JPH0275670A - Cationic electrodeposition coating material based on nitrogen-containing alkyd resin - Google Patents

Abstract

PURPOSE:To obtain the title material excellent in storage stability and anticorrosiveness by using an epoxy resin-modified product of a specified nitrogen-containing alkyd resin as a vehicle component. CONSTITUTION:An epoxy resin-modified nitrogen-containing alkyd resin obtained by modifying an N-containing alkyd resin obtained by condensing an amine compound having at least two, on the average, active hydrogen atoms in the molecule (e.g., trimethanolamine) with a polybasic acid (e.g., phthalic anhydride) and, optionally, a polyalcohol (e.g., ethylene glycol) and a fatty acid (e.g., coconut oil fatty acid) with an epoxy resin (e.g., Epikote 1004) is used as a vehicle component.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a nitrogen-containing alkyd resin-based cationic electrolyte whose vehicle component is an epoxy resin modified product of a nitrogen-containing alkyd resin having a nitrogen atom in its main skeleton. Regarding coating paint.

(Prior art) Conventional electrodeposition coating methods use water as a solvent, so
It has many advantages such as there is no danger of fire or explosion, it is possible to automate the process and apply large quantities continuously over a long period of time, and it is easy to control the coating thickness. Therefore, it has been widely used for a long time.

The paint used in this electrodeposition coating method is an anionic electrodeposition paint that uses a water-soluble alkyd resin as the base resin, and is low-cost.
It is used as an industrial paint due to its non-polluting properties. However, the water-soluble alkyd resin paint has the disadvantage that the alkyd resin is easily hydrolyzed and the alkyd resin becomes insoluble in water, resulting in poor storage stability of the paint.
Further, there is a drawback that the corrosion resistance of the coating film formed from this material is not sufficient.

In recent years, cationic electrodeposition paints have been widely used in place of anionic electrodeposition paints because they form cured coatings with essentially excellent corrosion resistance due to the electrodeposition mechanism and the basicity of the resin components.

As a cationic electrodeposition paint, a cationic electrodeposition paint whose base resin is an epoxy resin into which a cationic group has been introduced is widely used because it forms a coating film with high corrosion resistance. Compared with alkyd resins, there are problems such as high cost and poor weather resistance, and the appearance of cationic electrodeposition paints using water-soluble alkyd resins has been desired in this field.

(Problems to be Solved by the Invention) The present invention was made for the purpose of achieving these demands, and as a result of research efforts from various viewpoints, an alkyd resin containing nitrogen atoms in the main skeleton was developed. They have discovered that the above object can be achieved by using a modified resin obtained by modifying the above with an epoxy resin as a vehicle component for cationic electrodeposition, and have completed the present invention.

(Means for Solving the Problems) The present invention relates to an amine compound containing an average of two or more active hydrogens in one molecule, a polybasic acid, and, if necessary, a polyhydric alcohol and a fatty acid. This invention relates to a nitrogen-containing alkyd resin-based cationic electrodeposition paint whose vehicle component is an epoxy resin-modified nitrogen-containing alkyd resin obtained by modifying a nitrogen alkyd resin with an epoxy resin.

The epoxy resin-modified nitrogen-containing alkyd resin, which is the vehicle component of the paint of the present invention, is made by condensing a component containing a polybasic acid and an amine compound as essential components, and further adding a polyhydric alcohol and a fatty acid as necessary. It is obtained by modifying the obtained nitrogen-containing alkyd resin with an epoxy resin.

Polybasic acids are composed of polycarboxylic acid compounds having two or more carboxyl groups in one molecule, such as succinic acid, adipic acid, azelaic acid, sebacic acid, dodecynylsuccinic acid, and these compounds. Aliphatic saturated dibasic acids such as anhydrides, aliphatic unsaturated dibasic acids such as maleic acid, fumaric acid, itaconic acid and their anhydrides, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid and aromatic polybasic acids such as their anhydrides, tetrahydrophthalic acid, methylcyclohexenetricarboxylic acid, hexahydrophthalic acid, Himic acid, Hett's acid, tetrachlorophthalic acid, cyclohexanedicarboxylic acid, methylhexahydrophthalic acid, and hexahydrophthalic acid. Examples include alicyclic polybasic acids such as hydrotrimellitic acid and anhydrides thereof, and one or more selected from these can be used.

The amine compound with which the polybasic acid is reacted has in its molecule an active hydrogen that can react with the carboxyl group in the polyhydrochloric acid compound, and moreover, the number of active hydrogens per molecule is 2 or more on average, preferably 2 to 2 on average. It has six ranges. The above active hydrogen is, for example, 0H1NH (C-NH-C bonded secondary
NH, (C-NH, bonded primary amino group), etc.

As the amine compound, for example, general formula (I) CI) where R8, R1, R1 and R4 are the same or different,
Each represents a hydrogen atom, an alkyl group, an aryl group, or a cycloalkyl group, n represents an integer of 1 to 4, and m represents 0.
Indicates an integer of ~4, provided that when m is 0, R1, R2
, R1 and R4 are hydrogen atoms. Further, when m is 1, at least one of R, , R, , R, and R4 has a hydrogen atom.

An amine compound having a primary amino group and/or a secondary amino group represented by formula (II), where R5 and R6 are the same or different and each represents a hydrogen atom, an alkyl group, an aryl group, or a cycloalkyl group. group, n and m have the same meanings as above, provided that m is O
In the case of , either one of R6 and R6 is a hydrogen atom.

Alkanolamine compounds having one hydroxyl group and a primary amino group or a secondary amino group in one molecule represented by and the general formula (Ill) OH-C, H2n\N-R, (Ill) 0H-CnH ,n In the formula, R1 represents a hydrogen atom, an alkyl group, an aryl group, a cycloalkyl group, -C,H,, -OH group, and n has the same meaning as above.

Examples include polyhydric alkanolamine compounds having two or more hydroxyl groups in one molecule represented by:

In the above formulas (1), (11) and (III), the "alkyl group" includes, for example, methyl, ethyl,
n-propyl, 1so-propyl, n-butyl, 1s
o-butyl, 5ec-butyl, tert-butyl, n
-hexyl, 2-ethylhexyl, lauryl, etc., among which preferred is a lower alkyl group of 01 to 4. Moreover, as the "cycloalkyl group", a cyclohexyl group is preferably mentioned. Furthermore, examples of the "aryl group" include phenyl group, tolyl group, xylyl group, and the like.

- Specific examples of formula (1) include NH, -C, H
4-NH,, NH, -C, H, -NH-C, H, -NHa, NHx
+C* H--NH)yC* H4-NHa, NH2-
C3Hfi-NH-C, H, -NH,, (C2H@),
-N-C3H, -NH.

etc.

Further, as specific examples of formula (1), for example, 0H-CH, -NH,, 0H-C, H4-NH,, 0H-CH, -NH-CHl, 0H-C, H4-NH-CH ,,0l-1-C,H,-NH-C,H,,0H-C,H4
-NH-C,H,,0H-C,H,-N)I-Cffi H4CH,,0H
-C, H, -NH-C, H,, CH oh CH2 CH* -CH,, 0H-C, H, -NH,, 0H-C, H, -N) (-CH,, OH-C- Ha -NH-Ca H7,0)1-CI
H@-NH-C3H? , 0H-C3H, -NH-C
,H,CH,,0H-C,H,-NH-C4H,, CH,-CH1,0H-C,H4-NH-C! H, -NH,,OH-+
C2H4-NHhC*H4-NHx, CH, -CH-C
Ha-NH-CIH, -NH.

OH etc.

Furthermore, as a specific example of the formula (Ill), example ^(O
H-C* H-hNHl (CH, -CH-CH-h-NHl OH (CH5-CH-CH*)yNCH-1OH (OH-Cm H4) s -N, (OH-Cw H4) *-N CHa , (OH-
Cz H4) * -N C* Hs, (OH-C
Spirit H4) m -N Cs Ht, (OH-C,t
H,), -N-C4H,, (CHs -CHCH* h
-N OH and the like.

The ratio of both components in the condensation reaction of the above polybasic acid and amine compound is as follows: polybasic acid/amine compound (
Based on the molar ratio), a range of 0.5 to 12 is suitable, particularly preferably 0.7 to 1.0. 3 to 55% by weight, preferably 5 to 40% by weight, based on the total amount (including the total amount in a system in which polyhydric alcohol and fatty acid are used together).

If the amine compound is less than 3% by weight, the water solubility of the paint and the corrosion resistance of the coating film will be poor, while if it is more than 55% by weight, the weather resistance and water resistance of the coating film will be poor, which is not preferred.

Examples of polyhydric alcohols that can be used as necessary include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, butanediol, neopentyl glycol, 1,2-1l, 3-12, 3-11. 4-butylene glycol, bentanediol, 2.3-dimethylpropanediol, 1.6-12.5-hexanediol, hydrogenated bisphenol A, cyclohexane dimetatool, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, ' Trimethylolethane, trimethylolpropane, glycerin, diglycerin, dipentaerythritol, sorbitol, etc., and one or more selected from these can be used.

Further, as the fatty acid, drying oil (including semi-drying oil) fatty acid (iodine value of about 100 or more), non-drying oil fatty acid (iodine value of less than about 100), and these fats and oils can be used.As the drying oil fatty acid, For example, safflower oil fatty acids, linseed oil fatty acids, soybean oil fatty acids, sesame oil fatty acids, poppy oil fatty acids, eno oil fatty acids, hempseed oil fatty acids, grape kernel fatty acids, corn oil fatty acids, tall oil fatty acids, sunflower oil fatty acids, cottonseed oil fatty acids, walnut oil fatty acids. Examples include oil fatty acids, tung oil fatty acids, dehydrated castor oil fatty acids, rice bran oil fatty acids, and their dimer acids. Non-drying oil fatty acids include, for example, coconut oil fatty acids. The amount of these fatty acids used is based on the polybasic The total amount of the acid component, the polyhydric alcohol component, and the fatty acid is suitably in the range of 0 to 60% by weight, preferably 5 to 60% by weight, and more preferably 10 to 45% by weight.

The nitrogen-containing alkyd (grease resistance is obtained by adding a polybasic acid and an amine compound, and further including a polyhydric alcohol and a fatty acid as necessary) under the same conditions as for a normal alkyd resin, e.g.
It can be produced by reacting at 0 to 250°C for 1-t5 hours.

Next, the epoxy resin which is a modified resin of the nitrogen-containing alkyd resin is a polyepoxide having an average of 2 or more epoxy groups per molecule, and a polyepoxide having an average of 1 or more epoxy groups per molecule obtained by modifying the polyepoxide with a monobasic acid. It is an epoxide having an epoxy group of Examples of polyepoxides include epoxy resins obtained from bisphenol and shrimp halohydrin, hydrogenated bisphenol and shrimp halohydrin, or epoxy resins obtained from bisphenol and β- shrimp halohydrin. Among these, particularly preferred are epoxy resins obtained from bisphenol and shrimp halohydrin.
12, Epicote 152, Epicote 154, Epicote 1001, Epicote 1002. Epicote 1003
, Epicote 1055, Epicote 1004, Epicote 1007. Epicote 1009, Epicote 1olO
, Ciba Geigy Araldite 6071, Araldite 6084, Araldite 6097, Araldite 6
099, Araldite 7004, Ebicuron N-730, Ebicuron N-740 manufactured by Dainippon Ink Co., Ltd., and the like.

In addition to the above, a) polyglycidyl ethers of novolak resins, b) polyglycidyl ethers of polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin, and trimethylolpropane, C) adipic acid, phthalic acid,
Polyglycidyl ethers of polycarboxylic acids such as dimer acid, d) alicyclic olefins, polyepoxides obtained by epoxidizing 1,2-polybutadiene, and the like can be used. These polyepoxides are preferably used in combination with the epoxy resin in an amount that does not impair its corrosion resistance (generally, 50 parts by weight or less per 100 parts by weight of the epoxy resin).

As the monobasic acid for modifying the polyepoxide, for example, the fatty acid used in the nitrogen-containing alkyd resin can be used.

The blending ratio of epoxy resin is 100% nitrogen-containing alkyd resin.
About 1 to 50 parts by weight, preferably about 3 to 3 parts by weight
It is in the range of 0 parts by weight. If the blending ratio is less than about 1 part by weight, coating film performance such as adhesion to materials, corrosion resistance, chemical resistance, and flexibility will be insufficient; on the other hand, if the blending ratio is about 50 parts by weight,
If the amount exceeds 1 part by weight, the pigment dispersibility will be poor, resulting in defects such as spots, color separation, and gloss spots in the paint film.Also, the pigment component and resin component will separate during paint storage, and the pigment component will be lost in the storage container. It is not preferable because it settles at the bottom of the tank and hard cakes, making redispersion difficult.

The epoxy resin-modified nitrogen-containing alkyd resin used in the present invention is prepared by combining the nitrogen-containing alkyd fit resin and the epoxy resin under conventionally known reaction conditions (epoxy group and carboxyl group or amino group) at typically 130 to 200°C. The coating of the present invention is produced by neutralizing the basic groups in the epoxy resin-modified nitrogen-containing alkyd resin with an acidic neutralizing agent and then dispersing it in water. It can be produced by quaternizing some or all of the nitrogen atoms of the nitrogen-containing alkyd 131 fat with an epoxy group-containing resin or compound such as an epoxy resin or glycidyl ether, and then dispersing the product in water.

In order to supplement the water dispersibility of the epoxy resin-modified nitrogen-containing alkyd resin, it is possible to use an epoxy resin-modified nitrogen-containing alkyd resin in which a basic group is added to the terminal of the nitrogen-containing alkyd resin.

The epoxy resin-modified nitrogen-containing alkyd resin is about 10 to 20
0. In particular, it is preferable to have an amine value of 30 to 150. If the amine value is smaller than IO, the water dispersibility of the epoxy resin-modified nitrogen-containing alkyd resin will be poor;
If it is larger than 00, the weather resistance of the coating film will be poor, which is not preferable.

As the acidic neutralizing agent, for example, formic acid, acetic acid, hydroxyacetic acid, propionic acid, dimethylolpropionic acid, butyric acid, etc. can be suitably used. The acidic neutralizer is usually added in an amount of about 0.2 to 1.5 equivalents, preferably about 0.3 to 1.0 equivalents, based on the basic group of the nitrogen-containing alkyd resin.

Furthermore, the coating material of the present invention can be prepared by blending a crosslinkable resin with the epoxy resin-modified nitrogen-containing alkyd resin and crosslinking and curing it in a three-dimensional network by heating or drying. The crosslinkable resin is an OH in an epoxy resin-modified nitrogen-containing alkyd resin.
It is a compound having a functional group (for example, an amino group, an alkyl ether group, a blocked or unblocked isocyanate group, etc.) that crosslinks with a functional group such as , NH, N). Alkyl etherified melamine (M fat, urea resin, benzoguanamine resin, etc.) modified with lf1 or more selected from alcohols (1 to 5 carbon atoms).Isocyanate compounds include 1, for example, tolylene diisocyanate, tolylene diisocyanate, and There are adducts with trimethylolpropane, diphenylmethane diisocyanate, methylene diisocyanate, hexamethylene diisocyanate, adducts between hexamethylene diisocyanate and trimethylolpropane, xylylene diisocyanate, lysine diisocyanate, etc. Blocking agents include phenol, thiourea, Examples include methanol, propatool, n-butanol, 7-butanol, ethyl acetoacetate, dimethyl malonate, and ε-caprolactam.

In the paint of the present invention, the composition ratio of the epoxy resin-modified nitrogen-containing alkyd resin and the crosslinkable resin is based on the total amount of both components: 100% of the epoxy resin-modified nitrogen-containing alkyd resin
~60% by weight, especially 85-70% by weight, crosslinkable resin 0~
40% by weight, especially 15-30% by weight is preferred.

In the paint of the present invention, in order to mix the crosslinkable resin such as the melamine resin, urea resin, benzoguanamine resin, etc. with the epoxy resin-modified nitrogen-containing alkyd resin having the OH functional group and crosslink and cure it by heating, the OH functional group As an epoxy resin-modified nitrogen-containing alkyd resin having a hydroxyl value of 20 to 300, preferably 30 to 200 and an acid value of 0.5
-50, preferably 1-25, heating conditions for crosslinking and curing are about 120-200°C
Approximately 10 to 40 minutes seems to be sufficient.

In addition to the above-mentioned components, the coating material of the present invention may contain coloring pigments, extender pigments, antirust pigments, coating surface conditioners, curing accelerators, hydrophilic organic solvents, and the like, which are known per se.

In order to form a coating film using the paint of the present invention, for example, an electrodeposition bath with a solid content of approximately 5 to 30% by weight is prepared, and the object to be coated is placed in the bath at a liquid temperature of approximately 5 to 30°C. This can be carried out by applying a voltage between the cathode and the counter electrode to form an electrodeposition coating film on the object to be coated, and drying it in the air or baking it (for example, at about 40 to 200° C. for about 10 to 40 minutes). The object to be coated can be used without any particular restrictions as long as it has conductivity, such as steel plates,
Aluminum plates, alloys (turnsheets, etc.), plated steel plates whose surfaces are plated with zinc, tin, chromium, aluminum, etc., or steel plates whose surfaces are treated with phosphoric acid, zinc phosphate, iron phosphate, etc. Treated steel plates etc. can be used.

(Action and Effect of the Invention) In the present invention, the ester bond and amide bond adjacent to the nitrogen atom generated by the reaction between a polybasic acid and an amine compound are resistant to hydrolysis accelerating substances (e.g. water, alkali, acid, etc.). Because it is a chemically stable bond, the paint of the present application whose vehicle component is an epoxy resin-modified nitrogen-containing alkyd resin that has this bond is different from conventional paints whose vehicle component is a water-soluble alkyd resin that does not have this bond. It can exhibit superior effects on storage stability compared to .

In addition, for example, an electrodeposition coating film formed from a paint containing a cationic electrodeposition resin having a hydroxyl group and a curing agent such as an amino resin is a coating film with excellent curability due to the cationic groups in the resin acting on a negative catalyst. However, the epoxy resin-modified nitrogen-containing alkyd resin used in the present invention has the above-mentioned structure. Because of this, its basicity is weak, and a coating film with excellent curability can be formed without inhibiting the curing reaction. Moreover, due to the properties of the epoxy resin-modified nitrogen-containing alkyd resin itself, a coating film with excellent corrosion resistance can be formed. The effect is remarkable.

(Example) Next, the present invention will be described in detail with reference to Examples.

Production Example 1 18.0 parts by weight of triethanolamine, 17.5 parts by weight of ethylene glycol, 47.6 parts by weight of phthalic anhydride, 16.9 parts by weight of coconut oil fatty acid, 23 parts by weight of Epicote 1001.
．． A mixture consisting of 1 part by weight was reacted at 160 to 230°C for 10 hours while stirring under a nitrogen gas atmosphere to obtain a nitrogen-containing alkyd resin (A-1).

The resin (A-1) had an acid value of 2, an amine value of 66.4, an epoxy content of 10% by weight, and an oil length of 16.6.

Production Example 2 Tripropaturamine 14.3 parts by weight, Diesel 54.2
parts by weight and 20 parts by weight of Epikote 1004 at 160 to 230°C while stirring under a nitrogen gas atmosphere.
The mixture was reacted for 9 hours to obtain a nitrogen-containing alkyd resin (B-1).

The resin had an acid value of 1O, an amine value of 37.4, and an epoxy content of 20% by weight.

Production Example 3 11.3 parts by weight of methyljetanolamine, 5.9 parts by weight of ethylene glycol, 11.7 parts by weight of glycerin, 44.5 parts by weight of phthalic anhydride, 26.6 parts by weight of tall oil fatty acid, 15 parts by weight of Epicote 1007. A mixture consisting of parts by weight was reacted at 160 to 230°C for 11 hours while stirring under a nitrogen gas atmosphere to obtain a nitrogen-containing alkyd resin (C-1).

Production Example 4 To 100 parts by weight of the nitrogen-containing alkyd resin (A-1) obtained in Production Example 1, 7.8 parts by weight of acetic acid, 16.9 parts by weight of butyl glycidyl ether, and 1.3 parts by weight of deionized water were added.
The quaternary ammonium salt of A-1 (D-1
) was obtained.

Production Example 5 87.1 parts of 2.4-toluene diisocyanate was added to 143 parts
2.4-toluene diisocyanate was slowly added to 2-ethylhexanol with external cooling to maintain the reaction mixture below 100° C. to obtain 2-ethylhexanol diurethane (E-1).

Production Example 6 16.7 parts by weight of trimethylolpropane, 17.7 parts by weight of ethylene glycol, 48.4 parts by weight of phthalic anhydride,
A mixture consisting of 17.2 parts by weight of coconut oil fatty acid was reacted at 160 to 230° C. for 10 hours while stirring under a nitrogen gas atmosphere to obtain an alkyd resin (F-1). The resin (F-
1) had an acid value of 2, a hydroxyl value of 125.7, and an oil length of 18.5.

Production Example 7 100 parts by weight of the quaternary ammonium salt (D-1) obtained in Production Example 4 was dissolved in 24 parts by weight of butyl cellosolve, and deionized water was added to prepare an aqueous solution having a solid content of 20% by weight.

600g of the above aqueous solution, 190g of titanium white R602, 3.6g of carbon black MA, 107g of aluminum silicate
Glass peas were added to the mixture and stirred vigorously for 2 hours using a high-speed rotating mixer to obtain a pigment paste CG-1) with good water dispersibility.

Example 1 100 parts by weight of resin (A-1) obtained in Production Example 1, Production Example 5
After dissolving 31.8 parts of the resin (E-1) obtained in 24 parts by weight of butyl cellosolve and 22.8 parts by weight of isopropanol, 7.8 parts by weight of acetic acid was added to neutralize the solution. Deionized water was added to prepare an aqueous dispersion having a solid content concentration of 20% by weight. The pigment paste (G-1) produced in Production Example 7 was added to this dispersion.
130 parts by weight of was added and mixed with deionized water to obtain an electrodeposition coating liquid with a solid content concentration of 15% by weight.

Example 2 100 parts by weight of resin (B-1) obtained in Production Example 2, Production Example 5
After dissolving 31.8 parts by weight of the resin (E-1) obtained in 24 parts by weight of butyl cellosolve and 22.8 parts by weight of isopropanol, 7.8 parts by weight of acetic acid was added to neutralize the solution. Deionized water was added to prepare an aqueous dispersion having a solid content concentration of 20% by weight. The pigment paste (G-1) produced in Production Example 7 was added to this dispersion.
Add 130 parts by weight of and add deionized water to make the solid concentration 15% by weight.
An electrodeposition coating liquid was obtained.

Example 3 100 parts by weight of the resin (B-1) obtained in Production Example 2, 30 parts by weight of Nikaratsuku MX40 (manufactured by Sanso Chemical Co., Ltd., trade name, melamine resin), 24 parts by weight of butyl cellosolve, 22.8 parts by weight of isopropanol After dissolving in parts by weight, 7.8 parts by weight of acetic acid was added to neutralize it. Next, deionized water was added to give a solid content concentration of 2.
A 0% by weight aqueous dispersion was prepared. Production Example 7
130 parts by weight of the pigment paste (G-1) prepared above was added to deionized water to obtain an electrodeposition coating liquid having a solid content concentration of 15% by weight.

The cationic electrodeposition coating liquids of Examples 1 to 3 were cured to a film thickness of 25 to 3
A zinc phosphate treated steel plate was cathodic electrodeposited to give a coating thickness of 0 u, and after washing with water and baking, an electrodeposited coating was obtained.

Comparative Example A comparison paint was obtained using 100 parts by weight of the resin (F-1) obtained in Production Example 6 and 31.8 parts by weight of the resin (E-1) obtained in Production Example 5.

The paint was applied to a zinc phosphate treated steel plate to a cured film thickness of 2511 mm, and a cured film was obtained by baking.

These results are summarized in the table.

(×1) Paint surface condition: Visual judgment, smoothness, repellency,
The presence or absence of dents was investigated.

(*2) Corrosion resistance: After cross-cutting the coating film to reach the substrate and testing it with Tsuruto Spray for 500 hours, apply adhesive cellophane tape to the cut area, peel it off, and remove the coating from the cut area. Both sides of the membrane were examined during peeling.

(*3) Acid resistance: Aqueous N/1O sulfuric acid solution was dropped onto a horizontally supported painted surface, and the condition of the painted surface was examined after leaving it for 48 hours. ○ indicates that no abnormality is observed.

(*4) The same procedure as above (*3) was carried out except that an alkali-resistant 2N15 caustic soda aqueous solution was used. O indicates that no abnormality was observed, and Δ indicates that whitening and glossy pixelation were observed.

(*5) Bending resistance: radius of curvature 4m with the coating outside
The state of the painted surface when bent at m was examined. 0 indicates that no abnormality was observed, and Δ indicates that cracking and peeling were observed.

(*6) Solvent resistance: The coated plate was immersed in toluene (20°C) for 5 hours, and then the condition of the coated surface was examined. ○ indicates that no abnormality is observed.

(*7) Adhesion: After soaking the coated plate in water for 48 hours at 40°C, pull it out and leave it for 1 hour. 100 stitches were made, adhesive cellophane tape was pasted on the surface, and the number of coatings remaining after the tape was removed was examined.

(*8) Storage stability: Colored paints stored at 30°C for 20 days were tested. The condition of the paint was determined by examining the presence or absence of pigment sedimentation; O indicates that no abnormality was observed, and Δ indicates that pigment precipitation was clearly observed.

Claims (1)

[Claims] 1. A nitrogen-containing alkyd resin obtained by condensing an amine compound containing an average of two or more active hydrogens per molecule, a polybasic acid, and, if necessary, a polyhydric alcohol and a fatty acid, is modified with an epoxy resin. A nitrogen-containing alkyd resin-based cationic electrodeposition paint containing an epoxy resin-modified nitrogen-containing alkyd resin as a vehicle component.