JPS62109982A - Surface treatment of metal - Google Patents

Abstract

PURPOSE:To form a paint film fit for any service conditions by forming a zinc film on the surface of iron or an iron alloy by blasting, chromating the surface of the zinc film with a nonaqueous chromating soln. and applying an org. paint. CONSTITUTION:An aggregate of separated multilayered particles each obtd. by depositing zinc or a zinc alloy around an iron or iron alloy nucleus with an iron-zinc alloy layer in-between is used as a blasting material. The blasting material is projected on the surface of iron or an iron alloy to form a zinc film on the surface. The surface of the zinc film is chromated with a nonaqueous chromating soln. and an org. paint is applied to form a paint film.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a method for treating iron or iron alloys with high corrosion resistance and high adhesion. Specifically, the present invention relates to a method for anticorrosion treatment of metal surfaces, which comprises forming a zinc or zinc alloy coating on an iron or iron alloy surface, subjecting it to a non-aqueous chromate treatment, and then applying an organic or inorganic paint to form a coating.

l 匪五! In order to improve the adhesion of paint when painting precious metals,
It is well known to perform phosphate treatment as a surface treatment, and to perform electrogalvanizing, hot-dip galvanizing, or chrome rinsing to improve corrosion resistance. Phosphate treatment improves paint adhesion, but has little effect on corrosion resistance. Zinc plating improves corrosion resistance, but reduces paint adhesion. A chromium rinse may also be applied on top of the phosphate treatment to improve corrosion resistance, but this is generally done in the form of an aqueous solution, so
There is a problem of environmental pollution due to wastewater. There are also powder coating methods using a fluidized dipping method and so-called resin coating methods in which the object to be treated is heated in advance. In this case, if the substrate has been treated with phosphate or zinc plating, the treated film will be eroded by the preheating.
The adhesion of the paint film will be significantly reduced, and the corrosion resistance of the overall film will also be extremely deteriorated. Although there has been a strong desire among those skilled in the art for a surface treatment that improves these disadvantages, there has been no suitable surface treatment.

Relatively recently, the applicant and others have developed technology for zinc coating using special blasting and non-aqueous chromate treatment compatible with the zinc coating, and have conducted intensive research on the relationship between coatings created using these developed techniques and various types of coatings, and have investigated the relationship between the two. was found to have extremely good compatibility.

That is, particles made of iron or iron alloy as a core and zinc or zinc alloy coated around the core are projected onto a metal member to form a zinc coating film on the surface, and this film is coated with a non-aqueous coating. This method involves applying an organic or inorganic paint after chromate treatment.

According to this method, the zinc-coated film formed by projecting zinc or zinc alloy-coated iron or iron alloy particles firmly adheres to the metal member to form a film with voids, and at the same time provides some corrosion protection to the metal member. Show. Furthermore, by applying non-aqueous chromate treatment to this formed film,
It exhibits extremely high corrosion resistance. The composite film thus formed has extremely good compatibility with various paints due to its form and properties, and has excellent paint adhesion and overall paint film corrosion resistance. Furthermore, since the composite coating has extremely good heat resistance, it is extremely effective for paints that are baked at high temperatures and thermoplastic fluidized dip coatings that are coated after being heated to a high temperature in advance. The present inventors discovered that by combining these different technologies, unexpected high performance could be obtained as a base treatment for various coating systems, and that the various problems of the above-mentioned prior art could not be solved by this, and 1. Completed the present invention. I ended up letting it happen.

According to the invention, particles are made of an aggregate of independent multi-layered particles made of iron or iron alloy as a core and zinc or zinc alloy coated around the core through an iron-zinc alloy layer. A zinc coating film is formed on the surface of iron or iron alloy by projecting a blasting material of A method for surface treatment of iron or iron alloys is provided, which comprises applying an organic or inorganic paint to the surface to form a film.

As used herein, the term iron alloy means a material consisting essentially of iron, and also includes stainless steel I.

According to the method of the present invention, while retaining the advantages of the blast zinc coating method, corrosion resistance is dramatically improved through non-aqueous chromate treatment, and it becomes a coating base with extremely good adhesion to paint and excellent corrosion resistance. A coating system that meets the usage conditions is obtained.

A to Precept B The first treatment of the present invention, that is, the formation of a zinc or zinc alloy coating by projecting a blasting material consisting of an aggregate of independent multilayer particles coated with blasted zinc. This is the process of The blast material used in this blast zinc coating method has a weight ratio of iron and zinc in the aggregate of 10 to 10
95% and zinc in the range of 5 to 90%, and is manufactured by adding iron powder to molten zinc or heat-treating a mixture of zinc powder and iron powder. The size of the blasting material is such that it can pass through a 16-mesh sieve, and it is projected onto the surface of the object to be treated using a blasting machine.

Regarding the blast zinc coating method, please refer to Japanese Patent Application Laid-open No. 56-45.
372 in more detail.

The second treatment of the present invention, that is, the non-aqueous chromate treatment, consists mainly of a chromic acid compound, an organic solvent (mainly a halogenated hydrocarbon solvent), and alcohols as a solubilizer, and optionally a stabilizer and A chromate film is formed using a composition containing a reaction accelerator.
O-5288 (DuPont), JP 1984-3363 (Du Pont), JP 56-62970 (Tokuyama Soda), JP 55-97476 (Nippon Paint), JP 1983
-139679 (Nippon Paint), patent application 1982-15
No. 3028 (Japan Dacro Shamrock), etc.

The organic solvent used in the non-aqueous chromate treatment of the present invention is a halogenated hydrocarbon containing chlorine and/or fluorine having 1 to 2 carbon atoms, such as methylene chloride, trichloroethane, trichloroethylene, perchlorethylene, trichlorotrifluoroethane. , dichlorotetrafluoroethane, tetrachlorodifluoroethane, mixtures thereof, and the like can be suitably used.

The chromic acid compound used in the method of the present invention is most preferably a compound called chromic anhydride or chromium dioxide, which corresponds to the chemical formula Cry. The chromic anhydride is used at a concentration of 0.01 to 10 parts, preferably 0.1 to 5 parts, per 100 parts by weight (hereinafter simply referred to as parts) of the halogenated hydrocarbon solvent. If the amount of chromic anhydride is less than 000 parts, the rate of the chromate reaction will be slow, and if it is more than 10 parts, the decomposition of the halogenated hydrocarbon solvent and solubilizer will be significant, and normal film formation will not be possible. This results in a tendency for corrosion resistance to decrease.

The solubilizing agent used in the method of the present invention is a secondary solubilizing agent having 3 to 20 carbon atoms that is soluble in the halogenated hydrocarbon solvent.
or tertiary alcohol.

In general, secondary propatool, tertiary butanol, tertiary amyl alcohol, triphenyl carbinol, etc. are preferably used, but they can uniformly dissolve the components of the processing liquid of the present invention and can be used for a long time. Tertiary butanol and tertiary amyl alcohol are particularly preferred because they are stable. The solubilizing agent is required to be used in an amount of at least 1 part or more per 100 parts of the halogenated hydrocarbon solvent, and may be in an amount of 20 parts or more. The larger the amount of solubilizer is, the more chromic anhydride is dissolved. If the amount of solubilizing agent is less than 1 part, the solubilizing power will be insufficient and it will be difficult to dissolve the ingredients uniformly.It is possible to use 20 parts or more, but it may become flammable depending on the usage conditions. Sometimes,
It is preferable to set this point as the upper limit.

The stabilizers used in the method of the present invention are amines.

Many known compounds such as quinones, nitro, azo or azoxy aromatic compounds, thioureas, dienes, organic nitrites, zinc fluoride, zinc oxide, etc., but in the case of chlorinated fluorinated hydrocarbon solvents, stabilizers There is no need to use this method, which is advantageous in this respect. Examples of these compounds include N-nitrodiphenylamine, azoxybenzene, hydroquinone, diisobutylamine, pentadiene, amyl nitrite, and many others. These can be used alone or in combination of two or more, and the amount thereof is preferably 0.001 to 5 parts per 100 parts of the halogenated hydrocarbon solvent. Use of amounts outside this range will have little or no expected effect or will be wasteful beyond the limits of effectiveness.

The reaction accelerator used in the method of the present invention is hydrogen fluoride, organic acid, water, etc., and these compounds are used alone or in combination.
They may be used in combination of more than one species, or may not be used at all depending on the situation. The organic acid may be any organic acid having 1 to 20 carbon atoms as long as it is soluble in the mixture of the above components.

Examples of these include formic acid, acetic acid, lactic acid, oxalic acid, fumaric acid, maleic acid, malic acid, and the like. These reaction accelerators are used in an amount of 0.001 part or more per 100 parts of the halogenated hydrocarbon solvent, and in the case of hydrogen fluoride and organic acids, they can be used in an amount of 0.12 part or more. In the case of water, it is preferable to use it within a range that can maintain a uniformly dissolved system. If it is below these ranges, the effect cannot be expected, and if it is above it, defects such as significant corrosive effects on the objects to be treated and equipment or inability to maintain a homogeneous system will occur.

The chromate treatment liquid used in the method of the invention is substantially non-aqueous, the halogenated hydrocarbon solvent performs the task of degreasing and cleaning, makes the treatment liquid non-flammable, and the solubilizer uniformly dissolves all components. It is necessary that all components of the treatment liquid are dissolved uniformly; if they are not uniform, the coating will be formed unevenly and the corrosion resistance will deteriorate.

Regarding the first and second treatments of the method of the present invention, that is, the combination of the blast zinc coating method and the non-aqueous chromate treatment method, the patents (Japanese Patent Application No. 188,784, 1984) previously filed by the applicants of the present application, etc. Described in detail.

For the third treatment of the method of the present invention, that is, applying an organic or inorganic paint to the object to be treated, various commonly used coating methods are used.

As pretreatment for painting, it is sufficient to apply the above-mentioned blast zinc coating method and non-aqueous chromate treatment method, and if there is no particular contamination, painting can be carried out as is.

The paint used may be any type of paint, such as a solvent-based paint, a water-soluble paint, or a monochrome paint. Also.

As a coating method, any method currently practiced by those skilled in the art, such as dipping, brushing, electrostatic spraying, air spraying, electrodeposition, and fluidized dipping flow coating, can be used.

EXAMPLES The present invention will be illustrated in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

The test piece was a cold-rolled steel plate measuring 70 x 150 x 21. After degreasing by steam cleaning with trichloroethane, a blast zinc coating treatment was performed for 30 minutes by spraying the zinc or zinc alloy adhering blasting material on the surface of the test piece. 100
A zinc coating film was formed with a basis weight of 120 mg/dm2 to 120 mg/dm2, and then a non-aqueous chromate treatment was performed to form a chromate film on the surface of the test piece.

The obtained test pieces were coated with various coatings and subjected to performance tests.

Details of the performance test method are as described below.

(1) Baseline adhesion test (-substrate adhesion test) Based on the baseplate level test of Paint General Test Method @ (JIS K 5400). For the sample after 24 hours of painting, use a cutter knife to make 100 squares of 1 mm square on the paint film, then apply cellophane tape (18 mm width) by pressing firmly and attaching it at a 45 degree angle. Peel off by pulling strongly at an angle and evaluate adhesion based on the number of remaining base marks.

(2) Salt water spray test Based on JIS Z 2371 salt water spray test method. Continuous spraying of 5% saline at 35℃. A cut (cross cut) that reaches the iron base is made in advance on the coating film of the test piece using a cutter knife. After the test, evaluate the occurrence of blisters, peeling, and red rust on the undamaged flat surface, and the occurrence of blisters around the crosscut.

(3) Secondary adhesion test After completing the corrosion resistance test, conduct an adhesion test using cellophane tape after making base marks on the flat surface, or perform an adhesion test using cellophane tape at the cross-cut portion. Those with less peeling of the coating film are evaluated as having good corrosion resistance.

Example 1 In the preparation of the test specimen, following the blast zinc coating treatment,
For 100 parts of trichlorotrifluoroethane, t-
Butanol 15 parts, chromic anhydride 2 parts, oxalic acid 0.0
1 part uniformly dissolved in a processing solution containing 1 part at reflux temperature.
After soaking for a minute and steam cleaning, it was taken out and cooled to room temperature to perform non-aqueous chromate treatment, and the obtained test piece was painted with various paints to a film thickness of 20μ.
It was subjected to a performance test. The paints, coating conditions, and test results are shown in Table 1.

Comparative Example 1 As a representative example of conventional coating base treatment, various coatings were performed using the most commonly performed zinc phosphate treatment, and examples are shown in Table 1 as Comparative Example 1.

Example 2 Samples were prepared in the same manner as in Example 1, except that the composition of the non-aqueous chromate treatment liquid shown in Table 2 was used, and the results shown in Table 1 were obtained.

Example 3 In Example 1, an anionic electrodeposition paint and a cationic electrodeposition paint were used to coat a film with a thickness of 20 μm, and a performance test was conducted. The test results are shown in Table-3.

Comparative Example 2 In Example 3, instead of the paint base treatment according to the present invention, electrodeposition coating was performed using the most commonly performed zinc phosphate treatment as a representative example of the conventional paint base, and the performance test was conducted. provided. The test results are shown in Table-3.

Example 4 In Example 1, electrostatic coating was performed using an epoxy resin powder coating, baked at 200°C for 20 minutes, and a coating of 50μ
The film thickness was obtained. This sample was subjected to a performance test, and the results shown in Table 4 were obtained.

Comparative Example 3 In Example 4, a sample treated with zinc phosphate was used instead of the coating base according to the present invention, and the performance test results shown in Table 4 were obtained.

Example 5 In Example 1, coating was performed using a polyvinyl chloride resin powder coating by the fluidized dipping method. Preheating before immersing in the fluidized paint bath is performed by heating the specimen to 280°C in a preheating oven set at 350-400°C, and then immediately immersing it completely in the fluidized bed for a few seconds before pulling it out. After coating, heating was performed in a heating furnace set at 230 to 240°C. The film thickness was about 0.3 mm. This sample was subjected to a performance test, and the results shown in Table 4 were obtained.

Comparative Example 4 In Example 5, a similar coating was performed using a sample material (iron base) that had been subjected to rust removal by pickling and degreasing with trichlorethylene instead of the coating base according to the present invention, and this sample was subjected to a performance test. The results shown in Table 4 were obtained.

Comparative Example 5 In Comparative Example 5, a test piece treated with zinc phosphate was used instead of the sample material (iron base) and the same coating was applied, and this sample was subjected to a performance test, and the results shown in Table 4 were obtained. Ta.

Comparative Example 6 In Comparative Example 5, instead of the sample material (iron base), a test piece subjected to electrogalvanized yellow chromate treatment was used and painted in the same manner as in Comparative Example 5, and this sample was subjected to a performance test.
I got the result.

Procedural amendment December 10, 1985 Michibe Uga, Commissioner of the Patent Office Indication of the case 1985 Patent Immediately No. 249026 2 Name of the invention Metal surface treatment method 3 Person making the amendment Relationship to the matter Patent Applicant name Nippon Dacro Shamrock Dowa Iron Powder Industry Co., Ltd. 4 Agent (164) 5 Date of amendment order Voluntary 6 Number of inventions increased by amendment None 7 Subject of amendment Description (full text) Description 1. Name of the invention Metal surface treatment method 2. Claims Independent multi-layer particles made of iron or iron alloy as a core and zinc or zinc alloy coated around this core via an iron-zinc alloy layer. A zinc coating film is formed on the surface of iron or iron alloy by projecting a blasting material consisting of an aggregate of A surface treatment method for iron or iron alloys that involves applying an organic paint to form a film.

3. DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for treating iron or iron alloys with high corrosion resistance and high adhesion. Specifically, the present invention relates to a method for anticorrosion treatment of metal surfaces, which comprises forming a zinc or zinc alloy coating on an iron or iron alloy surface, subjecting it to a non-aqueous chromate treatment, and then applying an organic or inorganic paint to form a coating.

When painting metal, in order to improve the adhesion of the paint,
It is well known to perform phosphate treatment as a surface treatment, and to perform electrogalvanizing, hot-dip galvanizing, or chrome rinsing to improve corrosion resistance. Phosphate treatment improves paint adhesion, but has little effect on corrosion resistance. Zinc plating improves corrosion resistance, but reduces paint adhesion. A chromium rinse may also be applied on top of the phosphate treatment to improve corrosion resistance, but this is generally done in the form of an aqueous solution, so
There is a problem of environmental pollution due to wastewater. There are also powder coating coating methods using a fluidized dipping method and so-called resin coating methods in which the object to be treated is heated in advance. In this case, for those that have been subjected to surface treatment such as phosphate treatment or zinc plating, the treated film will be attacked by preheating, and the adhesion of the painted film will be significantly reduced, and the corrosion resistance of the overall film will also be extremely deteriorated. Although there has been a strong desire among those skilled in the art for a surface treatment that improves these disadvantages, there has been no suitable surface treatment.

Relatively recently, the applicant and others have developed technology for zinc coating using special blasting and non-aqueous chromate treatment compatible with the zinc coating, and have conducted intensive research on the relationship between coatings created using these developed techniques and various types of coatings, and have investigated the relationship between the two. was found to have extremely good compatibility.

That is, particles made of iron or iron alloy as a core and zinc or zinc alloy coated around the core are projected onto a metal member to form a zinc coating film on the surface, and this film is coated with a non-aqueous coating. This method involves applying an organic or inorganic paint after chromate treatment.

According to this method, the zinc-coated film formed by projecting zinc or zinc alloy-coated iron or iron alloy particles firmly adheres to the metal member to form a film with voids, and at the same time provides some corrosion protection to the metal member. or show. Furthermore, by applying non-aqueous chromate treatment to this formed film,
It exhibits extremely high corrosion resistance. The composite film thus formed has extremely good compatibility with various paints due to its form and properties, and has excellent paint adhesion and overall paint film corrosion resistance. Furthermore, since the composite coating has extremely good heat resistance, it is extremely effective for paints that are baked at high temperatures and thermoplastic fluidized dip coatings that are coated after being heated to a high temperature in advance. The present inventors have discovered that by combining these different technologies, unexpected high performance can be obtained as a base treatment for various coating systems, and that the various problems of the above-mentioned prior art can be solved thereby, and the present invention has been completed. reached.

That is, according to the present invention, a collection of independent multilayer particles made of iron or iron alloy as a core and zinc or zinc alloy coated around the core through an iron-zinc alloy layer. A zinc coating film is formed on the surface of iron or iron alloy by projecting a blasting material consisting of carbon dioxide onto the surface of iron or iron alloy (hereinafter referred to as the blast zinc coating method), and non-aqueous chromate is applied to the surface thus formed. A method of surface treatment of iron or iron alloy is provided, which comprises applying an organic paint to the surface to form a film after the treatment.

As used herein, the term iron alloy refers to a material consisting essentially of iron, and also includes stainless steel.

According to the method of the present invention, while retaining the advantages of the blast zinc coating method, corrosion resistance is dramatically improved through non-aqueous chromate treatment, and the adhesion with paint is extremely good, making it a highly corrosion-resistant coating base, which can be applied to any coating. A coating system that meets the usage conditions is obtained.

Detailed Description of the Invention The first process of the present invention, namely the blast zinc coating method, uses iron or an iron-zinc alloy as a core, and deposits zinc or zinc alloy around the core through an iron-zinc alloy layer. This is a process in which a zinc or zinc alloy coating is formed by projecting a blasting material consisting of an aggregate of independent multilayer particles. The blasting material used in this blasting zinc wave sonic method is one in which the weight ratio of iron and zinc in the aggregate ranges from 10 to 95% iron and 5 to 90% zinc, and iron powder is poured into molten zinc. or a method of heat treating a mixture of zinc powder and iron powder. The size of the blasting material is 16
This is enough to pass through a mesh sieve, and is blasted onto the surface of the object using a blasting machine. The blast zinc coating method is described in more detail in JP-A-56-45372.

The second treatment of the present invention, that is, the non-aqueous chromate treatment, consists mainly of a chromic acid compound, an organic solvent (mainly a halogenated hydrocarbon solvent), and an alcohol as a solubilizer, and optionally contains a stabilizer and A chromate film is formed using a composition containing a reaction accelerator.
O-5288 (DuPont), JP 1984-3363 (Du Pont), JP 56-62970 (Tokuyama Soda), JP 55-97476 (Nippon Paint), JP 1983
-139679 (Nippon Paint), patent application 1986-153
028 (Japan Dacro Shamrock), etc.

The organic solvent used in the non-aqueous chromate treatment of the present invention is a halogenated hydrocarbon containing chlorine and/or fluorine having 1 to 2 carbon atoms, such as methylene chloride, trichloroethane, trichloroethylene, perchlorethylene, trichlorotrifluoroethane. , dichlorotetrafluoroethane, tetrachlorodifluoroethane, mixtures thereof, and the like may be suitably used.

The chromic acid compound used in the method of the present invention is most preferably a compound called chromic anhydride or chromium dioxide, which corresponds to the chemical formula CrO3. The chromic anhydride is used in an amount of 0.01 to to parts, preferably 0.1 to 5 parts by weight, per 100 parts by weight of the halogenated hydrocarbon solvent (hereinafter simply referred to as parts).
Used at a concentration of 50%. If the amount of chromic anhydride is less than 0.01 part, the rate of chromate reaction will be slow and 10
If the amount is more than 100%, the decomposition of the halogenated hydrocarbon solvent and solubilizing agent in the bath will be significant, and a normal coating will not be formed, resulting in a tendency for corrosion resistance to decrease.

The solubilizing agent used in the method of the present invention is a secondary solubilizing agent having 3 to 20 carbon atoms that is soluble in the halogenated hydrocarbon solvent.
grade or tertiary R&alcohol.

In general, secondary propatool, tertiary butanol, tertiary amyl alcohol, triphenyl carbinol, etc. are preferably used, but they can uniformly dissolve the components of the processing liquid of the present invention and can be used for a long time. Tertiary butanol and tertiary amyl alcohol are particularly preferred because they are stable. The solubilizing agent is required to be used in an amount of at least 1 part or more per 100 parts of the halogenated hydrocarbon solvent, and may be in an amount of 20 parts or more. The larger the amount of solubilizer is, the more chromic anhydride is dissolved. If the amount of solubilizing agent is less than 1 part, the solubilizing power will be insufficient and it will be difficult to dissolve the ingredients uniformly.Although it is possible to use 20 parts or more, it may become flammable depending on the conditions of use. Therefore, it is preferable to set this as the upper limit.

The stabilizers used in the method of the present invention include many known compounds such as amines, quinones, nitro, azo or azoxy aromatic compounds, thioureas, dienes, organic nitrites, zinc fluoride, zinc oxide, etc. In the case of chlorinated fluorinated hydrocarbon solvents, there is no need to use a stabilizer, which is advantageous in this respect. Examples of these compounds include N-nitrodiphenylamine, azoxybenzene, hydroquinone, diisobutylamine, pentadiene, amyl nitrite, and many others. These can be used alone or in combination of two or more, and the amount thereof is preferably 0.001 to 5 parts per 100 parts of the halogenated hydrocarbon solvent. Use of amounts outside this range will have little or no expected effect or will be wasteful beyond the limits of effectiveness.

The reaction accelerator used in the method of the present invention is hydrogen fluoride, organic acid, water, etc., and these compounds are used alone or in combination.
They may be used in combination of more than one species, or may not be used at all depending on the situation. The organic acid may be any organic acid having 1 to 20 carbon atoms as long as it is soluble in the mixture of the above components.

Examples of these include formic acid, acetic acid, lactic acid, oxalic acid, fumaric acid, maleic acid, malic acid, and the like. These reaction accelerators are used in an amount of 0.001 part or more per 100 parts of the halogenated hydrocarbon solvent, and in the case of hydrogen fluoride and organic acids, they can be used in an amount of 0.12 part or more. In the case of water, it is preferable to use it within a range that can maintain a uniformly dissolved system. If it is below these ranges, the effect cannot be expected, and if it is above it, defects such as significant corrosive effects on the objects to be treated and equipment or inability to maintain a homogeneous system will occur.

The chromate treatment liquid used in the method of the invention is substantially non-aqueous, the halogenated hydrocarbon solvent performs the task of degreasing and cleaning, makes the treatment liquid non-flammable, and the solubilizer uniformly dissolves all components. It is necessary that all components of the treatment liquid are dissolved uniformly; if they are not uniform, the coating will be formed unevenly and the corrosion resistance will deteriorate.

Regarding the first and second treatments of the method of the present invention, that is, the combination of the blast zinc coating method and the non-aqueous chromate treatment method, there is a patent application previously filed by the applicant and others (Japanese Patent Application No.
-188784).

For the third treatment of the method of the present invention, that is, applying an organic or inorganic paint to the object to be treated, various commonly used coating methods are used.

As pretreatment for painting, it is sufficient to apply the above-mentioned blast zinc coating method and non-aqueous chromate treatment method, and if there is no particular contamination, painting can be carried out as is.

The paint used may be any type of paint, such as a solvent-based paint, a water-soluble paint, or a powder paint. Also.

Application methods include dipping, brushing, and electrostatic spraying.

Any method currently practiced by those skilled in the art can be used, such as air spray, electrodeposition, fluidized dipping, flow coating, etc.

DETAILED DESCRIPTION OF THE INVENTION The present invention will be illustrated in more detail by Examples and Comparative Examples, but the present invention is not limited thereto.

The test piece was a cold-rolled steel plate measuring 70 x 150 x 2 mm, and was degreased by steam cleaning with trichloroethane.
Blast zinc coating treatment was carried out for 30 minutes by spraying the zinc or zinc alloy coated blasting material, and the surface of the test piece was coated with 10
A zinc coating film is formed with a basis weight of 0 to 120 mg/dm2, and then a non-aqueous chromate treatment is applied to this to generate a chromate film on the surface of the test piece, and various coatings are applied to the obtained test piece to perform performance tests. Served. Details of the performance test method are as described below.

(1) Baseline adhesion test (-secondary adhesion test) Based on the baseplate level test of General Test Methods for Paints (JIS K 5400). For the sample 24 hours after painting, use a cutter knife to make 100 squares of 1o+m square on the paint film, and then apply cellophane tape (18mm width).
Apply strong pressure to stick it, pull it strongly at a 45 degree angle to peel it off, and evaluate the adhesion based on the number of remaining base marks.

(2) Salt water spray test Based on JIS Z 2371 salt water spray test method. Continuous spraying of 5% saline at 35℃. A cut (cross cut) that reaches the iron base is made in advance on the coating film of the test piece using a cutter knife. After the test, evaluate the occurrence of blisters, peeling, and red rust on the undamaged flat surface, and the occurrence of blisters around the crosscut.

(3) Secondary adhesion test After completing the corrosion resistance test, conduct an adhesion test using cellophane tape after making a base mark on the flat part, or perform an adhesion test with cellophane tape at the cross-cut part. Those with less peeling of the coating film are evaluated as having good corrosion resistance.

Example 1 In the preparation of the test specimen, following the blast zinc coating treatment,
For 100 parts of trichlorotrifluoroethane,
Butanol 15 parts, chromium anhydride M2 parts, oxalic acid 0.0
1 part uniformly dissolved in a processing solution containing 1 part at reflux temperature.
After soaking for a minute and steam cleaning, it was taken out and cooled to room temperature to perform non-aqueous chromate treatment, and the obtained test piece was painted with various paints to a film thickness of 20μ.
It was subjected to a performance test. The paints, coating conditions, and test results are shown in Table 1.

Comparative Example 1 As a representative example of conventional coating base treatment, various coatings were performed using the most commonly performed zinc phosphate treatment, and examples are shown in Table 1 as Comparative Example 1.

Example 2 Samples were prepared in the same manner as in Example 1, except that the composition of the non-aqueous chromate treatment liquid shown in Table 2 was used, and the results shown in Table 1 were obtained.

Example 3 In Example 1, an anionic electrodeposition paint and a cationic electrodeposition paint were used to form a film with a thickness of 20 μm.

It was subjected to a performance test. The test results are shown in Table-3.

Comparative Example 2 In Example 3, instead of the coating base treatment according to the present invention, electrodeposition coating was performed using the most commonly performed zinc phosphate treatment as a representative example of the conventional coating base, and the performance test was conducted. provided. The test results are shown in Table-3.

Example 4 In Example 1, electrostatic coating was performed using an epoxy resin powder coating, baking was performed at 200°C for 20 minutes, and a coating of 50μ
The film thickness was obtained. This sample was subjected to a performance test and the results shown in Table 1-4 were obtained.

Comparative Example 3 In Example 41, a sample treated with zinc phosphate was used instead of the coating base according to the present invention.

The performance test results shown in Table 4 were obtained.

Example 5 In Example 1, a polyvinyl chloride resin powder coating was applied by the fluidized dipping method. Preheating before immersing in the fluidized paint bath was performed by heating the test piece to 280°C in a preheating furnace set at 350 to 400°C, and then immediately immersing it completely in the fluidized bed for a few seconds and then pulling it out. Painted. Post-heating was performed in a heating furnace set at 230-240°C. The film thickness was about 0.3+nm. This sample was subjected to a performance test and the results shown in Table 1-4 were obtained.

Comparative Example 4 In Example 5, a similar coating was performed using a sample material (iron base) that had been subjected to rust removal by pickling and degreasing with trichlorethylene instead of the coating base according to the present invention, and this sample was subjected to a performance test. The results shown in Table 4 were obtained.

Comparative Example 5 In Comparative Example 4, a test piece treated with zinc phosphate was used instead of the sample material (iron base) and the same coating was applied, and this sample was subjected to a performance test and the results shown in Table 4 were obtained. Ta.

Comparative Example 6 In Comparative Example 1, instead of the sample material (iron base), a test piece subjected to electrogalvanized yellow chromate treatment was used and painted in the same manner as in Comparative Example 1, and this sample was subjected to a performance test.
A result of 4 was obtained.

Claims (1)

[Claims] A blasting material consisting of an aggregate of independent multilayer particles made of iron or iron alloy as a core and zinc or zinc alloy coated around this core through an iron-zinc alloy layer is applied to the surface of iron or iron alloy. It consists of forming a zinc coating film on the surface of iron or iron alloy by spraying, and then applying an organic paint to the substrate that has been subjected to non-aqueous chromate treatment to form a film. Surface treatment method for iron or iron alloys.