JPH06101075A - Rust preventing pigment composition - Google Patents

Abstract

PURPOSE:To provide a rust preventing pigment composition which is non- polluting and has an excellent rust preventing capability effective even on non- ferrous metal based materials such as zinc, aluminum, etc., and also a superior durability of the rust preventing capability. CONSTITUTION:This rust preventing pigment composition is obtained by using a condensed phosphate which is hardly soluble in water such as aluminum dihydrogen tripolyphosphate, aluminum metaphosphate or a phosphoric acid based layer compound such as layer cerium phosphate, layer titanium phosphate, layer zirconium phosphate together with a magnesium compound such as magnesium oxide, hydrated magnesium oxide, magnesium carbonate, magnesium borate in a 10:1 to 10:10 weight ratio.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a rust preventive pigment composition. More specifically, the present invention is pollution-free and zinc,
The present invention relates to a rust preventive pigment composition having excellent rust preventive power even for non-ferrous metal materials such as aluminum.

[0002]

2. Description of the Related Art Conventionally, as rust preventive pigments for oil-based paints, solvent-based paints, etc., mainly chromium-based pigments (eg zinc chromate, strontium chromate etc.), lead-based pigments (eg lead tin, Lead chromate, lead cyanamide, calcium leadate, etc., phosphoric acid pigments (eg zinc phosphate, calcium phosphate etc.), molybdic acid pigments (eg zinc molybdate), boric acid pigments (eg metaboric acid) Barium and the like have been used (for example, Japanese Patent Publication No. 53-31495, Japanese Patent Publication No. 54-5399, and Japanese Patent Laid-Open No. 56-12).
9638 publication).

These rust-preventive pigments for paints are usually used for an object to be coated of an iron-based material which is most required to prevent corrosion, and for an object to be coated of a non-ferrous metal-based material, for example, Calcium leadate, magnesium oxide and the like have been used to prevent white rust on zinc (for example, JP-A-56-113383), and strontium chromate has been used to prevent thread rust for duralumin.

[0004]

However, although the chrome-based rust-preventive pigments and the lead-based rust-preventive pigments have excellent rust-preventive power, they contain harmful metals such as chromium (hexavalent chromium) and lead. There was a safety issue, such as the possibility of impairing human health.

Further, molybdic acid type anticorrosion pigments, boric acid type anticorrosion pigments, magnesium type anticorrosion pigments and the like are so-called pollution-free anticorrosion pigments containing no harmful metals, and have no problem in terms of safety. Although there were few, there was a problem that the rust preventive power was low and the durability was poor.

Therefore, a condensed aluminum phosphate-based rust preventive pigment has been proposed as a pollution-free rust preventive pigment (for example, JP-A-55-160059), but this is superior to iron-based materials. Although it has anticorrosive properties, it cannot be said that the anticorrosive properties are sufficient for nonferrous metal materials such as zinc and aluminum.

That is, the corrosion mechanism of non-ferrous metal materials is
Unlike iron-based materials, pitting corrosion, thread rust, white rust, etc. occur,
Since the adhesiveness of the paint is reduced, a material having an excellent anticorrosive power for ferrous materials cannot necessarily have an excellent anticorrosive power for nonferrous metal materials.

By the way, recently, non-ferrous metal-based materials have come to be widely used industrially due to demands for improved corrosion resistance and weight reduction. In the present situation, no rust-preventive pigment that is pollution-free and has excellent rust-preventive power has not been found.

Therefore, it is an object of the present invention to provide a rust preventive pigment which is pollution-free and has excellent rust preventive power even for non-ferrous metal materials.

[0010]

Means for Solving the Problems In order to develop a pollution-free rust-preventive pigment having excellent rust-preventing power even for non-ferrous metal-based materials, the present inventors have prepared various phosphoric acid-based compounds as a base. As a result of diligent examination of the combined use of the compound with the compound, a composition in which a water-insoluble condensed phosphate or a phosphoric acid-based layered compound and a magnesium compound are used in combination is harmless to non-ferrous metal-based materials. However, they have found that they have excellent rust preventive power, and arrived at the present invention.

That is, the rust-preventive pigment composition of the present invention comprises a condensed phosphate or phosphoric acid-based layered compound which is poorly soluble in water and a magnesium compound. None of the constituents contain hexavalent chromium or lead, and it is pollution-free, and strongly prevents white rust and thread rust not only for iron-based materials but also for non-ferrous metal-based materials. In addition, it exhibits excellent rust preventive power, and the adhesion of the coating film to the material can be enhanced accordingly.

The rust preventive pigment composition of the present invention is
Not only conventional solvent-based paints, but also water-based paints (water-soluble resin-based, dispersion-based, emulsion-based, etc.) that have been attracting attention in relation to recent environmental problems
It is also applicable to powder coatings.

The rust preventive pigment composition of the present invention has excellent rust preventive power even for non-ferrous metal materials, which is different from the conventional pollution-free rust preventive pigment composition. Metal-based materials include zinc, aluminum, tin, nickel, copper, alloys containing these metals as the main materials, and iron-based materials plated with these non-ferrous metals, or
It refers to a non-ferrous metal-based material coated with a phosphate-based coating typified by Parkerizing treatment.

Next, each component constituting the rust preventive pigment composition of the present invention, its role, and the amount used will be described in detail.

The water-insoluble condensed phosphate used in the present invention is not particularly limited as long as it can be used as a rust preventive pigment, but its solubility is usually 10 g / liter as P ₂ O _5. It is preferably water or less.

Specifically, as the above-mentioned sparingly water-soluble condensed phosphate, for example, aluminum pyrophosphate, calcium pyrophosphate, tin pyrophosphate, cerium pyrophosphate, copper pyrophosphate, iron pyrophosphate, titanium pyrophosphate,
Pyrophosphates such as magnesium pyrophosphate and manganese pyrophosphate, tripolyphosphates such as aluminum tripolyphosphate, iron tripolyphosphate, aluminum metaphosphate, iron metaphosphate, calcium metaphosphate, tin metaphosphate, cerium metaphosphate, manganese metaphosphate, metaphosphate Examples thereof include molybdic acid salts and metaphosphates such as silver metaphosphate, but aluminum dihydrogen tripolyphosphate and aluminum metaphosphate are particularly preferable because of their large rust-preventive power.

On the other hand, as the phosphoric acid-based layered compound which is hardly soluble in water, M (HP
O ₄ ) ₂ · XH ₂ O [M is a tetravalent metal such as Ce, Ti, Zr, Sn and X is 0 to 2], and these are two-dimensional. It is known to have a simple layered structure.

Specific examples of the phosphoric acid-based layered compound include layered cerium phosphate, layered titanium phosphate,
Examples thereof include layered zirconium phosphate and layered tin phosphate, and layered cerium phosphate, layered titanium phosphate and layered zirconium phosphate are particularly preferable.

The above-mentioned sparingly water-soluble condensed phosphate or phosphoric acid-based layered compound is the main component that exerts the rust preventive power in the rust preventive pigment composition of the present invention.
It is a kind of solid acid, and its pH is as low as 1 to 3, and when these are blended to prepare a paint, the paint becomes acidic, the viscosity of the paint increases and gelation easily occurs, and the stability of the paint is improved. There is a risk that they will be damaged, and these alone will not be able to exert sufficient rust preventive power against non-ferrous metal materials.

Therefore, in the present invention, by using a magnesium compound in combination with the sparingly water-soluble condensed phosphate or phosphoric acid layered compound, the acidity of the condensed phosphate or phosphoric acid layered compound can be improved. In addition to eliminating troubles, it also improves rustproofing ability against non-ferrous metal materials.

Examples of the above magnesium compound include inorganic magnesium salts such as magnesium oxide, hydrous magnesium oxide, magnesium carbonate, basic magnesium carbonate, magnesium phosphate, magnesium borate, magnesium metaborate and magnesium silicate, and magnesium stearate. Although an organic magnesium salt such as magnesium sulfonate can be used, it is particularly preferable to use magnesium oxide, hydrous magnesium oxide, magnesium carbonate, magnesium borate and the like.

In the present invention, the combined ratio of the sparingly water-soluble condensed phosphate or phosphoric acid-based layered compound and the magnesium compound is preferably in the range of 10/1 to 10/10 by weight.

If the proportion of the magnesium compound used is more than the above range, the amount of the sparingly water-soluble condensed phosphate or phosphoric acid-based layered compound decreases, and the rust preventive power based on them cannot be sufficiently exerted. When the combined ratio of the magnesium compound is less than the above range, the action of neutralizing the pH of the condensed phosphate or the phosphoric acid-based layered compound decreases, and the stability of the coating composition may be impaired, and the magnesium compound The anti-corrosion ability against non-ferrous metal materials, which is exerted based on the combined use of the above, is reduced.

In the present invention, the reason why the non-ferrous metal-based material has an excellent anticorrosive power by using the magnesium compound together with the sparingly water-soluble condensed phosphate or phosphoric acid-based layered compound, Although it has not been clarified at present, by mixing magnesium compounds in the sparingly water-soluble condensed phosphate or phosphoric acid layered compound, it has some inhibitory effect on the occurrence of white rust and thread rust of non-ferrous metal materials. It is considered to be effective.

The rust-preventive pigment composition of the present invention is a combination of a sparingly water-soluble condensed phosphate or phosphoric acid-based layered compound and a magnesium compound. The mixing can be performed by either dry mixing or wet mixing. In particular, when it is necessary to disperse the rust-preventive pigment composition in a resin having poor stability in forming a coating, it is preferable to previously wet-react these components by a wet mixing method.

The wet reaction may be carried out batchwise or continuously, and the components to be added in the reaction may be mixed first. The reaction temperature during the wet reaction is suitably in the range of room temperature to 80 ° C., and the reaction time is usually 30 minutes to 3 hours. After completion of the reaction, the reaction slurry is filtered and dried, and the obtained dried product is pulverized to obtain the desired rust preventive pigment composition.

When the anticorrosive pigment composition of the present invention is used as a paint, various kinds of paint resins can be used without particular limitation. Examples thereof include boil oil, oily varnish, phenol resin, amino resin, and the like. Epoxy resin, urethane resin, vinyl resin, acrylic resin, fluorine resin,
Synthetic resins for various paints such as silicone resin and polyester resin, rubber derivatives such as chlorinated rubber and cyclized rubber, and other fibrin derivatives can be used alone or in combination.

When the anticorrosive pigment composition of the present invention is dispersed in a resin for paint, the condensed phosphate or phosphoric acid-based layered compound which is poorly soluble in water and the magnesium compound are mixed in advance without mixing them. They may be separately added to the resin for paint so that they are mixed in the resin.

[0029]

EXAMPLES Next, the present invention will be further described with reference to examples. However, the present invention is not limited to only those examples. In addition, hereinafter, various amounts such as the compounding amount are based on the weight.

Example 1 Aluminum dihydrogen tripolyphosphate [K-
100 g of fresh # 100P (trade name)] and magnesium oxide [manufactured by Kyowa Chemical Industry Co., Ltd., magnesium oxide T]
(Trade name)] 40 g was dry-mixed to obtain a rust preventive composition.

Example 2 100 g of aluminum dihydrogen tripolyphosphate and 100 g of magnesium carbonate similar to those used in Example 1 were dry mixed to obtain a rust preventive composition.

Example 3 100 g of aluminum dihydrogen tripolyphosphate and 100 g of hydrous magnesium hydroxide similar to those used in Example 1 were put into 600 g of warm water at 80 ° C. and stirred for about 1 hour. Then, it was dehydrated, dried and pulverized to obtain a rust preventive composition.

Example 4 Aluminum Metaphosphate [K-Bond # 9, manufactured by Teika Co., Ltd.
0 (trade name)] 100 g and magnesium oxide 40 g were dry mixed to obtain a rust preventive pigment composition.

Example 5 Aluminum metaphosphate [K-bond # 9, manufactured by Teika Co., Ltd.
0 (trade name)] 100 g and magnesium borate 80 g were dry mixed to obtain a rust preventive pigment composition.

Example 6 Commercially available cerium oxide (reagent grade 99% CeO ₂ ) 19.
5g and 85% phosphoric acid 31.2g (P ₂ O ₅ / CeO ₂
With a molar ratio of 1.2) in a porcelain crucible, and the resulting mixture is placed in an electric furnace set to a temperature of 180 ° C. together with the crucible, and steam heated to 180 ° C. is blown thereinto,
Cerium oxide and phosphoric acid were reacted at 180 ° C. for 4 hours in the presence of water vapor.

The obtained reaction product had a pale yellow color. The reaction product was washed with water, dehydrated, dried, and then pulverized. The obtained pulverized product was found to have [Ce
It (HPO ₄₎ is a crystalline layered cerium phosphate represented ₂ · 1.33H In ₂ O] was found. The interlayer distance of the crystalline layered cerium phosphate was measured by powder X-ray diffractometry and found to be 15.9Å.

Then, 100 g of the pulverized crystalline layered cerium phosphate obtained as described above and 60 g of magnesium oxide were dry-mixed to obtain a rust preventive composition.

Example 7 Titanium hydroxide [Ti (OH) ₄ ] 11.6 g and 85%
Phosphoric acid 34.6 g (P ₂ O ₅ / TiO ₂ molar ratio 1.
5) and 5) were stirred and mixed in a porcelain crucible in the same manner as in Example 6, and the obtained mixture was placed in an electric furnace whose temperature was set to 210 ° C. together with the crucible, and steam heated to 210 ° C. was blown in to steam. Titanium hydroxide and phosphoric acid in the presence of
The reaction was carried out at 0 ° C for 5 hours.

The obtained reaction product was white in color.
The reaction product was washed with water, dehydrated, dried, and then pulverized.
The obtained pulverized product was analyzed by X-ray diffraction measurement, and [Ti (HP
It O ₄₎ is a crystalline layered titanium phosphate represented by ₂ · 2H ₂ O] was found. The interlayer distance of this crystalline layered titanium phosphate was measured by powder X-ray diffraction measurement and found to be 11.6Å.

Then, 100 g of the pulverized crystalline layered titanium phosphate obtained as described above and 40 g of magnesium oxide were dry-mixed to obtain a rust preventive composition.

Example 8 23.5 g of ZrOCl ₂ which is a water-soluble zirconium salt
Is dissolved in 500 ml of pure water, and 85% phosphoric acid 4 is added to the solution.
6.1 g (P ₂ O ₅ / ZrO ₂ molar ratio of 1.5) was gradually added dropwise with stirring. As a result, a white gel-like precipitate was obtained. After centrifuging this, 85% phosphoric acid was added and mixed, and then the whole crucible was placed in an electric furnace set to 190 ° C. to 190 ° C. Heated steam was blown in, and the reaction was carried out at 190 ° C. for 4 hours in the presence of steam.

The reaction product obtained was white in color.
The reaction product was washed with water, dehydrated, dried, and then pulverized.
The obtained pulverized product was analyzed by X-ray diffraction and found to have [Zr (HP
It O ₄₎ is a crystalline layered zirconium phosphate represented by ₂ · 2H ₂ O] was found. The interlayer distance of this crystalline layered zirconium phosphate was measured by powder X-ray diffraction measurement and found to be 12.2Å.

Next, 100 g of the pulverized crystalline layered zirconium phosphate obtained as described above and 80 g of magnesium carbonate were put into 600 g of warm water at 60 ° C. and stirred for about 1 hour. Then, it was dehydrated, dried and pulverized to obtain a rust preventive composition.

Next, using the rust preventive pigment compositions of Examples 1 to 8 above, baking type epoxy resin rust preventive paints were prepared, respectively, and after forming a coating film, a salt spray test was conducted to obtain the rust preventive effect. I checked. The results are shown in Test Example 1. Also,
For comparison and comparison, zinc phosphate, strontium chromate, zinc molybdate, zinc-treated condensed aluminum phosphate, and magnesium oxide as rust preventive pigments were used to prepare baking type epoxy resin-based rust preventive paints,
A similar test was conducted.

Baking type polyester resin type anticorrosive paints were prepared using the anticorrosive pigment compositions of Examples 1 to 8, and after forming a coating film, a salt spray test was conducted to examine the anticorrosion effect. It was The results are shown in Test Example 2. Further, in Test Example 2 as well, for comparison and comparison, zinc phosphate, strontium chromate, zinc molybdate, zinc-treated condensed aluminum phosphate, and magnesium oxide were used as anticorrosion pigments, respectively, and baked type polyester resin type A rust paint was prepared and the same test was conducted.

Further, using the anticorrosive pigment compositions of Examples 1 to 8, a normal dry type epoxy resin anticorrosive paint was prepared, and after forming a coating film, a salt spray test was conducted to show its anticorrosive effect. Examined. The results are shown in Test Example 3. Also, for comparison, in Test Example 3, zinc phosphate, strontium chromate, zinc molybdate, zinc-treated condensed aluminum phosphate, and magnesium oxide were used as anticorrosion pigments, and each of them was a normally dry epoxy resin. A system anticorrosive paint was prepared and the same test was conducted.

Test Example 1 A baking type epoxy resin-based anticorrosive paint having the composition shown in Table 1 was prepared, and after forming a coating film, a salt spray test was conducted to examine its anticorrosion effect.

1-1 Preparation of Anticorrosion Paint With the formulation shown in Table 1, 13 kinds of baking type epoxy resin-based antirust paint primer compositions were prepared.

[0049]

[Table 1]

* 1 Types of antirust pigments 1: Antirust pigment composition of Example 1 2: Antirust pigment composition of Example 2 3: Antirust pigment composition of Example 3 4: Antirust of Example 4 Rust pigment composition 5: Antirust pigment composition of Example 5 6: Antirust pigment composition of Example 7 7: Antirust pigment composition of Example 7 8: Antirust pigment composition of Example 8 9: Zinc Phosphate 10: Strontium Chromate 11: Zinc Molybdate 12: K-White # 84 (trade name, rust preventive pigment made of zinc treated condensed aluminum phosphate manufactured by Teika) 13: Magnesium oxide * 2 Trade name, oil Epoxy resin manufactured by Chemical Shell Epoxy Co., Ltd. * 3 Product name, solid content 62 manufactured by Dainippon Ink and Chemicals, Inc.
% Butylated Urea Resin Solution

The top coating composition (top coat) is
Fukkaron paint (trade name) manufactured by Kansai Paint Co., Ltd. was used.

1-2 Coating and Coating Conditions Each of the above 13 types of baking type epoxy resin-based anticorrosive paints was coated on a plate to be coated under the following coating conditions, and baked at a temperature of the following conditions to form a coating film.

Coating: Bar coater coating Coating plate: Hot dip galvanized steel plate Bt # 37 treated plate (manufactured by Japan Test Panel Industry Co., Ltd.) Film thickness: Primer 9 ± 1 g / m ² Top coat 36 ± 1 g / m ² Baking : Primer MT (Coating plate temperature) 18
0 ° C-35 seconds Topcoat MT (Coating plate temperature) 250 ° C-50
Second

1-3 Salt Spray Test A test plate prepared by forming a coating film on the plate to be coated as described above was cut into the plate to reach the plate to be coated, and then statically placed in a salt water sprayer in which the in-machine temperature was kept at 35 ° C. After standing, a 5% aqueous sodium chloride solution was sprayed on the coating film at 1 kg / cm ² for 1,000 hours, and the occurrence of white rust on the test plate from the cut portion and the swelling of the coating film were observed.

1-4 Test Results The results of the salt spray test are shown in Table 2 for each type of rust preventive pigment.

The rust-preventing effect is evaluated by the effect of preventing white rust on the test plate and the effect of preventing swelling (swelling) of the coating film.
The evaluation criteria are as follows. The evaluation criteria for the white rust prevention effect are ASTM D610-68 (197).
0), and the evaluation standard for the blistering prevention effect is AST
According to MD 714-59 (1965). Therefore, as is clear from the following evaluation criteria, the higher the evaluation value is, the better the white rust occurrence preventing effect and the blistering occurrence preventing effect are.

Evaluation Criteria for Preventing White Rust Generation 5: White rust occurrence area less than 0.1% 4: White rust occurrence area 0.1% to less than 1% 3: White rust occurrence area 1% to less than 10% 2: White rust occurrence area 10% or more and less than 33% 1: White rust occurrence area 33% or more

Evaluation criteria for blistering prevention effect 5: 8F or less 4: 8M, 6F 3: 8MD, 6M, 4F 2: 8D, 6MD, 4M, 2F 1: 6D, 4MD or more, 2M or more

[0059]

[Table 2]

As shown in Table 2, the anticorrosive pigment compositions of Examples 1 to 8 have a high evaluation value of the anticorrosive effect against both white rust and blisters, and are the same as conventional pollution-free anticorrosive pigments. Not only for zinc phosphate, zinc molybdate, magnesium oxide, etc., but also for the rust preventive effect compared to the strontium chromate chromium-based pigment.

Test Example 2 A baking type polyester resin-based anticorrosive paint having the composition shown in Table 3 was prepared, and after forming a coating film, a salt spray test was conducted to examine its anticorrosion effect.

2-1 Preparation of Anticorrosion Coating 13 types of primer compositions for baking type polyester resin anticorrosion coating were prepared with the formulations shown in Table 3.

[0063]

[Table 3]

* 4 Types of antirust pigments 1: Antirust pigment composition of Example 1 2: Antirust pigment composition of Example 2 3: Antirust pigment composition of Example 3 4: Antirust pigment of Example 4 Rust pigment composition 5: Antirust pigment composition of Example 5 6: Antirust pigment composition of Example 7 7: Antirust pigment composition of Example 7 8: Antirust pigment composition of Example 8 9: Zinc Phosphate 10: Strontium Chromate 11: Zinc Molybdate 12: K-White # 84 (trade name, rust preventive pigment made of zinc treated condensed aluminum phosphate manufactured by Teika) 13: Magnesium oxide * 5 Trade name, large 60 solids manufactured by Nippon Ink Chemical Co., Ltd.
% Polyester resin liquid * 6 Solid name 60 manufactured by Dainippon Ink and Chemicals, Inc.
% Butylated melamine resin liquid * 7 Aromatic solvent manufactured by Exxon Chemical Co., Ltd.

In addition, for the top coating (top coat),
Fukkaron paint (trade name) manufactured by Kansai Paint Co., Ltd. was used.

2-2 Coating and Coating Conditions The above 13 kinds of baking type polyester resin-based anticorrosive paints were coated on the coated plate under the following coating conditions and baked at the temperature of the following conditions to form a coating film.

Coating: Bar coater coating Coating plate: Hot-dip galvanized steel plate Bt # 37 treated plate (manufactured by Japan Test Panel Industry Co., Ltd.) Film thickness: Primer 10 ± 1 g / m ² Top coat 28 ± 1 g / m ² Baking : Primer MT (Coating plate temperature) 20
5 ° C-50 seconds Topcoat MT (coated plate temperature) 225 ° C-50
Second

2-3 Salt Water Spray Test A test plate prepared by forming a coating film on a plate to be coated as described above was cut into a plate to reach the plate to be coated, and statically placed in a salt water sprayer in which the in-machine temperature was kept at 35 ° C. Then, a 5% aqueous sodium chloride solution was sprayed onto the coating film at 1 kg / cm ² for 400 hours, and the occurrence of white rust on the test plate from the cut portion and the swelling of the coating film were observed.

2-4 Test Results The results of the salt spray test are shown in Table 4 for each type of rust preventive pigment. The evaluation criteria for the rust preventive effect are the same as in Test Example 1.

[0070]

[Table 4]

As shown in Table 4, the anticorrosive pigment compositions of Examples 1 to 8 have an anticorrosive effect against both white rust and blistering even when the baking type polyester ester resin anticorrosive paint is used. The evaluation value was high, and the rust-preventing effect was superior not only to the conventional pollution-free rust preventive pigments such as zinc phosphate, zinc molybdate and magnesium oxide, but also to the chromium-based pigment strontium chromate.

Test Example 3 An ordinary dry type epoxy resin-based anticorrosive paint having the composition shown in Table 5 was prepared, and after forming a coating film, a thread rust generation test was conducted to examine the anticorrosion effect against the occurrence of thread rust.

3-1 Preparation of Anticorrosion Paint 13 types of primer compositions of normally dry type epoxy resin-based anticorrosion paint were prepared with the formulations shown in Table 5.

[0074]

[Table 5]

* 8 Types of antirust pigments 1: Antirust pigment composition of Example 1 2: Antirust pigment composition of Example 2 3: Antirust pigment composition of Example 3 4: Antirust pigment of Example 4 Rust pigment composition 5: Antirust pigment composition of Example 5 6: Antirust pigment composition of Example 7 7: Antirust pigment composition of Example 7 8: Antirust pigment composition of Example 8 9: Zinc phosphate 10: Strontium chromate 11: Zinc molybdate 12: K-white # 84 (trade name, anti-corrosion pigment made of zinc treated condensed aluminum phosphate manufactured by Teika) 13: Magnesium oxide * 9 Trade name, oil Resin solution with a solid content of 70% obtained by dissolving an epoxy resin manufactured by Chemical Shell Epoxy Co., Ltd. in a mixed solvent of xylene and isopropanol * 10 Polyamide resin liquid with a solid content of 60% manufactured by General Mill Co., Ltd. * 11 Xylene / Butano -Le / Chiruserosorubu / methyl ethyl ketone = 6/2/1/1 (weight ratio)

3-2 Coating and Coating Conditions The above 13 kinds of normally dry type epoxy resin-based anticorrosive coatings were coated on the coated plate under the following coating conditions and dried at room temperature for 1 week to form a coating film.

Coating: Bar coater coating Plate to be coated: Polished aluminum plate 6063S (manufactured by Japan Test Panel Industry Co., Ltd.) Film thickness: 20 ± 1 μm

3-3 Thread Rust Generation Test A test plate prepared by forming a coating film on a plate to be coated as described above was cut to reach the plate to be coated, and a salt spray test was conducted for 24 hours, followed by 40 ° C. It was evaluated by immersing it in a thermo-hygrostat kept at −85% and observing the generation and progress of thread rust from the cut portion over time for 4 weeks.

3-4 Test Results The results of the thread rust generation test are shown in Table 6 for each type of rust preventive pigment.

The rust prevention effect is evaluated by the effect of preventing thread rust from occurring on the test plate, and the evaluation criteria are as follows. As is clear from the evaluation criteria below, the higher the evaluation value, the better the effect of preventing the occurrence of thread rust.

Evaluation Criteria for Preventing Thread Rust Generation 5: Thread Rust Generation Length Less Than 2 mm 4: Thread Rust Generation Length 2 mm to Less than 4 mm 3: Thread Rust Generation Length 4 mm to Less than 6 mm 2: Thread Rust Generation Length 6 mm or more and less than 10 mm 1: Thread rust occurrence length 10 mm or more

[0082]

[Table 6]

As shown in Table 6, the rust preventive pigment compositions of Examples 1 to 8 have a high evaluation value of the effect of preventing thread rust generation, and the rust preventive effect against thread rust is also high. In addition to zinc phosphate, zinc molybdate, magnesium oxide, etc., the rust-preventing effect was superior to that of strontium chromate, which is a chromium-based pigment.

[0084]

As described above, the rust-preventive pigment composition of the present invention is non-polluting and has an excellent rust-preventing effect on non-ferrous metal materials, and a salt spray test for 1,000 hours or It survived the thread rust generation test for 4 weeks and was excellent in the durability of the rust preventive effect.

Claims (5)

[Claims] 1. A rust preventive pigment composition comprising a condensed phosphate or phosphoric acid-based layered compound which is poorly soluble in water and a magnesium compound. 2. The rust preventive pigment composition according to claim 1, wherein the condensed phosphate which is sparingly soluble in water is aluminum dihydrogen tripolyphosphate or aluminum metaphosphate. 3. The rust preventive pigment composition according to claim 1, wherein the poorly water-soluble phosphoric acid-based layered compound is layered cerium phosphate, layered titanium phosphate or layered zirconium phosphate. 4. The rust preventive pigment composition according to claim 1, wherein the magnesium compound is magnesium oxide, hydrous magnesium oxide, magnesium carbonate or magnesium borate. 5. A combined use ratio of a sparingly water-soluble condensed phosphate or a phosphoric acid-based layered compound and a magnesium compound is
The rust preventive pigment composition according to claim 1, which has a weight ratio of 10/1 to 10/10.