JP2001081572A - Rust stabilization treating agent for steel, rust stabilization treating method and rust stabilization- treated steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rust stabilization treating agent for steel having functions of preventing the permeation of corrosive anions in flied salt or the like, executing the formation of stabile rust with high efficiency and also preventing flowing rust with high efficiency, moreover improving weathering characteristics in the case a film is slowly weathered and is replaced by stable rust and remarkably improving its appearance in the meanwhile from the point after the treatment to the time in which the film is replaced by stable trust, to provide a rust stabilization treating method and to provide a rust stabilization-treated steel. SOLUTION: This trust stabilization treating agent for steel contains the components of (a) to (c):(a) a resin composition obtained by blending a substrate resin with a compound having an anionic functional group, a compound having a conjugated double bond and a compound having a light-collapsible functional group; (b) salt composed of anions and counter cations having trapping and depositing action to iron ions; and (c) pigment by a ratio of 30 to 70 pts.wt. 100 pts.wt. of the solid content of the rust stabilization treating agent. As to the rust stabilization treating method for steel, the treating agent is applied on the surface of steel, and drying is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rust stabilizing agent, a rust stabilizing method, and a rust stabilizing steel for steel. More specifically, it is mainly applied to weatherable steel materials obtained by adding alloying elements such as Cu, Ni, Cr, P, and Mo, and efficiently generates stable rust of weatherable steel,
Prevents poor appearance due to flowing rust etc. in the stable rust formation process,
Furthermore, after forming stable rust under the treatment agent film, the steel material is intended to significantly improve the weathering characteristics when the treatment agent gradually weathers, and to make it extremely unlikely that the appearance will be deteriorated due to cracking of the film or film-like peeling. The present invention relates to a rust stabilizing agent, a rust stabilizing method, and a rust stabilizing steel.

[0002]

2. Description of the Related Art Weather-resistant steel is a low alloy steel containing a small amount of elements such as Cu, Ni, Cr, P, and Mo. A layer (stable rust) forms spontaneously. Then, after the rust layer is formed, the corrosion of the steel material thereafter is reduced, and finally the steel material has the characteristic that the corrosion hardly progresses.

[0003] Such a weather-resistant steel material is applied to various steel materials such as a shaped steel, a steel plate and a steel pipe, and has a wide range of uses as a structure such as a bridge or a steel tower, but has the following problems.

In other words, when a weather-resistant steel material is used barely, it takes a long period of 5 years or more until stable rust with strong protection is formed on the surface of the steel material. There is a problem that the rusted juice contaminates the surrounding environment and impairs the appearance.

Therefore, a technique has been disclosed which solves the above problem by performing a surface treatment called a rust stabilization treatment on the surface of the weatherable steel. This rust stabilization treatment is performed, for example, in Japanese Patent Application Laid-Open No. 56-127774, a two-layer film of a cationic type film and an anionic type film is disclosed. JP-A-2666673 discloses a steel material coated with an organic resin having a stable rust formation promoting action, in which a two-layer coating in which a resin layer having excellent weather resistance and corrosion resistance is provided as a layer and an upper layer is provided.

[0006]

However, of the above-mentioned prior arts, the method according to Japanese Patent Publication No. 56-33991 has a poor appearance in the process of deterioration of the coating film during the formation of stable rust. There is a problem that the coating film is cracked and a film-like peeling occurs. In addition, the response to incoming salt is insufficient,
There is a disadvantage that the ability to form stable rust in a corrosive environment is poor.

[0007] Further, two or more layers of coating are required, and there is a disadvantage that coating workability and coating cost are increased. Patent 266
In the patent publication 6673, since stable rust is formed at an early stage, poor appearance after treatment is inevitable, and contamination of the surrounding environment due to flowing rust or the like is also a problem. It is also unclear whether the rust formed earlier functions as true stable rust for a long time.

In the method described in Japanese Patent Application Laid-Open No. 56-127774, a stable rust forming environment is prepared by preventing the flow rust with a cationic type coating and increasing the durability against salt with an anionic type coating. It is intended to form stable rust, but it is necessary to form two or more different coatings,
There is a problem in painting workability. In addition, there is a problem in that the ratio of the anion type film is limited due to the balance with the ability to form stable rust, and that sufficient flying salt resistance cannot be exhibited.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and prevents formation of stable rust by preventing permeation of corrosive anions such as flying salt and allows efficient formation of stable rust. A rust stabilizing agent and a rust stabilizing agent for steel, which, in addition to the function of preventing rust, improve the weathering characteristics when the film gradually weathers and is replaced by stable rust, and significantly improve the appearance after treatment after it is replaced with stable rust. An object of the present invention is to provide a stabilizing method and a rust stabilizing steel material.

[0010]

Means of the present invention for solving the above problems are as follows. (1) A rust stabilizing agent for steel, comprising the following components (a) to (c): (A) a resin composition in which a compound having an anionic functional group, a compound having a conjugated double bond, and a compound having a photo-degradable functional group are blended in a base resin; (C) a pigment in a proportion of 30 to 70 parts by weight per 100 parts by weight of the solid content of the rust stabilizing agent;

(2) A rust stabilizing agent for steel, comprising the following components (a ') to (c): (A ′) a resin composition in which a compound having a conjugated double bond and a compound having a photodegradable functional group are mixed with a resin having a negative fixed charge, and (b) an anion having a trapping and depositing action on iron ions. (C) 30 to 7 parts by weight per 100 parts by weight of the solid content of the rust stabilizing agent.
0 parts by weight pigment.

(3) A rust stabilizing agent for a steel material comprising the following components (a ″) to (c): (a ″) A compound having an anionic functional group is blended with the base resin A resin composition, wherein at least one of the base resin and the compound having an anionic functional group has an aromatic ring in a molecule, and has the base resin and the anionic functional group. A resin composition in which the compound has a functional group capable of reacting with each other to form a photo-degradable functional group, or a resin composition which is a compound; (b) a salt comprising an anion having a trapping and depositing action on iron ions and a counter cation; (C) 30 to 70 parts by weight of a pigment per 100 parts by weight of the solid content of the rust stabilizing agent.

(4) The rust stabilizing agent according to the above (1) or (2), wherein the compound having a conjugated double bond is a compound having a phenyl group and / or a phenylene group.

(5) The rust stabilizing method according to any of (1), (2) and (4), wherein the compound having a photodegradable functional group is a compound having an ester group. Processing agent.

(6) The rust stabilizer according to (3), wherein the resin composition of (a ″) is a resin composition obtained by blending a carboxylic anhydride with a fatty acid-modified aromatic epoxy resin. Chemical treatment agent.

(7) The above (1) to (6), wherein the anion having a trapping and depositing action on the iron ion of the salt of the above (b) is a phosphate ion and / or a molybdate ion. The rust stabilizing agent described.

(8) The acid value of the resin composition obtained by mixing carboxylic anhydride with the fatty acid-modified aromatic epoxy resin is 1
The rust stabilizing agent according to the above (6) or (7), which is 0 to 100.

(9) On the surface of the steel material, the above (1) to (8)
A rust stabilizing method for steel material, comprising applying the rust stabilizing agent according to any one of the above and drying.

(10) A rust-stabilized steel material having a coating containing the following components (d) to (f) on its surface. (D) a resin having a negative fixed charge and having a conjugated double bond and a photodegradable functional group in the molecule, (e) a salt comprising an anion having a trapping and depositing action on iron ions and a counter cation, (f) ) 30 to 7 parts per 100 parts by weight of the coating
0 parts by weight pigment.

(11) The rust-stabilized steel according to (10), wherein the resin (d) is a resin having a phenyl group and / or a phenylene group in a molecule.

(12) The above (10) or (11), wherein the photodegradable functional group is an ester group.
The rust-stabilized steel material described in 1.

(13) The resin according to (10) to (12), wherein the resin (d) is a resin derived from a fatty acid-modified aromatic epoxy resin and carboxylic anhydride.
A rust-stabilized steel material according to any one of the above.

(14) The anion having a trapping and depositing action on the iron ion of the salt of (e) is phosphate ion and / or
Alternatively, the rust-stabilized steel material according to any one of the above (10) to (13), which is a molybdate ion.

[0024]

Embodiments of the present invention will be described below in detail.

(Applicable Steel) The steel to which the rust stabilizing agent of the present invention can be applied is not particularly limited. Although the effect is also recognized for ordinary steel, Cu, N
It is particularly effective for low alloy steels containing small amounts of alloying elements such as i, Cr, P, and Mo. Further, the treated surface is preferably in a state where scale and rust on the surface have been removed by blasting or the like, but this is not always necessary.

(Salt) In the present invention, the salt composed of an anion having a trapping and depositing action on iron ions contained in the treating agent and a counter cation reacts with iron ions generated by a corrosion reaction, and under certain conditions, A salt consisting of an anion and a counter cation capable of forming a deposited film. Examples of such anions include phosphate, chromate, beryllate, silicate, titanate, vanadate, manganate, selenate, zirconate, molybdate, tungstate. And the like.

Among them, the inclusion of a salt having a phosphate ion and / or a molybdate ion as an anion effectively prevents appearance deterioration due to flowing rust and the like in the rust stabilization process and efficiently stabilizes under the film. It is preferable because rust can be generated. Specific examples include zinc phosphate, aluminum phosphate, ammonium phosphate, calcium monohydrogen phosphate, cadmium phosphate, potassium phosphate, calcium phosphate, silver phosphate, chromium phosphate, cobalt phosphate, and mercury phosphate. , Sodium ammonium hydrogen phosphate,
Uranyl hydrogen phosphate, strontium hydrogen phosphate, diammonium hydrogen phosphate, dipotassium hydrogen phosphate, disilver hydrogen phosphate, disodium hydrogen phosphate, barium hydrogen phosphate, magnesium hydrogen phosphate, manganese hydrogen phosphate, phosphorus Cerium phosphate, thallium phosphate, iron phosphate, copper phosphate,
Thorium phosphate, sodium phosphate, lead phosphate, zinc dihydrogen phosphate, cadmium dihydrogen phosphate, ammonium dihydrogen phosphate, potassium dihydrogen phosphate, calcium dihydrogen phosphate, sodium dihydrogen phosphate, phosphoric acid Barium dihydrogen, manganese dihydrogen phosphate, lithium dihydrogen phosphate, nickel phosphate, barium phosphate, bismuth phosphate, magnesium phosphate, magnesium ammonium phosphate, manganese phosphate, lithium phosphate, sodium phosphotungstate, Sodium phosphomolybdate, aluminum phosphomolybdate, ammonium phosphomolybdate, aluminum dihydrogen tripolyphosphate, sodium molybdate, zinc molybdate, ammonium molybdate,
Potassium molybdate, calcium molybdate, lead molybdate and the like can be mentioned. In addition to these, other salts capable of capturing and depositing iron ions, such as chromate, vanadate and tungstate, can also be added.

These are preferably added as fine powder having an average particle diameter of 10 μm or less in order to improve the dispersion in the treating agent. Generally, commercially available pigments may be pulverized and added, or any pigment containing a component falling within the above range may be added as it is. The addition amount is preferably 1 to 10 parts by weight based on 100 parts by weight of the solid content of the treating agent. Below this range, the effect of maintaining good appearance is insufficient, and above this range, the strength of the film is insufficient, and the appearance is rather poor.

(Resin composition having negative fixed charge)
The resin composition having a negative fixed charge in the present invention refers to a resin composition in which the fixed charge in the processing agent is negative due to the action of the resin, pigment, and the like, and specifically, the resin in the processing agent. A resin composition having a carboxyl group, a sulfone group, a phosphoric acid group, a phenolic hydroxyl group, or the like as a functional group in the molecule of the component. Any type of base resin can be used as long as it is a resin having these functional groups and capable of forming a cured film of the treatment agent. Examples of the base resin include epoxy resin, phenol resin, polyester resin, and acrylic resin. It can be obtained by using one or more of polyurethane resin, fluorine resin, butyral resin, vinyl resin, alkyd resin, polysulfone humic acid, tannic acid, cation exchange resin, etc., as they are, or appropriately modified. .

Among them, an acid value having a free anionic functional group such as a carboxyl group and a sulfone group is particularly preferably 10 to 10.
A treating agent containing 100 resins is preferable because it has good resistance to flying salt. If the acid value is less than 10, flying salt resistance is inferior, and if it exceeds 100, stable rust forming performance is inferior.

The content of the resin having a free anionic functional group is preferably 20 to 50 parts by weight based on 100 parts by weight of the solid content of the treating agent, from the viewpoint of the balance between the film strength and the function of maintaining the appearance during the process of film deterioration. . As the type of resin having a free anionic functional group, a reaction product of a fatty acid-modified epoxy resin and carboxylic anhydride is most preferably used because of its excellent appearance retention performance and stable rust forming function.

(Resin Composition Containing Conjugated Double Bond) In the present invention, a resin composition having a conjugated double bond is a resin composition having a molecular skeleton in which a plurality of double bonds are present with a single bond interposed therebetween. Object, having a delocalized π electron cloud,
It easily absorbs ultraviolet light, visible light, and the like, and contributes to good weatherability due to deterioration from the surface layer of the film. Examples of the resin composition having such a conjugated double bond include aromatic hydrocarbons such as benzene, naphthalene, indene, tetralin, anthracene, and phenanthrene, furan, thiophene, pyrrole, pyran, thiopyran, pyridine, indole, quinoline, and purine. And the like, but an aliphatic polyene such as butadiene may be used. Among these,
In particular, those containing a phenyl group or a phenylene group containing a benzene ring are the most excellent in the appearance maintaining function of the treating agent of the present invention, and are preferably used. (Photo-degradable functional group) Further, the photo-degradable functional group contained in the resin composition of the present invention is mainly
Ish type, and functional groups capable of performing a Norrish type II photodisintegration reaction, ketones and esters are typical.In the present invention, those containing an ester group as a photodisintegratable functional group have a disintegration rate. Is moderate and preferable for the purpose of the present invention.

The resin composition having a conjugated double bond and a photo-degradable functional group and having a negative fixed charge includes:
Since the reaction product of the fatty acid-modified aromatic epoxy resin and carboxylic anhydride has moderate weathering properties and appearance-retaining function as a rust stabilizing agent, and is also excellent in flying salt resistance,
Particularly preferably used.

(Pigment) In the present invention, in addition to the above components, the pigment is contained in the range of 30 to 70 parts by weight in 100 parts by weight of the solid content of the treating agent. The pigment here means an inorganic pigment and an organic pigment which can be contained in a general treating agent.

In the present invention, at least one or more salts composed of an anion having a trapping and depositing action on iron ions and a counter cation and a resin composition having at least a resin composition having a negative fixed charge, having a solid content of 100% By setting the weight of the pigment in the range of 30 to 70 parts by weight in the weight part, stable rust is generated very efficiently in the process of forming stable rust under the treatment agent film, and under the film. In the process of forming rust on the film, blistering of the film and the effect that appearance abnormality such as peeling of the film in the form of a film is extremely unlikely to occur is found by the study of the present inventors. .

In this case, the weight part of the pigment is extremely important than the kind of the pigment. If the weight of the pigment in 100 parts by weight of the solid content of the treating agent is less than 30 parts by weight, blistering of the film or peeling of the film tends to occur, and stabilization of rust under the film is also slow. On the other hand, when the amount exceeds 70 parts by weight, the cohesive strength of the film decreases, and the stability of the film cannot be maintained.

The types of the pigments include organic pigments and inorganic pigments, and for the purpose of the present invention, inorganic pigments are preferred. Further, as inorganic pigments, barite, precipitated barium sulfate, chalk, precipitated calcium carbonate, chalk, clay, abrasive powder, talc, diatomaceous earth, silica white, alumina white, gypsum, satin white, gloss white, bentonite, calcium silicate , Precipitated magnesium carbonate, aluminum silicate, calcium lead oxide, titanium oxide, zinc oxide, lithobon, zinc sulfide, lead white, zircon oxide, antimony white, tin oxide, carbon black, oil smoke, graphite, iron black, zinc powder, Lead oxide, silicon carbide, red iron oxide, lead red, red, cadmium red, cadmium mercury red, molybdenum red, cuprous oxide, amber, graphite, zinc chromate, cadmium yellow, synthetic oka, titanium yellow, antimony yellow, barium yellow , Strontium yellow, chrome green, chromium oxide green, viridian, zinc green, cobalt green, d Lardo green, manganese green, Prussian blue, ultramarine blue, cobalt blue, cerulean blue, manganese blue, manganese violet, dark soy cobalt violet, pale mouth cobalt violet, Mars violet, aluminum powder, and the like.

Any of these pigments may be used as long as these pigments are appropriately combined and in a predetermined blending amount. In particular, the color of the treating agent film is preferably dark brown, which is similar to that of roughly stable rust. In particular, it is preferable to mix talc, red iron and black iron.

(Other Components) In addition to the above, the treating agent of the present invention includes a curing accelerator such as cobalt naphthenate and lead naphthenate, a thickener, other inorganic salts, a solvent, and a treating agent additive. Can be contained.

(Rust-stabilized steel) The rust-stabilized steel of the present invention has a hardened film of the above-mentioned rust-stabilizing agent formed on the surface of the steel, and the hardened film has a thickness of 10 to 100.
The range of μm is preferred. If it is less than this, the performance of the treating agent of the present invention is generally inferior, and if it is more than this, the effect is constant and the cost is high, so it is not preferable.

The rust stabilizing agent is preferably applied after the scale on the surface of the steel material is removed by sand blasting, shot blasting or the like to adjust the substrate, followed by drying. The base adjustment level is preferably St2 or higher for power tools and SIS Sa2 or higher for blasting. As a method for applying the rust stabilizing agent to the steel material surface, a method such as air spraying, airless spraying, or brushing can be applied as in the case of ordinary paints.

When the rust stabilization method of the present invention is applied to a steel structure, usually, after a steel structure unit is prepared,
Product blasting and painting in that state (rust stabilization treatment)
It can be done by touch-up after assembly on site. It is also possible to paint all on site. Further, the rust stabilization treatment of the present invention can be performed on an existing structure by adjusting the base material of the steel material surface.

[0043]

Embodiments of the present invention will be described below.

The weathering steel (SMA 4) specified in JIS G 3114
After blasting a test piece (150 mm × 70 mm × 6 mm), a treatment agent of a component system shown in Tables 1 to 3 was applied to a predetermined thickness. As the resin having a free anionic functional group mixed with the base resin, a carboxyl group-containing resin using a reaction product of castor oil-modified aromatic epoxy resin and hexahydrophthalic acid was used. The acid value was adjusted by variously changing the ratio of hexahydrophthalic acid to the aromatic epoxy resin. The compound having a conjugated double bond was mainly bisphenol A or phenol having a benzene ring, and a compound partially having a naphthalene ring was also used. The photodegradable functional group was basically an ester group.

As the coloring pigment, red iron oxide and iron black were mixed at a weight ratio of 1: 3. In addition, as components other than those described in Tables 1 to 3, 0.1 parts by weight of cobalt naphthenate as a curing accelerator, 0.1 parts by weight of lead naphthenate, and other additives for adjusting physical properties as a treating agent. Agents were added as appropriate. The parts by weight in Tables 1 to 3 are parts by weight in the cured coating film.

The weathering steels coated with these treating agents were evaluated by the following methods, and the performance of the weathering steels as rust stabilizing agents was evaluated.

(1) Existence of flowing rust, existence of stable rust formation, and appearance of coating film due to exposure in the countryside (3 years, exposure to 30 ° on the south side).

(2) Existence of flowing rust due to exposure to coastal area (3 years, exposure to 30 ° south side), existence of stable rust formation, and appearance of coating film.

(3) Flow rust, and appearance of coating film by accelerated test (salt spray test specified in JIS K-5400, one month).

The presence or absence of flowing rust: The presence or absence of flowing rust on the coating film surface was evaluated by appearance. ◎: not seen at all, ：: almost not seen, Δ: somewhat seen, × markedly seen

Formation of stable rust: The coating was peeled off and the state of rust under the coating was examined. ◎: Dense rust with few defects is continuously formed. ：: Dense rust is continuously formed, but slightly defective. ：: Rust is formed but lacks in density. , Many defects ×: Rust that is easily peeled off in layers

Appearance of coating film: It was examined whether blisters or film-like film peeling occurred on the coating film. ◎: No blistering or peeling was observed at all. ○: Either blistering or peeling was slightly observed.
Good in appearance Δ: Swelling and peeling were observed, and slightly poor appearance ×: Swelling and peeling were remarkably observed, and the appearance was extremely poor. The results are also shown in Tables 1 to 3.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

[Table 3]

Tables 1 to 3 show the following. The steel material of the invention example to which the rust stabilization treatment of the present invention is applied has a good appearance holding function and a stable rust forming function in both rural environments and coastal environments, and is also good in accelerated tests simulating severe environments. It has an excellent flow rust prevention function, and in any of the tests, the coating film has very few blisters and film-like peeling, and maintains a good appearance of the coating film.

In particular, by applying a phenylene group, a phenyl group-containing compound as a compound containing a conjugated double bond, and a resin composition containing an ester group as a photo-degradable functional group, an even better appearance is maintained.

Further, the resin composition having a negative fixed charge and having a conjugated double bond and photodisintegrability is a reaction product of a fatty acid-modified aromatic epoxy resin and carboxylic anhydride, so that a further product can be obtained. It has good appearance retention performance and stable rust forming function.

Further, by selecting an anion having a trapping and depositing action for iron ions from phosphate ions and / or molybdate ions, it is possible to achieve both better appearance maintaining function and more stable rust forming function.

Further, when the resin composition having a negative fixed charge has an acid value of 10 to 100, both excellent appearance maintaining function and stable rust forming function can be achieved.

[0061]

As described above, the steel material formed with the cured film of the rust stabilizing agent of the present invention has both flow rust prevention performance and efficient stable rust formation performance in both rural and marine environments. Thus, it was found that even in a very severe accelerated test, sufficient flow rust prevention performance, film blistering, and film-like peeling prevention effect were obtained.

By applying the rust stabilizing agent of the present invention to a weather-resistant steel material, maintenance of the steel material can be achieved while maintaining a good appearance, and the cost of repainting the conventional coating is not required. The economic effect is immense.

Continuing from the front page (72) Inventor Masahiro Takemura 1-2-1 Marunouchi, Chiyoda-ku, Tokyo F-term in Nihon Kokan Co., Ltd. (reference) 4J038 DB351 GA01 GA02 GA03 GA06 GA13 GA14 GA16 MA12 NA03 PB05 PB06 PC02 4K026 AA02 BA01 BA04 BA08 BB01 BB08 CA02 CA03 CA16 CA23 CA29 CA37 DA02 DA11 DA15 EA04

Claims (14)

[Claims] 1. A rust stabilizing agent for steel, comprising the following components (a) to (c): (A) a resin composition in which a compound having an anionic functional group, a compound having a conjugated double bond, and a compound having a photodegradable functional group are blended in a base resin; (C) a pigment in a proportion of 30 to 70 parts by weight per 100 parts by weight of the solid content of the rust stabilizing agent; 2. A rust stabilizing agent for steel, comprising the following components (a ′) to (c): (A ′) a resin composition in which a compound having a conjugated double bond and a compound having a photodegradable functional group are mixed with a resin having a negative fixed charge, and (b) an anion having a trapping and depositing action on iron ions. (C) 30 to 7 parts by weight per 100 parts by weight of the solid content of the rust stabilizing agent.
0 parts by weight pigment. 3. A rust stabilizing agent for a steel material comprising the following components (a ″) to (c): (a ″) a compound having an anionic functional group was blended into a base resin; A resin composition, wherein at least one of the base resin and the compound having an anionic functional group has an aromatic ring in a molecule, and the compound having the base resin and the anionic functional group. Are a resin or a resin composition having a functional group capable of reacting with each other to generate a photo-degradable functional group, (b) a salt composed of an anion having a trapping and depositing action on iron ions and a counter cation, c) 30 to 70 parts by weight of pigment per 100 parts by weight of solids of the rust stabilizing agent. 4. The rust stabilizing agent according to claim 1, wherein the compound having a conjugated double bond is a compound having a phenyl group and / or a phenylene group. 5. The compound having a photodegradable functional group,
The rust stabilizing agent according to any one of claims 1, 2, and 4, which is a compound having an ester group. 6. The rust stabilizing treatment according to claim 3, wherein the resin composition (a ″) is a resin composition obtained by mixing a carboxylic anhydride with a fatty acid-modified aromatic epoxy resin. Agent. 7. The method according to claim 1, wherein the anion having a trapping effect on the iron ion of the salt (b) is a phosphate ion and / or a molybdate ion.
7. The rust stabilizing agent according to 6. 8. The acid value of a resin composition obtained by blending a carboxylic anhydride with the fatty acid-modified aromatic epoxy resin is 10 to 10.
The rust stabilizing agent according to claim 6 or 7, wherein the rust stabilizing agent is 100. 9. A rust stabilizing method for a steel material, comprising applying the rust stabilizing agent according to any one of claims 1 to 8 to a surface of the steel material and drying. 10. A rust-stabilized steel material having a coating containing the following components (d) to (f) on its surface. (D) a resin having a negative fixed charge and having a conjugated double bond and a photodegradable functional group in the molecule, (e) a salt comprising an anion having a trapping and depositing action on iron ions and a counter cation, (f) ) 30 to 7 parts per 100 parts by weight of the coating
0 parts by weight pigment. 11. The rust-stabilized steel material according to claim 10, wherein the resin (d) is a resin having a phenyl group and / or a phenylene group in a molecule. 12. The rust-stabilized steel material according to claim 10, wherein the photo-degradable functional group is an ester group. 13. The rust stabilizer according to claim 10, wherein the resin (d) is a resin derived from a fatty acid-modified aromatic epoxy resin and carboxylic anhydride. Chemically treated steel. 14. The method according to claim 1, wherein the anion having a trapping effect on the iron ion of the salt of (e) is a phosphate ion and / or a molybdate ion.
The rust-stabilized steel material according to any one of 0 to 13.