KR102472173B1 - Chemically stable alkyl aluminum solution, alkyl aluminum hydrolysate composition solution, composition for aluminum oxide film coating formation, article having aluminum oxide film, method for producing same, method for producing aluminum oxide thin-film, method for producing passivation film, passivation film, and solar cell element using same - Google Patents

Abstract

A method for producing an aluminum oxide thin film is disclosed. (1) A solution containing an alkyl aluminum compound or a partial hydrolyzate thereof and a cyclic amide compound of the general formula (4). (2) A method in which a composition containing a partial hydrolyzate of an organoaluminum compound represented by the general formula (6) is applied to the surface of a substrate under an inert gas atmosphere and heated. (3) A method in which an organic aluminum compound represented by the above general formula (6) or an organic solvent solution of a partial hydrolyzate thereof is spray-coated to form a coating film and heated to form an aluminum oxide film. (4) A method of obtaining an aluminum oxide thin film by heating a coating film formed by applying a solution containing an alkyl aluminum compound and an organic solvent having electron donating property and not containing active hydrogen atoms to a substrate. (5) A passivation film forming agent composed of the above solution, and a method for producing a silicon substrate having a passivation film using the same. A silicon substrate and a solar cell device having a passivation film.

Description

Chemically stable alkyl aluminum solution, alkyl aluminum hydrolysis composition solution, composition for forming an aluminum oxide film coating, an article having an aluminum oxide film, a method for producing the same, a method for producing an aluminum oxide thin film, a method for producing a passivation film, a passivation film, and the same Solar cell device using {CHEMICALLY STABLE ALKYL ALUMINUM SOLUTION, ALKYL ALUMINUM HYDROLYSATE COMPOSITION SOLUTION, COMPOSITION FOR ALUMINUM OXIDE FILM COATING FORMATION, ARTICLE HAVING ALUMINUM OXIDE FILM, METHOD FOR PRODUCING SAME, METHOD FOR PRODUCING ALUMINUM OXIDE THIN-FILM, METHOD FOR PRODUCING PASS , PASSIVATION FILM, AND SOLAR CELL ELEMENT USING SAME}

The first aspect of the present invention (hereinafter sometimes referred to as "Invention 1") relates to an alkyl aluminum solution and an alkyl aluminum hydrolyzed composition having high chemical stability to air. The alkyl aluminum solution of the present invention 1 is a stable alkylating agent that is not chemically changed even when handled in air, and a solution and composition that can be used as a reactant. If the solution containing an alkyl aluminum partial hydrolyzate of the present invention 1 is used, an aluminum oxide thin film can be formed even in the air.

The second aspect of the present invention (hereinafter sometimes referred to as "the present invention 2") relates to a composition for coating and forming an aluminum oxide film, a method for producing an article having an aluminum oxide film, and an article having an aluminum oxide film. . The composition for coating and forming an aluminum oxide film of the present invention 2 is a composition capable of forming an aluminum oxide film with excellent adhesion to a substrate.

The third aspect of the present invention (hereinafter sometimes referred to as “the present invention 3”) relates to a composition for coating and forming an aluminum oxide film, a method for producing an article having an aluminum oxide film, and an article having an aluminum oxide film. . The composition for coating and forming an aluminum oxide film of the present invention 3 is a composition capable of forming an aluminum oxide film with excellent adhesion to a substrate.

The fourth aspect of the present invention (hereinafter sometimes referred to as "the present invention 4") relates to a method for producing a simple aluminum oxide thin film. Using the manufacturing method of the present invention 4, an aluminum oxide thin film can be easily formed.

The fifth aspect of the present invention (hereinafter sometimes referred to as “the present invention 5”) relates to a method for producing a passivation film, a passivation film, and a solar cell device using the passivation film. Using the manufacturing method of the present invention 5, a passivation film having a long carrier lifetime can be formed.

CROSS REFERENCES OF RELATED APPLICATIONS

This application is based on Japanese Patent Application No. 2014-168541 filed on August 21, 2014, Japanese Patent Application No. 2014-168549 filed on August 21, 2014, and Japanese Patent Application No. 2014-238778 filed on November 26, 2014. Japanese Patent Application No. 2015-031567, filed on February 20, 2015, and Japanese Patent Application No. 2015-046592, filed on March 10, 2015, the entire disclosures of which are specifically incorporated herein by reference. do.

<First aspect of the present invention>

Because of its high reactivity, alkyl aluminum is a catalyst for polymerization, a raw material for synthesizing higher α-olefins and higher alcohols, a raw material for synthesizing organometallic compounds, a raw material for synthesizing ceramics, a raw material for compound semiconductors, a reactive agent in the field of organic synthesis, etc. It is widely used for various uses (Non-Patent Document 1-1).

Many alkyl aluminums, such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, spontaneously ignite upon contact with air, producing white alumina. Therefore, it cannot be easily handled in the air.

Therefore, an alkyl aluminum solution diluted with an organic solvent such as hexane, heptane, or toluene is often used. However, at concentrations exceeding, for example, 12% by mass in the case of trimethylaluminum diluted with toluene, 12% by mass in the case of triethylaluminum, and 26% by mass in the case of triisobutylaluminium, respectively, each is still natural. Flammability remains. Therefore, in order to handle it safely, it was necessary to use an alkyl aluminum solution diluted to a concentration lower than that (Non-Patent Document 1-2). However, a relatively low-concentration alkyl aluminum solution diluted with an organic solvent has a large bulk volume and is economically unfavorable for transportation or the like.

In addition, even in an alkyl aluminum solution diluted to the point where pyrophoricity is lost, reactivity to air remains, and when it comes into contact with air, it reacts with oxygen in the air to precipitate a white solid, which may block injection needles, piping, etc. have.

On the other hand, a method of forming an aluminum oxide film using an alkyl aluminum solution or an alkyl aluminum hydrolysis composition solution obtained by reacting an alkyl aluminum solution with water is known (Patent Document 1-1).

Patent Document 1-1: WO2012/053433 A1

Non-Patent Document 1-1: "Alkyl Aluminum" Organic Synthetic Chemistry Vol. 43 No. 5 (1985) P475

Non-Patent Document 1-2: "Pyrophoricity of Metal Alkyls", AkzoNobel Technical Bulletin August (2008) P1

However, the alkyl aluminum solution and the aluminum aluminum hydrolysis composition solution described in Patent Literature 1-1 have reactivity with water, so it is necessary to form an aluminum oxide film in an inert gas such as nitrogen or argon. Operation in an inert gas requires an inert gas, inert gas supply facility, inert gas holding facility such as a glove box, and there is a problem that the cost of forming the aluminum oxide thin film is increased.

An object of the present invention 1 is an alkyl aluminum having high air stability, substantially no pyrophoric property, being able to be handled in air, having a relatively small volumetric volume, and being able to be made at a relatively high concentration, which is economically advantageous for movement such as transportation. To provide a solution, moreover to provide a solution containing an alkyl aluminum partial hydrolyzate capable of forming an aluminum oxide thin film in air. In addition to this, the present invention 1 provides a method for producing an aluminum oxide thin film in air.

<Second aspect of the present invention>

Aluminum oxide has excellent properties such as strength, high heat resistance, high thermal conductivity, low coefficient of thermal expansion, insulation, and compactness, and is therefore widely used in various industrial applications.

Aluminum oxide has a shape such as nanoparticles, powder, filler, plate shape, rod shape, and is used for abrasive materials, refractory materials, heat-resistant materials, insulators, and heat dissipation materials. In addition, it is also used as a film having the above-described characteristics, making an alumina sheet for electronic materials, producing an aluminum oxide film, preparing a catalyst carrier, imparting heat resistance, imparting barrier properties to air and moisture, imparting an antireflection effect, imparting an antistatic effect, It is provided for applications such as imparting an antifogging effect, imparting abrasion resistance, etc., and as a binder for ceramic production. Specifically, protective films for mechanical parts and cutting tools, semiconductors, magnetic materials, insulating films such as solar cells, dielectric films, antireflection films, surface devices, magnetic heads, sensor elements such as infrared rays, and packaging materials such as food, medicine, and medical device materials. There is a barrier film for air and moisture, various powders, films, coating films on substrates such as films or molded bodies made of glass or plastic, and applications to heat-resistant materials, high-hardness films, and optical members using these.

As a method for producing aluminum oxide, various methods are known. For example, a so-called Bayer method using bauxite as a starting material and a production method through hydrolysis of aluminum alkoxide are known. In addition, as a general method for producing an aluminum oxide film, for example, a film formation method using a vacuum device, a sputtering method, a chemical vapor deposition (MOCVD) method, and a physical vapor deposition (PVD) method such as vapor deposition are well known.

In the formation of an aluminum oxide film, film formation by a coating method is known. This coating method has advantages such as high productivity and low manufacturing cost because the equipment is simple and the film formation speed is fast, and it is possible to form a large oxide film because there is no need to use a vacuum device and there are no restrictions due to a vacuum container. . As a coating method for forming an aluminum oxide film, a dip coating method (Patent Documents 2-1 and 2-2), a spray pyrolysis method (Patent Document 2-3), a mist CVD method (Non-Patent Document 2-1), and spin coating Methods (Patent Documents 2-4 to 2-6) and the like are known.

The spray pyrolysis method described in Patent Literature 2-3 is a method of obtaining an aluminum oxide film coating by using a solution of an aluminum acetylacetonato complex as a raw material, spraying and drying the solvent at the same time, and then heating the substrate temperature to 500 ° C. or higher. .

The mist CVD method described in Non-Patent Document 2-1 uses a solution of aluminum acetylacetonato complex as a raw material, applies it in the form of a mist, dries the solvent at the same time, and then heats the base material temperature to 300 ° C. or higher to obtain aluminum It is a method of obtaining an oxide film coating.

Various compositions have been proposed as compositions for forming an aluminum oxide film by a coating method. For example, Patent Documents 2-4 to 2-6 describe compositions for forming an aluminum oxide film using a complex of an amine compound and an aluminum hydride compound. Patent Documents 2-5 to 2-7 describe using an organic solvent solution of alkyl aluminum as an organoaluminum compound.

Complexes of these amine compounds and aluminum hydride compounds or solutions of alkyl aluminum in organic solvents are usually used for coating films by spin coating and dip coating. After spin coating or immersion coating, the solvent is dried, and then aluminum oxide can be formed by treating while contacting moisture as an oxygen source.

Moreover, it is also known to use a partial hydrolyzate of an organoaluminium compound as a composition for forming an aluminum oxide film (Patent Documents 2-1, 2-2, 2-5, and 2-6).

A partial hydrolyzate of an organoaluminium compound can also be used for a coating film formed by a spin coating method or a dip coating method. As a general formulation, an aluminum oxide film is obtained by drying the solvent after spin coating or dip coating and then heating the base material to a temperature of 450° C. or higher (Patent Documents 2-1 and 2-2).

Patent Document 2-1: Japanese Unexamined Patent Publication No. 58-95611

Patent Document 2-2: Japanese Unexamined Patent Publication No. 58-91030

Patent Document 2-3: Japanese Laid-Open Patent Publication No. 2007-270335

Patent Document 2-4: Japanese Laid-Open Patent Publication No. 2007-287821

Patent Document 2-5: WO2012/053433A 1

Patent Document 2-6: WO2012/053436A 1

Patent Document 2-7: Japanese Unexamined Patent Publication No. 4-139005

Non-Patent Document 2-1: "Growth and electrical properties of AlOx grown by mist chemical vapor deposition", Toshiyuki Kawaharamura, Takayuki Uchida, Masaru Sanada, Mamoru Furuta, AIP Advances, Vol. 3 (2013) 032135.

In some cases, an aluminum oxide film is coated by a spin coating method or a dip coating method using an organic aluminum compound, particularly, a complex of an amine compound and an aluminum hydride compound or an organic solvent solution of alkyl aluminum. For example, in the case of using the complex of an amine compound and an aluminum hydride compound described in Patent Documents 2-4, in the formation of a thin aluminum oxide film (about 150 nm), treatment in an atmospheric gas atmosphere using an oxygen/nitrogen mixture Forming an aluminum oxide film with On the other hand, according to the examples described in Patent Literatures 2-5 and 2-6, in order to obtain an aluminum oxide film with a thick film thickness (about 200 nm or more), after spin coating or immersion coating and drying the solvent, moisture as an oxygen source and 5 It is necessary to process at 140 degreeC for 3 hours, bringing into contact under pressure at 1 MPa or more. In this method, heat treatment under pressurization for a long time is required, and it is described that metal aluminum is formed in the treatment at 250° C. in an atmospheric gas atmosphere using an oxygen/nitrogen mixture.

In Patent Documents 2-5, even when an organic solvent solution of tridodecyl alkyl aluminum having an alkyl group having 12 carbon atoms is used as the organoaluminum compound, in the treatment under an atmospheric gas atmosphere using a mixture of oxygen / nitrogen, etc., It is described that metallic aluminum is formed.

Thus, when using the composition for forming an aluminum oxide film using a complex of an amine compound and an aluminum hydride compound or an organic solvent solution of alkyl aluminum as the organic aluminum compound, an aluminum oxide film cannot be obtained under atmospheric pressure at 250° C. or less. There is a problem with

However, in recent years, a technology for forming an oxide film on a resin substrate such as a film has been demanded. At that time, 1) lowering the film formation temperature, 2) adhesion to the substrate, and 3) oxide formation state (for example, transparency and homogeneity of the oxide film) are important factors. Therefore, film formation of an aluminum oxide film on a resin substrate is also usually performed by a vapor deposition method using a vacuum or the like.

Particularly, in film formation on a resin having a low surface energy such as polyethylene or polypropylene, 2) adhesion to a substrate is a problem. Undercoat treatment, priming treatment, corona treatment, UV irradiation, chlorination, etc. are performed on the resin surface for the purpose of improving the adhesion of the oxide film to the substrate.

Until now, in a coating film of an aluminum oxide film using a composition for forming an aluminum oxide film coating, a composition having both the performances of 1) to 3) has not been known.

On the other hand, few studies have been conducted on the coating film of an aluminum oxide film using a composition for forming an aluminum oxide film obtained by partially hydrolyzing an organoaluminum compound such as alkyl aluminum. For example, Patent Literature 2-1 discloses coating of an aluminum oxide film at 450°C using an organoaluminum compound having an isopropoxy group as a substituent bonded to Al. However, in this film formation, it is described that cracks enter the thin film unless an additive such as butyl isocyanate having a high molecular weight is added. Further, in Patent Document 2-2, there is a disclosure of a coating film of an aluminum oxide film using an organic aluminum compound having an ethoxy group or an isopropoxy group as a substituent bonded to Al. However, in film formation at 500°C, there were problems such as cracking or the aluminum oxide film not adhering to the substrate.

In this way, in a coating film of an aluminum oxide film in which a coating liquid is directly applied to the surface of a substrate using a coating method such as spin coating or immersion coating, poor adhesion of the aluminum oxide film to the substrate or loss of aluminum oxide during film formation There is a problem that formation of an aluminum oxide film is difficult, such as that a film is not formed (it does not form a film).

Therefore, an object of the present invention 2 is to apply a coating film directly to a substrate surface, in particular, a coating film using a composition containing a partial hydrolyzate of an organic aluminum compound having an alkyl group having 1 to 4 carbon atoms such as triethylaluminum. To solve the problems in coating film formation, in film formation at a relatively low temperature, excellent adhesion to a substrate containing a resin substrate and good oxide formation (for example, transparency and homogeneity of the oxide film) It is to provide a composition for coating and forming an aluminum oxide film, a method for forming an aluminum oxide film using the composition, and a method for manufacturing an article having an aluminum oxide film.

In addition, the present invention 2 is an aluminum oxide film produced using the production method of the present invention 2, in which the oxide formation state (for example, transparency and homogeneity of the oxide film, etc.) is good, and the aluminum oxide film on the substrate has good adhesion It is to provide the goods provided in the state.

<Third aspect of the present invention>

Aluminum oxide has excellent properties such as strength, high heat resistance, high thermal conductivity, low coefficient of thermal expansion, insulation, and compactness, and is therefore widely used in various industrial applications.

The background of aluminum oxide and its preparation method has been described above in Background of the second aspect of the present invention.

In the formation of an aluminum oxide film, film formation by a coating method is known. This coating method has advantages such as high productivity and low manufacturing cost because the equipment is simple and the film formation speed is fast, and it is possible to form a large oxide film because there is no need to use a vacuum device and there are no restrictions due to the vacuum container. . As a coating method for forming an aluminum oxide film, a dip coating method (Patent Documents 3-1 and 3-2), a spray pyrolysis method (Patent Documents 3-3 to 3-7), a mist CVD method (Non-Patent Document 3-1 ), spin coating method (Patent Documents 3-8 to 3-10), etc. are known. Among these, various studies have been made on the formation of an aluminum oxide thin film using a film formation method by spray coating such as spray pyrolysis in particular (Patent Documents 3-3 to 3-7).

In addition, various compositions have been proposed as a composition for forming an aluminum oxide film used in forming an aluminum oxide film by film formation in a coating method. For example, in a method for forming an alumina film of aluminum oxide, it is described that a complex of an amine compound and a hydrogenated aluminum compound is used as a composition for forming an aluminum oxide film (Patent Documents 3-8 to 3-10). It is described that an organic solvent solution of alkyl aluminum is used as an organoaluminum compound (Patent Documents 3-9 to 3-11).

Patent Document 3-1: Japanese Unexamined Patent Publication No. 58-95611

Patent Document 3-2: Japanese Unexamined Patent Publication No. 58-91030

Patent Document 3-3: Japanese Laid-Open Patent Publication No. 2006-161157

Patent Document 3-4: Japanese Laid-Open Patent Publication No. 2007-270335

Patent Document 3-5: Japanese Laid-Open Patent Publication No. 2007-238393

Patent Document 3-6: Japanese Laid-Open Patent Publication No. 2009-120873

Patent Document 3-7: Japanese Laid-Open Patent Publication No. 2010-209363

Patent Document 3-8: Japanese Unexamined Patent Publication No. 2007-287821

Patent Document 3-9: WO2012/053433A 1

Patent Document 3-10: WO2012/053436A 1

Patent Document 3-11: Japanese Unexamined Patent Publication No. 4-139005

Non-Patent Document 3-1: "Growth and electrical properties of AlOx grown by mist chemical vapor deposition" Toshiyuki Kawaharamura, Takayuki Uchida, Masaru Sanada, Mamoru Furuta AIP Advances, Vol.3 (2013)032135.

In recent years, oxide film formation on resin substrates such as films has been demanded, and since 1) lowering the film formation temperature, 2) adhesion to the substrate, and 3) oxide formation state are important factors, aluminum on the resin substrate The film formation of the oxide film is also usually performed by a vapor deposition method using a vacuum or the like.

In studies using the spray coating method known so far, inorganic salts such as aluminum chloride, aluminum acetate, aluminum isopropoxide, aluminum trisacetylacetonate organoaluminum complexes, etc. are used as the aluminum source. . However, the film formation temperature when these are used is high, usually 500 ° C. or higher, and organic aluminum complexes such as aluminum trisacetylacetonate have low solubility in organic solvents, making it difficult to increase the concentration of the aluminum source. In film formation, it is difficult to increase the productivity of the aluminum oxide film. In this way, in the composition for forming an aluminum oxide film composed of an aluminum compound that has been studied so far, it is difficult to form an aluminum oxide film at 250° C. or less that can form a film on a resin substrate.

On the other hand, as a composition for forming an aluminum oxide film that can be used as an aluminum source in a coating film, there is an organic solvent solution of alkyl aluminum as an organic aluminum compound. It is a compound that is not Therefore, it is extremely difficult to carry out spray pyrolysis by spraying alkyl aluminum.

In addition, it is known that the reactivity with oxygen or water increases as the carbon number of alkyl aluminum decreases. Therefore, in Patent Documents 3-9 and 3-10, diisobutylaluminum hydride (alkyl group having 4 carbon atoms) or trioctyl aluminum (alkyl group having 8 carbon atoms) ), alkyl aluminum having 4 or more carbon atoms is used. In addition, although spin coating film formation is used as these film formation methods, film formation by the spray pyrolysis method has not been performed, and it is still unclear.

In addition, hydrides such as diisobutyl aluminum hydride may react with hydride and ether-based solvent in the case of using an ether-based solvent such as anisole, which is used as a solvent, and when the temperature becomes high, There is a risk of decomposition due to chemical reaction.

In this way, in the case where an aluminum oxide film is formed by spraying a composition obtained by dissolving alkyl aluminum in an organic solvent onto a substrate and subjecting it to thermal decomposition, it cannot be said that sufficient studies have been made, and there are still many problems.

In addition, regarding the partial hydrolyzate of alkyl aluminum, as in the case of a composition in which alkyl aluminum is dissolved in an organic solvent, in the case where an aluminum oxide film is formed by spraying onto a substrate and subjecting it to thermal decomposition, examination has not been conducted. I can't say anything, and there are still many challenges.

An object of the present invention 3 is to form an aluminum oxide film by spraying a composition obtained by dissolving alkyl aluminum or a partial hydrolyzate of alkyl aluminum in an organic solvent onto a substrate and thermally decomposing it to obtain an aluminum oxide film having excellent adhesion. It is to provide a method for producing an aluminum oxide film as much as possible and a composition for film formation that can be used for this method.

Furthermore, an object of the present invention 3 is to provide an aluminum oxide film produced using the above manufacturing method, and furthermore to provide an aluminum oxide functional film containing this aluminum oxide film and an article that is a substrate provided with these films and functional films. .

<Fourth aspect of the present invention>

Aluminum oxide has excellent properties in terms of high strength, high heat resistance, high thermal conductivity, low coefficient of thermal expansion, insulation, and the like, and is therefore widely used in various applications.

As the aluminum oxide thin film, preparation of an aluminum oxide sheet for electronic materials, preparation of an aluminum oxide film, preparation of a catalyst carrier, imparting heat resistance, imparting barrier properties to air and moisture, imparting an antireflection effect, imparting an antistatic effect, imparting an antifogging effect, imparting abrasion resistance, etc. It is provided for applications such as application of a binder for ceramic production, and such an aluminum oxide thin film is required to be of high purity (Non-Patent Document 4-1).

Specifically, applications include protective films for cutting tools, insulating films for semiconductors, magnetic materials, solar cells, and the like, surface devices, magnetic heads, infrared sensors, packaging materials for foods, drugs, and medical devices, optical members, and the like.

As a method for producing an aluminum oxide thin film, it is formed by a method such as a sputtering method, a chemical vapor deposition (CVD) method, or an atomic layer deposition (ALD) method.

However, since the sputtering method, the CVD method, the ALD method, and the like require the use of a large airtight container, there are problems such as high manufacturing cost of the aluminum oxide thin film and low material use efficiency.

Compared to the above methods, coating methods such as spin coating, dip coating, screen printing, die coating, and spray coating do not require the use of an airtight container, have simple equipment, fast film forming speed, and low manufacturing cost. There is an advantage that an aluminum oxide thin film can be manufactured.

As a coating method, in particular, various studies have been conducted on the formation of an aluminum oxide thin film using a film formation method by spray coating such as a spray pyrolysis method (Patent Documents 4-1 to 4-2).

Patent Document 4-1: Japanese Laid-Open Patent Publication No. 2007-238393

Patent Document 4-2: Japanese Laid-Open Patent Publication No. 2010-209363

Non-Patent Document 4-1: Yasaka JETI., 10 (2005) P134 to 140

However, in the methods described in Patent Literatures 4-1 to 4-2, when a passivation film is produced by heat treatment (firing) together, it is necessary to degrease (remove) residual organic components such as binder resin and ligand by firing them. , there was a problem that a long time was required for firing or heat treatment at a high temperature of about 400 to 1000°C was required.

In addition, there was a problem that a transparent zinc oxide thin film (transmittance of visible light of 550 nm of 80% or more) was difficult to obtain by heat treatment at a low temperature.

In particular, since firing at 300 ° C. or higher is required, there was a problem that it could not be applied to substrates having no heat resistance, such as plastics.

Trialkyl aluminum compounds, such as triethyl aluminum, are flammable in the air and are compounds that must be stored and used with extreme caution. Therefore, it is practically difficult to use the trialkyl aluminum compound in a spray coating method or the like, which is usually performed in an atmosphere in which water is present, without dilution or the like. A trialkyl compound can reduce risks such as ignitability when diluted in an organic solvent, but there has been no study of spray application of a trialkyl compound diluted in an organic solvent.

In addition, the coating operation in an inert gas requires an inert gas, an inert gas supply facility, and an inert gas holding facility such as a glove box, so that the manufacturing cost of aluminum oxide increases that much, and a new simplification is required. There was a problem.

An object of the present invention 4 is to provide a simple method for producing an aluminum oxide thin film. Using the production method of the present invention 4, it is possible to easily form a transparent aluminum oxide thin film with a small amount of residual organic matter.

<Fifth aspect of the present invention>

In order to increase the efficiency of a crystalline silicon solar cell, it is important to passivate the back surface of the solar cell and suppress recombination of the rear surface of the carrier. Therefore, a passivation film may be formed on the back surface of the silicon substrate.

As this passivation film, a technique using silicon oxide, silicon nitride, aluminum oxide, zinc oxide or the like has been proposed (Patent Document 5-1). Regarding the p-type silicon substrate in particular, silicon nitride, which has a positive fixed charge, is not suitable because leakage current easily occurs, and aluminum oxide, which has a negative fixed charge, is suitable. (Patent Document 5-2).

As a method for producing an aluminum oxide thin film as a passivation film, it is formed by methods such as sputtering, chemical vapor deposition (CVD), and atomic layer deposition (ALD).

However, since the sputtering method, the CVD method, the ALD method, and the like require the use of a large airtight container, there are problems such as high manufacturing cost of the aluminum oxide thin film and low material use efficiency.

Compared to the above methods, coating methods such as spin coating, dip coating, screen printing, die coating, and spray coating do not require the use of an airtight container, the equipment is simple, the film forming speed is fast, and the manufacturing cost is low. There is an advantage that an aluminum oxide thin film can be manufactured.

As the coating method, a production method by spin coating (Non-Patent Document 5-1) and a production method by screen printing (Patent Document 5-3) have been proposed.

Patent Document 5-1: Japanese Laid-Open Patent Publication No. 2009-164544

Patent Document 5-2: Japanese Patent No. 4767110

Patent Document 5-3: Japanese Laid-Open Patent Publication No. 2014-167961

Non-Patent Document 5-1: Thin Solid Films, 517 (2009), 6327-6330

However, in the methods described in Non-Patent Document 5-1 and Patent Document 5-3, when a passivation film is prepared by heat treatment (firing) together, residual organic components such as binder resin and ligand are degreased (removed) by firing. Since it is necessary, there was a problem that a long time was required for firing or that heat treatment at a high temperature of 650 to 1000 ° C was required.

In addition, the carrier life time of the passivation film manufactured by the method described in Non-Patent Document 5-1 and Patent Document 5-3 is 100 to 500 μs when the substrate wafer thickness is about 700 μm, compared to the passivation film manufactured by the ALD method. It was short, and improvement of the new carrier life time was requested|required.

An object of the present invention 5 is to provide a simple passivation film manufacturing method, a passivation film, and a solar cell device using the same. If the manufacturing method of the present invention 5 is used, a passivation film having a long carrier life time can be formed.

As for the said Patent Documents 1-1 to 5-3 and Non-Patent Documents 1-1 to 5-1, their entire description is specifically incorporated herein as an indication.

Invention 1 is as follows.

[1-1] An alkyl aluminum compound-containing solution containing an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (provided that the alkyl group has 1 to 6 carbon atoms and may be the same or different) and a solvent ,

The solvent is an organic compound having a boiling point of 160° C. or higher, an amide structure represented by the following general formula (4), and a cyclic structure (hereinafter referred to as “cyclic amide compound”),

The solution containing the cyclic amide compound in an amount greater than 2.6 in molar ratio relative to the alkyl aluminum compound:

.

.

[1-2] The cyclic amide compound is N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetra The solution described in [1-1], which is hydro-2(1H)-pyrimidinone or a mixture thereof.

[1-3] The solution according to any one of [1-1] or [1-2], wherein the content of the alkyl aluminum compound is 15% by mass or more.

[1-4] Any one of [1-1] to [1-3], wherein the dialkyl aluminum and/or trialkyl aluminum is an alkyl aluminum compound represented by the following general formula (1) or (2) Solutions described:

(In the formula, R ¹ represents a methyl group or an ethyl group, and R ² represents a halogen, a methyl group or an ethyl group.)

(In the formula, R ³ represents an isobutyl group, and R ⁴ represents a halogen or isobutyl group.)

[1-5] The solution described in [1-4], wherein the alkyl aluminum compound represented by the general formula (1) is triethylaluminum or trimethylaluminum.

[1-6] The solution described in [1-4], wherein the alkyl aluminum compound represented by the general formula (2) is triisobutylaluminum.

[1-7] The solution described in [1-6], containing 30% by mass or more of the alkyl aluminum compound represented by the general formula (2).

[1-8] The solution according to any one of [1-1] to [1-7], further containing a solvent other than the cyclic amide compound.

[1-9] Alkyl aluminum containing a partial hydrolyzate of dialkyl aluminum, trialkyl aluminum or an alkyl aluminum compound composed of a mixture thereof (provided that the alkyl group has 1 to 6 carbon atoms and may be the same or different) and a solvent As a solution containing a partial hydrolyzate,

The solvent is an organic compound having a boiling point of 160° C. or higher, an amide structure represented by the following general formula (4), and a cyclic structure (hereinafter referred to as “cyclic amide compound”),

The partial hydrolyzate is hydrolyzed with water in a molar ratio in the range of 0.5 to 1.3 with respect to aluminum in the alkyl aluminum compound, the above solution:

.

.

[1-10] The solution described in [1-9], which contains at least one of the cyclic amide compounds in a molar ratio with respect to aluminum in the alkyl aluminum compound.

[1-11] The cyclic amide compound is N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetra The solution described in [1-9] or [1-10], which is hydro-2(1H)-pyrimidinone or a mixture thereof.

[1-12] In any one of [1-9] to [1-11], wherein the dialkyl aluminum and/or trialkyl aluminum is an alkyl aluminum compound represented by the following general formula (1) or (2) Solutions described:

(In the formula, R ¹ represents a methyl group or an ethyl group, and R ² represents hydrogen, a halogen, a methyl group or an ethyl group.)

(In the formula, R ³ represents an isobutyl group, and R ⁴ represents hydrogen, a halogen, or an isobutyl group.)

[1-13] The solution according to any one of [1-9] to [1-11], wherein the trialkyl aluminum is an alkyl aluminum compound represented by the following general formula (3):

(In the formula, R ⁵ represents a methyl group, an ethyl group or an isobutyl group.)

[1-14] The solution according to any one of [1-9] to [1-13], further comprising a solvent other than the cyclic amide compound.

[1-15] A method for producing an aluminum oxide thin film, comprising applying the solution containing an alkyl aluminum partial hydrolyzate according to any one of [1-9] to [1-14] to a substrate to obtain an aluminum oxide thin film.

The present invention 2 is as follows.

[2-1] (A) A step of partially hydrolyzing an organoaluminum compound represented by the following general formula (6) in an organic solvent to obtain a composition containing a partial hydrolyzate of the organoaluminum compound, provided that the above Partial hydrolysis is performed using water having a molar ratio to the organoaluminum compound in the range of 0.4 to 1.3; a step of obtaining the composition;

(B) a step of applying the partial hydrolyzate-containing composition to at least a part of the surface of a substrate in an inert gas atmosphere to form a coating film;

(C) Method for producing an article provided with an aluminum oxide film, including a step of forming an aluminum oxide film by heating the base material on which the coating film is formed at a temperature of 400 ° C. or less under an inert gas atmosphere:

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

[2-2] The manufacturing method described in [2-1], wherein the inert gas atmosphere used in the steps (B) and (C) does not contain substantially no water.

[2-3] The production method described in [2-1] or [2-2], wherein the application of the partial hydrolyzate-containing composition in the step (B) is performed at a temperature in the range of 20 to 350°C.

[2-4] The manufacturing method according to any one of [2-1] to [2-3], wherein the heating temperature in the step (C) is in the range of 40 to 400°C.

[2-5] The coated base material obtained in the step (B) is heated to a temperature of 20 to 200° C. under an inert gas atmosphere, at least part of the organic solvent in the coating film is removed, and then subjected to the step (C) to aluminum The production method according to any one of [2-1] to [2-4], wherein an oxide film is formed.

[2-6] In the step (A), after mixing the organoaluminum compound and water, the mixture is heated to a temperature of 30 to 80 ° C. to obtain a composition containing a partial hydrolyzate [2-1] to the production method according to any one of [2-5].

[2-7] The partial hydrolyzate-containing composition prepared in the step (A) is filtered to remove insoluble matter, and then used in the step (B) according to any one of [2-1] to [2-6]. manufacturing method.

[2-8] Spray coating method, dip coating method, spin coating method, slit coating method, slot coating method, bar coating method, roll coating method, curtain coating method, electrostatic coating method, ink jet method, screen printing method The manufacturing method according to any one of [2-1] to [2-7], wherein the composition is applied to a substrate.

[2-9] The production method according to any one of [2-1] to [2-8], wherein the organic solvent used for preparing the partial hydrolyzate is an organic solvent containing a hydrocarbon compound and/or an electron-donating solvent. .

[2-10] The concentration of the partial hydrolyzate in the composition containing the partial hydrolyzate prepared in the step (A) is in the range of 0.1 to 30% by mass, as described in any one of [2-1] to [2-9]. manufacturing method.

[2-11] The organoaluminum compound represented by the general formula (6) used in the step (A) is any one of [2-1] to [2-10], wherein R ¹ in the formula is a methyl group or an ethyl group. The manufacturing method according to claim 1.

[2-12] [2-1] to [2-1], wherein the organoaluminum compound represented by the general formula (6) used in the step (A) is triethylaluminum or a mixture of organoaluminum compounds containing triethylaluminum. 2-11] the manufacturing method described in any one of them.

[2-13] The manufacturing method according to any one of [2-1] to [2-12], wherein the substrate used in the step (B) is a glass substrate or a resin substrate.

[2-14] A composition containing a partial hydrolyzate of the organoaluminum compound obtained by partially hydrolyzing an organoaluminum compound represented by the following general formula (6) in an organic solvent,

(A) the partial hydrolysis is performed using water having a molar ratio to the organoaluminum compound in the range of 0.4 to 1.3, and

(b) the composition is a material for use in forming an aluminum oxide film in which film coating is performed under an inert gas atmosphere;

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

[2-15] The film coating formation performed in the inert gas atmosphere is (b1) a step of applying the partial hydrolyzate-containing composition to at least a part of the surface of a substrate in an inert gas atmosphere to form a coating film, and

(b2) The composition according to [2-14], including a step of forming an aluminum oxide film by heating the substrate on which the coating film is formed at a temperature of 400° C. or lower under an inert gas atmosphere.

[2-16] The composition according to [2-14] or [2-15], which is filtered using a filter having a pore diameter of 3 µm or less and is substantially free of insoluble matter.

[2-17] The composition according to any one of [2-14] to [2-16] for forming a transparent aluminum oxide film adhered to a substrate.

[2-18] Using the method according to any one of [2-1] to [2-13] or the composition according to any one of [2-14] to [2-17], in an inert gas atmosphere An article having a manufactured aluminum oxide film.

[2-19] The article is provided with the aluminum oxide film described in [2-18], which is a composite in which an aluminum oxide film is adhered to a substrate or a composite film in which an aluminum oxide film and a composite film having layers other than the aluminum oxide film are adhered to a substrate. article.

This invention 3 is as follows.

[3-1] (A) A step of forming a coating film by spraying an organic aluminum compound represented by the following general formula (6) or an organic solvent solution of a partial hydrolyzate thereof on at least a part of the surface of a substrate (provided that the above The partial hydrolyzate is a material obtained by partially hydrolyzing the organoaluminum compound in an organic solvent using water at a molar ratio of 0.7 or less to the organoaluminum compound, and the spray coating is 0.5 mol% to 30 mol% carried out under an inert gas atmosphere containing the moisture of);

(B) heating the base material on which the coating film is formed at a temperature of 400 ° C. or lower in an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture, and forming an aluminum oxide film from the coating film. Method for producing an article having an aluminum oxide film:

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

[3-2] In the step (A), an organic solvent solution of an organoaluminum compound is used,

In general formula (6), R ¹ represents a straight-chain or branched alkyl group having 1 to 3 carbon atoms, R ² and R ³ are independently a straight-chain or branched alkyl group having 1 to 3 carbon atoms, a straight-chain or branched alkyl group having 1 to 7 carbon atoms, The production method described in [3-1], which represents a branched alkoxyl group, acyloxy group or acetylacetonate group.

[3-3] the organic solvent contains an organic solvent having electron donating property, and

The production method described in [3-2], wherein the concentration of the organoaluminum compound in the solution is 0.1 to 35% by weight.

[3-4] The production method according to [3-3], wherein the number of moles of molecules constituting the electron-donating organic solvent is equal to or greater than the number of moles of the organic aluminum compound.

[3-5] The production method according to any one of [3-2] to [3-4], wherein the temperature of the surface of the substrate is 20 to 300°C in the spray coating in step (A).

[3-6] In the step (A), an organic solvent solution of a partial hydrolyzate of an organoaluminum compound is used,

The production method described in [3-1], wherein the organic solvent used in the step (A) is an organic solvent containing a hydrocarbon compound and/or an organic solvent having electron donating property.

[3-7] The production method described in [3-6], wherein the concentration of the partial hydrolyzate in the organic solvent solution is in the range of 0.1 to 35% by mass.

[3-8] The step (A) is performed under heating at a temperature of 400 ° C. or lower, and heating is performed in the step (B) simultaneously with or continuously with the step (A), [3-6] or [3 -7].

[3-9] The manufacturing method according to any one of [3-1] to [3-8], wherein the spray coating is performed by a spray coating method, a spray pyrolysis method, an electrostatic coating method, or an inkjet method.

[3-10] The production method according to any one of [3-1] to [3-9], wherein R ¹ in the general formula (6) is a methyl group or an ethyl group.

[3-11] A film-forming composition comprising an organic solvent solution of an organoaluminum compound represented by the following general formula (6),

The composition is a material for use in the formation of an aluminum oxide film in which coating and formation of the film is performed under an inert gas atmosphere containing 0.5 mol% to 30 mol% of water:

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 3 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 3 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

[3-12] A film-forming composition containing a partial hydrolyzate of the organoaluminum compound obtained by partially hydrolyzing an organoaluminum compound represented by the following general formula (6) in an organic solvent,

(A) the partial hydrolysis is performed using water having a molar ratio to the organoaluminum compound of 0.7 or less, and

(b) the composition is a material for use in the formation of an aluminum oxide film in which film coating is carried out under an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture;

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

[3-13] The film coating formation performed in an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture,

(c1) forming a coating film by spraying the composition on at least a part of the surface of a substrate under an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture; and

(c2) heating the base material on which the coated film is formed at a temperature of 400 ° C. or less under an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture to form an aluminum oxide film [3-11 ] or the composition described in [3-12].

[3-14] The composition according to any one of [3-11] to [3-13] for forming a transparent aluminum oxide film adhered to a substrate.

[3-15] Using the method according to any one of [3-1] to [3-10] or the composition according to any one of [3-11] to [3-14], 0.5 mol% to An article having an aluminum oxide film produced under an inert gas atmosphere containing 30 mol% of moisture.

[3-16] The article is provided with the aluminum oxide film described in [3-15], which is a composite in which an aluminum oxide film is adhered to a substrate or a composite film having an aluminum oxide film and a composite film having layers other than the aluminum oxide film adhered to a substrate. article.

Invention 4 is as follows.

[4-1] an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (however, the alkyl group of dialkyl aluminum and trialkyl aluminum has 1 to 6 carbon atoms and may be the same or different), and an electron hole Forming a coating film by applying a solution containing an alkyl aluminum compound containing an organic solvent having a female and not containing an active hydrogen atom to a substrate in air as droplets having an average particle diameter of 1 to 100 µm, and the formed coating film A method for producing an aluminum oxide thin film characterized by heating an organic solvent after drying or in parallel with drying the organic solvent to obtain aluminum oxide.

[4-2] The production method described in [4-1], wherein the droplets have an average particle diameter in the range of 3 to 30 µm.

[4-3] The production method according to [4-1] or [4-2], wherein the application to the substrate is performed on a substrate heated to a temperature of 300°C or less.

[4-4] The manufacturing method according to any one of [4-1] to [4-3], wherein the atmospheric temperature in the air is 50°C or lower and the relative humidity in terms of 25°C is 20 to 90%.

[4-5] The manufacturing method according to any one of [4-1] to [4-4], wherein the coating is performed by spray coating, mist CVD, or an inkjet method.

[4-6] Any one of [4-1] to [4-5], wherein the dialkyl aluminum and/or trialkyl aluminum is an alkyl aluminum compound represented by the following general formula (8) or (9) Manufacturing method described:

(In the formula, R ¹ represents a methyl group or an ethyl group.)

(In the formula, R ² represents an isobutyl group, and R ³ represents hydrogen or an isobutyl group.)

[4-7] The production method described in [4-6], wherein the alkyl aluminum compound represented by the general formula (8) is triethylaluminium.

[4-8] The production method described in [4-7], wherein the triethylaluminum content in the alkyl aluminum compound-containing solution is 1% by mass or more and 10% by mass or less.

[4-9] The manufacturing method according to any one of [4-1] to [4-8], wherein the aluminum oxide thin film has a vertical transmittance of 80% or more at 550 nm of visible light.

Invention 5 is as follows.

[5-1] an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (however, the alkyl group of dialkyl aluminum and trialkyl aluminum has 1 to 6 carbon atoms and may be the same or different), and, A passivation film forming agent composed of a solution containing an alkyl aluminum compound containing an organic solvent having electron donating property and not containing an active hydrogen atom.

[5-2] The passivation film forming agent described in [5-1], wherein the dialkyl aluminum and/or trialkyl aluminum is an alkyl aluminum compound represented by the following general formula (8) or (9):

(In the formula, R ¹ represents a methyl group or an ethyl group.)

(In the formula, R ² represents an isobutyl group, and R ³ represents hydrogen or an isobutyl group.)

[5-3] The passivation film forming agent described in [5-2], wherein the alkyl aluminum compound represented by the general formula (8) is triethyl aluminum.

[5-4] The passivation film-forming agent described in [5-3], wherein the content of the triethyl aluminum in the alkyl aluminum compound-containing solution is 1% by mass or more and 10% by mass or less.

[5-5] Forming a coating film by applying the passivation film-forming agent described in [5-1] to [5-4] as droplets having an average particle diameter of 1 to 100 μm on at least a part of the back surface of a silicone substrate, and heating the formed coating film to aluminum oxide after drying an organic solvent or in parallel with drying the organic solvent to form a passivation film.

[5-6] The production method according to [5-5], wherein the droplets have an average particle diameter in the range of 3 to 30 µm.

[5-7] The production method described in [5-5] or [5-6], wherein the coating is performed by a spray coating method.

[5-8] The preparation described in [5-7], wherein the substrate temperature during spray application is in the range of 300 to 550°C, and/or the temperature during heating after spray application is in the range of 300 to 550°C. Way.

[5-9] A silicon substrate with a passivation film, characterized in that it is produced by the method according to any one of [5-5] to [5-8].

[5-10] A solar cell device using a silicon substrate having the passivation film described in [5-9].

According to the present invention 1, it is possible to provide a high-concentration alkyl aluminum solution that is not pyrophoric, is stable in air, is easy to handle, and has a small bulk volume, which is economically advantageous for movement such as transportation. Further, according to the present invention 1, it is possible to provide a solution containing an alkyl aluminum partial hydrolyzate that is stable in air, and therefore easy to handle, and capable of forming an aluminum oxide thin film in air.

According to the present invention 2, in film formation at a relatively low temperature, an aluminum oxide film having excellent adhesion to a substrate including a resin substrate and having a good oxide formation state (for example, transparency and homogeneity of the oxide film) is applied A composition for coating and forming an aluminum oxide film that can be provided by film formation can be provided. By using this composition, the coating liquid, which is the composition of the present invention 2, is directly applied to the surface of the substrate and heated at a relatively low temperature. Even in a coating film, adhesion to a substrate including a resin substrate is excellent, and the state of oxide formation ( For example, an aluminum oxide film having good transparency and homogeneity of the oxide film) can be directly formed on the surface of the substrate. In addition, according to the present invention 2, a method of forming an aluminum oxide film using the composition of the present invention 2 and a method of manufacturing an article made of a substrate having an aluminum oxide film on the surface can be provided.

Using the production method and the composition for producing an aluminum oxide film according to the present invention 3, an aluminum oxide film having excellent adhesion to a substrate and good oxide formation can be formed even at a low film formation temperature simply by coating and heating. .

More specifically, according to the present invention 3, an organoaluminum compound having an alkyl group having 1 to 3 carbon atoms as a substituent, such as triethylaluminum (2 carbon atoms) or a partial hydrolyzate thereof, is mixed with an electron-donating organic solvent or the like. By using a coating solution dissolved in a solvent, it is easy to handle a reactive compound such as alkyl aluminum in the film formation operation, and it is easy to control the reaction in the spray film formation. , it is possible to form an aluminum oxide film having excellent adhesion to a substrate and a good oxide formation state only by coating and heating.

In addition, the aluminum oxide film produced by the method of the present invention 3 has excellent adhesion to the substrate and a good oxide formation state, so that an alumina sheet for electronic materials, an aluminum oxide film are prepared, a catalyst carrier is prepared, heat resistance is imparted, air, It is provided for applications such as imparting barrier properties to moisture, imparting antireflection effect, imparting antistatic effect, imparting antifogging effect, imparting wear resistance, etc., and binders for ceramic manufacturing, specifically, protective films for mechanical parts and cutting tools, semiconductors , magnetic materials, insulating films such as solar cells, dielectric films, antireflection films, surface devices, magnetic heads, sensor elements such as infrared rays, barrier films for air and moisture in packaging materials such as food, medicine, and medical device materials, various powders As an aluminum oxide functional film such as an aluminum oxide film used for applications such as films, films made of glass or plastics, coating films on substrates such as molded bodies, and heat-resistant materials or high-hardness films using these, optical members, and binders for ceramic manufacturing, can be applied

Substrates provided with these aluminum oxide films and aluminum oxide functional films include heat-resistant materials such as heat-resistant films, insulating materials, materials such as barrier films for moisture and oxygen, anti-reflection materials such as anti-reflection films and glass, and high-hardness films. or can be used as a material.

According to the present invention 4, an aluminum oxide thin film can be simply produced at a low temperature, and a transparent aluminum oxide thin film with a small amount of residual organic matter can be easily formed.

According to the present invention 5, an aluminum oxide thin film with a small residual organic matter can be easily manufactured at a low temperature, and a passivation film with a long carrier life time can be formed.

Figure 1a is a ¹ H-NMR spectrum of a triethylaluminum hydrolysis composition NMP solution.
Figure 1b is an IR spectrum of a dried triethylaluminum hydrolysis composition NMP solution by transmission method.
Figure 1c is a photograph of the appearance of an aluminum oxide thin film.
Figure 1d is an IR spectrum by the ATR method of the aluminum oxide thin film.
1E is an IR spectrum of a glass substrate (EagleXG, manufactured by Corning) by the ATR method.
2A is a view showing a spray film forming apparatus;
Figure 2b is a ¹ H-NMR spectrum after vacuum drying of the composition A obtained in Example 2-1
2C is an ATR-IR spectrum of an aluminum oxide film obtained on a glass substrate by film formation by heating at 130° C. in Example 2-1.
2D is an ATR-IR spectrum of a glass substrate used in film formation by heating at 130° C. in Example 2-1.
Figure 2e is a ¹ H-NMR spectrum after vacuum drying of the composition B obtained in Example 2-3
Figure 2f is a ¹ H-NMR spectrum after vacuum drying of the composition C obtained in Examples 2-5
2g is a ¹ H-NMR spectrum after vacuum drying of composition K obtained in Examples 2-15
Figure 2h is a ²⁷ Al-NMR spectrum after vacuum drying of the composition K obtained in Examples 2-15
2i is a ¹ H-NMR spectrum after vacuum drying of composition N obtained in Examples 2-20
Figure 2j is a ¹ H-NMR spectrum after vacuum drying of the composition O obtained in Example 2-21
Figure 2k is a ²⁷ Al-NMR spectrum after vacuum drying of the composition O obtained in Example 2-21
2l is an ATR-IR spectrum of an aluminum oxide film obtained on a porous polypropylene (PP) film by film formation by heating at 50 ° C. in a nitrogen atmosphere in Examples 2-23
2m is an ATR-IR spectrum of an aluminum oxide film obtained on a porous polypropylene (PP) film by film formation by heating at 50 ° C. in an air atmosphere in Examples 2-23
2n is an ATR-IR spectrum of a porous polypropylene (PP) film used in film formation by heating at 50 ° C. in an air or nitrogen atmosphere in Examples 2-23
Figure 2o is a scanning electron microscope photograph (thin film cross-section) of an aluminum oxide film obtained on a glass substrate by film formation by heating at 50 ° C. in a nitrogen atmosphere in Example 2-24
2p is a scanning electron micrograph (thin film surface) of an aluminum oxide film obtained on a glass substrate by film formation by heating at 50° C. under a nitrogen atmosphere in Example 2-24.
2q is an ATR-IR spectrum (before peel test) of an aluminum oxide film obtained on a polypropylene (PP) film by film formation by heating at 100 ° C. in a nitrogen atmosphere using composition H in Examples 2-38
2r is an ATR-IR spectrum after a peel test of an aluminum oxide film obtained on a polypropylene (PP) film by film formation by heating at 100 ° C. in a nitrogen atmosphere using composition H in Examples 2-38
Figure 2s is an ATR-IR spectrum (before peel test) of an aluminum oxide film obtained on a polypropylene (PP) film by film formation by heating at 100 ° C. in a nitrogen atmosphere using composition 3 in Comparative Examples 2-6
2t is an ATR-IR spectrum after a peel test of an aluminum oxide film obtained on a polypropylene (PP) film by film formation by heating at 100 ° C. in a nitrogen atmosphere using composition 3 in Comparative Examples 2-6
2U is a scanning electron microscope photograph (thin film surface) of an aluminum oxide film formed on paper obtained in Example 2-40.
3A is a view showing a spray film forming apparatus;
3B is a scanning electron micrograph (thin film surface) of an aluminum oxide film obtained in Example 3-1-1.
3C is a scanning electron micrograph (thin film cross-section) of an aluminum oxide film obtained in Example 3-1-1.
3D is a scanning electron micrograph (thin film surface) of an aluminum oxide film obtained in Example 3-1-10.
3E is a scanning electron micrograph (thin film surface) of an aluminum oxide film obtained in Example 3-1-17.
Figure 3f is a ¹ H-NMR spectrum after vacuum drying of the composition F obtained in Example 3-2-4
3g is a scanning electron micrograph (thin film surface) of an aluminum oxide film obtained on a glass substrate by film formation by heating at 200° C. in a nitrogen atmosphere in Example 3-2-1
3H is a scanning electron microscope photograph (thin film cross-section) of an aluminum oxide film obtained on a glass substrate by film formation by heating at 200° C. under a nitrogen atmosphere in Example 3-2-1.
3I is a scanning electron micrograph (thin film surface) of an aluminum oxide film obtained on a glass substrate by film formation by heating at 200° C. under a nitrogen atmosphere in Example 3-2-2.
3j is a scanning electron microscope photograph (thin film cross-section) of an aluminum oxide film obtained on a glass substrate by film formation by heating at 200° C. under a nitrogen atmosphere in Example 3-2-2.
Figure 4a is an IR spectrum by the base alkali-free glass ATR method.
Figure 4b is an IR spectrum by the ATR method of the aluminum oxide thin film.
Figure 4c is an IR spectrum by the ATR method of the aluminum oxide thin film.
Figure 4d is an IR spectrum by the ATR method of the aluminum oxide thin film.
5A is a diagram showing a spray film forming device;
5B is a diagram showing an example of an embodiment of the solar cell element of the present invention 5;

<First aspect of the present invention>

[Alkyl Aluminum Containing Solution]

The first aspect of the first aspect of the present invention contains an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum or a mixture thereof (provided that the alkyl group has 1 to 6 carbon atoms and may be the same or different) and a solvent. It is an alkyl aluminum containing solution. The solvent is an organic compound (cyclic amide compound) having a boiling point of 160°C or higher, an amide structure represented by the following general formula (4), and a cyclic structure:

.

.

The alkyl aluminum compound-containing solution of the present invention can chemically stabilize dialkyl aluminum, trialkyl aluminum or a mixture thereof by containing the cyclic amide compound as a solvent. The reason why the cyclic amide compound is preferable as the solvent is not clear, but it is difficult to volatilize at a high boiling point. It is estimated that stability against air is greatly improved by the increase in stiffness by Usually, a compound having an amide structure reacts with an alkyl aluminum compound. Therefore, it was presumed that the alkyl aluminum compound undergoes a chemical change by mixing with the cyclic amide compound in a prior prediction. However, it was found that the alkyl aluminum compound and the cyclic amide compound did not react unexpectedly and maintained the state of the alkyl aluminum compound.

The ratio of the alkyl aluminum compound and the cyclic amide compound in the solution of the present invention preferably contains one or more cyclic amide compounds in a molar ratio with respect to the alkyl aluminum compound from the viewpoint of keeping the alkyl aluminum compound chemically stable. do. By containing the cyclic amide compound in an amount exceeding 2.6 in molar ratio with respect to the alkyl aluminum compound, chemical changes such as spontaneous combustion of the solution can be suppressed.

Cyclic amide compounds are, for example, N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetrahydro- 2(1H)-pyrimidinone, or mixtures thereof, with N-methyl-2-pyrrolidone being particularly preferred, since it is inexpensively available.

The dialkyl aluminum and/or trialkyl aluminum may be, for example, an alkyl aluminum compound represented by the following general formula (1) or (2):

(In the formula, R ¹ represents a methyl group or an ethyl group, and R ² represents a halogen, a methyl group or an ethyl group.)

(In the formula, R ³ represents an isobutyl group, and R ⁴ represents a halogen or isobutyl group.)

As an example of the compound represented by General formula (1), trimethyl aluminum, dimethyl aluminum chloride, triethyl aluminum, diethyl aluminum chloride etc. are mentioned, for example. The alkyl aluminum compound represented by the general formula (1) may be, in particular, triethylaluminum or trimethylaluminum.

As an example of the compound represented by General formula (2), triisobutyl aluminum, diisobutyl aluminum chloride, etc. are mentioned, for example. The alkyl aluminum compound represented by the general formula (2) may be triisobutylaluminum in particular.

The content of the alkyl aluminum compound in the alkyl aluminum-containing solution of the present invention is not particularly limited, but the higher the content of the alkyl aluminum compound in the alkyl aluminum-containing solution, the higher the transport efficiency. From the viewpoint of the transport efficiency, for example, It may be 15 mass % or more. However, as long as it is a mixture with a predetermined amount of cyclic amide compound and maintains a chemically stable state, it is not intended to be limited to 15% by mass or more.

The concentration of the alkyl aluminum compound, when R ¹ in Formula (1) is an ethyl group, is preferably 15% by mass or more from the viewpoint of providing a high-concentration solution, and considering stability to air, it is preferably 21% by mass or less do. When R ¹ is a methyl group, it is preferably 15% by mass or more from the viewpoint of providing a high-concentration solution, and preferably 21% by mass or less in consideration of stability to air.

It is preferable to contain 30 mass % or more of the concentration of the alkyl aluminum compound represented by General formula (2) from a viewpoint of transport efficiency (provision of a high-concentration solution). On the other hand, considering the stability to air, it is preferably 40% by mass or less.

The alkyl aluminum-containing solution of the present invention may further contain a solvent other than the cyclic amide compound. By adding a solvent other than the cyclic amide compound, polarity, viscosity, boiling point, economy, etc. can be adjusted. Examples of solvents other than cyclic amide compounds include aliphatic hydrocarbons such as n-hexane, octane, and n-decane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane, and ethylcyclohexane; Aromatic hydrocarbons, such as benzene, toluene, xylene, and cumene; hydrocarbon solvents such as mineral spirits, solvent naphtha, kerosene, and petroleum ether; Ethers such as diethyl ether, tetrahydrofuran, diisopropyl ether, dioxane, din-butyl ether, dialkyl ethylene glycol, dialkyl diethylene glycol, dialkyl triethylene glycol, glyme, diglyme, A triglyme solvent etc. are mentioned. The addition amount of the solvent other than the cyclic amide compound is not limited as long as it does not interfere with the effect of the cyclic amide compound, and can be, for example, 100 parts by mass or less with respect to 100 parts by mass of the cyclic amide compound. However, the range that can be added varies depending on the type of the alkyl aluminum compound, the cyclic amide compound, and the type of solvent other than the cyclic amide compound.

The mixing of the cyclic amide compound and, if necessary, a solvent other than the cyclic amide compound and the alkyl aluminum compound can be performed in a reaction vessel under an inert gas atmosphere, and each can be introduced according to any conventional method. The alkyl aluminum compound can be introduced into the reaction vessel even as a mixture with an organic solvent other than the cyclic amide compound.

The order of introduction into the mixing vessel is the order of the alkyl aluminum compound, the cyclic amide compound, and, if necessary, a solvent other than the cyclic amide compound, or the cyclic amide compound, and, if necessary, the solvent other than the cyclic amide compound, and the alkyl aluminum. Any of introduction in order or all at the same time may be sufficient.

The introduction time into the mixing vessel can be appropriately set depending on the type and capacity of the raw materials to be mixed, but can be, for example, between 1 minute and 10 hours. As the temperature at the time of introduction, an arbitrary temperature between -15 and 150°C can be selected. However, in consideration of safety such as exclusion of the risk of ignition at the time of introduction, it is preferably in the range of -15 to 80 ° C.

At the time of introducing the raw material into the mixing vessel, the stirring step after the introduction may be either a batch operation type, a semi-batch operation type, or a continuous operation type.

The alkyl aluminum-containing solution of the present invention is useful as a material that can be used even in air in the following applications, for example.

Alkylating agents such as methylation and ethylation in organic synthesis;

·Special polymer catalysts, quasi-catalysts,

Reducing agent using diisobutylaluminum hydride in organic synthesis

[Alkyl aluminum partial hydrolyzate containing solution]

The second aspect of the first aspect of the present invention is a partial hydrolyzate of an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (provided that the alkyl group has 1 to 6 carbon atoms and may be the same or different). and a solvent containing an alkyl aluminum partial hydrolyzate. The said solvent is an organic compound (cyclic amide compound) which has a boiling point of 160 degreeC or more, has an amide structure represented by the following general formula (4), and has a cyclic structure. In addition, the said partial hydrolyzate is hydrolyzed with water in the range of 0.5-1.3 at the molar ratio with respect to aluminum in the said alkyl aluminum compound.

The cyclic amide compound is the same as the compound described in the first aspect of the first aspect of the present invention, and is N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3- dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone, or mixtures thereof.

The dialkyl aluminum and/or trialkyl aluminum may be an alkyl aluminum compound represented by the general formula (1) or (2). The alkyl aluminum compound represented by the general formula (1) or (2) is also the same as the compound described in the first aspect of the first aspect of the present invention.

The trialkyl aluminum is preferably an alkyl aluminum compound represented by the following general formula (3):

(In the formula, R ⁵ represents a methyl group, an ethyl group or an isobutyl group.)

As an example of the compound represented by General formula (3), trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, etc. are mentioned. Triethylaluminum is preferable from the viewpoint of low cost per unit mass of aluminum.

The molar ratio of the cyclic amide compound to aluminum in the alkyl aluminum compound is preferably 1 or more from the viewpoint of obtaining a chemically stable partial hydrolyzate-containing solution. In addition, by using the alkyl aluminum compound as a partial hydrolyzate, the chemical stability to air is improved, but the stability is still lacking, so that a mixture with a predetermined amount of a cyclic amide compound is obtained from the viewpoint of obtaining a chemically stable partial hydrolyzate-containing solution. It is preferable to

The partial hydrolyzate-containing solution of the present invention may further contain a solvent other than the cyclic amide compound. The types and addition amounts of solvents other than the cyclic amide compound are the same as those described in the first aspect of the first aspect of the present invention.

Partial hydrolysis of the alkyl aluminum compound is performed using water or a solution containing water within a range of 0.5 to 1.3 in a molar ratio to the alkyl aluminum compound. When the molar ratio of water to the alkyl aluminum compound is less than 0.5, it becomes liquid even after drying the solvent, making it difficult to easily form a uniform aluminum oxide film. From the viewpoint of forming a uniform aluminum oxide film, the molar ratio of water to the alkyl aluminum compound is more preferably 0.8 or more. On the other hand, when the molar ratio of water to the alkyl aluminum compound exceeds 1.3, solvent-insoluble gels and solids precipitate, making it difficult to form a uniform aluminum oxide film by the gels and solids. It is also possible to remove the precipitated gel or solid by filtration, but this is undesirable because it leads to loss of aluminum content.

The partial hydrolysis reaction is carried out by adding water or a solution containing water to a solution in which the alkyl aluminum compound is dissolved in the cyclic amide compound and, if necessary, a solvent other than the cyclic amide compound, under an inert gas atmosphere. do Although water itself may be added, it is preferable to carry out by adding a solution containing water from the point of control of heat generation at the time of reaction between the alkyl aluminum compound and water.

The concentration of the alkyl aluminum compound in the alkyl aluminum compound solution to which water or a solution containing water is added can be 0.1 to 50% by mass, and is preferably in the range of 0.1 to 30% by mass.

The addition of water or a solution containing water to the alkyl aluminum compound solution can be appropriately set depending on the type and capacity of the raw materials to be mixed, but can be set within the range of 1 minute to 10 hours, for example. As the temperature at the time of addition, an arbitrary temperature between -15 and 150°C can be selected. However, considering safety and the like, it is preferably in the range of -15 to 80°C.

After adding water or a solution containing water, the aging reaction may be carried out for 0.1 to 50 hours in order to further advance the partial hydrolysis reaction of the alkyl aluminum compound and water. As the aging reaction temperature, an arbitrary temperature may be selected between -15 and 150°C. However, considering the shortening of the aging reaction time, etc., it is preferably in the range of 25 to 150 ° C.

The cyclic amide compound and, if necessary, a solvent other than the cyclic amide compound, an alkyl aluminum compound, water, or a solution containing water can be introduced into the reaction vessel in accordance with any conventional method. The pressure of the reaction vessel is not limited. The hydrolysis reaction step may be any of a batch operation type, a semi-batch operation type, and a continuous operation type, and is not particularly limited, but a batch operation type is preferable.

By the partial hydrolysis reaction, a solution containing the alkyl aluminum partial hydrolyzate is obtained. When the alkyl aluminum compound is trimethylaluminum, triethylaluminum, or triisobutylaluminum, analysis of the partially hydrolyzed composition has been conducted for a long time, but the composition of the product is different depending on the report, and the composition of the product has not been clearly specified. not. In addition, the composition of the product also changes depending on the solvent, concentration, addition molar ratio of water, addition temperature, reaction temperature, reaction time, and the like.

It is presumed that the alkyl aluminum partial hydrolyzate in the method of the present invention is a mixture of compounds containing structural units represented by the following general formula (5):

(In the formula, R ⁵ is the same as R ⁵ in the general formula (3), and m is an integer of 1 to 80.)

When a trace amount of solid or the like is precipitated after the completion of the partial hydrolysis reaction, the solid or the like can be removed by purification by a method such as filtration or chromatography.

The solid content concentration of the above alkyl aluminum partial hydrolyzate-containing solution can be adjusted by concentration (solvent removal). Moreover, the solid content concentration, polarity, viscosity, boiling point, economical efficiency, etc. can be adjusted suitably by adding the solvent used for reaction, and the solvent different from the one used for reaction.

Examples of the solvent different from that used in the reaction include aliphatic hydrocarbons such as n-hexane, octane, and n-decane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane, and ethylcyclohexane; Aromatic hydrocarbons, such as benzene, toluene, xylene, and cumene; hydrocarbon solvents such as mineral spirits, solvent naphtha, kerosene, and petroleum ether; Ethers such as diethyl ether, tetrahydrofuran, diisopropyl ether, dioxane, din-butyl ether, dialkyl ethylene glycol, dialkyl diethylene glycol, dialkyl triethylene glycol, glyme, diglyme, A triglyme solvent etc. are mentioned.

The content of the alkyl aluminum partial hydrolyzate in the alkyl aluminum partial hydrolyzate-containing solution of the present invention can be appropriately determined depending on the application. The content can be adjusted by adjusting the amount of the cyclic amide compound and/or the amount of solvents other than the cyclic amide compound. The content of the alkyl aluminum partial hydrolyzate can be appropriately adjusted in the range of 0.1 to 50% by mass, for example. However, it is not intended to be limited to this range.

[Method for producing aluminum oxide thin film]

The method for producing an aluminum oxide thin film of the present invention is a method of obtaining an aluminum oxide thin film by applying the solution containing an alkyl aluminum partial hydrolyzate of the present invention to a substrate.

Application to the substrate is a spin coating method, dip coating method, screen printing method, bar coating method, slit coating method, die coating method, gravure coating method, roll coating method, curtain coating method, spray pyrolysis method, electrostatic spray pyrolysis method It can be carried out by a conventional method such as a method, an inkjet method, or a mist CVD method.

Although the application to the base material can be carried out either under an inert atmosphere or an air atmosphere, it is preferable to carry out the application under an air atmosphere from the point of view of economical efficiency because the apparatus is simpler.

Although the application to the base material can be carried out either under pressure or under reduced pressure, it is preferable to carry out the application under atmospheric pressure from the point of view of economy because the equipment is also simple.

The said base material is glass, such as lead glass, soda glass, borosilicate glass, and non-alkali glass; oxides such as silica (SilicA), alumina, titania, zirconia, and complex oxides; Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethyl methacrylate (PMMA), polycarbonate (PC), polyphenylene sulfide (PPS), polystyrene ( PS), polyvinyl alcohol (PVA), polyvinyl chloride (PVC), polyvinylidene chloride, cyclic polyolefin (COP), ethylene-vinyl acetate copolymer (EVA), polyimide, polyamide, polyethersulfone (PES ), polyurethane, triacetate, triacetylcellulose (TAC), cellophane, polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polyfluorinated polymers such as vinyl (PVF), perfluoroalkoxyfluorine resin (PFA), tetrafluorinated ethylene/hexafluorinated propylene copolymer (ETFE), and ethylene/chlorotrifluoroethylene copolymer (ECTFE); and the like. have.

The shape of the base material may include a powder, film, plate, or a three-dimensional structure having a three-dimensional shape.

After applying the solution containing the alkyl aluminum partial hydrolyzate, the base material is brought to a predetermined temperature, and the solvent is dried or simultaneously baked at a predetermined temperature to form an aluminum oxide thin film. In addition, when the coating is performed by the spray pyrolysis method, the electrostatic spray pyrolysis method, the inkjet method, or the mist CVD method, the substrate can be heated to a predetermined temperature before application, so that the solvent is dried simultaneously with the application or fired simultaneously with the drying. it is possible

A predetermined temperature for drying the solvent may be selected from an arbitrary temperature, for example, from 20 to 250°C. The solvent may be dried over, for example, 0.5 to 60 minutes. However, it is not intended to be limited to these ranges.

The predetermined temperature for sintering to form the aluminum oxide can be selected arbitrarily, for example, from 50 to 550°C. However, considering the type of substrate, it is appropriate to set the temperature at which the substrate is not damaged. When the predetermined temperature for firing is the same as the predetermined temperature for drying the solvent, drying and firing of the solvent can be performed simultaneously. It is possible to bake the solvent-dried precursor film over, for example, 0.5 to 300 minutes.

The film thickness of the aluminum oxide thin film obtained as described above may be, for example, 0.005 to 3 µm. If necessary, the film thickness of the aluminum oxide thin film can be increased by repeating the above coating, drying, and baking steps a plurality of times.

If necessary, the aluminum oxide thin film obtained as described above is heated under an oxidizing gas atmosphere such as oxygen, under a reducing gas atmosphere such as hydrogen, under a water vapor atmosphere containing a large amount of moisture, or under a plasma atmosphere such as argon, nitrogen, or oxygen. , the crystallinity and compactness of aluminum oxide can also be improved by heating to a predetermined temperature. Residual organic substances in the aluminum oxide thin film obtained by light irradiation such as ultraviolet rays or microwave treatment can be removed.

<Second aspect of the present invention>

The manufacturing method of the article provided with the aluminum oxide film of this invention includes the process of the following (A), (B), and (C).

(A) a step of partially hydrolyzing an organoaluminum compound represented by the following general formula (6) in an organic solvent to obtain a composition containing a partial hydrolyzate of the organoaluminum compound (however, the partial hydrolysis is carried out using water in a range of 0.4 to 1.3 in the molar ratio to the organoaluminum compound),

(B) a step of applying the partial hydrolyzate-containing composition to at least a part of the surface of a substrate in an inert gas atmosphere to form a coating film;

(C) Step of forming an aluminum oxide film by heating the substrate on which the coating film is formed at a temperature of 400° C. or less under an inert gas atmosphere:

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

Process (A)

In step (A), the organic aluminum compound represented by the general formula (6) is partially hydrolyzed in an organic solvent to obtain a composition containing a partial hydrolyzate of the organoaluminum compound.

Specific examples of the straight-chain or branched alkyl group having 1 to 4 carbon atoms represented as R ¹ in the organoaluminum compound represented by the general formula (6) include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, iso A butyl group, sec-butyl group, and tert-butyl group are mentioned. In the compound represented by the general formula (6), it is preferable that R ¹ is a compound having 1, 2, 3 or 4 carbon atoms. In the compound represented by the general formula (6), it is particularly preferable that R ¹ is an ethyl group having 2 carbon atoms. The straight-chain or branched alkyl group having 1 to 4 carbon atoms represented by R ² and R ³ is also the same as the above R ¹ .

Specific examples of the straight-chain or branched alkoxyl group having 1 to 7 carbon atoms represented by R ² and R ³ in the organoaluminum compound represented by the general formula (6) include a methoxy group, an ethoxy group, an isopropoxy group, n- butoxy group, sec-butoxy group, t-butoxy group, phenoxy group, methoxyethoxy group and the like. As a specific example of an acyloxy group, an acetoxy group, a propionyloxy group, a butyryloxy group, an isobutyryloxy group, etc. are mentioned.

The compound represented by the general formula (6) is preferably trimethylaluminum, triethylaluminum, diethylaluminum ethoxide, triisobutylaluminum, or trin-butylaluminum, in terms of low price and easy availability. In particular, trimethylaluminum, triethylaluminum, diethylaluminum ethoxide, and triisobutylaluminum are preferable because they are inexpensive and have a large amount of use as a polymerization cocatalyst and are easy to obtain. Triethylaluminum, which is the most numerous and inexpensive, is preferred.

These compounds are generally available as commercial items, and it is known that an alkyl group having a different number of carbon atoms from R ¹ , R ² and R ³ and hydrogen are contained in trace amounts or small amounts in organoaluminum compounds. For example, in triethyl aluminum suitable for the present invention, in addition to the ethyl group, which is the majority of the alkyl groups in R ¹ , R ² and R ³ , an n-butyl group, hydrogen, etc. are included, but in the present invention, these can be used without problems. can be used

The partial hydrolysis is performed using water having a molar ratio to the organoaluminum compound in the range of 0.4 to 1.3. When the molar ratio of water to organoaluminum compound is less than 0.4, good quality (transparent and It is difficult to form an aluminum oxide film having good adhesion to the substrate). When the molar ratio of water to the organoaluminum compound exceeds 1.3, a gel-like substance insoluble in the organic solvent precipitates, which hinders the formation of a homogeneous aluminum oxide film.

The molar ratio of water to organoaluminum compound is preferably in the range of 0.4 to 1.25. The composition for coating and forming an aluminum oxide film obtained by hydrolyzing an organoaluminum compound within the range of the added amount of water forms an aluminum oxide film of good quality (transparent and having good adhesion to a substrate) by coating and heating under an inert gas atmosphere. can form Here, the inert gas atmosphere is an atmosphere made of an inert gas that does not substantially contain moisture or an oxygen source such as oxygen, and indicates an atmosphere in which, for example, each of moisture and oxygen is 1000 ppm or less, preferably 400 ppm or less. The moisture content in the inert gas atmosphere can be controlled by the dew point temperature, and if it is 400 ppm or less, it can be controlled within the range of, for example, 5 ppm (dew point temperature -66°C) to 375 ppm (dew point temperature -30°C). In addition, considering the ease of operation, it may be controlled to be in the range of 100 ppm (dew point temperature -42 ° C) to 375 ppm (dew point temperature -30 ° C). The type of inert gas is not particularly limited, but examples thereof include helium, argon, and nitrogen. Among these, nitrogen is particularly preferable in terms of cost.

The organic solvent used for preparing the partial hydrolyzate may be one having solubility in the organoaluminum compound represented by the general formula (6), and examples thereof include electron-donating organic solvents and hydrocarbon compounds. In addition, as the organic solvent, those having water solubility may be used, or organic solvents having water solubility and those having low water solubility may be used in combination. The organic solvent may be an electron-donating organic solvent, a hydrocarbon compound, or a mixture thereof.

Examples of the electron-donating organic solvent include 1,2-diethoxyethane, 1,2-dibutoxyethane, diethyl ether, din-propyl ether, diisopropyl ether, dibutyl ether, and cyclophenylmethyl. Ether solvents such as ether, tetrahydrofuran, dioxane, glyme, diglyme, triglyme, anisole, and methoxytoluene, amine solvents such as trimethylamine, triethylamine, and triphenylamine can be heard As an organic solvent having electron donating property, 1,2-diethoxyethane, tetrahydrofuran, and dioxane are preferable.

As the above-mentioned hydrocarbon compounds, straight-chain or branched hydrocarbon compounds or cyclic hydrocarbon compounds having 5 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, aromatic hydrocarbon compounds having 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, and these A mixture of can be exemplified.

As specific examples of these hydrocarbon compounds, pentane, n-hexane, heptane, isohexane, methylpentane, octane, 2,2,4-trimethylpentane (isooctane), n-nonane, n-decane, n-hexadecane aliphatic hydrocarbons such as octadecane, eicosan, methylheptane, 2,2-dimethylhexane, and 2-methyloctane; Alicyclic hydrocarbons such as cyclopentane, cyclohexanemethylcyclohexane, and ethyl cyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, cumene, and trimethylbenzene, mineral spirits, hydrocarbons such as solvent naphtha, kerosene, and petroleum ether A solvent can be mentioned.

In the composition containing a partial hydrolyzate obtained in step (A), R ¹ , R ² , and R ³ remaining in the composition after partial hydrolysis with water contain hydrogen or a straight-chain or branched alkyl group having 1 to 4 carbon atoms. If not, alcohol such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, and diethylene glycol can be used as a solvent that can coexist in the composition.

The partial hydrolysis is carried out by adding water to a solution in which the compound represented by formula (6) is dissolved in the organic solvent, or by mixing an organic solvent solution of the compound represented by formula (6) with water. . The concentration of the compound represented by the general formula (6) in the solution is appropriately determined in consideration of the solubility in the organic solvent and the concentration of the partial hydrolyzate in the obtained partial hydrolyzate composition, etc., but is, for example, 0.1 to 50% by mass. It is suitable to set it as the range of, and the range of 0.1-35 mass % is preferable.

Addition or mixing of water may be performed without mixing water with other solvents or after mixing water with other solvents. The addition or mixing of water can be performed over a period of time from 60 seconds to 10 hours, depending on the scale of the reaction. It is preferable to add by dropping water to the organic aluminum compound of General formula (6) which is a raw material from a viewpoint that the yield of a partial hydrolyzate is favorable. Addition of water can be performed, for example, without stirring the solution of the compound represented by Formula (6) and the electron-donating organic solvent (in a state left still) or while stirring. As the temperature during addition, an arbitrary temperature between -90 and 150°C can be selected. It is -15 to 30 degreeC is preferable from a viewpoint of the reactivity of water and an organoaluminium compound.

After the addition of water, in order to further advance the hydrolysis reaction between water and the compound represented by the general formula (6), for example, from 1 minute to 48 hours, leave without stirring (in a state of standing) or stir. can Regarding the reaction temperature, the reaction can be carried out at an arbitrary temperature between -90 and 150°C. It is -15 to 80 degreeC is preferable from a viewpoint of obtaining a partial hydrolyzate in high yield. The pressure in the hydrolysis reaction is not limited. Usually, it can be carried out at normal pressure (atmospheric pressure). The progress of the hydrolysis reaction between water and the compound represented by the general formula (6) can be monitored, if necessary, by sampling the reaction mixture, analyzing the sample by NMR or IR, or sampling the generated gas. .

The organic solvent, the organic aluminum compound of the general formula (6) as a raw material, and water may be introduced into the reaction vessel according to any conventional method, and the organic aluminum compound and water may be introduced as a mixture with the organic solvent, respectively. have. The hydrolysis reaction step may be any of a batch operation type, a semi-batch operation type, and a continuous operation type, and is not particularly limited, but a batch operation type is preferable.

By the above hydrolysis reaction, the organic aluminum compound of the general formula (6) is partially hydrolyzed by water, and a product containing a partial hydrolyzate is obtained. In the case where the organoaluminum compound of the general formula (6) is trimethylaluminum, triethylaluminum or the like, analysis of the hydrolyzate has been performed for a long time. However, the results differ depending on the report, and the composition of the product is not clearly specified. Also, the composition of the product may be changed by the molar ratio of addition of water or the reaction time. The main component of the product in the method of the present invention is a partial hydrolyzate, and the partial hydrolyzate is presumed to be a mixture of compounds containing structural units represented by the following general formula (7):

(In the formula, Q is the same as any one of R ¹ , R ² , and R ³ in the general formula (6), and m is an integer from 1 to 200.)

After completion of the hydrolysis reaction, some or all of the product may be recovered and/or purified by general methods such as filtration, concentration, extraction, column chromatography, and the like. Under conditions where the molar ratio of water to the organoaluminum compound of the general formula (6) is relatively high, insoluble matter may be generated. It is desirable to obtain a composition containing a partial hydrolyzate that is substantially free of water.

The partial hydrolyzate (solid content) separated and recovered from the organic solvent by the above method can be dissolved in an organic solvent for film coating formation different from the organic solvent used for the reaction to form a coating composition. However, the composition containing a partial hydrolyzate, which is a reaction product mixture, may be used as a composition for application without being separated from the organic solvent as it is or after appropriately adjusting the concentration.

Examples of the organic solvent usable as the organic solvent for film coating formation include straight-chain and branched hydrocarbon compounds or cyclic hydrocarbon compounds having 5 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, and 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. Aromatic hydrocarbon compounds having 6 to 12 carbon atoms and mixtures thereof can be exemplified.

As specific examples of these hydrocarbon compounds, pentane, n-hexane, heptane, isohexane, methylpentane, octane, 2,2,4-trimethylpentane (isooctane), n-nonane, n-decane, n-hexadecane aliphatic hydrocarbons such as octadecane, eicosan, methylheptane, 2,2-dimethylhexane, and 2-methyloctane; Alicyclic hydrocarbons such as cyclopentane, cyclohexanemethylcyclohexane, and ethyl cyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, cumene, and trimethylbenzene, mineral spirits, hydrocarbons such as solvent naphtha, kerosene, and petroleum ether solvent can be increased.

Other examples of the organic solvent usable as the organic solvent for film coating formation include 1,2-diethoxyethane, 1,2-dibutoxyethane, diethyl ether, din-propyl ether, and diiso. Ether solvents such as propyl ether, dibutyl ether, cyclopentyl methyl ether, tetrahydrofuran, dioxane, glyme, diglyme, triglyme, anisole, methoxytoluene, trimethylamine, triethylamine , Amine solvents, such as triphenylamine, etc. are mentioned.

In addition, these organic solvents are not only used individually, but also can be used in mixture of two or more types.

Further, in the composition for forming an aluminum oxide film coating, when R ¹ , R ² , R ³ remaining in the composition after hydrolysis is an alkoxide group, methanol, ethanol, n- Alcohols such as propyl alcohol, isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, and diethylene glycol can also be used as the organic solvent for film coating formation.

The solid content concentration of the partial hydrolyzate of the composition containing the partial hydrolyzate obtained in step (A) may be, for example, in the range of 0.1 to 30% by mass. Although the higher the concentration, the film can be produced with fewer coatings. However, considering the solubility of the reaction product containing the partial hydrolyzate of the organoaluminum compound, for example, the ease of formation of an aluminum oxide film, it is preferably 0.1 to 25 % by mass, more preferably 0.1 to 15% by mass.

The composition containing the partial hydrolyzate obtained in the step (A) corresponds to the composition for forming an aluminum oxide film coating of the present invention. The composition for coating and forming an aluminum oxide film of the present invention can form an aluminum oxide film of good quality (transparent and having good adhesion to the substrate) on a substrate by performing film coating in an inert gas atmosphere. This manufacturing method includes steps (B) and (C). Steps (B) and (C) are described below.

Process (B)

The composition containing the partial hydrolyzate obtained in step (A) is applied to at least a part of the surface of the substrate under an inert gas atmosphere to form a coated film.

The coating method on the surface of the substrate is not particularly limited, and examples include spray coating method, dip coating method, spin coating method, slit coating method, slot coating method, bar coating method, roll coating method, curtain coating method, and spraying. Conventional methods such as thermal decomposition, electrostatic coating, inkjet, and screen printing can be used.

The spray pyrolysis method or the electrostatic coating method is a method in which coating and film formation can be performed simultaneously while heating a substrate. Therefore, the solvent can be dried simultaneously with application, and depending on conditions, heating for drying the solvent may not be necessary. Depending on the conditions, in addition to drying, at least part of the reaction of the partial hydrolyzate to aluminum oxide may also proceed. Therefore, there are cases where aluminum oxide film formation by heating in the step (C), which is a subsequent step, can be performed more easily. The heating temperature of the substrate at the time of application and film formation in the spray pyrolysis method may be, for example, in the range of 20 to 400°C, preferably 50 to 400°C. In particular, when a substrate having low heat resistance such as resin is used for the substrate, it can be performed in the range of 20 to 350°C, and in the case of a substrate having even lower heat resistance, 20 to 250°C.

The application of the composition to the surface of the substrate is performed under an inert gas atmosphere such as nitrogen. In the present invention, the application of the composition containing a partial hydrolyzate is carried out under an inert gas atmosphere to: 1) lower the film formation temperature, 2) adhere to the substrate, 3) form the oxide (for example, the transparency of the oxide film) homogeneity, etc.), it becomes possible to form an aluminum oxide film. The inert gas atmosphere is an atmosphere made of an inert gas that does not substantially contain moisture or an oxygen source such as oxygen, and represents an atmosphere in which, for example, moisture and oxygen are respectively 1000 ppm or less, preferably 400 ppm or less. The moisture content in the inert gas atmosphere can be controlled by the dew point temperature, and if it is 400 ppm or less, it can be controlled within the range of, for example, 5 ppm (dew point temperature -66°C) to 375 ppm (dew point temperature -30°C). In addition, considering the ease of operation, it may be controlled to be in the range of 100 ppm (dew point temperature -42 ° C) to 375 ppm (dew point temperature -30 ° C).

On the other hand, when there is no water or oxygen completely, in the structure of the partial hydrolyzate represented by the general formula (7), the Al-Q site may become unreacted and remain in the film, so the homogeneity of the obtained film, etc. The coexistence of moisture and oxygen is permitted within a range in which desired physical properties are not impaired. Specifically, each of moisture and oxygen in an inert gas atmosphere can be 1000 ppm or less, preferably 400 ppm or less.

During this coating or subsequent drying of the solvent, especially in a situation where the solvent remains, when the moisture or oxygen in the inert gas atmosphere is greater than the above-mentioned value, the reaction between the partial hydrolyzate and the moisture and oxygen proceeds excessively, This is not preferable because deposits are powdered before film formation, transparency of the film is impaired, and the homogeneity and adhesion of the obtained aluminum oxide film are deteriorated.

Although there is no limitation in particular about an inert gas, For example, helium, argon, nitrogen, etc. are mentioned. Among these, nitrogen is particularly preferable in terms of cost. Regarding the pressure at the time of application, any of atmospheric pressure, pressurized pressure, and reduced pressure can be applied, but it is usually preferable to carry out the application at atmospheric pressure because it is convenient on the device and does not cost money.

2A shows a spray film forming device as an example of a film forming device by spray coating that can be used in the present invention. In the drawing, (1) denotes a spray bottle filled with a coating liquid, (2) a substrate holder, (3) a spray nozzle, (4) a compressor, and (5) a substrate. In spray application, a substrate is placed in a substrate holder 2, heated to a predetermined temperature using a heater as necessary, and then compressed from a spray nozzle 3 arranged above the substrate in an inert gas atmosphere. An inert gas and a coating liquid are simultaneously supplied, the coating liquid is atomized and sprayed, and the partial hydrolyzate-containing composition of the present invention is coated on a substrate (step (B)).

In the spray application of the coating liquid, it is preferable to discharge the coating liquid from a spray nozzle so that the size of the droplet is within the range of 30 μm or less, taking into consideration the adhesion to the substrate, the ease of evaporation of the solvent, and the like. In addition, considering that the solvent evaporates to some extent until reaching the substrate from the spray nozzle and the size of the droplet decreases, etc., the distance between the spray nozzle and the substrate is 50 cm or less to form a coating film of the composition containing a partially hydrolyzate. It is preferable from the viewpoint of being able to form.

In addition, without heating the substrate and the ambient temperature, the compressed inert gas and the coating liquid are simultaneously supplied from the spray nozzle 3 disposed above the substrate, and the coating liquid is atomized and sprayed onto the substrate. A coating film of a composition containing a partial hydrolyzate can be formed. In addition, although either application|coating in the method of this invention can be carried out under pressure or reduced pressure, it is preferable that it is carried out by atmospheric pressure because it is convenient also on an apparatus, and there is no cost.

The base material for forming the aluminum oxide film in the above production method is not limited in material, shape, size, and the like. Examples of the material include inorganic materials such as glass, metal and ceramics, resin substrates such as plastics, organic materials such as paper and wood, and composites thereof.

These substrates are not particularly limited as long as they do not interfere with the formation of an aluminum oxide film. Examples of the glass include glass such as quartz glass, borosilicate glass, soda glass, alkali-free glass and lead glass, and oxides such as sapphire. Moreover, as a metal, stainless steel, such as SUS304 and SUS316, aluminum, iron, copper, titanium, silicon, nickel, gold, silver, alloy containing these, etc. are mentioned. Examples of the ceramics include oxides such as alumina, silica, zirconia and titania, nitrides such as nitrogen boride, aluminum nitride, silicon nitride, titanium nitride and gallium nitride, carbon compounds such as silicon carbide, and composites containing these. Further, as the polymer forming the plastic, polyester (eg, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), poly(meth)acrylic (eg, polymethyl methacrylate (PMMA))) , polycarbonate (PC), polyphenylene sulfide (PPS), polystyrene, polyvinyl alcohol (PVA), polyvinyl chloride (PVC), polyvinylidene chloride, polyethylene (PE), polypropylene (PP), cyclic polyolefin ( COP), ethylene-vinyl acetate copolymer (EVA), polyimide, polyamide, polyaramid, polyethersulfone (PES), polyurethane, triacetate, triacetylcellulose (TAC), cellophane fluororesin (e.g. , polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), perfluoroalkoxyfluorine resin (PFA), tetrafluorinated ethylene/hexafluorinated propylene copolymer (FEP), ethylene/tetrafluorinated ethylene copolymer (ETFE), ethylene/chlorotrifluoroethylene copolymer (ECTFE), etc.) and composite resins containing these, etc. Among these, EVA, COP, PP, PE, PET, PPS, PEN, PC, PMMA, PES, polyimide, polyamide, aramid, PVC, and PVA are preferable.

In addition, as the shape of these substrates, for example, those in the form of films, plates, three-dimensional structures having arbitrary three-dimensional shapes, and composites thereof can be used.

In addition, any of transparent, translucent, and opaque may be sufficient as these base materials.

For example, what is in the form of a film as a transparent substrate may be an inorganic material such as thin glass or an organic material such as a plastic film as a polymer substrate. When the substrate is a plastic film, it may be an unstretched film or a stretched film depending on the type of polymer. For example, a polyester film such as a PET film is usually a biaxially stretched film, and a PC film, a triacetate film, a cellophane film, and the like are usually a non-stretched film.

As the opaque substrate, a wafer or sheet of metal, metal oxide, nitride, or carbon compound, or a polymer substrate such as polyimide, polyamide, aramid, carbon fiber, PP, PE, PET sheet, or nonwoven fabric can be used.

In addition to these substrates, functional materials such as inorganic substances such as metals, oxides, nitrides, and carbon compounds, organic substances such as low molecules and polymers, and electronic device films such as electrodes, semiconductors, and insulators formed from the composite of the above-described inorganic substances and organic substances It is also possible to form a coating film on it.

Process (C)

In step (C), the base material on which the coated film is formed is heated at a temperature of 400° C. or lower under an inert gas atmosphere to form an aluminum oxide film.

After applying the coating liquid to the surface of the substrate, the substrate is brought to a predetermined temperature and the solvent is dried, or the aluminum oxide film is formed by heating to a predetermined temperature simultaneously with drying. However, drying of the solvent has already partially progressed substantially also in the step (B). In particular, when the coating in step (B) is performed at a relatively high temperature, drying of the solvent may be almost completed in step (B).

Conditions for drying the solvent can be appropriately set according to the kind or boiling point (vapor pressure) of the coexisting organic solvent. The temperature at which the solvent is dried may be, for example, in the range of 20 to 350 ° C., when the boiling point of the solvent is 200 ° C. or less, 20 to 250 ° C., when the boiling point of the solvent is 150 ° C. or less, or 20 to 200 ° C. °C, and the drying time can be usually 0.2 to 300 minutes, preferably 0.5 to 120 minutes. These conditions can also be considered when drying the solvent at least partially in step (B). It is also possible to simultaneously perform solvent drying and aluminum oxide film formation by making the solvent drying temperature and the subsequent heating temperature for aluminum oxide film formation the same, and the temperature at that time is usually set to the heating temperature for aluminum oxide film formation. .

In the present invention, the heating temperature for forming the aluminum oxide film after solvent drying is, for example, in the range of 20 to 400°C, more preferably 20 to 350°C, and the treatment at this temperature can be performed at least once. have. The heating time at this heating temperature is usually 0.2 to 300 minutes, preferably 0.5 to 120 minutes. The heating time can be appropriately determined in consideration of the formation state of the aluminum oxide film by heating.

In particular, in the present invention, in the drying of the solvent and subsequent heat treatment, heat treatment at a low temperature of 350 ° C. or less can be used, and since the treatment can be performed in a short time, a base material having low heat resistance such as a resin is used as the base material. Functional materials such as film formation in the case of use, inorganic substances such as metals, oxides, nitrides, and carbon compounds, organic substances such as low molecules and polymers, and electronic device films such as electrodes, semiconductors, and insulators formed from the composite of the inorganic substances and organic substances described above. It becomes possible to form a film when there is a problem in the process of applying heat or high energy to the film.

Also in this process (C), it is performed under an inert gas atmosphere. By heating in step (C) under an inert gas atmosphere, 1) film formation temperature is lowered, 2) adhesion to the substrate, 3) oxide formation state (for example, transparency and homogeneity of the oxide film, etc.) It becomes possible to form an aluminum oxide film that satisfies all of the above. The inert gas atmosphere is an atmosphere made of an inert gas that does not substantially contain moisture or an oxygen source such as oxygen, and represents an atmosphere in which, for example, moisture and oxygen are respectively 1000 ppm or less, preferably 400 ppm or less. The moisture content in the inert gas atmosphere can be controlled by the dew point temperature, and if it is 400 ppm or less, it can be controlled within the range of, for example, 5 ppm (dew point temperature -66°C) to 375 ppm (dew point temperature -30°C). In addition, considering the ease of operation, it may be controlled to be in the range of 100 ppm (dew point temperature -42 ° C) to 375 ppm (dew point temperature -30 ° C).

Similarly to step (B), also in step (C), when moisture or oxygen is completely absent, in the structure of the partial hydrolyzate represented by the general formula (7), the Al-Q site becomes unreacted and the film is formed. Since there is a case where water remains in the film, the coexistence of water and oxygen is permitted within a range in which desired physical properties such as homogeneity of the resulting film are not impaired. Specifically, each of moisture and oxygen in an inert gas atmosphere can be 1000 ppm or less, preferably 400 ppm or less.

Also in step (C), in the situation where the solvent remains at the time of heating, when the moisture or oxygen in the inert gas atmosphere is greater than the above-mentioned values, the reaction between the partial hydrolyzate and the moisture and oxygen proceeds excessively, This is not preferable because deposits are powdered before formation, the transparency of the film is impaired, and the homogeneity and adhesion of the obtained aluminum oxide film are deteriorated.

Heating at 400°C or lower in step (C) forms an aluminum oxide film adhered to the substrate surface. The film thickness of the aluminum oxide film is not particularly limited, but can be practically in the range of 0.001 to 5 µm, usually 0.01 to 5 µm. According to the production method of the present invention, by repeating the coating (drying) heating process once or more, a film having a film thickness within the above range can be suitably produced. Further, in principle, it is possible to form a film of 5 μm or more by repeating the number of times of application and/or lengthening the application time.

In addition, solvent drying and heating in all methods that can be used in the present invention can be carried out either under pressure or under reduced pressure, but it is preferable to carry out under atmospheric pressure because it is convenient on the device and does not cost money.

"Aluminum oxide" obtained by the production method of the present invention is a compound containing an aluminum element and an oxygen element, and refers to a compound in which the proportion of these two elements in aluminum oxide is 90% or more. In addition to aluminum and oxygen, it may contain hydrogen or carbon. In the step (C) of the present invention, the "aluminum oxide film" produced by heating at a temperature of 400 ° C. or lower is usually in an amorphous state with no clear peak observed in X-ray diffraction analysis.

The crystallinity of the amorphous aluminum oxide film formed in step (C) can be improved by heating separately or continuously at a temperature exceeding 400°C. For example, crystallization may be performed by heat treatment at a heating temperature and treatment atmosphere in which generally known aluminum oxide at 1000° C. or higher crystallizes into crystalline alumina or the like.

Further, the aluminum oxide film obtained in step (C) is further crystallized under an oxidizing gas atmosphere such as moisture, oxygen, or ozone, under a reducing gas atmosphere such as hydrogen, or under a plasma atmosphere such as hydrogen, argon, or oxygen, as needed. It is also possible to improve sexuality.

In the composition containing a partial hydrolyzate obtained in step (A) of the production method of the present invention, (a) partial hydrolysis is performed using water having a molar ratio to the organoaluminum compound in the range of 0.4 to 1.3, (b ) This composition can be used for the formation of an aluminum oxide film in which the film is coated and formed under an inert gas atmosphere. When film formation by application and heating in an inert gas atmosphere (corresponding to steps (B) and (C)) is performed, adhesion to the substrate is excellent even at a low film formation temperature simply by coating and heating, and the oxide An aluminum oxide film in a good formation state can be formed. Adhesion to a substrate is high even for the aluminum oxide film itself obtained by using the composition for coating and forming an aluminum oxide film of the present invention, and good adhesion can be obtained even on substrates on which it is usually difficult to directly form an oxide film. However, if necessary, it is also possible to form a coating film using a method that enhances the adhesion of an oxide film formed on a substrate known in general such as undercoat treatment, priming treatment, corona treatment, UV irradiation, chlorination, or the like.

[Aluminum oxide film]

When the composition for coating and forming an aluminum oxide film of the present invention is used, an aluminum oxide film having excellent adhesion to a substrate and good oxide formation even at a low film formation temperature can be obtained simply by coating and heating in an inert gas atmosphere described above. can form

In the produced aluminum oxide film, "aluminum oxide" in the present invention refers to a compound containing an aluminum element and an oxygen element, and the ratio of these two elements to aluminum oxide is 90% or more. In addition, in the present invention, the "aluminum oxide film" produced at 400 ° C. or lower is usually in an amorphous state with no clear peak observed in X-ray diffraction analysis.

These aluminum oxide films can also be crystallized by a commonly known technique such as heating at a high temperature of 1000° C. or higher as a post-treatment after film formation, provided that the heat-resistant temperature of the substrate or the like permits.

In addition, if necessary, after the aluminum oxide film is formed, the heating is further performed under an oxidizing gas atmosphere such as oxygen or under a plasma atmosphere such as argon or oxygen to promote formation of aluminum oxide or improve crystallinity. It is also possible to do In addition, for the purpose of removing carbon components such as residual organic substances in the aluminum oxide film obtained in the present invention and improving the film quality of the aluminum oxide film, light irradiation such as ultraviolet rays or microwaves, etc., which are generally used, may be treated.

This aluminum oxide film, in the partial hydrolyzate of the organic alkyl aluminum compound contained in the composition for producing an aluminum oxide film, the molar ratio of water added so that the partial hydrolyzate is obtained with respect to the organoaluminum compound, the concentration of the partial hydrolyzate, or the coexistence Although the properties vary depending on the organic solvent, film formation conditions and methods, etc., in the coating film formation method used in the present invention, a transparent film with a high transmittance to a translucent or opaque film can be obtained, and the film thickness of the aluminum oxide film is not particularly limited. However, in practical terms, those in the range of 0.001 to 10 μm and 0.01 to 5 μm in diameter can be obtained, and a film with high adhesion to substrates such as glass and resin can be obtained.

In the production method of the present invention, the step (B) of applying the composition to the surface of the substrate and the step (C) of heating the obtained coating material are performed once or twice or more under an inert gas atmosphere. The application and heating operation of the obtained coating material can be performed appropriately the number of times necessary to obtain desired physical properties such as insulation and heat resistance, but preferably 1 to 50 times, more preferably 1 to 30 times, still more preferably It can be suitably carried out in a range of 1 time to 10 times.

[Functional film containing aluminum oxide]

The produced aluminum oxide film has excellent adhesion to the substrate and a good oxide formation state. Therefore, a composite (article) in which an aluminum oxide film is adhered to a substrate or a composite (article) in which an aluminum oxide film and a composite film having layers other than the aluminum oxide film are adhered to a substrate can be obtained. The composite film can be used as a functional film containing aluminum oxide. For example, an alumina sheet for electronic materials, production of an aluminum oxide film, production of a catalyst carrier, imparting heat resistance, imparting barrier properties to air and moisture, imparting an antireflection effect, imparting an antistatic effect, imparting an antifogging effect, imparting abrasion resistance, etc. , it can be used for applications such as a binder for ceramic production. Specifically, protective films for mechanical parts and cutting tools, semiconductors, magnetic materials, insulating films such as solar cells, dielectric films, antireflection films, surface devices, magnetic heads, sensor elements such as infrared rays, and packaging materials such as food, medicine, and medical equipment materials. barrier films against air and moisture, various powders, films, films made of glass or plastic, coating films on substrates such as molded bodies, and heat-resistant materials and high-hardness films using these, optical members, binders for ceramic production, etc. It can be applied as part or all of functional films capable of imparting various functionalities to substrates such as aluminum oxide films used for applications.

[substrate provided with aluminum oxide film and substrate provided with functional film containing aluminum oxide]

In addition, the substrate provided with these aluminum oxide films or functional films containing aluminum oxide is a heat-resistant material such as a heat-resistant film, an insulating material, a material such as a barrier film to moisture or oxygen, an antireflection film, an antireflection material such as glass, It can be used as a high-hardness film or material.

<Third aspect of the present invention>

<Method for manufacturing article provided with aluminum oxide film>

The manufacturing method of the article provided with the aluminum oxide film of this invention includes the following process (A) and (B).

Step (A) A step of spraying an organic solvent solution of an organic aluminum compound represented by the following general formula (6) or a partial hydrolyzate thereof onto at least a part of the surface of a substrate to form a coating film;

(Wherein, R ¹ represents hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and R ² and R ³ are independently hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, or a linear or branched alkyl group having 1 to 7 carbon atoms) or a branched alkoxyl group, acyloxy group or acetylacetonate group.)

(B) A step of heating the base material on which the coated film is formed at a temperature of 400° C. or lower in an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture to form an aluminum oxide film from the coated film.

Process (A)

Step (A) is a step of forming a coating film by spraying an organic solvent solution of an organoaluminum compound represented by formula (6) onto at least a part of the surface of a substrate (hereinafter referred to as step (A1)), or This is a step of forming a coating film by spraying an organic solvent solution of a partial hydrolyzate of an organoaluminum compound represented by the general formula (6) on at least a part of the surface of the substrate (hereinafter referred to as step (A2)).

The organoaluminum compound represented by the general formula (6) is the same as the organoaluminum compound represented by the general formula (6) in the second aspect of the present invention, refer to the description in the second aspect of the present invention. .

Alkyl aluminum such as triisobutylaluminum, trin-butylaluminum, trihexylaluminum, and trioctylaluminum, aluminum triisopropoxide, aluminum sec-butoxide, and aluminum tert-butoxide within a range that does not interfere Aluminum compounds such as alkoxides such as alkoxides, β-diketonate complexes such as aluminum acetylacetonate, and inorganic salts such as aluminum acetate and aluminum hydroxide may coexist in the solution used in the present invention.

Solution for spray application used in step (A1)

The solution for spray coating used in step (A1) is a solution obtained by dissolving the organoaluminum compound represented by the general formula (6) in an organic solvent. Since the organoaluminum compound represented by the general formula (6) is used without hydrolysis in step (A1), it is appropriate that R ¹ is a straight-chain or branched alkyl group having 1 to 3 carbon atoms.

It is suitable that the organic solvent is an organic solvent having electron donating property from the viewpoint of having solubility for the organoaluminum compound represented by the general formula (6). The organic solvent having electron donating property should just have solubility with respect to the organoaluminum compound represented by General formula (6).

Examples of the electron-donating organic solvent include 1,2-diethoxyethane, 1,2-dibutoxyethane, diethyl ether, din-propyl ether, diisopropyl ether, dibutyl ether, and cyclophenylmethyl. Ether solvents such as ether, tetrahydrofuran, dioxane, glyme, diglyme, triglyme, anisole, and methoxytoluene, amine solvents such as trimethylamine, triethylamine, and triphenylamine can be heard As the electron-donating solvent, 1,2-diethoxyethane, tetrahydrofuran, and dioxane are preferable.

In step (A1), a hydrocarbon compound can be used as a solvent that can coexist with the electron-donating organic solvent, and in step (A1), a mixture of an electron-donating organic solvent and a hydrocarbon compound can also be used as the organic solvent. As the above-mentioned hydrocarbon compounds, straight-chain or branched hydrocarbon compounds or cyclic hydrocarbon compounds having 5 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, aromatic hydrocarbon compounds having 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, and these A mixture of can be exemplified. Specific examples of hydrocarbon compounds include pentane, n-hexane, heptane, isohexane, methylpentane, octane, 2,2,4-trimethylpentane (isooctane), n-nonane, n-decane, n-hexadecane, aliphatic hydrocarbons such as octadecane, eicosan, methylheptane, 2,2-dimethylhexane, and 2-methyloctane; Alicyclic hydrocarbons such as cyclopentane, cyclohexanemethylcyclohexane, and ethylcyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, cumene, and trimethylbenzene, mineral spirits, hydrocarbons such as solvent naphtha, kerosene, and petroleum ether A solvent can be mentioned.

The concentration of the organoaluminum compound represented by the general formula (6) in the spray coating solution used in step (A1) is within the range of 0.1 to 35% by mass from the viewpoint of easy control of reactivity. It is suitable. The higher the concentration, the smaller the number of coatings, but the higher the reactivity of the organic aluminum compound having an alkyl group of 1 to 3 carbon atoms, making it difficult to handle other than when forming the film. Therefore, usually, the upper limit of the concentration becomes a problem, and the concentration of the compound is preferably 0.1 to 25% by mass, more preferably 0.1 to 15% by mass, and still more preferably 0.1 to 12% by mass.

Solution for spray application used in step (A2)

The spray coating solution used in step (A2) is an organic solvent solution of a partial hydrolyzate of an organoaluminum compound represented by the general formula (6). The organic aluminum compound represented by General Formula (6) is as described above. As the organic solvent, any of hydrocarbon compounds, electron-donating organic solvents and mixtures thereof can be used. The hydrocarbon compound and the electron-donating organic solvent are the same as those described in step (A1).

A partial hydrolyzate is a substance obtained by partially hydrolyzing the organoaluminum compound represented by the general formula (6) in an organic solvent using water at a molar ratio of 0.7 or less. If it is a partial hydrolyzate using water at a molar ratio of 0.7 or less, it is spray-coated in the same way as the spray coating solution (organoaluminum compound not partially hydrolyzed) used in step (A1), and then passed through step (B), An aluminum oxide film can be produced. Partial hydrolysis is performed by adding water to a solution in which the compound represented by the general formula (6) is dissolved in an organic solvent, or by mixing the organic solvent solution of the compound represented by the general formula (6) with water. The amount of water added is preferably within the range of 0.6 or less for the molar ratio with respect to the organoaluminum compound, since spraying can be applied similarly to the spray coating solution (organoaluminum compound not partially hydrolyzed) used in step (A1). . Although there is no lower limit to the amount of water added, it can be, for example, 0.05 or more, preferably 0.1 or more, since addition of a small amount of water only makes the operation complicated as long as the step of partial hydrolysis is given.

The concentration of the compound represented by the general formula (6) in the solution is appropriately determined in consideration of the solubility in the organic solvent and the concentration of the partial hydrolyzate in the obtained partial hydrolyzate, etc., for example, 0.1 to 50% by mass It is suitable to set it as a range, and the range of 0.1-35 mass % is preferable.

Addition or mixing of water may be performed without mixing water with other solvents, or may be performed after mixing water with other solvents. The addition or mixing of water can be performed over a period of time from 60 seconds to 10 hours, depending on the scale of the reaction. From a viewpoint that the yield of a partial hydrolyzate is favorable, it is preferable to add water to the organoaluminum compound of General formula (6) which is a raw material by dripping. Addition of water can be performed, for example, without stirring (in the state left still) or while stirring the solution of the compound represented by General formula (6) and an organic solvent, for example, an electron-donating organic solvent. As the temperature during addition, an arbitrary temperature between -90 and 150°C can be selected. It is -15 to 30 degreeC is preferable from a viewpoint of the reactivity of water and an organoaluminum compound.

After the addition of water, in order to further advance the hydrolysis reaction between water and the compound represented by the general formula (6), for example, from 1 minute to 48 hours, leave without stirring (in a state of standing) or stir. can Regarding the reaction temperature, the reaction can be carried out at an arbitrary temperature between -90 and 150°C. It is -15 to 80 degreeC is preferable from a viewpoint of obtaining a partial hydrolyzate in high yield. The pressure in the hydrolysis reaction is not limited. Usually, it can be carried out at normal pressure (atmospheric pressure).

The progress of the hydrolysis reaction between water and the compound represented by the general formula (6) can be monitored, if necessary, by sampling the reaction mixture, analyzing the sample by NMR or IR, or sampling the generated gas. have.

The organic solvent, the organic aluminum compound of the general formula (6) as a raw material, and water can be introduced into the reaction vessel in accordance with any conventional method, and the organic aluminum compound and water can be introduced as a mixture with the organic solvent, respectively. . The hydrolysis reaction step may be any of a batch operation type, a semi-batch operation type, and a continuous operation type, and is not particularly limited, but a batch operation type is preferable.

By the above hydrolysis reaction, the organic aluminum compound of the general formula (6) is partially hydrolyzed with water, so that a product containing a partial hydrolyzate can be obtained. In the case where the organoaluminum compound of the general formula (6) is trimethylaluminum, triethylaluminum or the like, analysis of the hydrolyzate has been performed for a long time. However, the results differ depending on the report, and the composition of the product is not clearly specified. Also, the composition of the product may be changed by the molar ratio of addition of water or the reaction time. The main component of the product in the method of the present invention is a partial hydrolyzate, and it is assumed that the partial hydrolyzate is a mixture of compounds containing structural units represented by the following general formula (7), as in the second aspect of the present invention. do:

(In the formula, Q is the same as any one of R ¹ , R ² , and R ³ in the general formula (6), and m is an integer from 1 to 200.)

After completion of the hydrolysis reaction, some or all of the product may be recovered and/or purified by general methods such as filtration, concentration, extraction, column chromatography, and the like. Under conditions where the molar ratio of water to organoaluminium compound of the general formula (6) is relatively high, insoluble matter may be generated. , it is desirable to obtain a composition containing a partially hydrolyzate substantially free of insoluble matter.

The partial hydrolyzate (solid content) separated from the organic solvent and recovered by the above method can be dissolved in an organic solvent for spray coating different from the organic solvent used for the reaction to make a composition for spray coating. However, without separation from the organic solvent, the reaction product mixture, which is a partially hydrolyzate-containing material, may be used as a solution for spray coating as it is or after appropriately adjusting the concentration.

Examples of organic solvents usable as organic solvents for spray coating include straight-chain and branched hydrocarbon compounds or cyclic hydrocarbon compounds having 5 to 20 carbon atoms, more preferably 6 to 12 carbon atoms, and 6 to 20 carbon atoms, more preferably 6 to 12 carbon atoms. 6 to 12 aromatic hydrocarbon compounds and mixtures thereof can be exemplified.

As specific examples of these hydrocarbon compounds, pentane, n-hexane, heptane, isohexane, methylpentane, octane, 2,2,4-trimethylpentane (isooctane), n-nonane, n-decane, n-hexadecane aliphatic hydrocarbons such as octadecane, eicosan, methylheptane, 2,2-dimethylhexane, and 2-methyloctane; Alicyclic hydrocarbons such as cyclopentane, cyclohexanemethylcyclohexane, and ethyl cyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, cumene, and trimethylbenzene, mineral spirits, hydrocarbons such as solvent naphtha, kerosene, and petroleum ether A solvent can be mentioned.

Other examples of organic solvents that can be used as organic solvents for spray coating include 1,2-diethoxyethane, 1,2-dibutoxyethane, diethyl ether, din-propyl ether, and diisopropyl. Ether solvents such as ether, dibutyl ether, cyclopentylmethyl ether, tetrahydrofuran, dioxane, glyme, diglyme, triglyme, anisole, methoxytoluene, trimethylamine, triethylamine, Amine solvents, such as triphenylamine, etc. are mentioned.

In addition, these organic solvents are not only used individually, but also can be used in mixture of two or more types.

Further, in the spray coating solution, when R ¹ , R ² , R ³ remaining in the solution after hydrolysis is an alkoxide group, as a solvent that can coexist in the composition, methanol, ethanol, n-propyl alcohol, Alcohols such as isopropyl alcohol, isobutyl alcohol, n-butyl alcohol, and diethylene glycol can also be used as organic solvents for spray coating.

The solid content concentration of the partial hydrolyzate of the composition containing the partial hydrolyzate used in step (A2) may be, for example, in the range of 0.1 to 30% by mass. Although the higher the concentration, the film can be produced with fewer coatings. However, considering the solubility of the reaction product including the partial hydrolyzate of the organoaluminum compound, for example, the ease of formation of the aluminum oxide film, it is preferably 0.1 to 25 % by mass, more preferably 0.1 to 15% by mass.

The spray coating solution containing the partial hydrolyzate used in the step (A2) corresponds to the composition for coating an aluminum oxide film of the present invention.

<About spray application>

Spray coating is common in Step (A1) and Step (A2).

In the spray application, spray application is performed on at least a part of the surface of the substrate using a solution for spray application. By spraying, a coating film of the spray coating solution is formed. Although spray application can be carried out at normal temperature (room temperature), it can also be carried out under heating as described later. In addition, spray coating is performed in an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture.

The reason why spray coating is performed in an inert gas atmosphere is that the organoaluminum compound and/or partial hydrolyzate contained in the spray coating solution reacts with moisture in the atmosphere to gradually decompose, and to form an aluminum oxide film. Regarding the solution, it is to deal with the viewpoint of facilitating film formation control under conditions where water coexists, and flammable solvents. Although there is no limitation in particular about an inert gas, For example, helium, argon, nitrogen, etc. are mentioned. Among these, nitrogen is particularly preferable in terms of cost. Regarding the pressure at the time of application, any of atmospheric pressure, pressurized pressure, and reduced pressure can be applied, but it is usually preferable to carry out the application at atmospheric pressure because it is convenient on the device and does not cost money.

In addition, the inert gas atmosphere containing 0.5 mol% - 30 mol% of water|moisture content is used for an inert gas atmosphere. In the spray coating, for example, in the space until the spray coating solution such as the spray coating method, the spray pyrolysis method, the electrostatic coating method, and the inkjet method reaches the substrate by spraying, an oxygen source such as water and the like coexist Formation of aluminum oxide by the reaction of the easy spray coating method is used. At that time, when the inert gas atmosphere contains 0.5 mol% to 30 mol% of water, the hydrolysis reaction proceeds in the space until it is sprayed and reaches the substrate, and the subsequent generation of the aluminum oxide thin film becomes smooth. . From the viewpoint of smoother production of the aluminum oxide film thin film, the water content of the inert gas atmosphere is preferably 1 mol% to 25 mol%. As an example of the inert gas containing this specific moisture, for example, as an inert gas containing 0.5 mol% of moisture, a dew point of -2 ° C., 21% as a relative humidity at 21 ° C. Inert gas is exemplified, As an inert gas containing 1 mol% of water, a dew point of 8°C and a relative humidity at 21°C can be 43% of an inert gas, and as an inert gas containing 25 mol% of water, 65°C It can be exemplified by containing saturated water vapor of

Although there is no limitation in particular about an inert gas, For example, helium, argon, nitrogen, etc. are mentioned. Among these, nitrogen is particularly preferable in terms of cost. Although the spray application to the surface of the substrate can be carried out either under pressure or under reduced pressure, it is preferable to carry out the application under atmospheric pressure because it is convenient on the device as well.

As a method of spray application, for example, spray application, spray pyrolysis method, electrostatic coating method, ink jet method and the like can be used. The spray pyrolysis method and the electrostatic coating method are methods in which coating and film formation can be performed simultaneously while heating the substrate, and therefore, the solvent can be dried in parallel with the coating, and depending on the conditions, heating for drying the solvent is unnecessary. Sometimes. In addition, depending on the conditions, in addition to drying, at least a part of the reaction of the partial hydrolyzate of the organic aluminum compound to aluminum oxide may also proceed. Therefore, in some cases, the aluminum oxide film formation by heating at a predetermined temperature, which is a later step, can be performed more easily.

Process (B)

In step (B), the base material on which the coated film is formed is heated at a temperature of 400 ° C. or less in an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture, and an aluminum oxide film is formed from the coated film. The inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture is the same as that described in step (A).

The heating temperature can be appropriately selected depending on the composition of the coating liquid, the spray coating method, and the type of substrate. However, it is performed at a temperature of 400°C or lower. Depending on the type of substrate, it is also possible to form an aluminum oxide film by heating at a temperature exceeding 400°C, but in the present invention, an aluminum oxide film having sufficiently good physical properties is formed by heating at a temperature of 4400°C or less. can do.

In addition, depending on the type of spray application method, the atmosphere and/or substrate may be heated even during application in step (A). In this case, it is preferable to make the coating and heating temperatures the same because operation is simple. The atmosphere at the time of coating and film formation in spray coating and/or the heating temperature of the substrate may be, for example, in the range of 50 to 400°C, preferably 100 to 400°C. In particular, in the present invention, film formation in the case of using a substrate with low heat resistance such as resin for the substrate, inorganic materials such as metals, oxides, nitrides, and carbon compounds, organic materials such as low molecules and polymers, and composites of the above-mentioned inorganic materials and organic materials It is possible to form a film when there is a problem in the process of applying heat or high energy to functional materials such as electronic device films such as electrodes, semiconductors, and insulators to be formed, and the range of 50 to 350 ° C is preferable, and 100 It is more preferable to carry out in the range of -300 degreeC.

3A shows a spray film forming device as an example of a film forming device by spray coating used in the present invention. In the figure, (1) is a spray bottle filled with a coating liquid, (2) is a substrate holder, (3) is a spray nozzle, (4) is a compressor, (5) is a substrate, and (6) is a tube for introducing water vapor. indicate In spray application, a substrate is installed in the substrate holder 2, heated to a predetermined temperature using a heater as necessary, and then a spray nozzle disposed above the substrate in an inert gas atmosphere (under atmospheric pressure). The inert gas compressed from (3) and the coating liquid are simultaneously supplied, the coating liquid is atomized and sprayed, and water is introduced from the water vapor introduction tube 6 to coexist in the film formation atmosphere, thereby aluminum oxide on the substrate. A thin film can be formed. In the case of spray application under heating, an aluminum oxide film may be formed without additional heating or the like.

In the spray application of the coating liquid, it is preferable to discharge the coating liquid from the spray nozzle so that the size of the droplet is in the range of 30 μm or less, considering the adhesion to the substrate and the ease of evaporation of the solvent. In addition, considering that the organic solvent evaporates for some time until it reaches the substrate from the spray nozzle and the size of the droplet decreases, etc., the distance between the spray nozzle and the substrate is 50 cm or less to produce an aluminum oxide film. desirable from the point of view

A film formation method by spray application such as a spray pyrolysis method or an electrostatic coating method is a method in which coating and film formation can be performed simultaneously while heating a substrate, and therefore, an organic solvent can be dried simultaneously with application, depending on conditions. In some cases, heating for drying the solvent is unnecessary. Depending on the conditions, in addition to drying, at least a part of the reaction of the partial hydrolyzate of the organoaluminum compound with respect to aluminum oxide may also proceed. Therefore, in some cases, the aluminum oxide film formation by heating at a predetermined temperature, which is a later step, can be performed more easily. The heating temperature of the substrate at the time of application and film formation in the spray pyrolysis method may be, for example, in the range of 50 to 400°C, preferably 100 to 400°C. In particular, when a substrate having low heat resistance such as a resin is used as the substrate, the heating can be carried out in a range of 50 to 350°C, preferably in a range of 50 to 350°C.

In addition, after spraying the spray coating solution on the surface of the substrate in step (A), if necessary, setting the base material to a predetermined temperature to dry the solvent, and then heating to a predetermined temperature in step (B) An aluminum oxide film may be formed by.

The drying temperature of the organic solvent in step (A) may be, for example, in the range of 20 to 200°C, and may be appropriately set depending on the type of organic solvent coexisting. The heating temperature for forming the aluminum oxide film after drying the solvent is as described above.

In the film formation by spray coating of the present invention, it is possible to simultaneously perform solvent drying and aluminum oxide film formation by making the solvent drying temperature and the subsequent heating temperature for aluminum oxide film formation the same, and the temperature at that time is It is set to the heating temperature of the range mentioned above in (B).

On the other hand, spraying and heating in the present invention can be carried out either under pressure or under reduced pressure, but it is preferable to carry out under atmospheric pressure because it is convenient and cost-free even on equipment.

In the above manufacturing method, as a substrate for forming the aluminum oxide film, there are inorganic materials such as glass, metal and ceramics, polymer substrates such as plastic, organic materials such as paper and wood, and composites thereof.

Specific examples of these descriptions are the same as those described in the second aspect of the present invention.

When film formation is performed by spray coating using the solution for producing an aluminum oxide film of the present invention, even if the film formation temperature is low, an aluminum oxide film having excellent adhesion to a substrate and a good oxide formation state can be obtained simply by coating and heating. can form The aluminum oxide film itself obtained by using the aluminum oxide production solution of the present invention has high adhesion to the substrate, and usually, good adhesion is obtained even on substrates on which direct oxide film formation is difficult, but if necessary, undercoat treatment and primer It is also possible to form a coating film using a generally known method such as treatment, corona treatment, UV irradiation, chlorination, or the like to improve the adhesion of an oxide film formed on a substrate.

[Aluminum Oxide and Aluminum Oxide Film]

If film formation is performed by spray coating using the solution for producing an aluminum oxide film of the present invention, an aluminum oxide film having excellent adhesion to a substrate and good oxide formation even at a low film formation temperature can be obtained simply by coating and heating. can form

As for the produced aluminum oxide film, "aluminum oxide" in the present invention refers to a compound containing an aluminum element and an oxygen element, and the proportion of these two elements in aluminum oxide is 90% or more. In addition to aluminum and oxygen, it may contain hydrogen or carbon. In addition, in the present invention, the "aluminum oxide film" produced at 500 ° C. or lower is usually in an amorphous state with no clear peak observed in X-ray diffraction analysis.

These aluminum oxide films can also be crystallized by a commonly known technique such as heating at a high temperature of 1000° C. or higher as a post-treatment after film formation, provided that the heat-resistant temperature of the substrate or the like permits. That is, if necessary, after the aluminum oxide film is formed in step (B), the formation of aluminum oxide is further promoted by performing the above heating under an oxidizing gas atmosphere such as oxygen or under a plasma atmosphere such as argon or oxygen. , or, it is also possible to improve the crystallinity. In addition, for the purpose of removing carbon components such as residual organic matter in the aluminum oxide film obtained in the present invention and improving the film quality of the aluminum oxide film, light irradiation such as ultraviolet light or microwave treatment may be performed. The film thickness of the aluminum oxide film is not particularly limited, but may be, for example, in the range of 0.005 to 5 μm, more practically in the range of 0.001 to 5 μm. According to the production method of the present invention, by repeating the coating (drying) heating process once or more, a film having a film thickness within the above range can be suitably manufactured. Further, in principle, it is possible to form a film having a thickness of 5 μm or more by repeating the number of times of application or lengthening the application time. In the manufacturing method of the present invention, the step (A) of applying the spray coating solution to the surface of the substrate under an inert gas atmosphere and the step (B) of heating the obtained coating material are performed once or twice or more. The coating and heating operation of the obtained coating material can be performed appropriately as many times as necessary to obtain desired physical properties such as insulation and heat resistance, but is preferably 1 to 50 times, more preferably 1 to 30 times, still more preferably It can be suitably carried out within a range of 1 time to 10 times. In the spray coating method used in the present invention, transparent to translucent and opaque materials with high transmittance can be obtained. A film having high adhesion to a base material such as glass or resin can be obtained.

[Functional film containing aluminum oxide]

The produced aluminum oxide film has excellent adhesion to the substrate and a good oxide formation state. Therefore, a composite (article) in which an aluminum oxide film is adhered to a substrate or a composite (article) in which an aluminum oxide film and a composite film having layers other than the aluminum oxide film are adhered to a substrate can be obtained. The composite film can be used as a functional film containing aluminum oxide. For example, an alumina sheet for electronic materials, production of an aluminum oxide film, production of a catalyst carrier, imparting heat resistance, imparting barrier properties to air and moisture, imparting an antireflection effect, imparting an antistatic effect, imparting an antifogging effect, imparting abrasion resistance, etc. , it can be used for applications such as a binder for ceramic production. Specifically, protective films for mechanical parts and cutting tools, semiconductors, magnetic materials, insulating films such as solar cells, dielectric films, antireflection films, surface devices, magnetic heads, sensor elements such as infrared rays, and packaging materials such as food, medicine, and medical equipment materials. Barrier film against air and moisture, various powders, films, films made of glass or plastic, coating films for substrates such as molded bodies, and heat-resistant materials or high-hardness films using these materials, optical members, binders for ceramic production, etc. It can be applied as part or all of a functional film capable of imparting various functionalities to a base material, such as an aluminum oxide film used for .

[substrate provided with aluminum oxide film and substrate provided with functional film containing aluminum oxide]

In addition, the base material provided with these aluminum oxide films or functional films containing aluminum oxide is a heat-resistant material such as a heat-resistant film, an insulating material, a material such as a barrier film to moisture or oxygen, an antireflection film, an antireflection material such as glass, It can be used as a high-hardness film or material.

[Composition for producing aluminum oxide film]

The present invention includes a composition for forming an aluminum oxide film.

The first aspect of this composition is a film-forming composition comprising an organic solvent solution of an organoaluminum compound represented by the above general formula (6), wherein the composition is formed by applying a film to a water content of 0.5 mol% to 30 mol%. It is the said composition which is for using for formation of the aluminum oxide film performed in the containing inert gas atmosphere.

The second aspect of the composition is a composition for film formation containing a partial hydrolyzate of the organoaluminum compound represented by the general formula (6) obtained by partially hydrolyzing the organoaluminum compound in an organic solvent,

(a) The partial hydrolysis is carried out using water having a molar ratio to the organoaluminum compound of 0.7 or less, and

(b) The above composition is the above composition for use in forming an aluminum oxide film in which film coating is performed under an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture.

The composition of the first aspect is described as a spray coating solution in step (A1). The composition of the second aspect is described as a spray coating solution in step (A2).

The film coating formation performed in an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture,

(c1) forming a coating film by spraying the composition on at least a part of the surface of a substrate under an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture; and

(c2) forming an aluminum oxide film by heating the substrate on which the coated film is formed at a temperature of 400° C. or less under an inert gas atmosphere containing 0.5 mol% to 30 mol% of moisture. These steps are as described above as steps (A) and (B).

The composition of the present invention is a composition used to form a transparent aluminum oxide film adhered to a substrate.

<Fourth aspect of the present invention>

[Alkyl Aluminum Containing Solution]

The first aspect of the fourth aspect of the present invention is an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (provided that the alkyl group of dialkyl aluminum and trialkyl aluminum has 1 to 6 carbon atoms, and the same or A solution containing an alkyl aluminum compound containing an organic solvent having electron donating property and not containing active hydrogen atoms is applied to a substrate as droplets having an average particle diameter of 3 to 30 μm in air to form a coating film. and heating the formed coating film to aluminum oxide after drying the organic solvent or in parallel with drying the organic solvent.

The solution containing an alkyl aluminum compound of the present invention chemically stabilizes an alkyl aluminum compound, which is dialkyl aluminum, trialkyl aluminum, or a mixture thereof, by containing an organic solvent having electron donating property and not containing an active hydrogen atom as an organic solvent. can make it The reason why an organic solvent having electron donating property and not containing an active hydrogen atom is preferable is not clear, but it is presumed that the reactivity to water is made appropriate by the coordination bond of the unshared electron pair of oxygen in the structure to aluminum.

The ratio of the alkyl aluminum compound in the solution of the present invention to the organic solvent having the electron donating property and not containing an active hydrogen atom depends on the alkyl aluminum compound from the viewpoint of keeping the alkyl aluminum compound chemically stable. It is preferable to contain an organic solvent having an electron donating property of 1 or more in terms of mole ratio and not containing an active hydrogen atom. Chemical changes such as spontaneous combustion of the solution can be suppressed and reactivity to water can be appropriately made by containing an organic solvent having an electron donating property of 1 or more in molar ratio with respect to the alkyl aluminum compound and not containing an active hydrogen atom.

The active hydrogen atom means a highly reactive hydrogen atom bonded to an atom of an element other than a carbon atom, such as a nitrogen atom, an oxygen atom, or a sulfur atom, among hydrogen atoms in a molecule of an organic compound.

Examples of the organic solvent having electron donating property and not containing an active hydrogen atom include diethyl ether, tetrahydrofuran, t-butylmethyl ether, din-propyl ether, diisopropyl ether, and 1,4-dioxane. , ether compounds such as 1,3-dioxalane, dibutyl ether, cyclopentylmethyl ether, and anisole; ethylene glycol dialkyl ether compounds such as 1,2-dimethoxyethane, 1,2-diethoxyethane, and 1,2-dibutoxyethane; Diethylene glycol dialkyl ether compounds such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol dibutyl ether; triethylene glycol dialkyl ether compounds such as ether and triethylene glycol diethyl ether; propylene glycol dialkyl compounds such as propylene glycol dimethyl ether; Dipropylene glycol dialkyl, such as dipropylene glycol dimethyl; tripropylene glycol dialkyl compounds such as tripropylene glycol dimethyl; ester compounds such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, sec-butyl acetate, pentyl acetate, methoxybutyl acetate, amyl acetate, and cellosolve acetate; amide compounds such as N,N-dimethylformamide; N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone, etc. Cyclic amide compounds of; carbonate compounds such as ethylene carbonate, propylene carbonate, dimethyl carbonate and diethyl carbonate, or mixtures thereof.

Alcoholic solvents such as ethanol, isopropanol, and butanol, and carboxylic acid solvents such as formic acid, acetic acid, and propionic acid all have active hydrogen atoms, so they are not organic solvents that have the electron donating ability and do not contain active hydrogen atoms. .

A conjugated diketone such as acetylacetone is an enolate compound and generates active hydrogen atoms, so it is not an organic solvent that has the electron donating ability and does not contain active hydrogen atoms.

In the dialkyl aluminum and/or trialkyl aluminum, the alkyl groups of the dialkyl aluminum and the trialkyl aluminum have 1 to 6 carbon atoms, and the plurality of alkyl groups of one dialkyl aluminum or one trialkyl aluminum may be the same. Or they may be different.

The dialkyl aluminum refers to a trivalent aluminum compound in which two ligands are alkyl groups and one is a non-alkyl group, and the trialkyl aluminum refers to a trivalent aluminum compound in which all three ligands are alkyl groups.

Dialkyl aluminum and/or trialkyl aluminum may be, for example, an alkyl aluminum compound represented by the general formula (8) or (9):

(In the formula, R ¹ represents a methyl group or an ethyl group.)

(In the formula, R ² represents an isobutyl group, and R ³ represents hydrogen or an isobutyl group.)

As an example of the compound represented by General formula (8), trimethyl aluminum, triethyl aluminum, etc. are mentioned.

Triisobutyl aluminum, diisobutyl aluminum hydride, etc. are mentioned as an example of the compound represented by General formula (9).

The dialkyl aluminum and/or the trialkyl aluminum is preferably triethyl aluminum or triisobutyl aluminum from the viewpoint of low cost per unit mass of aluminum.

The concentration of the alkyl aluminum compound in the alkyl aluminum-containing solution used in the production method of the present invention may be, for example, 1% by mass or more and 20% by mass or less. In the case of the alkyl aluminum compound represented by the general formula (8), 1 mass% or more and 10 mass% or less, and in the case of the alkyl aluminum compound represented by the general formula (9), 1 mass% or more and 20 mass% or less it is desirable Since productivity of a film|membrane will fall when it is less than 1 mass %, it is preferable that it is 1 mass % or more. The concentration of the alkyl aluminum compound in the alkyl aluminum-containing solution affects the risk of ignition, etc., especially in the production of aluminum oxide by application in air. It has the advantage of being able to manufacture.

The alkyl aluminum-containing solution used in the production method of the present invention is an organic solvent other than an organic solvent that has electron donating property and does not contain active hydrogen atoms, and does not have electron donating property and does not contain active hydrogen atoms. may further include. Polarity, viscosity, boiling point, economy, etc. can be adjusted by adding an organic solvent that does not have electron donating property and does not contain active hydrogen atoms. Examples of organic solvents that do not have electron donating property and do not contain active hydrogen atoms include aliphatic hydrocarbons such as n-hexane, octane, and n-decane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane, and ethylcyclohexane; Aromatic hydrocarbons, such as benzene, toluene, xylene, and cumene; Hydrocarbon solvents, such as mineral spirits, solvent naphtha, kerosene, and petroleum ether, etc. are mentioned. The addition amount of the organic solvent having no electron donating property and not containing an active hydrogen atom is not limited as long as it does not interfere with the effect of the organic solvent having electron donating property and not containing an active hydrogen atom. For example, It can be 100 parts by mass or less with respect to 100 parts by mass of an organic solvent that has electron donating property and does not contain active hydrogen atoms. However, the range that can be added varies depending on the type of the alkyl aluminum compound, the organic solvent that has electron donating property and does not contain active hydrogen atoms, and the type of organic solvent that does not have electron donating property and does not contain active hydrogen atoms. . Further, in the solution containing the alkyl aluminum compound, the alkyl aluminum compound in the solution containing the alkyl aluminum compound is chemically stabilized by containing an organic solvent having an electron donating property of 1 or more in terms of molar ratio to the alkyl aluminum compound and not containing an active hydrogen atom. can make it Therefore, when an organic solvent that does not have electron donating property and does not contain an active hydrogen atom is used in combination, it is preferable to determine the combined amount in consideration of this point.

Mixing of the organic solvent having the above electron-donating property and not containing active hydrogen atoms, and, if necessary, the organic solvent having no electron-donating property and not containing active hydrogen atoms, with an alkyl aluminum compound is a reaction under an inert gas atmosphere. It can be carried out in a container, and each can be introduced according to any conventional method. The alkyl aluminum compound can be introduced into the reaction vessel even as a mixture with an organic solvent that does not have electron donating property and does not contain an active hydrogen atom.

The order of introduction into the mixing vessel is the order of an alkyl aluminum compound, an organic solvent having electron donating property and not containing an active hydrogen atom, and, if necessary, an organic compound having no electron donating property and not containing an active hydrogen atom. , or an organic solvent having electron donating property and not containing an active hydrogen atom, and, if necessary, an organic solvent having no electron donating property and not containing an active hydrogen atom, an alkyl aluminum in that order, or both of them being introduced at the same time. any of these may be

The introduction time into the mixing vessel can be appropriately set depending on the type and capacity of the raw materials to be mixed, but can be, for example, between 1 minute and 10 hours. Any temperature between -15 and 150°C can be selected as the temperature at the time of introduction. However, considering safety such as excluding the risk of ignition at the time of introduction, it is preferably in the range of -15 to 80 ° C.

At the time of introducing the raw material into the mixing vessel, the stirring step after the introduction may be any of a batch operation type, a semi-batch operation type, and a continuous operation type.

[Method for producing aluminum oxide thin film]

The method for producing an aluminum oxide thin film of the present invention comprises applying the above alkyl aluminum compound-containing solution to a substrate to form a coating film, and heating the formed coating film after drying an organic solvent or in parallel with drying the organic solvent. This is a method of obtaining an aluminum oxide thin film by making it aluminum oxide.

The application of the alkyl aluminum compound-containing solution to the substrate is preferably carried out by a method such as a spray coating method, an electrostatic spray coating method, an inkjet method, or a mist CVD method, and a spray coating method is more preferable because the apparatus is simpler. .

The application of the alkyl aluminum compound-containing solution to the substrate is performed in an air atmosphere from the viewpoint of economy. Performing in an air atmosphere is preferable because the apparatus is also simplified.

Although the application of the solution containing an alkyl aluminum compound to the substrate can be carried out either under pressure or under reduced pressure, from the viewpoint of economic efficiency, it is preferable to carry out the application under atmospheric pressure because the apparatus is simple.

The application of the alkyl aluminum compound-containing solution to the substrate is performed by applying the alkyl aluminum-containing solution to the substrate as droplets having an average particle diameter of 1 to 100 μm. When droplets of an alkyl aluminum compound-containing solution with an average particle diameter of less than 1 μm are used, the efficiency of use of the material (adhesion efficiency to the substrate) decreases, and when droplets with an average particle diameter of more than 100 μm are used, the film formed by application is reduced. The average particle size of the alkyl aluminum-containing solution is limited to the above range because the properties (particularly, compactness) are lowered. When the alkyl aluminum-containing solution is applied to a substrate in droplets having an average particle diameter of 3 to 30 μm, the material use efficiency (adhesion efficiency to the substrate) is high, and the properties of the film formed by application (particularly, compactness) are good It is desirable from the point of view of For example, by passing an alkyl aluminum-containing solution through a spray nozzle for precision cloth, it can be made into droplets of 1 to 100 μm. The spray nozzle is preferably a two-fluid nozzle, and the droplets are preferably 3 to 30 μm. When it is 3 μm or more, the adhesion efficiency of droplets to the substrate is improved, and when it is 30 μm or less, film characteristics (transparency, in-plane uniformity, and compactness) become better.

In the case of coating, it is preferable to carry out with the distance of a spray nozzle and a base material within 50 cm, and also more preferably within 20 cm. When the size of the droplet is greater than 50 cm, the solvent in the droplet dries until it reaches the substrate, and the size of the droplet decreases, reducing the adhesion efficiency of the droplet to the substrate.

It is preferable that the atmospheric temperature at the time of application|coating is 50 degreeC or less.

The humidity of the air may be, for example, an air atmosphere containing 20 to 90% of water at a relative humidity converted to 25°C. The relative humidity converted to 25°C is more preferably 30 to 70% from the viewpoint of smooth formation of the aluminum oxide thin film.

The substrate is not particularly limited as long as it is a substrate on which it is desired to form an aluminum oxide thin film. Specific examples of the above description are the same as those described in the first aspect of the present invention.

The shape of the substrate may include a powder, film, plate, or a three-dimensional structure having a three-dimensional shape. However, it is not intended to be limited to these.

A solution containing the alkyl aluminum compound is applied to form a coating film, and then the formed coating film is calcined by setting the base material to a predetermined temperature and drying the organic solvent, or by heating to a predetermined temperature simultaneously with drying to obtain aluminum oxide form a thin film. The film thickness of the coating film formed by applying the alkyl aluminum compound-containing solution can be appropriately determined in consideration of the desired film of the aluminum oxide thin film. On the other hand, the base material may be heated to a predetermined temperature before application, or the solvent may be dried simultaneously with application by applying to a substrate heated to a predetermined temperature, or may be fired simultaneously with drying. The predetermined temperature is, for example, 300°C or less. Heating at a temperature of 300°C or lower can also be applied to non-heat resistant substrates such as plastics.

A predetermined temperature for drying the solvent may be selected from an arbitrary temperature, for example, from 20 to 250°C. The solvent may be dried over, for example, 0.5 to 60 minutes. However, it is not intended to be limited to these ranges.

The predetermined temperature for sintering to form the aluminum oxide can be selected arbitrarily, for example, from 50 to 600°C. However, considering the type of substrate, it is appropriate to set the temperature at which the substrate is not damaged. It is preferably 300°C or less from the viewpoint of being applicable to substrates having no heat resistance such as plastics. When the predetermined temperature for baking is the same as the predetermined temperature for drying the solvent, drying and baking of the solvent can be performed simultaneously. The solvent-dried precursor film can be fired over, for example, 0.5 to 300 minutes.

The film thickness of the aluminum oxide thin film obtained as described above may be, for example, in the range of 0.005 µm to 3 µm. However, it is not intended to be limited to this range, and the film thickness can be appropriately determined according to the intention to form an aluminum oxide thin film.

If necessary, the aluminum oxide thin film obtained as described above is subjected to an oxidizing gas atmosphere such as oxygen, a reducing gas atmosphere such as hydrogen, a water vapor atmosphere containing a large amount of moisture, or a plasma atmosphere such as argon, nitrogen, or oxygen. , the crystallinity and compactness of aluminum oxide can also be improved by heating to a predetermined temperature. Residual organic substances in the aluminum oxide thin film obtained by light irradiation such as ultraviolet rays or microwave treatment can be removed.

According to the manufacturing method of the present invention, a substrate with an aluminum oxide thin film having an aluminum oxide thin film having a vertical transmittance of 80% or more in visible light at 550 nm can be obtained on the substrate. The higher the vertical transmittance of the aluminum oxide thin film at 550 nm of visible light, the higher the transparency in the visible light region. For example, it is more preferably 90% or more, and more preferably 95% or more.

<Fifth aspect of the present invention>

[passive film forming agent]

The present invention relates to a passivation film forming agent. The passivation film means "a film formed on at least a part of the rear surface of the silicon substrate and suppressing recombination of the rear surface of the carrier in the silicon substrate". The silicon substrate on which the passivation film is formed is not particularly limited. However, a silicon substrate such as crystalline silicon may be used from the viewpoint of the high necessity of suppressing rear surface recombination of the carrier in the silicon substrate.

The passivation film forming agent of the present invention is an alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (however, the alkyl group of dialkyl aluminum and trialkyl aluminum has 1 to 6 carbon atoms, and may be the same or different. ), and a solution containing an alkyl aluminum compound containing an organic solvent having electron donating property and not containing an active hydrogen atom.

The solution containing an alkyl aluminum compound of the present invention chemically stabilizes an alkyl aluminum compound, which is dialkyl aluminum, trialkyl aluminum, or a mixture thereof, by containing an organic solvent having electron donating property and not containing an active hydrogen atom as an organic solvent. can make it The reason why an organic solvent having electron donating property and not containing an active hydrogen atom is preferable is not clear, but it is presumed that the reactivity to water is made appropriate by the coordination bond of the unshared electron pair of oxygen in the structure to aluminum.

The ratio of the alkyl aluminum compound in the solution of the present invention to the organic solvent having the electron donating property and not containing an active hydrogen atom is relative to the alkyl aluminum compound from the viewpoint of keeping the alkyl aluminum compound chemically stable. It is preferable to contain an organic compound having an electron donating property of 1 or more in molar ratio and not containing an active hydrogen atom. By containing an organic solvent that has an electron donating property of 1 or more in molar ratio to the alkyl aluminum compound and does not contain an active hydrogen atom, it is possible to suppress chemical changes such as spontaneous combustion of the solution and to make the reactivity to water appropriate. do.

The active hydrogen atom means a highly reactive hydrogen atom bonded to an atom of an element other than a carbon atom, such as a nitrogen atom, an oxygen atom, or a sulfur atom, among hydrogen atoms in the molecule of an organic compound.

Examples of the organic solvent having electron donating property and not containing active hydrogen atoms are the same as those of the organic solvent having electron donating property and not containing active hydrogen atoms in the fourth aspect of the present invention.

Alcoholic solvents such as ethanol, isopropanol, and butanol, and carboxylic acid solvents such as formic acid, acetic acid, and propionic acid all have active hydrogen atoms, so they are not organic solvents that have the electron donating ability and do not contain active hydrogen atoms. .

Since conjugated diketones such as acetyl acetone become enolate compounds and generate active hydrogen atoms, they are not organic solvents that have the electron donating ability and do not contain active hydrogen atoms.

In the case of the dialkyl aluminum and/or the trialkyl aluminum, the alkyl group of the dialkyl aluminum and the trialkyl aluminum has 1 to 6 carbon atoms, and the plurality of alkyl groups of one dialkyl aluminum or one trialkyl aluminum may be the same. Or they may be different.

The dialkylaluminum refers to a trivalent aluminum compound in which two ligands are alkyl groups and one is a non-alkyl group, and the trialkylaluminum refers to a trivalent aluminum compound in which all three ligands are alkyl groups.

Dialkyl aluminum and/or trialkyl aluminum may be, for example, an alkyl aluminum compound represented by the general formula (8) or (9), and the description in the fourth aspect of the present invention can be referred to. .

The dialkyl aluminum and/or the trialkyl aluminum is preferably triethyl aluminum or triisobutyl aluminum from the viewpoint of low cost per unit mass of aluminum.

The concentration of the alkyl aluminum compound in the alkyl aluminum-containing solution of the present invention may be, for example, 1% by mass or more and 20% by mass or less. In the case of the alkyl aluminum compound represented by the general formula (8), it is preferably 1 mass% or more and 10 mass% or less, and in the case of the alkyl aluminum compound represented by the general formula (9), it is preferably 1 mass% or more and 20 mass% or less. do. If it is less than 1% by mass, the productivity of the passivation film decreases, so it is preferably 1% by mass or more. The concentration of the alkyl aluminum compound in the alkyl aluminum-containing solution affects the risk of ignition or the like in the production of aluminum oxide, particularly by application in air. There exists an advantage that a passivation film can be manufactured safely.

The alkyl aluminum-containing solution of the present invention may further contain an organic solvent having no electron donating property and not containing an active hydrogen atom as an organic solvent other than the organic solvent having electron donating property and not containing active hydrogen atoms. . Polarity, viscosity, boiling point, economy, etc. can be adjusted by adding an organic solvent that does not have electron donating property and does not contain active hydrogen atoms. Examples of organic solvents that do not have electron donating property and do not contain active hydrogen atoms include aliphatic hydrocarbons such as n-hexane, octane, and n-decane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane, and ethylcyclohexane; Aromatic hydrocarbons, such as benzene, toluene, xylene, and cumene; Hydrocarbon solvents, such as mineral spirits, solvent naphtha, kerosene, and petroleum ether, etc. are mentioned. The addition amount of the organic solvent having no electron donating property and not containing an active hydrogen atom is not limited as long as it does not interfere with the effect of the organic solvent having electron donating property and not containing an active hydrogen atom. For example, It can be 100 parts by mass or less with respect to 100 parts by mass of the cyclic amide compound. However, the range that can be added varies depending on the type of the alkyl aluminum compound, the organic solvent that has electron donating property and does not contain active hydrogen atoms, and the type of organic solvent that does not have electron donating property and does not contain active hydrogen atoms. On the other hand, in the solution containing the alkyl aluminum compound, the alkyl aluminum compound in the solution containing the alkyl aluminum compound is chemically stabilized by containing an organic solvent having an electron donating property of 1 or more in terms of molar ratio with respect to the alkyl aluminum compound and not containing an active hydrogen atom. can make it Therefore, when an organic solvent that does not have electron donating property and does not contain an active hydrogen atom is used in combination, it is preferable to determine the combined amount in consideration of this point.

Mixing of the organic solvent having the above electron-donating property and not containing active hydrogen atoms, and, if necessary, the organic solvent having no electron-donating property and not containing active hydrogen atoms, with an alkyl aluminum compound is a reaction under an inert gas atmosphere. It can be carried out in a container, and each can be introduced according to all conventional methods. The alkyl aluminum compound can be introduced into the reaction vessel even as a mixture with an organic solvent that does not have electron donating property and does not contain an active hydrogen atom.

The order of introduction into the mixing vessel is the order of an alkyl aluminum compound, an organic solvent having electron donating property and not containing an active hydrogen atom, and, if necessary, an organic solvent having neither electron donating property nor containing an active hydrogen atom, or , an organic solvent having electron donating property and not containing an active hydrogen atom, and, if necessary, an organic solvent having neither electron donating property nor containing an active hydrogen atom, alkyl aluminum, which are introduced in this order, or all of them are introduced at the same time. It could be anything.

The introduction time into the mixing vessel can be appropriately set depending on the type and capacity of the raw materials to be mixed, but can be, for example, between 1 minute and 10 hours. As the temperature at the time of introduction, an arbitrary temperature between -15 and 150°C can be selected. However, considering safety such as elimination of the risk of ignition at the time of introduction, it is preferably in the range of -15 to 80 ° C.

At the time of introducing the raw material into the mixing vessel, the stirring step after the introduction may be any of a batch operation type, a semi-batch operation type, and a continuous operation type.

[Method of manufacturing a silicon substrate having a passivation film]

The method for manufacturing a silicon substrate having a passivation film of the present invention includes applying the alkyl aluminum compound-containing solution described as the passivation film forming agent of the present invention to at least a part of the back surface of a silicon substrate to form a coating film, and the formed coating film It is a method of obtaining a silicon substrate having a passivation film made of aluminum oxide, which includes forming a passivation film by drying the organic solvent, or in parallel with drying the organic solvent, by heating to form aluminum oxide.

The application to the silicon substrate is preferably performed by a method such as a spray coating method, an electrostatic spray coating method, an inkjet method, or a mist CVD method, and a spray coating method is more preferable because the apparatus is simpler.

Application to the substrate can be performed either under an inert atmosphere or an air atmosphere. In the case of an inert atmosphere, it can be carried out using a single device as shown in FIG. 5A.

Although the application to the substrate can be carried out either under pressure or under reduced pressure, from the viewpoint of economy, it is preferable to carry out the application under atmospheric pressure because the equipment is also simple.

The application to the substrate is carried out by applying the alkyl aluminum-containing solution to the silicon substrate as droplets having an average particle diameter of 1 to 100 μm. When droplets of an alkyl aluminum compound-containing solution with an average particle diameter of less than 1 μm are used, the efficiency of use of the material (adhesion efficiency to the substrate) decreases, and when droplets with an average particle diameter of more than 100 μm are used, the film formed by application is reduced. The average particle diameter of the alkyl aluminum-containing solution is limited to the above range because the properties (particularly, denseness) are lowered. When the alkyl aluminum-containing solution is applied to a substrate in the form of droplets having an average particle diameter of 3 to 30 μm, the material use efficiency (adhesion efficiency to the substrate) is high, and the properties of the film formed by application (particularly, compactness) are good. It is desirable from the point of view of For example, by passing an alkyl aluminum-containing solution through a spray nozzle for precision cloth, it can be made into droplets of 1 to 100 μm. The spray nozzle is preferably a two-fluid nozzle, and the droplets are preferably 3 to 30 μm. When it is 3 μm or more, the adhesion efficiency of droplets to the substrate is improved, and when it is 30 μm or less, film characteristics (transparency, in-plane uniformity, and compactness) are improved.

In the case of coating, it is preferable to carry out with the distance of a spray nozzle and a base material within 50 cm, and also more preferably within 20 cm. When the size of the droplet is greater than 50 cm, the solvent in the droplet dries until it reaches the substrate, and the size of the droplet decreases, reducing the adhesion efficiency of the droplet to the substrate.

It is preferable that the atmospheric temperature in the case of application|coating is 50 degreeC or less.

In the case of spray application in air, for example, an air atmosphere containing water at a relative humidity of 20 to 90% in terms of 25°C may be used. The relative humidity converted to 25°C is more preferably 30 to 70% from the viewpoint of smooth formation of the aluminum oxide thin film.

In the case of spray application in an inert atmosphere, by introducing water in the form of water vapor or the like from the water inlet 6 in the apparatus shown in FIG. It is carried out under an inert gas atmosphere.

Examples of the silicon substrate include amorphous silicon and crystalline silicon; Monocrystal silicon, polycrystal silicon, etc. are mentioned.

The shape of the silicon substrate may include a film, a plate, or a three-dimensional structure having a three-dimensional shape, for example, a spherical shape.

The silicon substrate is preferably a crystalline silicon substrate from the viewpoint of effective passivation effect.

A solution containing the alkyl aluminum compound is applied to form a coating film, and then the formed coating film is calcined by setting the base material to a predetermined temperature and drying the organic solvent, or by heating to a predetermined temperature simultaneously with drying to obtain aluminum oxide form a thin film. The film thickness of the coating film formed by applying the alkyl aluminum compound-containing solution can be appropriately determined in consideration of characteristics required as a passivation film. On the other hand, the base material may be heated to a predetermined temperature before application, or the solvent may be dried simultaneously with application by applying to a substrate heated to a predetermined temperature, or may be fired simultaneously with drying.

A predetermined temperature for drying the solvent may be selected from an arbitrary temperature, for example, from 20 to 250°C. The solvent may be dried over, for example, 0.5 to 60 minutes. However, it is not intended to be limited to these ranges.

The predetermined temperature for sintering to form the aluminum oxide can be selected arbitrarily, for example, from 300 to 600°C. However, considering the type of substrate, it is appropriate to set the temperature at which the substrate is not damaged. When the predetermined temperature for baking is the same as the predetermined temperature for drying the solvent, drying and baking of the solvent can be performed simultaneously. The solvent-dried precursor film can be fired over, for example, 0.5 to 300 minutes.

In particular, it is estimated that more negative fixed charges can be generated by setting the firing temperature to 350 to 500°C.

The film thickness of the passivation film made of aluminum oxide obtained as described above may be, for example, in the range of 0.005 μm to 3 μm, and preferably in the range of 0.01 μm to 0.3 μm. When it is set to 0.01 μm or more, the continuity of the film is improved, and the possibility of occurrence of areas where the film is not adhered can be lowered. There is an advantage that the possibility is low.

If necessary, the aluminum oxide thin film obtained as described above is subjected to an oxidizing gas atmosphere such as oxygen, a reducing gas atmosphere such as hydrogen, a water vapor atmosphere containing a large amount of moisture, or a plasma atmosphere such as argon, nitrogen, or oxygen. , the crystallinity and compactness of aluminum oxide can also be improved by heating to a predetermined temperature. Residual organic substances in the aluminum oxide thin film obtained by light irradiation such as ultraviolet rays or microwave treatment can be removed.

According to the manufacturing method of the present invention, the effective lifetime is, for example, in the range of 150 to 2000 μs, and the recombination rate is, for example, 7 to 100 cm/s when using a silicon substrate having a thickness of 300 μm. A passivation film in the range of can be formed on the silicon substrate. The effective lifetime of the aluminum oxide film formed by heating and firing can be further treated in a forming gas atmosphere, and the recombination rate can be increased. Examples of the forming gas include non-oxidizing gases (hydrogen-containing gas, nitrogen-containing gas, etc.).

[solar cell element]

The present invention includes a solar cell device using a silicon substrate having the passivation film of the present invention.

5B shows an example of an embodiment of the solar cell device of the present invention. The p-type solar cell element 100 is composed of a p-type silicon semiconductor substrate 11 having a thickness of 180 to 300 μm. On the surface of the light-receiving surface side of (11), an n ⁺ layer 12, which is an n-type impurity layer with a thickness of 0.3 to 1.0 μm, an antireflection and passivation thin film 13 made of a silicon nitride thin film thereon, and a silver The grid electrodes 15 are each formed by a plasma CVD method using SiH ₃ and NH ₃ or a screen printing method using a paste composition containing silver powder.

On the back surface of the silicon semiconductor substrate 11 opposite to the light-receiving surface side, a passive thin film 14 made of an aluminum oxide thin film according to the present invention is formed, and an aluminum electrode 16 conforming to a predetermined pattern shape so as to penetrate (14) is formed. is formed

The aluminum electrode 16 is usually formed by applying a paste composition containing aluminum powder by screen printing or the like, drying it, and then baking it at a temperature higher than 660° C., which is the melting point of aluminum, for a short time of 1 to 10 seconds. During this firing (fire through), aluminum diffuses into the silicon semiconductor substrate 11, so that an Al-Si alloy layer 17 is formed between the aluminum electrode 16 and the silicon semiconductor substrate 11. is formed, and at the same time, a P ⁺ layer (Back Surface Field (BSF) layer) 18 is formed as an impurity layer by diffusion of aluminum atoms.

[ Example ]

Hereinafter, the present invention will be described in more detail based on examples. However, the examples are examples of the present invention, and the present invention is not intended to be limited to the examples.

<First aspect of the present invention>

The preparation of the alkyl aluminum compound-containing solution and the alkyl aluminum partial hydrolyzate-containing solution of the present invention was performed under a nitrogen gas atmosphere, and all solvents were dehydrated and degassed before use.

<Number of moles of trialkyl aluminum>

The number of moles of trialkyl aluminum was calculated from the following formula.

[Number of moles of trialkyl aluminum]

= [mass of introduced trialkyl aluminum (g)]/[molecular weight of trialkyl aluminum (114.16 in the case of triethyl aluminum)]

<Measurement of physical properties>

After dissolving the solvent of the alkyl aluminum compound-containing solution of the present invention, the alkyl aluminum partial hydrolyzate-containing solution, and the alkyl aluminum partial hydrolyzate-containing solution dried by an evaporator in C ₆ D ₆ , an NMR device (manufactured by JEOL RESONANCE “ JNM-ECA500”) was used for 1H-NMR measurement.

The solvent of the alkyl aluminum partial hydrolyzate-containing solution of the present invention was dried by an evaporator, and IR measurement was performed by the transmission method with an FT-IR spectrometer (“FT/IR-4100” manufactured by Nippon Bunko Co., Ltd.). conducted.

The stability of the alkyl aluminum compound-containing solution and the alkyl aluminum partial hydrolyzate-containing solution of the present invention to air is described in Section 3 "Hazardous Substances Identification Test Manual" (Fire Agency Hazardous Substances Regulation and Supervision, New Japan Law Publishing Co., Ltd., 1989). 3rd class test method”, 2 “spontaneous ignition test”. Those that ignite spontaneously even on the magnetic cup were ranked 1, those that did not ignite spontaneously on the magnetic cup but burned the filter paper were ranked 2, and those that did not spontaneously ignite and did not burn the filter paper were classified as "no danger".

The aluminum oxide thin film produced by the production method of the present invention is ATR (Attenuated Total Reflection: Total Reflection) method using a ZnSe prism in an FT-IR spectrometer (“FT/IR-4100” manufactured by Nippon Bunko Co., Ltd.) without ATR correction Relative IR measurements were performed.

Originally, in the case of using a ZnSe prism, it was difficult to measure a thin film having a refractive index exceeding 1.7, and considering that the refractive index of general aluminum oxide is 1.77, measurement was assumed to be difficult. However, surprisingly, measurements were possible. It was estimated that the refractive index of the aluminum oxide thin film according to the present invention was 1.7 or less.

In the aluminum oxide thin film produced by the production method of the present invention, a portion of the film was cut with a knife, and the film thickness was measured using a stylus-type surface shape measuring device (DektakXT-S, manufactured by Vulcanano Co., Ltd.).

[Example 1-1]

To 20.0 g of N-methyl-2-pyrrolidone (hereinafter referred to as NMP), 5.31 g of triethylaluminum (manufactured by Tosoh FineChem) was added at 25°C and sufficiently stirred to obtain a 21% by mass triethylaluminum NMP solution. When the NMR spectrum was remeasured after 24 hours, the same spectrum as the first obtained spectrum was obtained.

When the 21 mass % triethylaluminum NMP solution obtained in this way was tested for pyrophoricity, it was classified as "no danger".

[Example 1-2]

A 21% by mass trimethylaluminum NMP solution was obtained by adding 1.32 g of trimethylaluminum (manufactured by Tosoh FineChem) to 5.00g of NMP at 25°C and stirring sufficiently. When the 21 mass % trimethylaluminum NMP solution obtained in this way was tested for pyrophoricity, it was classified as "no danger".

[Example 1-3]

A 41% by mass triisobutylaluminum NMP solution was obtained by adding 3.48 g of triisobutylaluminum (manufactured by Tosoh FineChem) to 5.00g of NMP at 25°C and stirring sufficiently. When the 41 mass % triisobutylaluminum NMP solution obtained in this way was tested for pyrophoricity, it was classified as "no danger".

The results of the spontaneous ignition test so far are summarized in Table 1-1.

[Table 1-1]

[Example 1-4]

To 8.01 g of NMP, 0.90 g of mixed xylene and 2.10 g of triethylaluminum were added at 25°C, and sufficiently stirred to obtain a 19% by mass triethylaluminum NMP xylene mixed solution. When the 19% by mass triethylaluminum NMP-xylene mixed solution obtained in this way was subjected to a pyrophoric test, it was classified as "no danger".

[Example 1-5]

To 8.01 g of NMP, 0.90 g of mixed xylene and 2.11 g of trimethylaluminum (manufactured by Tosoh FineChem) were added at 25°C, and sufficiently stirred to obtain a 19% by mass trimethylaluminum NMP xylene mixed solution. When the 19% by mass trimethylaluminum NMP-xylene mixed solution obtained in this way was subjected to a pyrophoric test, it was classified as "no danger".

[Example 1-6]

To 20.0 g of NMP was added 8.59 g of triethyl aluminum (manufactured by Tosoh FineChem) at 25°C, followed by sufficient stirring. Thereafter, 6.77 g ([water]/[triethylaluminum] = 1.0) of a 20% by mass water NMP solution was added dropwise over 50 minutes at 25°C. By continuing stirring at 25 degreeC for 5 hours, the aging reaction was performed and the triethyl aluminum hydrolysis composition NMP solution was obtained. As a result of NMR measurement, a spectrum as shown in FIG. 1A was obtained, and disappearance of a peak corresponding to triethylaluminum was confirmed.

When the obtained triethylaluminum hydrolysis composition NMP solution was solvent-dried using an evaporator at 70° C. for 90 minutes and subjected to IR measurement by the transmission method, a spectrum as shown in FIG. 1B was obtained. A broad Al-O-Al vibration peak was confirmed at around 400 to 1500 cm ^-1 , confirming the formation of an Al-O-Al bond by hydrolysis.

[Example 1-7]

To 18.0 g of NMP, 2.00 g of mixed xylene and 8.59 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) were added at 25°C, followed by sufficient stirring. Thereafter, 6.77 g ([water]/[triethylaluminum] = 1.0) of a 20% by mass water NMP solution was added dropwise over 50 minutes at 25°C. A aging reaction was performed by continuing stirring at 25°C for 5 hours, and a triethylaluminum hydrolysis composition NMP solution was obtained. As a result of NMR measurement, disappearance of the peak corresponding to triethylaluminum was confirmed as in Example 1-6.

[Example 1-8]

50 μl of the NMP solution of the triethylaluminum hydrolysis composition obtained in Example 1-6 was dropped on a 18 mm square glass substrate (EagleXG, manufactured by Corning) under an air atmosphere, and then spun at 2000 rpm for 20 seconds by a spin coater. applied. After drying at 25°C for 1 minute, a thin film was formed by heating at 90°C for 5 minutes.

A transparent thin film as shown in FIG. 1c was obtained, and as a result of IR measurement by the ATR method, a spectrum as shown in FIG. 1d was obtained. A broad Al-O-Al vibration peak around 550 to 1500 cm ^-1 and a broad Al-OH vibration peak around 2500 to 4000 cm ^-1 were confirmed, and Al-O-Al and Al-OH bonds formation was confirmed. Thus, formation of an aluminum oxide thin film was confirmed. Since there was no vibration peak of organic matter around 3000 cm ^-1 , it was confirmed that there was no remaining organic matter. The IR spectrum of the glass substrate itself by the ATR method is FIG. 1e and is clearly different from FIG. 1d. The film thickness was 638 nm.

<Second aspect of the present invention>

Preparation of solutions containing all of the organoaluminum compounds and film formation using them were conducted under a nitrogen gas atmosphere, and all solvents were dehydrated and degassed before use.

<Number of moles of trialkyl aluminum>

It is the same as the first aspect of the present invention.

Water during film formation on the aluminum oxide film was supplied to the film formation atmosphere in a state where water was saturated in nitrogen by bubbling nitrogen into heated water as needed.

Formation of aluminum oxide and its film on the substrate in each film formation in Examples and Comparative Examples is ATR-IR (infrared spectroscopy by an attenuated total reflection (ATR) method), EPMA (Electron Probe Microscope) Analyzer: electron beam microanalyzer) and XRD (X-ray diffraction: X-ray diffraction) analysis was confirmed.

- The transmittance of visible light and the like was measured using a spectrophotometer.

- The film thickness of the aluminum oxide film was measured by a stylus-type surface profilometer or by SEM measurement of a thin film section.

- The adhesion of the formed aluminum oxide film to the substrate is JIS K 5600-5-6 "General test methods for paints - Part 5: Mechanical properties of paint films - Section 6: Adhesion (crosscut method)" or Scotch tape (registration Trademark) (manufactured by 3M Co., Ltd.), was confirmed by a peeling test by tape sticking and peeling to an aluminum oxide film formed by coating it on a base material using an adhesive tape such as cellophane tape.

- Regarding the reactivity of the chemical solution, the chemical solution was dropped onto the filter paper in a windless atmosphere with constant temperature (20 ° C) and humidity (50%), and the reactivity on the filter paper was visually confirmed.

- The moisture value in the nitrogen atmosphere was determined by dew point measurement and was converted into volume%.

- In the nitrogen atmosphere during coating and solvent drying and heating at the time of film formation, the moisture content in the nitrogen gas is in the range of 100 ppm (dew point temperature -42 ° C) to 375 ppm (dew point temperature -30 ° C) unless there is a special rejection. controlled. Further, by adjusting the setting, it is also possible to adjust within the range of 5 ppm (dew point temperature -66°C) to 375 ppm (dew point temperature -30°C).

[Example 2-1]

To 73.2 g of tetrahydrofuran (THF), 11.35 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 36.6 g of a THF solution containing 1.08 g of water was stirred so that the molar ratio of water to TEAL (water/TEAL) was 0.6 while removing heat generated by the reaction so that the temperature was around 20°C. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition A) was obtained. In addition, ¹ H-NMR (THF-d ₈ , ppm) was measured for a residue containing as a main component a product obtained by partially hydrolyzing triethyl aluminum after removing a solvent or the like from a part of Composition A by vacuum drying, The spectrum in Fig. 2b was obtained.

This composition A was applied on the surface of a 18 mm square (thickness: 0.7 mm) glass substrate (EagleXG (registered trademark), manufactured by Corning) by a spin coating method. In a nitrogen atmosphere, at room temperature, 50 μl of the solution was dropped onto the glass substrate, the substrate was rotated at a rotation speed of 1000 rpm for 20 seconds, the solution was applied to the entire glass substrate, and after drying at room temperature, the substrate was heated at a predetermined temperature. By heating for 2 minutes, the solvent was dried and a film was formed at the same time.

The film-attached substrate was taken out into the atmosphere, and the obtained film was analyzed by ATR-IR. The film obtained by heating at any temperature was found to be free from the solvent contained in Composition A and the partial hydrolyzate of triethylaluminum. It was confirmed that no peak derived from an organic substance such as an ethyl group was observed and that an aluminum oxide film was formed. Fig. 2c shows the film obtained by heating at 130 °C, and Fig. 2d shows the ATR-IR analysis results of only the glass substrate. All of the obtained films had high transmittance and were transparent, and the vertical transmittance at 550 nm of the films obtained by heating at each temperature obtained values shown in Table 2-1.

[Table 2-1]

[Example 2-2]

In Example 2-1, the operation of the coating film was repeated three times to obtain a film similarly at 300°C. The vertical transmittance at 550 nm of the aluminum oxide film obtained by heating at 300°C was 94%.

[Example 2-3]

To 74.18 g of tetrahydrofuran (THF), 27.94 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 38.04 g of a THF solution containing 4.41 g of water was stirred so that the molar ratio of water to TEAL (water/TEAL) was 1.0 while removing heat generated by the reaction so that the temperature was around 20°C. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition B) was obtained. In addition, ¹ H-NMR (THF-d ₈ , ppm) was measured for a residue containing as a main component a product obtained by partially hydrolyzing triethyl aluminum after removing a solvent or the like from a part of Composition B by vacuum drying, The spectrum in Fig. 2e was obtained.

Using this composition B, a coating film was formed on a glass substrate in the same manner as in Example 2-1. Heating after application and drying of the solvent was performed at each temperature of 50, 100, 130, 200, 250, 300, 350, and 400°C for 2 minutes each. The substrate with the film obtained at each temperature was taken out into the atmosphere, and the obtained film was analyzed by ATR-IR. A peak derived from organic substances such as the solvent contained in composition B and the ethyl group contained in the partial hydrolyzate of triethyl aluminum was found. What was not confirmed and formation of an aluminum oxide film were confirmed. All of the obtained films were transparent with high transmittance, and the vertical transmittance at 550 nm of the films obtained by heating at each temperature obtained values shown in Table 2-2.

[Table 2-2]

[Comparative Example 2-1]

In Example 2-1, the vertical transmittance at 550 nm of the aluminum oxide film obtained by performing the heating temperature after coating at 450°C or 500°C obtained values of 79 and 78%, respectively. It was found that the heating temperature of the coated film is preferably 400°C or less.

[Example 2-4]

In Example 2-3, the coating film operation was repeated 3 times to obtain a film similarly at 350°C. The vertical transmittance at 550 nm of the aluminum oxide film obtained by heating at 350°C obtained a value of 84%.

[Comparative Example 2-2]

To 150 g of tetrahydrofuran (THF), 15.0 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. A TEAL/THF solution (composition 1) obtained by sufficiently stirring was obtained.

As a substrate for forming an aluminum oxide film, a polypropylene (PP) film (30 mm square (thickness: 0.2 mm)) was used, a TEAL/THF solution (composition 1) was used, the amount of composition 1 was 200 µl, and the number of revolutions was applied at 500 rpm and the same coating operation as in Example 2-1 was performed. After drying, the film was heated at 130° C. for 2 minutes, and an aluminum oxide film was formed by spin coating. The same analysis of the film formed on the substrate was performed, but almost no oxide adhered to the substrate, and the formation of an aluminum oxide film on a polypropylene (PP) film at a low temperature of 130 ° C. was confirmed by the film formation method using this solution. couldn't Further, the same operation was performed by changing the base material from a polypropylene (PP) film to a glass substrate (EagleXG (registered trademark), manufactured by Corning) of 18 mm square (thickness: 0.7 mm), but the formation of an aluminum oxide film was not confirmed.

The film formation method was changed to the dip coating method, and a polypropylene (PP) film (15 mm square (thickness: 30 μm)) was immersed in Composition X for 1 second under a nitrogen atmosphere, the film was pulled up, and the liquid soaked in the film was dropped. Dropped. After drying the solvent at room temperature, it was further left at room temperature for 10 minutes or heated at 50°C for 10 minutes to form a film on a polypropylene (PP) film. Similar analysis was performed on the film formed on the substrate, but almost no oxide adhered to the substrate, and the formation of an aluminum oxide film on a polypropylene (PP) film at a low temperature of 50 ° C. by the film formation method using this solution Couldn't confirm.

[Comparative Example 2-3]

In Example 2-3, except that 4.41 g of water was not added, a TEAL/THF solution (composition 2) in which TEAL was not partially hydrolyzed was obtained in the same manner as in Example 2-3. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching was observed on the filter paper, and it was found that it was difficult to handle a TEAL/THF solution that had not undergone partial hydrolysis as a solution with a high Al concentration.

[Comparative Example 2-4]

In Example 2-2, 32.9 g of aluminum triisopropoxide and 4.41 g of water were used instead of 70.0 g of tetrahydrofuran (THF) and 27.94 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.). Example, except that 11.6 g of THF solution containing 2.9 g of water was added dropwise instead of 38.04 g of THF solution containing water so that the molar ratio of water to Al contained in aluminum triisopropoxide (water/Al) became 1. An attempt was made to obtain a solution in which aluminum triisopropoxide was partially hydrolyzed using the same method as in 2-2, but a large amount of white insoluble matter was precipitated, and it was found that it contained sufficient Al concentration as a uniform coating solution. couldn't get

[Comparative Example 2-5]

In Example 2-2, 70.0 g of toluene instead of 74.18 g of tetrahydrofuran (THF), 32.3 g of aluminum triisopropoxide and 4.41 g of water instead of 27.94 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) The same method as in Example 2-2 was used except that 11.4 g of a THF solution containing 2.84 g of water was added dropwise instead of 38.04 g of a THF solution containing Therefore, an attempt was made to obtain a solution in which aluminum triisopropoxide was partially hydrolyzed. In the obtained reaction product, a large amount of white insoluble matter precipitated, and it was not possible to obtain one containing a sufficient Al concentration as a uniform coating solution.

[Example 2-5]

To 73.21 g of tetrahydrofuran (THF), 11.35 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 36.60 g of a THF solution containing 2.09 g of water was added while removing heat generated by the reaction in a temperature range of 20 to 26° C., and the molar ratio of water to TEAL (water/TEAL) was It was added dropwise while stirring so as to become 1.17. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition C) was obtained. In addition, ¹ H-NMR (THF-d ₈ , ppm) measurement was performed on a residue containing as a main component a product obtained by partially hydrolyzing triethyl aluminum obtained by removing a solvent or the like from a part of Composition C by vacuum drying. , obtained the spectrum in Fig. 2f.

Using this composition C, a coating film was applied to a glass substrate in the same manner as in Example 2-1, the substrate with the film obtained at each temperature was taken out into the air, and the obtained film was analyzed by ATR-IR. It was confirmed that peaks derived from organic substances such as the solvent contained in C or the ethyl group contained in the partial hydrolyzate of triethyl aluminum were not confirmed, and the formation of an aluminum oxide film was confirmed. All of the obtained films had high transmittance and were transparent, and the vertical transmittance at 550 nm of the films obtained by heating at each temperature obtained values shown in Table 2-3.

[Table 2-3]

[Example 2-6]

In Example 2-5, the operation of the coated film was repeated three times to obtain a film at 300°C similarly. The vertical transmittance at 550 nm of the aluminum oxide film obtained by heating at 300°C was 98%.

[Example 2-7]

To 166.7 g of toluene, 23.5 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 19.54 g of a THF solution containing 3.92 g of water was stirred at 16 to 27° C. while controlling the exotherm by heat removal so that the molar ratio of water to TEAL (water/TEAL) was 1.06. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition D) was obtained.

Using this composition D, it was applied to a polypropylene (PP) board (50 mm square (3 mm thick)) by a dip coating method. A polypropylene board was immersed in the composition D for 1 second under a nitrogen atmosphere, and after the film was pulled up, the liquid soaked in the film was cut off and dropped. After drying the solvent at room temperature, it was heated at 50 or 100° C. for 10 minutes to form a film on a polypropylene (PP) plate.

The substrate with the film obtained at each temperature was taken out into the atmosphere, and the obtained film was analyzed by ATR-IR. A peak derived from organic substances such as the solvent contained in the composition D and the ethyl group contained in the partial hydrolyzate of triethylaluminum was found. What was not confirmed and formation of an aluminum oxide film were confirmed. All of the obtained films were transparent.

Adhesion of the obtained film was subjected to an adhesion test based on JIS K 5600-5-6 "General test methods for paints - Part 5: Mechanical properties of coating films - Part 6: Adhesion (crosscut method)". When the scotch tape (registered trademark) 2364 (manufactured by 3M) adhered to the film was removed and visually confirmed, “Classification 1: There was small peeling of the coating film at the intersection of the cuts. The influence of the cross-cut portion was clearly not less than 5%.”, confirming that the adhesion of the film to the substrate was good. In addition, when the state of the film was confirmed by ATR-IR and SEM measurements, peeling of a strong film was not confirmed, and it was confirmed that the film formed by the present composition had high adhesion.

[Example 2-8]

In Example 2-7, a film was formed on the acrylic plate in the same manner as in Example 2-3, using an acrylic plate instead of the polypropylene (PP) film plate and setting the heating temperature to 50°C. The obtained film was analyzed by ATR-IR, and it was confirmed that no peaks derived from organic substances such as the solvent contained in composition D or the ethyl group contained in the partial hydrolyzate of triethylaluminum were observed and that an aluminum oxide film was formed. The adhesion of the obtained film was confirmed by the same test as in Example 2-7, and it was "Class 1" in the test by the cross-cut method, and peeling of the strong film was not confirmed, and the adhesion of the film formed by the present composition was high. Confirmed.

[Example 2-9]

In Example 2-1, instead of 36.6 g of a THF solution containing 108.45 g of tetrahydrofuran (THF), 15.13 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) and 1.08 g of water, The reaction was carried out using the same method as in Example 2-1, except that 48.8 g of a THF solution containing 0.95 g of water was added dropwise so that the molar ratio of water to TEAL (water/TEAL) was 0.4. got Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition E) was obtained.

[Example 2-10]

In Example 2-9, the same method as in Example 2-9 was used, except that 1.44 g of water was added dropwise instead of 0.95 g of water so that the molar ratio of water to TEAL (water/TEAL) was 0.6. A colorless and transparent solution was obtained. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition F) was obtained.

[Example 2-11]

In Example 2-9, the same method as in Example 2-9 was used except that 1.91 g of water was added dropwise instead of 0.95 g of water so that the molar ratio of water to TEAL (water/TEAL) was 0.8. A colorless and transparent solution was obtained. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition G) was obtained.

[Example 2-12]

In Example 2-9, the same method as in Example 2-9 was used except that 2.79 g of water was added dropwise instead of 0.95 g of water so that the molar ratio of water to TEAL (water/TEAL) was 1.17. A colorless and transparent solution was obtained. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition H) was obtained.

[Example 2-13]

In Example 2-9, the same method as in Example 2-9 was used except that 2.98 g of water was added dropwise instead of 0.95 g of water so that the molar ratio of water to TEAL (water/TEAL) was 1.25. A colorless and transparent solution was obtained. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition I) was obtained.

Tables 2-4 show the water/TEAL molar ratio, the appearance of reaction products, the state of gel formation, and the reactivity of the compositions for each composition prepared in Examples 2-9, 10, 11, 12, and 13, respectively.

[Table 2-4]

[Example 2-14]

To 79.92 g of tetrahydrofuran (THF), 11.35 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 36.60 g of a THF solution containing 1.79 g of water was stirred so that the molar ratio of water to TEAL (water/TEAL) was 1.0 while removing heat generated by the reaction so that the temperature was around 20°C. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition J) was obtained.

[Example 2-15]

To 67.5 g of tetrahydrofuran (THF), 24.07 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, isopropanol 12. 67 g was added dropwise while stirring. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was cooled to 18°C, and 30.05 g of a THF solution containing 3.8 g of water was stirred so that the molar ratio of water to TEAL (water/TEAL) was 1.0 while removing heat from the reaction to reach around 20°C. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. In addition, a part of the obtained solution was analyzed by ¹ H-NMR (Fig. 2g) and ²⁷ Al-NMR (Fig. 2h) (both benzene-d ₆ , ppm) for the residue after removing the solvent and the like by vacuum drying. , it was confirmed that an isopropoxyl group was present in the structure of the product.

In this way, a composition for producing an aluminum oxide film (composition K) containing a product obtained by partially hydrolyzing triethyl aluminum having an isopropoxy group in the structure was obtained.

Using this composition K, a coating film was formed on a glass substrate in the same manner as in Example 2-1. Heating after application and drying of the solvent was performed at each temperature of 250, 300, 350, and 400°C for 2 minutes. The substrate with the film obtained at each temperature was taken out into the atmosphere, and the film obtained was analyzed by ATR-IR, and the solvent contained in Composition B and the ethyl contained in the partial hydrolyzate of triethylaluminum having an isopropoxy group in the structure were determined. It was confirmed that peaks derived from organic substances, such as groups and isopropoxy groups, were not confirmed and that an aluminum oxide film was formed. All of the obtained films were transparent with high transmittance, and the vertical transmittance at 550 nm of the films obtained by heating at each temperature obtained values shown in Table 2-5.

[Table 2-5]

[Example 2-16]

5 g of the composition for producing an aluminum oxide film (composition K) containing a product obtained by partially hydrolyzing triethyl aluminum having an isopropoxy group was aliquoted, 5 g of isopropanol was added, and thoroughly mixed, but the solution remained as a homogeneous solution. The composition for preparing an aluminum oxide film (composition K) containing a product obtained by partially hydrolyzing triethylaluminum having an isopropoxy group in its structure (composition K) may use an alcohol such as isopropanol as a solvent.

[Example 2-17]

2.14 g of a composition for preparing an aluminum oxide film (composition K) containing a product obtained by partially hydrolyzing triethyl aluminum having an isopropoxy group in the structure obtained in Example 2-15 was aliquoted, and THF was removed from this, and 0.943 The solution was concentrated to g. The concentrate obtained was a clear gel-like solid. When 0.25 g of toluene was added to the concentrate and mixed, the solid matter was dissolved to form a homogeneous solution. In this way, the product obtained by partially hydrolyzing triethyl aluminum having an isopropoxy group included in the composition for producing an aluminum oxide film (composition K) does not contain inorganic substances such as aluminum oxide or hydroxide insoluble in organic solvents.

[Example 2-18]

5 g of the composition for producing an aluminum oxide film (composition B) containing a product obtained by partially hydrolyzing triethylaluminum obtained in Example 2-2 was aliquoted, and 5 g of isopropanol was added thereto at room temperature (20°C) while stirring. , the reaction was performed until ethane produced in the reaction ceased to be generated. The obtained solution was uniform, and ¹ H-NMR (benzene-d ₆ , ppm) was analyzed after removing the solvent and the like from a part of the obtained solution by vacuum drying, and it was confirmed that an isopropoxy group exists in the structure of the product. Confirmed.

In this way, it is possible to obtain a composition for producing an aluminum oxide film (composition L), which is a product obtained by the reaction of a product obtained by partially hydrolyzing triethyl aluminum with isopropanol and has an isopropoxy group in the structure, and this product is isopropanol Even if they coexist, they remain a homogeneous solution. In this way, the solution for preparing an aluminum oxide film having an isopropoxy group in the structure obtained through the partial hydrolysis of triethylaluminum (composition L) may use an alcohol such as isopropanol as a solvent.

[Example 2-19]

To 74.1 g of 1,2-diethoxyethane, 27.91 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 38 g of a THF solution containing 4.41 g of water was added while stirring so that the molar ratio of water to TEAL (water/TEAL) was 1.0 while removing heat generated by the reaction so that the temperature was around 20°C. Dropped. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after reaction was a pale yellow transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition M) was obtained.

[Example 2-20]

To 74.1 g of tetrahydrofuran (THF), 27.91 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 38 g of a THF solution containing 4.41 g of water was stirred at 20 to 27° C. while removing heat from the reaction so that the molar ratio of water to TEAL (water/TEAL) was 1.0. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, the reaction mixture was cooled to 18°C, and 14.69 g of isopropanol was added dropwise while stirring at 18 to 20°C while removing heat from the reaction. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film (composition N) containing a product obtained by partially hydrolyzing triethyl aluminum having an isopropoxy group in the structure was obtained. In addition, ¹ H-NMR (benzene-d ₆ , ppm) measurement was performed on the residue after solvent and the like were removed from part of the composition N by vacuum drying, and the spectrum shown in FIG. 2I was obtained. This composition N gives almost the same peak pattern as composition K, which is a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethyl aluminum having an isopropoxy group in its structure, and similarly to composition K, the composition of the aluminum oxide film It can be used for coating formation.

[Example 2-21]

To 10.0 g of toluene, 1.31 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 1.03 g of a THF solution containing 0.21 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) became 1.0. Then, it was made to react at 25 degreeC for 18 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. Part of the obtained solution was vacuum-dried to remove the solvent and the like, and for the residue mainly composed of a product obtained by partially hydrolyzing triethylaluminum, ¹ H-NMR and ²⁷ Al-NMR (both benzene-d ₆ , ppm ), and the respective spectra of FIG. 2j ( ¹ H-NMR) and FIG. 2k ( ²⁷ Al-NMR) were obtained. Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition O) was obtained.

Using this composition O, it was applied to a polypropylene (PP) film (15 mm square (thickness: 30 μm)) by a dip coating method. A polypropylene (PP) film (15 mm square (30 μm thick)) was immersed in Composition O for 1 second at room temperature under a nitrogen atmosphere, and after the film was pulled up, the liquid soaked in the film was cut off and dropped. After drying the solvent at room temperature, it was further left at room temperature for 10 minutes or heated at 50°C for 10 minutes to form a film on a polypropylene (PP) film.

The substrate with the film obtained at each temperature was taken out into the atmosphere, and the obtained film was analyzed by ATR-IR, and peaks derived from organic substances such as the solvent contained in the composition O and the ethyl group contained in the partial hydrolyzate of triethylaluminum were found. What was not confirmed and formation of an aluminum oxide film were confirmed. All of the obtained films were transparent.

The adhesion of the obtained film was confirmed by a peel test using a cellophane tape having a width of 12 mm. A cellophane tape was pressed firmly onto the film-formed surface of the polypropylene (PP) film on which the aluminum oxide film was formed, and peeled off at an angle of 45°. When it was confirmed by visual observation, ATR-IR, and SEM measurement after peeling off, peeling of the strong film was not confirmed, and it was confirmed that the film formed by the present composition had high adhesion.

[Example 2-22]

In Example 2-21, a film was formed on a polypropylene (PP) film in the same manner as in Example 2-22, except that heating at 50° C. for 10 minutes was performed in air in a nitrogen atmosphere.

The obtained film was analyzed by ATR-IR, and it was confirmed that no peaks derived from organic substances such as ethyl groups contained in the solvent contained in Composition O or the partial hydrolyzate of triethyl aluminum were observed, and the formation of an aluminum oxide film was confirmed. The resulting film was transparent.

The adhesion of the obtained film was confirmed by the same test as in Example 2-21, and peeling of the strong film was not confirmed, and it was confirmed that the film formed from the present composition had high adhesion.

[Example 2-23]

In Example 2-21, instead of the polypropylene (PP) film (15 mm square (30 μm thick), a porous polypropylene (PP) film (for secondary battery separator: 15 mm square (20 μm thick)) was used. was used, and a film was formed on a porous polypropylene (PP) film in the same manner as in Examples 2-21 and 2-22. It was confirmed that peaks derived from organic substances such as ethyl groups contained in the partial hydrolyzate were not confirmed and that an aluminum oxide film was formed.FIG. 2L shows a film obtained by heating at 50° C. The ATR-IR analysis results of only the porous polypropylene (PP) film obtained by heating at 50 ° C. and the porous polypropylene (PP) film without film formation are shown in Fig. 2n. When the surface was analyzed by EPMA, Al and O (oxygen ) was confirmed.

The adhesion of the obtained film was confirmed by the same test as in Example 2-21, and peeling of the strong film was not confirmed, and it was confirmed that the film formed from the present composition had high adhesion.

[Example 2-24]

In Example 2-21, a polypropylene (PP) film (18 mm square (0.7 mm thick) glass substrate (EagleXG (registered trademark), manufactured by Corning) was used instead of 15 mm square (thickness 30 μm)) , A film was formed on a glass substrate in the same manner as in Examples 2-21 and 2-22 The heating temperature after application was room temperature (without heating), 50, 100, 200, 300, 400, and 500°C. did

The obtained film was analyzed by ATR-IR, and it was confirmed that no peaks derived from organic substances such as ethyl groups contained in the solvent contained in Composition O or the partial hydrolyzate of triethyl aluminum were observed, and the formation of an aluminum oxide film was confirmed. Further, when the film heated at 50°C in a nitrogen atmosphere was taken out into the air and the film thickness was measured by SEM analysis, Fig. 2O was obtained, and the film thickness calculated therefrom was 470 nm. In addition, SEM analysis was performed on the surface of the film, and the result shown in FIG. 2P was obtained.

The adhesion of the obtained film was confirmed by the same test as in Example 2-21, and peeling of the strong film was not confirmed, and it was confirmed that the film formed from the present composition had high adhesion.

[Example 2-25]

In Examples 2-21, instead of the polypropylene (PP) film (15 mm square (30 μm thick), polyethylene terephthalate (PET) film (15 mm square (25 μm thick) and 30 mm square (188 μm thick)) ) was used to form a film on a PET film in the same manner as in Examples 2-21 and 2-22 Heating after coating and drying was carried out at room temperature (no heating), at each temperature of 50, 100, and 130 ° C. for 2 minutes.

The obtained film was analyzed by ATR-IR, and it was confirmed that no peaks derived from organic substances such as ethyl groups contained in the solvent contained in Composition O or the partial hydrolyzate of triethyl aluminum were observed, and the formation of an aluminum oxide film was confirmed.

The adhesion of the film obtained at 100°C and 130°C was confirmed by the same test as in Example 2-21, and no peeling of the strong film was observed, and it was confirmed that the film formed from the present composition had high adhesion.

[Example 2-26]

3.43 g of the composition O prepared in Example 2-21 was weighed under a nitrogen atmosphere, and 2.29 g of toluene was added and stirred to obtain a uniform solution. This homogeneous solution was used as a composition for producing an aluminum oxide film (composition P) containing a product obtained by partially hydrolyzing triethylaluminum. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

[Example 2-27]

To 10.0 g of toluene, 3.13 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 2.46 g of a THF solution containing 0.49 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) became 1.0. Then, it was made to react at 25 degreeC for 18 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition Q) was obtained.

[Example 2-28]

To 10.0 g of toluene, 5.83 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 4.55 g of a THF solution containing 0.91 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) became 1.0. Then, it was made to react at 25 degreeC for 18 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution containing white insoluble matter. The white insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition R) was obtained.

[Example 2-29]

To 10.0 g of toluene, 12.3 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 8.13 g of a THF solution containing 1.63 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) became 1.0. Then, it was made to react at 25 degreeC for 18 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution containing white insoluble matter. The white insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition S) was obtained.

[Example 2-30]

To 10.0 g of tetrahydrofuran (THF), 1.31 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 1.03 g of a THF solution containing 0.21 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) became 1.0. Then, it was made to react at 25 degreeC for 18 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution containing white insoluble matter. The white insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition T) was obtained.

[Example 2-31]

To 10.0 g of tetrahydrofuran (THF), 5.83 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 4.58 g of a THF solution containing 0.92 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) became 1.0. Then, it was made to react at 25 degreeC for 18 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution containing white insoluble matter. The white insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition U) was obtained.

[Example 2-32]

To 20.0 g of tetrahydrofuran (THF), 2.22 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 3.50 g of a THF solution containing 0.42 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) was 1.2. After that, the temperature was raised to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution containing a small amount of insoluble matter in the form of a gel. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition V) was obtained.

This composition V was applied on the surface of a 18 mm square (thickness: 0.7 mm) glass substrate (EagleXG (registered trademark), manufactured by Corning) by a spin coating method. 50 μl of the above solution was dropped onto the glass substrate at room temperature under a nitrogen atmosphere, and the substrate was rotated at a rotation speed of 1000 rpm for 20 seconds to apply the solution to the entire glass substrate. After drying at room temperature, the substrate was placed at a predetermined temperature By heating for 2 minutes, the solvent was dried and a film was formed at the same time.

The substrate with this film was taken out into the air, and the obtained film was analyzed by ATR-IR to confirm formation of an aluminum oxide film. All of the obtained films were transparent with high transmittance, and the vertical transmittance at 550 nm of the films obtained by heating at each temperature obtained values shown in Table 2-6. In addition, when the film thickness of the film heated at 130 DEG C was measured with a stylus-type surface profilometer, it was 178 nm.

[Table 2-6]

[Example 2-33]

In Example 2-32, the coating film operation was repeated three times, and a film was similarly obtained at 300°C. The vertical transmittance at 550 nm of the aluminum oxide film obtained by heating at 300°C obtained a value of 85%.

[Example 2-34]

To 20.0 g of tetrahydrofuran (THF), 1.05 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature (25°C). To the TEAL/THF solution obtained by sufficiently stirring, while paying attention to heat generation, 1.66 g of a THF solution containing 0.20 g of water was added dropwise while stirring so that the molar ratio of water to TEAL (water/TEAL) was 1.2. After that, the temperature was raised to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution containing a small amount of insoluble matter in the form of a gel. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed. In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition W) was obtained. Using this composition W, a coating film was formed on a glass substrate in the same manner as in Example 2-33, and the results shown in Table 2-7 were obtained. In addition, when the film thickness of the film heated at 130 DEG C was measured with a stylus-type surface profilometer, it was 146 nm.

[Table 2-7]

[Example 2-35]

In Example 2-34, the coating film operation was repeated three times to obtain a film similarly at 300°C. The vertical transmittance at 550 nm of the aluminum oxide film obtained by heating at 300°C obtained a value of 92%.

[Example 2-36]

Using the composition for producing an aluminum oxide film (composition D) containing a product obtained by partially hydrolyzing triethylaluminum and having a molar ratio of water to TEAL (water/TEAL) obtained in Examples 2-7 to be 1.06, A polypropylene (PP) film (30 mm square (thickness: 0.2 mm)) was used as a substrate for forming an aluminum oxide film, and 200 µl of the solution was dropped onto the film at room temperature under a nitrogen atmosphere, and the film was rotated at a rotation speed of 500 rpm for 20 mm. The substrate was rotated for a second to apply the solution to the entire film, and after drying the solvent, the substrate was heated for 2 minutes at each temperature of 50, 100, and 130° C. to dry the solvent and form a film at the same time.

The substrate with these films was taken out into the atmosphere, and the resulting film was analyzed by ATR-IR. No peaks derived from organic substances such as solvent contained in composition D or ethyl group contained in partial hydrolyzate of triethyl aluminum were observed. and formation of an aluminum oxide film were confirmed. All films obtained at each temperature were transparent.

The adhesion of the film obtained by heating at each temperature was confirmed by a peel test using a cellophane tape having a width of 12 mm. A cellophane tape was pressed firmly onto the film-formed surface of the polypropylene (PP) film on which the aluminum oxide film was formed, and peeled off at an angle of 45°. When it was confirmed by visual observation, ATR-IR, and SEM measurement after peeling off, peeling of the strong film was not confirmed in any case, and it was confirmed that the film formed by the present composition had high adhesion even in heat treatment at a low temperature of 130 ° C. or less. . Among these, although it formed into a film especially at 130 degreeC, the film|membrane adhesiveness was good.

[Example 2-37]

Composition O obtained in Example 2-21, composition P obtained in Example 2-26, composition Q obtained in Example 2-27, composition R obtained in Example 2-28, composition T obtained in Example 2-30, A product obtained by partially hydrolyzing each triethylaluminum of composition U obtained in Example 2-31 (compositions O, P, Q, R, T and U all have a molar ratio of water to TEAL (water/TEAL) of 1.0) Using each composition for producing an aluminum oxide film containing , a film was applied by spin coating in the same manner as in Example 2-36, and after drying the solvent, the mixture was heated for 2 minutes at each temperature of 50, 100, and 130 ° C. , A film was formed on a polypropylene (PP) film (30 mm square (0.2 mm thick)). The substrates with these films attached were taken out into the atmosphere, and the obtained films were analyzed by ATR-IR. Peaks derived from organic substances such as solvents contained in each composition or ethyl groups contained in partial hydrolysates of triethylaluminum were not observed. and formation of an aluminum oxide film were confirmed.

[Example 2-38]

Composition D obtained in Examples 2-7 (molar ratio of water to TEAL (water/TEAL) is 1.06), composition E obtained in Examples 2-9 (molar ratio of water to TEAL (water/TEAL) is 0.4), Examples Composition F obtained in 2-10 (molar ratio of water to TEAL (water/TEAL) is 0.6), composition G obtained in Example 2-11 (molar ratio of water to TEAL (water/TEAL) is 0.8), Example 2- Composition H obtained in 12 (molar ratio of water to TEAL (water/TEAL) is 1.17) and composition I (molar ratio of water to TEAL (water/TEAL) is 1.25) obtained in Examples 2-13 were partially mixed with triethylaluminum. Each composition for producing an aluminum oxide film containing a product obtained by hydrolysis was used to form a film by spin coating in the same manner as in Example 2-36, and after drying the solvent, the temperature of 50, 100, and 130 ° C. was heated for 2 minutes, and a film was formed on a polypropylene (PP) film (30 mm square (0.2 mm thick)).

Polypropylene (PP) films with these films attached were taken out into the atmosphere, and the obtained films were analyzed by ATR-IR to determine the origin of solvents contained in each composition or organic substances such as ethyl groups contained in partial hydrolysates of triethylaluminum. It was confirmed that the peak of was not confirmed and the formation of an aluminum oxide film. All films obtained at each temperature were transparent.

Further, the adhesion of the obtained film was confirmed by a peel test using Scotch Tape (registered trademark) 2364 (manufactured by 3M Co.) used in the cross-cut test of Example 2-7. A tape was pressed and attached to the film formation surface of the polypropylene (PP) film on which an aluminum oxide film was formed, and then peeled off at an angle of 45°. When it was confirmed by visual observation, ATR-IR, and SEM measurement after peeling off, peeling of the strong film was not confirmed, and it was confirmed that the film formed by the present composition had high adhesion. For these obtained films, composition D (molar ratio of water to TEAL (water/TEAL) is 1.06), composition G (molar ratio of water to TEAL (water/TEAL) is 0.8), composition H (molar ratio of water to TEAL (water/TEAL) TEAL) is 1.17) and composition I (molar ratio of water to TEAL (water/TEAL) is 1.25), and the film obtained by heating at 100° C. or higher has good adhesion to the polypropylene (PP) film. did Each ATR-IR spectrum of the aluminum oxide film before and after the peel test was performed on the aluminum oxide film formed on the PP film at 100 ° C. using the composition H (molar ratio of water to TEAL (water / TEAL) is 1.17). 2q and Fig. 2r (Fig. 2q: before peeling test, Fig. 2r: after peeling test).

[Comparative Example 2-6]

In Example 2-1, instead of 36.6 g of a THF solution containing 108.45 g of tetrahydrofuran (THF), 15.13 g of triethyl aluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) and 1.08 g of water, The reaction was carried out using the same method as in Example 2-1, except that 48.8 g of a THF solution containing 0.48 g of water was added dropwise so that the molar ratio of water to TEAL (water/TEAL) was 0.2. got Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film (composition 3) containing a product obtained by partially hydrolyzing triethylaluminum was obtained.

As a substrate for forming an aluminum oxide film using a composition (composition 3) containing a product obtained by partially hydrolyzing triethylaluminum and having a molar ratio of water to TEAL (water/TEAL) of 0.2, Using a polypropylene (PP) film (30 mm square (0.2 mm thick)), an aluminum oxide film was formed by spin coating in the same manner as in Example 2-1. At this time, after application of Composition 3 and drying of the solvent, the film was heated for 2 minutes at each temperature of 130°C. The substrate with the film obtained by heating at each of these temperatures was taken out into the air, and the obtained film was analyzed by ATR-IR to obtain the spectrum shown in Fig. 2S. As is clear from Fig. 2s, compared to Fig. 2q of Example 2-38, the peak derived from the PP substrate is larger than the peak of aluminum oxide, the molar ratio of water to TEAL (water/TEAL) is set to 0.2, and the tri It was confirmed that the aluminum oxide film obtained by film formation using the composition for producing an aluminum oxide film (composition 3) containing a product obtained by partially hydrolyzing ethyl aluminum was thinner than the film obtained by film formation using the composition of the present invention.

Further, the adhesiveness of the obtained film was subjected to a peel test using Scotch Tape (registered trademark) 2364 (manufactured by 3M) used in the cross-cut test of Example 2-7, and analyzed by ATR-IR and SEM measurements. FIG. 2t shows the ATR-IR spectrum of the aluminum oxide film formed on the PP film using Composition 3 at 100° C. after performing a peeling test. From this, it was confirmed that not only was there little adhesion of oxide during film formation, but also that the film was easily peeled off.

As such, the product obtained by partially hydrolyzing triethylaluminum so that the molar ratio of water to TEAL (water/TEAL) used in this comparative example was 0.2 was obtained by partially hydrolyzing water to TEAL (water/TEAL) used in Examples 2-38. ) was confirmed to be inferior in film formability and adhesion to the composition obtained at 0.4 to 1.25.

[Comparative Example 2-7]

90 ml of isopropanol was added to 18.38 g of aluminum triisopropoxide, and 1.62 g of water was added dropwise at room temperature while stirring so that the molar ratio to aluminum triisopropoxide became 1. After that, the temperature was raised to 80°C and reacted at 80°C for 3 hours. After completion of the reaction, it was cooled and the content was recovered, but most of the aluminum triisopropoxide was recovered as an unreacted material.

[Comparative Example 2-8]

109.25 g of water was heated to 72° C. and 41.8 g of aluminum triisopropoxide was added with stirring. It heated at 85 degreeC for 4 hours, and then stood to cool to room temperature. The solution was in the form of a gel and was difficult to stir. Further, 1.89 g of 60% by weight of nitric acid was added to obtain a white gel-like substance. This solution was heated at 91 °C for 3 hours. After that, it was allowed to cool to room temperature to obtain a gel-like substance. Since the dispersion of this gel-like substance in the liquid was poor, 200 g of water was added to dilute it, and it was collected as a translucent milky white cloudy liquid (composition 4).

As a substrate for forming an aluminum oxide film, a polypropylene (PP) film (30 mm square (thickness: 0.2 mm)) was used, and composition 4 was used, and the same operation as in Example 2-1 was performed, followed by spin coating film formation. , an aluminum oxide film was formed. At this time, after application of Composition 4 and drying of the solvent, the film was heated at 130° C. for 2 minutes. Composition 4 hardly remained on the film surface, and a film could not be formed. Film formation by immersion coating was similarly attempted, but film formation could not be performed as in spin coating. Further, an attempt was made to form an aluminum oxide film by spreading the composition 4 on a polypropylene (PP) film as much as possible and then heating it at 60° C., but a transparent film-like material was formed piecemeal, but all peeled off from the film.

Results are shown in Tables 2-8 and 2-9 for evaluating the adhesion of films obtained by forming films by spin coating on PP films using the respective compositions obtained in Examples 2-38 and Comparative Examples 2-2 and 2-6.

[Table 2-8]

[Table 2-9]

[Example 2-39]

In Example 2-13, when the water/THF solution was added dropwise so that the molar ratio of water to TEAL (water/TEAL) was 1.27 or 1.29, white insoluble matter was generated (10% by volume of solid occupied in the solution). below). When the appearance of the composition was observed after leaving the solution at room temperature (20 to 25 ° C.) for 3 days, there was almost no increase in white insoluble matters generated when water/THF solution was additionally added, and by removing these insoluble matters, triethyl A composition for producing an aluminum oxide film was obtained as a homogeneous solution containing a product obtained by partially hydrolyzing aluminum (composition X (water/TEAL = 1.27) and composition Y (water/TEAL = 1.29). These compositions are An aluminum oxide film could be formed by coating on a substrate such as glass or resin by the spin coating film formation or dip coating film formation described in Examples of Invention 2 and further heating. , The molar ratio of water to TEAL (water/TEAL) is 0.4 to 1.25, respectively, and also for the composition for preparing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum, the solution is 3 at room temperature (20 to 25 ° C.) When the external appearance of the composition after standing for one day was visually observed, no change was observed in the solution.

[Comparative Example 2-9]

In Example 2-13, when the water/THF solution was additionally added dropwise so that the molar ratio of water to TEAL (water/TEAL) was 1.31, 1.33 or 1.35, a large amount of white insoluble matter was generated (volume occupied in the solution). by 15% or more). When the external appearance of the composition was observed after leaving the solution for 3 days, the entire solution was gel-shaped, there was almost no homogeneous solution portion, and the fluidity as a solution was almost lost. In such a case where the molar ratio of water to TEAL (water/TEAL) is high, it is not possible to obtain a composition as a uniform solution, making it difficult to use it as a coating agent.

In Example 2-39 and Comparative Example 2-9, the appearance of the reaction product obtained by partial hydrolysis of TEAL in each water / TEAL (molar ratio) and the generation of insoluble gel (immediately after preparation and after standing for 3 days) For Table 2-10 and Table 2-11, the results are shown.

[Table 2-10]

[Table 2-11]

[Example 2-40]

Using the composition for producing an aluminum oxide film (composition D) containing a product obtained by partially hydrolyzing triethylaluminum and having a molar ratio of water to TEAL (water/TEAL) obtained in Examples 2-7 to be 1.06, Using paper (approximately 20 mm square (thickness: 31 μm)) as a substrate for forming an aluminum oxide film, coating was performed by a dip coating method. The paper was immersed in Composition D for 1 second under a nitrogen atmosphere, and the paper After pulling up, the liquid collected on the paper was dropped. After the solvent was dried at room temperature, it was heated at 200 ° C. for 2 minutes to form a film on the paper. Analysis was carried out by this method, and it was confirmed that peaks derived from organic substances such as ethyl groups contained in the solvent contained in the composition D or the partial hydrolyzate of triethylaluminum were not observed, and the formation of an aluminum oxide film was confirmed. , Fig. 2u was obtained, and it was confirmed that the surface of the fiber of the paper was coated with aluminum oxide.

[Example 2-41]

In Example 2-40, as a substrate for forming an aluminum oxide film, instead of paper (about bag: (20 mm square (thickness: 31 μm))), a glass substrate of 18 mm square (0.7 mm thick) (Corning Co., EagleXG (registered) Trademark)) was applied by the dip coating method. Under a nitrogen atmosphere, the glass substrate was immersed in the composition D for 1 second, the glass substrate was pulled up, and then the liquid accumulated on the substrate was dropped. The solvent was room temperature. After drying, a film was formed on the substrate by heating at 130 ° C. for 2 minutes, in a nitrogen gas atmosphere during the series of film formation operations of coating, solvent drying and heating, the moisture content was 246 to 304 ppm (dew point temperature -32 to 34° C.).

The obtained film-attached substrate was taken out into the air, and the obtained film was analyzed by ATR-IR, and no peaks derived from organic substances such as the solvent contained in the composition D or the ethyl group contained in the partial hydrolyzate of triethylaluminum were observed. and the formation of an aluminum oxide film was confirmed. The appearance of the obtained aluminum oxide film was transparent and homogeneous.

[Comparative Example 2-10]

In Example 42-1, in a nitrogen gas atmosphere during a series of film formation operations of coating, solvent drying, and heating, the water content was 9312 mol ppm to 9778 ppm (about 1%) (dew point temperature -6 to -7 °C), a film was formed on a glass substrate in the same manner as in Example 2-41, except that the film was formed.

The obtained film-attached substrate was taken out into the air, and the obtained film was analyzed by ATR-IR, and no peaks derived from organic substances such as the solvent contained in the composition D or the ethyl group contained in the partial hydrolyzate of triethylaluminum were observed. However, a part of the obtained aluminum oxide film was in the form of a powder, and a homogeneous film could not be obtained.

[Example 2-42]

Any substrate with an aluminum oxide film obtained in Examples 2-1, 2-2, 2-3, 2-4, 2-5, 2-15, 2-32, 2-33, and 2-34, 550 The vertical transmittance at nm is as high as 80% or more, so it can be used as an optical material. Further, even if the aluminum oxide film formed on the glass substrate is further heated at 500° C. after film formation, deterioration is not observed, and it can be used as a heat-resistant material. When the surface resistance values of these films were measured, no resistance values were obtained and no conductivity was obtained, so that they could be used as insulating materials. The base material with an aluminum oxide film of Example 2-24 was confirmed to have minute irregularities on the surface of the film obtained by film formation, and it could be used as an antireflection effect and as a catalyst carrier. In Examples 2-7, 8, 21, 22, 23, 24, 25, 36, 37, 38, and 40, the aluminum oxide film formed from the composition of the present invention has high adhesion to substrates such as glass, resin, and paper. Therefore, it is possible to use undercoat films such as protective films for various substrates, undercoats for painting and laminated films, films for electronic devices that can be laminated on substrates, and the like. In this way, the substrate with an aluminum oxide film of the present invention can be used as an aluminum oxide functional film.

[Example 2-43]

The glass substrate provided with the aluminum oxide film of Example 2-1, 2, 3, 4, 5, 6, 15, 24, 32, 33, 34, 35 and 39, Example 2-7, 8, 21, 22, 23, 25, 36, 37, 38, 39 and 40, polypropylene (PP), polyethylene terephthalate (PET), and resin plates and films and papers provided with an aluminum oxide film, such as acrylic, are all It can be used as a substrate having an aluminum oxide functional film having the function described in Example 42.

<Third aspect of the present invention>

Preparation of solutions containing all of the organoaluminum compounds and film formation using them were conducted under a nitrogen gas atmosphere, and all solvents were dehydrated and degassed before use.

<Number of moles of triethylaluminum>

It is the same as the first aspect of the present invention.

Water during film formation on the aluminum oxide film is formed in a state in which water is saturated in nitrogen (25 mol% as water in inert gas) by bubbling nitrogen into water heated to 65 ° C. as necessary. The moisture content in the inert gas in the film formation atmosphere can be determined by dew point measurement (humidity).In the case of preparing a solution or film formation, etc., when carried out at room temperature, the room temperature is 18 to 27 ° C. It was carried out under the same environment as

Formation of aluminum oxide and its film on the substrate in each film formation in Examples and Comparative Examples is ATR-IR (infrared spectroscopy by an attenuated total reflection (ATR) method), EPMA (Electron Probe Microscope) Analyzer: electron beam microanalyzer) and XRD (X-ray diffraction: X-ray diffraction) analysis was confirmed.

The transmittance of visible light or the like was measured using a spectrophotometer.

The film thickness of the aluminum oxide film was measured by a stylus-type surface profilometer or by SEM measurement of a cross section of the thin film.

Adhesion of the formed aluminum oxide film to the substrate was confirmed by a peeling test by tape application and peeling to the aluminum oxide film formed by coating the film on the substrate using an adhesive tape.

As for the reactivity of the chemical solution, the chemical solution was dropped onto the filter paper in a windless atmosphere at a constant temperature (20° C.) and humidity (50%), and the reactivity on the filter paper was visually confirmed.

[Example 3-1-1]

To 74.8 g of tetrahydrofuran (THF), 8.3 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. After sufficient stirring, a solution for producing an aluminum oxide film containing triethylaluminum for use in spray coating was obtained by filtering (solution A).

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution A), an aluminum oxide film was formed by spray film formation. As a base material on which an aluminum oxide film is formed, a glass substrate (EagleXG (registered trademark), manufactured by Corning) of 18 mm square (thickness: 0.7 mm) is used. In a nitrogen atmosphere in which water was present at 2.3 mol% (21° C., 90% relative humidity), solution A was sprayed from a spray nozzle at a rate of 2 ml/min for 8 minutes to a substrate heated by a heater. The size of the droplet discharged from the spray nozzle was in the range of 3 to 20 μm, and the distance between the spray nozzle and the substrate was set to 20 cm. After the end of the spraying, heating of the film-formed substrate was continued for 5 minutes.

The film formed on the glass substrate was taken out into the air after cooling, and analyzed by SEM and EPMA to confirm that the film was attached and that the elements constituting the film were oxygen and aluminum elements, and further analyzed by ATR-IR, 550 to 1000 cm ^-1 and an increase in the peak overlapping with the peak derived from the glass substrate around 2800 to 3100 cm ^-1 , and a peak attributed to that derived from CH in the structure of the organoaluminum compound or solvent is not observed. confirmed that From the above analysis, formation of an aluminum oxide film at a low temperature of 200°C was confirmed by the film formation method using this solution. In addition, it was confirmed that the aluminum oxide film obtained in this example was in an amorphous state, with no peak observed by XRD. The film thickness of the aluminum oxide film was 329 nm as measured by a stylus type surface profilometer. In addition, the transmittance in visible light (550 nm) was 97.9%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

The film formation described in Example 3-1-1 was performed again using a solution having the same composition as the solution for producing an aluminum oxide film containing triethylaluminum (solution A) of Example 3-1-1, A film thickness of 332 nm of aluminum oxide film was obtained. This film was analyzed by SEM, and it was confirmed that the surface structure of the film was the shape shown in Fig. 3B and the cross-sectional structure of the film was shown in Fig. 3C.

[Example 3-1-2]

In Example 3-1-1, 76.5 g of tetrahydrofuran (THF) and 4.0 g of triethylaluminum (manufactured by Tosoh FineChem Co., Ltd.) were carried out in the same manner as in Example 3-1-1, and sprayed. A solution for producing an aluminum oxide film containing triethylaluminum (solution B) for use in coating was obtained.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution B), the same operation as in Example 3-1-1 was performed to form an aluminum oxide film by spraying. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 279 nm. The transmittance of the obtained film in visible light (550 nm) was 94.8%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-3]

In Example 3-1-1, 79.2 g of 1,2-diethoxyethane was used instead of tetrahydrofuran (THF), and 8.8 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was carried out. The same operation as in Example 3-1-1 was performed to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution C) for use in spray coating.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained aluminum oxide film production solution (solution C), the same operation as in Example 3-1-1 was performed, and the aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 358 nm. In addition, the transmittance in visible light (550 nm) was 95.3%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-4]

In Example 3-1-1, using 82.7 g of diisopropyl ether instead of tetrahydrofuran (THF), using 9.2 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.), Example 3-1 The same operation as in -1 was carried out to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution D) for use in spray coating.

Using the obtained solution for producing an aluminum oxide film (solution D), the same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 307 nm. In addition, the transmittance in visible light (550 nm) was 97.6%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-5]

In Example 3-1-1, using a mixed solvent of 41.3 g of tetrahydrofuran (THF) and 41.3 g of hexane instead of tetrahydrofuran (THF), triethyl aluminum (manufactured by Tosoh Finechem Co., Ltd.) was added to 9.2 As g, the same operation as in Example 3-1-1 was carried out to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution E) for use in spray coating.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution E), the same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 211 nm. In addition, the transmittance in visible light (550 nm) was 97.6%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-6]

In Example 3-1-1, using a mixed solvent of 21.9 g of tetrahydrofuran (THF) and 51.0 g of toluene instead of tetrahydrofuran (THF), triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added to 8.1 As g, the same operation as in Example 3-1-1 was carried out to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution F) for use in spray coating.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution F), the same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 271 nm. In addition, the transmittance in visible light (550 nm) was 95.5%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-7]

In Example 3-1-4, using a mixed solvent of 41.2 g of diisopropyl ether and 41.2 g of mixed xylene instead of diisopropyl ether, 9.1 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) Then, the same operation as in Example 3-1-4 was carried out to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution G) for use in spray coating.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution G), the same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 330 nm. In addition, the transmittance in visible light (550 nm) was 93.9%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-8]

In Example 3-1-3, using a mixed solvent of 62.3 g of 1,2-diethoxyethane and 15.6 g of mixed xylene instead of 1,2-diethoxyethane, triethyl aluminum (tosoh pine) Chem Co., Ltd.) was used as 8.7 g, and the same operation as in Example 3-1-3 was performed to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution H) for use in spray coating.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution H), the same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spraying. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 281 nm. In addition, the transmittance in visible light (550 nm) was 94.4%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-9]

In Example 3-1-8, triethyl An aluminum oxide film production solution (solution I) containing triethyl aluminum for use in spray coating by carrying out the same operation as in Example 3-1-8 using 8.9 g of aluminum (manufactured by Tosoh FineChem Co., Ltd.) got

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Using the obtained solution for producing an aluminum oxide film (solution I), the same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film at a low temperature of 200 DEG C was confirmed by the film formation method using this solution. The film thickness of the aluminum oxide film formed on the glass substrate was 310 nm. In addition, the transmittance in visible light (550 nm) was 94.3%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-10]

In Example 3-1-1, as a substrate on which an aluminum oxide film is formed, a polyethylene terephthalate (PET) film (all sides) instead of a 18 mm square (thickness 0.7 mm) glass substrate (EagleXG (registered trademark) manufactured by Corning)) 60 mm (thickness: 75 µm)), the same operation as in Example 3-1-1 was performed under the condition that the heating temperature of the base material was changed from 200 ° C. to 130 ° C., and the aluminum oxide film production solution (solution A) An aluminum oxide film was formed on a polyethylene terephthalate (PET) film heated to 130°C by spray film formation using a solution having the same composition as above. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film on a polyethylene terephthalate (PET) film at a low temperature of 130 DEG C was confirmed by the film formation method using this solution. The SEM measurement results for the surface structure of the obtained film are shown in FIG. 3D. The transmittance of this aluminum oxide film in visible light (550 nm) was 86%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

[Example 3-1-11]

In Example 3-1-10, as a substrate for forming an aluminum oxide film, instead of a polyethylene terephthalate (PET) film (60 mm square (25 μm thick)), a porous polypropylene (PP) film (for a secondary battery separator) : Using a 60 mm square (20 μm thick)), heating this film at 130 ° C., using a solution having the same composition as the solution for producing an aluminum oxide film (solution A), the same as in Example 3-1-10 The operation was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film on a polypropylene (PP) porous film at a low temperature of 130° C. was confirmed by the film formation method using this solution.

[Example 3-1-12]

In Example 3-1-10, as a substrate for forming an aluminum oxide film, instead of a polyethylene terephthalate (PET) film (60 mm square (75 μm thick)), an aramid nonwoven fabric (secondary battery separator specification: 60 mm square ( thickness of 57 μm)), the film was heated to 130° C., and the same operation as in Example 3-1-10 was performed using a solution having the same composition as the solution for producing an aluminum oxide film (solution A), followed by spraying. By film formation, an aluminum oxide film was formed.

By similar analysis of the film formed on the substrate, the formation of an aluminum oxide film on the aramid porous film at a low temperature of 130°C was confirmed by the film formation method using this solution.

[Example 3-1-13]

To 150.0 g of tetrahydrofuran (THF), 15.0 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. After sufficient stirring, the solution was filtered through a filter (pore: 3 μm or less) to obtain a solution for producing an aluminum oxide film containing triethylaluminum (solution J) for use in spray coating.

Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

As a substrate for forming an aluminum oxide film, a polypropylene (PP) film (30 mm square (thickness: 0.2 mm)) is used, the film is heated to 130 ° C., and a solution for producing an aluminum oxide film (solution J) is used, The same operation as in Example 3-1-1 was performed, and an aluminum oxide film was formed by spray film formation. By similar analysis of the film formed on the substrate, formation of an aluminum oxide film on the polypropylene (PP) film at a low temperature of 130°C was confirmed by the film formation method using this solution.

[Example 3-1-14]

A solution for preparing an aluminum oxide film (solution K) consisting of 69.7 g of tetrahydrofuran (THF) and 2.16 g of triethyl aluminum (manufactured by Tosoh Finechem Co., Ltd.) with a low content of triethyl aluminum and a low content of triethyl aluminum A solution (solution L) for producing an aluminum oxide film composed of 69.7 g of tetrahydrofuran (THF) and 0.70 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was prepared by the same method as in Example 3-1-1, When film formation was performed on the heating temperature of the glass substrate under the conditions described in Example 3-1-1 at 200°C, formation of an aluminum oxide film at 200°C was confirmed.

In addition, it was confirmed that the aluminum oxide film obtained in this example was in an amorphous state, with no peak observed by XRD. The transmittance in visible light (550 nm) and the film thickness of the aluminum oxide film obtained by spray deposition using the respective solutions of solution K and solution L were 99%, 75 nm (solution K), 99%, and 30 nm, respectively. (Solution L).

[Example 3-1-15]

In Example 3-1-1 and Example 3-1-2, the aluminum oxide film production solution obtained in each Example (Solution A: Example 3-1-1, Solution B: Example 3-1- Using 2), the heating temperature of the glass substrate was changed to 300 ° C., the same operation was performed, and the formation of an aluminum oxide film at 300 ° C. was confirmed by the film forming method using this solution by the same analysis. The aluminum oxide film obtained in this example was confirmed to be in an amorphous state, with no peak observed by XRD.

[Example 3-1-16]

The adhesion of the films obtained in Examples 3-1-1 to 10 was confirmed by a peel test using Scotch Tape (registered trademark) 2364 (manufactured by 3M Corporation). A tape was pressed and attached to the film formation surface of the polypropylene (PP) film on which an aluminum oxide film was formed, and then peeled off at an angle of 45°. When it was confirmed by visual observation, ATR-IR, and SEM measurement after peeling off, peeling of the strong film was not confirmed, and it was confirmed that the film formed by the present composition had high adhesion.

[Example 3-1-17]

As a substrate for forming an aluminum oxide film, paper (approximately 20 mm square (thickness 31 μm)) was used, the paper was heated to 142 ° C., and the aluminum oxide film production solution prepared in Example 3-1-4 ( Using the solution D), the same operation as in Example 3-1-1 was carried out, and an aluminum oxide film was formed by spray deposition.The film formation method using this solution was analyzed in the same way as the film formed on the paper. This confirmed the formation of an aluminum oxide film on paper at a low temperature of 142°C.

As a result of SEM analysis of the obtained film, Fig. 3E was obtained, and it was confirmed that the surface of the fibers of the paper was coated with aluminum oxide in the form of particles.

[Example 3-1-18]

Any of the substrates with aluminum oxide films obtained in Examples 3-1-1 to 10 and 14 had a vertical transmittance as high as 80% or more at 550 nm, and could be used as optical materials. In addition, the aluminum oxide film formed on the glass substrate does not change in quality even when heated at 500°C, and can be used as a heat-resistant material. When the surface resistance values of the films obtained in Examples 3-1-1 to 15 and 17 were measured, no resistance value was obtained and no conductivity was obtained, so that the films could be used as an insulating material. The substrates with aluminum oxide films of Examples 3-1-1, 10, and 17 were confirmed to have minute irregularities on the surface of the films obtained by film formation, and were effective in antireflection and were usable as catalyst carriers. In Examples 3-1-1 to 10 and 17, since the aluminum oxide film formed from the composition of the present invention has high adhesion to substrates such as glass and resin, it can be used as a protective film for various substrates, as well as undercoats for painting and laminated films. A film, a film for electronic devices that can be laminated on a substrate, and the like can be used. In this way, the substrate with an aluminum oxide film of the present invention can be used as an aluminum oxide functional film.

[Example 3-1-19]

Glass substrates provided with the aluminum oxide films described in Examples 3-1-1 to 9, 14 and 15, polypropylene (PP) and polyethylene terephthalate (PET) provided with the aluminum oxide films obtained in Examples 10 to 13, The board and film of a resin such as acrylic and the paper provided with the aluminum oxide film obtained in Example 3-1-17 can all be used as a substrate having the aluminum oxide functional film having the function described in Example 3-1-18. It is possible.

[Comparative Example 3-1-1]

In Example 3-1-2, hexane was used instead of tetrahydrofuran (THF), and the same operation as in Example 3-1-2 was carried out to obtain aluminum containing triethylaluminum for use in spray coating. A solution for producing an oxide film (solution X) was obtained.

Using this electron-donating solvent-free solution (solution K), the same operation as in Example 3-1-1 was carried out to form an aluminum oxide film by spray deposition, but the powdery substance was deposited on the substrate. It was just attached. In addition, there was almost no powdery substance adhering to the substrate, and the aluminum oxide film was not formed.

[Comparative Example 3-1-2]

In Example 3-1-1, the substrate heated by a heater was heated by a heater in a nitrogen atmosphere containing 0.003 mol% (relative humidity at 21°C, 0.1%) of moisture in the inert gas at atmospheric pressure and substantially no moisture. , Solution A was sprayed at 2 ml/min for 8 minutes from a spray nozzle. An aluminum oxide film was formed by spray filming in the same manner as in Example 3-1-1, but there was almost no deposit on the substrate, and the obtained film was placed in a nitrogen atmosphere containing water at a relative humidity of 90% after completion of the film formation. Although heating was performed at 200°C under the condition, since almost no substance adhered to the substrate, formation of an aluminum oxide film could not be confirmed similarly.

[Comparative Example 3-1-3]

To 86.41 g of toluene, 4.32 g of aluminum trisacetylacetonate (Al(acac) ₃ ) was added at room temperature. After sufficiently stirring, the solution is filtered with a filter (pore: 3 μm or less) to prepare an aluminum oxide film containing aluminum trisacetylacetonate (Al(acac) ₃ ) for use in spray coating (solution L) got

The same operation as in Example 3-1-1 was carried out using a solution (solution Y) containing an organoaluminum compound that does not contain this straight-chain or branched alkyl group having 1 to 3 carbon atoms in the structure of the organoaluminum compound, and sprayed. By film formation, an aluminum oxide film was formed.

Using this electron-donating solvent-free solution (solution L), the same operation as in Example 3-1-1 was carried out, and the film was formed by spraying at a heating temperature of the substrate of 200 ° C. There was almost no deposit on the surface, and no aluminum oxide film was formed.

[Comparative Example 3-1-4]

To 90.19 g of toluene, 4.51 g of aluminum triisopropoxide (Al(O ⁱ Pr) ₃ ) was added at room temperature. After sufficiently stirring, the solution is filtered with a filter (pore: 3 μm or less) to prepare an aluminum oxide film containing aluminum triisopropoxide (Al(O ⁱ Pr) ₃ ) for use in spray coating ( Solution Z) was obtained.

The same operation as in Example 3-1-1 was carried out using a solution (solution M) containing an organoaluminum compound that does not contain a straight-chain or branched alkyl group having 1 to 3 carbon atoms in the structure of the organoaluminum compound, and the substrate Although the film was formed by spray filming at a heating temperature of 200°C, there was almost no deposit on the substrate and no aluminum oxide film was formed.

[Example 3-2-1]

To 108.45 g of tetrahydrofuran (THF), 15.13 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 48.8 g of a THF solution containing 0.48 g of water was stirred so that the molar ratio of water to TEAL (water/TEAL) was 0.2 while removing heat generated by the reaction so that the temperature was around 20°C. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition A) was obtained.

Using this composition A, an aluminum oxide film was formed by a spray pyrolysis method. As a base material on which an aluminum oxide film is formed, a glass substrate (EagleXG (registered trademark), manufactured by Corning) of 18 mm square (thickness: 0.7 mm) is used. In a nitrogen atmosphere in which water was present at 2.3 mol% (21° C., 90% relative humidity), solution A was sprayed from a spray nozzle at a rate of 2 ml/min for 8 minutes to a substrate heated by a heater. The molar ratio of water as an oxygen source supplied at the time of this film formation to the number of moles of Al in the composition A was 90. The size of the droplet discharged from the spray nozzle was in the range of 3 to 20 μm, and the distance between the spray nozzle and the substrate was set to 20 cm. After the end of the spraying, heating of the film-formed substrate was continued for 5 minutes.

The film formed on the glass substrate was taken out into the air after cooling and analyzed by SEM and EPMA to confirm adhesion of the film and that the elements constituting the film were oxygen and aluminum elements. The results of SEM analysis of the surface of the film obtained in this example in FIG. 3G and the cross section of the film in FIG. 3H are respectively shown. In addition, as a result of analysis by ATR-IR, an increase in the peak overlapping with a peak derived from a glass substrate around 550 to 1000 cm ^-1 and an organic aluminum compound or solvent seen between 2800 and 3100 cm ^-1 in their structure It was confirmed that no peak attributed to CH origin was observed. From the above analysis, formation of an aluminum oxide film at a low temperature of 200°C was confirmed by the film formation method using this solution. In addition, it was confirmed that the aluminum oxide film obtained in this example was in an amorphous state, with no peak observed by XRD. The film thickness of the aluminum oxide film was 146 nm as measured by a stylus-type surface profilometer. In addition, the transmittance in visible light (550 nm) was 91.0%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

Regarding the adhesion of the obtained film, a cross-cut test and a peeling test using Scotch Tape (registered trademark) 2364 (manufactured by 3M Co.) used therein were conducted, and confirmed visually and by ATR-IR and SEM measurements, confirming that there is no peeling of the film, etc. did

[Example 3-2-2]

In Example 3-2-1, the same method as in Example 3-2-1 except that 0.95 g of water was added dropwise instead of 0.48 g of water so that the molar ratio of water to TEAL (water/TEAL) was 0.4. Using this, a colorless and transparent solution was obtained. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition B) was obtained. Using this composition B, an aluminum oxide film was formed by a spray pyrolysis method in the same manner as in Example 3-2-1. By analysis similar to Example 3-2-1, formation of an aluminum oxide film at a low temperature of 200°C was confirmed by the film forming method using the composition B. In addition, it was confirmed that the aluminum oxide film obtained in this example was in an amorphous state, with no peak observed by XRD. The film thickness of the aluminum oxide film was 119 nm as measured by a stylus-type surface profilometer. In addition, the transmittance in visible light (550 nm) was 84.3%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

Regarding the adhesion of the obtained film, a cross-cut test and a peel test using Scotch Tape (registered trademark) 2364 (manufactured by 3M) were conducted in the same manner as in Example 3-2-1, and visually and by ATR-IR and SEM measurements. As confirmed, it was confirmed that there was no peeling of the film or the like. The results of SEM analysis of the surface of the film obtained in this example in FIG. 3i and the cross section of the same film in FIG. 3j are respectively shown.

[Example 3-2-3]

In Example 3-2-1, the same method as in Example 3-2-1 except that 1.44 g of water was added dropwise instead of 0.48 g of water so that the molar ratio of water to TEAL (water/TEAL) was 0.6. Using this, a colorless and transparent solution was obtained. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition C) was obtained. Using this composition C, an aluminum oxide film was formed by a spray pyrolysis method in the same manner as in Example 3-2-1. By analysis similar to that in Example 3-2-1, formation of an aluminum oxide film at a low temperature of 200°C was confirmed by the film forming method using the composition C. In addition, it was confirmed that the aluminum oxide film obtained in this example was in an amorphous state, with no peak observed by XRD. The film thickness of the aluminum oxide film was 76 nm as measured by a stylus-type surface profilometer. In addition, the transmittance in visible light (550 nm) was 83.3%, and a transparent aluminum oxide film having a transmittance of 80% or more was obtained.

Regarding the adhesion of the obtained film, a cross-cut test and a peel test using Scotch Tape (registered trademark) 2364 (manufactured by 3M) were conducted in the same manner as in Example 3-2-1, and visually and by ATR-IR and SEM measurements. As confirmed, it was confirmed that there was no peeling of the film or the like.

[Comparative Example 3-2-1]

In Example 3-2-1, the same method as in Example 3-2-1 except that 1.91 g of water was added dropwise instead of 0.48 g of water so that the molar ratio of water to TEAL (water/TEAL) was 0.8. Using this, a colorless and transparent solution was obtained. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

Thus, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition D) was obtained. Using this composition D, an aluminum oxide film was formed by a spray pyrolysis method in the same manner as in Example 3-2-1, but deposits on the substrate were hardly seen and it was not possible to form a film.

[Comparative Example 3-2-2]

Composition A of Example 3-2-1 in Example 3-2-1, except that the amount of water added during hydrolysis was changed so that the molar ratio of water to TEAL (water/TEAL) was 1.0. A composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition E) was prepared in the same manner as in the preparation method of . Using this composition E, an aluminum oxide film was formed at 200° C. by spray pyrolysis in the same manner as in Example 3-2-1, but white powdery powder adhered to the substrate surface, resulting in poor adhesion. A good film could not be obtained.

Regarding the adhesion of the obtained film, a cross-cut test and a peel test using Scotch Tape (registered trademark) 2364 (manufactured by 3M) were conducted in the same manner as in Example 3-2-1, and visually and by ATR-IR and SEM measurements. As confirmed, it was confirmed that the powder in the form of white powder adhering to the surface of the substrate was peeled off. Table 3-1 shows the results of spray film formation using each composition prepared in Examples 3-2-1, 2, 3, and 4 and Comparative Example 3-2-1, respectively.

[Example 3-2-4]

To 73.2 g of tetrahydrofuran (THF), 11.35 g of triethylaluminum (TEAL: manufactured by Tosoh FineChem Co., Ltd.) was added at room temperature. To the TEAL/THF solution obtained by sufficiently stirring, 36.6 g of a THF solution containing 1.08 g of water was stirred so that the molar ratio of water to TEAL (water/TEAL) was 0.6 while removing heat generated by the reaction so that the temperature was around 20°C. I dropped it while doing it. After that, it was heated to 65°C and reacted at 65°C for 2.5 hours. After completion of the reaction, it was left to cool and the reaction product was recovered. The product after the reaction was a colorless and transparent solution. A trace amount of gel-like insoluble matter contained in this product was filtered through a filter (pore: 3 μm or less) to recover a colorless and transparent solution. Regarding the reactivity of the chemical solution, when the reactivity on the filter paper was visually confirmed, scorching of the filter paper or the like was not confirmed.

In this way, a composition for producing an aluminum oxide film containing a product obtained by partially hydrolyzing triethylaluminum (composition F) was obtained. ¹ H-NMR (THF-d ₈ , ppm) measurement was performed on a residue containing as a main component a product obtained by partially hydrolyzing triethyl aluminum after removing the solvent and the like from part of the composition F by vacuum drying. , obtained the spectrum in Fig. 3f. Using this composition F, an aluminum oxide film was formed by a spray pyrolysis method in the same manner as in Example 3-2-1. By analysis similar to Example 3-2-1, formation of an aluminum oxide film at a low temperature of 200°C was confirmed by the film forming method using the composition F.

[Example 3-2-5]

Using the composition A prepared in Example 3-2-1, as a substrate for forming an aluminum oxide film, a polypropylene (PP) film (30 mm square (thickness: 0.2 mm)) and a polyethylene terephthalate (PET) film (60 square mm) mm (thickness: 75 μm)), the heating temperature of the substrate was set to 130° C., and an aluminum oxide film was formed on each substrate by a spray pyrolysis method in the same manner as in Example 3-2-1. By analysis similar to Example 3-2-1, formation of an aluminum oxide film at a low temperature of 130°C was confirmed by the film forming method using the composition F.

[Comparative Example 3-2-3]

In Example 3-2-1, using the composition for producing an aluminum oxide film (composition A) containing a product obtained by partially hydrolyzing triethylaluminum, the moisture in the inert gas was 0.25 mol% (relative humidity at 21 ° C. 1%), an aluminum oxide film was formed by a spray pyrolysis method in the same manner as in Example 3-2-1 except that it was set in a nitrogen atmosphere in which water was present. In this film formation, there was almost no deposit on the glass substrate, and an aluminum oxide film could not be obtained.

[Example 3-2-6]

Any of the substrates with the aluminum oxide film obtained in Examples 3-2-1, 2, and 3 have a vertical transmittance as high as 80% or more at 550 nm, and can be used as an optical material. In addition, the aluminum oxide film formed on the glass substrate does not change in quality even if it is heated at 500° C. after film formation, and can be used as a heat-resistant material. When the surface resistance values of these films were measured, no resistance values were obtained and no conductivity was obtained, so that they could be used as insulating materials. In addition, since the aluminum oxide film formed from the composition of the present invention has high adhesion to substrates such as glass and resin, it can be used as a protective film for various substrates, as a base for coating and laminated films, undercoat films, and films for electronic devices that can be laminated on substrates. available It has been confirmed that these aluminum oxide film-attached substrates have minute irregularities on the surface of the film obtained by film formation, and can be used as an antireflection effect and as a catalyst carrier. In this way, the substrate with an aluminum oxide film of the present invention can be used as an aluminum oxide functional film.

[Example 3-2-8]

Glass substrates provided with the aluminum oxide film described in Examples 3-2-1, 2, 3 and 4, polypropylene (PP) and polyethylene terephthalate (PET) provided with the aluminum oxide film obtained in Example 3-2-6 ) can be used as a base material having an aluminum oxide functional film having the functions described in Example 3-2-7.

<Fourth aspect of the present invention>

The preparation of the alkyl aluminum compound-containing solution of the present invention was carried out under a nitrogen gas atmosphere, and all solvents were dehydrated and degassed before use.

<Number of moles of trialkyl aluminum>

It is the same as the first aspect of the present invention.

<Measurement of physical properties>

The average particle diameter (50% volume diameter) of the droplets formed using the spray nozzle of the present invention was measured using a laser beam scattering type particle size distribution analyzer (Nikkiso Co., Ltd. "spray particle size distribution analyzer CT Aerotruck LDSA) -3500A”) was used to measure droplets at a distance of 20 cm from the spray nozzle.

The aluminum oxide thin film produced by the production method of the present invention is obtained without ATR correction by the ATR (Attenuated Total Reflection) method using a ZnSe prism in an FT-IR spectrometer ("FT/IR-4100" manufactured by Nippon Bunko Co., Ltd.) Relative IR measurements were performed.

Originally, when using a ZnSe prism, it was difficult to measure a thin film having a refractive index exceeding 1.7, and considering that the refractive index of general aluminum oxide is 1.77, it was assumed that the measurement was difficult. However, surprisingly, measurements were possible. It was estimated that the refractive index of the aluminum oxide thin film according to the present invention was 1.7 or less.

In the aluminum oxide thin film prepared by the production method of the present invention, a portion of the film was cut with a knife, and the film thickness was measured using a stylus-type surface shape measuring device (DektakXT-S, manufactured by Bulgano Co., Ltd.).

The aluminum oxide thin film prepared by the production method of the present invention was measured for visible light vertical transmittance using a light source (DH-2000-BAL, manufactured by Ocean Photonics) and a spectrometer (USB-4000, manufactured by Ocean Photonics).

[Example 4-1]

To 18.0 g of tetrahydrofuran (hereinafter referred to as THF), 2.01 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at 25° C., and sufficiently stirred to obtain a 10% by mass triethyl aluminum THF solution (hereinafter referred to as solution A).

Spray coating was performed using the obtained solution A. In air at room temperature of 25°C and relative humidity of 43%, it was carried out using a two-fluid spray nozzle (micro-miniature vortex-type precise spray nozzle, manufactured by Atomax, Inc., AM4S-OSV-0.4, nozzle diameter 0.4 mm). The distance between the spray nozzle and the substrate (alkali-free glass, manufactured by Corning, EagleXG, 18 mm x 18 mm x 0.7 mmt) was set to 20 cm. Droplets of 3 to 30 μm were formed by mixing 2 ml/min of solution A and 8 NL/min of nitrogen gas in a spray nozzle. The average particle diameter (50% volume diameter) of the formed droplets was measured with a laser beam scattering type particle size distribution analyzer and found to be 8.5 µm. The formed droplets were sprayed onto a substrate heated to 200° C. for 8 minutes.

As a result of IR measurement of the thin film formed on the substrate by the ATR method, a spectrum as shown in FIG. 4B was obtained. A broad Al-O-Al vibration peak was confirmed from 550 to around 1500 cm ^-1 , and formation of an Al-O-Al bond was confirmed. Thus, formation of an aluminum oxide thin film was confirmed. Since there was no vibration peak of organic matter around 3000 cm ^-1 , it was confirmed that there was no remaining organic matter. The IR spectrum of the alkali-free glass itself by the ATR method is shown in FIG. 4a and is clearly different from FIG. 4b. The vertical transmittance of visible light at 550 nm was 97.5%, which was transparent, and the film thickness was 293 nm according to a stylus-type surface shape measuring device.

[Example 4-2]

To 18.01 g of diisopropyl ether, 2.00 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at 25° C., and sufficiently stirred to obtain a 10% by mass triethyl aluminum diisopropyl ether solution (hereinafter, solution B).

It was spray-coated to the same substrate as in Example 4-1 in the same manner and conditions as in Example 4-1, except that Solution B was used. The average particle diameter (50% volume diameter) of the formed droplets was measured with a laser beam scattering type particle size distribution analyzer and found to be 8.0 µm.

As a result of IR measurement of the thin film formed on the substrate by the ATR method, a spectrum as shown in FIG. 4c was obtained. As in Example 4-1, formation of an Al-O-Al bond was confirmed. Thus, formation of an aluminum oxide thin film was confirmed. Since there was no vibration peak of organic matter around 3000 cm ^-1 , it was confirmed that there was no remaining organic matter. The vertical transmittance of visible light at 550 nm was 98.0% and was transparent, and the film thickness was 277 nm according to a stylus-type surface shape measuring device.

[Example 4-3]

To 8.00 g of THF, 10.01 g of hexane and 2.01 g of triethylaluminum (manufactured by Tosoh FineChem Co., Ltd.) were added at 25°C, and sufficiently stirred to obtain a 10% by mass triethylaluminum diisopropyl ether solution (solution C below).

It was spray-coated to the same substrate as in Example 4-1 in the same manner and conditions as in Example 4-1, except that Solution C was used. The average particle diameter (50% volume diameter) of the formed droplets was measured with a laser beam scattering type particle size distribution analyzer and found to be 7.5 µm.

When the thin film formed on the substrate was subjected to IR measurement by the ATR method, formation of an Al-O-Al bond was confirmed as in Example 4-1. Thus, formation of an aluminum oxide thin film was confirmed.

[Example 4-4]

To 17.9 g of tetrahydrofuran (hereinafter referred to as THF), 2.01 g of triisobutylaluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at 25° C. and sufficiently stirred to obtain a 10% by mass triisobutylaluminum THF solution (hereinafter solution D).

It was spray-coated to the same substrate as in Example 4-1 in the same manner and conditions as in Example 4-1, except that Solution D was used. The average particle diameter (50% volume diameter) of the formed droplets was measured with a laser beam scattering type particle size distribution analyzer and found to be 8.0 µm.

As a result of IR measurement of the thin film formed on the substrate by the ATR method, a spectrum as shown in FIG. 4d was obtained. As in Example 4-1, formation of an Al-O-Al bond was confirmed. Thus, formation of an aluminum oxide thin film was confirmed. Since there was no vibration peak of organic matter around 3000 cm ^-1 , it was confirmed that there was no remaining organic matter. The vertical transmittance of visible light at 550 nm was 99.3%, which was transparent, and the film thickness was 130 nm according to a stylus-type surface shape measuring device.

[Comparative Example 4-1]

To 18.00 g of hexane, 2.00 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at 25°C, and sufficiently stirred to obtain a 10% by mass triethyl aluminum hexane solution (hereinafter, solution E).

It was spray-coated to the same substrate as in Example 4-1 in the same manner and conditions as in Example 4-1, except that Solution E was used. From the IR measurement by the ATR method, the vertical transmittance measurement, and the stylus-type surface shape measurement, the thin film was not formed and the thin film was not adhered.

[Comparative Example 4-2]

To 19.1 g of toluene, 1.01 g of aluminum isopropoxide (manufactured by Aldrich Co.) was added at 25°C and sufficiently stirred to obtain a 5% by mass aluminum isopropoxide toluene solution (hereinafter solution F).

It was spray-coated to the same substrate as in Example 4-1 in the same manner and conditions as in Example 4-1, except that Solution F was used. From the IR measurement by the ATR method, the vertical transmittance measurement, and the stylus-type surface shape measurement, the thin film was not formed and the thin film was not adhered.

[Comparative Example 4-3]

To 19.0 g of toluene, 1.00 g of aluminum acetylacetonate (manufactured by Aldrich) was added at 25° C., and sufficiently stirred to obtain a 5% by mass aluminum acetylacetonate toluene solution (hereinafter, solution G).

It was spray-coated to the same substrate as in Example 4-1 in the same manner and conditions as in Example 4-1, except that Solution G was used. From the IR measurement by the ATR method, vertical transmittance measurement, and stylus-type surface shape measurement, no thin film was formed, and the thin film was not adhered.

<Fifth aspect of the present invention>

The preparation of the alkyl aluminum compound-containing solution of the present invention was carried out under a nitrogen gas atmosphere, and all solvents were dehydrated and degassed before use.

<Number of moles of trialkyl aluminum>

It is the same as the first aspect of the present invention.

<Measurement of physical properties>

The average particle diameter (50% volume diameter) of the droplets formed using the spray nozzle of the present invention was measured using a laser beam scattering method particle size distribution measuring device ("spray particle diameter distribution measuring device CT Aerotrac LDSA-3500A" manufactured by Nikkiso Co., Ltd.) Thus, droplets at a distance of 20 cm from the spray nozzle were measured.

The film thickness and refractive index of the aluminum oxide thin film prepared by the production method of the present invention were measured using a high-speed spectroscopic ellipsometer (M-2000, manufactured by J.A. Uram Japan).

The effective carrier life time was measured using a lime time measuring instrument (WCT-120, manufactured by Sinton) by a quasi-steady-state photoconductivity method (QSSPC method). In addition, the effective carrier life time in the examples is a value at an excess carrier density of 10 ¹⁵ cm ^-3 .

Using the effective carrier lifetime value measured as described above, the surface recombination rate S was determined based on the following equation (1). In Formula (1), W represents a wafer thickness, τ _eff represents an effective lifetime, and τ _bulk represents a bulk lifetime. W was calculated as 300 μm and τ _bulk as ∞.

[Example 5-1]

To 18.1 g of tetrahydrofuran (hereinafter referred to as THF), 2.01 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at 25° C., and sufficiently stirred to obtain a 10% by mass triethyl aluminum THF solution (hereinafter referred to as solution A).

Spray coating was performed using the obtained solution A. In a nitrogen gas atmosphere, it was carried out using a two-fluid spray nozzle (ultra-small vortex-type precision spray nozzle, manufactured by Atomax, Inc., AM4S-OSV-0.4, nozzle diameter: 0.4 mm). Spray nozzle and substrate (p-type silicon substrate, manufactured by Topsil, PV-FZ (wafer thickness 255 to 305 μm, orientation <100>, volume resistivity 1 to 5 Ωcm), 4-inch disk divided into 4 equal parts, 5 After washing with hydrofluoric acid in weight %, the distance of use) was set to 20 cm. Droplets having an average particle diameter of 3 to 30 μm were formed by mixing 2 ml/min of solution A and 8 NL/min of nitrogen gas in a spray nozzle. The average particle diameter (50% volume diameter) of the formed droplets was measured with a laser beam scattering type particle size distribution analyzer and found to be 8.5 µm. At the same time, nitrogen gas containing water formed by introducing nitrogen gas at 10 NL/min into water heated to 65 DEG C was introduced into the vicinity of the substrate. The formed droplets were sprayed onto a substrate heated at 200° C. for 2 minutes in the presence of the above water. After that, the base material was changed to a complete nitrogen gas atmosphere, and then fired at 400°C for 5 minutes. The same treatment was performed on the back side as well.

It was 69 nm and 1.50 when the film thickness and refractive index of the thin film formed on the base material were measured using the high-speed spectroscopic ellipsometer. The effective lifetime was 606 μs, and the recombination rate was 24.8 cm/s.

[Example 5-2]

The film obtained in Example 5-1 was further baked at 400°C for 5 minutes in a forming gas atmosphere composed of 5 vol% of hydrogen and 95 vol% of nitrogen. The effective lifetime of the obtained film increased to 698 μs, and the recombination rate became 21.5 cm/s.

[Example 5-3]

To 18.1 g of diisopropyl ether, 2.00 g of triethyl aluminum (manufactured by Tosoh FineChem Co., Ltd.) was added at 25° C., and sufficiently stirred to obtain a 10% by mass triethyl aluminum diisopropyl ether solution (hereinafter, solution B).

Except for using solution B, spray coating and firing were carried out on the same substrate as in Example 5-1 under the same method and conditions as in Example 5-1. The average particle diameter (50% volume diameter) of the formed droplets was measured with a laser beam scattering type particle size distribution analyzer and found to be 8.0 µm.

The effective lifetime of the thin film formed on the substrate was 506 μs, and the recombination rate was 29.6 cm/s.

[Example 5-4]

The film obtained in Example 5-3 was further baked at 400°C for 5 minutes in a forming gas atmosphere composed of 5 vol% of hydrogen and 95 vol% of nitrogen. The effective lifetime of the obtained film increased to 821 μs, and the recombination rate became 18.3 cm/s.

The results so far are summarized in Table 5-1.

[Table 5-1]

The present inventions 1 to 5 are useful in the field of aluminum oxide film production. In particular, the present invention 1 is useful in the field of alkylating agents and reactive agents in organic synthesis and the like, and in the field of producing aluminum oxide thin films. The aluminum oxide thin film can provide heat dissipation, heat resistance, air and moisture barrier properties, antireflection, antistatic, antifogging, wear resistance, and the like.

The aluminum oxide thin film of the present invention 4 imparts heat dissipation, heat resistance, air and moisture barrier properties, antireflection effect, antistatic effect, antifogging effect, abrasion resistance, passivation, etc. Can be provided.

The aluminum oxide thin film of the present invention 5 can be provided to a passivation film, a solar cell device using the same, and the like.

2a and 3a
1: spray bottle 2: substrate holder (with heater)
3: atomizing nozzle 4: compressor
5: Substrate 6: Tube for water vapor introduction
5a and 5b
1: spray bottle 2: substrate holder (with heater)
3: atomizing nozzle 4: high-pressure nitrogen cylinder
5: substrate 6: water inlet
7: inert gas inlet 8: exhaust port
9: fence 11: silicon semiconductor substrate
12: n + layer 13: antireflection and passivation thin film
14: passivated thin film 15: grid electrode
16: aluminum electrode 17: Al-Si alloy layer
18: P ⁺ layer 100: solar cell element

Claims (69)

An alkyl aluminum compound composed of dialkyl aluminum, trialkyl aluminum, or a mixture thereof (provided that the alkyl group has 1 to 6 carbon atoms and may be the same or different) and a solvent, and the content of the alkyl aluminum compound is 15% by mass or more , as a solution containing an alkyl aluminum compound,
The solvent is an organic compound having a boiling point of 160° C. or higher, an amide structure represented by the following general formula (4), and a cyclic structure (hereinafter referred to as “cyclic amide compound”),
A solution containing an alkyl aluminum compound containing the cyclic amide compound in an amount greater than 2.6 in a molar ratio relative to the alkyl aluminum compound:

. The method of claim 1, wherein the cyclic amide compound is N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3-dimethyl-3,4,5,6- A solution containing an alkyl aluminum compound, which is tetrahydro-2(1H)-pyrimidinone or a mixture thereof. The method according to any one of claims 1 to 2, wherein the dialkyl aluminum, the trialkyl aluminum, or the dialkyl aluminum and trialkyl aluminum are alkyl aluminum compounds represented by the following general formula (1) or (2) , a solution containing an alkyl aluminum compound:

(In the formula, R ¹ represents a methyl group or an ethyl group, and R ² represents a halogen, a methyl group or an ethyl group.)

(In the formula, R ³ represents an isobutyl group, and R ⁴ represents a halogen or isobutyl group.)
The solution containing an alkyl aluminum compound according to claim 3, wherein the alkyl aluminum compound represented by the general formula (1) is triethyl aluminum or trimethyl aluminum.
The solution containing an alkyl aluminum compound according to claim 3, wherein the alkyl aluminum compound represented by the general formula (2) is triisobutylaluminum.
The alkyl aluminum compound-containing solution according to claim 5, which contains 30% by mass or more of the compound represented by the general formula (2).
The solution containing an alkyl aluminum compound according to any one of claims 1 to 2, further comprising a solvent other than the cyclic amide compound.
A solution containing an alkyl aluminum partial hydrolyzate containing a partial hydrolyzate of an alkyl aluminum compound (provided that the alkyl group has 1 to 6 carbon atoms and may be the same or different) composed of dialkyl aluminum, trialkyl aluminum or a mixture thereof and a solvent As,
The solvent is an organic compound having a boiling point of 160° C. or higher, an amide structure represented by the following general formula (4), and a cyclic structure (hereinafter referred to as “cyclic amide compound”),
The partial hydrolyzate is hydrolyzed with water in a molar ratio of 0.5 to 1.3 with respect to aluminum in the alkyl aluminum compound, a solution containing an alkyl aluminum partial hydrolyzate:

. The solution containing an alkyl aluminum partial hydrolyzate according to claim 8, which contains one or more of the cyclic amide compounds in a molar ratio with respect to aluminum in the alkyl aluminum compound.
The method of claim 8 or 9, wherein the cyclic amide compound is N-methyl-2-pyrrolidone, or 1,3-dimethyl-imidazolidinone, 1,3-dimethyl-3,4, A solution containing an alkyl aluminum partial hydrolyzate, which is 5,6-tetrahydro-2(1H)-pyrimidinone or a mixture thereof.
The alkyl aluminum compound according to any one of claims 8 to 9, wherein the dialkyl aluminum, the trialkyl aluminum, or the dialkyl aluminum and trialkyl aluminum are represented by the following general formula (1) or (2) Solutions containing phosphorus, alkyl aluminum partial hydrolysates:

(In the formula, R ¹ represents a methyl group or an ethyl group, and R ² represents a halogen, a methyl group or an ethyl group.)

(In the formula, R ³ represents an isobutyl group, and R ⁴ represents a halogen or isobutyl group.) The solution containing an alkyl aluminum partial hydrolyzate according to any one of claims 8 to 9, wherein the trialkyl aluminum is an alkyl aluminum compound represented by the following general formula (3):

(In the formula, R ⁵ represents a methyl group, an ethyl group or an isobutyl group.) The solution containing an alkyl aluminum partial hydrolyzate according to any one of claims 8 to 9, further comprising a solvent other than the cyclic amide compound.
A method for producing an aluminum oxide thin film, comprising applying the solution containing an alkyl aluminum partial hydrolyzate according to any one of claims 8 to 9 to a substrate to obtain an aluminum oxide thin film.
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