JPH01162780A - Zinc phosphate treatment of surface of metal for coating - Google Patents

Abstract

PURPOSE:To form a corrosion resistant chemical conversion film suitable for electrodeposition coating on the surface of metal by treating the surface of metal with an aq. soln. of acidic zinc phosphate treatment incorporating a specified amount of soluble tungsten compd. CONSTITUTION:After pretreating the surface of iron-base or/and zinc-base metal, it is immersed and treated in an acidic zinc phosphate treatment aq. soln. at 30-70 deg.C for about 15 seconds or more and then successively washed with city water and deionized water. At this time, this treatment liquid contains, as the main components, zinc ion in 0.1-2.0g/l, phosphate ion in 5-40g/l and soluble tungsten compd. in 0.05-20.0g/l expressed respectively in terms of tungsten. Further, at least one kind among 0.01-0.5g/l nitrite ion, 0.05-5g/l m- nitrobenzenesulfonate ion and 0.5-10g/l hydrogen peroxide (expressed in terms of H2O2 100%) is incorporated as an accelerator for film chemical conversion. Thereby, the film excellent in resistance to scab and resistance to hot salt water is formed.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a method for treating metal surfaces for painting with zinc phosphate, and more specifically, to improve the adhesion and corrosion resistance of coatings applied after electrocoating, especially cationic electrocoating. In particular, the present invention relates to a treatment method for forming a tungsten-containing zinc phosphate film having excellent warm salt water resistance and scabability.

BACKGROUND OF THE INVENTION Zinc phosphate coating annealing has been used for a long time as a metal pretreatment for painting, and spraying, dipping, or a combination thereof has been adopted as the treatment method. The spray method is advantageous in terms of equipment costs and production efficiency, but on the other hand, it has the disadvantages that it tends to leave untreated areas on complex items such as bags, and is prone to poor film formation due to spray splashing. There is. In addition, the immersion method has the disadvantage of requiring large equipment, but on the other hand, the spray treatment has the advantage of being able to form a uniform film even on areas where no film will be formed, even for complex articles with bag tlI structures. .

When forming a zinc phosphate film using the normal dipping method, the concentration of zinc ions in the treatment solution is as high as 2 to 4ζ/m, and the coating can only be formed at high temperatures (60 to 90°C) and for a long period of time (3 to 10 minutes). It could not be chemically formed, and the four films obtained had a film amount of at most (3 to 5+
/m2) and the quality of the film is poor, making it unsuitable as a base for painting, particularly as a base for electrodeposition coating, due to its poor adhesion, corrosion resistance, and appearance.

In addition, in recent years, the automobile sector and other industries require materials with sufficient rust prevention power in corrosive environments, so electrocoating paints are also changing from anionic to cationic paints, which cause shrinkage of the coating film during baking. Since a considerable amount of force is applied to the sub-41 phosphate film, the strength of the zinc phosphate film itself, which is the base for the cationic electrodeposition coating, must be strong. It was believed that it was not possible to obtain a suitable base for electrodeposition coating.

Under these circumstances, recently Japanese Patent Application Laid-Open No. 55-1077
No. 84 is coated with zinc ions, phosphate ions, nitrite ions, etc. in the treatment bath (by controlling the concentration of the arsenal accelerator, a low-temperature, short-time immersion method is used to produce a low coating amount, uniform and dense adhesion, A method for forming a zinc phosphate film with excellent corrosion resistance that can be used as a base for electrodeposition coating was proposed, and the dipping method suddenly came into the spotlight. In the Kaisho invention, zinc ions were added at 0.5-1.5 g/9, phosphate ions were added at 5-30 g/9, and nitrite ions were added at 0.01-0.
The metal surface was heated at 40 to 70°C for 15 to 12 g/sec with an acidic zinc phosphate treatment solution containing these as the main ingredients.
By immersion treatment for 0 seconds and then spray treatment for 2 to 60 seconds using the same treatment solution and treatment temperature as above for the purpose of removing slugs and dirt, a uniform and dense electrical coating with a low film amount of 1.5 to 3 g/m2 was obtained. It forms a base suitable for coating.

After that, steel materials plated with zinc or alloyed zinc on only one side began to be used as body materials mainly in the automobile industry for the purpose of further improving the corrosion resistance after painting, and although immersion treatment in the treatment bath described above poses no problem on iron-based surfaces, For zinc-based surfaces, there are problems such as insufficient salt spray resistance after cationic electrodeposition coating, and secondary adhesion after intermediate and top coatings that are significantly inferior to iron-based surfaces. Closer
・In order to deal with this, for example, Japanese Patent Application Laid-open No. 1987-
No. 152472, 0.6 to 3 g/J of manganese ions and/or 0.6 g/J of nickel ions are added to a bath with controlled concentrations of zinc ions, phosphate ions, and film formation promoters.
Technology to contain 1 to 4 g/l or 0.0 fluorine ion together with manganese ion for the purpose of lowering the processing temperature.
Technology to add 5g/R or more (Special Publication No. 61-36588
) has been developed.

In this way, it is possible to provide a chemical conversion film suitable for electrodeposition coating on iron-based surfaces, or on metal surfaces that have both an iron-based surface and a zinc-based surface, by zinc phosphate treatment using the dipping method. It is now possible to immerse a wide range of products, including not only building materials and small items, but also car bodies and parts, in zinc phosphate chemical conversion treatment, which is aimed at improving the corrosion resistance of a wide range of items with iron, zinc, and their alloy surfaces. The law has come to establish a determined tyranny. However, in recent years, the quality requirements for corrosion resistance of automobile bodies have become more and more sophisticated. There are strong demands for prevention of corrosion (corrosion) and higher resistance to warm salt water, and the current zinc phosphate treatment methods are becoming unable to meet these demands.

On the other hand, spray treatment is still the mainstream for steel furniture, etc., but even in this field, galvanized steel sheets are being introduced for the purpose of improving rust prevention, and the adhesion and corrosion resistance of these sheets are not always satisfactory. Not yet.

Furthermore, it is desired to improve scab resistance and hot salt water resistance through pretreatment.

Problems to be Solved by the Invention Therefore, a method for treating a metal surface with iron surface or a combination of iron and zinc surfaces with zinc phosphate, which can provide a corrosion-resistant chemical conversion film suitable for painting, especially electrodeposition coating, is proposed. In addition, the scab resistance of steel surfaces and the hot salt water resistance of iron and zinc surfaces are significantly improved, and the secondary adhesion when applying intermediate and top coats to electrodeposited boards is also further improved. There is a need for a processing method, and it is an object of the present invention to meet this problem.

Means for Solving the Problems According to the present invention, the above object is achieved by forming a metal surface with a tungsten compound of 0.05 to 20.0
This is achieved by a method for treating metal surfaces with zinc phosphate, which is characterized in that the metal surface is treated with an acidic zinc phosphate treatment aqueous solution containing g/l. The present invention is most effective when targeting an iron-based surface or a metal surface having a combination of an iron-based surface and a zinc-based surface, but is not limited to this, and the same purpose can be applied to a zinc-based surface alone. Needless to say, it can be handled with ease. That is, the present invention targets metal surfaces of any of the above embodiments.

An example of a tree that is practically advantageous for the treatment method of the present invention is as follows. First, treat the metal surface with an alkaline degreaser at temperature 3.
0 to 6 [Degrease by spraying and/or dipping at 1°C for 2 minutes, then washing with tap water, and then spraying and/or dipping with a surface conditioner for 10 to 30 seconds at room temperature in the case of dipping. Then, it may be immersed and sprayed in the above-mentioned acidic zinc phosphate treatment aqueous solution of the present invention at a temperature of 30 to 70° C. for 15 seconds or more, and then washed with tap water and deionized water.

When the present invention is used in immersion treatment, the amount of zinc ion, which is the main component of the treatment liquid of the present invention, may be 0.1 to 2.0 g/J2, preferably Oj to 1.5 g/A. If O is less than 1 g/1, a uniform zinc phosphate film will not be formed on the iron-based surface, and a partially blue-colored film with many ridges will be formed. Also 2
, (If it exceeds Ig/l, a uniform zinc phosphate film will be formed, but the film on the surface tends to be a film that is easily dissolved in alkali, and in particular, the film is easily dissolved by the alkaline atmosphere exposed during cationic electrodeposition. As a result, the resistance to hot salt water generally decreases, and the scab resistance is particularly poor in the case of iron-based surfaces.
It is not suitable for use as a base for electrodeposition coatings, especially cationic electrodeposition coatings, because the desired properties such as scorching cannot be obtained. Phosphate ion is 5 to 40g/, preferably 10 to 30g/ρ
It is. If it is less than 5 g/p, a non-uniform film is likely to be formed, and if it exceeds 40 g/p, no effect greater than that of the present invention can be expected, and the amount of chemicals used increases, which is economically disadvantageous. Soluble tungsten compound is 0.05~ as tungsten
20.0g/J, preferably 0.05~IO,ogJ
.

More preferably 0.1 to 3.0 g/Jl. 0.
If the amount is less than 0.05 g/l, the modification of the zinc phosphate film is insufficient, and the scab resistance and hot salt water resistance are not improved. On the other hand, 20
If it exceeds gA2, the amount of tungsten will be more than it contributes to the film reaction, and no effect greater than that of the present invention can be expected, and the amount of sludge will increase, which is not preferable.

As a film formation accelerator, nitrite ion 0. O1~0.
5 g/, 2, preferably 0.01 to 11.4 g/
l, TO-nitrobenzenesulfonic acid ion 0.05
~'5g/0. Preferably 0.1 to 4 g/l and hydrogen peroxide (calculated as 100% H2O2) 0.5 to 10 g/l,
Preferably, at least one type selected from 1 to 8 g/l may be used. If these accelerators do not reach a specified amount, sufficient film formation cannot be achieved on the iron-based surface, resulting in yellowing, and if the amount exceeds the specified amount, a blue-collar uneven film tends to be formed on the iron-based surface.

As sources of these main components, for example, zinc ions can be zinc oxide, zinc carbonate, zinc nitrate, etc., phosphate ions can be phosphoric acid, zinc phosphate, mankan phosphate, etc., and soluble tungsten compounds can be sodium tungstate, sodium tungstate, etc. Ammonium tungstate may be used, and the film formation accelerator may be sodium nitrite, ammonium nitrite, sodium m-nitrobenzenesulfonate, hydrogen peroxide solution, or the like.

In addition, in the case of spray treatment, it improves the conversion of the zinc phosphate film for the paint base onto the metal surface, reduces nitrite consumption to 172 or less compared to conventional treatment solutions, and improves by-product sludge. 173～
For the purpose of reducing the concentration to 1/4, the phosphate ion concentration in the treatment solution during chemical conversion treatment is at least 5 g/, 1, the nitrite ion concentration is at least 0.02 to 0.5 g/ill, and the zinc ion concentration is at least Qjg/. p) I of the treatment liquid by maintaining the molar weight ratio of phosphate ions: nitrate ions to 1:07 to 1.3 and the molar ratio of phosphate ions:zinc ions to 1:0.116 or less. For example, according to Japanese Patent Publication No. 55-55,
No. 90 proposed and attracting attention, in accordance with the present invention, a soluble tungsten compound of at least 0.05 to 20 g/as tungsten is added to such a treatment agent, and also to a normal zinc phosphate treatment solution for spraying. By containing it in the above concentration range, it is possible to significantly improve scab resistance, hot salt water resistance, adhesion, especially adhesion to zinc-based surfaces, as well as the desired effects.

In addition to the above main components, the treatment liquid of the present invention may also contain manganese ions, nickel ions, fluorine ions, nitrate ions, chlorate ions, and the like. manganese ion,
2...7 Kelion is 0. Ig/f1 or higher is sufficient;
The sodium ion is 0 to 4 g/9, preferably o, i to 2
．． 0 g/J, nitrate ions from 0 to 15 g/A, preferably 2 to IOg/, (chlorate ions from 0 to 2.0 g/J, preferably 0.2 to 1.5 g/, Q) These components may be contained alone or in combination of two or more.As sources of these components, for example, manganese ions may be manganese carbonate, manganese nitrate, manganese chloride, manganese phosphate, etc., and nickel ions may be used. In this case, nickel carbonate, nickel nitrate, nickel chloride, nickel phosphate, nickel hydroxide, etc. may be used, the fluorine ion may be hydrofluoric acid, hydrofluoroboric acid, hydrofluorosilicic acid, or their metal salts, etc., and the nitrate ion may be sodium nitrate. , ammonium nitrate, zinc nitrate, manganese nitrate, nickel nitrate, etc., and the chlorate ion may be sodium chlorate, ammonium chlorate, etc.

The treatment temperature using the treatment liquid of the present invention may be 30 to 70°C, preferably 35 to 60°C. If the temperature is too low, the film formation properties will be poor and a long treatment time will be required. If the temperature is too high, the balance of the treatment solution is likely to be lost due to the decomposition of the coating 1 arsenal accelerator and the occurrence of precipitation in the treatment solution, making it difficult to obtain a good coating.

The treatment time may be 15 seconds or more, preferably 30 to 120 seconds. If the time is too short, a film having the desired crystals will not be sufficiently formed. In addition, when treating an article with a complicated shape such as an automobile body, it is practically preferable to combine immersion treatment and spray treatment. , then spray treatment for 2 seconds or more, preferably 5 to 45 seconds. Incidentally, in order to wash off the slurry and dirt that adhered during the immersion treatment, it is preferable that the spray treatment last as long as possible. Therefore, the treatment according to the present invention includes treatment modes such as dipping treatment, spray treatment, and combinations thereof.

The present invention also relates to a concentrated processing agent that provides a processing liquid having the above-mentioned composition. In this concentrated treatment agent, the weight of the zinc ion source and the phosphate ion source is in ionic form, and the soluble tungsten compound source is the weight of tungsten, and the weight ratio is zinc ion diphosphate ion: soluble tungsten. Compound (as W) = 1:2.5
~400; It is composed of two liquids, liquid (A) prepared by mixing to give a concentration of 0.025 to 200, and (B)m, which is an accelerator liquid. By diluting these and mixing them appropriately, the A processing solution having the same composition can be easily prepared. In addition, other ion sources other than the main component, such as manganese ions, nickel ions, fluorine ions, nitrate ions, and chlorate ions, can be added to the solution (A). However, the chlorate ion source is liquid (A) and may be added to liquid (B). In particular, when a manganese ion supply source is added to liquid (A), the chlorate ion source is added to (B) M. It is preferable to do so. In addition, the soluble tungsten compound source is mixed with the zinc ion source so that the ratio of zinc ion to tungsten compound is 1:0°025 to 200 by weight as tungsten and added to the solution (B). You can.

In addition, regarding the tungsten-containing zinc phosphate film obtained by treating the metal surface with the above-mentioned treatment agent and treatment conditions, if it contains 0.1 weight 5!6 or more of tungsten, this invention does not apply. It has been confirmed that it is effective.

According to the present invention having the above configuration, a coating base, especially an electrodeposition coating base, especially a cationic electrodeposition coating, can be applied to not only an iron-based surface but also a metal surface having both a zinc-based surface and an iron-based surface at the same time. As a base, it has excellent corrosion resistance, especially scab resistance, and forms a film that exhibits sufficient hot and salt water resistance and adhesion on all types of surfaces, including zinc-based surfaces, iron-based surfaces, and metal surfaces that contain zinc and iron at the same time. can do.

The present invention will be explained below with reference to Examples.

Examples 1 to 7, Example 10 and Comparative Examples 1 to 7 (1) Metals to be treated: (a) Alloyed molten zinc: Alloyed molten galvanized steel sheet (b) Electrolytic zinc: electrolytic galvanized steel sheet (c) Alloy Electrolytic zinc alloying: Alloyed electrogalvanized steel sheet (d) Cold rolled steel sheet (2) Acidic zinc phosphate treatment aqueous solution: 15 types having the composition shown in Table 1 were used (3) Treatment process The metal surfaces of 1) (a) to 2)) are treated simultaneously according to the following steps.

(4) Each treatment condition (a) Degreasing; Alkaline degreaser (manufactured by Nippon Paint Co., Ltd. [Ridrin 5D2
50,. 2% concentration by weight) and immersion treatment at 40°C for 2 minutes.

(b) Washing with water: Rinse with tap water for 15 seconds at room temperature.

(C) Surface conditioning: Surface conditioning agent (“Fixodin 5N-5” manufactured by Nippon Paint Co., Ltd.)
4, 0, 1 wt% concentration) and immersion treatment for 15 seconds at room temperature.

(d) Chemical formation: Using the above acidic zinc phosphate treatment aqueous solution, immersion treatment is performed for 120 seconds at the temperature shown in Table 1 (52°C or 40°C).

(e) Washing with water: Rinse with tap water for 15 seconds at room temperature.

(f) Pure water washing: Dip in ion-exchanged water for 15 seconds at room temperature.

(g) Drying: Dry with hot air at 100°C for 10 minutes. Incidentally, the appearance and weight of the chemical conversion film of the chemical conversion treated plate thus obtained were measured.

(h) Painting: Cationic electrodeposition paint (manufactured by Nippon Paint Co., Ltd., “Powert
Bake 1 inch of "Tsuburo 80 Gray") to a dry film thickness of 20 μm. Voltage: 180 V, energizing time: 3 minutes), 180°C.
Bake for 30 minutes. A portion of the electrodeposited plate obtained is subjected to a warm salt water immersion test. An intermediate coating ("Olga TO4811 Gray" manufactured by Nippon Paint Co., Ltd., melamine alkyd resin system) was spray-coated on the remaining electrodeposited plate to a dry film thickness of 30 μm, and baked at 140° C. for 20 minutes.

Next, top coat paint (Olga TO630 manufactured by Nippon Paint Co., Ltd.
Doper White, melamine alkyd resin) was spray-painted to a baked dry film thickness of 40μ at 140℃.
Bake for 20 minutes to obtain a painted board with 3 coats and 3 bakes in total. This is subjected to an adhesion test and a scab test.

Example 8.9 and Comparative Example 8.9 (1) Metals to be treated: (a) Alloyed hot-dip galvanized steel sheet (+
7> Electrolytic zinc: Electrolytic galvanized steel sheet (c) Alloyed electrolytic zinc; Alloyed electrolytic galvanized steel sheet (d) Cold rolled steel sheet (2) Acidic zinc phosphate treatment aqueous solution: 4 types having the composition shown in Table 1 (3) Treatment process The four types of metal surfaces ((1) (a) to (d)) are treated simultaneously according to the following steps.

(a) Degreasing: Alkaline degreaser (manufactured by Nippon Paint Co., Ltd. [Ridrin 510
2. +, 2% concentration by weight) for 2 minutes at 7°C.

(b) Water washing: Use tap water and wash with water for 15 seconds at room temperature. (C) Chemical formation: Use the above acidic zinc phosphate treated aqueous solution and spray pressure 0.
．． Spray at 7 kg,/cm 2 at 55° C. for 120 seconds.

(d) Washing with water: Rinse with tap water for 15 seconds at room temperature.

(e) Pure water washing: Dip in ion-exchanged water for 15 seconds at room temperature.

(f) Drying: Dry with hot air at +00°C for 10 minutes. Incidentally, the appearance and weight of the chemical conversion film of the chemical conversion treated plate thus obtained were measured.

(g) Painting: Apply cationic electrodeposition paint (manufactured by Nippon Paint Co., Ltd., "Power Top U-80 Gray") to a dry film thickness of 20 μm (voltage: 180 cm, current application time: 3 minutes) at 180°C.
Bake for 0 minutes. A portion of the electrodeposited plate obtained is subjected to a warm salt water immersion test. An intermediate coating ("Olga TO4811 Gray" manufactured by Nippon Paint Co., Ltd., melamine alkyd resin system) was spray-coated on the remaining electrodeposited plate to a dry film thickness of 30 μm, and baked at 140° C. for 20 minutes. Next, a top coat (Olga TO630 Doper White manufactured by Nippon Paint Co., Ltd., melamine alkyd resin system) is baked to a dry film thickness of 40 mm.
Spray paint the plate so that it is μ and bake it for 20 minutes at 140°C to obtain a coated board with 3 coats and 3 bakes. This is subjected to an adhesion test and a scab test.

Test Results: Various tests were conducted on the various test plates obtained in the above Examples and Comparative Examples, and the results are shown in Table 2. still,
Each test method is shown below.

(＾〉Warm salt water immersion test Apply force and tension with a sharp cutter to the electrodeposition coated plate, 5%
After 480 hours of immersion in saline solution at 55° C., an adhesive tape is attached to the cut portion and then peeled off, and the maximum peeling of the coating film is measured.

<8) Adhesion test: After soaking the painted board in deionized water at 40°C for 20 days, it was coated with grids (100 pieces) with 1 and 21111 spacing.
The number of rough coatings remaining on the painted board was counted by cutting a sharp strip using a sharp cutter and applying adhesive tape to each side of the strip.

(C) Scab test A cut was made on the painted board with a sharp cutter, and then the painted board was subjected to a 5% salt spray test (JIS-Z-2371, 24
time) → Humidity test (temperature 40℃, relative humidity 85%, 12
0 hours)→Indoor discharge N (24 hours) is considered as 1 cycle.
It was subjected to a 0-cycle corrosion test (hereinafter referred to as a scab test). The maximum number of paint film abnormalities (thread rust, blisters, etc.) on the painted surface after the test was investigated.

(Left below) Procedural amendment (voluntary) 1. Display of the case 1986 Patent Application No. 321737 2 Title of the invention Method for treating zinc phosphate on metal surfaces for painting 3 Person making the amendment Relationship to the case Patent applicant address 2-1 Oyodokita, Oyodo-ku, Osaka City No. 2 Name: Nippon Paint Co., Ltd. Representative: Yu Sasaki 4, Agent address: 6th floor, River Center Building, 3-57 Kyobashi, Higashi-ku, Osaka 540 (voluntary) 7. Subject of amendment: Claims in the specification Column and Detailed Description of the Invention Column 8 Contents of the Amendment As per Attachment 1, the claims are amended as follows: ``(1) The metal surface is 0.05 to 20.Og & A method for treating a metal surface with zinc phosphate, the method comprising treating a metal surface with an acidic zinc phosphate treatment hydroxide solution.

(2) 1lKH surface zinc ion 70.1-2.0g/j
l! , phosphate ion 5-40g/i, soluble tungsten compound as tungsten 0.05-2o, Og/i
The method according to claim 1, characterized in that the treatment is carried out with an acidic zinc phosphate treatment aqueous solution containing L and a film formation accelerator as main components.

(3) The method according to claim 2, wherein the treatment method is immersion treatment.

(4) Film formation accelerator contains nitrite ion 0. O1~0.5
g/jl! ,, m-nitrobenzenesulfonic acid ion 0
．． 05-5g/l and hydrogen peroxide 0.5-IOg/i
! The method according to claim 2, wherein at least one of the following is used.

(5) The method according to claim 2, wherein the acidic zinc phosphate treated aqueous solution contains mankan ions up to 3 g/L.

(6) The method according to claim 5, wherein the acidic zinc phosphate treatment aqueous solution contains up to 4 g/required of F...I ions.

(7) The method according to claim 5, wherein the acidic zinc phosphate treatment aqueous solution contains up to 4 gzZ of di...I Kel ions.

(8) Acidic zinc phosphate treated aqueous solution contains 15 g of nitrate ions
, /i or less and/or 2 g of chlorate ions, method (9) according to claim 2, wherein the treatment temperature is 30 to 70°C, ( 4. The method of claim 3, wherein the dipping treatment comprises a combination of first dipping for 15 seconds or more and then spraying.

(II) Method 5 (12) Zinc ion source according to claim 2, wherein the metal surface has an iron-based surface, a zinc-based surface, a ferrous surface, or an iron-based surface and a dumbbell-based surface at the same time. Acid ion source and tungsten ion source (as W)
The acidic zinc phosphate treated aqueous solution of item 2 above, consisting of component (A) containing 1:2.5 to 400:0.025 to 200 and component (B) containing a film formation accelerator. A two-part concentrated processing agent that can be adjusted by dilution.

(13) Two-component concentrated processing agent (14) in which W is added to (B)
) Zinc ion 0.1-2.0 gL, phosphate ion 5
- No. 40 ρ, tungsten-containing phosphorus obtained by treating with an acidic zinc phosphate treatment aqueous solution containing 0.05 to 20,0 g/L of soluble tungsten ion f arsenide as tungsten and a film formation accelerator as a main component. Metal material with acid zinc coating.

(15) The metal material according to claim 14, wherein the tungsten content of the tungsten-containing zinc phosphate film is 0.1% by weight or more. 2. On page 16 of the specification, lines 2 to 4, it says, ``Add the above zinc ion: tungsten...mixture to liquid B.'' .00
Add it to solution (B) so that it has a concentration of 25 to 200.''

3. "Chemical coating weight" in lines 5-4 from the bottom of page 18 of the specification A certain thing r Chemical conversion coating weight j to correct,

Claims (15)

[Claims] (1) A method for treating a metal surface with zinc phosphate, which comprises treating the metal surface with an acidic zinc phosphate treatment aqueous solution containing a soluble tungsten compound of 0.05 to 20.0 g/l of tungsten. (2) The main components of the metal surface are zinc ions of 0.1 to 2.0 g/l, phosphate ions of 5 to 40 g/l, soluble tungsten compounds of 0.05 to 20.0 g/l of tungsten, and a film formation accelerator. Claim 1, characterized in that the treatment is performed with an acidic zinc phosphate treatment aqueous solution containing
The method described in section. (3) The method according to claim 2, wherein the treatment method is immersion treatment. (4) Film formation accelerator is nitrite ion 0.01-0.5
g/l, m-nitrobenzenesulfonic acid ion 0.05
5 g/l and at least one selected from hydrogen peroxide 0.5 to 10 g/l, the method according to claim 2, (5) The method according to claim 2, wherein the acidic zinc phosphate treated aqueous solution contains manganese ions up to 3 g/l. (6) The method according to claim 5, wherein the acidic zinc phosphate treatment aqueous solution contains fluorine ions up to 4 g/l. (7) The method according to claim 5, wherein the acidic zinc phosphate treatment aqueous solution contains nickel ions up to 4 g/l. (8) Acidic zinc phosphate treated aqueous solution contains 15 g of nitrate ions/
1 and/or less than 2 g/l of chlorate ions. (9) The method according to claim 1, wherein the treatment temperature is 30 to 70°C. (10) The method according to claim 3, wherein the dipping treatment comprises a combination of first dipping treatment for 15 seconds or more and then spraying treatment. (11) Claim 2 in which the metal surface has an iron-based surface or an iron-based surface and a zinc-based surface at the same time.
The method described in section. (12) Zinc ion source, phosphate ion source and tungsten ion source (as W) in a ratio of 1:2.5 to 400:0.
A two-component concentrated solution for preparing by dilution the acidic zinc phosphate treatment aqueous solution of item 2 above, which consists of component (A) contained in a weight ratio of 0.025 to 200 and component (B) containing a film formation accelerator. Processing agent. (13) A two-component concentrated processing agent in which W is added to (B). (14) Contains zinc ion 0.1 to 2.0 g/l, phosphate ion 5 to 40 g/l, soluble tungsten ion compound as tungsten 0.05 to 20.0 g/l, and film formation accelerator as main components. A metal material having a tungsten-containing zinc phosphate film obtained by treatment with an acidic zinc phosphate treatment solution. (15) Claim 14, wherein the tungsten content of the tungsten-containing zinc phosphate coating is 0.1% by weight or more.
Metal materials listed in section.