How to paint a product with gold paint at home? Do-it-yourself "gold" coloring technology. Methods for blackening copper How to give metal a copper color

Tin is a metal that is widely distributed and used in many areas of industry, but at the same time, this material is mostly hidden from human eyes. That is, most often tin is used as a solder for joining parts, for coating them and making various containers for food from it.

If tin is used as an independent metal and various objects or parts are made from it, then sooner or later you may be faced with the question of changing the color or how to add color to tin to make the product visually attractive. By itself, tin has a silvery-white color. To change its natural color, you first need to cover it with copper in a galvanic way, and only then paint it.

There is this recipe for coating tin with copper. For him, you will need 5 g of iron and copper sulfate, which must be dissolved in water (100 ml). Tin must be placed in this solution. If a product made of tin is of non-standard sizes and it is difficult to immerse it in this solution, you can wipe its surface with this solution using a swab.

After the product is covered with copper, you can start painting it. However, it is necessary to clean the product from contamination and degrease its surface.

The basic recipe for giving copper a golden to black color tint is this recipe. For it, 4 g of milk sugar or lactose and 4 g of sodium hydroxide are used, which must be dissolved in 100 ml of pure water. This solution is brought to a boil, after the solution has boiled for several minutes, it is necessary to gradually add a little concentrated solution of copper sulfate there. You only need 4 ml.

Now the solution is ready and you can place a copper-plated tin product there. Depending on how long this product will be in this solution, the final color will also depend. If the residence time in the solution is short, then you can get a yellow or green color, but if you increase the time, you can achieve a red, brown or even black color. It is important that the temperature of the solution is high, but not boiling.

Luxurious gold glitter used for interior decoration is always admired. Using gold paint in the interior, you can achieve a stunning effect, decorate the room with chic artistic painting. To do this, use special metallized paints, presented on the construction market in a large assortment of colors and shades.

Types of decorative compositions

It is possible to finish under gold wooden and metal surfaces, ceramics, glass and plastic. You can process everything - from the ceiling to the floor. Decorative acrylic paint is popular. It surpasses alkyd and oil formulations in many ways.

The composition can be used both for decoration and for restoration work on metal and wood. With its help, you can paint polyurethane and plaster moldings. Manufacturers produce a coloring composition in several forms:

• classic paint in a corked metal can - enamel;
• aerosol paint in spray cans;
• dry, in the form of a powder composition to be dissolved.

Each type of decorative acrylic paint has different characteristics, color and application features.

Acrylic based

There are a lot of manufacturers of golden paint, and any enamel is of good quality. An example is the acrylic decorative paint Metallic Accents.

The composition of the substance includes particles of mica, giving the coating a golden sheen and a magnificent shimmering effect. The manufacturer offered a varied palette of colors from light gold to dark brown paint. Enamel is suitable for any style of interior, wood furniture, walls, it is suitable for ceramic tile floors. For work use:

• roller;
• brush;
• spray gun;

Bosny "KT Gold Effect" aerosols have gained great popularity. The spray contains gold pigment KT-18. To make the substance more durable and get a rich bright color, acrylic resin was included in the spray paint. The spray fits perfectly on any type of surface, is used by designers when creating interior painting.

Main advantages:

• spray does not fade, retains color for a long time;
• the composition is resistant to weathering;
• does not contain toxic substances;
• has anti-corrosion and antioxidant properties;
• suitable for indoor and outdoor decoration;
• has an acceptable cost.

To achieve maximum effect, it is recommended to apply a primer of the same series before the spray. The manufacturer offers five popular shades of gold color: copper, dark gold, brass, golden branch and golden spark. Dark gold and brass are used indoors for walls, ceilings, floors, the rest of the aerosols are suitable for outdoor use.

By spraying an aerosol, it is easy to paint picture frames, legs of armchairs, chairs, giving them the beauty of antique gold, antique patina, get an interesting painting and return objects to their former attractiveness.

Sprays with chrome effect

Very often, when finishing surfaces under gold, the consumer wants to get a rich, shiny chrome effect. Jobi spray paint made in the Netherlands has proven itself to be excellent. With it, you can paint absolutely any surface. The composition with chromium has excellent characteristics:

• enamel in a can is easily applied in an even layer;
• it is universal - you can, metal, wood, fabric, ceramics;
• withstands temperatures up to 110°C;
• gives the surface a rich color and shine of chrome;
• has good covering ability;
• does not flow and dries quickly;
• you can get a waterproof reliable layer.

Up to three square meters of almost any surface can be painted with chrome shine with one can of spray paint - the composition is suitable for painting wallpaper or gypsum material, plastered ceiling, floor. A great option for creative design ideas. It is often used to obtain various products with a chrome shine - souvenirs, crafts, unusual gifts made by one's own hands.

Artistic acrylic paint

If you need to paint a wooden surface, you should use inexpensive OLKI art paint. The manufacturer positions the dry powder composition as natural gold leaf - and this is confirmed by consumers working with artistic wood painting. Distinctive features:

• the powder is diluted with water;
• the paint is easy to apply;
• has good hiding power;
• creates a solid stable layer on the surface;
• it is light gold and dark brown;
• dries quickly, emphasizes the texture of the surface;
• is inexpensive.

OLKI paint is also used for artistic painting of icon cases and icons. It is suitable for effectively painting the wooden frame of a picture or a mirror, restoring furniture.

What is remarkable about blacksmith paints

Since painting allows you to get interesting surfaces with different effects, it is used to decorate exteriors - gates, window bars, entrance doors and groups, bas-reliefs, fences (including for). With the help of blacksmith's gold paints, it is possible to obtain an unusual surface with brilliant chrome, artistic painting, or to artificially age the metal.

Hammer compositions are very popular, which give the metal texture the appearance of dents and relief left by a blacksmith's hammer.

The use of several blacksmith paints allows you to get a stunning brown patina effect, and there are more than fifty options for such an imitation. Even an inexpensive metal surface can be given a luxurious look and architectural appeal. In addition, forge paints significantly extend the service life of the metal, additionally protect it from moisture and corrosion.

Using acrylic dry, spray and enamel paints, you can implement very bold and interesting design ideas, get unusually beautiful unique surfaces, give the interior originality and chic. The only rule to follow is that there should not be too much gold. Only neat gold accents without frills will look appropriate and beautiful.

By learning how to do gilding at home, which is not as difficult as it might seem at first glance, you will be able to return a second life to your favorite copper and silver jewelry. Products made of gold have been very popular with both women and men for many years. To possess such products without serious expenses for their acquisition, it is enough to master the technology of gilding.

What metals can be gilded?

The most common process is silver plating, but gold plating can also be applied to the surface of other metals. So, gilding can be applied to and zinc, as well as iron and steel, etc.

There is no single answer to the question of how to gild metal at home. It all depends on what kind of metal products need to be subjected to such processing. The choice of gilding technology carried out at home is also influenced by the result to be achieved.

Various methods can be used to gild metal, the most common of which are:

• rubbing the surface of the product with a solution of gold chloride;
• gilding, performed by immersing the product in a solution with a zinc contact;
• electroplating gilding.

Each of these home gilding methods requires the use of certain chemicals, tools and equipment.

Preparation and use of chlorine gold

To cover a metal with a layer of gilding, a solution called gold chloride is often used. To prepare such a solution, gold is dissolved in aqua regia, which is a mixture of hydrochloric and nitric acids. Hydrochloric and nitric acids are taken in a ratio of 3: 1. Gold is placed in this composition, and then the liquid is evaporated. The procedure for evaporating liquid from such a solution should be done very carefully so as not to get burns of the skin and respiratory tract. The dry matter remaining after evaporation is precisely gold chloride.

Before using chlorine gold for gilding, it must be mixed with a solution of potassium cyanide and elutriated chalk, resulting in a mushy mass. Such gruel, using a brush, cover the product, after which it is kept for some time, and then thoroughly washed and polished.

For gilding steel, chloride gold is mixed with ether. The product covered with such a composition is left for some time until the ether completely evaporates, and then the treated surface is simply rubbed with a cloth to give it a golden sheen.

Using chloride gold, previously mixed with ether, various inscriptions and patterns can be applied to a metal object. In order to carry out such a procedure, a quill pen is dipped into the resulting solution and the required inscriptions and patterns are made, which, after evaporation of the ether and polishing, will sparkle with a golden sheen.

As mentioned above, gold plating is often applied to silver, for which chlorine gold can also be used. To perform chemical gilding of products from this metal, it is necessary to prepare a mixture that includes the following components:

• chloride gold - 10 grams;
• potassium cyanide - 30 grams;
• table salt - 20 grams;
• soda - 20 grams;
• water - 1.5 liters.

Chemical gilding to which silver is to be subjected can also be carried out using a mixture of:

• chloride gold - 7 grams;
• ferrous-cyanide potassium - 30 grams;
• potassium carbonate - 30 grams;
• food salt - 30 grams;
• water - 1 l.

The very procedure of deposition of a layer of gold on the metal surface using chemical solutions is performed in the following sequence.

1. The workpiece is pre-calcined.
2. The surface of the object is etched first with a solution of sulfuric acid, and then with nitric acid.
3. The pickled product is momentarily immersed in a mixture of sulfuric, nitric and hydrochloric acids.
4. After treatment in a mixture of acids, the product is rinsed with water, then immersed in mercury and finally in water, where it is kept for 30 seconds.
5. After a container with water, the product is placed in a solution for gilding, kept for the required time, then washed with water and dried in sawdust.

Application of zinc contact

To get a thicker gold layer, a zinc contact is used. This method can, for example, cover silver with a layer of gold. For gilding, a composition is prepared from such components as:

• chloride gold - 15 grams;
• carbonic salt - 65 grams;
• yellow blood salt - 65 grams;
• edible salt - 65 grams;
• water - 2 l.

Products made of copper and brass are covered with gold in a solution of the following composition:

• chloride gold - 2 grams;
• caustic potassium - 6 grams;
• potassium cyanide - 32 grams;
• phosphate-sodium salt - 10 grams;
• water - 2 l.

Objects, on the surface of which it is necessary to apply a layer of gilding, are thoroughly cleaned of dirt and grease, then they are placed in a pre-heated composition for gilding. Products already there are connected to a zinc rod, which acts as a contact.

In order for the gilding applied to the surface of products made of steel, zinc and tin to be of high quality and to have good adhesion, they must be subjected to a copper plating procedure before gilding.

Galvanic gilding method

The most durable and high-quality gilding layer makes it possible to obtain electroplated gold plating, performed in special electrolytic solutions. This technology of gilding is very similar to zinc plating, since it uses electroplating and similar electrochemical processes.

Depending on the chemical composition of the solution in which the galvanization is performed, the resulting gilding may have a reddish or light yellow tint. Basically, gilding of metal products using this technology is carried out in solutions of two types.

Electrolytes for gilding of the first type are prepared in the following sequence.

1. 60 grams of sodium phosphate are dissolved in 700 milliliters of water.
2. In 150 milliliters of water, 2.5 grams of gold chloride is diluted.
3. In another 150 milliliters of water, 1 gram of potassium cyanide and 10 grams of sodium disulphide are dissolved.
4. First, the first two solutions are carefully mixed, and then the third is added to the resulting mixture.

To gild silver or any other metal by this method, the prepared composition is brought to a temperature of 50–62 ° and a platinum anode is used to carry out the process. After the depletion of such an electrolyte for gilding, chloride gold is added to it.

Defects when using gilding electrolytes and ways to eliminate them

Brass and products from it in the air quickly fade and oxidize. To protect polished products from oxidation, brass parts are often coated with a special golden lacquer.

More simple and affordable way consists in the following: after thorough cleaning and polishing, the brass part is immersed in a 10-15% solution of some kind of alkali to remove fats from its surface.

Then the part is washed in water and dipped in a weak (2-3%) solution of sulfuric or hydrochloric acid for 1-2 seconds. Good results are obtained if brass is immersed in a solution of sodium bisulfite, then washed in water and immersed in a solution of copper acetate, heated to 36-40 ° C.

Depending on the time during which the part is in solution, brass is painted from a light golden color to the color of pure gold and even to a reddish-violet hue. The color of the color is monitored by removing the part from the solution from time to time. After painting, the part is washed with water and dried in air. The color is permanent and does not change over time.

Acetic acid copper is commercially available, but you can cook it yourself. To do this, dissolve 5 g of copper sulfate in 0.5 liters of water, then mix with a solution of lead acetate (pharmacy lead lotion or lead sugar).

The second solution is made up of 8 g of lead acetate and 0.5 l of water. When the solutions are mixed, lead sulphate precipitates, and copper acetate remains in the solution. This solution will serve as the working solution. The precipitate can be filtered off or left at the bottom of the vessel,

Coloring copper under gold

4 g of caustic soda and 4 g of milk sugar are dissolved in 100 g of water, boiled for 15 minutes, then, with constant stirring, 4 g of a solution of saturated copper sulfate are added in small doses. Well-cleaned copper products are immersed in the hot mixture. Depending on the duration of action, they acquire a different color - from gold, green to complete black.

Golden lacquer for brass (brass passivation)

When brass is passivated, a stable protective film is formed, similar to gilding. This film is not afraid of moisture, so anglers passivate brass spinners.

The cleaned, polished and degreased part is dipped for 1 s into a solution prepared from 1 part of nitric and 1 part of sulfuric acid, and immediately transferred to a strong solution of potassium dichromate (chromic acid) for 10-15 minutes. After that, the part is washed and dried.

Literature: V.G.Bastanov. 300 practical tips, 1986

Nickel plating of iron or steel products is carried out in a solution containing 5 g of nickel sulfate and 4 g of ammonium chloride in 100 ml of water, where additional pieces of metallic zinc are added. As a result of the release of nickel, a beautiful silvery film forms on the surface of the product.
*** To cover a copper or brass product with a nickel film, prepare a solution of 10 g of nickel sulfate and 25 g of ammonium chloride in 100 ml of water. This solution is brought to a boil, some iron filings are thrown into it, and then the product that is going to be nickel-plated is lowered.
*** Isolation of metallic nickel on the metal surface occurs as a result of the reduction of nickel sulfate with zinc or iron. The addition of ammonium chloride, which undergoes hydrolysis in an aqueous solution, creates a slightly acidic environment.
*** A high-quality nickel coating on an iron surface is obtained as follows: 3 g of nickel chloride and 1 g of sodium acetate are dissolved in 100 ml of water heated to 60 o C, then the solution is heated to 80 (C) and 1.5 g of sodium hypophosphite is added Then the degreased product is immersed in this solution and heated to 90 o C. If the temperature is lower, nickel plating will go too slowly, and at 95 o C the solution begins to decompose.
In this case, the reason for the release of metallic nickel is the reduction of nickel chloride with sodium hypophosphite in an alkaline environment, which is created during the hydrolysis of sodium acetate. When heated above 95 o C, sodium hypophosphite decomposes with the release of hydrogen, turning first into sodium phosphite Na 2 PHO 3 and then into orthophosphate Na 3 PO 4 .

copper plating. Copper coating of iron products can be carried out in a solution of 1-5 g of copper sulfate and 1-5 ml of concentrated sulfuric acid in 100 ml of water; the process takes only 3-5 seconds at room temperature. The treated thing is removed from the solution, washed with water and dried. When copper plating in this way, the copper salt is reduced with iron.
*** A denser copper film is formed if the product is first treated with a brush with a solution of 10 g of zinc chloride and 20 ml of concentrated hydrochloric acid in 20 ml of water, and then a solution of copper ammonia reagent is applied with a brush. A copper ammonia reagent is prepared by dissolving 5 g of copper sulfate in 80 ml of water and adding ammonia until a clear dark blue solution is formed. Copper-ammonia reagent is a solution of an ammonia complex of copper of composition SO 4 . The separation of a thin copper film is associated with the interaction of the surface layer of iron with the copper-ammonia complex, and pretreatment with a mixture of HCl and ZnCl 2 makes iron more chemically active.
*** For lead copper plating, a solution of 16 g of copper acetate and 15 ml of glacial acetic acid in 80 ml of water is used.

Chrome plating. Coating of steel, copper and brass products with a thin layer of chromium is carried out in a solution containing in 200 ml of water 3 g of chromium fluoride, 1.5 g of sodium hypophosphite, 1.5 g of sodium citrate, 2 ml of glacial acetic acid and 2 ml of 20% - th sodium hydroxide solution. In order for the chromium film on the surface of the product to be sufficiently thick, strong and even, the process is carried out at 80 o C for 3-8 hours, and then the product is washed with water and dried. Before chromium plating, steel objects are additionally coated with a copper film to ensure better adhesion of the applied chromium film to the surface. Chrome plating of metals by the method described here is based on chemical reactions in which sodium hypophosphite and sodium citrate serve as metal reducing agents.

Tinning.(plating with a layer of tin) iron or steel products are carried out at room temperature in a solution containing 2 g of tin chloride SnCl 2 and 10 g of sodium lactate in 100 ml of water.
*** For tinning copper, bronze or brass products, prepare a solution of 1 g of tin chloride and 30 g of ammonium alum in 100 ml of water.
*** Zinc objects are covered with a layer of tin in a solution that contains 20 g of tin chloride and 40 g of potassium hydrotartrate (tartar) in 100 ml of water. A film of tin on zinc forms as a gray coating after just a few seconds. The product is removed from the solution and wiped with a cloth until it shines.

Silvering any fat-free metals are carried out in a boiling solution containing 12 g of yellow blood salt, 8 g of potash and 0.75 g of silver chloride in 100 ml of water. When heated, the sparingly soluble silver chloride is converted into a complex compound of composition K, which is then reduced on the iron surface to metallic silver. At the same time, potassium carbonate removes excess iron salts from the solution, which prevents the formation of a strong silver film, and precipitates a brown precipitate of iron hydroxide.
*** You can also silver metal products with a liquid paste consisting of 10 g of silver chloride, 60 g of table salt, 60 g of cream of tartar and 50 ml of water. Grind in a mortar a mixture of the specified composition, and then, immersing the product in the resulting slurry, heat it for 15--20 minutes. The silver coating obtained by this method is beautiful, but lacks luster. To make it shine like a mirror, the paste is washed off the product, immersed in a solution of 6 g of sodium hyposulfite and 2 g of lead acetate in 100 ml of water and heated to 70-80 o C for 1-15 minutes.
*** Photo paper can also be used for silvering. It is cut into pieces and dipped in a solution of sodium hyposulfite. A fat-free product is also placed in this solution and, wearing rubber gloves, rub its surface with an emulsion layer of photographic paper until a sufficiently dense layer of silver is formed. After washing, the product can only be wiped with a dry cloth.

Turning brass into "gold". If a brass product, after cleaning and degreasing, is immersed in an aqueous solution of copper acetate heated to 30--40 o C, then, depending on the duration of processing, it will take on a new color - from light yellow to ruby ​​red and even purple. Then the product is washed with water and dried. The concentration of copper acetate is selected empirically.
Brass is an alloy of copper and zinc. The appearance of color during the chemical treatment of its surface is due to the reaction of zinc reduction of the dissolved copper salt. Copper, standing out on the surface of brass, gives it different (depending on the thickness of the layer) shades of red. To make the copper coating more durable, it is coated with a colorless varnish.

Turn tin into "bronze" you can, if you immerse it in a solution of 5 g of copper sulfate and 5 g of iron sulfate in 100 ml of water. You can simply wipe the surface of the product with a swab moistened with the same solution. After processing, the product is washed with water, dried, wiped with a cloth and immersed in a solution of 25 g of copper acetate in 100 ml of 10% acetic acid.

bluing- This is the coloring of iron or steel objects in blue-black.
*** This process is carried out by immersing steel or iron objects in a solution heated almost to boiling, containing 7 g of sodium hyposulfite and 2 g of lead acetate in 100 ml of water, and keep it there until the surface of the metal turns black and blue. . When bluing, a thin film of lead sulfide is formed on the product, firmly bonded to the metal.
*** The dark blue color of an iron or steel product is given by keeping in a mixture of equal volumes of 0.5% solutions of red blood salt and iron (II) chloride. The mixture is prepared immediately before metal processing, since the reaction of the formation of a blue complex compound - turnbull blue (iron-potassium hexacyanoferrate) immediately occurs.
*** Brass can also be painted in the color of "crow's wing" if the brass part is lowered for 1--3 minutes into a solution of the copper ammonia complex, obtained by dissolving 12 g of the basic salt of the Cu 2 CO 3 (OH) 2 composition in 100 ml of 25% th ammonia solution and add 0.1 g of brass filings.

Brass will turn brown, if processed:
*** heated to 70 o With an aqueous solution of 10 g of sodium sulfide in 100 ml of water;
*** heated to 70 o With an aqueous solution of 5 g of sodium hyposulfite and 5 g of copper sulfate in 100 ml of water;
*** heated to 80--90 o With a mixture of equal volumes of 6% lead acetate solution and 18% sodium hyposulfite solution.

For "coloring" copper products in various colors We recommend using the following recipes:
*** 4 g of sodium hydroxide and 4 g of lactose (milk sugar) are dissolved in 100 ml of water, the solution is boiled for several minutes, and then 4 ml of a concentrated solution of copper sulphate is added in small portions with continuous stirring. The defatted product is immersed in a hot solution, and depending on the duration of treatment, its surface acquires a color from golden to green, brown or even black.
As a result of the redox chemical reaction of copper sulfate with lactose in an alkaline medium, gluconic acid is obtained and a precipitate of copper (I) oxide is released. First, a thin yellow Cu 2 O film is formed, which gives the copper surface a golden hue. With prolonged heating, the Cu 2 O crystals become coarser and turn dark red, hence the change in the color of the coating.
*** prepare a solution of 2 g of nickel sulfate, 4 g of Bertolet salt, 18 g of copper sulfate and 0.2 g of potassium permanganate in 100 ml of water. Processing copper products with a warm solution of this composition gives them a "bronze" look;
*** Dissolve 12.5 g of ammonium carbonate in 100 ml of water and add 4 ml of ammonia. The resulting solution is applied with a brush to the surface of the product and a greenish surface is obtained. Under the action of ammonia on the copper surface in the presence of atmospheric oxygen, a complex salt is formed, which then interacts with ammonium carbonate, releasing a green precipitate of copper hydroxide carbonate Сu 2 CO 3 (OH) 2 on the metal surface.

Aluminum "pearl". Clean the aluminum surface with a metal brush, applying strokes in different directions. Chips and dirt are removed with a clean rag and on the prepared surface heated to 80 o C, a 10% solution of sodium hydroxide heated to 90 o C is applied with a brush in an even layer. After the solution dries, a beautiful film similar to mother-of-pearl forms on the metal surface. For better preservation, it is covered with a colorless varnish.