JPS6230263B2 - - Google Patents
Info
- Publication number
- JPS6230263B2 JPS6230263B2 JP3434284A JP3434284A JPS6230263B2 JP S6230263 B2 JPS6230263 B2 JP S6230263B2 JP 3434284 A JP3434284 A JP 3434284A JP 3434284 A JP3434284 A JP 3434284A JP S6230263 B2 JPS6230263 B2 JP S6230263B2
- Authority
- JP
- Japan
- Prior art keywords
- plating layer
- treatment
- alloyed
- treated
- nitric acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/48—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 not containing phosphates, hexavalent chromium compounds, fluorides or complex fluorides, molybdates, tungstates, vanadates or oxalates
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
Description
（産業上の利用分野）
本発明は、事務用品、光学機器、自動車部品等
の分野で、最近、裸使用の用途を開拓しつつある
黒色化鋼板とその製法に関する。
（従来技術とその問題点）
従来のメツキ鋼板は、外観が白色、あるいは灰
白色であり、高級感に欠けるので、裸使用を目的
とした用途にはあまり適さない。
そこで最近、表面を黒色化した鋼板が開発さ
れ、裸使用でも外観的に十分高級感を有するた
め、事務用品、カメラ等の光学機器、オーデイオ
等の電気製品、自動車部品等の広い分野で使用さ
れてきた。即ち、公知の鋼板黒色化法としては、
下記のような方法があげられる。
(イ) カーボンブラツク等を主成分とした黒色樹脂
皮膜を、鋼板もしくはメツキ鋼板表面に形成す
る方法（特開昭58−62996）。
(ロ) 鋼板表面にAgを含む皮膜を形成する方法。
(ハ) 鋼板を、タンニン鉄水溶液に無機物の硝酸塩
を添加した処理液で処理する方法（特開昭56−
62968）。
(ニ) Co及び添加剤を含むZnメツキ鋼板を陽極処
理する方法（特開昭58−151490、特開昭58−
151491）。
しかし、これら公知の方法には、(1)銀等の貫金
属を使用するので、コスト的に不利である、(2)カ
ーボンブラツク等を主成分とする皮膜は密着性が
劣る、(3)処理方法及び設備が複雑である、等の問
題点がある。
本発明者は、上述のような問題点を改善する目
的で、先に、特願昭58−228471号を提案した。こ
の特願昭58−228471号の発明は、鋼板表面に施し
たNiメツキ層又は合金化Niメツキ層を、硝酸、
硝酸を主成分とする混酸等の黒色化処理液で処理
するもので、処理工程が極めて簡単でしかも安価
である等のメリツトはあるが、得られた鋼板の色
調が干渉色を有する黒色を呈し易く、その処理条
件も微妙で処理範囲が狭い等の点で、未だ十分と
は言えなかつた。
（発明の目的）
本発明は、上述のような問題点を改善したもの
で、特に特願昭58−228471号の発明を更に改善し
た黒色化鋼板とその製法を提供するものである。
（発明の構成と作用）
本発明の骨子は、鋼板表面に施したNiメツキ
層、合金化Niメツキ層又は合金化Coメツキ層
を、硝酸、硝酸を主成分とする混酸等の処理液で
一次処理した後、これを水洗することなしに、直
ちに、水酸化ナトリウム、水酸化カリウム、水酸
化カルシウム等のアルカリ水溶液により二次処理
して、黒色化層を表面に形成する方法とそれによ
り得られた鋼板にある。先ず、本発明の方法につ
いて説明すれば、第２図に示すように、最上層に
Niメツキ層、合金化Niメツキ層又は合金化Coメ
ツキ層等(2)を施した鋼板１は、黒色化一次処理工
程３で、硝酸等の処理液で処理され、表面に黒色
化皮膜を形成する。但し、ここで形成された黒色
化皮膜は、その処理液の濃度または処理時間によ
り外観が変化したり、あるいは干渉色が非常に多
いものとなり易い。そこで、一次処理工程３に引
き続き、これを水洗することなしに、水酸化ナト
リウム等のアルカリ水溶液で二次処理４すると、
処理液の濃度及び処理時間にあまり左右されず、
また黒色のみで干渉色を全く含まない美しい黒色
化皮膜７が得られる。ただし、工程４を行つた後
は、反応を停止させるため水洗５を行ない、これ
を乾燥６させる。
本発明で黒色化処理を施される処理材は、Ni
メツキ鋼板、Zn―Niメツキのような合金化Niメ
ツキ鋼板、あるいは、最上層にNiメツキ層、Zn
―Niメツキ層のような合金化Niメツキ層を有す
る複合メツキ鋼板又は、合金化Coメツキ層を有
する複合メツキ鋼板である。複合メツキ鋼板とし
ては、最上層（第１層）が上述のようなメツキ層
であれば、第２層以下はどのようなメツキでも良
い。合金化Niメツキ層中には、Niが１％以上含
まれていれば良い。
合金化Coメツキ層としては、Zn―Co―Cr又は
Zn―Ni―Co等があり、Co含量としては１〜10％
含まれる。Niが１％以下では処理後も黒色化が
不十分であり、Coが１％以下でも同様である。
但し、NiとCoの両方を含む場合は、両者を合わ
せた量が全体の１％以上であれば良い。
一次処理液としては、硝酸、硝酸を主成分とす
る混酸、或は混酸に添加剤として硫酸塩（硫酸ア
ンモン、硫酸ナトリウム、硫酸ニツケル等）又は
硝酸塩（硝酸ニツケル等）を加えたもの、または
次亜塩素酸等の酸化剤を主成分とする溶液等を用
いる。硝酸を用いる場合には、濃度は30％以下に
する。下限は特にないが、反応時間等から考え
て、実際的には１％以上が好ましい。30％以上で
は処理速度が早すぎるため、処理の制御ができな
い。好ましい範囲は、２〜15％である。処理時間
は、液組成、温度などにより影響を受けるが、常
温（約20℃）では、１〜30秒で良い。表面の黒色
化はNiの酸化物又は、Coの酸化物（Co3 O4）によ
るものと考えられる。
ただし、この一次処理だけでは、例えば、３％
の硝酸で20℃で２秒処理した場合は青色となり黒
色とはならない。そこで一次処理の後、水洗する
ことなしに、NaOH、KOH、Ca（OH）2等のアル
カリ水溶液で二次処理する。水洗してからアルカ
リで処理しても黒色化は進まない。アルカリ水溶
液の濃度は、特に限定されないが、１〜30％程度
が好ましい。アルカリ水溶液による二次処理は１
秒程度で十分であるが、それ以上であつても問題
はない。硝酸等による一次処理及びNaOH等によ
る二次処理の処理方法としては、浸漬、スプレー
処理などが考えられるが、処理液が処理材に接触
すれば、どの様な方法でも良い。黒色化処理後
は、濡れた状態で長時間放置すると白錆が発生す
ることがあるが、水洗後できるだけ速く乾燥す
る。
処理時間は処理液及びメツキの目付量によつて
異なるが一次処理をあまり長時間行なうと、下地
の鉄が露出して好ましくない。
次に、本発明を実施例により説明する。
実施例 １
Ni15％、Zn85％、メツキ付着量20g／m2のZn―
Ni合金化電気メツキ鋼板を、常温で、５秒間、
表に示す処理液で、それぞれ一次処理した後、５
％NaOH（40℃）で５秒間二次処理した。
(Field of Industrial Application) The present invention relates to a blackened steel sheet and a method for producing the same, which have recently been developed for use in the field of office supplies, optical equipment, automobile parts, and the like. (Prior art and its problems) Conventional plated steel sheets have a white or gray-white appearance and lack a sense of luxury, so they are not very suitable for applications intended for naked use. Recently, a steel plate with a blackened surface has been developed, and because it has a sufficiently luxurious appearance even when used bare, it is used in a wide range of fields such as office supplies, optical equipment such as cameras, electrical products such as audio equipment, and automobile parts. It's here. That is, the known steel plate blackening method is as follows:
The following methods are available. (a) A method of forming a black resin film mainly composed of carbon black or the like on the surface of a steel plate or a galvanized steel plate (Japanese Unexamined Patent Publication No. 1983-62996). (b) A method of forming a film containing Ag on the surface of a steel plate. (c) A method of treating a steel plate with a treatment solution containing an aqueous solution of iron tannin and an inorganic nitrate (Japanese Unexamined Patent Application Publication No. 1983-1999)
62968). (d) Method of anodizing a Zn-plated steel sheet containing Co and additives (Japanese Patent Application Laid-Open No. 151490, 1983)
151491). However, these known methods (1) are disadvantageous in terms of cost because they use metals such as silver, (2) coatings whose main component is carbon black etc. have poor adhesion; (3) There are problems such as complicated processing methods and equipment. The present inventor previously proposed Japanese Patent Application No. 58-228471 for the purpose of improving the above-mentioned problems. The invention of Japanese Patent Application No. 58-228471 discloses that the Ni plating layer or alloyed Ni plating layer applied to the surface of the steel sheet is treated with nitric acid.
It is treated with a blackening treatment solution such as a mixed acid containing nitric acid as the main component, and has the advantages of being extremely simple and inexpensive, but the resulting steel sheet has a black color tone with interference color. However, the processing conditions are delicate and the processing range is narrow, so it is still not sufficient. (Purpose of the Invention) The present invention is to improve the above-mentioned problems, and particularly to provide a blackened steel sheet and a method for manufacturing the same which further improves the invention of Japanese Patent Application No. 58-228471. (Structure and operation of the invention) The gist of the present invention is to first treat a Ni plating layer, an alloyed Ni plating layer, or an alloyed Co plating layer applied to the surface of a steel plate with a treatment liquid such as nitric acid or a mixed acid mainly composed of nitric acid. A method of forming a blackened layer on the surface by immediately performing a secondary treatment with an alkaline aqueous solution such as sodium hydroxide, potassium hydroxide, calcium hydroxide, etc. without washing with water after the treatment; It is on a steel plate. First, to explain the method of the present invention, as shown in FIG.
The steel plate 1 coated with a Ni plating layer, an alloyed Ni plating layer, an alloyed Co plating layer, etc. (2) is treated with a treatment liquid such as nitric acid in the blackening primary treatment step 3 to form a blackening film on the surface. do. However, the blackened film formed here tends to change in appearance depending on the concentration of the processing liquid or the processing time, or to have a large number of interference colors. Therefore, following the primary treatment step 3, without washing with water, a secondary treatment 4 is performed with an alkaline aqueous solution such as sodium hydroxide.
It is not affected much by the concentration of the processing solution or the processing time.
Moreover, a beautiful blackened film 7 that is only black and does not contain any interference color can be obtained. However, after performing step 4, washing with water 5 is performed in order to stop the reaction, and this is dried 6. The treated material subjected to the blackening treatment in the present invention is Ni
Plated steel plate, alloyed Ni plated steel plate such as Zn-Ni plated, or Ni plated layer on the top layer, Zn
- A composite plated steel sheet having an alloyed Ni plating layer such as a Ni plating layer, or a composite plated steel sheet having an alloyed Co plating layer. As for the composite plated steel sheet, as long as the uppermost layer (first layer) is the above-mentioned plating layer, the second and subsequent layers may have any plating. It is sufficient that the alloyed Ni plating layer contains 1% or more of Ni. As the alloyed Co plating layer, Zn-Co-Cr or
There are Zn-Ni-Co, etc., and the Co content is 1 to 10%.
included. When Ni is 1% or less, blackening is insufficient even after treatment, and the same is true when Co is 1% or less.
However, if both Ni and Co are included, the combined amount of both should be 1% or more of the total. The primary treatment liquid may be nitric acid, a mixed acid containing nitric acid as its main component, a mixed acid with sulfate (ammonium sulfate, sodium sulfate, nickel sulfate, etc.) or nitrate (nickel nitrate, etc.) added as an additive, or the following: Use a solution whose main component is an oxidizing agent such as chlorous acid. When using nitric acid, the concentration should be 30% or less. Although there is no particular lower limit, in consideration of reaction time, etc., 1% or more is actually preferable. If it is 30% or more, the processing speed is too fast and the processing cannot be controlled. The preferred range is 2-15%. The processing time is affected by the liquid composition, temperature, etc., but at room temperature (approximately 20°C), it may be 1 to 30 seconds. The blackening of the surface is thought to be due to Ni oxide or Co oxide (Co 3 O 4 ). However, with this primary treatment alone, for example, 3%
When treated with nitric acid at 20°C for 2 seconds, the color becomes blue and not black. Therefore, after the primary treatment, a secondary treatment is performed with an alkaline aqueous solution such as NaOH, KOH, Ca(OH) 2 , etc. without washing with water. Even if it is washed with water and then treated with alkali, the blackening will not progress. The concentration of the alkaline aqueous solution is not particularly limited, but is preferably about 1 to 30%. Secondary treatment with alkaline aqueous solution is 1
A time of about seconds is sufficient, but there is no problem even if it is longer. Possible treatment methods for the primary treatment with nitric acid or the like and the secondary treatment with NaOH or the like include immersion and spray treatment, but any method may be used as long as the treatment liquid comes into contact with the treated material. After blackening treatment, white rust may occur if left wet for a long time, but dry as quickly as possible after washing with water. The treatment time varies depending on the treatment solution and the basis weight of the plating, but if the primary treatment is carried out for too long, the underlying iron will be exposed, which is undesirable. Next, the present invention will be explained by examples. Example 1 Zn--15% Ni, 85% Zn, plating amount 20g/ m2
Ni-alloyed electroplated steel sheet at room temperature for 5 seconds.
After primary treatment with the treatment liquid shown in the table,
% NaOH (40°C) for 5 seconds.
【表】
○ 良好
× 黒色化ナシ
HNO3は優れた黒色化処理液であるが、その他
の酸では黒色化は行われなかつた。
実施例 ２
Ni10％、Zn90％、メツキ付着量30g／m2のZn―
Ni合金化電気メツキ鋼板を、常温で硝酸により
一次処理した後、20％NaOH（20℃）で２秒間二
次処理した。一次処理の硝酸濃度と処理時間を変
化させて黒色化試験を行つた。試験結果を第１図
に示す。
１図―ａは一次処理のみであり、１図―ｂは一
次処理の後、二次処理を行なつた結果である。第
１図において、○印は黒色化良好な条件を、×印
は黒色化不良の条件を示す。
実施例 ３
Ni10％、Co2％、Co88％、メツキ付着量20g／
m2のNi―Zn合金化電気メツキ鋼板を、３％HNO3
（25℃）で一次処理後、10％NaOH（50℃）で５
秒間二次処理した。一次処理時間を１〜20秒の範
囲で変化させて試験した。一方、比較例として、
二次処理を施さない一次処理のみの黒色化試験を
行つた
本発明の方法によれば、干渉色を全く有しない
黒色が、一次処理時間１秒〜20秒の範囲にわたつ
て得られたが、比較例では、７秒以内では青色を
呈し、７秒〜20秒の範囲では、干渉色を有し、処
理時間により色調の異なる黒色となつた。
（発明の効果）
本発明の黒色化鋼板は、従来の黒色化鋼板に比
較して、Ag等の貫金属を用いないでコスト的に
有利であり、メツキ層を黒色化するので密着性も
良好で、さらに、干渉色を全く有しない黒色化鋼
板で、しかも非常に緻密な表面を有するので、高
級感があり裸使用が十分可能である等の点で優れ
ている許りでなく、その製法も簡単で、設備にも
複雑なものを要せず、処理条件も非常に広い等、
極めて有効な発明である。[Table] ○ Good × No blackening
HNO 3 is an excellent blackening solution, but other acids did not produce blackening. Example 2 Zn--10% Ni, 90% Zn, plating amount 30g/ m2
A Ni-alloyed electroplated steel sheet was first treated with nitric acid at room temperature, and then secondly treated with 20% NaOH (20°C) for 2 seconds. A blackening test was conducted by varying the nitric acid concentration and treatment time in the primary treatment. The test results are shown in Figure 1. Figure 1-a shows only the primary processing, and Figure 1-b shows the result of performing the secondary processing after the primary processing. In FIG. 1, ◯ marks indicate conditions with good blackening, and × marks indicate conditions with poor blackening. Example 3 Ni10%, Co2%, Co88%, plating amount 20g/
m 2 of Ni-Zn alloyed electroplated steel plate with 3% HNO 3
After primary treatment at (25℃), 5% NaOH (50℃)
Secondary processing was performed for seconds. The primary treatment time was varied in the range of 1 to 20 seconds. On the other hand, as a comparative example,
According to the method of the present invention, which conducted a blackening test using only the primary treatment without secondary treatment, a black color with no interference color was obtained over a primary treatment time range of 1 second to 20 seconds. In the comparative example, it exhibited a blue color within 7 seconds, had an interference color in the range of 7 seconds to 20 seconds, and became black with a different tone depending on the processing time. (Effects of the invention) Compared to conventional blackened steel sheets, the blackened steel sheet of the present invention is advantageous in terms of cost because it does not use penetrating metals such as Ag, and has good adhesion because the plating layer is blackened. Furthermore, since it is a blackened steel sheet that has no interference color at all and has a very fine surface, it is not only superior in that it has a luxurious feel and can be used naked, but also because of its manufacturing method. It is simple, does not require complicated equipment, and has a wide range of processing conditions.
This is an extremely effective invention.
第１図は、実施例２の試験結果を示す図、第２
図は、本発明の製法を示す説明図である。
１…鋼板、２…Niメツキ層等、３…一次処理
工程、４…二次処理工程、５…水洗工程、６…乾
燥工程、７…黒色化皮膜。
Figure 1 is a diagram showing the test results of Example 2;
The figure is an explanatory diagram showing the manufacturing method of the present invention. 1... Steel plate, 2... Ni plating layer, etc., 3... Primary treatment process, 4... Secondary treatment process, 5... Water washing process, 6... Drying process, 7... Blackening film.
Claims (1)
Coメツキ層を、硝酸、硝酸を主成分とする混酸
等の処理液による一次処理と、NaOH、KOH、
Ca（OH）2等のアルカリ水溶液による二次処理し
て得た黒色化層を、最上層として有することを特
徴とする黒色化鋼板。 ２ 最上層として、Niメツキ層、合金化Niメツ
キ層、又は合金化Coメツキ層を有するメツキ鋼
板を、先ず、硝酸、硝酸を主成分とする混酸、或
は混酸に添加剤として硫酸塩又は硝酸塩を加えた
もの、又は次亜塩素酸等の酸化剤を主成分とする
溶液等の処理液で一次処理した後、これを水洗す
ることなく、NaOH、KOH、Ca（OH）2等のアル
カリ水溶液で二次処理することを特徴とする黒色
化鋼板の製法。[Claims] 1 Ni plating layer, alloyed Ni plating layer or alloying
The Co plating layer is first treated with a treatment solution such as nitric acid or a mixed acid mainly composed of nitric acid, and then treated with NaOH, KOH,
A blackened steel sheet characterized by having a blackened layer obtained by secondary treatment with an aqueous alkali solution such as Ca(OH) 2 as the uppermost layer. 2. A plated steel sheet having a Ni plating layer, an alloyed Ni plating layer, or an alloyed Co plating layer as the top layer is first treated with nitric acid, a mixed acid mainly composed of nitric acid, or a mixed acid with sulfate or nitrate as an additive. After primary treatment with a treatment solution such as a solution containing oxidizing agents such as hypochlorous acid or a solution containing oxidizing agents such as hypochlorous acid as a main component, it can be treated with an alkaline aqueous solution such as NaOH, KOH, Ca(OH) 2 , etc. without washing with water. A method for producing blackened steel sheets characterized by secondary treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3434284A JPS60181277A (en) | 1984-02-27 | 1984-02-27 | Blackened steel sheet and its production |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3434284A JPS60181277A (en) | 1984-02-27 | 1984-02-27 | Blackened steel sheet and its production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60181277A JPS60181277A (en) | 1985-09-14 |
| JPS6230263B2 true JPS6230263B2 (en) | 1987-07-01 |
Family
ID=12411458
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3434284A Granted JPS60181277A (en) | 1984-02-27 | 1984-02-27 | Blackened steel sheet and its production |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60181277A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ATE530680T1 (en) * | 2009-03-20 | 2011-11-15 | Universo Sa | GALVANIC COATING PROCESS FOR APPLYING AN ANTHRACITE-COLORED COATING AND METAL PARTS PROVIDED WITH THIS COATING |
-
1984
- 1984-02-27 JP JP3434284A patent/JPS60181277A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60181277A (en) | 1985-09-14 |
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