WO2012020634A1

WO2012020634A1 - Process for producing metal nanoparticle composite

Info

Publication number: WO2012020634A1
Application number: PCT/JP2011/066706
Authority: WO
Inventors: 龍三新田; 松村　康史
Original assignee: 新日鐵化学株式会社
Priority date: 2010-08-09
Filing date: 2011-07-22
Publication date: 2012-02-16
Also published as: TWI518111B; JP5719847B2; TW201211110A; KR20130098991A; JPWO2012020634A1; CN103052481B; CN103052481A; CN105017562A

Abstract

A process for producing a metal nanoparticle composite wherein metal nanoparticles having a mean particle diameter of 3nm or more are each independently dispersed in a polyimide resin in such a manner that the metal nanoparticles are not in contact with each other and that adjacent nanoparticles are present with a space therebetween, said space being equal to or larger than the larger of the particle diameters of the adjacent metal nanoparticles. The process includes: (a) a step of applying a coating fluid which comprises both a polyimide precursor resin and a metal compound to a substrate so as to give a metal content of 50μg/cm² or less, and drying the resulting coating to form a coating film which has a dry film thickness of 1.7μm or less; and (b) a step of heat-treating the coating film at a temperature of 160 to 450°C not only to reduce the metal ions (or metal salt) contained in the coating film and make the resulting particulate metal (which acts as the metal nanoparticles) deposited and dispersed in the coating film but also to convert the polyimide precursor resin into a polyimide resin and thus form a polyimide resin layer which has a thickness of 1μm or less and an elastic modulus of 10GPa or less.

Description

Method for producing metal fine particle composite

The present invention relates to a method for producing a metal fine particle composite in which metal fine particles are dispersed in a matrix composed of a polyimide resin.

Local Surface Plasmon Resonance (LSPR) is a phenomenon in which fine metal particles with a size of several nanometers to 100 nm or electrons in a metal microstructure resonate by interacting with light of a specific wavelength. is there. Localized surface plasmon resonance has long been used for stained glass that produces vivid colors by mixing fine metal particles inside the glass. In recent years, for example, development of a high-power light emitting laser using the effect of enhancing the light intensity and application to a biosensor using the property that the resonance state changes when molecules are combined are studied.

In order to apply such localized surface plasmon resonance of metal fine particles to a sensor or the like, it is necessary to stably fix the metal fine particles in a matrix such as a synthetic resin. However, when the metal fine particles have a nanometer size, the aggregation and dispersion characteristics change, and for example, dispersion stabilization due to electrostatic repulsion becomes difficult and aggregation tends to occur. Therefore, in a plasmonic device using localized surface plasmon resonance, it is important how the metal fine particles in the matrix can be dispersed in a uniform state.

For example, the following Patent Documents 1 to 4 have been proposed as techniques relating to a method for producing a metal fine particle composite in which metal fine particles are fixed in a matrix such as a resin. In Patent Document 1, as a polymer composite material in which particles are small, particle dispersibility and particle-matrix adhesion are good, and thus have a high elastic modulus, particles are compared with thermoplastic or thermosetting polymer matrices. There is disclosed a polymer-metal cluster composite having an improved elastic modulus obtained by uniformly dispersing and filling metal particles having a diameter of 10 to 20 angstroms with a volume fraction of 0.005 to 0.01%. However, with the production method of Patent Document 1, it was difficult to form a composite of metal fine particles having a particle size of several tens of nanometers or more.

In Patent Document 2, for the purpose of obtaining a dispersion of metal fine particles that can be used for forming a novel conductive film that can be used in place of the electroless plating method or a granular magnetic thin film, a resin substrate containing an ion exchange group is used. A method for producing a fine particle dispersion in which reduction is performed in a gas phase after contacting with a solution containing metal ions is disclosed. In this method, since the reaction proceeds while the metal ions diffuse into the resin during hydrogen reduction, the depth from the surface of the resin substrate to several tens of nanometers (80 nm in the example of Patent Document 2). In addition, there are no metal fine particles. In addition, in the production method disclosed in Patent Document 2, a resin base material containing an ion exchange group is adsorbed or bonded to an ion exchange group contained in a matrix resin by contacting a solution containing metal ions. As a result, the metal ion content is limited and the metal ions are immobilized by the ion exchange groups, so that it is difficult to obtain metal fine particles having a sufficiently large particle diameter.

In Patent Document 3, a polyimide resin film introduced with a carboxyl group by contact with an alkali aqueous solution is brought into contact with a metal ion-containing liquid to dope metal ions into the resin film, and then the reduction temperature of the metal ions or higher in the reducing gas. The first heat treatment is performed to form a layer in which metal nanoparticles are dispersed in the polyimide resin, and the second heat treatment is performed at a temperature different from the first heat treatment temperature. Patent Document 3 describes that the volume filling rate of the metal nanoparticles in the composite film can be controlled by adjusting the thickness of the metal nanoparticle dispersion layer by the second heat treatment. However, as in Patent Document 2, the particle size is a method in which metal ions adsorbed or bonded to ion exchange groups contained in the matrix resin are reduced to form metal fine particles. In addition, since metal ions are immobilized by ion exchange groups, it is difficult to obtain metal fine particles having a sufficiently large particle diameter.

In Patent Document 4, in the process of dispersing metal particles in a polymer matrix, a metal precursor is used as a polymer substance in order to solve problems such as compatibility with the polymer matrix, interface defects, and cohesion between particles. A method is disclosed in which a metal precursor is photoreduced by irradiating ultraviolet rays after being dispersed in a matrix at a molecular level. However, since the method of Patent Document 4 deposits metal fine particles by ultraviolet reduction, it is affected by the ultraviolet irradiation surface, and therefore a gradient occurs in the deposition density of the metal fine particles between the surface layer portion and the deep portion of the matrix. That is, the particle diameter and the filling ratio of the metal fine particles tend to decrease continuously as the matrix proceeds from the surface layer to the deep part. In addition, the particle size of the metal fine particles obtained by photoreduction is maximum at the surface layer portion of the matrix, which is the ultraviolet irradiation surface, but is at most about a dozen nanometers, and a particle size equal to or larger than this particle size. It was difficult to disperse the metal microparticles having a large depth.

Japanese Patent Publication No. 8-16177 Japanese Patent No. 3846331 Japanese Patent No. 4280221 JP 2002-179931 A

When a metal fine particle composite in which metal fine particles are dispersed in a matrix is used for applications such as a sensor using localized surface plasmon resonance, it is important that at least the intensity of the absorption spectrum is large. In general, the sharper the absorption spectrum, the higher the sensitivity of detection. To obtain a sharp and strong absorption spectrum, for example,
1) The size of the metal fine particles is controlled within a predetermined range;
2) The shape of the metal fine particles is uniform,
3) The metal fine particles are separated from each other in a state of maintaining a certain particle interval from the adjacent metal fine particles,
4) The volume filling ratio of the metal fine particles to the metal fine particle composite is controlled within a certain range.
5) The metal fine particles are present from the surface layer portion of the matrix, and are dispersed evenly while maintaining a predetermined inter-particle distance in the thickness direction.
It is necessary for the metal fine particle composite to have structural characteristics such as

The present invention has been devised for the above-mentioned problems that could not be solved by the prior art, and is obtained by independently dispersing metal fine particles having a particle diameter within a predetermined range without agglomerating each other. It aims at providing the manufacturing method of a composite_body | complex.

As a result of intensive studies in view of the above circumstances, the present inventors have controlled the amount of metal contained in the polyimide resin and the thickness of the polyimide resin matrix, and obtained by heat treatment at a temperature within a specific range. The present inventors have found that the fine particle composite satisfies the above requirements and completed the present invention.

That is, in the method for producing a metal fine particle composite of the present invention, the metal particles having an average particle diameter of 3 nm or more are not in contact with each other in the polyimide resin, and the particle diameter of the metal fine particle having the larger particle diameter in the adjacent metal fine particles A metal fine particle composite is produced by being dispersed independently at the above intervals. The metal fine particle composite production method includes the following steps a and b;
a) A coating solution containing a polyimide precursor resin and a metal compound is applied on a substrate so that the content of the metal is 50 μg / cm ² or less, dried, and the thickness after drying is Forming a coating film of 1.7 μm or less,
b) The coating film is heat-treated at a temperature in the range of 160 ° C. or more and 450 ° C. or less, thereby reducing the metal ions (or metal salt) in the coating film and precipitating particulate metal that becomes metal fine particles. And a step of dispersing in the coating film and imidizing the polyimide precursor resin in the coating film to form a polyimide resin layer having a thickness of 1 μm or less and an elastic modulus of 10 GPa or less,
It has.

In a first preferred embodiment of the method for producing a metal fine particle composite of the present invention, the metal fine particle composite has an average particle diameter of the metal fine particles in the range of 3 nm to 25 nm and a volume fraction of the metal fine particles. It may be in the range of 0.05% to 1% with respect to the composite. In this case, the metal content in the coating solution in the step a is in the range of 0.5 μg / cm ² or more and 10 μg / cm ² or less, and the thickness of the coating film after drying is 500 nm or more and 1 It may be within a range of 7 μm or less. Furthermore, the thickness of the polyimide resin layer in the step b may be in the range of 300 nm to 1 μm.

In a second preferred embodiment of the method for producing a metal fine particle composite of the present invention, the metal fine particle composite has an average particle diameter of the metal fine particles in the range of 3 nm or more and 30 nm or less, and the volume fraction thereof is the metal fine particles. It may be within a range of 0.2% to 5% with respect to the composite. In this case, the metal content in the coating solution in the step a is in the range of 10 μg / cm ^{2 to} 50 μg / cm ² and the thickness of the coating film after drying is 500 nm to 1.7 μm. It may be within the following range. Furthermore, the thickness of the polyimide resin layer in the step b may be in the range of 300 nm to 1 μm and the elastic modulus may be in the range of 3 GPa to 10 GPa.

In a third preferred embodiment of the method for producing a metal fine particle composite of the present invention, the metal fine particle composite has an average particle diameter of the metal fine particles in the range of 3 nm to 30 nm and a volume fraction of the metal fine particles. It may be within a range of 0.5% or more and 5% or less with respect to the composite. In this case, the metal content in the coating solution in the step a is in the range of 5 μg / cm ^{2 to} 10 μg / cm ² and the thickness of the coating film after drying is 150 nm to 500 nm. It may be within the range. Furthermore, the thickness of the polyimide resin layer in the step b may be in the range of 100 nm to 300 nm and the elastic modulus may be in the range of 5 MPa to 10 GPa.

In a fourth preferred embodiment of the method for producing a metal fine particle composite of the present invention, the metal fine particle composite has an average particle diameter of the metal fine particles in the range of 5 nm or more and 35 nm or less, and the volume fraction thereof is a metal. It may be in the range of 1% to 15% with respect to the fine particle composite. In this case, the metal content in the coating solution in the step a is in the range of 10 μg / cm ^{2 to} 30 μg / cm ² and the thickness of the coating film after drying is 150 nm to 500 nm. It may be within the range. Furthermore, the thickness of the polyimide resin layer in the step b may be in the range of 100 nm to 300 nm and the elastic modulus may be in the range of 0.5 GPa to 10 GPa.

Further, in the method for producing a metal fine particle composite according to the present invention, the step b may be performed in an inert gas atmosphere.

In the method for producing a metal fine particle composite according to the present invention, the metal compound may be a precursor of Au.

In the method for producing a metal fine particle composite of the present invention, since metal fine particles are precipitated by reduction from the state of metal ions (or metal salts) inside the polyimide precursor resin, the metal compound is contained in the polyimide precursor resin. The amount can be easily adjusted, and the content of the metal fine particles dispersed in the polyimide resin can be easily adjusted. Therefore, relatively easily, metal fine particles having an average particle diameter of 3 nm or more do not contact each other in the polyimide resin, and are separated from each other at an interval equal to or larger than the particle diameter of the larger metal fine particle in the adjacent metal fine particles. Dispersed metal fine particle composites can be produced. Moreover, since the reduction treatment is by heating, it is possible to disperse the metal fine particles in the matrix resin while maintaining a certain inter-particle distance in the matrix resin by utilizing thermal diffusion of the precipitated metal fine particles, and Metal fine particles dispersed at a certain inter-particle distance are present from the surface layer portion of the matrix resin.

Further, in the method for producing a metal fine particle composite according to the present invention, the imidization of the polyimide precursor resin can be completed using the heat used in the reduction treatment, so that the production process can be simplified.

Since the metal fine particle composite produced by the method of the present invention has the above-described structural characteristics, it includes fields such as a pressure sensor using a localized surface plasmon effect, and includes, for example, an electromagnetic shielding material and a magnetic noise absorbing material. It can be applied to various industrial fields such as high thermal conductive resin materials.

Next, embodiments of the present invention will be described in detail. In the method for producing a metal fine particle composite according to an embodiment of the present invention, metal fine particles having an average particle diameter of 3 nm or more are not in contact with each other in a polyimide resin, and metal fine particles having a larger particle diameter in adjacent metal fine particles This is a method for producing a metal fine particle composite that produces a metal fine particle composite that is dispersed independently of each other at an interval equal to or larger than the particle diameter. This method includes the following steps a and b.
a) A coating solution containing a polyimide precursor resin and a metal compound is applied on a substrate so that the content of the metal is 50 μg / cm ² or less, dried, and the thickness after drying is The process of forming the coating film of 1.7 micrometers or less.
b) The coating film is heat-treated at a temperature in the range of 160 ° C. or more and 450 ° C. or less, thereby reducing the metal ions (or metal salt) in the coating film and precipitating particulate metal that becomes metal fine particles. The step of dispersing in the coating film and imidizing the polyimide precursor resin in the coating film to form a polyimide resin layer having a thickness of 1 μm or less and an elastic modulus of 10 GPa or less.

Hereinafter, the method of the present invention will be described by dividing it into preferred embodiments based on the average particle diameter and volume fraction of metal fine particles. The “volume fraction” is a value indicating the total volume of the metal fine particles in a certain volume of the metal fine particle composite as a percentage.

[First Embodiment]
In the method for producing the metal fine particle composite according to the first embodiment of the present invention, the metal fine particles having an average particle diameter in the range of 3 nm to 25 nm are not in contact with each other in the polyimide resin. The metal fine particles having the larger particle diameter are dispersed independently of each other (preferably completely independently) at intervals equal to or larger than the particle diameter, and the volume fraction of the metal fine particles is 0. A metal fine particle composite in the range of 05% or more and 1% or less is manufactured, and includes the following steps a and b. Here, the polyimide resin is mainly composed of a polyimide resin imidized by heating and dehydrating and cyclizing the polyimide precursor resin. The polyimide resin is preferably used because it has properties excellent in heat resistance and dimensional stability as compared with other synthetic resins such as thermosetting resins such as epoxy resins, phenol resins, and acrylic resins. In addition, the polyimide resin is advantageous in that it has heat resistance at a temperature of at least 160 ° C. because heat treatment is performed in the process of forming the metal fine particles.

[Step a: Coating film forming step]
In the method for producing a metal fine particle composite of the present embodiment, a coating film is formed by applying a coating liquid containing a polyimide precursor resin and a metal compound onto a substrate and drying.

The substrate used in step a is not particularly limited, and may be, for example, a polyimide resin film (sheet), and other examples include a metal foil, a glass plate, a resin film, and ceramics. it can. The metal fine particle composite body manufactured by the manufacturing method of the present embodiment may be peeled off from the base material or may remain in the state where the base material is attached. For example, when utilizing the localized surface plasmon resonance of the light transmission system with the metal fine particle composite manufactured in the present embodiment attached to the substrate, the substrate should be light transmissive. For example, a glass substrate, a transparent synthetic resin substrate, or the like can be used. Examples of the transparent synthetic resin include polyimide resin, PET resin, acrylic resin, MS resin, MBS resin, ABS resin, polycarbonate resin, silicone resin, siloxane resin, and epoxy resin.

As the polyimide precursor resin which is a polyimide resin precursor, a known polyimide precursor resin obtained from a known acid anhydride and diamine can be used. The polyimide precursor resin is prepared by, for example, dissolving tetracarboxylic dianhydride and diamine in an organic solvent in approximately equimolar amounts and stirring them at a temperature in the range of 0 to 100 ° C. for 30 minutes to 24 hours to cause a polymerization reaction. can get. In the reaction, the reaction components are preferably dissolved so that the obtained polyimide precursor resin is in the range of 5 to 30% by weight, preferably in the range of 10 to 20% by weight, in the organic solvent. As the organic solvent used in the polymerization reaction, it is preferable to use a polar one. Examples of the organic polar solvent include N, N-dimethylformamide, N, N-dimethylacetamide (DMAc), N-methyl-2 -Pyrrolidone, 2-butanone, dimethyl sulfoxide, dimethyl sulfate, cyclohexanone, dioxane, tetrahydrofuran, diglyme, triglyme and the like. Two or more of these solvents can be used in combination, and some aromatic hydrocarbons such as xylene and toluene can also be used.

The synthesized polyimide precursor resin is used as a solution. Usually, it is advantageous to use as a reaction solvent solution, but if necessary, it can be concentrated, diluted or replaced with another organic solvent. The solution thus prepared can be used as a coating solution by adding a metal compound.

The polyimide precursor resin is preferably selected so that the polyimide resin after imidization contains a thermoplastic or low thermal expansion polyimide resin. In addition, as a polyimide resin, the heat resistant resin which consists of a polymer which has an imide group in structures, such as a polyimide, a polyamideimide, a polybenzimidazole, a polyimide ester, a polyetherimide, a polysiloxaneimide, can be mentioned, for example.

Examples of the diamine that can be suitably used for preparing the polyimide precursor resin include 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl, 4,4′-diaminodiphenyl ether, and 2′-methoxy- 4,4'-diaminobenzanilide, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl ] Propane, 2,2′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dihydroxy-4,4′-diaminobiphenyl, 4,4′-diaminobenzanilide and the like. Diamines include 2,2-bis- [4- (3-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] sulfone, and bis [4- (3-aminophenoxy) phenyl. ] Sulfone, bis [4- (4-aminophenoxy)] biphenyl, bis [4- (3-aminophenoxy) biphenyl, bis [1- (4-aminophenoxy)] biphenyl, bis [1- (3-aminophenoxy) )] Biphenyl, bis [4- (4-aminophenoxy) phenyl] methane, bis [4- (3-aminophenoxy) phenyl] methane, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy)] benzophenone, bis [4- (3-aminophenoxy)] benzophenone, bis [4,4 '-(4-aminophenoxy)] Ben Anilide, bis [4,4 '-(3-aminophenoxy)] benzanilide, 9,9-bis [4- (4-aminophenoxy) phenyl] fluorene, 9,9-bis [4- (3-aminophenoxy) Preferred examples include phenyl] fluorene and the like.

Other diamines include, for example, 2,2-bis- [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis- [4- (3-aminophenoxy) phenyl] hexafluoropropane, 4 , 4'-methylenedi-o-toluidine, 4,4'-methylenedi-2,6-xylidine, 4,4'-methylene-2,6-diethylaniline, 4,4'-diaminodiphenylpropane, 3,3 ' -Diaminodiphenylpropane, 4,4'-diaminodiphenylethane, 3,3'-diaminodiphenylethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 3, 3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,3-diaminodiphenyl ether, 3,4'-diaminodiphenyl Ether, benzidine, 3,3'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 4,4 ''-diamino-p-terphenyl, 3, 3 ''-diamino-p-terphenyl, m-phenylenediamine, p-phenylenediamine, 2,6-diaminopyridine, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-amino) Phenoxy) benzene, 4,4 '-[1,4-phenylenebis (1-methylethylidene)] bisaniline, 4,4'-[1,3-phenylenebis (1-methylethylidene)] bisaniline, bis (p- Aminocyclohexyl) methane, bis (p-β-amino-t-butylphenyl) ether, bis (p-β-methyl-δ-aminopentyl) benzene, p-bis (2-methyl-4-aminopentyl) benzene, p-bis (1,1-dimethyl-5-aminopentyl) benzene, 1,5-diaminonaphthalene, 2,6-diaminonaphtha 2,4-bis (β-amino-t-butyl) toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine , P-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-diamino-1,3,4-oxadiazole, piperazine and the like.

Particularly preferred diamine components include 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl (TFMB), 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB), 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane (DANPG), 2,2-bis [4- (4-aminophenoxy) phenyl] propane (BAPP), 1,3-bis (3 -Aminophenoxy) benzene (APB), paraphenylenediamine (p-PDA), 3,4'-diaminodiphenyl ether (DAPE34), one or more diamines selected from 4,4'-diaminodiphenyl ether (DAPE44) .

Examples of the acid anhydride suitably used for the preparation of the polyimide precursor resin include pyromellitic anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4 Examples include '-diphenylsulfonetetracarboxylic dianhydride and 4,4'-oxydiphthalic anhydride. Moreover, 2,2 ', 3,3'-, 2,3,3', 4'- or 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 2,3 ', 3,4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, 2,3 ', 3,4'-diphenyl ether tetracarboxylic dianhydride Bis (2,3-dicarboxyphenyl) ether dianhydride and the like are also preferred. In addition, 3,3``, 4,4 ''-, 2,3,3 '', 4 ''-or 2,2 '', 3,3 ''-p-terphenyltetra Carboxylic dianhydride, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) -propane dianhydride, bis (2,3- or 3.4-dicarboxyphenyl) methane dianhydride, bis Preferred examples include (2,3- or 3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis (2,3- or 3,4-dicarboxyphenyl) ethane dianhydride and the like.

Particularly preferred acid anhydrides include pyromellitic anhydride (PMDA), 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA), 3,3', 4,4'-benzophenone tetracarboxylic acid One or more acids selected from acid dianhydride (BTDA), 4,4'-oxydiphthalic acid anhydride (ODPA), 3,3 ', 4,4'-diphenylsulfone tetracarboxylic dianhydride (DSDA) Anhydrides are mentioned.

Each of diamine and acid anhydride may be used alone or in combination of two or more. In addition, diamines and acid anhydrides other than those described above can be used in combination.

In this embodiment, in order to prepare a polyimide precursor resin solution, a commercially available product can also be suitably used as a solution containing a polyimide precursor resin. Examples of the thermoplastic polyimide precursor resin solution include thermoplastic polyimide precursor resin varnish SPI-200N (trade name), SPI-300N (trade name), and SPI-1000G (manufactured by Nippon Steel Chemical Co., Ltd.). Product name), Toray Industries Co., Ltd. # 3000 (product name), etc. are mentioned. Examples of the non-thermoplastic polyimide precursor resin solution include U-Varnish-A (trade name) and U-Varnish-S (trade name) which are non-thermoplastic polyimide precursor resin varnishes manufactured by Ube Industries, Ltd. ) And the like.

When the metal fine particle composite body produced in the present embodiment is applied to, for example, an application utilizing localized surface plasmon resonance of a light transmission system, as a polyimide resin exhibiting transparency or colorlessness, the intramolecular, molecular It is preferable to use those that are difficult to form a charge transfer (CT) complex between them, such as aromatic polyimide resins having steric substituents in bulk, alicyclic polyimide resins, fluorine-based polyimide resins, silicon-based polyimide resins, etc. .

Examples of the substituent having a bulky steric structure include a fluorene skeleton and an adamantane skeleton. Such a bulky steric substituent is substituted with either an acid anhydride residue or a diamine residue in the aromatic polyimide resin, or an acid anhydride residue and a diamine residue. Both may be substituted. Examples of the diamine having a bulky steric substituent include 9,9-bis (4-aminophenyl) fluorene.

An alicyclic polyimide resin is a resin formed by polymerizing an alicyclic acid anhydride and an alicyclic diamine. The alicyclic polyimide resin can also be obtained by hydrogenating an aromatic polyimide resin.

Fluorine-based polyimide resins are, for example, acid anhydrides and / or diamines in which monovalent elements bonded to carbon such as alkyl groups and phenyl groups are substituted with fluorine, perfluoroalkyl groups, perfluoroaryl groups, perfluoroalkoxy groups, perfluorophenoxy groups, etc. Is a resin formed by polymerizing. As the fluorine atom, any one in which all or part of the monovalent element is substituted can be used, but one in which 20% or more of the monovalent element is substituted with the fluorine atom is preferable.

The silicon-based polyimide resin is a resin obtained by polymerizing a silicon-based diamine and an acid anhydride.

For example, such a transparent polyimide resin preferably has a light transmittance of 80% or more at a wavelength of 400 nm and a visible light average transmittance of 90% or more at a thickness of 10 μm.

Among the polyimide resins, a fluorine-based polyimide resin excellent in transparency is particularly preferable. As the fluorine-based polyimide resin, a polyimide resin having a structural unit represented by the general formula (1) can be used. Here, in General Formula (1), Ar ₁ represents a tetravalent aromatic group represented by Formula (2), Formula (3), or Formula (4), and Ar ₂ represents Formula (5), Formula ( 6) represents a divalent aromatic group represented by formula (7) or formula (8), and p represents the number of repeating structural units.

R independently represents a fluorine atom or a perfluoroalkyl group, Y represents a divalent group represented by the following structural formula, R ₁ represents a perfluoroalkylene group, and n represents a number from 1 to 19. Means.

In the above general formula (1), Ar ₂ can be referred to as a diamine residue, and Ar ₁ can be referred to as an acid anhydride residue. The tetracarboxylic acid, acid chloride, esterified compound and the like (hereinafter referred to as “acid anhydride etc.”) that can be used in the same manner as above will be described. However, the fluorine-based polyimide resin is not limited to those obtained from the diamine and acid anhydride described herein.

As a raw material diamine to be Ar ₂ , any alkyl group excluding an amino group in the molecule, any monovalent element bonded to carbon such as a phenyl ring, etc., having fluorine or a perfluoroalkyl group can be used. For example, 3,4,5,6, -tetrafluoro-1,2-phenylenediamine, 2,4,5,6-tetrafluoro-1,3-phenylenediamine, 2,3,5,6 -Tetrafluoro-1,4-phenylenediamine, 4,4'-diaminooctafluorobiphenyl, bis (2,3,5,6-tetrafluoro-4-aminophenyl) ether, bis (2,3,5,6) -Tetrafluoro-4-aminophenyl) sulfone, hexafluoro-2,2'-bistrifluoromethyl-4,4'-diaminobiphenyl, 2,2-bis (trifluoro) May be mentioned methyl) -4,4'-diaminobiphenyl and the like.

Examples of the raw acid anhydride to be Ar ₁ include 1,4-difluoropyromellitic acid, 1-trifluoromethyl-4-fluoropyromellitic acid, 1,4-di (trifluoromethyl) pyromellitic acid, 1,4-di (pentafluoroethyl) pyromellitic acid, hexafluoro-3,3 ′, 4,4′-bisphenyltetracarboxylic acid, hexafluoro-3,3 ′, 4,4′-benzophenonetetracarboxylic acid 2,2-bis (3,4-dicarboxytrifluorophenyl) hexafluoropropane, 1,3-bis (3,4'-dicarboxytrifluorophenyl) hexafluoropropane, 1,4-bis (3,4 4-dicarboxytrifluorophenoxy) tetrafluorobenzene, hexafluoro-3,3 ′, 4,4′-oxybisphthalic acid, 4,4 ′-(he Such sub-fluoro isopropylidene) diphthalic acid.

As the metal compound contained in the coating liquid together with the polyimide precursor resin, any material can be used as long as it can precipitate metal particles (or metal salts) contained in the polyimide precursor resin by heat reduction. Although there is no particular limitation, for example, gold (Au), silver (Ag), copper (Cu), cobalt (Co), nickel (Ni), palladium (Pd), platinum (Pt), tin (Sn), rhodium ( Rh), metal compounds containing a precursor such as iridium (Ir). Moreover, these metal compounds can also be used 1 type or in combination of 2 or more types. For example, gold (Au), silver (Ag), copper (Cu), palladium (Pd), platinum (Pt), tin (Sn), which can be suitably used as the metal species exhibiting localized surface plasmon resonance, Examples thereof include rhodium (Rh) and iridium (Ir). Particularly, the metal compound suitably used in the manufacturing method of the present embodiment is a compound of gold (Au) or silver (Ag). As the metal compound, a salt of the metal, an organic carbonyl complex, or the like can be used. Examples of the metal salt include hydrochloride, sulfate, acetate, oxalate, and citrate. Examples of the organic carbonyl compound capable of forming an organic carbonyl complex with the above metal species include β-diketones such as acetylacetone, benzoylacetone and dibenzoylmethane, and β-ketocarboxylic acid esters such as ethyl acetoacetate. it can.

Preferable specific examples of the metal compound include H [AuCl ₄ ], Na [AuCl ₄ ], AuI, AuCl, AuCl ₃ , AuBr ₃ , NH ₄ [AuCl ₄ ] · n ₂ H ₂ O, Ag (CH ₃ COO), AgCl _{_{_{, AgClO 4, Ag 2 CO 3}}} , AgI, Ag 2 SO 4, AgNO 3, Ni (CH 3 COO) 2, Cu (CH 3 COO) 2, CuSO 4, CuSO 4, CuSO 4, CuCl 2, CuSO 4, CuBr ₂ , Cu (NH ₄ ) ₂ Cl ₄ , CuI, Cu (NO ₃ ) ₂ , Cu (CH ₃ COCH ₂ COCH ₃ ) ₂ , CoCl ₂ , CoCO ₃ , CoSO ₄ , Co (NO ₃ ) ₂ , NiSO ₄ _{_{, NiCO 3, NiCl 2, NiBr}} 2, Ni (NO 3) 2, NiC 2 O 4, Ni (H 2 PO 2) 2, Ni (CH 3 C _{_{_{CH 2 COCH 3) 2, Pd}}} (CH 3 COO) 2, PdSO 4, PdCO 3, PdCl 2, PdBr 2, Pd (NO 3) 2, Pd (CH 3 COCH 2 COCH 3) 2, SnCl 2, IrCl 3 , RhCl _{3 and the} like.

Depending on the metal species, a metal ion generated by dissociation of a metal compound may cause a three-dimensional cross-linking reaction with the polyimide precursor resin. For this reason, the thickening and gelation of the coating solution proceed with the passage of time, which may make it difficult to use the coating solution. In order to prevent such thickening and gelation, it is preferable to add a viscosity modifier as a stabilizer in the coating solution. By the addition of the viscosity modifier, instead of the metal ions in the coating solution forming a chelate complex with the polyimide precursor resin, the viscosity modifier and the metal ions form a chelate complex. As described above, the viscosity modifier blocks the three-dimensional cross-linking between the polyimide precursor resin and the metal ions, and suppresses thickening and gelation.

As the viscosity modifier, it is preferable to select a low molecular organic compound that is highly reactive with metal ions (that is, capable of forming a metal complex). The molecular weight of the low molecular weight organic compound is preferably in the range of 50 to 300. Specific examples of such a viscosity modifier include acetylacetone, ethyl acetoacetate, pyridine, imidazole, picoline and the like. The viscosity modifier is added in an amount of 1 to 50 mol, preferably 2 to 20 mol, per mol of the chelate complex compound that can be formed.

The compounding amount of the metal compound in the coating solution is in the range of 3 to 80 parts by weight, preferably in the range of 10 to 60 parts by weight, based on 100 parts by weight of the total solid content of the polyimide precursor resin and the metal compound. To be. In this case, if the metal compound is less than 3 parts by weight, it is difficult to make the average particle diameter of the metal fine particles 3 nm or more. When the amount exceeds 80 parts by weight, a metal salt that cannot be dissolved in the coating solution may precipitate or metal fine particles may easily aggregate. Here, the average particle diameter means an average value (median diameter) of the diameters of the metal fine particles, and is an area average diameter when 100 arbitrary metal fine particles are measured. The average particle diameter can be confirmed by observing metal fine particles with a transmission electron microscope (TEM).

In the coating liquid, for example, a leveling agent, an antifoaming agent, an adhesion-imparting agent, a crosslinking agent, etc. can be blended as optional components other than the above components.

The method for applying the coating solution containing the metal compound is not particularly limited, and for example, it can be applied with a coater such as a comma, die, knife, lip, etc. Among them, a coating film is uniformly formed. It is preferable to use a spin coater, gravure coater, or bar coater that can easily control the thickness of the coating film with high accuracy. The coating solution has a metal content derived from the metal compound (hereinafter sometimes abbreviated as “metal content”) in the range of 0.5 μg / cm ² to 10 μg / cm ² , preferably 3 μg / cm. in the range of ^² ~ ^10μg / cm ^2, more preferably is applied onto a substrate so as to be in the range of ^{6μg / cm 2 ~ 10μg / cm} 2. For the amount of metal per unit area of the coating film obtained by coating, the content of the metal in the coating solution is determined in advance, and a method of controlling by the film thickness of the coating film, or the film thickness of the coating film in advance There is a method of determining and controlling by the metal content in the coating solution. The thickness of the coating film is such that the thickness after drying is in the range of 500 nm to 1.7 μm, preferably in the range of 1 μm to 1.7 μm, and the thickness of the polyimide resin layer after imidization is 300 nm to The thickness is in the range of 1 μm, preferably in the range of 600 nm to 1 μm. If the thickness of the polyimide resin layer after imidization is less than 300 nm, the metal fine particles tend to agglomerate. On the other hand, if the thickness exceeds 1 μm, the metal fine particles formed in the polyimide resin layer tend to be small. The average particle diameter of the metal fine particles tends to vary between the surface layer portion and the deep portion of the resin layer.

In addition, in order to control the average particle diameter and the interparticle distance of the metal fine particles, the metal content range (0.5 μg / cm ² to 10 μg / cm ² ) in the coating film and the polyimide after imidization are used. After satisfying the conditions of the resin layer thickness range (300 nm to 1 μm), the content A [μg / cm ² ] of the metal content in the coating film and the thickness B [ More preferably, the relationship with nm] satisfies the following formula.
0.1 ≦ (A / B) × 100 ≦ 2.0 (i)

After applying the coating solution containing the metal compound, it is dried to form a coating film. In drying, it is preferable to control the temperature so that imidization due to the progress of dehydration and ring closure of the polyimide precursor resin is not completed. The drying method is not particularly limited, and for example, the drying may be performed under a temperature condition in the range of 60 to 200 ° C. and taking a time in the range of 1 to 60 minutes, preferably 60 to 150 ° C. It is preferable to perform drying under temperature conditions within the range. The coating film after drying may have a part of the structure of the polyimide precursor resin imidized, but the imidization rate is 50% or less, more preferably 20% or less, and the structure of the polyimide precursor resin is 50% or more. It is good to leave. The imidation ratio of the polyimide precursor resin is determined by measuring the infrared absorption spectrum of the film by a transmission method using a Fourier transform infrared spectrophotometer (commercially available product, for example, FT / IR620 manufactured by JASCO Corporation). with respect to the benzene ring carbon hydrogen bonds of 1,000 cm ^-1, it is calculated from the absorbance from the imide groups of 1,710cm ^-1.

The coating film may be a single layer or a laminated structure formed from a plurality of coating films. In the case of a plurality of layers, other polyimide precursor resins can be sequentially applied on the polyimide precursor resin layer composed of different components. When the polyimide precursor resin layer is composed of three or more layers, the polyimide precursor resin having the same configuration may be used twice or more. Two layers or a single layer, in particular a single layer, having a simple layer structure can be advantageously obtained industrially.

In addition, a single layer or a plurality of polyimide precursor resin layers are laminated on a sheet-like support member, and once imidized to form a single layer or a plurality of polyimide resin layers, a coating film is further formed thereon. It is also possible to form. In this case, in order to improve the adhesion between the polyimide resin layer and the coating film layer, the surface of the polyimide resin layer is preferably surface-treated with plasma. By this surface treatment with plasma, the surface of the polyimide resin layer can be roughened or the chemical structure of the surface can be changed. Thereby, the wettability of the surface of the polyimide resin layer is improved, the affinity with the solution of the polyimide precursor resin is increased, and the coating film can be stably held on the surface.

[Step b: Heat treatment step]
In step b, the coating film obtained as described above is heat treated in the range of 160 to 450 ° C., preferably in the range of 200 to 400 ° C., more preferably in the range of 300 to 400 ° C. Ions (or metal salts) are reduced to deposit particulate metal that becomes metal fine particles. When the heat treatment temperature is less than 160 ° C., it may be difficult to make the average particle diameter of the metal fine particles obtained by reducing metal ions (or metal salts) equal to or more than the above lower limit. On the other hand, when the heat treatment temperature exceeds 450 ° C., the polyimide resin layer is decomposed by heat, and it is difficult to control the particle spacing between the metal fine particles. By setting the heat treatment temperature to 160 ° C. or higher, the heat diffusion inside the polyimide resin layer (or polyimide precursor resin layer) of the metal fine particles deposited by reduction can be sufficiently performed. Imidization can be performed, and the process of imidization by heating can be omitted again.

As will be described later, the heating time can be determined according to the target interparticle distance, and further according to the heating temperature and the content of metal ions (or metal salts) contained in the coating film. When the heating temperature is 160 ° C., it can be set within a range of 10 to 180 minutes, and when the heating temperature is 450 ° C., it can be set within a range of 1 to 60 minutes.

In addition, the polyimide precursor resin in the coating film is imidized by this heat treatment, and the content of the metal fine particles is in the range of 0.5 μg / cm ² to 10 μg / cm ² , preferably 3 μg / cm ² to 10 μg / cm ^2. A polyimide resin layer having a thickness in the range of 6 μg / cm ² to 10 μg / cm ² and a thickness in the range of 300 nm to 1 μm, preferably in the range of 600 nm to 1 μm is formed.

As described above, the average particle diameter and interparticle distance of the metal fine particles are determined by i) the heat treatment temperature in the heat treatment step, ii) the content of metal ions (or metal salts) contained in the coating film, and iii) the final formation. The thickness of the polyimide resin layer to be controlled can be controlled. In the case where the heat treatment temperature is constant and the absolute amount of metal ions (or metal salts) contained in the coating film is different, or the absolute amount of metal ions (or metal salts) contained in the coating film is different. In the case where the thickness of the coating film is different even if it is constant, it has been found that the particle diameters of the deposited metal fine particles are different. In addition, when the heat treatment is performed without controlling the heat treatment temperature, the content of metal ions (or metal salts) contained in the coating film, and the thickness of the polyimide resin layer finally formed, the interparticle distance is reduced. It has also been found that metal fine particles aggregate on the surface of the polyimide resin layer to form islands.

Based on the above knowledge, it has been found that the average particle diameter and interparticle distance of the metal fine particles can be controlled by controlling the above conditions i) to iii). That is, by controlling the conditions i) to iii), the average particle diameter of the metal fine particles is controlled within the range of 3 nm to 25 nm, and the metal fine particles thus controlled have their respective particle spacings (interparticle distances). L is the particle size of the larger metal particles in neighboring metal fine particles (D _L) or higher, i.e., it will be present in relation L ≧ D _L. Metal particle composite of the present embodiment, due to the provision of the requirements of step a and step b, the deposited metal particles thermal diffusion is facilitated, those over the particle diameter D _L of the larger in the metal particles adjacent It will be in the state disperse | distributed in the polyimide resin by the distance L between particles. Although there is no particular problem even if the interparticle distance L is large, the interparticle distance L in the metal fine particles that are dispersed using thermal diffusion is closely related to the particle diameter D of the metal fine particles and the volume fraction of the metal fine particles. Therefore, the upper limit of the interparticle distance L is preferably controlled by the lower limit value of the volume fraction of the metal fine particles.

In the present embodiment, the volume fraction of the metal fine particles is in the range of 0.05 to 1%, preferably in the range of 0.1 to 1% with respect to the metal fine particle composite. By setting the volume fraction within the above range, the interparticle distance L of the metal fine particles can be controlled. The volume fraction of the metal fine particles can be adjusted mainly by the content of the metal in the coating solution in step a.

Further, the hardness of the polyimide precursor resin / polyimide resin when performing the heat treatment in step b affects the thermal diffusibility of the metal fine particles. That is, the softer the polyimide precursor resin / polyimide resin at the heat treatment temperature, the easier the thermal diffusion of the metal fine particles, whereas the harder the polyimide precursor resin / polyimide resin, the less the thermal diffusion of the metal fine particles. From this point of view, in order to form a controlled metal particle composite so as to satisfy the relationship of L ≧ D _L, the elastic modulus of the polyimide precursor resin / polyimide resin when performing the heat treatment in step b (i.e. It is preferable to adjust the elastic modulus when heated within a temperature range of 160 to 450 ° C. In addition, although the postscript Example shows the elasticity modulus of the polyimide resin after hardening, this elasticity modulus becomes a parameter | index reflecting the elasticity modulus of the polyimide precursor resin / polyimide resin in the heat treatment process of the process b. That is, the higher the elastic modulus of the cured polyimide resin, the higher the elastic modulus of the polyimide precursor resin / polyimide resin in the heat treatment process of step b, and the lower the elastic modulus of the cured polyimide resin, the polyimide in the heat treatment process of step b. Since the elastic modulus of the precursor resin / polyimide resin becomes low, the thermal diffusion of the metal fine particles can be controlled by controlling the elastic modulus of the cured polyimide resin. The elastic modulus of the cured polyimide resin is preferably adjusted within a range of, for example, 1 × 10 ⁵ or more and 1 × 10 ¹⁰ Pa or less.

The features of the manufacturing method of the present embodiment are that it can be handled with simple equipment without any restriction from lab scale to production scale, and that it can handle not only single wafer type but also continuous type without special ingenuity. Is advantageous. Further, in step b, for example, it can be performed in an inert gas atmosphere such as Ar or N ₂ , in a vacuum of 1 to 5 KPa, or in the air. As a method for depositing the particulate metal (reduction treatment method), gas phase reduction using a reducing gas such as hydrogen or light (ultraviolet) reduction is not suitable. In the gas phase reduction, metal fine particles are not formed near the surface of the polyimide resin layer, the thermal decomposition of the polyimide resin is promoted by the reducing gas, and it becomes difficult to control the particle interval of the metal fine particles. Further, in photoreduction, the density of metal fine particles tends to vary in the vicinity of the surface and in the deep part due to the light transmittance derived from the polyimide resin layer, and it is difficult to control the particle diameter D and the interparticle distance L of the metal fine particles. Besides, the reduction efficiency is low. In addition, the particulate metal deposited in the process of step b is Au (gold), Ni (nickel) or the like, and the particulate metal itself promotes the decomposition of the polyimide resin (or polyimide precursor resin) in a high temperature atmosphere ( In the case of a metal species having a so-called catalytic function, it is preferably carried out in an inert gas atmosphere such as Ar or N ₂ and in a vacuum of 1 to 5 KPa.

In step b, since the imidation of the polyimide precursor resin can be completed using the heat used in the reduction treatment, the steps from the precipitation of the metal fine particles to the imidization can be performed in one pot, and the production process It can be simplified.

In the reduction by heat treatment, metal ions (or metal salts) present in the coating film can be reduced, and individual metal fine particles can be precipitated in an independent state by thermal diffusion. The metal fine particles formed in this way are in a state in which the inter-particle distance L is not less than a certain value, and the shape is substantially uniform, and the metal fine particles are not unevenly three-dimensionally from the surface portion of the polyimide resin in the polyimide resin layer. To be distributed. In addition, by controlling the structural unit of the resin constituting the polyimide resin, or by controlling the absolute amount of metal ions (or metal salts) and the volume fraction of the metal fine particles, the average particle diameter of the metal fine particles and the polyimide resin layer It is also possible to control the distribution state of the metal fine particles therein.

Further, the coating film is formed so that the content of the metal fine particles in the polyimide resin layer is in the range of 6 μg / cm ² to 10 μg / cm ² and the thickness of the polyimide resin layer is in the range of 600 nm to 870 nm. By forming, a metal fine particle layer in which metal fine particles having an average particle diameter of 13 nm or more are dispersed can be formed.

In addition, in this manufacturing method, arbitrary processes, such as an etching process, can also be performed other than the said process a and process b, for example.

As described above, according to the method for producing a metal fine particle composite of the present invention, metal ions (or metal salts) are reduced inside the polyimide precursor resin to precipitate metal fine particles. It is easy to adjust the content of the metal compound, and it is easy to adjust the content of the metal fine particles to be dispersed in the polyimide resin. Accordingly, it is relatively easy to include metal fine particles having an average particle diameter in the range of 3 nm to 25 nm, the volume fraction of the metal fine particles is in the range of 0.05 to 1%, and the thickness is in the range of 300 nm to 1 μm. The metal fine particle composite can be produced. In addition, since the reduction treatment is performed by heating, the metal fine particles can be dispersed in the matrix resin while maintaining a certain inter-particle distance using the thermal diffusion of the deposited metal fine particles. Further, metal fine particles dispersed at a certain inter-particle distance are present from the surface layer portion of the matrix resin.

Since the metal fine particle composite produced by the method of the present invention has the above-mentioned structural characteristics, the field uses a localized surface plasmon effect such as a pressure sensor, for example, an electromagnetic shielding material or a magnetic noise absorbing material. It can be applied to various industrial fields such as high thermal conductive resin materials. In particular, in the metal fine particle composite obtained by the method of the present invention, the polyimide resin layer has a sufficient film thickness of 300 nm to 1 μm, while the average particle diameter of the metal fine particles is 3 nm to 25 nm, which is relative to the film thickness. And the volume fraction of the metal fine particles is 0.05 to 1% with respect to the metal fine particle composite, and can be preferably applied to the use of a pressure sensor utilizing localized surface plasmon resonance. In other words, since the thickness of the polyimide resin layer is sufficiently large with respect to the average particle diameter and interparticle distance of the metal fine particles, it is possible to increase the width of the elastic deformation at the time of pressurization. The moving distance can also be increased. Therefore, it is possible to widen a detection margin as a pressure sensor and to improve detection accuracy. In addition, since the average particle diameter range of the metal fine particles is as narrow as 3 nm to 25 nm, the dispersion of the particle diameter is small, and at the time of pressurization, sharp absorption is obtained by localized surface plasmon resonance, so that highly sensitive detection is possible. . Therefore, it is expected that the use pressure range as a pressure sensor is wide and high detection sensitivity and measurement accuracy are obtained.

[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail. In the following description, differences from the first embodiment will be mainly described. In the method for producing the metal fine particle composite according to the second embodiment of the present invention, the metal fine particles having an average particle diameter in the range of 3 nm to 30 nm are not in contact with each other in the polyimide resin. The metal fine particles having the larger particle diameter are dispersed independently of each other (preferably completely independently) at intervals equal to or larger than the particle diameter, and the volume fraction of the metal fine particles is 0. 0 relative to the metal fine particle composite. A metal fine particle composite in the range of 2% to 5% is manufactured, and includes the following steps a and b. As the polyimide resin and the polyimide precursor resin in the method for producing the metal fine particle composite of the present embodiment, those described in the first embodiment can be used.

[Step a: Coating film forming step]
In the method for producing a metal fine particle composite of the present embodiment, a coating film is formed by applying a coating liquid containing a polyimide precursor resin and a metal compound onto a substrate and drying. Step a in the present embodiment can be performed in the same manner as step a in the first embodiment, except that the metal content in the coating solution for forming the coating film is different.

The coating solution used in step a of the present embodiment has a metal content derived from the metal compound in the range of 10 μg / cm ² to 50 μg / cm ² , preferably in the range of 10 μg / cm ² to 40 μg / cm ² . Of these, it is preferably applied onto the substrate so as to be in the range of 10 μg / cm ² to 30 μg / cm ² . For the amount of metal per unit area of the coating film obtained by coating, the content of the metal in the coating solution is determined in advance, and a method of controlling by the film thickness of the coating film, or the film thickness of the coating film in advance There is a method of determining and controlling by the metal content in the coating solution. The thickness of the coating film is such that the thickness after drying is in the range of 500 nm to 1.7 μm, preferably in the range of 1 μm to 1.7 μm, and the thickness of the polyimide resin layer after imidization is 300 nm. It is set within the range of ˜1 μm, preferably within the range of 600 nm to 1 μm. If the thickness of the polyimide resin layer after imidization is less than 300 nm, the metal fine particles tend to agglomerate. On the other hand, if the thickness exceeds 1 μm, the metal fine particles formed in the polyimide resin layer tend to be small. The average particle diameter of the metal fine particles tends to vary between the surface layer portion and the deep portion of the resin layer.

In addition, in order to control the average particle diameter and the interparticle distance of the metal fine particles, the range of the metal content in the coating film (10 μg / cm ² to 50 μg / cm ² ) and the polyimide resin layer after imidization In addition, after satisfying the conditions of the thickness range (300 nm to 1 μm), the content A [μg / cm ² ] of the metal content in the coating film and the thickness B [nm] of the polyimide resin layer after imidization It is more preferable to satisfy the following formula.
2 ≦ (A / B) × 100 ≦ 12 (ii)

[Step b: Heat treatment step]
In step b, the coating film obtained as described above is heat treated in the range of 160 to 450 ° C., preferably in the range of 200 to 400 ° C., more preferably in the range of 300 to 400 ° C. Ions (or metal salts) are reduced to deposit particulate metal that becomes metal fine particles, and dispersed in the coating film. Also, by this heat treatment, the polyimide precursor resin in the coating film is imidized to form a polyimide resin layer having a thickness in the range of 300 nm to 1 μm and an elastic modulus in the range of 3 GPa to 10 GPa. Step b in the present embodiment can be performed in the same manner as step b in the first embodiment, except as described below.

The modulus of elasticity of the polyimide precursor resin / polyimide resin during the heat treatment in step b (that is, the modulus of elasticity when heated within the range of 160 to 450 ° C.) affects the thermal diffusivity of the metal fine particles. Therefore, the elastic modulus of the polyimide precursor resin / polyimide resin in the heat treatment process is adjusted for the purpose of appropriately promoting the thermal diffusion of the metal fine particles. In the method of this embodiment, the modulus of elasticity of the polyimide precursor resin / polyimide resin is such that the modulus of elasticity of the cured polyimide resin is, for example, in the range of 3 GPa to 10 GPa, preferably in the range of 4 GPa to 10 GPa. Adjust. If the elastic modulus of the cured polyimide resin is less than 3 GPa, it becomes difficult to control the dispersion of the metal fine particles during the heat treatment in step b, and the metal fine particles tend to aggregate. On the other hand, when the elastic modulus of the cured polyimide resin exceeds 10 GPa, the dispersion of the metal fine particles is remarkably suppressed, so that the generated metal fine particles become excessively small, for example, for applications such as a sensor using localized surface plasmon resonance. When used, the sensitivity tends to decrease, and the toughness of the polyimide resin as the matrix decreases, and the material tends to be extremely brittle.

In the present embodiment, the elastic modulus of the cured polyimide resin is defined, but the elastic modulus is related to the elastic modulus of the polyimide precursor resin / polyimide resin in the heat treatment process of step b, and the heat treatment process. This is because it becomes an index reflecting the elastic modulus. That is, the higher the elastic modulus of the cured polyimide resin, the higher the elastic modulus of the polyimide precursor resin / polyimide resin in the heat treatment process of step b, and the lower the elastic modulus of the cured polyimide resin, the polyimide in the heat treatment process of step b. The elastic modulus of the precursor resin / polyimide resin is low. Therefore, the thermal diffusion of the metal fine particles can be controlled by controlling the elastic modulus of the cured polyimide resin.

Also, the polyimide precursor resin in the coating film is imidized by this heat treatment, and the content of the metal fine particles is in the range of 10 μg / cm ² to 50 μg / cm ² , preferably in the range of 10 μg / cm ² to 40 μg / cm ² . Among them, a polyimide resin layer having a thickness in the range of 10 μg / cm ² to 30 μg / cm ² and a thickness in the range of 300 nm to 1 μm, preferably in the range of 600 nm to 1 μm is formed.

The average particle diameter and interparticle distance of the metal fine particles are: i) the heat treatment temperature in the heat treatment step, ii) the content of metal ions (or metal salts) contained in the coating film, and iii) the polyimide resin layer finally formed It can be controlled by the thickness and iv) the elastic modulus of the polyimide precursor resin / polyimide resin during the heat treatment. In the case where the heat treatment temperature is constant and the absolute amount of metal ions (or metal salts) contained in the coating film is different, or the absolute amount of metal ions (or metal salts) contained in the coating film is different. In the case where the thickness of the coating film is different even if it is constant, it has been found that the particle diameters of the deposited metal fine particles are different. In addition, when the heat treatment is performed without controlling the heat treatment temperature, the content of metal ions (or metal salts) contained in the coating film, and the thickness of the polyimide resin layer finally formed, the interparticle distance is reduced. It has also been found that metal fine particles aggregate on the surface of the polyimide resin layer to form islands. Furthermore, the modulus of elasticity of the polyimide precursor resin / polyimide resin during the heat treatment in step b affects the thermal diffusibility of the metal fine particles, and the softer the polyimide precursor resin / polyimide resin at the heat treatment temperature, It has also been found that heat diffusion is more likely to proceed, and conversely, the harder the polyimide precursor resin / polyimide resin, the more difficult the heat diffusion of the metal fine particles.

Based on the above knowledge, it has been found that the average particle diameter and the interparticle distance of the metal fine particles can be controlled by controlling the above conditions i) to iv). That is, by controlling the conditions i) to iv), the average particle diameter of the metal fine particles is controlled within the range of 3 nm to 30 nm, and the metal fine particles thus controlled have their respective particle spacings (interparticle distances). L is the particle size of the larger metal particles in neighboring metal fine particles (D _L) or higher, i.e., it will be present in relation L ≧ D _L. Metal particle composite of the present embodiment, due to the provision of the requirements of step a and step b, the deposited metal particles thermal diffusion is facilitated, those over the particle diameter D _L of the larger in the metal particles adjacent It will be in the state disperse | distributed in the polyimide resin by the distance L between particles. Although there is no particular problem even if the interparticle distance L is large, the interparticle distance L in the metal fine particles that are dispersed using thermal diffusion is closely related to the particle diameter D of the metal fine particles and the volume fraction of the metal fine particles. Therefore, the upper limit of the interparticle distance L is preferably controlled by the lower limit value of the volume fraction of the metal fine particles.

In the present embodiment, the volume fraction of the metal fine particles is in the range of 0.2 to 5%, preferably in the range of 0.5 to 3% with respect to the metal fine particle composite. By setting the volume fraction within the above range, the interparticle distance L of the metal fine particles can be controlled. The volume fraction of the metal fine particles can be adjusted mainly by the content of the metal in the coating solution in step a.

In addition, in the manufacturing method of this Embodiment, arbitrary processes, such as an etching process, can also be performed other than the said process a and process b, for example.

As described above, according to the method for producing the metal fine particle composite of the present embodiment, the metal precursor (or metal salt) is reduced inside the polyimide precursor resin to precipitate the metal fine particles. It is easy to adjust the content of the metal compound therein, and it is easy to adjust the content of the metal fine particles dispersed in the polyimide resin. Accordingly, it is relatively easy to include metal fine particles having an average particle diameter in the range of 3 nm to 30 nm, the volume fraction of the metal fine particles is in the range of 0.2% to 5%, and the thickness is 300 nm to 1 μm. Metal fine particle composites within the range can be produced. In addition, since the reduction treatment is performed by heating, the metal fine particles can be dispersed in the matrix resin while maintaining a certain inter-particle distance using the thermal diffusion of the deposited metal fine particles. Further, metal fine particles dispersed at a certain inter-particle distance are present from the surface layer portion of the matrix resin.

Moreover, in the method for producing a metal fine particle composite according to the present embodiment, the imidization of the polyimide precursor resin can be completed using the heat used in the reduction treatment, so that the production process can be simplified.

Since the metal fine particle composite produced by the method of the present embodiment has the structural characteristics described above, the field uses a localized surface plasmon effect such as a pressure sensor, for example, an electromagnetic shielding material or a magnetic noise. It can be applied to various industrial fields such as absorbent materials and high thermal conductive resin materials. In particular, in the metal fine particle composite obtained by the method of the present embodiment, the polyimide resin layer has a sufficient film thickness of 300 nm to 1 μm, while the average particle diameter of the metal fine particles is 3 nm to 30 nm, compared with the film thickness. And the volume fraction of the metal fine particles is 0.2% or more and 5% or less with respect to the metal fine particle composite, and can be preferably applied to the use of a pressure sensor using localized surface plasmon resonance. . In other words, since the thickness of the polyimide resin layer is sufficiently large with respect to the average particle diameter and interparticle distance of the metal fine particles, it is possible to increase the width of the elastic deformation at the time of pressurization. The moving distance can also be increased. Therefore, it is possible to widen a detection margin as a pressure sensor and to improve detection accuracy. In addition, since the average particle diameter range of the metal fine particles is as narrow as 3 nm to 30 nm, the particle diameter variation is small, and at the time of pressurization, sharp absorption is obtained by localized surface plasmon resonance, so that highly sensitive detection is possible. . Therefore, it is expected that the use pressure range as a pressure sensor is wide and high detection sensitivity and measurement accuracy are obtained.

Other configurations and effects in the manufacturing method of the metal fine particle composite of the present embodiment are the same as those of the first embodiment.

[Third Embodiment]
Next, embodiments of the present invention will be described in detail. In the following description, differences from the first embodiment will be mainly described. In the method for producing a metal fine particle composite according to the third embodiment of the present invention, metal fine particles having an average particle diameter in the range of 3 nm to 30 nm are not in contact with each other in the polyimide resin. The metal fine particles having the larger particle diameter are dispersed independently of each other (preferably completely independently) at intervals equal to or larger than the particle diameter, and the volume fraction of the metal fine particles is 0. 0 relative to the metal fine particle composite. A metal fine particle composite in the range of 5% or more and 5% or less is manufactured, and includes the following steps a and b. As the polyimide resin and the polyimide precursor resin in the method for producing the metal fine particle composite of the present embodiment, those described in the first embodiment can be used.

The coating liquid used in step a of the present embodiment has a metal content derived from the metal compound in the range of 5 μg / cm ² to 10 μg / cm ² , preferably in the range of 5 μg / cm ² to 9 μg / cm ² . Of these, it is preferably applied onto the substrate so as to be in the range of 5 μg / cm ² to 8 μg / cm ² . For the amount of metal per unit area of the coating film obtained by coating, the content of the metal in the coating solution is determined in advance, and a method of controlling by the film thickness of the coating film, or the film thickness of the coating film in advance There is a method of determining and controlling by the metal content in the coating solution. The thickness of the coating film is such that the thickness after drying is in the range of 150 nm to 500 nm, preferably in the range of 200 nm to 500 nm, and the thickness of the polyimide resin layer after imidization is in the range of 100 nm to 300 nm. The thickness is preferably in the range of 150 nm to 300 nm. If the thickness of the polyimide resin layer after imidization is less than 100 nm, the metal fine particles tend to agglomerate. On the other hand, if the thickness exceeds 300 nm, the metal fine particles formed in the polyimide resin layer tend to be small. The average particle diameter of the metal fine particles tends to vary between the surface layer portion and the deep portion of the resin layer.

In addition, in order to control the average particle size and the interparticle distance of the metal fine particles, the range of the metal content in the coating film (5 μg / cm ² to 10 μg / cm ² ) and the polyimide resin layer after imidization In addition, the metal content in the coating film A [μg / cm ² ] and the thickness B [nm] of the polyimide resin layer after imidization are satisfied. It is more preferable to satisfy the following formula.
2 ≦ (A / B) × 100 ≦ 8 (iii)

[Step b: Heat treatment step]
In step b, the coating film obtained as described above is heat treated in the range of 160 to 450 ° C., preferably in the range of 200 to 400 ° C., more preferably in the range of 300 to 400 ° C. Ions (or metal salts) are reduced to deposit particulate metal that becomes metal fine particles, and dispersed in the coating film. Also, by this heat treatment, the polyimide precursor resin in the coating film is imidized to form a polyimide resin layer having a thickness in the range of 100 nm to 300 nm and an elastic modulus in the range of 5 MPa to 10 GPa. Step b in the present embodiment can be performed in the same manner as step b in the first embodiment, except as described below.

The modulus of elasticity of the polyimide precursor resin / polyimide resin during the heat treatment in step b (that is, the modulus of elasticity when heated within the range of 160 to 450 ° C.) affects the thermal diffusivity of the metal fine particles. Therefore, the elastic modulus of the polyimide precursor resin / polyimide resin during the heat treatment is adjusted for the purpose of appropriately promoting the thermal diffusion of the metal fine particles. In the method of the present embodiment, the modulus of elasticity of the polyimide precursor resin / polyimide resin is such that the modulus of elasticity of the cured polyimide resin is, for example, in the range of 5 MPa to 10 GPa, preferably in the range of 8 MPa to 10 GPa. Adjust. When the elastic modulus of the cured polyimide resin is less than 5 MPa, it becomes difficult to control the dispersion of the metal fine particles during the heat treatment in the step b, and the metal fine particles tend to aggregate. On the other hand, when the elastic modulus of the cured polyimide resin exceeds 10 GPa, the dispersion of the metal fine particles is remarkably suppressed, so that the generated metal fine particles become excessively small, for example, for applications such as a sensor using localized surface plasmon resonance. When used, the sensitivity tends to decrease, and the toughness of the polyimide resin as the matrix decreases, and the material tends to be extremely brittle.

Also, the polyimide precursor resin in the coating film is imidized by this heat treatment, and the content of the metal fine particles is in the range of 5 μg / cm ² to 10 μg / cm ² , preferably in the range of 5 μg / cm ² to 9 μg / cm ² . Among them, a polyimide resin layer having a thickness in the range of 5 μg / cm ² to 8 μg / cm ² and a thickness in the range of 100 nm to 300 nm, preferably in the range of 150 nm to 300 nm is formed.

In the present embodiment, the volume fraction of the metal fine particles is in the range of 0.5 to 5%, preferably in the range of 1 to 3% with respect to the metal fine particle composite. By setting the volume fraction within the above range, the interparticle distance L of the metal fine particles can be controlled. The volume fraction of the metal fine particles can be adjusted mainly by the content of the metal in the coating solution in step a.

As described above, according to the method for producing the metal fine particle composite of the present embodiment, the metal precursor (or metal salt) is reduced inside the polyimide precursor resin to precipitate the metal fine particles. It is easy to adjust the content of the metal compound therein, and it is easy to adjust the content of the metal fine particles dispersed in the polyimide resin. Accordingly, it is relatively easy to include metal fine particles having an average particle diameter in the range of 3 nm to 30 nm, the volume fraction of the metal fine particles is in the range of 0.5 to 5%, and the thickness is in the range of 100 nm to 300 nm. The metal fine particle composite can be produced. In addition, since the reduction treatment is performed by heating, the metal fine particles can be dispersed in the matrix resin while maintaining a certain inter-particle distance using the thermal diffusion of the deposited metal fine particles. Further, metal fine particles dispersed at a certain inter-particle distance are present from the surface layer portion of the matrix resin.

Since the metal fine particle composite produced by the method of the present embodiment has the structural characteristics described above, the field uses a localized surface plasmon effect such as a pressure sensor. It can be applied to various industrial fields such as noise absorbers and high thermal conductive resin materials. In particular, in the metal fine particle composite obtained by the method of the present embodiment, the polyimide resin layer has a sufficient film thickness of 100 nm to 300 nm, while the average particle diameter of the metal fine particles is 3 nm to 30 nm, compared with the film thickness. And the volume fraction of the metal fine particles is 0.5 to 5% with respect to the metal fine particle composite, so that it can be preferably applied to the use of a pressure sensor utilizing localized surface plasmon resonance. In other words, since the thickness of the polyimide resin layer is sufficiently large with respect to the average particle diameter and interparticle distance of the metal fine particles, it is possible to increase the width of the elastic deformation at the time of pressurization. The moving distance can also be increased. Therefore, it is possible to widen a detection margin as a pressure sensor and to improve detection accuracy. In addition, since the average particle diameter range of the metal fine particles is as narrow as 3 nm to 30 nm, the particle diameter variation is small, and at the time of pressurization, sharp absorption is obtained by localized surface plasmon resonance, so that highly sensitive detection is possible. . Therefore, it is expected that the use pressure range as a pressure sensor is wide and high detection sensitivity and measurement accuracy are obtained. In addition, the metal fine particle composite obtained by the method of the present embodiment can be thinned to a thickness of 100 nm to 300 nm for the polyimide resin layer, and thus is suitable for applications for sensing subtle changes in the surface layer portion of the metal fine particle composite. Utilizing such properties, for example, by etching the surface layer portion of the metal fine particle composite, and exposing a part of the metal fine particles on the surface layer portion of the composite to the surface from the matrix, the change of the external environment can be controlled. Applications such as being able to be used advantageously as a sensor substrate for sensing can be expected.

[Fourth Embodiment]
Next, embodiments of the present invention will be described in detail. In the following description, differences from the first embodiment will be mainly described. In the method for producing a metal fine particle composite according to one embodiment of the present invention, the particle diameters of adjacent metal fine particles are not contacted with each other in the polyimide resin without the metal fine particles having an average particle diameter in the range of 5 nm to 35 nm. Are dispersed independently of each other (preferably completely independently) at intervals equal to or larger than the particle diameter of the larger metal fine particles, and the volume fraction of the metal fine particles is 1% or more to the metal fine particle composite. % Of the metal fine particle composite in the range of not more than%, and includes the following steps a and b. As the polyimide resin and the polyimide precursor resin in the method for producing the metal fine particle composite of the present embodiment, those described in the first embodiment can be used.

Coating liquid used in step a of the present embodiment, the range content is ^{10μg / cm 2 ~ 30μg / cm} 2 of metal component derived from the metal compound, ranges preferably from ^{10μg / cm 2 ~ 27μg / cm} 2 Of these, it is preferably applied on the substrate so as to be in the range of 10 μg / cm ² to 25 μg / cm ² . For the amount of metal per unit area of the coating film obtained by coating, the content of the metal in the coating solution is determined in advance, and a method of controlling by the film thickness of the coating film, or the film thickness of the coating film in advance There is a method of determining and controlling by the metal content in the coating solution. The thickness of the coating film is such that the thickness after drying is in the range of 150 nm to 500 nm, preferably in the range of 200 nm to 500 nm, and the thickness of the polyimide resin layer after imidization is in the range of 100 nm to 300 nm. The thickness is preferably in the range of 150 nm to 300 nm. If the thickness of the polyimide resin layer after imidization is less than 100 nm, the metal fine particles tend to agglomerate. On the other hand, if the thickness exceeds 300 nm, the metal fine particles formed in the polyimide resin layer tend to be small. The average particle diameter of the metal fine particles tends to vary between the surface layer portion and the deep portion of the resin layer.

In addition, in order to control the average particle size and the interparticle distance of the metal fine particles, the content range (10 μg / cm ² to 30 μg / cm ² ) of the metal content in the coating film and the polyimide resin layer after imidization In addition, the metal content in the coating film A [μg / cm ² ] and the thickness B [nm] of the polyimide resin layer after imidization are satisfied. It is more preferable that the relationship between and satisfies the following formula.
5 ≦ (A / B) × 100 ≦ 25 (iv)

[Step b: Heat treatment step]
In step b, the coating film obtained as described above is heat treated in the range of 160 to 450 ° C., preferably in the range of 200 to 400 ° C., more preferably in the range of 300 to 400 ° C. Ions (or metal salts) are reduced to deposit particulate metal that becomes metal fine particles, and dispersed in the coating film. Also, by this heat treatment, the polyimide precursor resin in the coating film is imidized to form a polyimide resin layer having a thickness in the range of 100 nm to 300 nm and an elastic modulus in the range of 0.5 GPa to 10 GPa. Step b in the present embodiment can be performed in the same manner as step b in the first embodiment, except as described below.

Further, the modulus of elasticity of the polyimide precursor resin / polyimide resin (that is, the modulus of elasticity when heated within the range of 160 to 450 ° C.) during the heat treatment in step b affects the thermal diffusivity of the metal fine particles. Therefore, the elastic modulus of the polyimide precursor resin / polyimide resin during the heat treatment is adjusted for the purpose of appropriately promoting the thermal diffusion of the metal fine particles. In the method of the present embodiment, the polyimide precursor resin / polyimide is such that the elastic modulus of the cured polyimide resin is, for example, in the range of 0.5 GPa to 10 GPa, preferably in the range of 0.6 GPa to 10 GPa. Adjust the elastic modulus of the resin. If the elastic modulus of the cured polyimide resin is less than 0.5 GPa, it becomes difficult to control the dispersion of the metal fine particles during the heat treatment in step b, and the metal fine particles tend to aggregate. On the other hand, when the elastic modulus of the cured polyimide resin exceeds 10 GPa, the dispersion of the metal fine particles is remarkably suppressed, so that the generated metal fine particles become excessively small, for example, for applications such as a sensor using localized surface plasmon resonance. When used, the sensitivity tends to decrease, and the toughness of the polyimide resin as the matrix decreases, and the material tends to be extremely brittle.

Further, by imidizing a polyimide precursor resin in the coating film by the heat treatment in the range content is ^{10μg / cm 2 ~ 30μg / cm} 2 of metal fine particles, ranging preferably from ^{10μg / cm 2 ~ 27μg / cm} 2 Among them, a polyimide resin layer having a thickness in the range of 10 μg / cm ² to 25 μg / cm ² and a thickness in the range of 100 nm to 300 nm, preferably in the range of 150 nm to 300 nm is formed.

As described above, the average particle diameter and the interparticle distance of the metal fine particles are i) the heat treatment temperature in the heat treatment step, ii) the content of metal ions (or metal salts) contained in the coating film, and iii) finally formed. It can be controlled by the thickness of the polyimide resin layer and iv) the hardness of the polyimide precursor resin / polyimide resin during the heat treatment. In the case where the heat treatment temperature is constant and the absolute amount of metal ions (or metal salts) contained in the coating film is different, or the absolute amount of metal ions (or metal salts) contained in the coating film is different. In the case where the thickness of the coating film is different even if it is constant, it has been found that the particle diameters of the deposited metal fine particles are different. In addition, when the heat treatment is performed without controlling the heat treatment temperature, the content of metal ions (or metal salts) contained in the coating film, and the thickness of the polyimide resin layer finally formed, the interparticle distance is reduced. It has also been found that metal fine particles aggregate on the surface of the polyimide resin layer to form islands. Furthermore, the modulus of elasticity of the polyimide precursor resin / polyimide resin during the heat treatment in step b affects the thermal diffusibility of the metal fine particles, and the softer the polyimide precursor resin / polyimide resin at the heat treatment temperature, It has also been found that heat diffusion is more likely to proceed, and conversely, the harder the polyimide precursor resin / polyimide resin, the more difficult the heat diffusion of the metal fine particles.

Based on the above knowledge, it has been found that the average particle diameter and the interparticle distance of the metal fine particles can be controlled by controlling the above conditions i) to iv). That is, by controlling the conditions i) to iv), the average particle diameter of the metal fine particles is controlled within the range of 5 nm to 35 nm, and the metal fine particles thus controlled have their respective particle spacings (interparticle distances). L is the particle size of the larger metal particles in neighboring metal fine particles (D _L) or higher, i.e., it will be present in relation L ≧ D _L. Metal particle composite of the present embodiment, due to the provision of the requirements of step a and step b, the deposited metal particles thermal diffusion is facilitated, those over the particle diameter D _L of the larger in the metal particles adjacent It will be in the state disperse | distributed in the polyimide resin by the distance L between particles. Although there is no particular problem even if the interparticle distance L is large, each interparticle distance L in the metal fine particles that are dispersed by utilizing thermal diffusion is determined based on the particle diameter D of the metal fine particles and the volume fraction of the metal fine particles described later. Therefore, the upper limit of the interparticle distance L is preferably controlled by the lower limit value of the volume fraction of the metal fine particles.

In the present embodiment, the volume fraction of the metal fine particles is in the range of 1 to 15%, preferably in the range of 2 to 10% with respect to the metal fine particle composite. By setting the volume fraction within the above range, the interparticle distance L of the metal fine particles can be controlled. The volume fraction of the metal fine particles can be adjusted mainly by the content of the metal in the coating solution in step a.

As described above, according to the method for producing the metal fine particle composite of the present embodiment, the metal precursor (or metal salt) is reduced inside the polyimide precursor resin to precipitate the metal fine particles. It is easy to adjust the content of the metal compound therein, and it is easy to adjust the content of the metal fine particles dispersed in the polyimide resin. Accordingly, it is relatively easy to include metal fine particles having an average particle diameter in the range of 5 nm to 35 nm, a volume fraction of the metal fine particles in the range of 1 to 15%, and a thickness in the range of 100 nm to 300 nm. Fine particle composites can be produced. In addition, since the reduction treatment is performed by heating, the metal fine particles can be dispersed in the matrix resin while maintaining a certain inter-particle distance using the thermal diffusion of the deposited metal fine particles. Further, metal fine particles dispersed at a certain inter-particle distance are present from the surface layer portion of the matrix resin.

Since the metal fine particle composite produced by the method of the present embodiment has the structural characteristics described above, the field uses a localized surface plasmon effect such as a pressure sensor. It can be applied to various industrial fields such as noise absorbers and high thermal conductive resin materials. In particular, in the metal fine particle composite obtained by the method of the present embodiment, the polyimide resin layer has a sufficient film thickness of 100 nm to 300 nm, while the average particle diameter of the metal fine particles is 5 nm to 35 nm, compared with the film thickness. And the volume fraction of the metal fine particles is 1 to 15% with respect to the metal fine particle composite, so that it can be preferably applied to the use of a pressure sensor utilizing localized surface plasmon resonance. In other words, since the thickness of the polyimide resin layer is sufficiently large with respect to the average particle diameter and interparticle distance of the metal fine particles, it is possible to increase the width of the elastic deformation at the time of pressurization. The moving distance can also be increased. Therefore, it is possible to widen a detection margin as a pressure sensor and to improve detection accuracy. Moreover, since the average particle diameter range of the metal fine particles is as narrow as 5 nm to 35 nm, the dispersion of the particle diameter is small, and at the time of pressurization, sharp absorption is obtained by localized surface plasmon resonance, so that highly sensitive detection is possible. . Therefore, it is expected that the use pressure range as a pressure sensor is wide and high detection sensitivity and measurement accuracy are obtained. In addition, the metal fine particle composite obtained by the method of the present embodiment can be thinned to a thickness of 100 nm to 300 nm for the polyimide resin layer, and thus is suitable for applications for sensing subtle changes in the surface layer portion of the metal fine particle composite. Utilizing such properties, for example, by etching the surface layer portion of the metal fine particle composite, and exposing a part of the metal fine particles on the surface layer portion of the composite to the surface from the matrix, the change of the external environment can be controlled. Applications such as being able to be used advantageously as a sensor substrate for sensing can be expected.

Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In the examples of the present invention, various measurements and evaluations are as follows unless otherwise specified.

[Measurement of average particle diameter of metal fine particles]
The average particle diameter of the metal fine particles was measured by preparing a cross section of the sample using a microtome (produced by Leica Co., Ltd., Ultra Cut UTC Ultra Microtome), and transmitting a transmission electron microscope (TEM; JEOL Co., Ltd., JEM- 2000EX). In addition, since it was difficult to observe the sample produced on the glass substrate by said method, it observed using what was produced on the polyimide film on the same conditions. The average particle diameter of the metal fine particles was the area average diameter.

[Measurement of absorption spectrum of sample]
The absorption spectrum of the prepared sample was observed by ultraviolet / visible / near infrared spectroscopy (manufactured by JASCO Corporation, UV-vis U-4000).

[Measurement of light transmittance]
The light transmittance was measured using ultraviolet / visible spectroscopic analysis (manufactured by JASCO Corporation, UV-vis V-550).

[Measurement of elastic modulus]
Using a rheometrics RSA II, a polyimide film cut to a size of 5 × 33 mm under the conditions of a heating rate of 10 ° C./min, a temperature range of 40 ° C. to 450 ° C., a frequency of 1 Hz, and a strain of 0.001 The viscoelastic properties were measured, and the elastic modulus of polyimide at each temperature was determined.

Synthesis example 1
In a 1000 ml separable flask, 425 g of N, N-dimethylacetamide (DMAc), 31.8 g of 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB) and 4.9 g of 1 , 3-Bis (4-aminophenoxy) benzene (APB) was stirred at room temperature for 30 minutes. Thereafter, 28.6 g of pyromellitic dianhydride (PMDA) and 9.6 g of 3,4,3 ′, 4′-biphenyltetracarboxylic dianhydride (BPDA) were added, and 3% at room temperature under a nitrogen atmosphere. the mixture was subjected to polymerization reaction continued time stirring to obtain a viscous polyimide precursor resin solution S _1. The resulting viscosity of the polyimide precursor resin solution _{S 1} is, E-type viscometer (manufactured by Brookfield, DV-II + Pro CP type) results as measured by, was 28,000 centipoise (25 ° C.).

The resulting polyimide precursor resin solution S ₁ was applied on a stainless steel substrate, and dried for 3 minutes at 130 ° C., to complete the over 15 minutes allowed to warm to 360 ° C. imidization, the stainless steel substrate A laminated polyimide film was obtained. The polyimide film was peeled from the stainless steel substrate, to obtain a polyimide film P ₁ of 25μm thickness. The light transmittances of the film at wavelengths of 400 nm, 500 nm, and 600 nm were 0%, 70.5%, and 82%, respectively. Moreover, as a result of measuring the elasticity modulus in temperature 200 degreeC, 300 degreeC, and 400 degreeC about this film, they were 3 GPa, 2 GPa, and 0.6 GPa, respectively.

Synthesis example 2
In a 500 ml separable flask, 15.24 g of 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl (TFMB) 47.6 mmol was dissolved in 170 g of DMAc with stirring. Next, 14.76 g of 4,4′-oxydiphthalic anhydride (ODPA) 47.6 mmol was added to the solution under a nitrogen stream, and the polymerization reaction was continued at room temperature for 4 hours to obtain a colorless viscous liquid. to obtain a polyimide precursor resin solution S _2. The resulting viscosity of the polyimide precursor resin solution _{S 2} is, E-type viscometer (manufactured by Brookfield, DV-II + Pro CP type) results as measured by, was 3251 centipoise (25 ° C.). The weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC; manufactured by Tosoh Corporation, HLC-8220 GPC), and was Mw = 163,900.

The resulting polyimide precursor resin solution S _2, coated on the stainless steel substrate, and dried for 3 minutes at 130 ° C., to complete the over 15 minutes allowed to warm to 360 ° C. imidization, the stainless steel substrate A laminated polyimide film was obtained. The polyimide film was peeled from the stainless steel substrate, to obtain a polyimide film P ₂ of 10μm in thickness. The film had a light transmittance of 95% and a visible light average transmittance of 96% at a wavelength of 400 nm. Moreover, as a result of measuring the elasticity modulus in temperature 200 degreeC, 300 degreeC, and 400 degreeC about this film, they were 0.2 GPa, 0.01 GPa, and 0.001 GPa, respectively.

Synthesis example 3
In a 1000 ml separable flask, 6.4 g of N, N-dimethylacetamide (DMAc) and 36.4 g of 1,3-bis (4-aminophenoxy) benzene (APB) were stirred at room temperature for 30 minutes. Thereafter, 11.1 g of pyromellitic dianhydride (PMDA) and 27.4 g of 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride (DSDA) were added, and at room temperature under a nitrogen atmosphere. stirred continuously for 3 hours and polymerization was carried out to obtain a viscous polyimide precursor resin solution S _3. The resulting viscosity of the polyimide precursor resin solution _{S 3} is, E-type viscometer (manufactured by Brookfield, DV-II + Pro CP type) results as measured by, was 2,500 centipoise (25 ° C.).

The polyimide precursor resin solution S ₃ obtained was coated on a stainless steel substrate, and dried for 3 minutes at 130 ° C., to complete the over 15 minutes allowed to warm to 360 ° C. imidization, the stainless steel substrate A laminated polyimide film was obtained. The polyimide film was peeled from the stainless steel substrate, to obtain a polyimide film P ₃ of 25μm thickness. The light transmittances of the film at wavelengths of 400 nm, 500 nm, and 600 nm were 0%, 60%, and 72%, respectively. Moreover, as a result of measuring the elasticity modulus in temperature 200 degreeC, 300 degreeC, and 400 degreeC about this film, they were 1 GPa, 0.08 GPa, and 0.008 GPa, respectively.

Production Example 1
A test piece of alkali-free glass (Asahi Glass Co., Ltd., AN-100) 10 cm × 10 cm (thickness 0.7 mm) was treated with a 5N sodium hydroxide aqueous solution at 50 ° C. for 5 minutes. Next, the glass substrate of the test piece was washed with pure water, dried, and then immersed in a 1 wt% aqueous solution of 3-aminopropyltrimethoxysilane (hereinafter abbreviated as “γ-APS”). The glass substrate was taken out from the γ-APS aqueous solution, dried, and heated at 110 ° C. for 5 minutes to produce a glass substrate G1.

[Example 1-1]
0.191 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-1 having a thickness of about 1380 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-1 had a content per unit area of 8.19 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-1 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-1 (thickness: 828 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-1 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 10.6 nm, maximum particle size: 18.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-1; 0.5 %, Average value of interparticle distance; 39.4 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-1, an absorption peak having a peak top of 560 nm and a half width of 72 nm was observed.

[Example 1-2]
0.191 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-2 having a thickness of about 1473 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-2 had a gold content per unit area of 8.74 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-2 was heat-treated at 300 ° C. for 10 minutes in the air to produce a metal gold fine particle dispersed nanocomposite film 1-2 (thickness 884 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-2 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 12.2 nm, maximum particle size: 29.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-2: 0.5 %, Average value of interparticle distance; 45.3 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-2, an absorption peak having a peak top of 564 nm and a half-value width of 92 nm was observed.

[Example 1-3]
0.191 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-3 having a thickness of about 1440 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-3 had a gold content per unit area of 8.55 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-3 was heat-treated at 400 ° C. for 10 minutes in the air to produce a metal gold fine particle-dispersed nanocomposite film 1-3 (thickness: 865 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-3 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 15.0 nm, maximum particle size: 29.0 nm, minimum particle size: 6.0 nm, gold volume fraction in nanocomposite film 1-3: 0.5 %, Average value of interparticle distance; 55.7 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-3, an absorption peak having a peak top of 570 nm and a half-value width of 76 nm was observed.

[Example 1-4]
0.191 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-4 having a thickness of about 1370 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-4 had a content per unit area of gold of 7.98 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-4 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-4 (thickness 827 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-4 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 13.3 nm, maximum particle size; 22.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-4; 0.5 %, Average value of interparticle distance; 49.4 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-4, an absorption peak having a peak top of 560 nm and a half-value width of 80 nm was observed.

[Example 1-5]
0.191 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-5 having a thickness of about 1260 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-5 had a gold content per unit area of 7.29 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-5 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-5 (thickness: 755 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-5 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 17.4 nm, maximum particle size; 26.0 nm, minimum particle size: 7.0 nm, gold volume fraction in nanocomposite film 1-5; 0.5 %, Average value of interparticle distance; 64.6 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-5, an absorption peak having a peak top of 574 nm and a half-value width of 69 nm was observed.

[Example 1-6]
0.191 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-6 having a thickness of about 1220 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-6 had a gold content per unit area of 7.06 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-6 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-6 (thickness 730 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-6 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 19.8 nm, maximum particle size: 35.0 nm, minimum particle size: 10.0 nm, gold volume fraction in nanocomposite film 1-6; 0.5 %, Average value of interparticle distance; 73.5 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 1-6, an absorption peak having a peak top of 576 nm and a half-value width of 72 nm was observed.

[Example 1-7]
0.127 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-7 having a thickness of about 750 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-7 had a gold content per unit area of 4.45 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-7 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-7 (thickness 450 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-7 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 8.5 nm, maximum particle size: 11.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-7; 0.5 %, Average value of interparticle distance; 31.6 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-7, an absorption peak having a peak top of 546 nm and a half-value width of 83 nm was observed.

[Example 1-8]
0.127 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-8 having a thickness of about 770 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-8 had a gold content per unit area of 4.55 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-8 was heat-treated at 300 ° C. for 10 minutes in the air to produce a metal gold fine particle dispersed nanocomposite film 1-8 (thickness: 460 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-8 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 9.6 nm, maximum particle size: 17.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 1-8; 0.5 %, Average value of interparticle distance; 35.6 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-8, an absorption peak having a peak top of 560 nm and a half-value width of 77 nm was observed.

[Example 1-9]
0.127 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-9 having a thickness of about 760 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-9 had a gold content per unit area of 4.53 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-9 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-9 (thickness: 458 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-9 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 9.8 nm, maximum particle size: 19.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 1-9; 0.5 %, Average value of interparticle distance; 36.4 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-9, an absorption peak having a peak top of 560 nm and a half width of 69 nm was observed.

[Example 1-10]
0.127 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-10 having a thickness of about 732 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-10 had a gold content per unit area of 4.24 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-10 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-10 (thickness: 439 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-10 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 9.1 nm, maximum particle size; 14.0 nm, minimum particle size: 7.0 nm, gold volume fraction in nanocomposite film 1-10; 0.5 %, Average value of interparticle distance; 33.8 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-10, an absorption peak having a peak top of 542 nm and a half width of 71 nm was observed.

[Example 1-11]
0.127 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-11 having a thickness of about 730 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-11 had a gold content per unit area of 4.23 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-11 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-11 (thickness: 438 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-11 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 12.3 nm, maximum particle size: 22.0 nm, minimum particle size: 6.0 nm, gold volume fraction in nanocomposite film 1-11; 0.5 %, Average value of interparticle distance; 45.7 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-11, an absorption peak having a peak top of 550 nm and a half width of 65 nm was observed.

[Example 1-12]
0.127 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-12 having a film thickness of about 592 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-12 had a gold content per unit area of 3.43 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-12 was heat-treated at 400 ° C. for 10 minutes in the air to produce a metal gold fine particle dispersed nanocomposite film 1-12 (thickness: 355 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-12 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 12.4 nm, maximum particle size: 22.0 nm, minimum particle size: 8.0 nm, gold volume fraction in nanocomposite film 1-12; 0.5 %, Average value of interparticle distance; 46.0 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-12, an absorption peak having a peak top of 552 nm and a half width of 69 nm was observed.

[Example 1-13]
0.038 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added at room temperature for 15 minutes under a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-13 having a thickness of about 1430 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-13 had a gold content per unit area of 1.69 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-13 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-13 (thickness: 857 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-13 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 4.9 nm, maximum particle size: 8.0 nm, minimum particle size: 3.0 nm, gold volume fraction in nanocomposite film 1-13: 0.1%, interparticle distance Mean value; 34.6 nm.

[Example 1-14]
0.038 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added at room temperature for 15 minutes under a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-14 having a thickness of about 1455 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-14 had a gold content per unit area of 1.73 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-14 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-14 (thickness 873 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-14 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 6.1 nm, maximum particle size: 9.0 nm, minimum particle size: 3.0 nm, gold volume fraction in nanocomposite film 1-14: 0.1%, interparticle distance Mean value: 43.1 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-14, an absorption peak having a peak top of 558 nm and a half width of 60 nm was observed.

[Example 1-15]
0.038 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added at room temperature for 15 minutes under a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-15 having a thickness of about 1430 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-15 had a content of 1.69 μg / cm ² per unit area of gold. This gold complex-containing polyimide precursor resin film 1-15 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-15 (thickness 857 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-15 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 6.9 nm, maximum particle size: 9.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 1-15; 0.1%, interparticle distance Average value of 48.7 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-15, an absorption peak having a peak top of 552 nm and a half width of 68 nm was observed.

[Example 1-16]
To 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, 0.025 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-16 having a thickness of about 780 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-16 had a gold content per unit area of 0.93 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-16 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-16 (thickness: 470 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-16 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 4.8 nm, maximum particle size: 6.0 nm, minimum particle size: 3.0 nm, gold volume fraction in nanocomposite film 1-16: 0.1%, interparticle distance Mean value: 33.9 nm.

[Example 1-17]
To 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, 0.025 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-17 having a thickness of about 705 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-17 had a gold content per unit area of 0.84 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-17 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-17 (thickness 423 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-17 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 5.5 nm, maximum particle size: 7.0 nm, minimum particle size: 3.0 nm, gold volume fraction in nanocomposite film 1-17: 0.1%, interparticle distance Average value of 38.8 nm.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 1-17, an absorption peak having a peak top of 544 nm and a half width of 57 nm was observed.

[Example 1-18]
To 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, 0.025 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-18 having a thickness of about 690 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-18 had a gold content per unit area of 0.82 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-18 was heat-treated at 400 ° C. for 10 minutes in the air to produce a metal gold fine particle dispersed nanocomposite film 1-18 (thickness 414 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-18 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 6.6 nm, maximum particle size: 8.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-18; 0.1%, interparticle distance Average value of 46.6 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 1-18, an absorption peak having a peak top of 546 nm and a half-value width of 63 nm was observed.

[Example 1-19]
0.038 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-19 having a thickness of about 1510 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-19 had a gold content per unit area of 1.75 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-19 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-19 (thickness 905 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-19 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 5.6 nm, maximum particle size: 7.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-19: 0.1%, interparticle distance Mean value: 39.5 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 1-19, an absorption peak having a peak top of 544 nm and a half width of 56 nm was observed.

[Example 1-20]
0.038 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-20 having a thickness of about 1180 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-20 had a gold content per unit area of 1.37 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-20 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-20 (thickness 708 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-20 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 6.2 nm, maximum particle size: 8.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-20; 0.1%, interparticle distance Mean value: 43.8 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-20, an absorption peak having a peak top of 530 nm and a half width of 72 nm was observed.

[Example 1-21]
0.038 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-21 having a film thickness of about 1310 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin 1-21 had a gold content per unit area of 1.52 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-21 was heat-treated at 400 ° C. for 10 minutes in the air to produce a metal gold fine particle dispersed nanocomposite film 1-21 (thickness 788 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-21 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 7.2 nm, maximum particle size: 10.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-21; 0.1%, interparticle distance Average value: 50.8 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-21, an absorption peak having a peak top of 538 nm and a half width of 72 nm was observed.

[Example 1-22]
0.025 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-22 having a thickness of about 680 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin 1-22 had a gold content per unit area of 0.79 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-22 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-22 (thickness 410 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-22 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 5.2 nm, maximum particle size: 7.0 nm, minimum particle size: 3.0 nm, gold volume fraction in nanocomposite film 1-22: 0.1%, interparticle distance Average value of 36.7 nm.

[Example 1-23]
0.025 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-23 having a thickness of about 680 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin 1-23 had a gold content per unit area of 0.78 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-23 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-23 (thickness 406 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-23 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 5.8 nm, maximum particle size: 8.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-23: 0.1%, interparticle distance Average value: 40.9 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-23, an absorption peak having a peak top of 542 nm and a half width of 77 nm was observed.

[Example 1-24]
0.025 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-24 having a thickness of about 580 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin 1-24 had a gold content per unit area of 0.68 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-24 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-24 (thickness 350 nm) colored red. The metal gold fine particles formed in the nanocomposite film 1-24 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 6.6 nm, maximum particle size: 9.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 1-24: 0.1%, interparticle distance Average value of 46.6 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-24, an absorption peak having a peak top of 538 nm and a half width of 84 nm was observed.

[Example 1-25]
A silver complex was obtained by adding 0.118 g of silver nitrate dissolved in 13.33 g of DMAc to 6.67 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and stirring the mixture at room temperature for 15 minutes in a nitrogen atmosphere. A contained polyimide precursor resin solution was prepared. The obtained silver complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 The film was dried at a temperature of 10 ° C. for 10 minutes to form a silver complex-containing polyimide precursor resin film 1-25 having a thickness of about 667 nm on the glass substrate G1. The silver complex-containing polyimide precursor resin 1-25 had a silver content of 3.78 μg / cm ² per unit area. The silver complex-containing polyimide precursor resin film 1-25 was heat-treated at 300 ° C. for 10 minutes under vacuum to produce yellow-colored metallic silver fine particle dispersed nanocomposite film 1-25 (thickness 402 nm). The metallic silver fine particles formed in the nanocomposite film 1-25 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metallic silver fine particles. The metallic silver fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal silver fine particles formed in the film were as follows.
Shape: almost spherical, average particle size: 7.9 nm, maximum particle size: 10.5 nm, minimum particle size: 5.2 nm, volume fraction of silver in nanocomposite film 1-25; 0.9%, interparticle distance Average value of 18.8 nm.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal silver fine particles of the nanocomposite film 1-25, an absorption peak having a peak top of 442 nm and a half width of 76 nm was observed.

[Comparative Example 1-1]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-25 having a thickness of about 1275 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-25 had a gold content per unit area of 20.48 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-25 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-25 (thickness: 765 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-25 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-25:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 11.5 nm, minimum particle size: about 8.0 nm, maximum particle size: about 28.0 nm.
2) Region within the thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-25:
Shape: polyhedral, average particle size: about 23.0 nm, minimum particle size: about 8.0 nm, maximum particle size: about 84.0 nm.
Note that the volume fraction of gold in the nanocomposite film 1-25 was 1.35%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-25, absorption peaks having peak tops of 576 nm and 690 nm and a half-value width of 133 nm were observed.

[Comparative Example 1-2]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-26 having a thickness of about 1260 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-26 had a gold content per unit area of 20.29 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-26 was heat-treated at 400 ° C. for 10 minutes in the air to produce a metal gold fine particle dispersed nanocomposite film 1-26 (thickness: 758 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-26 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-26:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 12.6 nm, minimum particle size: about 8.0 nm, maximum particle size: about 28.0 nm.
2) Region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-26:
Shape: polyhedron, average particle size: about 25.5 nm, minimum particle size: about 8.0 nm, maximum particle size: about 85.0 nm.
The gold volume fraction in the nanocomposite film 1-26 was 1.35%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-26, absorption peaks having peak tops of 580 nm and 682 nm and a half-value width of 147 nm were observed.

[Comparative Example 1-3]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-27 having a thickness of about 1137 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-27 had a gold content per unit area of 17.83 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-27 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-27 (thickness 682 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-27 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region in the thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-27:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 17.0 nm, minimum particle size: about 12.0 nm, maximum particle size: about 27.0 nm.
2) Region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-27:
Shape: polyhedral, average particle size: about 66.8 nm, minimum particle size: about 49.0 nm, maximum particle size: about 83.0 nm.
The gold volume fraction in the nanocomposite film 1-27 was 1.35%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-27, an absorption peak having peak tops of 572 nm and 688 nm and a half width of 189 nm was observed.

[Comparative Example 1-4]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-28 having a thickness of about 1150 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-28 had a gold content per unit area of 18.04 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-28 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-28 (thickness: 690 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-28 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-28:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 20.2 nm, minimum particle size: about 13.0 nm, maximum particle size: about 29.0 nm.
2) Region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-28:
Shape: polyhedral, average particle size: about 65.1 nm, minimum particle size: about 50.0 nm, maximum particle size: about 87.0 nm.
Note that the volume fraction of gold in the nanocomposite film 1-28 was 1.35%.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-28, an absorption peak having peak tops of 620 nm and 698 nm and a half-value width of 216 nm was observed.

[Comparative Example 1-5]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-29 having a thickness of about 1117 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-29 had a gold content per unit area of 17.52 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-29 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-29 (thickness: 670 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-29 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-29:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 23.0 nm, minimum particle size: about 15.0 nm, maximum particle size: about 30.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-29:
Shape: polyhedral, average particle size: about 70.0 nm, minimum particle size: about 52.0 nm, maximum particle size: about 90.0 nm.
The gold volume fraction in the nanocomposite film 1-29 was 1.35%.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-29, an absorption peak having peak tops of 630 nm and 698 nm and a half width of 200 nm was observed.

[Comparative Example 1-6]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-30 having a thickness of about 750 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-30 had a gold content per unit area of 12.05 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-30 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-30 (thickness 450 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-30 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-30:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 7.1 nm, minimum particle size: about 4.0 nm, maximum particle size: about 13.0 nm.
2) Region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-30:
Shape: polyhedral, average particle size: about 17.6 nm, minimum particle size: about 4.0 nm, maximum particle size: about 36.0 nm.
The gold volume fraction in the nanocomposite film 1-30 was 1.35%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-30, absorption peaks having peak tops of 592 nm and 650 nm and a half width of 120 nm were observed.

[Comparative Example 1-7]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-31 having a film thickness of about 640 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-31 had a gold content per unit area of 10.28 μg / cm ² . This gold complex-containing polyimide precursor resin film 1-31 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a purple-colored metal gold fine particle-dispersed nanocomposite film 1-31 (thickness: 384 nm). It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-31 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-31:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 10.0 nm, minimum particle size: about 5.0 nm, maximum particle size: about 16.0 nm.
2) Area within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-31:
Shape: polyhedral, average particle size: about 20.8 nm, minimum particle size: about 5.0 nm, maximum particle size: about 48.0 nm.
The gold volume fraction in the nanocomposite film 1-31 was 1.35%.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-31, absorption peaks having peak tops of 590 nm and 650 nm and a half-value width of 102 nm were observed.

[Comparative Example 1-8]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-32 having a film thickness of about 798 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-32 had a gold content of 12.52 μg / cm ² per unit area. This gold complex-containing polyimide precursor resin film 1-32 was heat-treated in the atmosphere at 200 ° C. for 10 minutes to produce a purple-colored metal gold fine particle-dispersed nanocomposite film 1-32 (thickness: 479 nm). It was confirmed that the metal gold fine particles formed on the nanocomposite film 1-32 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface side of the nanocomposite film 1-32:
Shape: mixed polyhedral and spherical particles, average particle size: about 9.0 nm, minimum particle size: about 7.0 nm, maximum particle size: about 12.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-32:
Shape: polyhedral, average particle size: about 26.0 nm, minimum particle size: about 12.0 nm, maximum particle size: about 39.0 nm.
The gold volume fraction in the nanocomposite film 1-32 was 1.35%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-32, absorption peaks having peak tops of 574 nm and 642 nm and a half width of 102 nm were observed.

[Comparative Example 1-9]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-33 having a film thickness of about 675 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-33 had a gold content per unit area of 10.59 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-33 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 1-33 (thickness: 405 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-33 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-33:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 13.6 nm, minimum particle size: about 10.0 nm, maximum particle size: about 21.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-33:
Shape: polyhedral, average particle size: about 34.6 nm, minimum particle size: about 25.0 nm, maximum particle size: about 50.0 nm.
The gold volume fraction in the nanocomposite film 1-33 was 1.35%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-33, absorption peaks having peak tops of 588 nm and 652 nm and a half-value width of 107 nm were observed.

[Comparative Example 1-10]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 1-34 having a film thickness of about 650 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 1-34 had a gold content per unit area of 10.20 μg / cm ² . The gold complex-containing polyimide precursor resin film 1-34 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 1-34 (thickness 390 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 1-34 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 1-34:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 16.4 nm, minimum particle size: about 14.0 nm, maximum particle size: about 26.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 1-34:
Shape: polyhedral, average particle size: about 41.1 nm, minimum particle size: about 35.0 nm, maximum particle size: about 47.6 nm.
The gold volume fraction in the nanocomposite film 1-34 was 1.35%.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 1-34, absorption peaks having peak tops of 592 nm and 654 nm and a half width of 134 nm were observed.

[Example 2-1]
To 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, 0.522 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added, and the mixture was added at room temperature for 15 minutes under a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 2-1 having a thickness of about 1270 nm on the glass substrate G 1. The gold complex-containing polyimide precursor resin film 2-1 had a content of 20.40 μg / cm ² per unit area of gold. The gold complex-containing polyimide precursor resin film 2-1 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 2-1 (thickness: 762 nm) colored red. The metal gold fine particles formed in the nanocomposite film 2-1 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
1) Area within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 2-1:
Shape: Polyhedral and spherical particles are mixed, average particle diameter: about 10.2 nm, minimum particle diameter: about 4.0 nm, maximum particle diameter: about 38.0 nm.
2) Region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 2-1:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 20.7 nm, minimum particle size: about 4.0 nm, maximum particle size: about 51.0 nm.
The gold volume fraction in the nanocomposite film 2-1 was 1.35%.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 2-1, an absorption peak having a peak top of 570 nm and a half-value width of 115 nm was observed.

[Example 2-2]
To 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, 0.522 g of chloroauric acid tetrahydrate dissolved in 8.00 g of DMAc was added, and the mixture was added at room temperature for 15 minutes under a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 2-2 having a film thickness of about 725 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 2-2 had a gold content per unit area of 11.64 μg / cm ² . The gold complex-containing polyimide precursor resin film 2-2 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 2-2 (thickness: 435 nm) colored red. The metal gold fine particles formed in the nanocomposite film 2-2 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 2-2:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 6.5 nm, minimum particle size: about 3.0 nm, maximum particle size: about 12.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 2-2 (however, when the thickness is less than 600 nm, the upper limit is the film thickness):
Shape: Polyhedral and spherical particles are mixed, average particle size: about 11.6 nm, minimum particle size: about 4.0 nm, maximum particle size: about 25.0 nm.
The gold volume fraction in the nanocomposite film 2-2 was 1.35%.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 2-2, an absorption peak having a peak top of 568 nm and a half-value width of 89 nm was observed.

[Comparative Example 2-1]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 2-3 having a thickness of about 1275 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 2-3 had a gold content per unit area of 20.48 μg / cm ² . The gold complex-containing polyimide precursor resin film 2-3 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 2-3 (thickness: 765 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 2-3 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 2-3:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 11.5 nm, minimum particle size: about 8.0 nm, maximum particle size: about 28.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 2-3:
Shape: polyhedral, average particle size: about 23.0 nm, minimum particle size: about 8.0 nm, maximum particle size: about 84.0 nm.
The gold volume fraction in the nanocomposite film 2-3 was 1.35%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 2-3, an absorption peak having a peak top of 576 nm and 690 nm and a half width of 133 nm was observed.

[Comparative Example 2-2]
0.489 g of chloroauric acid tetrahydrate dissolved in 7.50 g of DMAc was added to 7.50 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 2-4 having a thickness of about 1260 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 2-4 had a gold content of 20.29 μg / cm ² per unit area. The gold complex-containing polyimide precursor resin film 2-4 was heat-treated in the atmosphere at 400 ° C. for 10 minutes to produce a purple-colored metal gold fine particle dispersed nanocomposite film 2-4 (thickness: 758 nm). It was confirmed that the metal gold fine particles formed in the nanocomposite film 2-4 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 2-4:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 12.6 nm, minimum particle size: about 8.0 nm, maximum particle size: about 28.0 nm.
2) Area within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 2-4:
Shape: polyhedron, average particle size: about 25.5 nm, minimum particle size: about 8.0 nm, maximum particle size: about 85.0 nm.
The gold volume fraction in the nanocomposite film 2-4 was 1.35%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 2-4, absorption peaks having peak tops of 580 nm and 682 nm and a half-value width of 147 nm were observed.

[Comparative Example 2-3]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 2-5 having a thickness of about 750 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 2-5 had a gold content per unit area of 12.05 μg / cm ² . This gold complex-containing polyimide precursor resin film 2-5 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 2-5 (thickness 450 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 2-5 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 2-5:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 7.1 nm, minimum particle size: about 4.0 nm, maximum particle size: about 13.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 2-5 (however, when the thickness is less than 600 nm, the upper limit is the film thickness):
Shape: polyhedral, average particle size: about 17.6 nm, minimum particle size: about 4.0 nm, maximum particle size: about 36.0 nm.
The gold volume fraction in the nanocomposite film 2-5 was 1.35%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 2-5, absorption peaks having peak tops of 592 nm and 650 nm and a half width of 120 nm were observed.

[Comparative Example 2-4]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 2-6 having a thickness of about 640 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 2-6 had a gold content of 10.28 μg / cm ² per unit area. This gold complex-containing polyimide precursor resin film 2-6 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 2-6 (thickness 384 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 2-6 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 2-6:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 10.0 nm, minimum particle size: about 5.0 nm, maximum particle size: about 16.0 nm.
2) A region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 2-6 (however, when the thickness is less than 600 nm, the upper limit is the film thickness):
Shape: polyhedral, average particle size: about 20.8 nm, minimum particle size: about 5.0 nm, maximum particle size: about 48.0 nm.
The gold volume fraction in the nanocomposite film 2-6 was 1.35%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 2-6, an absorption peak having a peak top of 590 nm and 650 nm and a half width of 102 nm was observed.

[Example 3-1]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-1 having a film thickness of about 377 nm on the glass substrate G 1. The gold complex-containing polyimide precursor resin film 3-1 had a gold content per unit area of 6.05 μg / cm ² . The gold complex-containing polyimide precursor resin film 3-1 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 3-1 (thickness: 226 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-1 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 8.7 nm, maximum particle size: 20.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 3-1: 1.35 %, Average value of interparticle distance; 20.8 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-1, an absorption peak having a peak top of 550 nm and a half width of 80 nm was observed.

[Example 3-2]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-2 having a film thickness of about 315 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-2 had a gold content per unit area of 5.06 μg / cm ² . This gold complex-containing polyimide precursor resin film 3-2 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 3-2 (thickness 189 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-2 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 10.2 nm, maximum particle size: 21.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 3-2; 1.35 %, Average value of interparticle distance; 24.3 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-2, an absorption peak having a peak top of 564 nm and a half-value width of 76 nm was observed.

[Example 3-3]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-3 having a thickness of about 367 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-3 had a gold content per unit area of 5.89 μg / cm ² . This gold complex-containing polyimide precursor resin film 3-3 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 3-3 (thickness 220 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-3 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 13.8 nm, maximum particle size: 21.0 nm, minimum particle size: 4.0 nm, gold volume fraction in nanocomposite film 3-3: 1.35 %, Average value of interparticle distance; 32.8 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-3, an absorption peak having a peak top of 564 nm and a half-value width of 87 nm was observed.

[Example 3-4]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₃ obtained in Synthesis Example 3, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-4 having a thickness of about 338 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-4 had a gold content per unit area of 5.33 μg / cm ² . The gold complex-containing polyimide precursor resin film 3-4 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 3-4 (thickness: 203 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-4 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 12.4 nm, maximum particle size: 30.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 3-4: 1.35 %, Average value of interparticle distance; 29.6 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 3-4, an absorption peak having a peak top of 556 nm and a half width of 112 nm was observed.

[Example 3-5]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₃ obtained in Synthesis Example 3, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-5 having a film thickness of about 332 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-5 had a gold content per unit area of 5.22 μg / cm ² . The gold complex-containing polyimide precursor resin film 3-5 was heat-treated in the atmosphere at 300 ° C. for 10 minutes to produce a metal gold fine particle dispersed nanocomposite film 3-5 (thickness: 199 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-5 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 14.2 nm, maximum particle size: 30.0 nm, minimum particle size: 6.0 nm, gold volume fraction in nanocomposite film 3-5; 1.35 %, Average value of interparticle distance; 33.8 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 3-5, an absorption peak having a peak top of 564 nm and a half-value width of 111 nm was observed.

[Example 3-6]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₃ obtained in Synthesis Example 3, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-6 having a film thickness of about 413 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-6 had a gold content per unit area of 6.51 μg / cm ² . This gold complex-containing polyimide precursor resin film 3-6 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 3-6 (thickness 248 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-6 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 19.4 nm, maximum particle size; 49.0 nm, minimum particle size: 6.0 nm, gold volume fraction in nanocomposite film 3-6; 1.35 %, Average value of interparticle distance; 46.2 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 3-6, an absorption peak having a peak top of 570 nm and a half width of 94 nm was observed.

[Example 3-7]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-7 having a thickness of about 337 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-7 had a gold content per unit area of 5.28 μg / cm ² . This gold complex-containing polyimide precursor resin film 3-7 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 3-7 (thickness: 202 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-7 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 12.3 nm, maximum particle size: 16.0 nm, minimum particle size: 7.0 nm, gold volume fraction in nanocomposite film 3-7: 1.35 %, Average value of interparticle distance; 29.2 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 3-7, an absorption peak having a peak top of 548 nm and a half width of 78 nm was observed.

[Example 3-8]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-8 having a thickness of about 348 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-8 had a gold content per unit area of 5.46 μg / cm ² . The gold complex-containing polyimide precursor resin film 3-8 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 3-8 (thickness 209 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-8 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 16.5 nm, maximum particle size; 23.0 nm, minimum particle size: 11.0 nm, gold volume fraction in nanocomposite film 3-8; 1.35 %, Average value of interparticle distance; 39.4 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 3-8, an absorption peak having a peak top of 562 nm and a half width of 76 nm was observed.

[Comparative Example 3-1]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-9 having a thickness of about 750 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-9 had a gold content of 12.05 μg / cm ² per unit area. This gold complex-containing polyimide precursor resin film 3-9 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 3-9 (thickness 450 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 3-9 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Area within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 3-9:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 7.1 nm, minimum particle size: about 4.0 nm, maximum particle size: about 13.0 nm.
2) Area within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 3-9:
Shape: polyhedral, average particle size: about 17.6 nm, minimum particle size: about 4.0 nm, maximum particle size: about 36.0 nm.
The gold volume fraction in the nanocomposite film 3-9 was 1.35%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-9, absorption peaks having peak tops of 592 nm and 650 nm and a half width of 120 nm were observed.

[Comparative Example 3-2]
0.348 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-10 having a thickness of about 640 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-10 had a gold content per unit area of 10.28 μg / cm ² . This gold complex-containing polyimide precursor resin film 3-10 was heat-treated in the atmosphere at 400 ° C. for 10 minutes to produce a metal gold fine particle dispersed nanocomposite film 3-10 (thickness 384 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 3-10 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
1) Region within a thickness range of 0 nm to 100 nm from the surface of the nanocomposite film 3-10:
Shape: Polyhedral and spherical particles are mixed, average particle size: about 10.0 nm, minimum particle size: about 5.0 nm, maximum particle size: about 16.0 nm.
2) Region within a thickness range of 100 nm to 600 nm from the surface of the nanocomposite film 3-10:
Shape: polyhedral, average particle size: about 20.8 nm, minimum particle size: about 5.0 nm, maximum particle size: about 48.0 nm.
The gold volume fraction in the nanocomposite film 3-10 was 1.35%.
In addition, as for the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-10, an absorption peak having a peak top of 590 nm and 650 nm and a half width of 102 nm was observed.

[Comparative Example 3-3]
To 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, 1.566 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-11 having a thickness of about 362 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-11 had a gold content per unit area of 16.58 μg / cm ² . This gold complex-containing polyimide precursor resin film 3-11 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a purple-colored metal gold fine particle dispersed nanocomposite film 3-11 (thickness: 217 nm). It was confirmed that the metal gold fine particles formed in the nanocomposite film 3-11 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: Polyhedral and spherical particles are mixed, average particle size: 41.7 nm, maximum particle size: 68.0 nm, minimum particle size: 22.0 nm. The gold volume fraction in the nanocomposite film 3-11 was 3.96%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-11, absorption peaks having peak tops of 570 nm and 640 nm and a half-value width of 171 nm were observed.

[Comparative Example 3-4]
0.522 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-12 having a thickness of about 328 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-12 had a gold content per unit area of 5.15 μg / cm ² . The gold complex-containing polyimide precursor resin film 3-12 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 3-12 (thickness 197 nm) colored red. The metal gold fine particles formed in the nanocomposite film 3-12 were confirmed to be agglomerated in a very small portion. The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: Polyhedral and spherical particles are mixed, average particle size: 23.5 nm, maximum particle size: 34.0 nm, minimum particle size: 16.0 nm. The gold volume fraction in the nanocomposite film 3-12 was 1.35%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 3-12, absorption peaks having peak tops of 574 nm and 620 nm and a half-value width of 92 nm were observed.

[Comparative Example 3-5]
1.566 g of chloroauric acid tetrahydrate dissolved in 52.00 g of DMAc was added to 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 3-13 having a film thickness of about 118 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 3-13 had a gold content per unit area of 5.42 μg / cm ² . The gold complex-containing polyimide precursor resin film 3-13 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 3-13 (thickness 71 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 3-13 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: Polyhedral and spherical particles are mixed, average particle size: 32.0 nm, maximum particle size: 56.0 nm, minimum particle size: 12.0 nm. The gold volume fraction in the nanocomposite film 3-13 was 3.96%.
Further, in the absorption spectrum of localized surface plasmon resonance due to the metal gold fine particles of the nanocomposite film 3-13, absorption peaks having peak tops of 554 nm and 640 nm and a half-value width of 158 nm were observed.

[Example 4-1]
0.726 g of chloroauric acid tetrahydrate dissolved in 7.33 g of DMAc was added to 2.67 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 4-1 having a film thickness of about 298 nm on the glass substrate G 1. The gold complex-containing polyimide precursor resin film 4-1 had a gold content per unit area of 19.15 μg / cm ² . This gold complex-containing polyimide precursor resin film 4-1 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 4-1 (thickness 179 nm) colored red. The metal gold fine particles formed in the nanocomposite film 4-1 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 17.0 nm, maximum particle size; 54.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 4-1, 5.54 %, Average value of interparticle distance; 18.9 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 4-1, an absorption peak having a peak top of 572 nm and a half width of 103 nm was observed.

[Example 4-2]
0.726 g of chloroauric acid tetrahydrate dissolved in 7.33 g of DMAc was added to 2.67 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 4-2 having a thickness of about 337 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 4-2 had a gold content per unit area of 21.61 μg / cm ² . The gold complex-containing polyimide precursor resin film 4-2 was heat-treated at 300 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle-dispersed nanocomposite film 4-2 (thickness: 202 nm) colored red. The metal gold fine particles formed in the nanocomposite film 4-2 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: Mixed polyhedral and spherical particles, average particle size: 22.4 nm, maximum particle size; 68.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 4-2; 5.54 %, Average value of interparticle distance; 24.9 nm.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 4-2, an absorption peak having a peak top of 570 nm and a half width of 103 nm was observed.

[Example 4-3]
0.726 g of chloroauric acid tetrahydrate dissolved in 7.33 g of DMAc was added to 2.67 g of the polyimide precursor resin solution S ₁ obtained in Synthesis Example 1, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Preparation Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 4-3 having a thickness of about 282 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 4-3 had a gold content per unit area of 18.01 μg / cm ² . This gold complex-containing polyimide precursor resin film 4-3 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 4-3 (thickness 169 nm) colored red. The metal gold fine particles formed in the nanocomposite film 4-3 were completely independent of each other, and were dispersed at intervals equal to or larger than the larger particle diameter of the adjacent metal gold fine particles. Metallic gold fine particles were present from the surface layer portion of the matrix resin.
The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: mixed polyhedral and spherical particles, average particle size: 24.5 nm, maximum particle size: 71.0 nm, minimum particle size: 5.0 nm, gold volume fraction in nanocomposite film 4-3; 5.54 %, Average value of interparticle distance; 27.3 nm.
Further, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 4-3, an absorption peak having a peak top of 576 nm and a half-value width of 101 nm was observed.

[Comparative Example 4-1]
0.696 g of chloroauric acid tetrahydrate dissolved in 10.67 g of DMAc was added to 5.33 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, and the mixture was added at room temperature for 15 minutes under a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 4-4 having a film thickness of about 325 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 4-4 had a content of 10.07 μg / cm ² per unit area of gold. This gold complex-containing polyimide precursor resin film 4-4 was heat-treated at 200 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 4-4 (thickness 195 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 4-4 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: Polyhedral and spherical particles are mixed, average particle size: 19.8 nm, maximum particle size: 30.0 nm, minimum particle size: 11.0 nm. The gold volume fraction in the nanocomposite film 4-4 was 2.67%.
Further, in the absorption spectrum of the localized surface plasmon resonance by the metal gold fine particles of the nanocomposite film 4-4, an absorption peak having peak tops of 554 nm and 622 nm and a half width of 109 nm was observed.

[Comparative Example 4-2]
To 8.00 g of the polyimide precursor resin solution S ₂ obtained in Synthesis Example 2, 1.566 g of chloroauric acid tetrahydrate dissolved in 16.00 g of DMAc was added, and the mixture was added for 15 minutes at room temperature in a nitrogen atmosphere. By stirring, a gold complex-containing polyimide precursor resin solution was prepared. The obtained gold complex-containing polyimide precursor resin solution was applied onto the glass substrate G1 of Production Example 1 using a spin coater (manufactured by Mikasa Co., Ltd., SPINCOATER 1H-DX2), then at 70 ° C. for 3 minutes and 130 Drying was performed at a temperature of 10 ° C. for 10 minutes to form a gold complex-containing polyimide precursor resin film 4-5 having a thickness of about 362 nm on the glass substrate G1. The gold complex-containing polyimide precursor resin film 4-5 had a content per gold unit area of 16.58 μg / cm ² . This gold complex-containing polyimide precursor resin film 4-5 was heat-treated at 400 ° C. for 10 minutes in the atmosphere to produce a metal gold fine particle dispersed nanocomposite film 4-5 (thickness: 217 nm) colored purple. It was confirmed that the metal gold fine particles formed in the nanocomposite film 4-5 were partially aggregated. The characteristics of the metal gold fine particles formed in the film were as follows.
Shape: Polyhedral and spherical particles are mixed, average particle size: 41.7 nm, maximum particle size: 68.0 nm, minimum particle size: 22.0 nm. The gold volume fraction in the nanocomposite film 4-5 was 3.96%.
In addition, in the absorption spectrum of localized surface plasmon resonance by the metal gold fine particles in the nanocomposite film 4-5, absorption peaks having peak tops of 570 nm and 640 nm and a half width of 171 nm were observed.

As mentioned above, although embodiment of this invention was described in detail for the purpose of illustration, this invention is not restrict | limited to the said embodiment, A various deformation | transformation is possible. This international application includes Japanese Patent Application No. 2010-178634 filed on August 9, 2010, and Japanese Patent Application Nos. 2010-217173, 2010-2010 filed on Sep. 28, 2010. 217174 and 2010-217175, and claims the priority, the entire contents of which are incorporated herein.

Claims

Metal fine particles in which metal fine particles having an average particle diameter of 3 nm or more are dispersed in the polyimide resin independently from each other at intervals equal to or larger than the particle diameters of the metal fine particles having larger particle diameters in adjacent metal fine particles. A method for producing a metal fine particle composite for producing a composite,
The following steps a and b;
a) A coating solution containing a polyimide precursor resin and a metal compound is applied on a substrate so that the content of the metal is 50 μg / cm 2 or less, dried, and the thickness after drying is Forming a coating film of 1.7 μm or less,
b) The coating film is heat-treated at a temperature in the range of 160 ° C. or more and 450 ° C. or less, thereby reducing the metal ions (or metal salt) in the coating film and precipitating particulate metal that becomes metal fine particles. And a step of dispersing in the coating film and imidizing the polyimide precursor resin in the coating film to form a polyimide resin layer having a thickness of 1 μm or less and an elastic modulus of 10 GPa or less,
A method for producing a metal fine particle composite comprising:
In the metal fine particle composite, the average particle diameter of the metal fine particles is in the range of 3 nm to 25 nm, and the volume fraction is in the range of 0.05% to 1% with respect to the metal fine particle composite. ,
The metal content in the coating solution in the step a is in the range of 0.5 μg / cm 2 to 10 μg / cm 2 , and the thickness of the coating film after drying is 500 nm to 1.7 μm. Within the following range:
2. The method for producing a metal fine particle composite according to claim 1, wherein the thickness of the polyimide resin layer in the step b is in the range of 300 nm to 1 μm.
The metal fine particle composite has an average particle diameter of the metal fine particles in the range of 3 nm to 30 nm and a volume fraction in the range of 0.2% to 5% with respect to the metal fine particle composite. ,
The metal content in the coating solution in the step a is in the range of 10 μg / cm 2 to 50 μg / cm 2 and the thickness of the coating film after drying is 500 nm to 1.7 μm. Is in range,
2. The metal fine particle composite according to claim 1, wherein the thickness of the polyimide resin layer in the step b is in the range of 300 nm to 1 μm and the elastic modulus is in the range of 3 GPa to 10 GPa. Production method.
The metal fine particle composite has an average particle diameter of the metal fine particles in the range of 3 nm to 30 nm and a volume fraction in the range of 0.5% to 5% with respect to the metal fine particle composite. ,
The metal content in the coating solution in the step a is in the range of 5 μg / cm 2 to 10 μg / cm 2 and the thickness of the coating film after drying is in the range of 150 nm to 500 nm. And
2. The metal fine particle composite according to claim 1, wherein the thickness of the polyimide resin layer in the step b is in the range of 100 nm to 300 nm and the elastic modulus is in the range of 5 MPa to 10 GPa. Production method.
The metal fine particle composite has an average particle diameter of the metal fine particles in the range of 5 nm or more and 35 nm or less, and the volume fraction thereof is in the range of 1% or more and 15% or less with respect to the metal fine particle composite,
The metal content in the coating solution in the step a is in the range of 10 μg / cm 2 to 30 μg / cm 2 and the thickness of the coating film after drying is in the range of 150 nm to 500 nm. And
2. The metal fine particle composite according to claim 1, wherein the thickness of the polyimide resin layer in the step b is in the range of 100 nm to 300 nm and the elastic modulus is in the range of 0.5 GPa to 10 GPa. Body manufacturing method.
The method for producing a metal fine particle composite according to any one of claims 1 to 5, wherein the step b is performed in an inert gas atmosphere.
The method for producing a metal fine particle composite according to any one of claims 1 to 6, wherein the metal compound is a precursor of Au.