JP2007291334A - Polyamideimide resin, polyamideimide resin composition, coating, coating for inside surface of can or tube, and can or tube using the coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyamideimide resin capable of forming a coating having high processability, adhesion and solvent resistance. <P>SOLUTION: The polyamideimide resin is obtained by polymerizing (1) an aromatic amine component consisting of an aromatic diamine compound and/or an aromatic diisocyanate compound, (2) an aromatic acid component selected from the group consisting of aromatic dicarboxylic acid compounds, aromatic diol compounds, aromatic tribasic acid anhydrides, aromatic tribasic acid anhydride monochlorides and aromatic tetrabasic acid dianhydrides and (3) a copolymerizable component having an aliphatic structure and being copolymerizable with an aromatic amine or acid component, and has an aliphatic structure incorporated in an aromatic polyamideimide resin structure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polyamide-imide resin, a polyamide-imide resin composition, a paint comprising the polyamide-imide resin or the polyamide-imide resin composition as a coating film component, a can or tube using the polyamide-imide resin, the polyamide-imide resin composition, or the paint. The present invention relates to a coating for inner surface coating and a can or tube using the coating.

  Polyamideimide resin has many excellent properties such as high insulation, high heat resistance, high strength, high wear resistance, and high solvent resistance, and also has an amide bond in the resin skeleton and an acid group at the end of the resin. Is widely used as an excellent protective coating material for various substrate surfaces such as metal and glass in various applications in various industrial fields because it forms hydrogen bonds with various substrate surfaces and exhibits excellent adhesion. .

  Since the adhesion of the polyamide-imide resin is particularly excellent for aluminum, it is often used as a protective coating material on the surface of aluminum products, combined with the excellent solvent resistance of the polyamide-imide resin, cosmetics, pharmaceuticals, It has long been used as an inner coating material for aluminum cans and tubes for food and chemical products.

A general method for producing a polyamide-imide resin is known (for example, see Patent Document 1). Conventional polyamide-imide resins use diphenylmethane diisocyanate and trimellitic anhydride as materials, and a large amount of polyamide-imide resin is used. It is produced by an industrially superior isocyanate method that can be produced continuously and inexpensively.
Japanese Patent Publication No. 44-19274

  In recent years, demand for polyamide-imide resin has been increasing, particularly as an inner coating material for aerosol cans. This is because LP gas (LPG, LPG, etc.) is used as a new propellant in place of the chlorofluorocarbons that have been used in the past due to the “Law Concerning Protection of the Ozone Layer by Regulations on Specific Substances (Ozone Layer Protection Act)” enforced in 1988. Liquefied petroleum gas) and dimethyl ether (DME) have come to be used, but epoxy and phenolic coatings that have been the mainstream coating material for aerosol cans in the past have been corroded by DME. Higher polyamideimide resins have been used.

  Currently, there is a growing market need to process various types of aluminum cans and tubes for cosmetics, pharmaceuticals, foods, chemical products, etc., including this aerosol can, but conventional diphenylmethane diisocyanate and trimellitic anhydride In the polyamideimide resin coating made of the above, due to lack of workability and adhesion, the coating cannot follow the deformation of the base material during processing, and various defects such as peeling, peeling and cracking occur.

  As a countermeasure against this, there is a strong demand for the development of polyamide-imide resins that can form coatings with high workability, high adhesion, and high solvent resistance, but high workability that can withstand processing into various shapes. Polyamideimide resins having high adhesion and high solvent resistance have not been put into practical use until now.

  The object of the present invention is for aerosol cans, aluminum cans or tubes that are processed into various shapes, for inner surface coating, for a wide variety of applications that require high workability, high adhesion, and high solvent resistance. A polyamide-imide resin capable of forming a coating having high processability, high adhesion and high solvent resistance, a polyamide-imide resin composition, a paint comprising the polyamide-imide resin or the polyamide-imide resin composition as a coating film component, An object of the present invention is to provide a can or tube inner surface coating material using this polyamideimide resin, a polyamideimide resin composition or a coating material, and a can or tube using this coating material.

  As a result of studying a polyamide-imide resin composition capable of forming a coating having the above-described high workability, high adhesion, and high solvent resistance, the present inventors have determined that a specific aliphatic structure is an aromatic polyamide-imide resin structure. By introducing it into the present invention, it has been found that processability and adhesion are dramatically improved compared to a coating made of a conventional polyamideimide resin, and that the solvent resistance can be maintained. It came to be completed.

  That is, the present invention comprises (1) an aromatic amine component composed of an aromatic diamine compound and / or an aromatic diisocyanate compound, and (2) an aromatic dicarboxylic acid compound, an aromatic diol compound, an aromatic compound in a basic polar solvent. An aromatic acid component selected from the group consisting of an aromatic tribasic acid anhydride, an aromatic tribasic acid anhydride monochloride and an aromatic tetrabasic acid dianhydride; and (3) an aromatic amine having an aliphatic structure The present invention relates to a polyamideimide resin obtained by polymerizing a component or a copolymerizable component that can be copolymerized with an aromatic acid component, wherein an aliphatic structure is introduced into the aromatic polyamideimide resin structure.

  The present invention also relates to the above polyamideimide resin, wherein the aliphatic structure has a carbonate bond.

  In the present invention, the copolymerization component comprises (3-1) an aliphatic amine component comprising an aliphatic diamine compound and / or an aliphatic diisocyanate compound, and (3-2) an aliphatic dicarboxylic acid compound, an aliphatic diol. It is at least one selected from the group consisting of an aliphatic acid component selected from the group consisting of a compound, an aliphatic tribasic acid anhydride, an aliphatic tribasic acid monochloride and an aliphatic tetrabasic acid dianhydride. It relates to the above-mentioned polyamide-imide resin.

  The present invention also relates to the above polyamideimide resin, wherein the copolymer component comprises at least an aliphatic polycarbonate diol or a derivative thereof.

（式中、複数個のＲは、それぞれ独立に炭素数１〜１８のアルキレン基を示し、複数個のＸは、それぞれ独立に炭素数１〜１８のアルキレン基又はアリーレン基を示し、ｍ及びｎは、それぞれ独立に１〜２０の整数を示し、Ｙは三価の脂肪族基又は芳香族基を示し、少なくとも１個のＸ及び／又はＹは芳香族基を示す。）
で表される繰り返し単位を含有してなることを特徴とする前記のポリアミドイミド樹脂に関する。 In the present invention, the polyamideimide resin has the following general formula (I):

(In the formula, a plurality of R's each independently represents an alkylene group having 1 to 18 carbon atoms, a plurality of X's each independently represents an alkylene group or arylene group having 1 to 18 carbon atoms, m and n Each independently represents an integer of 1 to 20, Y represents a trivalent aliphatic group or aromatic group, and at least one X and / or Y represents an aromatic group.)
The above-mentioned polyamide-imide resin is characterized by comprising a repeating unit represented by:

  The present invention also relates to a polyamideimide resin composition comprising 1 to 100 parts by weight of one or more curing agents with respect to 100 parts by weight of the polyamideimide resin.

  The present invention also relates to the above-mentioned polyamideimide resin composition, wherein the curing agent is a polyfunctional epoxy compound.

  Moreover, this invention relates to the coating material which contains the said polyamidoimide resin or the said polyamidoimide resin composition as a coating-film component.

  Moreover, this invention relates to the coating material for can inner surface coatings which uses the said polyamidoimide resin, the said polyamidoimide resin composition, or the said coating material.

  The present invention also relates to the above-mentioned paint for coating the inner surface of the can, wherein the can is made of aluminum.

  The present invention also relates to the above-mentioned paint for coating an inner surface of a can, wherein the can is an aerosol can.

  Moreover, this invention relates to the can tube which formed the coating film on the inner surface using the said coating material for can inner surface coatings.

  Moreover, this invention relates to the coating material for tube inner surface coatings which uses the said polyamide-imide resin, the said polyamide-imide resin composition, or the said coating material.

  The present invention also relates to the above-mentioned paint for coating an inner surface of a tube, wherein the tube is made of aluminum.

  Moreover, this invention relates to the tube which formed the coating film on the inner surface using the said coating material for tube inner surface coating.

  By using the polyamideimide resin of the present invention, workability and adhesion are dramatically improved and solvent resistance compared to a coating obtained from a polyamideimide resin comprising conventional diphenylmethane diisocyanate and trimellitic anhydride. It is possible to form a coating that can hold These are aerosol cans and other cans that are processed into various shapes, especially aluminum cans or tube inner coatings and cans or tubes that require high workability, high adhesion and high solvent resistance. It can have tremendous benefits for a wide variety of applications.

  The polyamideimide resin of the present invention comprises (1) an aromatic amine component comprising an aromatic diamine compound and / or an aromatic diisocyanate compound, and (2) an aromatic dicarboxylic acid compound, an aromatic diol compound in a basic polar solvent. An aromatic acid component selected from the group consisting of aromatic tribasic acid anhydrides, aromatic tribasic acid anhydride monochlorides and aromatic tetrabasic acid dianhydrides; and (3) having an aliphatic structure and aromatic A polyamideimide resin obtained by polymerizing a copolymerizable component that can be copolymerized with an aromatic amine component or an aromatic acid component, wherein an aliphatic structure is introduced into the aromatic polyamideimide resin structure.

  Examples of the copolymer component include an aliphatic amine component composed of an aliphatic diamine compound and / or an aliphatic diisocyanate compound, an aliphatic dicarboxylic acid compound, an aliphatic diol compound, an aliphatic tribasic acid anhydride, and an aliphatic three component. Examples thereof include an aliphatic acid component selected from the group consisting of a basic acid anhydride monochloride and an aliphatic tetrabasic acid dianhydride. These copolymerization components may be used alone or in combination of two or more.

  The typical compounds used in the above production method are listed below.

  First, examples of the aromatic diamine compound include tolidine, dihydroxybenzidine, dianisidine, diaminodiphenylmethane, dimethyldiaminodiphenylmethane, diaminodiethyldiphenylmethane, diaminodiphenyl ether, diaminodiphenylsulfone, phenylenediamine, xylylenediamine, toluenediamine, and bis (trifluoro). Methyl) diaminodiphenyl, tolidinesulfone, diaminobenzophenone, thiodianiline, sulfonyldianiline, diaminobenzanilide, bis (aminophenoxy) benzene, bis (aminophenoxy) biphenyl, bis (aminophenoxyphenyl) propane, bis [(aminophenoxy) phenyl Sulfone, bis [(aminophenoxy) phenyl] hexafluoropropane Bis (aminopropyl) tetramethyl disiloxane, diaminobenzidine, and the like.

  Examples of the aliphatic diamine compound include polymethylene diamine having 1 to 18 carbon atoms such as hexamethylene diamine.

  Examples of the aromatic diisocyanate compound include naphthalene diisocyanate, tolidine diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, tolylene diisocyanate, and xylylene diisocyanate.

  Examples of the aliphatic diisocyanate compound include polymethylene diisocyanate having a polymethylene group having 1 to 18 carbon atoms such as hexamethylene diisocyanate.

  Examples of the aromatic dicarboxylic acid compound include naphthalenedicarboxylic acid, isophthalic acid, terephthalic acid, and the like.

  Examples of the aliphatic dicarboxylic acid compound include sebacic acid, adipic acid, malonic acid, succinic acid, glutaric acid, brassic acid, oxalic acid (anhydride), itaconic acid, dodecanedioic acid, and 3,3′-dithiodipropion. Acid, 3,3'-thiodipropionic acid, etc. are mentioned.

  Examples of aromatic diol compounds include derivatives of aromatic polycarbonate diols such as resorcinol, hydroquinone, biphenyldiol, bisphenol A, naphthalene diol, aromatic polycarbonate diol, and aromatic polycarbonate diol-chloroformate diester.

  Examples of the aliphatic diol compound include derivatives of aliphatic polycarbonate diols such as ethylene glycol, 1,4-butanediol, 1,6-hexanediol, aliphatic polycarbonate diol, and aliphatic polycarbonate diol-chloroformate diester. Can be mentioned.

  Examples of the aromatic tribasic acid anhydride and the aromatic tribasic acid anhydride monochloride include trimellitic anhydride and trimellitic anhydride chloride.

  Examples of the aliphatic tribasic acid anhydride and the aliphatic tribasic acid anhydride monochloride include anhydrous citric acid and anhydrous citric acid monochloride.

  Examples of aromatic tetrabasic acid dianhydrides include biphenyl tetracarboxylic dianhydride, pyromellitic anhydride, oxydiphthalic dianhydride, benzophenone tetracarboxylic dianhydride, diphenyl sulfone tetracarboxylic dianhydride, ( Hexafluoroisopropylidene) diphthalic dianhydride, terphenyl tetracarboxylic dianhydride and the like.

  In addition to the above compounds, hydroxynaphthoic acid, oxynaphthoic acid, hydroxybiphenylcarboxylic acid, 1,2-aminododecanoic acid, trimethylolethane, trimethylolpropane, gluconic acid, lactic acid, fumaric acid, DL-malic acid, xylitol, D-sorbitol, DL-alanine and the like may be used.

  It should be noted that aromatic and aliphatic diamine compounds, aromatic and aliphatic diisocyanate compounds, aromatic and aliphatic dicarboxylic acid compounds, aromatic and aliphatic diol compounds, aromatic and Aliphatic tribasic acid anhydrides, aromatic and aliphatic tribasic acid anhydride monochlorides, and aromatic and aliphatic tetrabasic acid dianhydrides are not limited to the above compounds, but are aromatics that are the main skeleton It goes without saying that a wide variety of compounds can be used to form structures and to introduce aliphatic structures to improve processability.

  The polyamide-imide resin of the present invention dramatically improves processability and adhesion compared to conventional polyamide-imide resins composed of diphenylmethane diisocyanate and trimellitic anhydride by introducing an aliphatic structure, and is solvent resistant. Any of the above compounds may be used in producing this polyamideimide resin, but an aliphatic structure containing a carbonate bond is introduced in order to improve processability and adhesion. It is preferable.

In order to introduce an aliphatic structure containing a carbonate bond, it is more preferable to copolymerize at least one monomer selected from the group consisting of aliphatic polycarbonate diols or derivatives thereof.
Furthermore, in order to improve processability and adhesion and to maintain solvent resistance, the polyamideimide resin is represented by the following general formula (II):

（式中、複数個のＲは、それぞれ独立に炭素数１〜１８のアルキレン基を示し、複数個のＸは、それぞれ独立に炭素数１〜１８のアルキレン基又はアリーレン基を示し、ｍ及びｎは、それぞれ独立に１〜２０の整数を示し、Ｙは三価の脂肪族基又は芳香族基、好ましくは芳香族基を示し、少なくとも１個のＸ及び／又はＹは芳香族基を示す。）
で表される繰り返し単位を含有してなることがより好ましい。

(In the formula, a plurality of R's each independently represents an alkylene group having 1 to 18 carbon atoms, a plurality of X's each independently represents an alkylene group or arylene group having 1 to 18 carbon atoms, and m and n Each independently represents an integer of 1 to 20, Y represents a trivalent aliphatic group or aromatic group, preferably an aromatic group, and at least one X and / or Y represents an aromatic group. )
It is more preferable to contain the repeating unit represented by these.

  The blending amount of the aliphatic polycarbonate diol or derivative thereof used for introducing the repeating unit represented by the above general formula (II) is not particularly limited, but processability, improved adhesion, and solvent resistance. In order to maintain the above, it is preferable that the polyamideimide resin is polymerized containing 1 to 50 mol% of an aliphatic polycarbonate diol or a derivative thereof in the total acid component of the raw material.

  If the amount of the aliphatic polycarbonate diol or its derivative is less than 1 mol%, the processability and adhesion tend to be insufficient as compared with the conventional polyamideimide resin, and if it exceeds 50 mol%, the solvent resistance is increased. Tend to decrease. In order to improve workability and adhesion and to maintain solvent resistance, the amount of aliphatic polycarbonate diol or a derivative thereof is more preferably 5 to 30 mol%.

  Further, in the total amount of the aromatic amine component, the aromatic acid component and the polymerization component having an aliphatic structure used for the polymerization, the amount of the polymerization component having an aliphatic structure is preferably 0.5 to 50 mol%. 2 to 40 mol% is more preferable.

  Examples of aliphatic polycarbonate diols that can be used for polymerizing the polyamideimide resin according to the present invention include, for example, trade names PLACEL CD-205, 205PL, 205HL, 210, 210PL, 210HL, and 220 manufactured by Daicel Chemical Industries, Ltd. , 220PL, and 220HL are listed, and these can be used alone or in combination of two or more.

  The compounding amount of the amine component (the sum of the aromatic amine component and the aliphatic amine component) and the acid component (the sum of the aromatic acid component and the aliphatic amine component) is the viewpoint of the molecular weight and the degree of crosslinking of the polyamideimide resin produced. Therefore, the amine component is preferably 0.8 to 1.2 mol, more preferably 0.95 to 1.1 mol, with respect to 1.0 mol of the total amount of the acid component.

  N-methyl-2-pyrrolidone, γ-butyrolactone, dimethylacetamide, dimethylformamide and the like can be used as the basic polar solvent used for polymerization of the polyamideimide resin according to the present invention. In order to carry out in a short time, it is preferable to use a high boiling point solvent such as N-methyl-2-pyrrolidone.

Moreover, although there is no restriction | limiting in the usage-amount of a solvent, It is preferable to set it as 50-500 weight part with respect to 100 weight part of total amounts of an isocyanate component or an amine component, and an acid component.
The conditions for synthesizing the polyamide-imide resin are various and cannot be specified in general, but it is usually carried out at a temperature of 120 to 155 ° C. and is preferably carried out in an atmosphere such as nitrogen in order to reduce the influence of moisture in the air. .

  The polyamideimide resin according to the present invention preferably has a number average molecular weight of 5,000 to 50,000. When the number average molecular weight is less than 5,000, the solvent resistance of the coating film tends to decrease when it is used as a coating film. When the number average molecular weight exceeds 50,000, the viscosity when dissolved in a solvent at an appropriate concentration as a paint is obtained. It tends to be high and the workability during painting tends to be inferior. For this reason, the number average molecular weight of the polyamideimide resin is more preferably 10,000 to 30,000.

  The number average molecular weight of the polyamideimide resin is sampled at the time of resin synthesis, measured by a gel permeation chromatograph (GPC) using a standard polystyrene calibration curve, and synthesized until the target number average molecular weight is reached. By continuing, it is managed within the above range.

  The polyamideimide resin thus obtained is diluted to an appropriate concentration as needed when used. As a diluting solvent, in addition to polar solvents such as N-methyl-2-pyrrolidone, γ-butyrolactone, dimethylformamide, dimethylacetamide, xylene, dimethyl sulfoxide, as cosolvents, polyols and their lower alkyl etherified products An acetylated product or the like may be used.

  For example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, glycerin, trimethylolpropane, isopropyl alcohol or their monomethyl etherified products, monoethyl ether, monoisopropyl etherified products, monobutyl etherified products, dimethyl etherified products and their monoacetyls Chemicals are used.

  The polyamideimide resin according to the present invention is usually a polyfunctional epoxy compound, an isocyanate compound, an amine compound for the purpose of accelerating the polymerization reaction and crosslinking reaction between the resins during heat curing in order to obtain sufficient solvent resistance. It is preferable to blend a curing agent such as a melamine compound or a polyester compound and use it as a polyamide-imide resin composition.

  As the curing agent, combined use of a polyfunctional epoxy compound is particularly preferred from the viewpoint of reactivity with the polyamideimide resin according to the present invention and the obtained coating film characteristics. The polyfunctional epoxy compound is not particularly limited, such as bisphenol A type, bisphenol F type, novolac type, amine type, alcohol type, biphenyl type, ester type, and a plurality of them can be used simultaneously.

  The blending amount of the curing agent such as the polyfunctional epoxy compound is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the polyamideimide resin. When the amount of the curing agent is less than 1 part by weight, there is a tendency that the effect of promoting the polymerization reaction and the crosslinking reaction is not sufficiently obtained, and when it exceeds 100 parts by weight, the solvent resistance of the resulting coating film tends to be lowered. . Therefore, the blending amount of the curing agent such as the polyfunctional epoxy compound is more preferably 10 to 60 parts by weight.

  The paint containing the polyamide-imide resin or polyamide-imide resin composition of the present invention as a coating film component is usually added to the above-mentioned solvent, and if necessary, thixotropic agent, pigment, filler, curing accelerator, polymerization Inhibitors, etc. can be blended. Examples of the thixotropic agent include fine particle silica, organic bentonite, and organic polymer fine particles. Examples of the pigment and filler include iron oxide, titanium oxide, aluminum oxide, barium sulfate, calcium carbonate, magnesium carbonate, talc, and clay silica.

  The polyamide-imide resin, the polyamide-imide resin composition, and the paint comprising the polyamide-imide resin composition as a coating film component are applied to the object to be coated and cured to form a film on the surface of the object to be coated. In particular, the polyamide-imide resin composition according to the present invention can form a flexible coating film having remarkably superior processability and adhesion as compared with conventional polyamide-imide resins, and retains solvent resistance. Therefore, it has great benefits in a wide variety of applications that require high workability, high adhesion, and high solvent resistance, and is processed into various shapes, especially aerosol cans. It has great benefits as a paint for the inner coating material of aluminum cans or tubes.

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples, and it goes without saying that many other embodiments based on the gist of the invention are included.
Example 1
4,4'-diphenylmethane diisocyanate as an amine component 1.0 mol, trimellitic anhydride 0.8 mol as an acid component, aliphatic polycarbonate diol (manufactured by Daicel Chemical Industries, Ltd., trade name PLACEL CD-220) 0.20 mol And N-methyl-2-pyrrolidone as a synthesis solvent (the amount of N-methyl-2-pyrrolidone used was 300 parts by weight with respect to 100 parts by weight of the total amount of isocyanate component and acid component), thermometer and cooling pipe The mixture was placed in the equipped flask and gradually heated over 2 hours with stirring in a dried nitrogen stream to 130 ° C.

  The temperature was maintained at 130 ° C. while paying attention to the sudden foaming of carbon dioxide gas generated by the reaction, and heating was continued for 8 hours, and the reaction was stopped to obtain a polyamideimide resin solution (number average molecular weight of polyamideimide resin: 25000). 25 parts by weight of an amine-type epoxy compound (trade name: Epicoat 604, manufactured by Japan Epoxy Resin Co., Ltd.) was added to 100 parts by weight of the polyamide resin.

Example 2
As an amine component, 0.2 mol of o-tolidine diisocyanate, 0.8 mol of 4,4'-diphenylmethane diisocyanate, as an acid component, 0.5 mol of trimellitic anhydride, 0.4 mol of sebacic acid, aliphatic polycarbonate diol (Daicel Chemical) Co., Ltd., trade name PLACEL CD-220PL) 0.1 mol and N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone used as a synthesis solvent) is used in a total amount of 100 parts by weight of isocyanate component and acid component. 300 parts by weight) was placed in a flask equipped with a thermometer and a cooling tube, and gradually heated to 130 ° C. over 2 hours with stirring in a dried nitrogen stream.

  Keeping the temperature at 130 ° C. while paying attention to the sudden foaming of carbon dioxide gas generated by the reaction, heating was continued for 6 hours and the reaction was stopped, and a polyamideimide resin solution (polyamideimide resin number average molecular weight: 22000) was obtained. Obtained. To this polyamideimide resin solution, 35 parts by weight of a bisphenol A type epoxy compound (trade name: Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) was added with respect to 100 parts by weight of the polyamide resin.

Example 3
1,6-hexane diisocyanate 0.3 mol, 4,4'-diphenylmethane diisocyanate 0.7 mol as isocyanate component, biphenyl-3,4,3 ', 4'-tetracarboxylic acid 0.2 mol as acid component and anhydrous Trimellitic acid 0.6 mol, polycarbonate diol (manufactured by Daicel Chemical Industries, Ltd., trade name PLACEL CD-220) 0.2 mol and use of N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone as a synthesis solvent) The amount was set to 300 parts by weight with respect to 100 parts by weight of the total amount of the isocyanate component and the acid component), and was gradually put in a flask equipped with a thermometer and a cooling tube over 2 hours while stirring in a dried nitrogen stream. The temperature was raised to 130 ° C.

  The temperature was kept at 130 ° C. while paying attention to the sudden foaming of carbon dioxide gas generated by the reaction, and the reaction was stopped after heating for 7 hours as it was, and a polyamideimide resin solution (polyamideimide resin number average molecular weight: 19000) was Obtained. To this polyamideimide resin solution, 35 parts by weight of a bisphenol A type epoxy compound (trade name: Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) was added with respect to 100 parts by weight of the polyamide resin.

Comparative Example 1
1.0 mol of 4,4'-diphenylmethane diisocyanate as the isocyanate component, 1.0 mol of trimellitic anhydride as the acid component, and N-methyl-2-pyrrolidone as the synthesis solvent (the amount of N-methyl-2-pyrrolidone used is isocyanate) 300 parts by weight with respect to 100 parts by weight of the total amount of the component and the acid component) was put in a flask equipped with a thermometer and a cooling tube, and gradually heated over 2 hours while stirring in a dried nitrogen stream And increased to 130 ° C.

  Keeping the temperature at 130 ° C. while paying attention to the sudden foaming of carbon dioxide gas generated by the reaction, the heating was continued for 8 hours, the reaction was stopped, and a polyamideimide resin solution (polyamideimide resin number average molecular weight: 25000) was Obtained. 25 parts by weight of an amine-type epoxy compound (trade name: Epicoat 604, manufactured by Japan Epoxy Resin Co., Ltd.) was added to 100 parts by weight of the polyamide resin.

(Test example)
Polyamideimide films were prepared from the polyamideimide resin composition solutions obtained in Examples 1, 2, 3 and Comparative Example 1 above, respectively, and were cured and adhesive after being extruded 5 mm with an Erichsen tester. A comparative test on sex was conducted. The test results are shown in Table 1.

1) Measure the rate of decrease in coating weight after sonication in N, N-dimethylformamide for 1 hour at room temperature.
2) Based on old JIS K 5400 (%, crosscut remaining rate), the remaining rate after tape peeling 5 times after crosscutting.
Each measurement is performed twice on a substrate with N = 2, and a total of four measured values are shown as ranges.
(100 indicates all data was 100, 0 indicates all data was 0).
3) Extruded by Eriksen testing machine.

4) T vent method. Coating and curing on an aluminum substrate of t = 0.5 mm, and confirming the occurrence of peeling, peeling and cracking of the coating film when the aluminum substrate of T = 0.5 mm is sandwiched and bent.
5) Even if the aluminum substrate is not sandwiched between the two, the film is not peeled off, peeled off or cracked.
6) When two aluminum substrates were sandwiched between them and bent, the coating film was cracked and creased. With three sheets, peeling, peeling and cracking of the coating did not occur.
Table 2 shows the conditions for producing the polyamideimide film.

  As shown in Table 1, the polyamideimide films prepared from the polyamideimide resin composition solutions obtained in Examples 1, 2, and 3 were obtained from the conventional polyamideimide resin composition solution obtained in Comparative Example 1. Compared to the produced polyamideimide film, the workability and adhesion are dramatically improved, and it is clear that the solvent resistance is maintained.

  In addition, the polyamideimide resin composition according to the present invention and the coating material comprising the polyamideimide resin composition as a coating film component have dramatically superior processability compared to conventional polyamideimide resins represented by comparative examples. It is clear that a flexible coating film having adhesiveness is formed and the solvent resistance is maintained. As a result, it has tremendous benefits in a wide variety of applications that require high workability, high adhesion, and high solvent resistance. Especially aluminum cans that are processed into various shapes including aerosol cans. Or it is clear that it has great utility as a paint for the inner surface coating material of the tube.

Claims (15)

  In a basic polar solvent, (1) an aromatic amine component comprising an aromatic diamine compound and / or an aromatic diisocyanate compound, and (2) an aromatic dicarboxylic acid compound, an aromatic diol compound, an aromatic tribasic acid anhydride An aromatic acid component selected from the group consisting of an aromatic tribasic acid anhydride monochloride and an aromatic tetrabasic acid dianhydride; and (3) an aliphatic amine component or an aromatic acid component having an aliphatic structure. A polyamideimide resin obtained by polymerizing a copolymerizable component that can be copolymerized with a polyamideimide resin in which an aliphatic structure is introduced into an aromatic polyamideimide resin structure.   The polyamideimide resin according to claim 1, wherein the aliphatic structure has a carbonate bond.   The copolymerization component is (3-1) an aliphatic amine component comprising an aliphatic diamine compound and / or an aliphatic diisocyanate compound, and (3-2) an aliphatic dicarboxylic acid compound, an aliphatic diol compound, an aliphatic tribase. The at least one selected from the group consisting of an aliphatic acid component selected from the group consisting of an acid anhydride, an aliphatic tribasic acid monochloride, and an aliphatic tetrabasic acid dianhydride. The polyamide-imide resin according to 1 or 2.   The polyamideimide resin according to any one of claims 1 to 3, wherein the copolymer component comprises at least an aliphatic polycarbonate diol or a derivative thereof. Polyamideimide resin is represented by the following general formula (I)

(In the formula, a plurality of R's each independently represents an alkylene group having 1 to 18 carbon atoms, a plurality of X's each independently represents an alkylene group or arylene group having 1 to 18 carbon atoms, and m and n Each independently represents an integer of 1 to 20, Y represents a trivalent aliphatic group or aromatic group, and at least one X and / or Y represents an aromatic group.)
The polyamidoimide resin in any one of Claims 1-4 characterized by containing the repeating unit represented by these.   A polyamideimide resin composition comprising 1 to 100 parts by weight of one or more curing agents with respect to 100 parts by weight of the polyamideimide resin according to claim 1.   The polyamideimide resin composition according to claim 6, wherein the curing agent is a polyfunctional epoxy compound.   The coating material which contains the polyamide-imide resin in any one of Claims 1-5, or the polyamide-imide resin composition of Claim 6 or 7 as a coating-film component.   A paint for coating the inner surface of a can using the polyamideimide resin according to any one of claims 1 to 5, the polyamideimide resin composition according to claim 6 or 7, or the paint according to claim 8.   The paint for coating the inner surface of a can according to claim 9, wherein the can or the product is made of aluminum.   The paint for coating the inner surface of a can according to claim 9 or 10, wherein the can is an aerosol can.   The can which formed the coating film in the inner surface using the coating material for can inner surface coating of Claim 9, 10 or 11.   A coating for coating the inner surface of a tube using the polyamide-imide resin according to any one of claims 1 to 5, the polyamide-imide resin composition according to claim 6 or 7, or the coating according to claim 8.   The tube inner surface coating material according to claim 13, wherein the tube is made of aluminum.   The tube which formed the coating film in the inner surface using the coating material for tube inner surface coating of Claim 13 or 14.