KR20180112029A - Method for manufacturing chemical conversion treated steel sheet - Google Patents

Abstract

The chemical conversion treated steel sheet comprises a steel sheet, a plating layer formed on at least one surface of the steel sheet and containing Ni, a Zr compound formed on the plating layer in an amount of 1.0 to 150 mg / m < 2 & A chemical conversion coating layer containing 1.0 to 100 mg / m 2 of a phosphate compound and 0.10 to 30.0 mg / m 2 of an Al compound in terms of metal Al. The plating layer contains Ni in an amount of Ni of 5.0 to 3000 mg / m < 2 > in an amount of Ni, 2.0 to 200 mg / m < 2 > in terms of metal Ni and 0.10 to 10.0 g / And an island-shaped Sn plating layer is formed on the Fe-Ni-Sn alloy layer.

Description

Method for manufacturing chemical conversion treated steel sheet

The present invention relates to a chemical-treated steel sheet and a method for producing a chemical-treated steel sheet.

By using the metal continuously, corrosion may occur. Various techniques have conventionally been proposed in order to prevent corrosion occurring in the metal. Examples of the proposed technique include a technique of plating the metal plate and a technique of performing various surface treatments on the surface of the metal plate or the plating.

For example, the following Patent Document 1 discloses a method for producing a laminated body, which comprises applying a vanadium compound, at least one of a phosphoric acid and a phosphoric acid compound, and a silane compound having at least one of an epoxy group and an amino group, on a surface of an Al- And a method of forming an organic resin film containing as a main component an organic resin containing at least one of a water-soluble organic resin and a water-dispersible organic resin.

On the other hand, Ni-coated steel sheets, Sn-coated steel sheets, Sn-based alloy coated steel sheets, and the like are used for the production of metal containers for the purpose of preserving drinks and foods. The Al-Zn based alloy coated steel sheet disclosed in Patent Document 1 is a so-called sacrificial type coated steel sheet, whereas the Ni coated steel sheet, Sn coated steel sheet or Sn based alloy coated steel sheet is a so-called barrier type coated steel sheet .

When a Ni-coated steel sheet, a Sn-coated steel sheet or a Sn-based alloy coated steel sheet is used as a steel sheet for metal containers (hereinafter referred to as a steel sheet for containers) for the purpose of preserving beverages or foodstuffs, And the surface of the plated steel sheet is often subjected to a chemical conversion treatment with hexavalent chromium in order to ensure corrosion resistance and corrosion resistance. The conversion treatment using a solution containing hexavalent chromium is referred to as a chromate treatment.

However, since hexavalent chromium used in the chromate treatment is harmful to the environment, a chemically treated coating film such as a Zr-phosphorous film has been developed as an alternative to the chromate treatment performed on the conventional steel sheet for containers. For example, the following Patent Document 2 discloses a steel sheet for a container having a chemical conversion coating film containing Zr, phosphoric acid, a phenol resin, and the like.

Here, foods stored in the metal container using the steel sheet for containers include meat, vegetables, and the like. Meat or vegetables contain various proteins, but these proteins sometimes contain amino acids (S-containing cysteine, L-methionine, and L - (-) - cystine).

When heat is applied to a food containing a sulfurous amino acid during sterilization treatment, S in the sulfurous amino acid may combine with Sn or Fe contained in the steel sheet for the container to cause discoloration to black. This phenomenon is referred to as a sulphide blacking. If blackening of the sulphurization occurs, the design of the inner surface of the metal container is deteriorated, and measures are required to prevent occurrence of sulphurization.

Further, in Patent Document 3, in a solution containing at least one reaction promoting component selected from the group including Al ions, boric acid ions, Cu ions, Ca ions, metal Al and metal Cu, Zr ions and F ions , A method of producing a steel sheet for a container in which a steel sheet is immersed or electrolytic treated to form a Zr-containing coating on the surface of the steel sheet.

Japanese Patent Application Laid-Open No. 2005-290535 Japanese Patent Application Laid-Open No. 2007-284789 Japanese Unexamined Patent Publication No. 6-62521

Since the coat formed by the chromate treatment (hereinafter referred to as the chromate coat) is at least dense, the steel sheet for a vessel having a chromate film on the surface thereof has excellent corrosion resistance and blacking resistance to blackening. However, as described above, since hexavalent chromium is harmful to the environment, it is preferable that the steel sheet for the container does not contain hexavalent chromium as much as possible.

On the other hand, the organic resin coating film described in Patent Document 1 and the chemical conversion coating film described in Patent Document 2 do not contain hexavalent chromium and therefore are environmentally suitable. However, in the organic resin coating film described in Patent Document 1 and the chemical conversion coating film described in Patent Document 2, it is necessary to increase the coating amount of the coating film in order to obtain a suitable resistance to sulfur black and white color, that is, to form a dense coating film have. When the coating amount of the coating film is increased, the adhesion between the coating film and the lower coating layer of the coating film is lowered and the weldability is lowered. In addition, it is economically undesirable to increase the coating amount of the coating film.

In the method for producing a steel sheet for a container described in Patent Document 3, since the Al content in the chemical conversion coating film is small, it is sometimes difficult to obtain a suitable resistance to sulfur black and black.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a chemical conversion treated steel sheet and a chemical conversion treated steel sheet having excellent corrosion resistance and sulfur black and black degeneration even when the amount of chemical conversion coating layer adhered is small.

The present invention solves the above problems and adopts the following means to achieve the related object.

(1) A chemically treated steel sheet according to one aspect of the present invention comprises a steel sheet, a plating layer formed on at least one surface of the steel sheet and containing Ni, and a metal Zr amount of 1.0 to 150 mg / M2, a phosphoric acid compound having a P amount of 1.0 to 100 mg / m < 2 > and an Al compound having an Al amount of 0.10 to 30.0 mg / m < 2 >. The plating layer is formed of a Ni plating layer containing Ni in an amount of 5.0 to 3000 mg / m < 2 > in an amount of metal Ni, Ni of 2.0 to 200 mg / m < 2 > in terms of metal Ni and 0.10 to 10.0 g / And a island-like Sn plating layer is formed on the Fe-Ni-Sn alloy layer.

(2) In the chemically treated steel sheet described in (1) above, the chemical conversion coating layer may contain Al ₂ O ₃ in an amount of 0.10 to 30.0 mg / m 2 in terms of metal Al.

(3) The chemical conversion treated steel sheet according to (1) or (2), wherein the chemical conversion coating layer contains a Zr compound having a metal Zr content of 1.0 to 120 mg / m 2 and a P amount of 2.0 to 70.0 mg / A phosphoric acid compound and an Al compound in an amount of 0.20 to 20.0 mg / m < 2 >

(4) The chemically treated steel sheet according to any one of the above-mentioned (1) to (3), the Ni plating layer may contain Ni of 10.0 to 2000 mg / m 2 in terms of metal Ni amount.

(5) The chemically treated steel sheet according to any one of the above-mentioned (1) to (3), wherein the composite plating layer contains Ni in an amount of Ni of 5.0 to 100 mg / m 2 and Sn in an amount of 0.30 to 7.0 g / M < 2 >

(6) In the chemically treated steel sheet according to any one of the above-mentioned forms (1) to (5), the surface of the chemical conversion coating layer may not be coated with a film or a paint.

(7) A method for producing a chemically treated steel sheet according to one aspect of the present invention is a method for producing a chemically treated steel sheet, comprising the steps of: applying a Ni plating layer containing Ni in an amount of 5.0 to 3000 mg / A plating step of forming a composite plating layer containing 0.10 to 10.0 g / m < 2 > of Sn and an amount of Sn of metal in an Fe-Ni-Sn alloy layer and an island-shaped Sn plating layer on the Fe- , 10 to 20,000 ppm of F ions, 10 to 3000 ppm of phosphoric acid ions, a total of 100 to 30000 ppm of nitrate ions and sulfate ions, and 500 to 5000 ppm of Al ions, wherein the source of Al ions is (NH ₄ ) ₃ AlF ₆ and a temperature of 5 ° C or higher and lower than 90 ° C under the conditions of a current density of 1.0 to 100 A / dm ² and an electrolytic treatment time of 0.20 to 150 seconds, Alternatively, a chemical conversion coating layer may be formed on the composite plating layer Electrolytic process has the step of.

(8) The method for producing a chemically treated steel sheet according to (7), wherein the chemical conversion treatment liquid contains Zr ions of 200 to 17000 ppm, F ions of 200 to 17000 ppm, phosphate ions of 100 to 2000 ppm, Nitrate ions and sulfate ions of 1000 to 23000 ppm, and Al ions of 500 to 3000 ppm.

According to each of the above-mentioned aspects, it is possible to provide a chemical conversion treated steel sheet and a chemical conversion treated steel sheet production method which have excellent corrosion resistance and blackening resistance to blackening, even when the amount of chemical conversion coating layer adhered is small.

1A is an explanatory view schematically showing a layer structure of a chemically treated steel sheet on which a Ni plating layer is formed on one side of a steel sheet.
Fig. 1B is an explanatory view schematically showing a layer structure of a chemically treated steel sheet on which Ni plating layers are formed on both surfaces of a steel sheet.
2A is an explanatory view schematically showing an example of a chemical conversion treated steel sheet on which a composite plating layer is formed on one side of a steel sheet.
FIG. 2B is an explanatory view schematically showing an example of a chemically treated steel sheet on which a composite plating layer is formed on both surfaces of a steel sheet.
3 is a flowchart showing an example of a flow of a method of manufacturing a chemical conversion steel sheet according to an embodiment of the present invention.
4 is a graph showing the results of Example 1. Fig.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, elements having the same configuration are denoted by the same reference numerals, and redundant description is omitted.

≪ Constitution of chemical conversion treated steel sheet >

First, the structure of the chemically treated steel sheet according to the present embodiment will be described in detail with reference to Figs. 1A and 2B. Figs. 1A and 1B are explanatory diagrams schematically showing the layer structure of the chemically treated steel sheet according to the present embodiment. Fig.

1A through 2B, the chemically treated steel sheet 10 according to the present embodiment includes a steel sheet 103, one of the Ni plating layer 105 and the composite plating layer 106, a chemical conversion coating layer 107 ). One of the Ni plating layer 105 and the composite plating layer 106 and the chemical conversion coating layer 107 may be formed only on one surface of the steel sheet 103 as shown in Figs. 1A and 2A, Or may be formed on two mutually opposing surfaces of the steel sheet 103 as shown in Figs. 1B and 2B.

[About Steel Plate 103]

The steel sheet 103 is used as a base material of the converted steel sheet 10 according to the present embodiment. The steel sheet 103 used in the present embodiment is not particularly limited, and a known steel sheet used as a steel sheet for a container can be used. The production method and material of the steel sheet 103 are not particularly limited and the steel sheet 103 manufactured through a known process such as hot rolling, pickling, cold rolling, annealing, temper rolling, or the like is used It is possible to do.

The plate thickness of the steel plate 103 is preferably 0.05 to 1 mm in consideration of practicality and economical efficiency when it is used as a steel plate for a container.

[About the plating layer]

Either one of the Ni plating layer 105 and the composite plating layer 106 is formed on the surface of the steel sheet 103. The Ni plating layer 105 and the composite plating layer 106 are both a barrier type plating layer containing Ni. Here, the barrier type plating layer is formed by forming a metal film of Ni or Sn on the surface of the steel sheet 103 by using Ni or Sn, which is an electrochemically valuable metal, rather than Fe constituting the base material steel sheet 103, Is a plating layer that prevents corrosion of the steel sheet 103 by preventing it from acting on the base material.

On the other hand, the sacrificial type plating layer has a function opposite to that of the barrier type plating layer. A metal film is formed on the surface of the steel sheet 103 by using a metal (for example, Zn as in Patent Document 1) that is electrochemically lower than Fe constituting the steel sheet 103 as a base material , The metal such as Zn constituting the plating layer is first corroded than the Fe constituting the steel plate 103, thereby suppressing the corrosion of the steel plate 103.

In addition, the barrier type plating layer and the sacrificial type plating layer have different interaction with the chemical conversion coating layer 107.

Hereinafter, examples of the Ni plating layer 105 and the composite plating layer 106 according to the present embodiment will be described in detail with reference to Figs. 1A and 2B.

[When the Ni plating layer 105 is formed on the surface of the steel sheet 103]

1A, the case where the Ni plating layer 105 is formed on the surface of the steel sheet 103 will be described in detail.

The Ni plating layer 105 contains Ni and may be formed on one side of the steel sheet 103 as shown in Fig. 1A or on both sides of the steel sheet 103 as shown in Fig. 1B. In the Ni plating layer 105, it is preferable that Ni is contained in an amount of metal Ni in a range of 5.0 to 3000 mg / m 2 per one side.

Ni has excellent paint adhesion, film adhesion, corrosion resistance and weldability. In order to exhibit the above-mentioned excellent effect, it is necessary to contain Ni of not less than 5.0 mg / m < 2 >

As the content of Ni increases, the excellent effect of Ni is improved. However, if the amount of Ni is more than 3000 mg / m < 2 > per one surface, the effect is saturated, which is economically undesirable. Therefore, the content of Ni is set to 3000 mg / m 2 or less per one side in terms of metal Ni amount.

The content of Ni in the Ni plating layer is more preferably not less than 10.0 mg / m 2 and not more than 2000 mg / m 2 per one side in terms of metal Ni amount. By containing Ni of 10.0 mg / m < 2 > or more per one side in terms of metal Ni amount, the above-mentioned effect becomes more remarkable. Further, by making the content of Ni 2,000 mg / m 2 or less per one side in terms of the amount of metal Ni, it becomes possible to further reduce the manufacturing cost of the Ni plating layer 105.

The proportion of Ni in the Ni plating layer 105 is 50% by mass or more in terms of the amount of metal Ni in the center portion of the Ni plating layer 105. [ Preferably, the proportion of Ni in the Ni plating layer 105 is 70 mass% or more in terms of the amount of metal Ni in the center portion of the Ni plating layer 105. [

The Ni plating layer 105 may contain Fe in an amount of 1.0 to 2000 mg / m < 2 > The Ni plating layer 105 may contain inevitable impurities which may be mixed in the manufacturing process or the like.

[When the composite plating layer 106 is formed on the surface of the steel sheet 103]

A case where a composite plating layer 106 containing Ni and Sn is formed on the surface of the steel sheet 103 will be described in detail with reference to Figs. 2A and 2B.

The composite plating layer 106 according to the present embodiment may be formed on one surface of the steel sheet 103 as shown in Fig. 2A or on both surfaces of the steel sheet 103 as shown in Fig. 2B. The composite plating layer 106 has an Fe-Ni-Sn alloy layer 105d and a island-shaped Sn plating layer 105e formed on the Fe-Ni-Sn alloy layer 105d.

In order to form the composite plating layer 106, a Ni plating layer (not shown) is first formed on the steel sheet 103. The Ni plating layer (not shown) contains Ni or an Fe-Ni alloy and is formed to secure the corrosion resistance of the converted steel sheet 10.

The effect of improving the corrosion resistance of the converted steel sheet 10 by Ni is determined by the amount of Ni contained in the composite plating layer 106. [ If the amount of Ni in the composite plating layer 106 is 2 mg / m < 2 > or more per one side in terms of the amount of metal Ni, the effect of improving the corrosion resistance by Ni is expressed.

On the other hand, as the amount of Ni in the composite plating layer 106 increases, the effect of improving the corrosion resistance increases. However, when the amount of Ni in the composite plating layer 106 exceeds 200 mg / The effect saturates. Since Ni is an expensive metal, when the amount of Ni in the composite plating layer 106 exceeds 200 mg / m 2 per one surface in terms of the amount of metal Ni, it is economically undesirable.

Therefore, the amount of Ni in the composite plating layer 106 is 2.0 mg / m 2 to 200 mg / m 2 per one side in terms of metal Ni amount. The amount of Ni in the composite plating layer 106 is more preferably 5.0 mg / m2 to 100 mg / m2 per one side in terms of the amount of metal Ni. When the composite plating layer 106 contains Ni of 5.0 mg / m < 2 > or more per one side in terms of metal Ni, the effect of improving the corrosion resistance by Ni is more effectively exhibited. Further, by making the amount of Ni in the composite plating layer 106 equal to or less than 100 mg / m < 2 > per one side in terms of the amount of metal Ni, the manufacturing cost can be further reduced.

After the above-described Ni plating layer (not shown) is formed, a Sn plating layer (not shown) is formed. In addition, the Sn plating layer (not shown) in this embodiment may be composed only of Sn, and may contain impurities and trace elements in addition to Sn.

A Sn plating layer (not shown) is formed to secure the corrosion resistance and weldability of the converted steel sheet 10. Sn not only has high corrosion resistance of Sn itself, but also Sn alloys formed by melt-melting treatment have excellent corrosion resistance and weldability.

Ni-Sn alloy layer 105d is formed on the steel sheet 103 by melting melt processing after the Sn-plated layer (not shown) is formed and the island-like Sn A plating layer 105e is formed.

In the island-shaped Sn-plated layer 105e, Sn exists in a island shape, and the Fe-Ni-Sn alloy layer 105d as a lower layer is exposed in the sea. The film-like Sn plating layer 105e secures film adhesion and paint adhesion of the chemical conversion treated steel sheet 10.

In the heat treatment after the film laminate or the coating of the coating material, the chemical-treated steel sheet 10 may be heated to the melting point of Sn (232 캜) or higher. Unlike the present embodiment, when Sn covers the entire surface of the Fe-Ni-Sn alloy layer 105d, Sn is melted or oxidized by the above-described heat treatment, and the film adhesion of the converted steel sheet 10 and / There is a possibility that the paint adhesion can not be ensured.

The composite plating layer 106 according to the present embodiment contains Sn of 0.10 to 10.0 g / m < 2 >

Sn has excellent processability, weldability and corrosion resistance, and is subjected to melt-melting treatment after Sn plating to further improve the corrosion resistance of the converted steel sheet 10 and improve the surface appearance (mirror-surface appearance) of the converted steel sheet 10 It is possible to make it more preferable. In order to exhibit the above-described effect, it is necessary that the composite plating layer 106 contains Sn of 0.10 g / m < 2 >

As the content of Sn in the composite plating layer 106 is increased, the workability, weldability and corrosion resistance of the converted steel sheet 10 are improved. However, if the content of Sn exceeds 10.0 g / The effect described above is saturated. When the content of Sn exceeds 10.0 g / m < 2 > per one side in terms of the amount of metal Sn, it is economically undesirable. For the above reason, the content of Sn in the composite plating layer 106 is set to 10.0 g / m 2 or less per one side in terms of the amount of metal Sn.

The content of Sn in the composite plating layer 106 is more preferably from 0.30 g / m 2 to 7.0 g / m 2 per one side in terms of the amount of metal Sn. Since the composite plating layer 106 contains Sn of 0.30 g / m < 2 > or more per one surface in terms of the amount of metal Sn, the above-described effect of Sn can be more reliably exhibited. Further, since the composite plating layer 106 contains Sn of 7.0 g / m < 2 > or less per one side in the amount of metal Sn, the manufacturing cost can be further reduced.

The total amount of Ni metal Ni and Sn metal Sn contained in composite plating layer 106 is 50 mass% or more of composite plating layer 106. Preferably, the total amount of the Ni metal Ni and the Sn Sn metal contained in the composite plating layer 106 is 70% by mass or more of the composite plating layer 106.

The composite plating layer 106 may contain Fe in an amount of 1.0 to 3500 mg / m < 2 > per one side, in addition to Ni and Sn as described above. The composite plating layer 106 may contain inevitable impurities that may be mixed in a manufacturing process or the like.

When the steel sheet 103 on which the Ni plating layer 105 or the composite plating layer 106 is formed on the surface is used as the steel sheet for the container, a film is laminated on the surface of the Ni plating layer 105 or the composite plating layer 106, Even when applied, it is difficult to prevent blackening of the sulphide. It is considered that S contained in the contents such as beverages and foods contained in the contents is combined with Ni or Sn in the plating layer 105 to form black NiS, SnS, SnS ₂ and the like.

In addition, S is contained in beverages and foods as components of sulfuric amino acids such as L-cysteine, L - (-) - cystine and L-methionine.

When the Ni plating layer 105 or the composite plating layer 106 is not densely formed, a part of the steel sheet 103 as a base material is exposed. In such a case, Fe in the steel sheet 103 may be combined with S contained in beverages, foods, etc., and black FeS, Fe ₂ S ₃ and Fe ₂ S may be formed.

A chromate film has been formed mainly on the surface of the Ni plating layer 105 or the composite plating layer 106 so far so as to reduce the blackness caused by the NiS, SnS, SnS ₂ , FeS, Fe ₂ S ₃ , Fe ₂ S, .

Treated steel sheet 10 according to the present embodiment has a structure in which a Zr compound, a phosphoric acid compound, and a Zr compound are used as an upper layer of the Ni plating layer 105 or the composite plating layer 106 as a substitute for a conventional chromate coating, A chemical conversion coating layer 107 containing an Al compound is formed.

[Regarding the chemical conversion coating layer 107]

1A and 2B, a chemical conversion coating layer 107 is formed on the Ni plating layer 105 or the composite plating layer 106 in the chemically treated steel sheet 10 of the present embodiment. The chemical conversion coating layer 107 is a composite coating layer mainly composed of a Zr compound and is composed of a Zr compound having a metal Zr content of 1.0 to 150 mg / m 2 per one side, a phosphoric acid compound having a P amount of 1.0 to 100 mg / And an Al compound in an amount of 0.10 to 30.0 mg / m < 2 >

Further, in the present embodiment, the composite coating layer refers to a coating layer in which the Zr compound, the phosphoric acid compound, and the Al compound are not mixed completely but exist in a partially mixed state.

In the case where three coating films of a Zr coating containing a Zr compound, a phosphoric acid coating containing a phosphoric acid compound and an Al coating containing an Al compound are overlaid on the Ni plating layer 105 or the composite plating layer 106, Although some effect is obtained, it is not practical enough. However, since the Zr compound, the phosphoric acid compound and the Al compound exist in a partially mixed state in the chemical conversion coating layer 107 as in the present embodiment, as compared with the case where three coatings are formed as described above, Excellent corrosion resistance and adhesion can be obtained.

The Zr compound contained in the chemical conversion coating layer 107 according to the present embodiment has a function of improving corrosion resistance, adhesion, and processing adhesion. Examples of the Zr compound according to the present embodiment include Zr oxide, Zr phosphate, Zr hydroxide and Zr fluoride, and the chemical conversion coating layer 107 contains a plurality of Zr compounds described above. Preferred combinations of Zr compounds are oxidized Zr, phosphoric Zr and fluorinated Zr.

When the content of the Zr compound contained in the chemical conversion coating layer 107 is 1.0 mg / m < 2 > or more per one surface in terms of the amount of metal Zr, practically suitable corrosion resistance, adhesion and processing adhesion are secured.

On the other hand, with an increase in the content of the Zr compound, the corrosion resistance, the adhesion and the processing adhesion are improved. However, if the content of the Zr compound exceeds 150 mg / m < 2 > per one side in terms of the amount of metal Zr, the chemical conversion coating layer 107 becomes excessively thick and mainly causes cohesive failure, The adhesion to the copper plating layer 105 or the composite plating layer 106 is lowered, and the electrical resistance is increased and the weldability is lowered. If the content of the Zr compound exceeds 150 mg / m 2 in terms of the amount of the metal Zr, the appearance may become uneven due to uneven adhesion of the chemical conversion coating layer 107.

Therefore, the content of the Zr compound (that is, the content of Zr) in the chemical conversion coating layer 107 according to the present embodiment is 1.0 mg / m2 to 150 mg / m2 per one side in terms of the amount of metal Zr. The content of the Zr compound is more preferably 1.0 to 120 mg / m 2 per one side in terms of the amount of the metal Zr. By making the amount of the metal Zr to be 120 g / m 2 or less, the manufacturing cost of the chemical conversion coating layer 107 can be further reduced.

The chemical conversion coating layer 107 further comprises one or more kinds of phosphoric acid compounds in addition to the above Zr compound.

The phosphate compound according to the present embodiment has a function of improving corrosion resistance, adhesion, and processing adhesion. Examples of the phosphate compound according to the present embodiment include phosphoric acid Fe, phosphoric acid Ni (phosphoric acid), and phosphoric acid, which are formed by reacting phosphoric acid ions with a compound contained in the steel sheet 103, the Ni plating layer 105 or the composite plating layer 106 and the chemical conversion coating layer 107 , Sn phosphate, Zr phosphate, and Al phosphate. The chemical conversion coating layer 107 may contain one or more of the above-mentioned phosphate compounds.

The higher the content of the phosphoric acid compound contained in the chemical conversion coating layer 107, the more the corrosion resistance, the adhesion and the processing adhesion of the chemical conversion treated steel sheet 10 are improved. Specifically, when the content of the phosphoric acid compound in the chemical conversion coating layer 107 is 1.0 mg / m < 2 > or more in terms of the amount of P, practically suitable corrosion resistance, adhesion and processing adhesion are secured.

On the other hand, as the content of the phosphoric acid compound increases, the corrosion resistance, the adhesion and the processing adhesion are also improved. However, if the content of the phosphoric acid compound exceeds 100 mg / m 2 per one surface in terms of the amount of P, the chemical conversion coating layer 107 is excessively The cohesion failure mainly occurs and the adhesion of the chemical conversion coating layer 107 to the Ni plating layer 105 or the composite plating layer 106 is lowered and the electrical resistance is increased and the weldability is lowered. If the content of the phosphoric acid compound exceeds 100 mg / m < 2 > per one surface in terms of P amount, the appearance may become uneven due to uneven adhesion of the chemical conversion coating layer 107.

Therefore, the content of the phosphate compound in the chemical conversion coating layer 107 according to the present embodiment is 1.0 mg / m 2 to 100 mg / m 2 per one surface.

The content of the phosphate compound in the chemical conversion coating layer 107 is more preferably 2.0 to 70.0 mg / m < 2 > When the content of the phosphate compound in the chemical conversion coating layer 107 is 2.0 mg / m < 2 > per one surface in terms of the amount of P, it is possible to obtain more preferable resistance to sulfurization and blackening. Further, by making the content of the phosphoric acid compound in the chemical conversion coating layer 107 70.0 mg / m 2 or less per one surface in terms of P amount, it is possible to further reduce the manufacturing cost of the chemical conversion coating layer 107.

The chemical conversion coating layer 107 further contains an Al compound in addition to the Zr compound and the phosphoric acid compound described above. The Al compound in the chemical conversion coating layer 107 is mainly present as Al oxide in the chemical conversion coating layer 107. Al oxide reinforces coating defects in the chemical conversion coating layer 107 containing Zr as a main component, so that the chemical conversion treated steel sheet 10 can obtain excellent sulfurization blackening resistance.

Since the chemical conversion coating layer 107 mainly composed of Zr is an extremely uniform coating, the amount of the Al compound to be added to the chemical conversion coating layer 107 in order to reinforce coating defects is 0.10 mg / m < 2 > . When the content of the Al compound is 0.10 mg / m < 2 > or more per one surface in terms of the amount of the metal Al, it is possible to suitably improve the resistance to sulfidization of the chemical conversion treated steel sheet 10.

On the other hand, as the content of the Al compound in the chemical conversion coating layer 107 increases, the resistance to blacking of the sulfide is also improved. However, when the content of the Al compound exceeds 30.0 mg / The denaturation is saturated and it is economically undesirable. Therefore, the content of the Al compound contained in the chemical conversion coating layer 107 is set to 30.0 mg / m 2 or less per one side in terms of the amount of the metal Al.

The content of the Al compound in the chemical conversion coating layer 107 is more preferably from 0.20 to 20.0 mg / m 2 per one side in terms of metal Al. By making the content of the Al compound 0.20 mg / m < 2 > or more per one surface in terms of the amount of the metal Al, it is possible to appropriately improve the resistance to blackening of the yellowing. Further, by making the content of the Al compound 20.0 mg / m 2 or less per one side in terms of the amount of the metal Al, it becomes possible to further reduce the manufacturing cost of the chemical conversion coating layer 107.

The content of Al oxide (Al ₂ O ₃ ) in the chemical conversion coating layer 107 is preferably 0.10 to 30.0 mg / m 2 in terms of the amount of metal Al. When the content of Al oxide in the chemical conversion coating layer 107 is in the above-described range, coating defects of the chemical conversion coating layer 107 are appropriately reinforced, and excellent sulfurization blackening can be obtained.

Also, by containing the Al compound in the chemical conversion coating layer 107, it is possible to reduce the content of the phosphoric acid compound which improves the resistance to blackening of the sulfur black as in the case of Al.

Among the phosphoric acid compounds contained in the chemical conversion coating layer 107, the phosphoric acid Zr generated by the reaction of the phosphate ion with the Zr ion is precipitated when a large amount exists in the chemical conversion treatment solution used for forming the chemical conversion coating layer 107 , And the chemical conversion treatment solution becomes cloudy.

Here, the Al compound contributes to the improvement of the resistance to sulphurisation of the black color rather than the phosphoric acid compound. Therefore, by containing the Al compound in the chemical conversion coating layer 107, it is possible to reduce the content of the phosphoric acid compound which causes the clouding of the chemical conversion solution while appropriately improving the sulfurization blackening.

Further, by reducing the content of the phosphoric acid compound, it is possible to reduce the amount of F ions that interfere with the binding of Zr to phosphoric acid and the binding of Al to phosphoric acid. As a result, since Zr can be deposited more easily, the electrolysis efficiency for forming the chemical conversion coating layer 107 can be improved.

The chemical conversion coating layer 107 may contain, in addition to the Zr compound, the phosphoric acid compound and the Al compound, the inevitable impurities which are mixed in the manufacturing process and the like. When the chemical conversion coating layer 107 contains Cr, the upper limit of the Cr content is 2.0 mg / m 2.

The chemical conversion treated steel sheet 10 according to the present embodiment exhibits excellent resistance to sulfur black and black even when the amount of the chemical conversion coating layer 107 is reduced.

For example, a paint is attached to the surface of the chemical conversion treated steel sheet 10 and baked to form a coated film. Treated steel plate 10 having a coating film formed on its surface was mounted and fixed as a lid on the entrance of a heat-resistant bottle holding a 0.6 mass% L-cysteine solution boiled for one hour, Heat treatment for a minute is carried out. When the chemically treated steel sheet 10 according to the present embodiment is used, the appearance of the contact portion of the heat-treated steel sheet 10 after the above-described heat treatment is observed. When the chemical-treated steel sheet 10 according to the present embodiment is used, .

As described above, the chemical conversion treated steel sheet 10 according to the present embodiment has excellent corrosion resistance and sulfur black and black coloration. Therefore, even when the surface of the chemical conversion coating layer 107 is not coated with a film or paint, the chemical conversion treated steel sheet 10 can be used as a steel sheet for a container.

≪ About the layer structure of chemical conversion treated steel sheet 10 >

The chemical conversion treated steel sheet 10 has the Ni plating layer 105 or the composite plating layer 106 on the steel sheet 103 and the chemical conversion coating layer 107 on the Ni plating layer 105 or the composite plating layer 106 . That is, in the chemically treated steel sheet 10, the steel sheet 103 is in contact with the Ni plating layer 105 or the composite plating layer 106, and the steel sheet 103 is bonded to the Ni plating layer 105 or the composite plating layer 106 It has no other layer. Similarly, the Ni plating layer 105 or the composite plating layer 106 and the chemical conversion coating layer 107 are in contact with each other and the Ni plating layer 105 or the composite plating layer 106 and the chemical conversion coating layer 107 ). ≪ / RTI >

≪ Method of measuring content of ingredients >

The amount of metal Ni and the amount of metal Sn in the Ni plating layer 105 and the composite plating layer 106 can be measured by, for example, a fluorescent X-ray method. In this case, a calibration curve relating to the amount of metal Ni is prepared in advance using a sample of a metal Ni amount, and the amount of metal Ni is relatively specified using the prepared calibration curve. Similarly to the amount of metal Sn, a calibration curve relating to the amount of metal Sn is prepared in advance by using a sample of a known amount of metal Sn, and the amount of metal Sn is specified relatively using the prepared calibration curve.

The amount of metal Zr, P amount and metal Al in the chemical conversion coating layer 107 can be measured by, for example, quantitative analysis such as fluorescent X-ray analysis. Further, it is possible to specify which compound exists in the chemical conversion coating layer 107 by performing analysis by X-ray photoelectron spectroscopy (XPS).

The content of Al ₂ O _{3 in} the chemical conversion coating layer 107 is first determined by X-ray photoelectron spectroscopy (XPS) to a peak intensity ratio of Al ₂ O ₃ , metal Al and other Al compounds to I ask. Then, the content of Al ₂ O _{3 in} the chemical conversion coating layer 107 is calculated from the peak intensity ratio determined by XPS and the total amount of metal Al determined by quantitative analysis such as fluorescent X-ray analysis as described above.

In addition, the measurement method of each component is not limited to the above-described method, and a known measurement method can be applied.

≪ Manufacturing method of chemical conversion treated steel sheet 10 >

Next, a manufacturing method of the chemically processed steel sheet 10 according to the present embodiment will be described in detail with reference to FIG. Fig. 3 is a flowchart for explaining an example of the flow of the method of manufacturing the chemically treated steel sheet 10 according to the present embodiment.

[Pretreatment process]

In the method of manufacturing the chemical conversion treated steel sheet 10 according to the present embodiment, first, a known pretreatment is performed on the steel sheet 103 as necessary (step S101).

[Plating process]

Thereafter, either the Ni plating layer 105 or the composite plating layer 106 is formed on the surface of the steel sheet 103 (step S103).

When the Ni plating layer 105 is formed on the surface of the steel sheet 103, a known technique such as an electroplating method or a vacuum deposition method can be used. In order to form an Fe-Ni diffusion layer (not shown) at the interface between the steel sheet 103 and the Ni plating layer 105, a heat treatment may be performed after the Ni plating layer 105 is formed.

When the composite plating layer 106 having the Fe-Ni-Sn alloy layer 105d and the island-shaped Sn plating layer 105e is formed on the surface of the steel sheet 103, the Ni or Fe-Ni alloy (Reflow treatment) after forming a Ni plating layer (not shown) including a Sn plating layer (not shown) on the Ni plating layer (not shown) and further forming a Sn plating layer (not shown) on the Ni plating layer

That is, the Fe of the steel plate 103, the Ni of the Ni plating layer (not shown) and the Sn of a part of the Sn plating layer (not shown) are alloyed by the melt-melt processing to form the Fe-Ni-Sn alloy layer 105d And the remainder of the Sn plating layer becomes island-like, so that the island-like Sn plating layer 105e is formed.

As a method of forming a Ni plating layer (not shown) containing Ni or an Fe-Ni alloy, a general electroplating method (for example, a cathode electrolysis method) can be used.

The method of forming the Sn plating layer (not shown) is also not particularly limited, and for example, a well-known electroplating method, a method of immersing the molten Sn in the steel sheet 103 and plating can be used.

When a Ni plating layer (not shown) is formed by the diffusion plating method, the surface of the steel sheet 103 is subjected to Ni plating, followed by diffusion treatment for forming a diffusion layer in the annealing furnace. The nitriding treatment may be performed before or after the diffusion treatment or simultaneously with the diffusion treatment. Even when the nitriding treatment is performed, the effect of the Ni in the Ni plating layer (not shown) in the present embodiment and the effect of the nitriding treatment do not interfere, and both of these effects can be exerted.

After the formation of a Sn plating layer (not shown), molten lime treatment (reflow treatment) is performed. The melted Sn is alloyed with Fe in the steel sheet 103 and Ni in the Ni plating layer (not shown) to form the Fe-Ni-Sn alloy layer 105d and the island- A Sn plating layer 105e is formed. The island-shaped Sn-plated layer 105e can be formed by suitably controlling the molten slag treatment.

[Electrolytic Treatment Process]

After forming either the Ni plating layer 105 or the composite plating layer 106, a chemical conversion coating layer 107 is formed by electrolytic treatment (step S105).

The chemical conversion coating layer 107 is formed by an electrolytic treatment (for example, a cathode electrolytic treatment). The chemical liquor used for forming the chemical conversion coating layer 107 by electrolytic treatment contains Zr ions of 10 ppm or more and 20000 ppm or less, F ions of 10 ppm or more and 20000 ppm or less, and phosphate ions of 10 ppm or more and 3000 ppm or less in total, Nitrate ions and sulfate ions of not less than 30000 ppm and Al ions of not less than 500 ppm and not more than 5000 ppm. Also, (NH ₄ ) ₃ AlF ₆ is used as a source of Al ions in the chemical conversion solution.

The nitrate ion and the sulfate ion may be contained in the chemical liquor in a total amount of 10 ppm or more and 3,000 ppm or less in total of the positive ion. The nitrate ion and the sulfate ion may be included in the chemical liquor, Only one of them may be included in the chemical conversion solution.

The chemical treatment liquid preferably contains 200 ppm or more and 17000 ppm or less of Zr ions, 200 ppm or more and 17000 ppm or less of F ions, 100 ppm or more and 2,000 ppm or less of phosphate ions, nitrate ions and sulfate ions in total of 1000 ppm or more and 23000 ppm or less, And more preferably not more than 3,000 Al ions.

When the concentration of the Zr ions is 200 ppm or more, it is possible to more reliably prevent a decrease in the amount of Zr adhered. In addition, by setting the concentration of the F ion to 200 ppm or more, clouding of the chemical conversion coating layer 107 accompanying precipitation of the phosphate can be more reliably prevented.

Similarly, when the concentration of the phosphate ions is 100 ppm or more, clouding of the chemical conversion coating layer 107 accompanying precipitation of the phosphate can be more reliably prevented. Further, by setting the concentration of at least one of the nitrate ion and the sulfate ion to 1000 ppm or more, deterioration of the adhesion efficiency of the chemical conversion coating layer 107 can be more reliably prevented. Further, by increasing the concentration of Al ions to 500 ppm or more, it is possible to more reliably realize the effect of improving the resistance to the oxidation of yellowing.

Further, by setting the upper limit value of each component of the chemical liquor to the same value as above, the manufacturing cost of the chemical conversion coating layer 107 can be more reliably reduced.

It is preferable that the temperature of the chemical treatment liquid is 5 占 폚 or more and less than 90 占 폚. When the temperature of the chemical conversion solution is less than 5 占 폚, formation efficiency of the chemical conversion coating layer 107 is poor and it is not economical. In addition, when the temperature of the chemical liquor is 90 DEG C or higher, the formed structure of the chemical conversion coating layer 107 is uneven, and defects such as cracks and micro cracks are generated, and these defects become a starting point of corrosion, It is not preferable.

In addition, the temperature of the chemical conversion solution must be set so that the reactivity of the chemical conversion solution at the interface is enhanced and the adhesion between the Ni plating layer 105 and the composite plating layer 106 Is higher than the surface temperature of the formed steel plate 103.

The current density at the time of electrolytic treatment is preferably 1.0 A / dm ² or more and 100 A / dm ² or less. When the current density is less than 1.0 A / dm ² , the deposition amount of the chemical conversion coating layer 107 is lowered and the electrolytic treatment time may become longer, which is not preferable. When the current density is more than 100 A / dm ² , the amount of the chemical conversion coating layer 107 to be deposited becomes excessive, and the chemical conversion coating layer 107 having the insufficient adhesion among the converted chemical conversion coating layers 107 formed is subjected to electrolytic treatment (Peeled off) in a cleaning process by washing with water or the like afterwards.

The electrolysis treatment time (electrolysis treatment time) is preferably 0.20 second or more and 150 seconds or less. When the electrolytic treatment time is less than 0.20 sec, the amount of the chemical conversion coating layer 107 adhered decreases, and desired performance is not obtained, which is not preferable. On the other hand, if the electrolytic treatment time is more than 150 seconds, the amount of the chemical conversion coating layer 107 is excessively increased, and the chemical conversion coating layer 107 having the insufficient adhesion among the converted chemical conversion coating layers 107 formed thereon, (Peeled off) in a cleaning process by washing with water or the like, which is not preferable.

The pH of the chemical treatment liquid is preferably in the range of 3.1 to 3.7, more preferably about 3.5. If necessary, nitric acid, ammonia, or the like may be added to adjust the pH of the chemical conversion solution.

The chemical conversion coating layer 107 according to the present embodiment can be formed on the surface of either the Ni plating layer 105 or the composite plating layer 106 by electrolytic treatment under the above conditions.

Further, in forming the chemical conversion coating layer according to the present embodiment, tannic acid may be further added to the chemical liquor used in the electrolytic treatment. By adding tannic acid to the chemical liquor, tannic acid reacts with Fe in the steel sheet 103 to form a film of tannic acid Fe on the surface of the steel sheet 103. The coating of tannic acid Fe is preferable because it improves resistance to corrosion and adhesion.

As the solvent of the chemical treatment liquid, for example, deionized water, distilled water and the like can be used. The preferable electrical conductivity of the solvent of the chemical conversion solution is 10 μS / cm or less, more preferably 5 μS / cm or less, and further preferably 3 μS / cm or less. However, the solvent of the chemical conversion treatment liquid is not limited to this, and it can be appropriately selected depending on the material to be dissolved, the formation method, the formation condition of the chemical conversion coating layer 107, and the like. However, it is preferable to use deionized water or distilled water in terms of industrial productivity, cost, and environment based on stable deposition amount stability of each component.

As the supply source of Zr, for example, a Zr complex such as H ₂ ZrF ₆ can be used. Zr in the Zr complex is present in the chemical liquor as Zr ^{4 +} by a hydrolysis reaction accompanied by an increase in pH at the cathode electrode interface. Such Zr ions form a compound such as ZrO ₂ or Zr ₃ (PO ₄ ) ₄ by performing a dehydration condensation reaction with a hydroxyl group (-OH) present on the metal surface in the chemical liquor.

Further, (NH ₄ ) ₃ AlF ₆ is used as a source of Al in the chemical treatment liquid. (NH ₄ ) ₃ AlF ₆ is used as a source of Al, Al is present in the chemical conversion solution in a state of forming a complex with F (hereinafter referred to as AlF complex). Al in the AlF complex is precipitated together with Zr in the electrolytic treatment step to form the converted coating layer 107, which contributes to the resistance to blackening of the yellowing as described above.

Al, like Zr, is present as a cation in the chemical liquor. Therefore, by using (NH ₄ ) ₃ AlF ₆ as a supply source of Al, it becomes possible to supply Al to the chemical conversion solution without increasing the concentration of phosphate ions in the chemical conversion solution.

On the other hand, when Al ₂ (SO ₄ ) ₃ or the like is used as a source of Al as in Patent Document 3, since AlF complex is not formed, Al is not appropriately precipitated during the electrolytic treatment step, 107) is very small. In this case, the chemical conversion coating layer 107 is not preferable because it does not have suitable resistance to sulphuric blackening.

[Post-treatment process]

Then, if necessary, known post-processing is performed on the steel plate 103 on which the Ni plating layer 105, the composite plating layer 106, and the chemical conversion coating layer 107 are formed (step S107).

The treated steel sheet 10 according to the present embodiment is produced by performing the treatment in the above-described flow.

In the above description, the case where the chemical conversion coating layer 107 is formed on the Ni plating layer 105 or the composite plating layer 106 by the electrolytic treatment has been described. However, If allowed, the chemical conversion coating layer 107 may be formed by an immersion treatment instead of an electrolytic treatment.

Example

Hereinafter, a method of producing a chemically treated steel sheet and a chemically treated steel sheet according to embodiments of the present invention will be described in detail with reference to examples. It should be noted that the following embodiments are only examples of the method for producing a chemically treated steel sheet and a chemically treated steel sheet according to the embodiments of the present invention and the method for producing a chemically treated steel sheet and a chemically- .

(Example 1)

In Example 1, the content of the Al compound was changed without changing the content of the Zr compound and the phosphoric acid compound in the chemical conversion coating layer, and verification was made as to how the yellowing black discoloration changed.

In Example 1, a steel sheet generally used as a steel sheet for a container was used as a base material, and a Ni plating layer was formed as a plating layer. The content of Ni in the Ni plating layer was set to 1000 mg / m < 2 > Then, the concentration of the Al compound in the chemical conversion coating layer was changed for each sample to form a chemical conversion coating layer, and a plurality of samples were produced. Here, in each sample, the content of the Zr compound was 8 mg / m 2 per one side of the amount of the metal Zr, and the content of the phosphate compound was 3 mg / m 2 per side in the amount of P.

The evaluation of the sulphide coloration was carried out as follows. First, a 0.6 mass% L-cysteine solution boiled for one hour was placed in a heat-resistant bottle, and the above sample (? 40 mm) was placed and fixed as a cover at the entrance of the heat-resistant bottle. Subsequently, heat treatment (retort treatment) at 110 캜 for 15 minutes was carried out in the crack furnace for a heat-resistant bottle which was covered as described above. Thereafter, in each sample, the appearance of the contact portion with the heat-resistant bottle was observed, and evaluation was made in ten steps based on the following criteria. In addition, in the following evaluation criteria, if the score is 5 or more, it can withstand actual use.

≪ Evaluation Criteria of Sulfur Black Degeneration >

The ratio of the area not changed to black among the contact area of the sample and 0.6 mass% L-cysteine liquid was rated 1 to 10.

10 points: 100% to 90% or more

9 points: Less than 90% Less than 80%

8 points: Less than 80% Less than 70%

7 points: Less than 70% Less than 60%

6 points: Less than 60% Less than 50%

5 points: Less than 50% Less than 40%

4 points: Less than 40% Less than 30%

3 points: Less than 30% Less than 20%

2 points: Less than 20% Less than 10%

1 point: less than 10% less than 0%

The obtained evaluation results are shown in Fig. In Fig. 4, the abscissa indicates the content of the Al compound (the amount of the metal Al) in the chemical conversion coating layer in each sample, and the ordinate indicates the evaluation result of the resistance to sulphate yellowing.

As shown in Fig. 4, when the content of the Al compound was less than 0.1 mg / m < 2 > per one side in terms of the amount of metal Al, On the other hand, when the content of the Al compound is 0.1 mg / m < 2 > or more per one surface in terms of the amount of the metal Al, it is clear that the evaluation result of the resistance to sulphurisation is at least 7,

From this result, it can be seen that the sulfided black degeneration of the chemically treated steel sheet having the chemical conversion coating is dramatically improved by containing a predetermined amount of the Al compound in the chemical conversion coating layer.

(Example 2)

Subsequently, it was verified how the resistance to blackening of the sulfide was changed by the kind of the plating layer and the content of each component contained in the chemical conversion coating layer. In Examples and Comparative Examples except for Comparative Example a5, the plating layer is either a Ni plating layer or a composite plating layer. On the other hand, in Comparative Example a5, a composite plating layer was formed on the Ni plating layer (two plating layers were formed).

(NH ₄ ) ₃ AlF ₆ was used as a source of Al ions in the inventive examples A1 to A31 and comparative examples a1 to a6. In Comparative examples a7 and a8, Al ₂ (SO ₄ ) ₃ was used to form a chemical conversion coating layer.

The amount of metal Ni and the amount of metal Sn contained in the plating layer and the amount of metal Zr, P amount and metal Al contained in the chemical conversion coating layer were measured by fluorescent X-ray analysis.

The content of Al ₂ O ₃ in the chemical conversion film layer was first determined by X-ray photoelectron spectroscopy (XPS) to determine the peak intensity ratio of Al ₂ O ₃ , metal Al and other Al compounds. Then, the content of Al ₂ O _{3 in} the chemical conversion coating layer was calculated from the peak intensity ratio determined by XPS and the total amount of metal Al determined by quantitative analysis such as fluorescent X-ray analysis as described above.

The measurement results are shown in Table 1 below.

≪ Evaluation of corrosion resistance &

The corrosion resistance test liquid was 3% acetic acid. The steel sheet was cut to a diameter of 35 mm and fixed on the entrance of the heat-resistant bottle into which the corrosion resistance test liquid was placed. After the heat treatment at 121 占 폚 for 60 minutes, the corrosion resistance was evaluated by the ratio of the area where the corrosion resistance test liquid contacted with the Ni-plated steel sheet (the area of the entrance of the heat resistance).

More specifically, the test piece was rated from 1 to 10 in terms of the ratio of the corrosion area to the area in contact with the test solution. Further, in the following evaluation criteria, if the score is 5 or more, it can withstand actual use.

10 points: 100% to 90% or more

9 points: Less than 90% Less than 80%

8 points: Less than 80% Less than 70%

7 points: Less than 70% Less than 60%

6 points: Less than 60% Less than 50%

5 points: Less than 50% Less than 40%

4 points: Less than 40% Less than 30%

3 points: Less than 30% Less than 20%

2 points: Less than 20% Less than 10%

1 point: less than 10% less than 0%

In the items of the corrosion resistance evaluation, 10 points to 9 points were indicated as "Very Good", 8 points to 5 points as "Good", and 4 points or less as "Not Good".

≪ Evaluation of Sulfur Black Deformation &

The evaluation of the sulphide coloration was carried out as follows. The 0.6 mass% L-cysteine solution boiled for one hour was placed in a heat-resistant bottle, and the sample (? 40 mm) as a cover was placed and fixed at the entrance of the heat-resistant bottle. Heat treatment (retort treatment) was performed in a crack furnace at 110 DEG C for 15 minutes against a heat-resistant bottle covered with a sample. Thereafter, in each of the samples, the appearance of the contact portion with the heat-resistant bottle was observed, and 10-step evaluation was carried out based on the same criteria as above. In Table 2 shown below, 10 points to 8 points are indicated as " Very Good ", 7 points to 5 points are indicated as " Good "

The obtained results are shown in Table 2 below.

As shown in Table 2, all of Inventive Examples A1 to A31 had excellent corrosion resistance and sulfur black coloration. On the other hand, in Comparative Examples a1 to a8, either the corrosion resistance or the blacking resistance was deteriorated. In Comparative Examples a7 and a8 in which Al ₂ (SO ₄ ) ₃ was used as a source of Al ions, the amount of Al and Al ₂ O ₃ was remarkably small, and the resistance to yellowing was also "Not Good".

(Example 3)

Subsequently, it was verified how the resistance to light yellowing was changed according to the kind of the plating layer and the content of each component contained in the chemical conversion coating layer.

Each sample having the Ni plating layer or the composite plating layer shown in Table 3 was subjected to a chemical treatment under the conditions shown in Table 4 (conditions of the chemical treatment solution and electrolytic treatment conditions). Table 5 shows the amount of metal Zr, the amount of P, the amount of metal Al and the amount of Al ₂ O _{3 in} the chemical conversion coating layer formed on the plating layer of each sample.

The samples having the plated layer and the chemically treated coat layer were evaluated for corrosion resistance and blackening resistance to sulfur black as in Example 2. The results are shown in Table 5.

(NH ₄ ) ₃ AlF ₆ was used as the source of Al ions, while in Comparative Examples b 9 and b ₁₀ , Al ₂ (SO ₄ ) ₂ was used as the source of Al ions, while the inventive examples B 1 to B 31 and Comparative Examples b 1 to b ₈ used ₃ was used to form a chemical conversion coating layer.

As shown in Table 5, all of the present invention examples B1 to B31 produced by the method for producing a chemical conversion treated steel sheet according to the present embodiment all had excellent corrosion resistance and sulfur black coloration. On the other hand, all of the comparative examples b1 to b10 had excellent corrosion resistance, but the yellowing and blackening were separated. In addition, Al ₂ (SO ₄₎ as the source of Al ions b9 and b10 in the comparative example with _3, Al quantity and Al ₂ O ₃ amount is less remarkable, it was my sulfide blackening Chengdu "Not Good".

While the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims. It is to be understood that they fall within the technical scope of the invention.

According to the embodiment described above, it is possible to provide a chemically treated steel sheet and a method for producing a chemically treated steel sheet having excellent corrosion resistance and blackening resistance to blackening, even when the amount of chemically treated coat layer is small.

10: Chemical treated steel sheet
103: steel plate
105: Ni plating layer
105d: Fe-Ni-Sn alloy layer
105e: island-shaped Sn plating layer
106: Composite plating layer
107: Chemical conversion coating layer

Claims (8)

A steel plate;
A plating layer formed on at least one surface of the steel sheet and containing Ni;
A Zr compound of 1.0 to 150 mg / m 2 in terms of a metal Zr amount, a phosphoric acid compound in a P amount of 1.0 to 100 mg / m 2, and an Al compound in an amount of 0.10 to 30.0 mg / The chemical conversion coating layer
And,
Wherein the plating layer comprises:
A Ni plating layer containing Ni in an amount of 5.0 to 3000 mg / m < 2 >
Which is a composite plating layer containing Ni of 2.0 to 200 mg / m < 2 > in terms of metal Ni and Sn in an amount of 0.10 to 10.0 g / m < 2 >
Wherein the chemical conversion treatment is carried out at a temperature of 100 ° C. The method according to claim 1, wherein the chemical conversion coating layer contains Al ₂ O ₃ in an amount of 0.10 to 30.0 mg /
Wherein the chemical conversion treatment is carried out at a temperature of 100 ° C. The method according to claim 1 or 2, wherein the chemical conversion coating layer
A Zr compound in an amount of 1.0 to 120 mg / m < 2 >
A phosphoric acid compound in an amount of 2.0 to 70.0 mg / m < 2 >
An Al compound in an amount of 0.20 to 20.0 mg / m < 2 >
Containing
Wherein the chemical conversion treatment is carried out at a temperature of 100 ° C. The nickel plating method according to any one of claims 1 to 3, wherein the Ni plating layer contains Ni of 10.0 to 2000 mg / m < 2 >
Wherein the chemical conversion treatment is carried out at a temperature of 100 ° C. The method according to any one of claims 1 to 3,
Ni in an amount of 5.0 to 100 mg / m < 2 >
A Sn of 0.30 to 7.0 g / m < 2 >
Containing
Wherein the chemical conversion treatment is carried out at a temperature of 100 ° C. The method according to any one of claims 1 to 5, wherein the surface of the chemical conversion coating layer is not coated with a film or a paint
Wherein the chemical conversion treatment is carried out at a temperature of 100 ° C. An Ni plating layer containing Ni in an amount of 5.0 to 3000 mg / m < 2 > in an amount of metal Ni, or Sn of 0.10 to 10.0 g / m < 2 & A plating step of forming a composite plating layer including an island-shaped Sn plating layer on the Fe-Ni-Sn alloy layer;
10 to 20,000 ppm of Zr ions, 10 to 20,000 ppm of F ions, 10 to 3000 ppm of phosphoric acid ions, a total of 100 to 30000 ppm of nitric acid ions and sulfate ions, and 500 to 5000 ppm of Al ions, (NH ₄ ) ₃ AlF ₆ at a current density of 1.0 to 100 A / dm ² and an electrolytic treatment time of 0.20 to 150 seconds by using a chemical treating solution whose temperature is 5 ° C or more and less than 90 ° C, , Thereby forming a chemical conversion coating layer on the Ni plating layer or the composite plating layer;
Having
Wherein said method comprises the steps of: The method according to claim 7,
200 to 17000 ppm Zr ions;
200 to 17000 ppm of F ions;
100 to 2000 ppm of phosphate ions;
A total of 1000 to 23000 ppm of nitrate ions and sulfate ions;
500 to 3000 ppm of Al ions;
Containing
Wherein said method comprises the steps of:

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