JPS58151491A - Production of colored zinc electroplated metallic plate - Google Patents

Abstract

PURPOSE:To obtain a zinc electroplated steel plate having dense and beautiful colored layers of dark color without application of heat treatment, by subjecting a metallic plate to composite zinc electroplating then to an anodic electrolyzing treatment in a bath contg. water soluble metallic compds. CONSTITUTION:A metallic plate is subjected to zinc electroplating in an acidic zinc electroplating bath consisting essentially of Zn added with >=1 kind among water-soluble compds. of Co, Ni, Mo, at 3-50g/l Co, Ni and 0.01-3g/l Mo in terms of metal. In succession, the plated metallic plate is subjected to an anodic electrolyzing treatment of 5-500 coulomb/dm quantity of electricity in a bath contg. 1-100g/l >=1 kind among water-soluble compds. of Zn, Co, Ni, Fe, Cr, Sn, Ti, V, Mn, Mg, Cu, Al, Na, K and ammonium compds. Further, silicon is coated thereon so as to be coated at 10-400mg/m<2> according to need. The zinc electroplated metallic plate having dense colored layers is obtained with easy control of color tones by the above-mentioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a colored electrogalvanized metal sheet, and more specifically, the present invention relates to a method for manufacturing a colored electrogalvanized metal sheet, and more specifically, a method for producing a colored electrogalvanized metal sheet.
<7) After composite electrogalvanizing in a bath containing one or more types, electrolytic treatment (input treatment) in a bath containing various metal compounds, etc.
This invention relates to a method for obtaining a colored electrogalvanized gold plate whose surface is colored blue-black to black.

Hitherto, various attempts have been made to write dark colors on other ship surfaces from the viewpoint of improving decorativeness, light absorption, heat absorption, and light reflection and prevention properties. These coloring methods include, for example, (1) the method of applying black paint, (the dichlorate dipping method, (to) the molybdate dipping method, (the chromic acid anhydride dipping method, (to) the sulfide dipping method, 6) Copper sulfate immersion method and others.

However, method (1) above is expensive; cheaper methods do not provide good adhesion to the eyelid membrane, and methods (2) to (2) require troublesome management of the treatment bath, resulting in an interstitial layer on the waste liquid treatment. At the same time, it was difficult to obtain a stable dark-colored film in a short period of time.

Therefore, the applicant basically proposed that the zinc plating itself be alloyed with cobalt and/or nickel. The surface of the plating layer can be colored very easily by heating the electroplated product, and organic additives may be added to the plating solution to improve corrosion resistance and appearance characteristics. An invention was proposed in which a desired colored electrolytic galvanized product could be manufactured by subjecting the surface after plating to a silicic acid post-treatment or by applying a synthetic resin paint (Japanese Patent Laid-Open No. 55-91993).

However, the heating method still has problems from an energy-saving perspective, and it is difficult to control the degree of coloring, so uniform coloring cannot always be obtained, and productivity and corrosion resistance after treatment are slightly inferior, resulting in the occurrence of a melting point. The results of the implementation have become clear.

Therefore, the present inventor was forced to create a better coloring method, and as a result of various experiments and considerations, mainly water-bathable Zn, Co, Ni, Fe, Cr, and S were used after plating.
n, Ti.

■、Kite My、C horse Aj! The plated metal plate is subjected to anodic electrolysis treatment (A treatment) in a bath containing at least one of Na or K compounds and/or ammonium group compounds.
It has been found that the above problems can be solved by doing so.

However, as proposed above, it is known that the surface of an alloy galvanized layer containing Co and Ni is colored darkly by heating, that is, by oxidation, and this oxidation phenomenon can be prevented by anodic electrolysis treatment (
This is because it was thought that it could be induced in a bath by treatment A).

That is, water-soluble Zn, Co, Ni, Fe, Cr,
Sn, Ts, V.

Mu, MW, Cu, AIL, Na or Ko>
At least one of the compounds and/or ammonium group compounds
When electrolytically treated (A treatment) in a bath containing more than 10% of the species, nascent oxygen is generated on the anode surface, and the plating layer is lightly redissolved and oxidized at the same time, resulting in an oxidation phenomenon similar to that of air heating. It is thought that the preferential oxidation of Co, Ni, or MO occurs to cause the coloring, and a dense colored layer is obtained without the generation of MO oxide particles that occurs when heating. As a result of experiments, it became clear that

An object of the present invention is to provide a method for producing a colored electrogalvanized metal sheet that allows a dense and beautiful colored layer to be obtained without heat treatment.

Another object of the present invention is to provide a method for manufacturing a board in which the processing time is extremely short.

According to the present invention, one or more types of water-soluble Co, Ni or MO compounds are used as metals, and for Co and Ni, 3 to 50 f/j! ,M
Regarding o, after electrogalvanizing a metal plate in an acidic electrogalvanizing bath mainly containing Zn added with α01 to 3φ, using the plated metal plate as an anode, water-soluble (7) Zn
, Co, Ni, Fe, Cr, Sn, Tj,
At least one of V, Mn, My, Cu, A4 Na or K compound and/or ammonium group compound
in a bath containing 1 to 100 y/i of
A method for producing a colored electrogalvanized metal sheet characterized by subjecting it to an electrolytic treatment (A treatment) of 00 coulombs/dwl, and one or more water-soluble Co, Ni or MO compounds as the metal, and 3 for Co and Ni. ~50 fA% Mo: After electrogalvanizing a metal plate in an acidic electrogalvanizing bath mainly containing Mo added with α01~3 f/it, using the plated metal plate as one electrode, water-soluble (7) Zn,
Co, Ni, Fe, Cr, Sn, Ti,
V, Mn, My.

At least one kind of Cu, kQ, Na or K compound and/or ammonium group compound in 1 to 100
Electricity 115-500 coulombs/dm in a bath containing f/12
' electrolytic treatment (A treatment), and then cathodic electrolysis treatment (B treatment) with an electric power of 5 to 500 coulombs/dd in a bath containing 5 to 200 t/It of dichromic acid and/or dichromate. A method for manufacturing a colored electrogalvanized metal sheet is provided.

The present invention will be explained in detail below.

When a metal plate is electroplated in a zinc-based bath containing water-soluble cobalt and/or nickel and/or molybdenum compounds, the plating layer naturally contains cobalt and/or molybdenum in addition to zinc. Nickel and/or MO are eutectoid. Therefore, using this electrogalvanized metal plate as an anode, water-soluble Zn, Co,
Ni, Fe, Cr, 8n, Ti, V,
Mn.

When electrolytically treated (A treatment) in a bath containing at least one compound of Na or K and/or an ammonium group compound, the Co, T, and Co present on the zinc surface are
Either Ni or Mo is preferentially oxidized and the surface becomes blue-black or black.

This phenomenon cannot be produced by the conventional anodic electrolytic treatment of a galvanized metal plate, and the presence of a small amount of the eutectoid metal, which is to serve as a color former, is indispensable.

The present invention is basically a further improvement of the invention described in the specifications of JP-A-55-91993 and JP-A-56-293. However, the present invention uses water-bathable Zn to coat a metal plate after eutectoid galvanization.

Co, Ni, Fe, Cr, an, Ti, V
, Mn, My, Cu, Ajk, Na or K
Q] Based on the new finding that a plated metal plate can be colored dark in a very short time by anodic electrolytic treatment (A treatment) in a bath containing at least one compound and/or ammonium-based compound, This was the first time that we were able to achieve the desired effect.

Here, the base metal plate includes hot-rolled steel sheets from which scale has been removed, galvanized copper sheets, furiki sheets, Ni-plated steel sheets, α-plated steel sheets, stainless steel sheets, etc., as well as Cu or C steel sheets.
Concerning genus element compounds such as u alloy plate, AIL or A1 alloy plate, the following water-soluble compounds are included: Co,
Compounds of Ni include sulfates, chlorides, acetates, nitrates, etc., and MOQ) compounds include ammonium salts, sodium salts, potassium salts, molybdenum chloride, etc. of molybdic acid.

In addition, the amount of Co and Ni compounds added is 3 to 5 as metals.
A range of 0φ is desirable, because if it is less than 3224, it will be difficult to develop color even with anodic electrolytic treatment (A treatment).
Moreover, if the number is more than 50 t, 42, it becomes difficult to perform plating and the plating properties are also deteriorated. A particularly desirable component of the cobalt and/or nickel compound is from 5 to 20 f/11 as a metal based on experience.

Further, it is desirable that the Mo compound has an αo1 to 3φ range as a metal. The reason is that if α01 f/It or less, the shield color effect is small, and if it is 31711 or more, the adhesion of the plating layer decreases.

Furthermore, one method for changing the appearance after coloring is to change the plating layer itself. In other words, by adding organic additives to the plating bath, it is possible to promote blue-black or blackening through anodic electrolytic treatment (A treatment) without using post-treatment or painting, and to produce beautiful colored galvanized metal sheets. It is possible to obtain it. Of course, it goes without saying that if you apply post-treatment or painting in addition to this, the aesthetic appearance will further increase. Suitable organic additives include water-soluble or water-dispersible polyacrylate copolymers, dianediamide/hollemaldehyde, polyvinyl alcohol, and cationic polyamines. The presence of H
A total of at least 1I11 or more of additives α1~IQ
If t/It is added, a beautiful glossy surface of deep blue-black to black color can be obtained. If the amount added is less than α1tA, there will be no effect, and if it exceeds 10 fA, the attaching property will deteriorate, so the above range is inappropriate.

In addition, the following compounds are included in the anodic electrolytic treatment (A treatment) bath performed after eutectoid curved lead plating.

That is, Zn, Co, Ni, Fe, Cr,
an, Ti, V, My, Mn, Cu.

Water-soluble compounds among sulfates, chlorides, nitrates, and acetates of AL N& or K and/or ammonium sulfate, ammonium sulfate, ammonium acetate, etc. are included.

The amount added is preferably in the range of 1 to 100 t7Qt. The fourth reason is that below 1 fA, the conductivity becomes extremely poor, and above 100 f/It becomes uneconomical.

Further, 1. The amount of electricity processed in the anodic electrolytic treatment (A treatment) in the above bath is preferably 5 to 500 corons/dwt.

If the amount of electricity is less than 5 coulombs, 4 -, the coloring effect will be small, and if it exceeds 500 coulombs/dI11", problems will arise in the adhesion of the treated film, and zn will be proportional to the amount of electricity in anodizing (A treatment). It is not economical because it has to be redissolved.

These become blue-black or black. The bare corrosion resistance of eutectoid electrogalvanized metal sheets is generally good in a mildly corrosive atmosphere (constant temperature and humidity test), but is somewhat unsatisfactory in a salt spray test. For example, in the case of a basis weight of 101, there was no change at all even after 50 days in the constant temperature and high humidity test, which was good, but white rust occurred in 30 hours in the salt spray test.

In addition, as a means to further increase the depth of the blue-black to black surface and to improve corrosion resistance, a method of applying silicic acid treatment to the surface after plating and anodic electrolytic treatment (Process A 1!!i) There is a method of applying a transparent or translucent synthetic resin coating.

The silicic acid treatment refers to the blue-black coloring of silicic acid, silicates such as lithium silicate, potassium silicate, sodium silicate, or an aqueous solution of a mixture thereof (chromic acid, chromate, or a mixture thereof is further added as necessary). It is applied to the blackened eutectoid electrogalvanized surface by, for example, dipping, spray coating, roll coating, or other means, and then dried. In this case, the amount of coating (coated film amount) is 10 to 400 mg after drying, measured as silicon.
It is important to apply the coating so that the ratio is /wl.

That is, if the amount of silicon added is less than 10 IQ/ml', there is no effect, and if it exceeds 400 m9/-, a problem will occur in the density of the treated film. In addition to the above, silicic acid treatment includes
For application of aqueous solutions containing phosphoric acid or phosphates, or water-soluble or water-dispersible organic polymers in addition to silicic acid or silicates, as described in Japanese Patent Publication Nos. 44-19686 to 45-5130. You can get it no matter what.

Further, the transparent to translucent coating film applied after the anodic electrolysis treatment (A treatment) can be obtained by diluting various natural or synthetic resins with water or organic solvents, coating, and drying.

Examples of these resin paints include boiled oil, oil varnish, volatile dry varnish, Schertz varnish, lacquer, phenolic resin varnish, phthalic acid resin varnish, urea resin varnish, melamine resin varnish, WP acid vinyl acrylic resin varnish, and styrene resin varnish. Alkyd, resin varnish, etc. Application methods include dipping, spray coating, roll coating, and others.

When the above-mentioned silicic acid treatment or resin coating is applied, the finished galvanized surface becomes deep blue-black or black, improving the aesthetic appearance and improving corrosion resistance as shown in the examples below.

In addition, cathodic electrolytic treatment (A treatment) is performed after anodic electrolytic treatment (A treatment).
B treatment) The compounds contained in the bath are dichromic acid and its
Contains sodium, potassium, ammonium, and salt.

The concentration of these baths is preferably in the range of 5 to 200 f/1. Below 5 f/IL, there is a problem with the conductivity of the bath;
G 01711 or higher is not economical. In addition, the amount of electricity for cathode electrolytic treatment (B treatment) is 5 to 500 coron/dwt.
is desirable. If it is less than 5 coulombs/ad, the effect of improving corrosion resistance is small, and if it is more than 500 coulombs/d, it is not economical.

In addition to these methods, there is also a method of further applying the above-mentioned silicic acid treatment or a transparent or translucent synthetic resin coating after cathodic electrolytic treatment (B treatment) in a dichromic acid and/or dichromate solution. These processing conditions are preferably within the ranges already described.

As described above, by carrying out the present invention, a dark colored galvanized metal plate without color unevenness can be obtained with a relatively simple process. In other words, all of the above objectives can be achieved. Therefore, the industrial value of the present invention is enormous. It goes without saying that the base metal plate may be various processed metal plates or metal parts.

Examples are shown below.

Example 1 A mild steel plate having a thickness of α4t was electrolytically degreased in a 7% caustic soda aqueous solution and then washed with water, then pickled with 70 fA sulfuric acid and washed with water to obtain a plating original plate. The original plate obtained by the above treatment was plated under the following conditions.

, plating bath composition Zn80*°7H! 0 250f/
jl state 4) Snow・80415f/I C0804・'IHxO (as Co>
8 f/It dicyandiamide formaldehyde
1t7tt Metsuki bath temperature 38
°C Current density 25 A/dWt plating amount
At 10 f/d, the obtained galvanized steel sheet containing Co was used as an anode and electrolytically treated (A treatment) under the following conditions.

Bath composition Co80 m 7HmO10t/11 (NHa) Proverb 804 10f/ffi Bath temperature
40'C Amount of electricity processed 50 coulombs/dd On the following page, 7 g of concentrated lithium silicate solution (L
After being immersed in i-snow 0:8i0m-1:4) for 3 seconds and dried, the amount of silicon added was 200q/wl.
After roll coating, it was dried with a hot dryer.

The obtained sample exhibited a beautiful deep blue-black to black color, and the film did not peel off even in a cellophane tape peeling test. or,
In the salt water fountain back test according to JIS Z2371, continuous 4
Even after 8 hours, the white appearance remained within 5%.

Example 2 In the same manner as in Example 1, a plated original plate for degreasing and pickling was plated under the following conditions.

Plating bath composition Zn8CL ・7H*0 250f/1
(NH4)zsO415F/β Nl504・7HzO (as Ni)
817n polyvinyl alcohol
2f/1 plating bath temperature: 50°C Current density: 25 A/d♂ Plating amount: 15r/Wt The obtained galvanized steel sheet containing Ni was further subjected to anodic electrolytic treatment (A treatment) under the following conditions. .

Bath composition T i804 10 f/1
Mg80a ・6H! 0 50
t/IA bath temperature 50'C Processing electricity 1 100 coulombs/d Bi Thereafter, lithium silicate was further applied in the same manner as in Example 1.

The obtained sample exhibited a beautiful dark blue-black color, and there was no peeling of the film in the cellophane tape peeling test, and it was JI8Z2371.
In a salt spray test conducted by the company, the occurrence of white rust was within 5% even after 48 hours of continuous use.

Example 3 A plating original plate that had been degreased and pickled in the same manner as in Example 1 was plated under the following conditions.

Plating bath composition Zn80n 7Hs0 250f/
j1 (NH4) Mushroom Boa 15
9/IC080i7HxO (Co and C”)
By/11 Plating bath temperature 45℃ Current density 25 klrid plating amount
15 f/wI The galvanized steel sheet containing the folded e was further subjected to anodic electrolysis treatment (A treatment) under the following conditions.

Bath composition (NH4) zoo 4 ・Fe5On ・6HzO3
01/J Bath temperature: 40℃ Processing amount of electricity: 100 coulombs/d♂After this,
Dark If 500 f/1. potassium silicate solution (
K: 8i0x -1:4) After being immersed for 3 seconds and dried, the weight as silicon was 20011g.
, 'V' after roll coating and drying with a hot dryer.

The obtained sample had a beautiful blue-black to black color, and there was no peeling of the film even in the cellophane tape peeling test, and it was JI8Z23.
In the salt spray test according to No. 71, the occurrence of white rust was within 5% even after 48 hours of continuous use.

Example 4 A plating base plate that was degreased and pickled in the same manner as in Example 1 was coated with Zn80.
a ・7Hwo 250 f/1
1 (NH4) Tomi 804 20 t/
ItCocoa・7H鵞0 (as CO)
81/It(NH*)sMoyo*m-4
H*0 0.1f/j! Current density
25νdm' Coating amount 15fβ The obtained galvanized steel sheet containing Co and Mo was further subjected to anodic electrolysis treatment (A treatment #i) under the following conditions.

Bath composition (NH4) 1804 30 f/
j! Bath temperature: 40℃ Processing amount of electricity: 100 coulombs/dm After this,
It was immersed for 3 seconds in a lithium silicate solution containing 5 tA of Crow and having a concentration of 500 y/1, and after drying, it was roll coated so that the amount of silicon deposited was 200 q/ml, and then dried with a hot dryer.

The obtained sample exhibited a beautiful deep blue-black to black color, and no peeling of the film occurred in the cellophane tape peeling test. Mata JI
There was no change at all after 48 hours of continuous salt spray test using 8Z2371.

Example 5 A plating plate No. 1 which had been degreased and pickled in the same manner as in Example 1 was plated under the following conditions.

Plating bath composition Zn80i 4Hz0 250f/j
! NiSO4・7HxO (as Ni)
Bt7th (NH4) z 804
15 f/11 plating bath temperature 40°C current density 25 A/dm plating amount 20 f/Wt The obtained galvanized steel sheet containing Ni was further subjected to anodic electrolysis treatment (A treatment) under the following conditions.

Bath composition Ni804 ・7H! 0
101/I.

AJh (804)m ・16-18H Mayuzumi 0
50F/Tomoe bath temperature 40C Processing electricity 1 400 coulombs/dIII' Then, a transparent synthetic resin paint (trade name: Campe Clear Lacquer) was spray applied. The obtained sample exhibited a beautiful blue-black to black color, and no peeling of the film occurred in the cellophane tape peeling test. Also, in the JI8z2371 salt water spray test, there was no change at all after 48 hours of continuous testing.

Example 6 A plating original plate that had been degreased and pickled in the same manner as in Example 1 was plated under the following conditions.

Plating bath composition z11804°7H*0 2501F
/41(NH4)1804 15
F/Co80n・FHsO (as Co”)
591INi80m・7H earthquake 0 (N
i) 5t/11 dicyandiamide formaldehyde 1f/It
Plating bath temperature: 38° C. Current density: 25 A/d Coating amount: 20 f/wt The obtained galvanized steel sheet containing Co and Ni was further subjected to anodic electrolysis treatment (A treatment) under the following conditions.

Bath composition A11 (804) l ・16-18Hs0 3
0r/jNam804
30r/j! Bath temperature: 45℃ Processing amount of electricity: 200 coulombs/d111′ Furthermore,
Warm 4 in a bath containing 3 of sodium dichromate/IL
Cathode treatment (B treatment) with electricity 100 coulombs/d at 0°C
Then, a transparent synthetic resin wall material was applied in the same manner as in Example 5.

The obtained sample exhibited a beautiful deep blue-black to black color, and the film did not peel off in the cellophane tape peeling test (JI8Z).
In the salt spray test using 2371, there was no change at all even after 48 hours of continuous use.

Comparative Example 1 A plating original plate that had been degreased and pickled in the same manner as in Example 1 was plated under the following conditions.

Plating bath composition Z″804°7HiO250f/ji (NH4)寞804 15 t/1
1CO8O4・7HzO' (as Co＞
8f/It plating bath temperature 38℃ Current density 25 A/d Gold plating amount
I Q t/l The obtained galvanized steel sheet containing Co had a gray color, and although there was no peeling of the film in the cellophane tape peeling test, white red rust had occurred on the entire surface after 24 hours in the salt spray test according to JI8Z2371. Comparative Example 2 A plating original plate that had been degreased and pickled in the same manner as in Example 1 was plated under the following conditions.

Plating solution composition Zn80i 7H*0 250f/l1
(NHa) Snow 80a 15
y/lCo3O4・7Hso (as Co)
8 f/It(NH4)sMoyos
4.4H*Oal f/11 dicyandiamide formaldehyde 1f/1 plating bath temperature
45℃ Current density 25 A/dwt plating amount
10 f/wl The obtained galvanized copper plate containing Co and Mo exhibited a glossy pale yellow color, and there was no peeling of the film in the cellophane tape peeling test, but JI8Z
In the salt water spray test using No. 2371, white-red rust had occurred on the entire surface after 24 hours.

Comparative Example 3 A plated base plate for degreasing and pickling was plated under the following conditions in the same manner as in Example 1.

Plating bath composition Zn80i-7H*O250t/f (NH4) z 80 a 15
t/1 plating bath temperature 40℃ Current rating 25 A/dwt plating amount
20 f/Ml The obtained galvanized steel sheet was further subjected to anodic electrolysis treatment (A treatment) under the following conditions.

Bath composition (NH4) 2804' 50
f/jt Bath temperature 40°C Processing electricity * 200 Ri-o7/di The obtained sample exhibited a gray color, and there was no peeling of the film in the cellophane tape peeling test, but in the salt water spray test according to JI8Z2371, there was no peeling after 24 hours. There was white-red rust all over.

Examples are summarized in Table 1 below.

Patent applicant: Toyo Dohan Co., Ltd.

Claims (1)

[Claims] (1) One or more water-soluble Co, Ni or Mo compounds are combined with a metal at a concentration of 3-50 f/l, M. αO1 ~3 After electrogalvanizing a metal plate in an acidic electrogalvanizing bath mainly containing zIB added with f/11, the electroplated metal plate was used as an anode and water-soluble Zl was applied.
l, C@, Ni, Fe, Cr, Sn, Ti
, V, Mn, Mg, Cu, AI, Na or K compounds and/or ammonium group compounds in a bath containing at least one type of t-1 to t0OtA.
~500 coulombs/dwt anodic electrolysis treatment (A treatment)!
A method for producing a colored electrogalvanized metal sheet, characterized in that: (b) The acidic electrogalvanizing bath further contains at least 1 of each organic compound of water-soluble or water-dispersible polyacrylate copolymer, ginandiamide formaldehyde, polyvinyl alcohol, or cationic polyamine in a total amount of 0.1 A method for producing a plated metal plate according to claim 1, wherein the bath contains a concentration of 10 to 10 f/41. (Mark) After the anodic electrolytic treatment (A treatment), an aqueous solution containing silicic acid and/or silicate and/or chromic acid and/or chromate is further applied to the plated metal plate so that the amount of silicon deposited after drying is 10.
The method for manufacturing a plated metal plate according to any one of claims 1 to 2, wherein the coating is applied so that the coating thickness is 400W. (4) The plated metal plate after the anodic electrolytic treatment (A treatment) is washed with water and dried, and then a resin paint is applied to form a transparent or translucent coating film. A method for producing a plated metal plate according to any one of the following. 6) The method for producing a plated metal plate according to any one of claims 1 to s4, wherein the metal plate is a steel plate or a non-ferrous metal plate. After a metal plate is plated with high-temperature lead in an acidic zinc plating bath, the plated metal plate is used as an anode and a water-soluble zinc plating bath is applied.
% Co, Ni, Fe, Cr, 8n, Ti,
At least one of V, Mn, Mf, Cu, A4Na or K compound and/or ammonium group compound
Electricity 5-5 in a bath containing 1-100 t/11 of seeds or more
00 coulomb/dd anodic electrolysis treatment (A treatment),
Then add dichromic acid and/or dichromate to 5 to 200
Electricity 5 to 500 coulombs/dW in a bath containing t/It
cathode of t. A method for producing a colored electrolytic galvanized metal sheet, characterized by subjecting it to electrolytic treatment (B treatment II). (2) The acidic electrogalvanizing bath further contains at least one organic compound of water-soluble or water-dispersible polyacrylate copolymer, dicyandiamide formaldehyde, polyvinyl alcohol, or cationic polyamine in a total amount of α1 to 10 f/ 7. The method for producing a plated metal plate according to claim 6, wherein the bath contains It. (2) An aqueous solution containing silicic acid and/or silicate and/or chromic acid and/or chromate is further applied to the plated metal plate after the cathodic electrolytic treatment (B treatment) so that the amount of silicon deposited after drying is 10 to 10.
A method for manufacturing a plated metal plate according to any one of claims 6 to 7, in which the coating is coated to give a coating size of No. 400. (9) After the cathodic electrolytic treatment (B treatment), the plated metal plate is washed with water and dried, and then a resin paint is applied to form a transparent to translucent coating.Claims 6 to 8 A method for producing a plated metal plate according to any one of the following. [F] The method for manufacturing a plated metal plate according to any one of claims 6 to 9, wherein the metal plate is a steel plate or various non-ferrous metal plates.