JP2873513B2 - Paint composition and coated aluminum material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a coating composition capable of forming a coating film having excellent corrosion resistance, electrodeposition coating property and the like on an aluminum material, and a molding processability having a coating film obtained from the coating composition. The present invention relates to a coated aluminum material having excellent properties.

[0002]

2. Description of the Related Art In recent years, aluminum materials made of aluminum or aluminum alloy have been used as outer plates of automobile bodies because of their light weight. That is, an automobile body constituted by assembling a steel material and an aluminum material as an outer plate of the automobile body is being put on the market.

[0003] Incidentally, one of the methods of manufacturing an automobile body constituted by assembling such a steel material and an aluminum material is described below.
First, the following method is adopted.

[0004] Steel material forming process─┐ | → Assembly → degreasing → aluminum forming process ┘Chemical treatment → electrodeposition coating → intermediate coating → top coating

[0005] However, the above-mentioned conventional method is inferior in press workability of aluminum material, and when the press oil or rust-preventive oil used for forming is aluminum material,
As compared to steel, it is difficult to degrease sufficiently, and as a result, when subjected to an energizing treatment by zinc phosphate treatment, etc., uneven chemical treatment occurs on the surface of the aluminum material, and the corrosion resistance, water-resistant secondary adhesion, etc. decrease, and the chemical treatment Elution of aluminum occurs inside,
If the amount exceeds a certain amount, there is a problem that the progress of the chemical conversion treatment is hindered. Further, contact between the steel material and the aluminum material is unavoidable, and as a result, there is a problem in that electrolytic corrosion of the aluminum material occurs due to contact with dissimilar metals.

On the other hand, in order to improve the above problems, for example, in order to improve the formability, a method of changing the metal composition in an aluminum alloy (JP-A-58-171547, JP-A-61-201748, JP-A-61-201748, No. 61-201749,
Japanese Patent Application Laid-Open No. 62-27544), a method of roughening the surface of an aluminum material (Japanese Patent Application Laid-Open No. 61-276707, Japanese Patent Application Laid-Open No. 1-21047), and the like. There is no solution to electrolytic corrosion prevention.

Further, in order to prevent the non-uniformity of the chemical conversion treatment, for example, a method of chemically cleaning the surface of an aluminum material (Japanese Patent Application Laid-Open Nos. 1-240675, 1-279788, 2-57692, etc.), There is a method of completely degreasing by lowering the viscosity of rust oil (Japanese Patent Laid-Open No. 2-115385, etc.), and a method of defining the surface area ratio of aluminum and steel in order to enable the same chemical conversion treatment of both ( Japanese Patent Application Laid-Open No. Sho 61-104089), but none of them have solved moldability and the like.

Therefore, in the above-mentioned conventional method, a method has been considered in which the surface of the aluminum material is preliminarily treated, molded using a coated aluminum material coated with a paint film, and assembled with a steel material. In this case, the coating is easily peeled off, and as a result, there is a problem that the corrosion resistance is reduced, the electrodeposition coating property in the subsequent process is poor, and the molding processability is further deteriorated. Practical paints satisfying workability, electrodeposition paintability and the like have not yet been developed.

In view of the above situation, the present invention provides a coating composition for obtaining an aluminum material having excellent chemical conversion resistance, corrosion resistance, moldability, electrodeposition coating property, and the like, and a coated aluminum material coated with the same. The purpose is to provide.

[0010]

That is, the present invention comprises (i) a bisphenol skeleton comprising a bisphenol A skeleton and a bisphenol F skeleton in a weight ratio (95: 5 to 60:40), and an epichlorohydrin skeleton. A coating composition for aluminum materials containing a bisphenol type epoxy resin having two or more epoxy groups in one molecule, and (ii) a lubricant powder having an average particle size of 0.1 to 20 μm; The present invention relates to a coated aluminum material coated on the surface of a treated aluminum material.

Hereinafter, the present invention will be described in detail. The bisphenol-type epoxy resin (i) constituting the coating composition of the present invention comprises a bisphenol skeleton composed of bisphenol A and bisphenol F, a bisphenol skeleton obtained by subjecting epichlorohydrin to a condensation reaction according to a conventional method, and an epichlorohydrin skeleton. A resin having two or more epoxy groups in one molecule, preferably having a molecular weight of about
500-100,000 resins. The condensation reaction between the bisphenols and epichlorohydrin is carried out by bisphenol A
And bisphenol F, and simultaneously reacting with epichlorohydrin.
An epoxy resin obtained by reacting bisphenol F with epichlorohydrin and further reacting by adding bisphenol F or an epoxy resin obtained by reacting bisphenol F with epichlorohydrin and further adding bisphenol A to be reacted are also included in the present invention.

By the way, the bisphenol A type epoxy resin obtained from bisphenol A alone as a bisphenol has a coating film which is excellent in water resistance, chemical resistance, etc.
In addition, while being excellent in adhesion to an aluminum material and adhesion to a top coating film, the coating film is hard and inferior in flexibility, and is slightly inferior in electrodeposition coating property due to its electrical insulation. Was.

The inventors of the present invention have attempted to blend bisphenol A epoxy resin with bisphenol A epoxy resin, but have found that the electrodeposition coating property is not improved. On the other hand, when a bisphenol type resin having two or more epoxy groups in one molecule composed of a bisphenol skeleton composed of a specific ratio of a bisphenol A skeleton and a bisphenol F skeleton and an epichlorohydrin skeleton is used, molding is unexpectedly performed. It was found that the electrodeposition coating property was greatly improved as well as the workability.

In order to exert such effects, it is appropriate that the weight ratio of the bisphenol A skeleton to the bisphenol F skeleton is (95: 5 to 60:40). When the bisphenol A skeleton is larger than the above range, the effect of substitution with the bisphenol F skeleton is not sufficiently recognized. Conversely, when the bisphenol A skeleton is smaller than the above range, the coating film becomes too soft and the corrosion resistance, water resistance, etc. decrease. It is not preferable.

The bisphenol-type epoxy resin used in the present invention has an epoxy group of 20 to further improve alkali resistance, water-resistant secondary adhesion and the like.
A modified epoxy resin in which about 100% is modified with a basic nitrogen compound or a polybasic acid can also be used. Incidentally, as the basic nitrogen compound, for example, n-propylamine, iso
-Propylamine, n-butylamine, sec-butylamine, tert-butylamine, diethylamine, ethylenediamine, diethylenetriamine, triethylenediamine, tetraethylenediamine, propylenediamine, N
-Methylpiperazine, ethanolamine, diethanolamine, N-methylethanolamine, iso-propanolamine, diisopropanolamine, n-propanolamine, ethylethanolamine, 3-methanolpiperidine and the like are mentioned as typical ones.

The polybasic acids include isophthalic acid,
Representatives include terephthalic acid, succinic acid, adipic acid, fumaric acid, itaconic acid, citraconic acid, maleic anhydride, phthalic anhydride, succinic anhydride, citric acid, tartaric acid, oxalic acid, rosin maleic anhydride, benzenetricarboxylic anhydride, etc. It is mentioned as a typical thing. The lubricant powder (ii) constituting the coating composition of the present invention desirably maintains the powder shape even at room temperature and after the formation of the coating film, and the lubricant powder roughens the surface of the obtained coating film, It is blended in order to provide lubricity, that is, to reduce the dynamic friction coefficient and to improve the formability of the coated aluminum material, especially press formability. Representative examples of such lubricant powder include synthetic wax powder and solid lubricant powder.

Examples of the synthetic wax powder include synthetic hydrocarbons; fatty acid esters; fatty acid nitrogen derivatives such as fatty amides and substituted amides; modified waxes such as montan wax derivatives and montan oxide wax; high molecular compounds such as polyethylene wax; chlorinated paraffins Typical examples thereof include chlorinated waxes and the like, and in particular, a synthetic wax powder having a saponification value, being hardly soluble in a solvent, and having a high melting point is desirable.

Examples of the solid lubricant powder include layered solid lubricants such as graphite, molybdenum disulfide, tungsten disulfide, boron nitride, and graphite fluoride; polyvinyl chloride;
Plastic lubricants such as polystyrene, polymethyl (meth) acrylate, polyamide, high-density polyethylene, polypropylene, and polytetrafluoroethylene; and metal soaps such as fatty acids such as calcium, barium, lithium, zinc and aluminum are typical examples. But especially plastic lubricant with high surface lubricity,
Metallic soap is preferred.

About 1 to 50 parts by weight of such a lubricant powder is mixed with 100 parts by weight of the bisphenol-type epoxy resin so that the lubricating property of the coating film is exhibited, and the physical and chemical properties of the coating film are improved. It is desirable because the target strength is also moderate. The average particle size of the lubricant powder is suitably about 0.1 to 20 μm. If the average particle size is too small, such as less than 0.1 μm, the lubricant particles are less likely to be exposed on the coating film. Insufficiency results in problems in molding processability. Conversely, if it exceeds 20 μm, it is problematic in film-forming properties and paint stability. The preferred range of the particle size of the lubricant powder is
It is 0.5 to 12 μm.

The coating composition of the present invention is a paint containing the bisphenol-type epoxy resin (i) and the lubricant powder (ii) described above as essential components, preferably having a solid content of 10 to 40% by weight. As other components, conventionally known components which are appropriately compounded as needed are compounded. Specifically, water,
Various hydrocarbon-based, ester-based, ketone-based, alcohol-based, and amide-based organic solvents; melamine resins, benzoguanamine resins, cross-linking agents such as polyblocked isocyanate compounds; organic or inorganic pigments; dispersants, anti-settling agents; Additives such as leveling agents or various modified resins can be blended.

Next, a method for producing a coated aluminum material of the present invention will be described. Examples of the aluminum material used in the present invention include non-heat-treated Al-Mg-based 5000-based metals, heat-treated Al-Cu-Mg-based 2000-based alloys, which are used for ordinary molded products. Heat treatment type Al-Mg-
Zn-based 7000-based alloy, heat-treated Al-Mg-Si-based 600
0 series alloy, non-heat-treated Al-Mn 3000 series alloy and 4
000 series alloy, non-heat treatment type pure aluminum series 1000
Typical wrought materials and the like are listed as typical examples, but the present invention is not limited to these.

The aluminum material used in the present invention may be prepared by a conventional method, for example, a chromium-based treatment such as a reaction-type chromate treatment such as chromium chromate or phosphoric acid chromate, a coating-type chromate treatment, or an electrolytic chromate treatment, or phosphoric acid. It is an aluminum material that has been subjected to a base treatment by a non-chromium-based treatment such as a zircon treatment, a silane coupling treatment, a titanium coupling treatment, a zircon coupling treatment, and an aluminum coupling treatment.

The above-mentioned coating composition is applied to the surface of the aluminum material subjected to the undercoating treatment by means of spraying, roll coating, shower coating or the like.
Preferably, the coated aluminum material is produced by curing at a temperature of 100 to 250 ° C. It should be noted that although a thin film having a thickness of about several μm can exhibit sufficient performance, it does not prevent further increase in thickness.

The coated aluminum material thus obtained is subjected to electrodeposition coating or ordinary top coating, and is applied to fields such as automobile bodies, home electric appliances, and building materials.

[0025]

According to the coated aluminum material coated with the coating composition of the present invention, a product excellent in corrosion resistance, electrodeposition coating property, adhesion, moldability and the like can be obtained. Further, in the above-described method for manufacturing an automobile body constituted by assembling steel and aluminum, when the coated aluminum material of the present invention is used as the aluminum material, it is durable, that is, resistant to alkali treatment in the degreasing step. When chemical conversion treatment such as zinc phosphate treatment is performed, a chemical conversion film is formed only on steel material and no chemical conversion film is formed on coated aluminum material, eliminating the disadvantage of conventional chemical conversion treatment unevenness. Various effects such as good chemical conversion resistance and prevention of electrolytic corrosion of aluminum due to dissimilar metal contact between steel and coated aluminum can be obtained, and it can be said that the coating and coated aluminum have high practical value.

[0026]

The present invention will be described in more detail with reference to the following examples. In the examples, "parts" and "%" are shown on a weight basis. (Preparation of epoxy resin solution (1)) In a three-necked flask equipped with a reflux condenser, a thermometer and a stirrer, 109.4 parts of bisphenol A, 64.0 parts of bisphenol F and 60 parts of bisphenol F
Of caustic soda was dissolved in 600 parts of water, and the mixture was heated at 50 ° C. for 10 minutes with stirring. Then, 116 parts of epichlorohydrin was added, and the temperature was gradually raised to 100 ° C. in 20 minutes, and kept at this temperature for 40 minutes with stirring.

Then, after cooling, the supernatant water layer was removed by a tilt method, 600 parts of water was further added, the mixture was heated to 90 ° C., stirred vigorously, cooled again, and the supernatant water layer was removed in the same manner. This operation was repeated until the solution no longer showed alkalinity. Finally, water was sufficiently separated.
The resultant was dehydrated by heating at 30 ° C. for 30 minutes to produce an epoxy resin having a molecular weight of about 900.

Ethylene glycol monoethyl ether 200 obtained by heating 200 parts of the obtained epoxy resin to 80 ° C.
Part 1) 50% solids epoxy resin solution (1)
Was prepared. (Preparation of Epoxy Resin Solution (2)) In a flask equipped with a stirrer, a thermometer and a dropping funnel, 729.6 parts of bisphenol A, 160 parts of bisphenol F and 2572 parts of a 10% aqueous solution of caustic soda were added, and stirred at 50 ° C. Heated for minutes. Next, 463 parts of epichlorohydrin was added, and the mixture was heated to 100 ° C. while stirring,
Hold for 0 minutes.

Next, the supernatant water layer was removed by a gradient method, and washing with boiling water was further repeated. After no longer showing alkalinity, the mixture was heated to 150 ° C. and dehydrated to produce an epoxy resin having a molecular weight of about 1400. 300 parts of the obtained epoxy resin was dissolved in 300 parts of ethylene glycol monobutyl ether heated to 80 ° C. to prepare an epoxy resin solution (2) having a solid content of 50%. (Preparation of Epoxy Resin Solution (3)) In a three-necked flask equipped with a reflux condenser, a thermometer, and a stirrer, 680 parts of ethylene glycol monoethyl ether acetate was added, heated to 100 ° C, and then bisphenol A and epichlorohydrin. And an epoxy resin 100 having an epoxy equivalent of 2800 to 3300 obtained by reacting
0 parts were added little by little and dissolved. Next, 25 parts of bisphenol F and 1 part of lithium chloride were added,
The reaction was carried out for about 1 minute to prepare an epoxy resin solution (3) having a molecular weight of about 7,000 and a solid content of 60%. (Preparation of modified epoxy resin solution (4)) In a three-necked flask equipped with a reflux condenser, a thermometer and a stirrer, 109.4 parts of bisphenol A, 64.0 parts of bisphenol F and 60 parts of caustic soda were added to a flask.
An aqueous solution of caustic soda dissolved in 0 parts of water was added, and the mixture was heated with stirring at 50 ° C. for 10 minutes. Next, 116 parts of epichlorohydrin was added, and the temperature was gradually raised.
C. and kept at this temperature for 40 minutes with stirring.

Then, after cooling, the supernatant water layer was removed by a gradient method, and 600 parts of water was further added, the mixture was heated to 90 ° C., stirred vigorously, cooled again, and then the supernatant water layer was removed in the same manner. This operation is repeated until the solution no longer shows alkalinity,
Finally, after sufficiently separating water, 150 ° C. with stirring,
The resultant was dehydrated by heating for 30 minutes to produce an epoxy resin having a molecular weight of about 900.

Ethylene glycol monoethyl ether 200 obtained by heating 200 parts of the obtained epoxy resin to 80 ° C.
And an epoxy resin solution (4 ') having a solid content of 50% was prepared. The epoxy resin solution (4 ') 18
0 parts was heated to 60 ° C., and then diethanolamine 17.
7 parts were added dropwise over 2 hours, and further reacted at 70 ° C. for 3 hours to prepare a modified epoxy resin solution (4) having a solid content of 55%. (Preparation of Modified Epoxy Resin Solution (5)) In a three-necked flask equipped with a reflux condenser, a thermometer, and a stirrer, 680 parts of ethylene glycol monoethyl ether acetate was added, and heated to 100 ° C. 1000 parts of an epoxy resin having an epoxy equivalent of 2800 to 3300 obtained by reacting with epichlorohydrin was added little by little and dissolved. Next, 25 parts of bisphenol F and 1 part of lithium chloride were added and reacted at 200 ° C. for 60 minutes to prepare an epoxy resin solution (5 ′) having a molecular weight of about 7,000 and a solid content of 60%. The epoxy resin solution (5 ') 1
To 167 parts was added 7.5 parts of N-methylethanolamine,
The reaction was carried out in the same manner as in the above solution (4), and the solid content was 60.2%.
To prepare a modified epoxy resin solution (5). (Preparation of modified epoxy resin solution (6)) Bisphenol A10 was placed in a three-necked flask equipped with a reflux condenser, a thermometer, and a stirrer.
An aqueous solution of caustic soda in which 9.4 parts, 64.0 parts of bisphenol F and 60 parts of caustic soda were dissolved in 600 parts of water was added, and the mixture was heated with stirring at 50 ° C. for 10 minutes. Next, 116 parts of epichlorohydrin was added and the temperature was gradually raised to 100 ° C. in 20 minutes, and kept at this temperature for 40 minutes with stirring.

Then, after cooling, the supernatant water layer was removed by the inclined method, 600 parts of water was further added, the mixture was heated to 90 ° C., stirred vigorously, cooled again, and the supernatant water layer was removed in the same manner. . This operation is repeated until the solution no longer shows alkalinity.
Heating and dehydration at 0 ° C. for 30 minutes produced an epoxy resin having a molecular weight of about 900.

Ethylene glycol monoethyl ether 200 obtained by heating 200 parts of the obtained epoxy resin to 80 ° C.
And an epoxy resin solution (6 ') having a solid content of 50% was prepared. 180 parts of this solution (6 ')
C., 2 parts of hydroquinone, 1 part of dimethylbenzylamine and 26.6 parts of phthalic anhydride were added and reacted for 5 hours to prepare a modified epoxy resin solution (6) having a solid content of 56%. (Preparation of modified epoxy resin solution (7)) Ethylene glycol monoethyl ether acetate 68 was placed in a three-necked flask equipped with a reflux condenser, a thermometer and a stirrer.
After adding 0 parts and heating to 100 ° C, 1000 parts of an epoxy resin having an epoxy equivalent of 2800 to 3300 obtained by reacting bisphenol A with epichlorohydrin was added little by little and dissolved. Then bisphenol F25
And 1 part of lithium chloride were added and reacted at 200 ° C. for 60 minutes to prepare an epoxy resin solution (7 ′) having a molecular weight of about 7,000 and a solid content of 60%.

To 1167 parts of the solution (7 ') were added 4.5 parts of hydroquinone, 3.8 parts of dimethylbenzylamine and 14.6 parts of adipic acid, and the reaction was carried out in the same manner as in the solution (6). A 60.5% modified epoxy resin solution (7) was prepared. (Preparation of Epoxy Resin Solution (8)) Bisphenol A type epoxy resin [“Epicoat 1001” (trade name, manufactured by Ciel Chemical Co., Ltd.), epoxy equivalent 450-500]
300 parts of ethylene glycol monoethyl ether 30
0 parts, 50% solids epoxy resin solution (8)
Was prepared. (Preparation of Epoxy Resin Solution (9)) Bisphenol F type epoxy resin [Epiclon 830 (trade name, manufactured by Dainippon Ink and Chemicals, Inc.), epoxy equivalent: about 17
5] 300 parts of ethylene glycol monoethyl ether was dissolved in 300 parts to prepare an epoxy resin solution (9) having a solid content of 50%. Example 1 Epoxy resin solution (1) 2
00 parts, 40 parts of polypropylene wax and 497 parts of propylene glycol monoethyl ether were mixed to prepare a coating material.

The obtained paint was roll-coated on an aluminum material (thickness: 1.0 mm) which had been subjected to various surface treatments shown in Table 1 so as to have a dry film thickness of 3 μm. Each test for baking, corrosion resistance, molding workability, alkali resistance, chemical conversion resistance, electrodeposition coating property, top coat adhesion, water resistance, and paint stability was performed, and the results are shown in the lower column of Table 1. Examples 2 to 7 and Comparative Examples 1 to 4 A mixture obtained by mixing the epoxy resin solution and the lubricant powder in the proportions shown in Table 1 was diluted with propylene glycol monoethyl ether in an amount to give a solid content of 20%. Prepared. The obtained paint was applied in the same manner as in Example 1, and various tests were performed. The results are shown in the lower column of Table 1.

As is clear from Table 1, in the examples using the coating composition of the present invention, the coating stability was good.
Also, it had excellent coating performance. On the other hand, in Comparative Example 1 containing no lubricant powder, the moldability and the like were poor. In Comparative Example 2 in which an epoxy resin composed of only a bisphenol A skeleton was used as the bisphenol skeleton, moldability, electrodeposition coating property, and the like were poor. Further, in Comparative Example 3 using an epoxy resin composed of only a bisphenol F skeleton as the bisphenol skeleton, corrosion resistance was improved.
The alkali resistance, chemical conversion resistance, water resistance, etc. were poor. In Comparative Example 4 using a liquid lubricant, electrodeposition coating properties, top coat adhesion, water resistance, and the like were poor.

[0037]

[Table 1]

Note 1) "Shamrock Wax S-363" (Shamroc
k Chemicals company name), average particle size 5 μm Note 2)
"Seridust 3910" (trade name, manufactured by Hoechst), average particle size 8 μm Note 3) "Hitasol GP-60" (trade name, manufactured by Hitachi Powdered Metals), average particle size 0.5 μm Note 4) "Rubron L-2" (Trade name, manufactured by Daikin Industries, Ltd.), average particle size 5μ
m Note 5) “Famex A-12” (trade name, manufactured by Ajinomoto Co.), average particle size 10 μm Note 6) “SC-100”
(Trade name of Sakai Chemical Industry Co., Ltd.), average particle size 3μm Note 7)
“MD-40” (trade name, manufactured by Hitachi Powdered Metals Co., Ltd.), average particle size 1 μm Note 8) “KF945 (A)” (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), liquid Note 9) Cross-cut the painted surface of the test plate And a salt spray test based on JIS-Z-2371
Performed for 00 hours and observed the occurrence of white rust. ○: No abnormality at all △: Spots of white rust ×: White rust Note 10) Cylindrical drawing of a test plate punched out at 84 mmφ with a diameter of 50 mmφ and a depth of 25 mm (BHF = 1 ton) ) And after processing, perform a salt spray test based on JIS-Z-2371 for 400 hours and observe the state of white rust occurrence ○: no white rust △: less than 5% white rust ×: 5% or more white rust Note 11) After immersion in an alkaline degreasing solution at 50 ° C., washing with water and drying, 100 mm squares were cut with a cutter knife, and the residual ratio of the coating film after the peeling test was measured using a cellophane tape. rate
100% ○: ３ 3 minutes １００ 100% △:
〃 〃 ９０ 90-99% ×: 〃
〃 ８９ 89% or less Note 12) Test plate at 45 ° C
3 min., Immersed in zinc phosphate treatment solution for 3 minutes, and observed after washing and drying. ○: No coating film peeling, uniform coating film as before chemical conversion treatment ×: Coating film peeling. Amine-coated epoxy resin-blocked isocyanate-based cationic electrodeposition paint is applied at a bath temperature of 28 ° C. and 100 V × 3 minutes, and baked at 165 ° C. for 20 minutes to observe the appearance of the coating film (area 100 cm ² ). ○: Gas pin and crater generation 0 to 5 points △: Gas pin and crater generation 6 to 20 points ×: Gas pin and crater generation 20 points or more Note 14) 100 pieces of the 1 mm-thick cationic electrodeposition coated plate obtained in Note 13) Is cut with a cutter knife and a peeling test is performed using a cellophane tape to measure the residual ratio of the electrodeposited coating film. ○: 95 to 100% △: 90 to 94% ×: 89% or less Note 15) Obtained by Note 13) Horn After immersing the on-electrodeposited plate in water at 40 ° C and drying, perform a peel test in the same manner as in Note 14) to measure the residual ratio of the electrodeposited film. ◎: 500 hours after immersion time Residual rate 100% ○: ３００ 300 〃 100% △: 〃 〃 ９０ 90-99% ×: 〃 〃 ８９ 89% or less Note 16) After leaving each sample of the composition shown in Table 1 at 50 ° C. for 3 weeks, Observation of paint state when left at room temperature for 1 day ○: Slight separation occurred, redispersible after stirring for 30 minutes △: Considerable amount of separation occurred, 〃 ×: 不可能 Redispersible after stirring for 30 minutes

────────────────────────────────────────────────── ─── Continuing on the front page (72) Osamu Yada, Inventor 3-Shimonaga, Nishinasuno-cho, Nasu-gun, Tochigi Pref. 1172-4 (72) Susumu Ogawa 3-359-337, Mihara, Otawara-City, Tochigi Pref. JP-A-4-168172 (JP, A) JP-A-3-111468 (JP, A) JP-A-3-111466 (JP, A) JP-A-60-94466 (JP, A) JP-A-2-155958 (JP JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C09D 163/02 C09D 5/08 C08G 59/06 C08G 59/14

Claims (4)

(57) [Claims] (I) a bisphenol A skeleton composed of a bisphenol A skeleton and a bisphenol F skeleton in a weight ratio (95: 5 to 60:40), and an epichlorohydrin skeleton, wherein two or more molecules are contained in one molecule; Bisphenol type epoxy resin having epoxy group, and (ii) average particle size
A coating composition for aluminum materials containing a lubricant powder of 0.1 to 20 μm. 2. The composition of claim 1, further comprising (i) a modified epoxy resin obtained by modifying the epoxy resin according to claim 1 with a basic nitrogen compound or a polybasic acid, and (ii) a lubricant powder having an average particle size of 0.1 to 20 μm. Paint composition for aluminum materials. 3. A coated aluminum material obtained by applying the coating composition according to claim 1 on a surface of the aluminum material which has been subjected to a base treatment. 4. The coated aluminum material according to claim 3, which is used for an automobile body.