JP2009249567A - Heat resistant resin composition and coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat resistant resin composition that is reduced in the content of an organic solvent, does not cause environmental pollution or aggravation of working environment, is advantageous to safety and sanitation, and has an excellent adhesiveness to tin plate substrates even when exposed to an elevated temperature, and to provide a coating comprised of the same as a paint component. <P>SOLUTION: The heat resistant resin composition comprises (A) a polyamide resin obtained by reaction of a diisocyanate compound or diamine compound with a tribasic acid anhydride or tribasic acid anhydride chloride, (B) a basic compound, (C) water, and (D) tin acetylacetonate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat resistant resin composition and a paint.

Aqueous resin solutions that use water as a medium instead of organic solvents in terms of environmental protection, safety and health, economy, and painting workability have attracted attention, and polyamides that act on carboxyl groups remaining at the resin ends and basic compounds A method for water-solubilizing an imide resin has been reported (for example, JP-A No. 2002-284993). However, since the water-soluble polyamide-imide resin produced by the above method has a low adhesion to the tin substrate when exposed to high temperatures, improvement of this point is strongly desired.
JP 2002-284993 A

  The object of the present invention is to reduce the organic solvent content, to prevent environmental pollution and work environment deterioration, is advantageous for health and safety, and has excellent adhesion to tinplate substrates even when exposed to high temperatures. It is in providing the heat resistant resin composition which has this, and the coating material which uses this as a coating-film component.

As a result of examining the adhesion to the tinplate substrate after being exposed to the above-mentioned high temperature, the polyamideimide resin obtained by reacting the diisocyanate compound or diamine compound with tribasic acid anhydride or tribasic acid chloride and basicity It was found that by adding acetylacetone tin to the heat-resistant resin composition obtained from the compound, the decrease in the adhesion to the tinplate substrate was improved, and it was also possible to contribute to the environment by reducing the organic solvent, thereby reaching the present invention.
That is, the present invention provides (A) a polyamideimide resin obtained by reacting a diisocyanate compound or diamine compound with a tribasic acid anhydride or tribasic acid anhydride chloride in a basic polar solvent, and (B) a basic compound. , (C) water and (D) a heat resistant resin composition comprising acetylacetone tin.
In the present invention, the basic compound of the component (B) is combined with the carboxyl group contained in the polyamideimide resin of the component (A) and the carboxyl group obtained by ring opening of the acid anhydride group in the polyamideimide resin. In addition, the present invention relates to a heat resistant resin composition containing 1 to 20 equivalents per 1 equivalent of acid value.
Further, the present invention provides a heat resistant resin composition in which the water of the component (C) is blended in an amount of 5 to 99% by weight based on the total amount of the component (A), the component (B) and the component (C). About.
In the present invention, the polyamideimide resin has a number average molecular weight of 5,000 to 50,000, and an acid value of 10 to 100 mgKOH combined with a carboxyl group obtained by ring opening of a carboxyl group and an acid anhydride group. It is related with the heat resistant resin composition which is / g.
Moreover, this invention relates to the heat resistant resin composition whose basic compound of said (B) component is an alkylamine or an alkanolamine.
The present invention also relates to a heat resistant resin composition in which 0.01 to 20 parts by weight of the acetylacetone tin as the component (D) is blended with respect to 100 parts by weight of the (A) polyamideimide resin.
Furthermore, this invention relates to the coating material which uses the said heat resistant resin composition as a coating-film component.

  When the heat-resistant resin composition of the present invention is used as a coating film, the adhesiveness to the tinplate substrate does not decrease even when exposed to high temperatures, and the organic solvent content is reduced. Among them, it is particularly useful for high heat resistance applications, has no environmental pollution or deterioration of the work environment, and is advantageous for safety and hygiene, and thus has great industrial effectiveness.

  The polyamideimide resin of the present invention is obtained by reacting a diisocyanate compound or diamine compound with a tribasic acid anhydride or tribasic acid chloride as described above. The diisocyanate compound or diamine compound and the tribasic acid anhydride or tribasic acid anhydride chloride are preferably aromatic compounds. Hereinafter, typical compounds used in the method for producing the polyamideimide resin are listed below.

First, examples of the diisocyanate compound include 4,4′-diphenylmethane diisocyanate, xylylene diisocyanate, 3,3′-diphenylmethane diisocyanate, and paraphenylene diisocyanate.
Examples of the diamine include 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, xylylenediamine, phenylenediamine, and the like.
Examples of the tribasic acid anhydride include trimellitic acid anhydride and the like, and examples of the tribasic acid anhydride chloride include trimellitic acid anhydride chloride and the like.
When synthesizing the polyamideimide resin, dicarboxylic acid, tetracarboxylic dianhydride, and the like can be reacted at the same time as long as the properties of the polyamideimide resin are not impaired.

Examples of the dicarboxylic acid include terephthalic acid, isophthalic acid, and adipic acid. Examples of the tetracarboxylic dianhydride include pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and biphenyltetracarboxylic dianhydride. Is mentioned.
The diisocyanate compound or diamine compound, tribasic acid anhydride or tribasic acid anhydride chloride, and the amount of dicarboxylic acid and tetracarboxylic dianhydride used as required are the molecular weight of the polyamideimide resin produced, cross-linking From the viewpoint of the degree, the diisocyanate compound or the diamine compound is preferably 0.8 to 1.1 mol, more preferably 0.95 to 1.08 mol, with respect to 1.0 mol of the total amount of the acid component, In particular, it is preferable to use 1.0 to 1.08 mol. Moreover, it is preferable that dicarboxylic acid and tetracarboxylic dianhydride are used in the acid component in the range whose total amount is 0-50 mol%.

  The polyamideimide resin of the present invention reacts a diisocyanate compound or a diamine compound with a tribasic acid anhydride or tribasic acid chloride in a basic polar solvent. Here, as the basic polar solvent, N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, and the like can be used. In order to perform the polyamide imidization reaction at a high temperature in a short time, N-methyl- It is preferable to use a high boiling point solvent such as 2-pyrrolidone. Moreover, there is no restriction | limiting in particular in the usage-amount of a solvent, However, It is preferable to set it as 100-500 weight part with respect to 100 weight part of total amounts of a diisocyanate component and an acid component. The conditions for synthesizing the polyamide-imide resin are various and cannot be specified in general. Usually, the reaction is performed at a temperature of 120 to 155 ° C., and in an atmosphere of nitrogen or the like in order to reduce the influence of moisture in the air. preferable.

The number average molecular weight of the polyamideimide resin is sampled at the time of resin synthesis, measured by gel permeation chromatography (GPC) using a standard polystyrene calibration curve, and the synthesis is continued until the target number average molecular weight is reached. Therefore, it is managed within the above range.
The polyamideimide resin used in 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, various properties such as heat resistance and mechanical properties of the coating film tend to decrease when it is used as a coating film. When dissolved in a solvent, the viscosity increases and the workability during coating tends to be poor. Therefore, the number average molecular weight of the polyamideimide resin is more preferably 10,000 to 30,000, and particularly preferably 15,000 to 25,000.

  The acid value of the carboxyl group obtained by opening the carboxyl group and the acid anhydride group is preferably 10 to 100 mgKOH / g, and if it is less than 10 mgKOH / g, the carboxyl group that reacts with the basic compound is insufficient. Therefore, water-solubilization becomes difficult, and when it exceeds 100 mgKOH / g, the finally obtained water-based heat-resistant resin composition is easily gelled over time. Therefore, the acid value of the combined carboxyl group obtained by ring-opening the carboxyl group and the acid anhydride group is more preferably 20 to 80 mgKOH / g, and particularly preferably 30 to 60 mgKOH / g.

  In addition, the acid value combining the carboxyl group of the polyamideimide resin and the carboxyl group obtained by ring opening of the acid anhydride group can be obtained by the following method. First, about 0.5 g of polyamideimide resin is taken, about 0.15 g of 1,4-diazabicyclo [2,2,2] octane is added thereto, and about 60 g of N-methyl-2-pyrrolidone and ion-exchanged water are added. Add about 1 ml and stir until the polyamideimide resin is completely dissolved. This is titrated with a potentiometric titrator using a 0.05 mol / l ethanolic potassium hydroxide solution to obtain an acid value that combines the carboxyl groups of the polyamideimide resin and the carboxyl groups obtained by ring opening of the acid anhydride groups. .

  In the present invention, basic compounds include triethylamine, tributylamine, triethylenediamine, alkylamines such as N-methylmorpholine, alkylanilines such as methylaniline, dimethylaniline, monoethanolamine, diethanolamine, triethanolamine, dipropanolamine. Alkanolamines such as tripropanolamine, N-ethylethanolamine, N, N-dimethylethanolamine, cyclohexanolamine, N-methylcyclohexanolamine, and N-benzylethanolamine are suitable. There may be no particular limitation, for example, a caustic compound such as caustic such as sodium hydroxide or potassium hydroxide or aqueous ammonia may be used. Preferably, triethylamine, N-methylmorpholine, triethylenediamine, N, N-dimethylethanolamine is used.

The basic compound is used in an amount of 1 to 20 equivalents per 1 equivalent of the acid value of the carboxyl group and ring-opened acid anhydride group contained in the polyamideimide resin obtained by reacting in the organic solvent. It is done. If the amount is less than 1 equivalent, water-solubilization of the resin becomes difficult. If the amount exceeds 20 equivalents, hydrolysis of the resin is promoted, and the viscosity or properties may be lowered by long-term storage. From this, it is preferable to set it as 2-10 equivalent with respect to the acid value which match | combined the carboxyl group which ring-opened the carboxyl group and the acid anhydride group, and it is especially preferable to set it as 3-8 equivalent.
The basic compound forms a salt with the carboxyl group at the end of the polyamideimide resin to become a hydrophilic group. The salt may be formed in the presence of water, or water may be added after adding the basic compound. The temperature for forming the salt is 0 ° C to 200 ° C, preferably 40 ° C to 130 ° C.

Depending on the type and amount of the basic compound and the method of adding water, the resulting aqueous resin composition is in the form of an emulsion, a translucent solution, a transparent solution, etc., but it is translucent from the viewpoint of storage stability and coating workability. Or it is preferable to make it a clear solution.
As the water, ion-exchanged water is preferably used, and is preferably blended in an amount of 5 to 99% by weight, more preferably 20 to 60% by weight based on the total amount of the components (A), (B) and (C). . If the blending amount is less than 5% by weight, it is not generally referred to as a water-soluble polymer because it contains less water. If it exceeds 99% by weight, it tends not to function as a paint.

  The blending amount of acetylacetone tin is preferably in the range of 0.01 to 20 parts by weight with respect to 100 parts by weight of the polyamideimide resin. When the amount is less than 0.01 parts by weight, the effect of improving the adhesion is reduced, and when the amount exceeds 20 parts by weight, the heat resistance of the coating film tends to gradually decrease. Accordingly, the blending amount of acetylacetone tin is more preferably 0.05 to 10 parts by weight, and particularly preferably 0.1 to 8 parts by weight with respect to 100 parts by weight of the polyamideimide resin. Acetylacetone tin can be mixed with the polyamideimide resin as a solution dissolved in a basic polar solvent. As the basic polar solvent, N-methyl-2-pyrrolidone, N, N-dimethylformamide and the like can be used. Although there is no restriction | limiting in particular about the density | concentration of a solution, For example, 100 weight part of acetylacetone tin is melt | dissolved in 900-4000 weight part of basic polar solvents. The method of blending acetylacetone tin is not limited to this, and other appropriate methods may be used.

The water-based heat-resistant resin composition thus obtained is diluted to an appropriate concentration as needed when used. Diluent solvents include polar solvents such as water, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, as cosolvents, polyols, their lower alkyl etherified products, acetylated products, etc. May be used. For example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, glycerin, trimethylolpropane, isopropyl alcohol, or monomethyl etherified products thereof, monoethyl ether, monoisopropyl etherified products, monobutyl etherified products, dimethyl etherified products, and monofunctionalized products thereof. An acetylated product or the like is used.
The heat-resistant resin composition according to the present invention is applied to an object to be coated and cured to form a coating film on the surface of the object to be coated. When the tinplate substrate is used as an object to be coated, a particularly remarkable effect can be obtained.

EXAMPLES Next, examples of the present invention will be described, but it is needless to say that the present invention is not limited to these examples and includes many other embodiments based on the gist of the invention.
Example 1
106.2 g of trimellitic anhydride, 1455.8 g of 4,4-diphenylmethane diisocyanate, and 2562.0 g of N-methyl-2-pyrrolidone were placed in a flask equipped with a thermometer, a stirrer, and a cooling tube, and dried in a nitrogen stream. The temperature was gradually raised to 130 ° C. over about 2 hours with stirring. The temperature was kept at 130 ° C. while paying attention to the sudden foaming of carbon dioxide gas generated by the reaction, and heating was continued for about 6 hours, and the reaction was stopped to obtain a polyamideimide resin solution.

The polyamideimide resin solution had a nonvolatile content (200 ° C.-2 h) of about 50% by weight and a viscosity (30 ° C.) of about 85.0 Pa · s. The number average molecular weight of the polyamideimide resin was about 17,000, and the acid value of the carboxyl group obtained by ring-opening the carboxyl group and the acid anhydride group was about 40 mgKOH / g. The number average molecular weight was measured under the following conditions.
Model: Hitachi L6000
Detector: Hitachi L4000 type UV
Wavelength: 270nm
Data processor: ATT 8
Column: Gelpack GL-S300MDT-5 × 2
Column size: 8mmφ × 300mm
Solvent: DMF / THF = 1/1 (liter) + phosphoric acid 0.06M + lithium bromide 0.06M
Sample concentration: 5mg / 1ml
Injection volume: 5 μl
Pressure: 49 kgf / cm ² (4.8 × 10 ⁶ Pa)
Flow rate: 1.0 ml / min

2,700 g of this polyamideimide resin solution was put into a flask equipped with a thermometer, a stirrer, and a cooling tube, and gradually heated to 50 ° C. while stirring in a dried nitrogen stream. When the temperature reached 50 ° C., 447.1 g (4 equivalents) of triethylamine was added, and after sufficiently stirring while maintaining the temperature at 50 ° C., ion-exchanged water was gradually added while stirring. Finally, ion-exchanged water was added until it reached 1348.8 g (30 wt%) to obtain a transparent and uniform resin composition.
To 100 parts by weight (non-volatile content: 30% by weight) of the resin composition prepared by the above method, 1.7 parts by weight of N-methyl-2-pyrrolidone solution of acetylacetone tin (non-volatile content: 10% by weight) is blended. A functional resin composition was obtained.

Example 2
In a dry nitrogen stream, 382.9 g of trimellitic anhydride, 503.9 g of 4,4′-diphenylmethane diisocyanate and 886.8 g of N-methyl-2-pyrrolidone were placed in a flask equipped with a thermometer, stirrer and condenser. The temperature was gradually raised to 80 ° C. over about 1 hour with stirring. The temperature was kept at 80 ° C. while paying attention to the sudden foaming of carbon dioxide gas generated by the reaction, and the heating was continued for about 7 hours from the start of heating, and then the reaction was stopped to obtain a polyamideimide resin solution.
The polyamideimide resin solution had a nonvolatile content (200 ° C.-2 h) of about 50% by weight and a viscosity (30 ° C.) of about 80.0 Pa · s. The number average molecular weight of the polyamideimide resin was about 15,000, and the acid value of the carboxyl group obtained by ring-opening the carboxyl group and the acid anhydride group was about 50 mgKOH / g.

200 g of this polyamideimide resin solution was put into a flask equipped with a thermometer, a stirrer, and a cooling tube, and gradually heated to 90 ° C. while stirring in a dried nitrogen stream. When the temperature reached 90 ° C., 70.8 g (8 equivalents) of N-methylmorpholine was added, and the mixture was sufficiently stirred while maintaining at 90 ° C., and then ion-exchanged water was gradually added while stirring. Finally, ion-exchanged water was added until the amount reached 180.5 g (40% by weight) to obtain a transparent and uniform resin composition.
To 100 parts by weight of the resin composition prepared by the above method (nonvolatile content: 22% by weight), 4.4 parts by weight of N-methyl-2-pyrrolidone solution of acetylacetone tin (nonvolatile content: 5% by weight) A functional resin composition was obtained.

Example 3
A flask equipped with 233.8 g of trimellitic anhydride, 98.0 g of benzophenone tetracarboxylic anhydride, 384.6 g of 4,4′-diphenylmethane diisocyanate and 1671.6 g of N-methyl-2-pyrrolidone, equipped with a thermometer, a stirrer and a condenser The mixture was gradually heated to 120 ° C. over about 1 hour with stirring in a dried nitrogen stream. The temperature was gradually raised to 150 ° C. while paying attention to the sudden bubbling of carbon dioxide gas generated by the reaction, and after 5 hours from the start of heating, the reaction was stopped to obtain a polyamideimide resin solution.
The polyamideimide resin solution had a nonvolatile content (200 ° C.-2 h) of about 30% by weight and a viscosity (30 ° C.) of about 2.1 Pa · s. The number average molecular weight of the polyamideimide resin was about 23,000, and the acid value of the combined carboxyl group and acid anhydride group was about 30 mgKOH / g.

200 g of this polyamideimide resin solution was put into a flask equipped with a thermometer, a stirrer, and a cooling tube, and gradually heated to 110 ° C. while stirring in a dried nitrogen stream. When the temperature reached 110 ° C., 17.6 g (6 equivalents) of N, N-dimethylethanolamine was added, and after sufficiently stirring while maintaining at 110 ° C., ion-exchanged water was gradually added while stirring. Finally, ion-exchanged water was added to 217.6 g (50 wt%) to obtain a transparent and uniform resin composition.
To 100 parts by weight of the resin composition prepared by the above method (non-volatile content: 14% by weight), 7.0 parts by weight of N-methyl-2-pyrrolidone solution of acetylacetone tin (non-volatile content: 10% by weight) A functional resin composition was obtained.

Comparative Example 1
Nitrogen obtained by adding 876.9 g of trimellitic anhydride, 1153.8 g of 4,4′-diphenylmethane diisocyanate and 4,738.3 g of N-methyl-2-pyrrolidone to a flask equipped with a thermometer, a stirrer and a condenser. The temperature was gradually raised to 110 ° C. over about 1 hour with stirring in an air stream. The temperature was gradually raised to 120 ° C. while paying attention to the sudden foaming of carbon dioxide generated by the reaction. After continuing the heating for about 8 hours from the start of heating, the reaction was stopped to obtain a polyamideimide resin solution.
The polyamideimide resin solution had a nonvolatile content (200 ° C.-2 h) of about 30% by weight and a viscosity (30 ° C.) of about 1.8 Pa · s. The number average molecular weight of the polyamideimide resin was about 21,000, and the acid value of the carboxyl group obtained by ring-opening the carboxyl group and the acid anhydride group was about 35 mgKOH / g.

Test Example After the paints obtained in Examples 1, 2, and 3 and Comparative Example 1 were applied to a tinplate substrate, they were baked at 300 ° C. for 30 minutes to form a 10 μm-thick coating film plate. About the tinplate board | substrate which formed the coating film, the adhesiveness after exposing to the initial stage and 300 degreeC for a predetermined time was measured according to old JISK5400 (%, crosscut residual rate). The results are shown in Table 1.

In the initial stage of Comparative Example 1, the numerical value of the adhesion has a width because the initial adhesiveness varies among lots, and the numerical values of Examples 1, 2, and 3 have no width between the lots. Indicates that there is no.
From Table 1, the paints obtained in Examples 1, 2, and 3 have a reduced organic solvent content compared to the paints of Comparative Examples, and the paints obtained in Examples 1, 2, and 3 It can be seen that the obtained coating film is remarkably superior in adhesion at the initial stage and after 300 ° C. deterioration as compared with the coating film obtained from the coating material of the comparative example.

Claims (7)

  (A) a polyamideimide resin obtained by reacting a diisocyanate compound or diamine compound with a tribasic acid anhydride or tribasic acid anhydride chloride in a basic polar solvent, (B) a basic compound, and (C ) A heat resistant resin composition comprising water and (D) acetylacetone tin.   (B) With respect to 1 equivalent of the acid value of the basic compound of the component, the carboxyl group contained in the polyamideimide resin of the component (A) and the carboxyl group obtained by ring opening of the acid anhydride group in the polyamideimide resin The heat resistant resin composition according to claim 1, wherein 1 to 20 equivalents are blended.   The heat-resistant resin composition according to claim 1 or 2, wherein water of component (C) is blended in an amount of 5 to 99% by weight based on the total amount of component (A), component (B) and component (C). .   The number average molecular weight of the (A) component polyamideimide resin is 5,000 to 50,000, and the acid value of the carboxyl group obtained by ring-opening the carboxyl group and the acid anhydride group is 10 to 100 mgKOH / g. The heat-resistant resin composition according to any one of claims 1 to 3.   The basic compound as the component (B) is an alkylamine or an alkanolamine. The heat-resistant resin composition according to any one of claims 1 to 4.   The heat resistant resin composition according to any one of claims 1 to 5, wherein 0.01 to 20 parts by weight of component (D) acetylacetone tin is blended with respect to 100 parts by weight of (A) polyamideimide resin.   The coating material which uses the heat resistant resin composition in any one of Claims 1-6 as a coating-film component.