preferably a hydrocarbon group having 1 to 20 carbon atoms. In addition, it may be an organic group having 1 to 20 carbon atoms, which contains hydrogen and carbon as essential components and contains one or more atoms selected from boron, oxygen, sulfur, nitrogen, phosphorus, silicon, and halogen.

Specific examples of the compound represented by the chemical formula (33) include the following compounds.

[化 10]

Specific examples of the compound represented by the chemical formula (34) include the following compounds.

From the viewpoint of further promoting the crosslinking reaction, the content of the thermal acid generator is preferably 0.5 parts by mass or more and preferably 10 parts by mass or less with respect to 100 parts by mass of the precursor of the heat-resistant resin.

If necessary, in order to compensate for the alkali developability of the photosensitive resin composition, (b) a phenolic hydroxyl group-containing compound may be contained. Examples of the phenolic hydroxyl group-containing compound include compounds of the following trade names (Bis-Z, BisOC-Z, BisOPP-Z, BisP-CP, Bis26X-Z, BisOTBP-Z, BisOCHP- manufactured by Honshu Chemical Industry Co., Ltd.) Z, BisOCR-CP, BisP-MZ, BisP-EZ, Bis26X-CP, BisP-PZ, BisP-IPZ, BisCR-IPZ, BisOCP-IPZ, BisOIPP-CP, Bis26X-IPZ, BisOTBP-CP, TekP-4HBPA (Tetrakis P-DO-BPA), TrisP-HAP, TrisP-PA, TrisP-PHBA, TrisP-SA, TrisOCR- PA, BisOFP-Z, BisRS-2P, BisPG-26X, BisRS-3P, BisOC-OCHP, BisPC-OCHP, Bis25X-OCHP, Bis26X-OCHP, BisOCHP-OC, Bis236T-OCHP, methylene tris-FR-CR, BisRS -26X, BisRS-OCHP), Asahi Organic Materials Co., Ltd. (BIR-OC, BIP-PC, BIR-PC, BIR-PTBP, BIR-PCHP, BIP-BIOC-F, 4PC) , BIR-BIPC-F, TEP-BIP-A), 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,3- Dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,4-dihydroxyquinoline, 2,6-dihydroxyquinoline, 2,3-dihydroxyquinoxaline, anthracene- 1,2,10-triol, anthracene-1,8,9-triol, 8-hydroxyquinoline, etc. By containing these phenolic hydroxyl group-containing compounds, the resulting photosensitive resin composition hardly dissolves in the alkali developer before exposure, and if exposed, it is easily dissolved in the alkali developer, so the film due to development Less thinning and easy development in a short time. Therefore, the sensitivity is easily improved.

The content of such a phenolic hydroxyl group-containing compound is preferably 3 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the precursor of the heat-resistant resin.

The varnish of the present invention may contain an adhesion improver. Examples of the adhesion modifier include vinyl trimethoxy silane, vinyl triethoxy silane, epoxycyclohexyl ethyl trimethoxy silane, 3-glycidoxy propyl trimethoxy silane, 3-glycidoxy Propylpropyltriethoxysilane, p-styryltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-amino Propyl tri Silane coupling agent such as methoxysilane, titanium chelating agent, aluminum chelating agent, etc. In addition to these adhesion modifiers, alkoxysilane-containing aromatic amine compounds, alkoxysilane-containing aromatic amide compounds and the like as shown below may be mentioned.

In addition, a compound obtained by reacting an aromatic amine compound and an alkoxy-containing silicon compound can also be used. Examples of such compounds include compounds obtained by reacting an aromatic amine compound with an alkoxysilane compound containing a group that reacts with an amine group, such as an epoxy group and a chloromethyl group. Two or more of the adhesion modifiers listed above may be contained. By containing these adhesion modifiers, it can improve the base substrates such as silicon wafers, indium tin oxide (ITO), SiO ₂ , silicon nitride, etc. when developing photosensitive resin films, etc. Of tightness. In addition, by improving the adhesion between the heat-resistant resin film and the base substrate, the resistance to oxygen plasma or UV ozone treatment used for cleaning and the like can also be improved. The content of the adhesion modifier is preferably 0.01 to 10 parts by mass relative to 100 parts by mass of the precursor of the heat-resistant resin.

The varnish of the present invention may contain inorganic particles to improve heat resistance. Examples of the inorganic particles used for this purpose include metal inorganic particles of platinum, gold, palladium, silver, copper, nickel, zinc, aluminum, iron, cobalt, rhodium, ruthenium, tin, lead, bismuth, tungsten, etc., or silicon oxide (silica), metal oxide inorganic particles such as titanium oxide, aluminum oxide, zinc oxide, tin oxide, tungsten oxide, zirconium oxide, calcium carbonate, barium sulfate, etc. The shape of the inorganic particles is not particularly limited, and examples thereof include spherical, elliptical, flat, rod-shaped, and fibrous shapes. In addition, in order to suppress an increase in the surface roughness of the heat-resistant resin film containing inorganic particles, the average particle diameter of the inorganic particles is preferably 1 nm or more and 100 nm or less, more preferably 1 nm or more and 50 nm or less, and still more preferably 1 nm or more and 30 nm the following.

The content of the inorganic particles is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, further preferably 10 parts by mass or more, and preferably 100 parts by mass or less with respect to 100 parts by mass of the precursor of the heat-resistant resin. It is preferably 80 parts by mass or less, and more preferably 50 parts by mass or less. If the content of the inorganic particles is 3 parts by mass or more, the heat resistance is sufficiently improved, and if it is 100 parts by mass or less, the toughness of the calcined film is unlikely to decrease.

The varnish of the present invention preferably contains (c) a surfactant to improve coatability. The surfactant can be exemplified by "Fluorad" manufactured by Sumitomo 3M Co., Ltd. (Registered trademark), `` Megafac '' (registered trademark) made by DIC (shares), `` Sulflon '' (registered trademark) made by Asahi Glass (shares) and other fluorine-based interfaces Active agents, KP341 manufactured by Shin-Etsu Chemical Co., Ltd., DBE manufactured by Chisso Co., Ltd., "Polyflow" (registered trademark) manufactured by Kyoeisha Chemical Co., Ltd., and Gera "Glanol" (registered trademark), BYK and other organic silicone surfactants manufactured by BYK Chemie (shares), Polyplastics (produced by Kyoeisha Chemical Co., Ltd.) Polyflow) and other acrylic polymer surfactants. The surfactant preferably contains 0.01 to 10 parts by mass relative to 100 parts by mass of the precursor of the heat-resistant resin.

Generally, (a) a photoacid generator, (b) a phenolic hydroxyl group-containing compound, and (c) a surfactant remain in a small amount after heating as described later, thereby easily causing outgassing. However, according to the method for producing a heat-resistant resin film of the present invention, even when a solution containing a precursor of a heat-resistant resin contains a surfactant, a heat-resistant resin with little outgassing and excellent mechanical properties can be obtained membrane.

The precursor of the heat-resistant resin can be polymerized by a known method. For example, in the case of polyimide which can be preferably used in the present invention, tetracarboxylic acid or the corresponding acid dianhydride, active ester, active polyamide, etc. can be used as the acid component, and diamine or the corresponding trimethylamine The silylated diamine and the like are used as diamine components, and these components are polymerized in a reaction solvent, thereby obtaining a polyamic acid as a precursor. In addition, the polyamic acid may be a carboxyl group esterified by a hydrocarbon group having 1 to 10 carbon atoms or an alkyl silane group having 1 to 10 carbon atoms.

Regarding the reaction solvent, the following solvents can be used alone or in two or more types: N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylformamide, N, N-di Aprotic polar solvents such as methyl acetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether diethylene glycol Alcohol ethyl methyl ether, diethylene glycol dimethyl ether and other ethers, acetone, methyl ethyl ketone, diisobutyl ketone, diacetone alcohol, cyclohexanone and other ketones, ethyl acetate, propylene glycol monomethyl Esters such as ether acetate and ethyl lactate, aromatic hydrocarbons such as toluene and xylene, etc. Furthermore, by using the same solvent as the solvent used for the varnish, the target varnish can be produced without separating the resin after the production.

Next, a method of manufacturing a solution (hereinafter referred to as varnish) containing the precursor of the heat-resistant resin film of the present invention will be described. For example, a varnish can be obtained by dissolving a precursor of a heat-resistant resin, a photoacid generator, a dissolution regulator, an adhesion modifier, an inorganic particle, a surfactant, or the like in a solvent. The dissolution method may be stirring or heating. When a photoacid generator is included, the heating temperature is preferably set within a range that does not impair the performance as a photosensitive resin composition, and is usually room temperature to 80 ° C. In addition, the dissolution order of each component is not particularly limited. For example, there is a method of sequentially dissolving a compound having low solubility. In addition, components such as a surfactant or a part of the adhesion improver that are likely to generate bubbles during stirring and dissolution can be added last after dissolving other components to prevent poor dissolution of other components due to the generation of bubbles.

The obtained varnish is preferably filtered using a filter to remove foreign matters such as waste. The filter pore size is, for example, 10 μm, 3 μm, 1 μm, 0.5 μm, 0.2 μm, 0.1 μm, 0.07 μm, 0.05 μm, etc., but it is not limited to these values. Regarding the filter material, there are polypropylene (PP), polyethylene (PE), nylon (NY), and polytetrafluoroethylene (PTFE), etc., preferably polyethylene or nylon.

<Manufacturing method of heat-resistant resin film>

Next, the method of manufacturing the heat-resistant resin film of the present invention will be described. The method for producing a heat-resistant resin film as one of the features of the present invention includes a step of applying a solution containing a precursor of a heat-resistant resin on a support, and a step of heating in multiple stages, and the heat-resistant resin film The manufacturing method is characterized in that the step of heating in multiple stages includes at least the following steps in sequence: (A) the first heating step, under an atmosphere with an oxygen concentration of 10 vol% or more, at a temperature higher than 200 ° C Heating; and (B) the second heating step, heating at a temperature higher than the first heating step in an atmosphere having an oxygen concentration of 3 vol% or less.

First, the varnish containing the precursor of the heat-resistant resin is applied to the support. Examples of the support include wafer substrates such as silicon and gallium arsenide, glass substrates such as sapphire glass, soda lime glass, and alkali-free glass, metal substrates such as stainless steel and copper, metal foils, and ceramic substrates, but are not limited to these supports. body.

The coating method of the varnish may include a spin coating method, a slit coating method, a dip coating method, a spray coating method, a printing method, etc., and these methods may be combined. It is also possible to pre-treat the support with the adhesion modifier described above before coating. For example, the following method may be used: dissolving the adhesion modifier at 0.5% by mass to 20% by mass in isopropyl alcohol, ethanol, methanol, water, tetrahydrofuran, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethyl lactate, The solution in a solvent such as diethyl adipate is treated by spin coating, slot die coating, bar coating, dip coating, spray coating, steam treatment, etc. on the surface of the support. Decompression drying can be carried out if necessary After the treatment, the support and the adhesion modifier are reacted by heating at 50 ° C to 300 ° C.

After coating, the coating film of the varnish is usually dried. The drying method may use reduced-pressure drying or heating drying, or a combination of these methods. The method of drying under reduced pressure is performed, for example, by placing a support formed with a coating film in a vacuum chamber and depressurizing the vacuum chamber. In addition, the heating and drying is performed by using a heating plate, an oven, or the like, and processing using infrared rays, hot air, or the like. In the case of using a hot plate, the coating film is directly held on the plate, or the coating film is held on a fixture such as a proximity pin provided on the plate, and heated and dried.

The materials of the proximity pins include metal materials such as aluminum or stainless steel, or synthetic resins such as polyimide resin or "Teflon" (registered trademark). As long as they have heat resistance, any material of proximity pins can be used. The height of the adjacent pin can be selected according to the size of the support, the type of solvent used for the varnish, the drying method, etc., and is preferably about 0.1 mm to 10 mm. The heating temperature varies depending on the type or purpose of the solvent used in the varnish, and it is preferably heated in the range of room temperature to 180 ° C for 1 minute to several hours.

When the photoacid generator is contained in the varnish of the present invention, a pattern can be formed from the dried coating film by the method described below. Actinic rays are irradiated on the coating film through a mask having a desired pattern, and exposure is performed. Actinic rays used for exposure include ultraviolet rays, visible rays, electron beams, X-rays, etc. In the present invention, i-rays (365 nm), h-rays (405 nm), and g-rays (436 nm) using mercury lamps are preferred. In the case of positive photosensitivity, the exposed portion is dissolved in the developer. In the case of negative photosensitivity, the exposed portion is hardened and insoluble in the developer.

After exposure, the developer is used to remove the exposed portion in the case of the positive type and the non-exposed portion in the case of the negative type, thereby forming a desired pattern. The developer is preferably tetramethylammonium, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, both in the positive type and the negative type. Diethylamine, methylamine, dimethylamine, dimethylaminoethyl acetate, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, hexamethylene An aqueous solution of a compound that shows basicity such as diamine. In addition, depending on the situation, one or more of the following compounds may be added to these alkaline aqueous solutions: N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N- Polar solvents such as dimethylacetamide, dimethylsulfoxide, γ-butyrolactone, dimethylacrylamide, methanol, ethanol, isopropanol and other alcohols, ethyl lactate, propylene glycol monomethyl ether acetate Esters such as esters, ketones such as cyclopentanone, cyclohexanone, isobutyl ketone, methyl isobutyl ketone, etc.

In addition, in the case of a negative type, the polar solvent, alcohols, esters, ketones, etc. that do not contain an alkaline aqueous solution may be used alone or in combination. After development, it is usually rinsed with water. Here, alcohols such as ethanol and isopropanol, and esters such as ethyl lactate and propylene glycol monomethyl ether acetate may be added to the water for rinsing treatment.

Then, multi-stage heating, which is a feature of the method for producing a heat-resistant resin film of the present invention, is performed. In the step of performing this multi-stage heating, heating is performed in the range of 180 ° C. or higher to form the coating film into a heat-resistant resin film. The heating step of the present invention The step must be heated in multiple stages and must include at least the following steps in sequence: (A) the first heating step, heating at a temperature above 200 ° C in an atmosphere with an oxygen concentration of 10 vol% or more; and (B) In the second heating step, heating is performed at a temperature higher than that in the first heating step in an atmosphere having an oxygen concentration of 3% vol or less. The reason is explained below.

When the varnish of the present invention contains a component other than the precursor of the heat-resistant resin and a solvent or when there is an unreacted monomer component, the component or its decomposition product may remain in the heat-resistant resin film to make the heat resistant The outgassing characteristics of the resin film are reduced. Unlike thermal crosslinking agents or adhesion modifiers, photoacid generators and phenolic hydroxyl-containing compounds do not have a binding point with heat-resistant resins or substrates, so they easily cause outgassing. In addition, as described above, surfactants are often resins such as acrylic polymers and polyoxyethyl alkyl ethers. These compounds are decomposed in the heat-resistant resin film to leave oligomer components or monomer components, causing the outgassing characteristics of the heat-resistant resin film to be lowered. Therefore, it is preferable to perform heating in an atmosphere in which oxygen molecules are present in the first heating step, thereby oxidizing components that cause outgassing to promote decomposition or gasification.

The range of the oxygen concentration in the first heating step is 10 vol% or more, and more preferably 15 vol% or more. If the range of oxygen concentration is 10 vol% or more, the components that cause outgassing can be oxidized by the oxidation reaction to promote decomposition and gasification. In addition, the range of the oxygen concentration in the first heating step is preferably 22 vol% or less. If the range of the oxygen concentration is 22 vol% or less, the first heating step can be performed in the atmosphere, so it is basically unnecessary to introduce oxygen into the heating atmosphere.

The heating temperature in the first step must be to harden the precursor of the heat-resistant resin Above the necessary temperature. Specifically, it must be a temperature higher than 200 ° C. In addition, the heating temperature in the first heating step is preferably lower than the temperature at which the heat-resistant resin is oxidized. Specifically, it is preferably 420 ° C or lower, more preferably 370 ° C or lower, and still more preferably 320 ° C or lower.

On the other hand, in order to improve the mechanical properties of the heat-resistant resin film, it is preferable to increase the heating temperature. However, if the heating temperature is increased in an atmosphere in which oxygen molecules are present, the heat-resistant resin is oxidized or decomposed thereby, and it is difficult to obtain good physical properties. Therefore, by heating in an atmosphere with a low oxygen concentration in the second heating step, the oxidation or decomposition of the heat-resistant resin can be suppressed and the mechanical properties can be improved.

The range of the oxygen concentration in the second heating step is 3 vol% or less, more preferably 1 vol% or less, and further preferably 0.1 vol% or less. If the range of the oxygen concentration is 3 vol% or less, even if the heating temperature in the second step is 300 ° C. or higher, the deterioration of the resin can be prevented. In addition, the range of the oxygen concentration in the second heating step is preferably 0.000001vol% or more, more preferably 0.00001vol% or more, and still more preferably 0.0001vol% or more. If the oxygen concentration is in the range of 0.000001vol% or more, it is possible to prevent the use amount of inert gas from increasing extremely or putting a burden on the vacuum pump.

The heating temperature in the second step must be a temperature higher than the highest temperature in the first heating step, specifically, it is preferably 300 ° C. or higher, more preferably 350 ° C. or higher, and still more preferably 400 ° C. or higher. On the other hand, the heating temperature in the second heating step is preferably not higher than the decomposition temperature of the resin, specifically, it is preferably 600 ° C. or lower, and more preferably 550 ° C. or lower.

In the method for producing a heat-resistant resin film of the present invention, the step of heating in multiple stages may include three or more heating steps. In the first heating step In the case where the additional heating step is provided before, it is preferable to perform heating at a temperature lower than that of the first heating step in an atmosphere having an oxygen concentration higher than that of the first heating step. When an additional step is provided after the second heating step, it is preferable to perform heating at a temperature higher than that of the second heating step in an atmosphere with an oxygen concentration equal to or lower than that of the second heating step.

The heating method may also preferably use any method described in the heating and drying described above. That is, it is preferable to use a device such as a hot plate or an oven, and perform treatment with hot air, infrared rays, or the like.

After all the heating steps are completed, cooling is performed, and the heat-resistant resin film is taken out from the device. The cooling can be exemplified by a method of stopping the heating of the device and performing cooling caused by natural standing cooling, or forced cooling by a cooling section provided in the device. When it is taken out by hand after cooling, it is preferably cooled to room temperature, and when it is not limited to this, it can be taken out at a temperature higher than room temperature. Among them, it is preferably performed within a range where the physical properties of the heat-resistant resin film are not greatly reduced. In addition, the atmosphere in the device during cooling is preferably maintained in the state immediately after the heating step, and may be replaced with the atmosphere at the time when the temperature in the device is cooled to a predetermined temperature or lower. In this case, it is also preferable to determine the temperature to be replaced with the atmosphere within a range where the physical properties of the heat-resistant resin film are not greatly reduced.

<Heating furnace>

Furthermore, a heating furnace which is one of the characteristics of the present invention will be described. The heating furnace includes a temperature measuring unit that measures the temperature in the furnace, A temperature adjustment unit that adjusts the temperature in the furnace, an oxygen concentration measurement unit that measures the oxygen concentration in the furnace, a gas flow adjustment unit that adjusts the flow rate of the heating atmosphere gas into the furnace, and controls the temperature adjustment unit And a control unit of a gas flow adjustment unit, and the heating furnace is characterized in that the control unit controls the gas flow adjustment unit according to the oxygen concentration in the furnace measured by the oxygen concentration measurement unit, After the oxygen concentration reaches a predetermined oxygen concentration, the temperature adjustment unit is controlled so that the temperature in the furnace measured by the temperature measurement unit reaches a predetermined temperature.

An embodiment of the heating furnace of the present invention will be described using drawings. FIG. 1 is a schematic diagram of a heating furnace 10 as an embodiment of heating according to the present invention.

A gas supply pipe 41, a gas supply pipe 51, and an exhaust pipe 61 are connected to the furnace body 11 for prearranging the object to be heated. The gas supply pipe 41 and the gas supply pipe 51 are provided with gas flow adjustment sections, which are respectively composed of a flushing on-off valve 42 and a flushing on-off valve 52, a flushing flow adjustment valve 43 and a flushing flow adjustment valve 53, and a switch The valve 44 and the on-off valve 54 for operation, the flow adjustment valve 45 for operation, and the flow adjustment valve 55 for operation are comprised. The exhaust pipe 61 is also provided with an exhaust switching valve 62 and an exhaust flow adjustment valve 63.

The flushing on-off valve is particularly opened when the atmosphere of the furnace 12 filled with a gas different from the supply gas is rapidly replaced by the supply gas. Therefore, must It is necessary to set a sufficiently large gas flow rate by the flow adjustment valve for flushing so that the inside of the furnace 12 can be replaced by the supply gas. On the other hand, the on-off valve for operation is opened especially when gas is supplied to maintain the atmosphere in the furnace 12. Therefore, it is sufficient to set the gas flow rate that can maintain only the atmosphere in the furnace 12 by operating the flow adjustment valve, and generally, a gas flow rate that is less than the flow rate set by the flushing flow adjustment valve is set.

The furnace body 11 is provided with a temperature measuring part 22 and a heating part 23. The temperature measurement unit 22 and the heating unit 23 are connected to the temperature adjustment unit 21 via electrical connections shown by broken lines. Furthermore, the temperature adjustment unit 21 is electrically connected to the control unit 71.

In addition, the heating furnace 10 is provided with an oxygen concentration measuring section for measuring the oxygen concentration, and is composed of an oxygen concentration meter 31 and a gas sampling port 32 for sampling the gas in the furnace 12. The oxygen concentration meter 31 is also connected to the control unit 71 via an electrical connection shown by a broken line. Furthermore, in order to automatically execute the heating step under a predetermined condition, a user interface 81 with a preset program is provided, which is also electrically connected to the control unit 71.

In addition, although not shown in the figure, the gas flow adjustment section is also electrically connected to the control section 71. The switching of the on-off valve 42, on-off valve 44, on-off valve 52, on-off valve 54 and on-off valve 62 is caused by The electrical signal from the control unit 71 is controlled. In addition, although not shown in the figure, the furnace body 11 is provided with a switch window for taking out / into the object to be heated.

The control unit 71 controls at least the temperature adjustment unit 21 and the gas flow adjustment unit. Specifically, the gas flow rate adjustment unit is controlled according to the oxygen concentration in the furnace 12 measured by the oxygen concentration measurement unit, and the oxygen concentration in the furnace 12 reaches the predetermined oxygen concentration After that, the temperature adjustment unit 21 is controlled so that the temperature of the furnace 12 measured by the temperature measurement unit becomes a predetermined temperature.

At this time, the control unit 71 preferably controls the temperature adjustment unit 21 and the gas flow adjustment unit to continuously perform a multi-step heating step. For example, a multi-stage including at least a first heating step of heating at a first temperature in a first oxygen concentration atmosphere and a second heating step of heating at a second temperature in a second oxygen concentration atmosphere In the heating step, it is preferable that the control part 71 can control the gas flow rate adjustment part and the temperature adjustment part 21 to continuously perform the first heating step and the second heating step.

Hereinafter, the case where the heat-resistant resin film of the present invention is manufactured using the heating furnace 10 will be described, and the operation of each part will also be described. As an example, it is set to perform a two-step heating step, and is set to perform the first heating step and the second heating step under the atmosphere (oxygen concentration 21 vol%) and nitrogen (oxygen concentration 0.01 vol% or less), respectively.

First, the gas supply pipe 41 and the gas supply pipe 51 are connected to supply lines of nitrogen and atmosphere, respectively. Then, the solution of the precursor containing the heat-resistant resin film described above is applied to the substrate and dried, and the resulting coating film is placed in the furnace body 11. The program of the heating step is set via the user interface 81.

After the above preparations are completed, the heating step begins. At the beginning, the furnace 12 is filled with the atmosphere, so the first heating step is started. When the furnace 12 is not at the same oxygen concentration as the atmosphere, the oxygen concentration meter 31 detects it, and the control unit 71 sends a signal to the flushing on-off valve 52 to open the valve and flush the atmosphere into the furnace 12. If the furnace 12 is filled with air and the oxygen concentration meter 31 detects this situation, the control The signal of the section 71 closes the valve of the flushing on-off valve 52 and stops the supply of the atmosphere. In the first heating step, both the on-off valve 42 for flushing and the on-off valve 44 for operation provided on the gas supply pipe 41 for supplying nitrogen gas are closed.

In the state where the furnace 12 is filled with the atmosphere, the signal is sent from the control part 71 to the temperature adjustment part 21, and the temperature rise is started according to a preset program. During the heating process, the temperature measuring unit 22 constantly monitors the temperature of the furnace 12 in such a manner that the heating can be performed according to the program, and the temperature adjusting unit 21 controls the heating unit 23. In the first heating step, outgassing occurs from the coating film, so it is preferable to supply the atmosphere from the gas supply pipe 51 for supplying the atmosphere to the furnace 12 all the time. The exhaust pipe 61 is discharged. Therefore, during heating, it is preferable that the on-off valve 54 for operation of the gas supply pipe 51 is opened.

In addition, it is more preferable to adjust the operation flow rate adjustment valve 55 and the exhaust flow rate adjustment valve 63 so that the atmosphere in the furnace 12 always becomes a positive pressure. When the inside of the furnace 12 is under negative pressure, outside air may enter the inside of the furnace 12 through the gap between the opening and closing windows.

In the first heating step, the oxygen concentration in the furnace 12 can be constantly monitored by the oxygen concentration meter 31. When it is detected that the oxygen concentration has decreased, the control unit 71 sends a signal to the gas flow adjustment unit, and opens the flushing on-off valve 52 to flush the atmosphere. When the oxygen concentration in the furnace 12 returns to a predetermined concentration and the oxygen concentration meter 31 can detect this, the control unit 71 sends a signal to the gas flow adjustment unit, closes the flushing on-off valve 52, and stops flushing of the atmosphere.

During the period when the flushing on-off valve 52 is opened to flush the atmosphere, the The on-off valve 54 can also be closed. However, at the time when the flushing on-off valve 52 is closed and the flushing of the atmosphere is stopped, it is preferable to open the on-off valve 54 for operation and set the state to continue supplying the atmosphere.

After completing the first heating step and before starting the second heating step, in order to reduce the oxygen concentration in the furnace 12 to a predetermined concentration, a signal is sent from the control unit 71 to the gas flow adjustment unit. With this signal, both the flushing on-off valve 52 and the operation on-off valve 54 of the gas supply pipe 51 are closed, and the supply of the atmosphere is stopped. On the other hand, the flushing on-off valve 42 of the gas supply pipe 41 is opened to supply nitrogen gas into the furnace 12. Nitrogen supply continues until the furnace 12 reaches a predetermined oxygen concentration or less, and the start of the second heating step is temporarily in a standby state.

If the oxygen concentration meter 31 detects that the oxygen concentration in the furnace 12 has reached a predetermined oxygen concentration or less, the signal is sent to the control unit 71, and the control unit 71 closes the flushing on-off valve 42 of the gas supply pipe 41. At the same time, the self-control unit 71 sends a signal to start the second heating step to the temperature adjustment unit 21 to start heating.

Since the second heating step also generates outgassing from the coating film during heating, it is preferable to supply nitrogen gas from the gas supply pipe 41 to the furnace 12 all the time, and to exhaust the outgassing from the coating film together with the atmosphere in the furnace 12 The trachea 61 is discharged. Therefore, during heating, it is preferable that the operation on-off valve 44 of the gas supply pipe 41 is opened. In addition, it is more preferable to adjust the operation flow rate adjustment valve 45 and the exhaust flow rate adjustment valve 63 so that the atmosphere in the furnace 12 always becomes positive pressure. When the inside of the furnace 12 is under negative pressure, outside air may enter the inside of the furnace 12 through the gap between the opening and closing windows.

In the second heating step, it is also set to be monitored continuously by the oxygen concentration meter 31 It depends on the oxygen concentration of 12 in the furnace. In the case where an increase in oxygen concentration is detected, the structure is such that the control unit 71 sends a signal to the gas flow adjustment unit, and the flushing on-off valve 42 is opened to flush nitrogen gas. When the oxygen concentration in the furnace 12 reaches a predetermined concentration or less and the oxygen concentration meter 31 detects this, the self-control unit 71 sends a signal to the gas flow adjustment unit, and closes the flushing on-off valve 42 to stop flushing with nitrogen.

After the second heating step is completed, the cooling of the furnace 12 is started. When the signal from the control unit 71 is sent to the temperature adjustment unit 21 and the heating of the heating unit 23 is stopped accordingly, natural cooling is started. Depending on the situation, the furnace body 11 may be a heating furnace provided with a cooling unit (not shown) electrically connected to the temperature adjustment unit 21. By the operation of the cooling section, the temperature in the furnace 12 can be forcibly lowered.

When the temperature in the furnace 12 drops below a predetermined temperature, the operation of replacing the atmosphere in the furnace 12 with the atmosphere is started. This operation is performed as follows, for example. The temperature measurement unit 22 detects that the temperature of the furnace 12 has reached a predetermined temperature or less in accordance with the program set by the user interface 81. The signal is sent to the control unit 71 via the temperature adjustment unit 21. Then, the control unit 71 sends a signal to the gas flow adjustment unit, closes the flushing on-off valve 42 and the operation on-off valve 44 provided in the gas supply pipe 41, and stops the supply of nitrogen gas into the furnace 12. At the same time, the flushing on-off valve 52 provided in the gas supply pipe 51 is opened, and the supply of the atmosphere into the furnace 12 is started.

During cooling, the temperature and oxygen concentration in the furnace 12 are also monitored by the temperature measuring part 22 and the oxygen concentration meter 31, and the temperature in the furnace 12 is reduced to below the predetermined temperature set by the program, and the atmosphere of the furnace 12 becomes At the moment when the oxygen concentration is approximately the same as the atmosphere, all steps are completed. Then, take it from the switch window provided on the furnace body 11 出 涂膜。 Out of the coating. In the heating step, the switch window is preferably in a locked state, and is preferably configured as follows: the lock is released at the time when all steps are completed, so that the heated body can be taken out.

The above description shows an example of a heating furnace that is one of the characteristics of the present invention, but the present invention is not limited to this example. In the above example, the following structure is adopted: the gas flow adjustment section is controlled by the control section 71, and automatically performs the on-off valve 42, the on-off valve 44, the on-off valve 52, and the switch according to a program set in advance through the user interface 81 The valve 54 and the switching valve 62 are opened and closed. The flow rate adjustment valve 43, the flow rate adjustment valve 45, the flow rate adjustment valve 53, the flow rate adjustment valve 55, and the flow rate adjustment valve 63 may be adjusted in advance and set to be unchanged in the heating step, or may be automatically adjusted.

In addition, in order to monitor the oxygen concentration during heating, the oxygen concentration meter 31 must always be operated. However, it may be difficult to measure the accurate oxygen concentration due to outgassing from the heated body, or the oxygen concentration meter 31 may be contaminated. To prevent this, it is preferable to provide a cold trap between the gas sampling port 32 and the oxygen concentration meter 31. By installing a cold trap, it becomes possible to capture the outgas from the heated body and measure the accurate oxygen concentration. In addition, the possibility of contamination of the oxygen concentration meter 31 also becomes small.

The heat-resistant resin film obtained by the present invention can be preferably used for the surface protection film or interlayer insulating film of a semiconductor element, the insulating layer or spacer layer of an organic electroluminescence element (organic EL element), and the flatness of a thin film transistor substrate Chemical film, insulating layer of organic transistor, flexible printed circuit board, flexible display substrate, flexible electronic paper substrate, flexible solar cell substrate, flexible color filter substrate, etc. Especially for image display devices such as organic EL, electronic paper, color filters, etc. In other words, since the heat-resistant resin film has heat resistance (emission characteristics, glass transition temperature, etc.) to the temperature of its manufacturing process and mechanical characteristics suitable for imparting toughness to the image display device after manufacture, it can be preferably used As a substrate for these devices.

A method of using the heat-resistant resin film obtained by the manufacturing method of the present invention as a substrate of an image display device will be described. First, a heat-resistant resin film is manufactured on a support such as a glass substrate by the manufacturing method of the present invention.

Then, a pixel driving element or a colored pixel is formed on the heat-resistant resin film. For example, in the case of an organic EL display, a thin film transistor (TFT) as an image driving element, a first electrode, an organic EL light-emitting element, a second electrode, and a sealing film are sequentially formed. In the case of a color filter, after forming a black matrix as needed, coloring pixels such as red, green, and blue are formed.

If necessary, a gas barrier film may be provided between the heat-resistant resin film and the pixel driving element or the colored pixel. By providing the gas barrier film, it is possible to prevent moisture or oxygen from penetrating the heat-resistant resin film from the outside of the image display device and causing deterioration of the pixel driving element or the colored pixels. As the gas barrier film, a single film of an inorganic film such as a silicon oxide film (SiOx), a silicon nitride film (SiNy), a silicon oxynitride film (SiOxNy), or a film formed by stacking a variety of inorganic films can be used. Regarding the film forming methods of these gas barrier films, the film formation may be performed using methods such as chemical vapor growth (Chemical Vapor Deposition, CVD) or physical vapor growth (Physical Vapor Deposition, PVD). Furthermore, as the gas barrier film, a film formed by alternately laminating these inorganic films with an organic film such as polyvinyl alcohol may be used.

Finally, peeling is performed at the interface between the support and the heat-resistant resin film to obtain an image display device containing the heat-resistant resin film. About the support body and heat resistance tree The method of peeling at the interface of the lipid film includes a method using laser, a method of mechanical peeling, a method of etching the support, and the like. In the method using laser, a support such as a glass substrate is irradiated with laser light from the side where the image display element is not formed, whereby peeling can be performed without damaging the image display element. In addition, a primer layer for easy peeling may be provided between the support and the heat-resistant resin film.

[Example]

The present invention will be described below with examples and the like, but the present invention is not limited by these examples. In addition, when the number of measurements is not specifically mentioned, only one measurement is performed.

(1) Measurement of maximum tensile elongation and maximum tensile stress

The heat-resistant resin film-laminated glass substrates obtained in Examples and Comparative Examples were immersed in hydrofluoric acid for 4 minutes to peel the heat-resistant resin film from the glass substrate, and air-dried at 50 ° C for 1 hour in the atmosphere. Next, the maximum tensile elongation and the maximum tensile stress were determined using the following equipment and conditions.

Measuring device: Tensilon universal material testing machine "RTM-100" (made by Orientec Co., Ltd.)

Determination of sample shape: ribbon

Measuring sample size: length> 70mm, width 10mm

Stretching speed: 50mm / min

Distance between chucks at the start of the test: 50mm

Experimental temperature: 0 ℃ ~ 35 ℃

Number of samples: 10

Calculation method of measurement results: The arithmetic mean of the measured values of 10 samples is obtained.

(2) Measurement of outgassed during heating for 30 minutes at 450 ° C under helium flow

Regarding the heat-resistant resin film obtained in each Example and Comparative Example, the outgas measured during the period of holding for 30 minutes after reaching 450 ° C. was measured by the following equipment and conditions.

Measuring device: Heating unit "Small-4" (manufactured by Toray Research Center Co., Ltd.), GC / MS "QP5050A (7)" (manufactured by Shimadzu Corporation)

Heating condition: increase the temperature from room temperature at 10 ℃ / min, keep it for 30 minutes after reaching 450 ℃

Measurement atmosphere: under helium flow (50mL / min).

Hereinafter, the abbreviations of the compounds used in Synthesis Examples and Examples are described.

p-PDA: p-phenylenediamine

DAE: 4,4'-diaminodiphenyl ether

HAB: 3,3'-dihydroxybenzidine

BPDA: 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride

PMDA: pyromellitic dianhydride

ODPA: 4,4'-oxydiphthalic dianhydride

TPC: terephthaloyl dichloride

NMP: N-methyl-2-pyrrolidone

THPE: 1,1,1-tris (4-hydroxyphenyl) ethane

Surfactant b: BYK-350 (manufactured by BYK-Chemie GmbH)

Surfactant c: Megafac F-444 (DIC) Co., Ltd.

Surfactant d: Polyflow 77 (produced by Kyoeisha Chemical Co., Ltd.).

Synthesis Example 1:

A 200 mL four-necked flask was equipped with a thermometer and a stirring bar with a stirring wing. Then, 90 g of NMP was added under a stream of dry nitrogen, and the temperature was raised to 60 ° C. After raising the temperature, 5.407 g (50.00 mmol) of p-PDA was added with stirring, and washed with 15 g of NMP. It was confirmed that p-PDA was dissolved, 14.49 g (49.25 mmol) of BPDA was added, and 15 g of NMP was washed.

Synthesis Example 2:

A 200 mL four-necked flask was equipped with a thermometer and a stirring bar with a stirring wing. Then, 90 g of NMP was added under a stream of dry nitrogen, and the temperature was raised to 40 ° C. After the temperature was raised, 10.01 g (50.00 mmol) of DAE was added while stirring, and washed with 15 g of NMP. It was confirmed that DAE was dissolved, and 10.74 g (49.25 mmol) of PMDA was put in and washed with 15 g of NMP. Cool down after 4 hours.

Synthesis Example 3:

A 200 mL four-necked flask was equipped with a thermometer and a stirring bar with a stirring wing. Then, 90 g of NMP was added under a stream of dry nitrogen, and the temperature was raised to 60 ° C. After heating up, one side With stirring, 5.407 g (50.00 mmol) of p-PDA was added, and 15 g of NMP was used for washing. It was confirmed that the p-PDA was dissolved, 15.28 g (49.25 mmol) of ODPA was added, and 15 g of NMP was washed.

Synthesis Example 4:

A 200 mL four-necked flask was equipped with a thermometer and a stirring bar with a stirring wing. Then, 90 g of NMP was added under a stream of dry nitrogen, and cooled to 10 ° C or lower. After cooling, 10.81 g (50.00 mmol) of HAB and 13.22 g (150.0 mmol) of glycidyl methyl ether were added with stirring, and washed with 15 g of NMP. Then, 15 g of NMP was added dropwise and 10.15 g (50.00 mmol) of TPC was diluted. After the dropwise addition, the mixture was stirred overnight at room temperature.

Synthesis Example 5:

A 200 mL four-necked flask was equipped with a thermometer and a stirring bar with a stirring wing. Then, 90 g of NMP was added under a stream of dry nitrogen, and the temperature was raised to 60 ° C. After the temperature was raised, 6.488 g (60.00 mmol) of p-PDA was added with stirring, and washed with 15 g of NMP. It was confirmed that the p-PDA was dissolved, 7.061 g (24.00 mmol) of BPDA and 7.525 g (34.50 mmol) of PMDA were added, and 15 g of NMP was washed. Cool down after 4 hours. After cooling, 0.100 g of surfactant d was added to make a varnish.

Synthesis Example 6: Synthesis of photoacid generator a

A thermometer and a stirring bar with a stirring wing were set on a 1000mL four-necked flask. Subsequently, 15.31 g (50.00 mmol) of 1,1,1-tris (4-hydroxyphenyl) ethane and 20.15 g (75.00 mmol) of 5-naphthoquinonediazide sulfonyl chloride were dissolved in 1, under a stream of dry nitrogen. In 450 g of 4-dioxane, adjust to room temperature. Among them, the reaction system does not become 35 ℃ In the above manner, 7.59 g (75.00 mol) of triethylamine mixed with 1,4-dioxane 50 g was added dropwise. After dropping, the mixture was stirred at 30 ° C for 2 hours. The triethylamine salt was filtered, and the filtrate was poured into water. Thereafter, the deposited precipitate was collected by filtration. The precipitate was dried with a vacuum dryer to obtain photoacid generator a. The esterification rate of this naphthoquinonediazide compound was 50%.

Example 1:

The resin solution obtained in Synthesis Example 1 was subjected to pressure filtration using a 1 μm filter to remove foreign substances. Using a coating and developing apparatus Mark-7 (manufactured by Tokyo Electron Co., Ltd.), spin coating was performed on a 6-inch glass substrate so that the film thickness after pre-baking became 15 μm, and thereafter it was performed at 140 ° Pre-bake for 5 minutes. After heating the pre-baked film using a gas oven (INH-21CD manufactured by Koyo Thermo System Co., Ltd.) according to the following first conditions, it was prepared on a glass substrate according to the following second conditions Heat-resistant resin film. Furthermore, the heating under the first condition and the heating under the second condition are performed continuously.

Step 1: Heat at 350 ° C for 30 minutes in an atmospheric atmosphere (oxygen concentration is about 21 vol%).

Step 2: Heat at 400 ° C for 30 minutes in a nitrogen atmosphere with an oxygen concentration of less than 20 ppm.

Among them, the first step is to set the temperature rise from room temperature, and the temperature increase rate is set to 5 ° C / min. The second step is set to increase the temperature from the highest heating temperature in the first step, and the temperature increase rate is set to 5 ° C / min.

Example 2 to Example 10c, Comparative Example 1 to Comparative Example 12:

As described in Table 1, a pre-baked film was produced in the same manner as in Example 1 using the resin solutions obtained in Synthesis Examples 1 to 5 described above. Among them, for Examples 6 to 9 and Comparative Examples 6 to 9, the additives described in Table 1 were used. Next, a heat-resistant resin film was produced in the same manner as in Example 1, except that the maximum heating temperature and heating atmosphere of the first and second steps were set to the conditions described in Table 1. Among them, regarding Comparative Example 12, the following third step is added.

Step 3: Heat at 450 ° C for 30 minutes in an atmospheric atmosphere.

Among them, the third step is to set the temperature rise from room temperature, and the temperature increase rate is set to 5 ° C / min.

The measurement results of the maximum tensile elongation, maximum tensile stress, and outgassing of the heat-resistant resin films obtained in Examples 1 to 10c and Comparative Examples 1 to 12 are shown in Tables 1 to 2.

Example 11

A gas barrier film including a build-up of SiO ₂ and Si ₃ N _{4 was} formed on the heat-resistant resin film obtained in Example 10a by CVD. Next, a TFT is formed, and an insulating film containing Si ₃ N ₄ is formed in a state of covering the TFT. Then, after forming a contact hole in the insulating film, a wiring connected to the TFT through the contact hole is formed.

Furthermore, in order to flatten the unevenness due to the formation of wiring, a flattening film is formed. Then, the obtained planarization film was connected to wiring to form a first electrode containing ITO. Thereafter, a resist is applied and pre-baked, exposed through a mask of a desired pattern, and developed. Using this resist pattern as a mask, patterning was performed by wet etching using ITO etchant. Thereafter, the resist pattern is stripped using a resist stripping solution (mixed solution of monoethanolamine and diethylene glycol monobutyl ether). The substrate after peeling was washed with water and dehydrated by heating to obtain an electrode substrate with a planarization film. Then, an insulating film having a shape covering the periphery of the first electrode is formed.

Furthermore, a hole mask, an organic light-emitting layer, and an electron-transport layer are vapor-deposited in sequence in a vacuum vapor deposition device via a desired pattern mask. Then, a second electrode containing Al / Mg is formed on the entire surface above the substrate. Furthermore, a sealing film including a build-up of SiO ₂ and Si ₃ N _{4 was} formed by CVD. Finally, the glass substrate was irradiated with laser light (wavelength: 308 nm) from the side where the heat-resistant resin film was not formed, and peeled off at the interface with the heat-resistant resin film.

The organic EL display device formed on the heat-resistant resin film is obtained as described above. The voltage is applied via the drive circuit, and as a result, good light emission is shown.

Comparative Example 13

As in Example 11, a gas barrier film was formed on the heat-resistant resin film obtained in Comparative Example 10 by CVD. Subsequently, the formation of the TFT was performed, but it was found that the heat-resistant resin film generated outgassing, and the adhesion between the heat-resistant resin film and the gas barrier film was lowered and peeling occurred, so the subsequent manufacturing steps could not be performed.

[Industry availability]

According to the present invention, it is possible to provide a method for manufacturing a heat-resistant resin film that does not impair the mechanical properties of the heat-resistant resin film and has excellent outgassing properties. The obtained heat-resistant resin film can be preferably used as a surface protective film or interlayer insulating film of a semiconductor element, an insulating layer or a spacer layer of an organic electroluminescence element (organic EL element), a flattening film of a thin film transistor substrate, Insulating layers of organic transistors, flexible printed circuit boards, flexible display substrates, flexible electronic paper substrates, flexible solar cell substrates, flexible color filter substrates, etc.

Claims (12)

A heat-resistant resin film whose outgas generated during heating at 450 ° C for 30 minutes under a helium gas flow is 0.01 μg / cm ² to 4 μg / cm ² , wherein the heat-resistant resin film has the formula (1) Representation structure,

In the chemical formula (1), X represents a tetravalent tetracarboxylic acid residue with a carbon number of 2 or more, and Y represents a divalent diamine residue with a carbon number of 2 or more; m represents a positive integer; and in the chemical formula (1) X is a tetravalent tetracarboxylic acid residue represented by chemical formula (2) or (3) as a main component, and Y is a divalent diamine residue represented by chemical formula (4) as a main component,

The heat-resistant resin film as described in item 1 of the patent application has a maximum tensile stress of 200 MPa or more and 800 MPa or less. A method for manufacturing a heat-resistant resin film includes a step of coating a solution containing a precursor of a heat-resistant resin on a support, and a step of heating the support in multiple stages, and the heat-resistant resin film The manufacturing method is characterized in that the step of heating in multiple stages includes at least the following steps: (A) the first heating step, in an atmosphere with an oxygen concentration of 10 vol% or more, at a temperature above 200 ° C and below 420 ° C Heating at a temperature; and (B) the second heating step, under an atmosphere having an oxygen concentration of 3 vol% or less, heating at a temperature higher than the temperature of the first heating step and 600 ° C or less; the heat-resistant resin is A resin having a structure represented by chemical formula (1),

In the chemical formula (1), X represents a tetravalent tetracarboxylic acid residue with a carbon number of 2 or more, and Y represents a divalent diamine residue with a carbon number of 2 or more; m represents a positive integer; and in the chemical formula (1) X is a tetravalent tetracarboxylic acid residue represented by chemical formula (2) or formula (3) as a main component, and Y is a divalent diamine residue represented by chemical formula (4) as a main component,

The method for manufacturing a heat-resistant resin film as described in item 3 of the patent application range, wherein the solution containing the heat-resistant resin precursor contains at least (a) a photoacid generator, (b) a phenolic hydroxyl group-containing compound and (c) Any one of surfactants. A heating furnace includes: a temperature measuring part, a temperature and temperature adjusting part in the furnace, a temperature and oxygen concentration measuring part in the furnace, an oxygen concentration and a gas flow adjusting part in the furnace, and an adjusting part The flow rate of the heating atmosphere gas in the furnace and a control unit that controls the temperature adjustment unit and the gas flow adjustment unit, the control unit corresponding to the oxygen concentration in the furnace measured by the oxygen concentration measurement unit The gas flow rate adjustment unit is controlled, and after the oxygen concentration reaches a predetermined oxygen concentration, the temperature adjustment unit is controlled so that the temperature in the furnace measured by the temperature measurement unit reaches a predetermined temperature. The heating furnace according to item 5 of the patent application scope, wherein the control unit controls the gas flow rate adjusting unit and the multi-stage heating step including at least a first heating step and a second heating step in sequence A temperature adjustment unit to continuously perform the first heating step and the second heating step, the first heating step is heating at a first temperature in a first oxygen concentration atmosphere, and the second heating step is Heating is performed at the second temperature in the second oxygen concentration atmosphere. The heating furnace according to item 5 or 6 of the patent application scope, wherein the oxygen concentration measuring section includes: a gas sampling port to collect the gas in the furnace; an oxygen concentration meter to measure the oxygen in the gas sampling port Concentration; and a cold trap, located between the oxygen concentration meter and the gas taking port. The method for manufacturing a heat-resistant resin film as described in the third or fourth patent application, which uses the heating furnace as described in any one of the fifth to seventh patent application The heating step is carried out in stages. An image display device including the heat-resistant resin film as described in the first or second patent application. A method for manufacturing an image display device, comprising the steps of: manufacturing a heat-resistant resin film by the method for manufacturing a heat-resistant resin film according to any one of items 3, 4 and 8 of the patent application scope A step of forming a pixel driving element or a colored pixel on the heat-resistant resin film. The method for manufacturing an image display device as described in item 10 of the patent application includes the step of peeling the heat-resistant resin film from the support. The method for manufacturing an image display device as described in item 10 or item 11 of the patent application range, wherein the image display device is an organic electroluminescence display.