GB2097429A - Process and composition for treating phosphated metal surfaces - Google Patents

Process and composition for treating phosphated metal surfaces Download PDF

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Publication number
GB2097429A
GB2097429A GB8208993A GB8208993A GB2097429A GB 2097429 A GB2097429 A GB 2097429A GB 8208993 A GB8208993 A GB 8208993A GB 8208993 A GB8208993 A GB 8208993A GB 2097429 A GB2097429 A GB 2097429A
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process according
ion
phosphate
film
zinc
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Nippon Paint Co Ltd
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Nippon Paint Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C22/00Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/82After-treatment
    • C23C22/83Chemical after-treatment

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  • Chemical & Material Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Treatment Of Metals (AREA)

Description

1
GB 2 097 429 A 1
SPECIFICATION
Process and composition for treating phosphated metal surfaces
An increasingly used commercial process for the application of siccative coatings to metal surfaces (e.g. iron-based or zinc-based surfaces) is the process of electrocoating, especially cationic 5 electrocoating. Various pretreating processes are known, including the application of a phosphate coating to the metal surface followed by treatment of the phosphated surface with a solution which does not contain chromium, and which accordingly is pollution-free, to improve the corrosion resistance of the metal surface. For example, Japanese Patent Publication No. 5622/1978 uses an aqueous solution of phytic acid to treat the phosphated surface, and Japanese Patent Publication No. 10 21971/1977 uses an aqueous solution of zirconium compound for this purpose. Both techniques have disadvantages. In the former technique, unless the surface of the metal which has been subjected to phosphating and is suitable for cationic electrocoating is sufficiently washed with pure water in a final water washing process after such treatment, pitting occurs in the electrocoated film and the appearance of the film is markedly inferior. Also, zinc-based metal surfaces show inferior results compared to iron-1 5 based surfaces with respect to adhesion and corrosion resistance of the coating film produced by cationic electrocoating.
In the latter technique, the stability of the aqueous solution of zirconium compound is unsatisfactory, and, especially in the neutral zone, there is a strong tendency for the zirconium compound to be hydrolyzed, so that it is difficult to maintain the required concentration of this 20 compound in the solution. In order to try to enhance the stability of the zirconium solution, the technique proposes the use of complexing agents such as gluconic acid and citric acid. However, in such instances there is a tendency for corrosive substances to remain on the treated metal surface, so that excessive water washing is required in the following final water washing step. Furthermore, here too, zinc-based surfaces so treated are inferior to iron-based surfaces so treated in adhesion and corrosion 25 resistance of the coating film.
The present invention relates to an improved process for treating a metal surface, especially for subsequent cationic electrocoating. The process results in improved adhesion and corrosion resistance of the coating film deposited by cationic electrocoating.
Accordingly, the invention provides a process for treating a metal surface having a phosphate 30 conversion coating, which process comprises treating said coated surface with an aqueous solution containing:
(a) at least 0.05 g/l (as Zr02) of water-soluble fluorozirconium compound; and
(b) at least 0.05 g/l of myo-inositol phosphate and/or water-soluble salt thereof;
the aqueous solution having a pH in the range 3 to 7, and the molar ratio of (a) to (b) being in the range 35 1:1 to 50:1.
The invention also provides a composition for treating a metal surface having a phosphate conversion coating, which composition is this aqueous solution.
When the metal surface is to be cationic electrocoated, the phosphate conversion coating is one suitable as a conversion coating for this purpose, and can be applied by an acidic aqueous phosphating 40 solution which is already known in the art for this purpose. Such solutions include, for example, a solution containing from 0.4 to 1.5 g/l of zinc ion, from 5 to 40 g/l of phosphate ion, and a conversion coating accelerator. Examples of such known phosphating solutions are given in Japanese Patent Publications (unexamined) No. 107784/1980, 145180/1980 and 131177/1980.
Particularly effective is applying the phosphate conversion coating by dipping the metal surface 45 into an acidic aqueous phosphating solution containing from 0.5 to 1.5 g/l, preferably from 0.7 to 1.2 g/l, of zinc ion, from 5 to 30 g/l, preferably from 10 to 20 g/l, of phosphate ion, and a conversion coating accelerator. The accelerator can be at least one of the following: 0.01 to 0.2 g/l, preferably 0.04 to 0.15 g/l, of nitrate ion, 0.05 to 2 g/l, preferably 0.1 to 1.5 g/l, of m-nitrobenzene suiphonate ion, and 0.5 to 5 g/l, preferably 1 to 4 g/l, of hydrogen peroxide (as 100% H202). The phosphating solution may 50 optionally also contain 1 to 10 g/l, preferably 2 to 8 g/l, of nitrate ion, and/or 0.05 to 2 g/l, preferably 0.2 to 1.5 g/l, of chlorate ion.
In this phosphating solution, when the amount of zinc ion is less than about 0.5 g/l, an even phosphate film is not formed on an iron-based surface, and a partially blue-coloured film is formed. On the other hand, when the amount is greater than about 1.5 g/l, then even though an even phosphate 55 film is formed, the film tends to be a coarse, leaf-like crystalline film, which is unsuitable as an undercoating for cationic electrocoating. When the amount of phosphate ion is below about 5 g/l, the film tends to be uneven. On the other hand, when the amount exceeds about 30 g/l, no further improvement in the phosphate coating is realized, and it is therefore uneconomical to use such increased quantities of phosphate. When the amount of the specified conversion coating accelerators is 60 below about the lower limit given, the conversion coating on an iron-based surface is inadequate, and yellow rust, etc. are formed readily on the surface. On the other hand, when the amount is above about the upper limit given, a blue-coloured uneven film forms on an iron-based surface.
Recently in the automotive industry, steel components have been employed that are plated on one surface only with zinc or an alloy of zinc. When such metal components having both iron-based and
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GB 2 097 429 A 2
zinc-based surfaces are employed, it is preferred that the phosphating solution discussed above also contain 0.6 to 3 g/l, preferably 0.8 to 2 g/l, of manganese ion, or 1 to 4, preferably 2 to 2.5 g/l, of nickel ion. It is even more preferred to include both manganese and nickel ions, and when both are included, the manganese ion is preferably employed in the range given above and the nickel ion is employed in 5 the range of 0.1 to 4 g/l, preferably 0.3 to 2 g/l.
Alternatively, a spray process can be utilized to apply the phosphate coating to the metal surface. When a spray process is employed, the following solution is preferred: an acidic aqueous phosphating solution containing from 0.4 to 1 g/l, preferably 0.5 to 0.9 g/l, of zinc ion, 5 to 40 g/l, preferably 10 to 20 g/l, of phosphate ion, 2 to 5 g/l, preferably 2.5 to 4 g/l of chlorate ion, and 0.01 to 0.2 g/l, preferably 10 0.04 to 0.15 g/l, of nitrite ion.
In the above treating solution for use in a spray process, when the amount of zinc ion is less than about 0.4 g/l, an even phosphate film is not formed on an iron-based surface, and a partially blue-coloured film is formed. On the other hand, when the amount is greater than about 1 g/l, then even though an even phosphate film is formed, it tends to be a coarse leaf-like crystalline film, which is 15 unsuitable as an undercoating for cationic electrocoating. When the amount of phosphate ion is below about 5 g/l, the film tends to be uneven. On the other hand, when the amount is greater than about 40 g/l, no further improvement in the phosphate coating is realized, and it is therefore uneconomical to use such increased amounts of phosphate. When the amount of chlorate ion is below about 2 g/l, then even though an even film is formed, the film tends to be a coarse leaf-like crystalline film, which is 20 unsuitable as an undercoating for cationic electrocoating. On the other hand, when the amount is greater than about g/l, an uneven blue-coloured film is formed on an iron-based surface. When the amount of nitrate ion is below about 0.01 g/l, the conversion coating is inadequate, and an inferior film with yellow rust, etc. is formed on an iron-based surface. On the other hand, when the amount is greater than about 0.2 g/l, it tends to form a blue-coloured uneven film on an iron-based surface. 25 As sources of the ions used in the acidic phosphating solutions discussed above, commonly known sources can be utilized, for example zinc oxide, zinc carbonate or zinc nitrate for zinc ions; phosphoric acid, sodium phosphate or zinc phosphate for phosphate ions; sodium nitrite or ammonium nitrite for nitrite ions; sodium m-nitrobenzene sulphonate form-nitrobenzene sulphonate ions; hydrogen peroxide for hydrogen peroxide; chloric acid, sodium chlorate or ammonium chlorate for chlorate ions; 30 manganese carbonate, manganese nitrate, manganese chloride or manganese phosphate for manganese ions; and nickel carbonate, nickel nitrate, nickel chloride or nickel phosphate for nickel ions.
Phosphating of the metal surfaces with the acidic aqueous solutions for phosphating discussed above can be carried out in accordance with conventional procedures. For example, the metal surfaces, which have been subjected, as needed, to degreasing and then to a known surface pretreatment 35 (generally employed prior to a dipping treatment), where the dipping treatment is used for phosphating, can be treated at 40° to 70°C, preferably at 45° to 60°C, for 15 seconds or more (preferably for 30 to 120 seconds), and thus a desired phosphate coating film of low film amount (1.5 to 3 g/m2) is produced on iron-based surfaces. Also, a uniform phosphate film is formed thereby on zinc-based surfaces. In this dipping treatment, for application to articles of complicated configuration having many pockets etc., 40 such as car bodies, it is advantageous to adopt the procedure disclosed in Japanese Patent Publication No. 107784/1980, of treating by dipping for 15 seconds or more (preferably for 30 to 90 seconds), followed by spraying for 2 seconds or more (preferably for 5 to 45 seconds). Where phosphating is carried out by a spray treatment, the phosphating solution can be sprayed onto the metal surfaces at the same temperature as is used for the dipping treatment discussed above for 40 seconds or more 45 (preferably for 1 to 3 minutes), to produce a desired phosphate coating film of low film amount (1 to 1.8 g/m2) on iron-based surfaces. Again, an even phosphate film is also formed on zinc-based surfaces.
After the formation of the phosphate coating film, the metal so treated may be washed with water according to conventional methods, followed by an after-treatment in accordance with the present invention as described below.
50 The after-treatment involves treating the phosphated metal surface with an aqueous solution having a pH of 3 to 7, preferably 4 to 6, and containing:
(a) at least 0.05 g/l, preferably at least 0.1 g/l, (as Zr02) of water-soluble fluorozirconium compound; and
(b) at least 0.05 g/l of myo-inositol phosphate and/or water-soluble salt thereof;
55 wherein the molar ratio of (a) to (b) is in the range of 1:1 to 50:1, preferably 2:1 to 40:1.
The preferred water-soluble zirconium compound is fluorozirconic acid or a salt thereof with a volatile base such as ammonia, a lower alkylamine or a hydroxy lower alkylamine (e.g. monoethanolamine, diethanolamine, triethanolamine, methylamine, ethylamine or dimethylamine). Alkali metal salts and alkaline earth metal salts of fluorozirconic acid exhibit a tendency to leave 60 corrosive substances on the surface of the metal after the above-mentioned treatment step, and they are therefore not preferred. Neither zirconium carboxylates nor zirconium hydroxcarboxylates exhibit as . beneficial an effect of the present invention as do fluorozirconic acid and its salts with volatile bases. When the amount of the water-soluble zirconium compound is less than 0.05 g/l, neither the adhesion nor the corrosion-resistance of the coating film after cationic electrocoating is improved.
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GB 2 097 429 A 3
The myo-inositol phosphates and water-soluble salts thereof used in the above-mentioned aqueous solution are esters of myo-inositol having 1 to 6 phosphate groups. Phytic acid is a commercially available product that can be employed herein. Other useful phosphates can be obtained by hydrolysis of phytic acid. As water-soluble salts of myo-inositol phosphates, salts of volatile bases 5 are preferred, such as ammonia, a lower alkylamine, or a hydroxy-lower alkylamine (examples of these bases being specified above).
When the molar ratio of (a) to (b) is less than 1:1, a zirconium salt of myo-inositol phosphate is riot formed on the phosphated metal surface, and it is this salt that improves the corrosion resistance of the metal surface. On the other hand, when the ratio exceeds 50:1, the stability of zirconium ion in the 10 solution is diminished.
As stated above, the pH of the above-mentioned solution is in the range 3 to 7. When phytic acid is employed in the practice of the invention, the pH of the solution is strongly affected by its concentration. For example, the pH of a 0.1,0.01, 0.001, and 0.0001, mole/I aqueous solution of phytic acid is respectively 0.9, 1.7, 2.68, and 3.61. When the pH of the present solution is lower than about 3, 15 the phosphate film on the metal surface dissolves excessively and the benefits of the invention cannot be fully realized. On the other hand, when the pH exceeds about 7, a zirconium salt of for example phytic acid is not formed readily on the metal surface, and the beneficial effects of the invention cannot be realized. Accordingly the pH must be adjusted, as necessary, to obtain a pH within the required range.
As pH increasing agents, volatile bases such as ammonia, a lower alkylamine or a hydroxy-lower 20 alkylamine may be employed (and examples of these bases are specified above). Accordingly, a portion of the volatile base needed for pH control can be present as a salt of fluorozirconic acid and/or as a salt of the myo-inositol phosphate. In general, at least about 4 moles of volatile base is required per mole of myo-inositol phosphate. As a pH lowering agent, phosphoric acid may be employed.
The aqueous solution used to after-treat a phosphated metal surface preferably contains 25 substantially no substance which will form a corrosive residue on the metal surface. Thus, the aqueous solution preferably contains substantially no alkali metal ions, alkaline earth metal ions, or any organic acid that will form a water-soluble chelate compound.
The treatment of the phosphated metal surface with the above-mentioned solution can be effected by any conventional contacting method such as by dipping or spraying. The treating 30 temperature is preferably in the range of from room temperature to 90°C. The treatment time is at least long enough to wet the metal surface sufficiently with the solution, and is usually in the range of from 5 seconds to 5 minutes. When contacting is by dipping, a cathodic electrolysis treatment may be utilized therefor.
When the solution used to treat the phosphated metal surface contains substantially no substance 35 which will form a corrosive residue, as is preferred, the metal surface so treated may be dried without first washing witff water. However, when the metal surface is to be dipped into an electrocoating bath for cationic electrocoating, it is desirable first to rinse the metal surface with pure water (which does not in any way diminish the beneficial effects produced by the present process).
Examples of metal surfaces that can be treated by the process of the invention include zinc-based 40- surfaces such as zinc plated steel plate by hot dipping, alloyed zinc plated steel plate by hot dipping, zinc plated steel plate by electroplating, and iron-based surfaces.
The invention is illustrated by the following Examples.
EXAMPLES
Five Examples using the process of the invention (referred to hereinafter as INVENTIVE EXAMPLE 45 1 to INVENTIVE EXAMPLE 5) were carried out together with nine Examples given for comparison purposes (referred to hereinafter as COMPARISON EXAMPLE 1 to COMPARISON EXAMPLE 9).
The treating techniques used, which are referred to in Table 1, are given in detail below. The aqueous phosphating compositions of each Example are set forth in Table 1, together with the treating solutions used thereafter on the phosphated surfaces, referred to in Table 1 as "After Treatment". The 50 metal surfaces treated and the test results obtained at different stages of coating the metal surfaces are given in Table 2.
Samples of all four metal surfaces given in Table 2 were treated simultaneously according to the following procedure:
degreasing — washing with water — surface conditioning (used only where a dipping process is 55 used for applying a conversion coating) — conversion coating — washing with water — after-treatment — washing with pure water — drying — coating.
A. Conditions for applying a conversion coating by the dipping process:
(a) degreasing, using an alkaline degreasing agent (Nippon Paint Co., 'RIDOLINE SD200", 2% by weight) which was sprayed on the metal surfaces at 60°C for 1 minute, followed by dipping in the
60 solution for 2 minutes;
(b) the metal surfaces were then washed with tap water at room temperature for 15 seconds;
(c) the metal surfaces were next dipped into a surface conditioner (Nippon Paint Co., "FIXODINE 5N—5, 0.1% by weight) at room temperature for 15 seconds;
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GB 2 097 429 A 4
(d) the metal surfaces were then dip treated with a phosphating solution given in Table 1 for dip treating at 52°Cfor 120 seconds to apply a conversion coating thereto; and
(e) the metal surfaces were washed with tap water at room temperature for 1 5 seconds.
B. Conditions for applying a conversion coating by the spray process:
5 (a) degreasing, using an alkaline degreasing agent (Nippong Paint Co., "RIDOLINE SD200", 2% by 5 weight) which was sprayed on the metal surfaces at 60°C for 2 minutes;
(b) the metal surfaces were then washed with tap water at room temperature for 15 seconds;
(c) the metal surfaces were then spray treated with a phosphating solution given in Table 1 for spray treating at 50°C for 120 seconds; and
10 (d) the metal surfaces were washed with tap water at room temperature for 15 seconds. 10
C. Conditions for After-Treatment:
(a) after step A(e) or B(d), whichever is applicable, the metal surfaces without drying, were dip or spray treated with a Treating Solution given in Table 1 at 30°C for 10 to 30 seconds;
(b) the metal surfaces were then dip treated with deionized water at room temperature for 15
15 seconds; and 15
(c) the metal surfaces were dried in hot air at 100°C for 10 minutes. The appearance and film weight of the metal surfaces were determined and the results set forth in Table 2.
(d) a cationic electrocoating material (Nippon Paint Co., "Power Top U—30 Dark Gray") was coated to 20 fi thickness onto the treated metal surfaces (voltage 180V., treatment time 3 minutes), followed
20 by baking at 180°C for 30 minutes. One sample of each electrocoated plate so obtained was subjected 20 to the brine spray test;
(e) a second sample of each electrocoated plate so obtained was coated with an intermediate coating material (Nippon Paint Co., "0RGAT0778 Gray") to fi thickness, followed by baking at 140°Cfor 20 minutes, and a top coating material (Nippon Paint Co., "ORGAT0626 Margaret White") in 40 fi
25 thickness was then applied, followed by baking as above. Accordingly, coated plates with a total of 3 25 coatings and 3 bakings were obtained. All the thus coated plates were subjected to the adhesion test, and the thus coated cold rolled steel plate also to the spot rusting test.
The testing procedures referred to above are described below:
(A) Brine spraying test (JIS—Z—2871):
30 Cross-cuts were made on an electrocoated plate; 5% brine was sprayed thereon for 500 hours 30
(zinc plated steel plate) or 1000 hours (cold rolled steel plate).
(B) Adhesion test:
After dipping a coated plate in deionized water at 50°Cfor 10 days, grids (100 squares) were made at 1 mm intervals or at 2 mm intervals using a sharp cutter; and adhesive tape was attached to 35 each surface; and the number of squares of coating film that remained on the plate after the removal of 35 the adhesion tape were counted.
(C) Spot rusting test:
A coated plate was set at a 15 degree angle to the horizontal plane, and an arrow with a cone shaped head with a 90 degree vertical angle, made of alloyed steel (material quality, JIS—G—4404, 40 hardness Hv 700 or higher), weighing 1.00 g and 14.0 mm in total length was dropped repeatedly from 40 a distance of 1 50 cm, until scratches were made on the coated surface. Subsequently, the coated plate was subjected to 4 cycles of testing, each cycle consisting of first the brine spray test (JIS—Z—2871, 24 hours), second, a moisture test (temperature of 40°C, relative humidity 85%, 120 hours), and third, standing at room temperature (24 hours). After testing, the average value (mm) of the largest diameter 45 of rust spots and blisters was obtained, with the results shown in Table 2. 45
TABLE 1
Inventive
Inventive
Comparison
Comparison
Comparison
Example 1
Example 2
Example 1
Example 2
Example 3
+-» c
Zn
(g/l)
0.8
0.6
0.3
0.6
0.6
CD C
P04
(g/l)
14.0
14.3
10.3
14.3
14.3
c +->
CO
O)
Mn
(g/D
0)
~ c
Ni
(g/l)
0.5
0.53
0.53
0.53
H
O)
ro .2
-C +-"
N02
(g/l)
0.06
0.08
0.1
0.08
0.08
c a =
CO o h2o2
(g/l)
03
o
_gco no3
(g/l)
4.0
4.2
4.2
4.2
o
Q_
CI03
(g/l)
0.7
3.0
0.16
3.0
3.0
o
*0)
Total Acidity (points)
17
16
11
16
16
CD >
Free Acidity (points)
0.9
0.6
0.3
0.6
0.6
O
o
Treatment Method dipping spray spray spray spray
Phytic Acid
(g/l)
0.64
0.64
0.64
1.00
*->
m c
(NH4)2ZrF6(asZr02)
(g/l)
0.54
0.54
0.54
0.68
i
O
CO ♦
CD
E
C pO
%-• V* CO 3
(NH.LZrFg/Phytic Acid (molar ratio)
4.53/1
4.53/1
4.53/1
3.63/1
03
£ o 1- CO
Base for adjusting pH
nh3
nh3
nh3
NaOH
i—
H
pH
5.0
5.0
5.0
3.0
4.9
i_
CD
Base/Phytic Acid (molar ratio)
7.6/1
7.6/1
7.6/1
2.6/1
<
Treatment Time (second)
20
30
30
30
30
Treatment Method
dipping spray spray spray spray
* Ammonium Zirconium Glycolate used (calculated as Zr02)
TABLE 1 (Continued)
Comparison Example 4
Comparison Example 5
Inventive Example 3
Inventive Example 4
Conversion Coating Treatment
Ui
£ = cS .9
Q. .5
TO O ° CO £L
Zn (g/l) P04 (g/l) Mn (g/l) Ni (g/l) N02 (g/l) H202 (g/l) N03 (g/l) CI03 (g/l)
0.6 14.3
0.53 0.08
4.2 3.0
1.0 14.0
0.5 0.06
4.0 0.7
1.0 14.0 0.8 0.3 0.06
4,0 0.7
1.0 14.0 0.8 0.3 0.06
4.0 0.7
Total Acidity (points) Free Acidity (points)
16 0.6
17 0.9
18 0.9
18 0.9
Treatment Method spray dipping dipping dipping
After Treatment a) c c _o "■P "+-»
(0 3
£ o h- to
Phytic Acid (g/l) (NH4)2ZrF6(as Zr02) (g/l)
0.5
/
0.64 0.54
0.32 0.27
(NH4)2ZrFg/Phytic Acid (molar ratio) Base for adjusting pH pH
Base/Phytic Acid (molar ratio)
NaOH 3.0
4.53/1
nh3
5.0 7.6/1
4.53/1
nh3
6.0 8.7/1
Treatment Time (second) Treatment Method
30 spray
10 dipping
10
dipping
TABLE 1 (Continued)
Inventive
Comparison
Comparison
Comparison
Comparison
Example 5
Example 6
Example 7
Example 8
Example 9
4-»
c
Zn
(g/D
1.0
3.0
1.0
1.0
1.0
0 p
C
PO4
(fj/D
14.0
20.0
14.0
14.0
14.0
+•» CO
+-»
Mn
(g/l)
0.8
0.8
0.8
0.8
0.8
Q)
L.
o
Ni
(g/l)
0.3
0.3
0.3
0.3
0.3
H
D)
CO
no2
(g/l)
0.06
0.06
0.06
0.06
C
c h2o2
(g/l)
1.0
CO
o
CO
no3
(g/l)
4.0
4.0
4.0
4.0
4.0
O c
Q.
CO
CI03
(g/l)
0.7
0.7
0.7
0.7
0.7
o
'55
L_
.c
Q_
Total Acidity (points)
18
26
18
18
18
> c
Free Acidity (points)
0.9
1.0
0.9
0.9
0.9
o a
Treatment Method dipping dipping dipping dipping dipping
c o
Phytic Acid
(g/l)
0.32
0.64
0.5
\
+.» c
3
(NH4)2ZrF6(as Zr02)
(g/l)
0.27
0.54
0.3
\
CD
E +-•
o w
CD
(NH4)2ZrF_/Phytic Acid (molar ratio)
4.53/1
4.53/1
\
CO CD
C
Base for adjusting pH
nh3
nh3
NaOH
\
i-
CO
pH
5.0
5.0
4.9
3.0
\
CD §
H
Base/Phytic Acid (molar ratio)
7.6/1
7.6/1
\
*3.
Treatment Time (second)
10
10
30
30
\
Treatment Method
dipping dipping spray spray
\
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GB 2 097 429 A 8
TABLE 2
Metal
Test Item
Inventive Example 1
Inventive Example 2
Comparison Example 1
Hot
Dipped
Zinc
Alloy
Plated on
Steel Plate
Film Appea Film Weigh Brine Spray (average in
Adhesivity-
'ance (g/m2)
mm) * 2 mm cuts 1 mm _ cuts
Good Evenness 4.5
2.5
100/100
100/100
Good Evenness 4.0
2.5
100/100
100/100
Good Evenness 4.3
4.5
35/100
0/100
Electro-Plated Zinc on Steel Plate
Film Appeal Film Weighl Brine Spray (average in
Adhesivity-
■ance (g/m2)
mm) ' 2 mm cuts 1 mm .cuts
Good Evenness 3.5
3.0
100/100
90/100
Good Evenness 3.2
3.5
95/100
85/100
Good Evenness 3.3
8.0
0/100
0/100
Electro-
Plated
Zinc
Alloy on
Steel Plate
Film Appeal Film Weighl Brine Spray (average in
Adhesivity-
•ance (g/m2)
rim) r 2 mm cuts 1 mm .cuts
Good Evenness 4.0
2.0
100/100
95/100
Good Evenness 3.6
2.5
100/100
90/100
Good Evenness 3.9
4.0
30/100
0/100
Cold Rolled Steel Plate
Film Appear
Film Weighl Brine Spray (average in
Adhesivity«
Spot Rustin (average in ance
•(g/m2)
mm) ' 2 mm cuts 1 mm .cuts 3
mm)
Good Evenness and Denseness 3.1
1.0>
100/100
100/100
0.86
Good Evenness and Denseness 1.4
1.0>
100/100
100/100
0.88
Good Evenness and Denseness 1.6
1.5
50/100 0/100 1.80
9
GB 2 097 429 A 9
TABLE 2 (Continued)
Metal
Test Item
Comparison Example 2
Comparison Example 3
Comparison Example 4
Hot
Dipped
Zinc
Alloy
Plated on
Steel Plate
Film Appea Film Weighl Brine Spray (average in
Adhesivity
■ance (g/m2)
mm) '2 mm cuts 1 mm cuts
Good Evenness 4.0
6.0
0/100 0/100
Good Evenness 4.0
5.5
55/100
0/100
Good Evenness 4.0
7.0
20/100
0/100
Electro-Plated Zinc on Steel Plate
Film Appear Film Weight Brine Spray (average in
Adhesivity -
ance (g/m2)
mm) ' 2 mm cuts 1 mm _ cuts
Good Evenness 3.2
6.5
0/100
0/100
Good Evenness 3.2
8.5
20/100
0/100
Good Evenness 3.2
6.0
0/100
0/100
Electro-
Plated
Zinc
Alloy on
Steel Plate
Film Appear Film Weight Brine Spray (average in
Adhesivity -
ance (g/m2)
mm) '2 mm cuts 1 mm cuts
Good Evenness 3.6
5.5
0/100
0/100
Good Evenness 3.6
5.0
60/100
0/100
Good Evenness 3.6
6.5
15/100
0/100
Cold Rolled Steel Plate
Film Appear
Film Weight Brine Spray (average in
Adhesivity -
Spot Rustinc (average in ance
(g/m2)
nm) '2 mm cuts 1 mm .cuts 3
nm)
Good Evenness and Denseness
1.4
3.5 60/100 15/100
2.45
Good Evenness and Denseness 1.4
3.0
80/100
30/100
1.21
Good Evenness and Denseness 1.4
3.0
45/100
10/100
2.66
10
GB 2 097 429 A 10
TABLE 2 (Continued)
Metal
Test Item
Comparison Example 5
Inventive Example 3
Inventive Example 4
Hot
Dipped
Zinc
Alloy
Plated on
Steel Plate
Film Appear
Film Weighl Brine Spray (average in
Adhesivity -
ance
(g/m2)
mm) *2 mm cuts 1 mm cuts
Good Evenness 4.5 3.5 58/100 0/100
Good Evenness and Denseness 3.0
1.0
100/100
100/100
Good Evenness and Denseness 3.0
1.5
100/100
100/100
Electro-Plated Zinc on Steel Plate
Film Appear
Film Weighl Brine Spray (average in
Adhesivity ance
(g/m2)
mm) '2 mm cuts 1 mm cuts
Good Evenness 3.5 6.5 24/100 0/100
Good Evenness and Denseness 2.2
1.5
100/100
100/100
Good Evenness and Denseness 2.2
1.5
100/100 100/100
Electro-
Plated
Zinc
Alloy on
Steel Plate
Film Appear
Film Weight Brine Spray (average in
Adhesivity -
ance
(g/m2)
mm) *2 mm cuts 1 mm cuts
Good Evenness 4.0 3.0 64/100 8/100
Good Evenness and Denseness 3.1
1.0
100/100
100/100
Good Evenness and Denseness 3.1
1.5
100/100 100/100
Cold Rolled Steel Plate
Film Appear
Film Weight Brine Spray (average in
Adhesivity -
Spot Rustinc (average in ance
(g/m2)
mm) ' 2 mm cuts 1 mm ^cuts 3
nm)
Good Evenness and Denseness 3.1
1.5
100/100
100/100
1.10
Good Evenness and Denseness 2.3
1.0>
100/100
100/100
0.70
Good Evenness and Denseness 2.3
1.0>
100/100
100/100
0.76
11
GB 2 097 429 A 11
TABLE 2 (Continued)
Metal
Test Item
Inventive Example 5
Comparison Example 6
Hot
Dipped
Zinc
Alloy
Plated on
Steel Plate
Film Appea
Film Weigh Brine Spray (average in
Adhesivity ranee
(g/m2)
mm) '2 mm cuts 1 mm cuts
Good Evenness and Denseness 3.0
1.5
100/100
100/100
Good Evenness 4.6 3.5 30/100 0/100
Electro-Plated Zinc on Steel Plate
Film Appeal
Film Weighl Brine Spray (average in
Adhesivity -
ance
(g/m2)
mm) * 2 mm cuts 1 mm _ cuts
Good Evenness and Denseness 2.2
1.5
100/100
100/100
Good Evenness 3.8 6.0 0/100 0/100
Electro-
Plated
Zinc
Alloy on
Steel Plate
Film Appear
Film Weight Brine Spray (average in
Adhesivity «
ance
(g/m2)
nm) ' 2 mm cuts 1 mm cuts
Good Evenness and Denseness 3.1
1.0
100/100
100/100
Good Evenness 4.5 3.0 45/100 0/100
Cold Rolled Steel Plate
Film Appear
Film Weight Brine Spray (average in
Adhesivity •
Spot Rustini (average in ance
(g/m2)
nm) "2 mm cuts 1 mm cuts rim)
Good Evenness and Denseness 2.3
1.0>
100/100
100/100
0.72
Good Evenness
3.4
2.5 60/100
0/100 1.96
12
GB 2 097 429 A 12
TABLE 2 (Continued)
Metal
Test Item
Comparison Example 7
Comparison Example 8
Comparison Example 9
Hot
Dipped
Zinc
Alloy
Plated on
Steel Plate
Film Appeal
Film Weighl Brine Spray (average in
Adhesivity ance
(g/m2)
mm) "2 mm cuts 1 mm cuts
Good Evenness and Denseness 3.0
1.5
100/100 100/100
Good Evenness and Denseness 3.0
2.0
100/100
95/100
Good Evenness and Denseness 3.0
1.5
100/100
100/100
Electro-Plated Zinc on Steel Plate
Film Appear
Film Weighl Brine Spray (average in
Adhesivity-
ance
(g/m2)
mm) *2 mm cuts 1 mm cuts
Good Evenness and Denseness 2.2
2.5
100/100
93/100
Good Evenness and Denseness 2.2
3.5
95/100
90/100
Good Evenness and Denseness 2.2
2.5
100/100
95/1000
Electro-
Plated
Zinc
Alloy on
Steel Plate
Film Appear
Film Weighl Brine Spray (average in
Adhesivity ■
ance
(g/m2)
mm) '2 mm cuts 1 mm cuts
Good Evenness and Denseness 3.1
1.5
100/100
100/100
Good Evenness and Denseness 3.1
2.5
100/100
97/100
Good Evenness and Denseness 3.1
2.0
100/100
100/100
Cold Rolled Steel Plate
Film Appear
Film Weighl Brine Spray (average in
Adhesivity -
Spot Rustin (average in ance
(g/m2)
nm) *2 mm cuts 1 mm cuts
3
nm)
Good Evenness and Denseness 2.3
1
100/100 100/100 0.94
Good Evenness and Denseness 2.3
1.5
100/100
100/100
0.98
Good Evenness and Denseness 2.3
1
100/100 100/100 0.98
13
GB 2 097 429 A 13

Claims (16)

1. A process for treating a metal surface having a phosphate conversion coating characterised by treating said coated surface with an aqueous solution containing:
(a) at least 0.05 g/l (as Zr02) of water-soluble fluorozirconium compound; and 5 (b) at least 0.05 g/l of myo-inositol phosphate and/or water-soluble salt thereof; 5
the aqueous solution having a pH in the range 3 to 7, and the molar ratio of (a) to (b) being in the range 1:1 to 50:1.
2. A process according to claim 1 characterised by employing as (a) at least 0.1 g/l (as Zr02) of water-soluble fluorozirconium compound.
10
3. A process according to claim 1 or 2 characterised in that the myo-inositol phosphate or water- 10 soluble salt thereof is one or both of phytic acid and a salt thereof with a volatile base.
4. A process according to any one of the preceding claims characterised in that the molar ratio of (a) to (b) is from 2:1 to 40:1.
5. A process according to any one of the preceding claims characterised in that the water-soluble
15 fluorozirconium compound is one or both of fluorozirconic acid and a salt thereof with a volatile base. 15
6. A process according to claim 5 characerised in that the salt with a volatile base is the ammonium salt.
7. A process according to any one of the preceding claims characterised in that the pH of the aqueous solution is adjusted into said range by the addition of a volatile base thereto.
20
8. A process according to any one of the preceding claims characterised in that the metal surface 20 is iron-based or zinc-based.
9. A process according to claim 8 characterised by treating an article which has an iron-based surface and a zinc-based surface.
10. A process according to any one of the preceding claims characterised in that the phosphate
25 conversion coating is applied by dipping the metal surface into an acidic aqueous phosphating solution 25 containing from 0.5 to 1.5 g/l of zinc ion, from 5 to 30 g/l of phosphate ion, and a conversion accelerator.
11. A process according to claim 10 characterised in that the conversion coating accelerator is at least one selected from the group consisting of 0.01 to 0.2 g/l of nitrite ion, 0.05 to 2 g/l of m-
30 nitrobenzene sulphonate ion, and 0.5 to 5 g/l of hydrogen peroxide. 30
12. A process according to claim 10 or 11 characterised in that the phosphating solution also contains
(i) 1 to 10 g/l of nitrate ion; and/or
(ii) 0.05 to 2 g/l of chlorate ion.
35
13. A process according to any one of claims 1 —9 characterised in that the phosphate conversion 35
coating is applied by spraying the metal surface with an acidic aqueous phosphating solution containing 0.4 to 1 g/l of zinc ion, 5 to 40 g/l of phosphate ion, 2 to 5 g/l of chlorate ion, and 0.01 to 0.02 g/l of nitrite ion.
14. A process according to any one of claims 10, 11 and 13 characterised in that the phosphating
40 solution also contains 0.1 to 4 g/l of nickel ion. 40
15. A process according to any one of the preceding claims characterised in that the metal surfaces is subsequently cationic electrocoated.
16. A composition for treating a metal surface having a phosphate conversion coating,
characterised in that the composition is an aqueous solution defined in any one of claims 1—7.
Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1982. Published by the Patent Office, 25 Southampton Buildings, London, WC2A 1AY, from which copies may be obtained
GB8208993A 1981-03-26 1982-03-26 Process and composition for treating phosphated metal surfaces Withdrawn GB2097429A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56044820A JPS6017827B2 (en) 1981-03-26 1981-03-26 Pretreatment method for metal surfaces for cationic electrodeposition coating

Publications (1)

Publication Number Publication Date
GB2097429A true GB2097429A (en) 1982-11-03

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB8208993A Withdrawn GB2097429A (en) 1981-03-26 1982-03-26 Process and composition for treating phosphated metal surfaces

Country Status (6)

Country Link
EP (1) EP0061911A1 (en)
JP (1) JPS6017827B2 (en)
FR (1) FR2502645A1 (en)
GB (1) GB2097429A (en)
IT (1) IT1151530B (en)
NL (1) NL8201265A (en)

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* Cited by examiner, † Cited by third party
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Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6312812B1 (en) 1998-12-01 2001-11-06 Ppg Industries Ohio, Inc. Coated metal substrates and methods for preparing and inhibiting corrosion of the same
US6168868B1 (en) 1999-05-11 2001-01-02 Ppg Industries Ohio, Inc. Process for applying a lead-free coating to untreated metal substrates via electrodeposition
US6217674B1 (en) 1999-05-11 2001-04-17 Ppg Industries Ohio, Inc. Compositions and process for treating metal substrates
JP2008184690A (en) * 2002-12-24 2008-08-14 Nippon Paint Co Ltd Pretreatment method for coating
CA2644799C (en) 2006-03-01 2014-05-27 Nippon Paint Co., Ltd. Composition for metal surface treatment, metal surface treatment method, and metal material
EP1997934B1 (en) 2006-03-01 2014-07-30 Chemetall GmbH Composition for metal surface treatment, metal surface treatment method, and metal material
JP6515389B2 (en) * 2015-10-09 2019-05-22 日本製鉄株式会社 Sliding member and method of manufacturing the same
US10113070B2 (en) * 2015-11-04 2018-10-30 Ppg Industries Ohio, Inc. Pretreatment compositions and methods of treating a substrate
CN111593380A (en) * 2020-06-30 2020-08-28 武汉钢铁有限公司 Acidic electro-galvanized iron alloy plating solution additive for high-iron-content plating layer and application method thereof

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3076434A (en) * 1960-04-04 1963-02-05 Niemoller Gerhard Animal actuated watering pump
US3076734A (en) * 1960-07-01 1963-02-05 Acme Steel Co Protective coatings on metals
US3695942A (en) * 1970-12-02 1972-10-03 Amchem Prod Zirconium rinse for phosphate coated metal surfaces
JPS535622B2 (en) * 1973-02-12 1978-03-01
US3895970A (en) * 1973-06-11 1975-07-22 Pennwalt Corp Sealing rinse for phosphate coatings of metal
US3912548A (en) * 1973-07-13 1975-10-14 Amchem Prod Method for treating metal surfaces with compositions comprising zirconium and a polymer
JPS5292836A (en) * 1976-01-30 1977-08-04 Nippon Packaging Kk Zinc or its alloys subjected to chemical conversion
US4148670A (en) * 1976-04-05 1979-04-10 Amchem Products, Inc. Coating solution for metal surface
US4110129A (en) * 1977-02-03 1978-08-29 Oxy Metal Industries Corporation Post treatment of conversion-coated zinc surfaces
US4187127A (en) * 1978-12-07 1980-02-05 Nihon Parkerizing Co., Ltd. Surface processing solution and surface treatment of aluminum or aluminum alloy substrate

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107604347A (en) * 2017-09-29 2018-01-19 马鞍山松鹤信息科技有限公司 A kind of architectural shape surface conditioning agent and its preparation technology

Also Published As

Publication number Publication date
NL8201265A (en) 1982-10-18
IT8220440A0 (en) 1982-03-26
JPS6017827B2 (en) 1985-05-07
IT1151530B (en) 1986-12-24
EP0061911A1 (en) 1982-10-06
JPS57158397A (en) 1982-09-30
FR2502645A1 (en) 1982-10-01

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