KR102336506B1 - A Cyanide Copper Plating Solution And A Method for Cyanide Copper Plating Using The Same - Google Patents

Abstract

An embodiment of the present invention provides a copper cyanide plating solution comprising a 3-hexaine-2,5-diol compound and a sulfur compound. In addition, there is provided a copper cyanide plating method using the copper cyanide plating solution.

Description

A Cyanide Copper Plating Solution And A Method for Cyanide Copper Plating Using The Same}

The present invention relates to a copper cyanide plating solution, and more particularly, to a copper cyanide plating solution including a semi-glossy additive for improving adhesion of the surface of the copper cyanide plating solution and a copper cyanide plating method using the same.

As the overall market size of telecommunication, home appliances, machinery and automobile industries expands, the proportion of metal surface treatment technology is increasing. have.

In order to implement such a high corrosion-resistance metal surface treatment, a multi-layer plating technology in the form of "material-plating layer-plating layer-plating layer" is essential, rather than one-dimensional plating that simply deposits a single metal plating layer thickly on the material. In order to implement such multi-layer plating, strong adhesion between the material-plating layer and the plating layer-plating layer is required.

On the other hand, copper (Copper) is easily discolored in the air, but has excellent thermal and electrical conductivity and excellent workability, so it is widely used as pre-plating in various types of plating to improve adhesion. Copper strike plating, which has good adhesion and covering power, is mainly used for copper base plating.

Plating solutions used for copper plating include copper cyanide plating, copper sulfate plating, and copper pyrophosphate plating, but copper cyanide plating can directly plated on steel and has good adhesion, so it is used for copper strike plating.

In general, in copper cyanide plating, a brightener is added to the plating solution to realize stronger adhesion through the modification of the precipitation structure. The brightener plays a role in improving the adhesion and glossiness of the post-plating by improving the original adhesion of the copper-clad plating and controlling the glossiness of the copper plating layer.

If the glossiness of the copper plating layer is too low, the adhesion with the post plating layer is increased, but the glossiness of the post plating layer is deteriorated. Conversely, when the glossiness of the copper plating layer is too high, a film of the organic raw material of the brightener is formed on the surface of the deposited copper plating layer, thereby reducing adhesion with the post plating layer, and the post plating layer may be easily separated. Therefore, it is important to uniformly maintain the glossiness of the copper plating layer within a certain range, and for this purpose, it is necessary to control the type and content of the polishing agent.

On the other hand, in general, heavy metal components such as lead (Lead, Pb) or cadmium (Cd) were mainly used as the components of brightening agents, but in the early 2000s, RoHS (Restriction of Hazardous) regulating the use of heavy metals in the European Union (EU) Substances, Cd, Pb, Hg, Cr6+, PBB, PBDE use control bill), the use of heavy metals such as lead and cadmium is currently fully regulated, and other environmental regulations such as SVHC (Substances of Very High Concern) Therefore, the range of materials that can be used as raw materials for brightening agents is quite limited.

In addition, in general, varnishes distributed and used in the market are multi-component varnishes of 2 to 3 components. During continuous operation, 2 or more varnishes must be continuously replenished, and the use temperature needs to be maintained at a high ^{temperature of 65 o C or higher.} , there is a problem that a glossy mirror surface is formed on the surface of the precipitation, and the surface tension of the surface is increased. High surface tension lowers adhesion with the post-plating layer and causes unevenness on the surface of the post-plating layer. In addition, there is a problem that the glossy surface tends to be biased in the high current portion according to the difference in current density, resulting in gloss deviation from the low current portion.

Therefore, it is necessary to introduce a copper cyanide plating solution and plating method that can cope with these domestic and foreign environmental regulations, improves the original function of copper cyanide plating, is easy to use and manage in the plating process, and does not contain heavy metals and metal salts. have.

In order to solve the problems of the prior art, an object of the present invention is to provide a copper cyanide plating solution and a copper cyanide plating method including a semi-glossy additive that does not contain heavy metals.

In addition, an object of the present invention is to provide a copper cyanide plating solution and a copper cyanide plating method for forming a copper plating layer having excellent adhesion and adequate gloss.

In addition, an object of the present invention is to provide an efficient and economical copper cyanide plating method that is easy to use and manage in a plating process, and is effective in a mild condition.

In addition to the aspects of the present invention mentioned above, other features and advantages of the present invention will be described below or will be clearly understood by those of ordinary skill in the art from such description.

In order to solve this problem, an embodiment of the present invention is a copper cheonghwa compound; and a semi-gloss additive, wherein the semi-gloss additive includes: a 3-hexain-2,5-diol (3-Hexyne-2,5-diol) compound; and a sulfur compound; provides a copper cyanide plating solution comprising.

The copper cyanide compound may include copper cyanide (CuCN), sodium cyanide (Na ₂ Cu(CN) ₃ ), potassium cyanide (K ₂ Cu(CN) ₃ ), or a mixture thereof.

The copper cyanide compound is copper cyanide (CuCN); and at least one of sodium cyanide (NaCN) and potassium cyanide (KCN).

The copper cyanide (CuCN) may be 10 to 50 g/L compared to the copper cyanide plating solution, and at least one of sodium cyanide (NaCN) and potassium cyanide (KCN) may be 25 to 65 g/L compared to the copper cyanide plating solution.

The 3-hexaine-2,5-diol compound may be in an amount of 0.5 to 10 g/L compared to the copper cyanide plating solution.

The sulfur compound may include at least one of sodium saccharin, sodium vinyl sulfonate, and sodium allyl sulfonate.

The sulfur compound may be 0.75 to 4.00 g/L compared to the copper cyanide plating solution.

The semi-glossy additive may further include N-polyether (N-Polyether) and L-polyether (L-Polyether).

The N-polyether (N-Polyether) may be 0.015 to 0.45 g/L compared to the copper cyanide plating solution, and the L-polyether (L-Polyether) may be 0.015 to 0.45 g/L compared to the copper cyanide plating solution.

The semi-gloss additive may further include at least one of butynediol ethoxylate, 2-butyne-1,4-diol, and glycine.

At least one of butynediol ethoxylate and 2-butyne-1,4-diol is 0.075 to 0.375 g/L compared to the copper cyanide plating solution, and the glycine is 0.075 g/L compared to the copper cyanide plating solution L to 0.525 g/L.

The semi-glossy additive may further include a surfactant, and the surfactant may include a fluorinated surfactant.

The fluorine-based surfactant may include a potassium perfluorobutane sulfonate compound.

The fluorine-based surfactant may be 0.05 to 0.15 g/L compared to the copper cyanide plating solution.

The copper cyanide plating solution may further include at least one or more of an organic acid salt and an inorganic acid salt.

The organic acid salt may include at least one of potassium sodium tartrate, sodium carbonate, and potassium carbonate.

The inorganic acid salt may include at least one of sodium hydroxide and potassium hydroxide.

According to another aspect of the present invention, the preparation step of the subject to be plated; Preparation of copper cheonghwa plating solution; and plating a copper cyanide plating solution on the surface of the substrate to be plated through electroplating using the copper cyanide plating solution, wherein the copper cyanide plating solution is a cyanide copper plating solution of the present invention.

The copper plating step includes a temperature of ^{30 to 50 o C;} and a current density of 1 to 10 A/dm ² ; it may be performed.

According to one embodiment of the present invention, it is possible to form a copper plating layer having excellent adhesion and appropriate gloss without using a brightener containing a heavy metal.

In addition, according to an embodiment of the present invention, it is possible to provide a copper cyanide plating solution containing a one-component semi-glossy additive that is easy to use and manage.

In addition, according to another embodiment of the present invention, it is possible to perform a plating process at a relatively low temperature and at a high speed, thereby increasing fixing efficiency and providing an economically advantageous copper cyanide plating method.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are intended to aid the understanding of the present invention and constitute a part of this specification, illustrate embodiments of the invention, and together with the description, explain the principles of the invention.
1 is a schematic cross-sectional view of a multilayer plating 10 according to an embodiment of the present invention.
2 is a flowchart of a copper bronze plating method using the copper cyanide plating solution of the present invention.
Figure 3 is a photograph of the implementation of the Hull Cell Test (Hull Cell Test) to test the performance of the copper cyanide plating solution.
4 is a photograph of the surface of the plated specimen after conducting the Hullcell test using the copper cyanide plating solution of Comparative Examples 1 to 5 of the present invention.
5 is a photograph showing the surface of the plated specimen after carrying out the Hullcell test using the copper cyanide plating solution of Example 1 and Comparative Example 5 of the present invention.
6 is a photograph showing the surface of the plated specimen after carrying out the Hullcell test using the copper cyanide plating solution of Examples 2 to 9 of the present invention.
7 is a photograph showing the surface of the plated specimen after carrying out the Hullcell test using the copper cyanide plating solution of Example 9 and Comparative Example 6 of the present invention.
8 is a photograph of the surface of the specimen plated using Examples 9 to 11 of the present invention at a magnification of 550 using an electron microscope.
9 is a photograph of the outer shape of the specimen plated using Examples 9 and 11 and Comparative Example 6 of the present invention.
10 is a photograph of the outer appearance of the nickel-plated specimen after the copper cyanide plating of Example 11 and Comparative Examples 1 and 6 of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

It will be apparent to those skilled in the art that various changes and modifications of the present invention are possible without departing from the spirit and scope of the present invention. Accordingly, the present invention includes all modifications and variations within the scope of the invention as set forth in the claims and their equivalents.

Since the shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are exemplary, the present invention is not limited by the matters shown in the drawings. Throughout the specification, like elements may be referred to by like reference numerals.

When 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless the expression 'only' is used. When a component is expressed in the singular, the plural is included unless specifically stated otherwise. In addition, in interpreting the components, it is interpreted as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, unless the expression 'directly' is used, one or more other parts may be positioned between the two parts.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal relationship is described with 'after', 'following', 'after', 'before', etc. Unless the expression "

To describe various elements, expressions such as 'first', 'second', etc. are used, but these elements are not limited by these terms. These terms are only used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

The term “at least one” should be understood to include all possible combinations from one or more related items.

Each feature of the various embodiments of the present invention may be partially or wholly combined or combined with each other, technically various interlocking and driving are possible, and each of the embodiments may be implemented independently of each other or may be implemented together in a related relationship. may be

1 is a schematic cross-sectional view of a multilayer plating 10 according to an embodiment of the present invention.

As shown in FIG. 1 , the multilayer plating 10 includes a substrate to be plated 100 - a cyanide plating layer 200 - a post plating layer 300 . Copper cyanide plating is mainly performed on a metal substrate, but is not limited thereto, and may be performed on a non-metal substrate. The post-plating layer 300 may be formed of various metals such as copper, iron, nickel, chromium, cobalt, silver, or gold, but the present invention is not limited thereto.

The present invention relates to a copper cyanide plating solution and a copper cyanide plating method for forming a cyanide copper plating layer 200 in a multi-layer plating (10).

According to an embodiment of the present invention, the copper bronze plating solution includes a copper cyanide compound and an additive.

In the present invention, the copper cyanide compound is not only copper cyanide (CuCN), but also copper cyanide (CuCN) reacts with sodium cyanide (NaCN) or potassium cyanide (KCN) sodium cyanide (Na ₂ Cu(CN) ₃ ) or Potassium cyanide (K ₂ Cu(CN) ₃ ) is said to be included, and copper cyanide (CuCN) refers to copper for plating extracted with a complex salt of copper (Gu) and cyanide groups. Copper cyanide (CuCN) is also called cyanide copper.

The plating solution is called a plating bath when it is placed in a plating bath, and the plating solution is usually called a plating bath.

According to an embodiment of the present invention, the copper cyanide compound includes copper cyanide (CuCN), sodium cyanide (Na ₂ Cu(CN) ₃ ), potassium cyanide (K ₂ Cu(CN) ₃ ), or a mixture thereof. can do.

Sodium cyanide (Na ₂ Cu(CN) ₃ ) is a complex salt formed by combining copper cyanide (CuCN) with sodium cyanide (NaCN). can Copper cyanide (CuCN) and sodium cyanide (NaCN) are dissolved in a solvent as shown in Scheme 1 below to form a complex salt in the same form as _{sodium cyanide (Na 2} Cu(CN) _{3 ) and are present in the plating solution.} In addition, in addition to Na ₂ Cu(CN) ₃ (sodium copper cyanide) of the following Reaction Scheme 1, the residual sodium cyanide (NaCN) after the reaction forms free cyanide in the form of sodium cyanide and is present in the plating solution. .

<Scheme 1>

CuCN (copper cyanide) + 2NaCN (sodium cyanide) → Na ₂ Cu(CN) ₃ (copper sodium cyanide)

Potassium cyanide (K ₂ Cu(CN) ₃ ) is a complex salt formed by combining copper cyanide (CuCN) with potassium cyanide (KCN). The copper cyanide compound may include copper cyanide (CuCN) and potassium cyanide (KCN). can Copper cyanide (CuCN) and potassium cyanide (KCN) are dissolved in a solvent as shown in Scheme 2 below to form a complex salt in the same form as _{copper cyanide potassium (K 2} Cu(CN) _{3 ), and are present in the plating solution.} In addition, in addition to K ₂ Cu(CN) ₃ (potassium copper cyanide) of the following Reaction Formula 2, the remaining potassium cyanide (KCN) after the reaction forms free cyanide in the form of free cyanide in the plating solution my existence

<Scheme 2>

CuCN(Copper Cyanide) + 2KCN(Potassium Cyanide) → K ₂ Cu(CN) ₃ (Potassium Cyanide)

When drying the copper cyanide plating solution, copper cyanide (CuCN) alone does not dissolve in water. Therefore, sodium cyanide (NaCN) or potassium cyanide (KCN) is added together with copper cyanide (CuCN), so as in Scheme 1 or 2, sodium cyanide (Na ₂ Cu(CN) ₃ ) or potassium cyanide (K _{2 )} Cu(CN) ₃ ) is dissolved by forming a complex salt of the same type. During plating, plating may be performed by managing the composition of the plating solution based on the concentration of residual sodium cyanide or potassium cyanide remaining freed from the plating solution after the reaction of forming a complex salt with copper cyanide and copper cyanide.

Copper (Copper) used in copper cyanide plating may be either a +1 ^valent ion (Cu 1+ ) or a + divalent ion (Cu ²⁺ ), but it is preferable to include a ^{+1 valent copper ion (Cu 1+ ).} desirable.

^{Copper cyanide plating containing +1 valent} copper ions (Cu 1+ ) is alkaline, the average deposition rate is 2.37 g/1AH (1AH is the unit of current density conducted per hour), and It has excellent adhesion. On the other hand, copper ^{cyanide plating containing +2-} valent copper ions (Cu 2+ ) is acidic, has a relatively slow deposition rate with an average deposition rate of 1.186 g/1AH, and has poor adhesion to metal substrates. Therefore, it is advantageous for the +1 to include copper ions (Cu ^{1+ ).}

Copper cyanide plating solution may contain copper cyanide (CuCN) at a concentration of 10 g/L to 50 g/L, and preferably, a concentration of 20 g/L to 40 g/L.

When the concentration of copper cyanide (CuCN) in the plating solution is less than 10 g/L, the thickness of the plating layer becomes too thin, or the time it takes to form a sufficient plating layer increases. Conversely, when the concentration of copper cyanide (CuCN) in the plating solution exceeds 50 g/L, the concentrations of sodium cyanide and potassium cyanide in the plating solution are reduced, and accordingly, the dissolving power of the anode is lowered, so that the passivation phenomenon of the anode is reduced. This causes uneven precipitation on the object to be plated.

Sodium cyanide and potassium cyanide may be added at a concentration of 25 g/L to 65 g/L with respect to the total plating solution, and are preferably added at a concentration of 40 g/L to 50 g/L.

In the copper cyanide plating solution, either one of sodium cyanide and potassium cyanide may be added, or both of the cyanide compound may be added. Sodium cyanide and potassium cyanide are for dissolving copper cyanide in a solvent, and the concentration of sodium cyanide, potassium cyanide, or a mixture thereof may be added at a concentration of 25 to 65 g/L with respect to the copper cyanide plating solution.

When the concentration of sodium cyanide, potassium cyanide, or a mixture thereof is less than 25 g/L, sufficient sodium cyanide or potassium cyanide compound is not contained in the plating solution, so that a uniform plating layer is not formed. Conversely, when the concentration exceeds 65 g/L, the generation of a toxic gas in the form of highly toxic hydrogen cyanide (HCN) remarkably increases, and the plating solution is strongly alkalized, so that the plating is not sufficiently performed in the low current density region.

In the actual process, the concentration of the copper cyanide compound in the plating solution is not the concentration of sodium cyanide, potassium cyanide, or a mixture thereof, but the glass cyanide that is present in the plating solution after forming a complex salt with copper cyanide and copper cyanide Control based on the concentration of free cyanide in sodium and/or potassium free cyanide. In general, the concentration of residual free cyanide in the plating solution may be adjusted to 10 to 50 g/L, preferably 15 to 20 g/L.

According to an embodiment of the present invention, the copper cyanide plating solution includes an additive to improve adhesion of the copper plating layer and control glossiness.

On the other hand, when the glossiness of the copper plating layer is too low, the adhesion of the copper plating layer is increased, but there is a problem in that the glossiness of the post plating layer is decreased. On the other hand, when the glossiness of the copper plating layer is too high, a film of the organic raw material of the brightener is formed on the surface of the deposited copper plating layer, so that adhesion with the post plating layer is reduced, and the post plating layer may be easily separated. Accordingly, the glossiness of the copper plating layer needs to be uniformly maintained over the entire surface of the copper plating layer within a certain numerical range.

Therefore, in order to maintain proper adhesion while improving the glossiness of the post-plated layer, the average gloss of the copper-plated layer is preferably 40 to 75 GU.

According to one embodiment of the present invention, in order to improve the adhesion of the copper plating layer and control the glossiness, the copper cyanide plating solution includes a semi-gloss additive.

In general, the brightening agent included in the copper cyanide plating solution improves the overall glossiness of the copper plating layer surface and performs a leveling action (surface smoothness) to improve the glossiness in the post plating process (mainly nickel plating). .

Here, the leveling refers to the action of the plating solution to flatten the microscopic irregularities of the substrate, the streak of polishing, and the like, and the leveling action is referred to as a smoothing action.

The smoothing action by the semi-glossy additive of the present invention is due to the consumption of electrolytic diffusion of the additive. When a low-concentration additive reaches the surface and is electrolytically consumed, the amount of additive supplied to the surface is determined by the thickness of the diffusion layer at the interface. That is, the consumption amount of the additive is small in the concave portion where the diffusion layer is thick, and the consumption amount of the additive in the concave portion where the diffusion layer is thin as the opposite layer is increased. In other words, the current consumed for decomposition of the additive is small in the concave part and increases in the concavity part. In terms of the amount of plating deposition, the concave part precipitates more than the concave part.

According to an embodiment of the present invention, the semi-gloss additive includes a 3-hexaine-2,5-diol compound and a sulfur compound. The semi-glossy additive of the present invention is a one-component additive that does not contain heavy metals, and it is easy to use and manage in fixing the plating, and the plating process can be performed even at a low temperature of ^{30 to 50 o C.} Due to this, the production cost is reduced and the process efficiency is increased.

3-Hexane-2,5-diol is represented by the following formula (1).

<Formula 1>

The 3-hexaine-2,5-diol compound acts as a main carrier in the copper cyanide plating solution, and when a current is applied, the copper (Cu) ion precipitated particles in the plating solution precipitated on the surface of the body to be plated (cathode). Adjust the glossiness of the plating surface by refining it. Due to this, a semi-glossy precipitation surface is formed evenly over the whole current density area from the high current portion to the low current portion. That is, the gloss deviation between the high current section and the low current section is reduced.

In addition, the 3-hexan-2,5-diol compound lowers the surface tension of the precipitation surface to reduce adhesion and stain defects that may occur during post-plating, and forms a semi-glossy precipitation surface to form a gloss in the post-plating process Don't let the speed slow down.

The 3-hexaine-2,5-diol compound may be added at a concentration of 0.5 g/L to 10 g/L in the plating solution, preferably 1.5 g/L to 7 g/L, more preferably 2 g It is preferably added at /L to 4 g/L.

When the concentration of the 3-hexaine-2,5-diol compound in the plating solution is less than 0.5 g/L, the average glossiness of the copper plating layer has a value of less than 40 GU, and the gloss deviation and surface tension of the gloss layer surface increase. will do Conversely, when the concentration of the 3-hexaine-2,5-diol compound in the plating solution exceeds 10 g/L, the glossiness of the copper plating layer exceeds 75 GU.

According to an embodiment of the present invention, the sulfur compound included as a semi-glossy additive in the copper cyanide plating solution is at least one of sodium saccharin, sodium vinyl sulfonate, and sodium allyl sulfonate. may include any one. In particular, the sulfur compound preferably includes sodium saccharin, but one embodiment of the present invention is not limited thereto.

Sodium saccharin may be represented by Formula 2 below, sodium vinylsulfonate may be represented by Formula 3 below, and sodium allylsulfonate may be represented by Formula 4 below.

<Formula 2>

<Formula 3>

<Formula 4>

Sulfur compounds act as carriers and brighteners in the copper cyanide plating solution.

However, looking at the structures represented by Chemical Formulas 2 to 4, sulfur compounds commonly contain a single sulfur (S) atom, and when these compounds containing a sulfur atom are added to a plating solution, they have a leveling action or luster action than a brightener. is low, and the activity of the precipitation surface after plating is excellent, and stress is not generated inside the copper plating layer. In addition, there is an effect of improving the plating coverage of the low current density region.

In particular, sodium saccharin increases the ductility of the plating layer deposited on the surface of the material to relieve the stress caused by the additive raw materials, and reduces the occurrence of surface hardening (film) caused by the organic raw materials to form a coating layer and increase the coverage of

The sulfur compound may be added at a concentration of 0.75 g/L to 4.00 g/L in the plating solution.

When the concentration of the sulfur compound in the plating solution is less than 0.75 g/L, the ductility of the entire plating layer is lowered, and the entire surface of the plating layer is not smooth, and surface precipitation in the form of spots occurs. Conversely, when the concentration of the sulfur compound in the plating solution exceeds 4.00 g/L, the average glossiness of the plating layer decreases to less than 40 GU.

According to an embodiment of the present invention, the semi-gloss additive may further include N-polyether (N-Polyether) and L-polyether (L-Polyether). At least one of N-polyether and L-polyether may be included.

Among the polyether-based compounds, N-polyether and L-polyether, N-polyether acts as a brightening accelerator, and L-polyether compound is a major carrier, 3-hexa As an auxiliary carrier supporting phosphorus-2,5-diol, it acts as an auxiliary carrier to refine the particles of copper (Cu) ions that are precipitated. The polyether-based compound imparts uniform gloss to the copper plating layer from the high current density region to the low current density region, and at the same time maintains the uniform semi-glossiness of the copper plating layer by assisting 3-hexan-2,5-diol. to reduce gloss deviation.

In addition, the polyether-based compound functions as a surfactant and lowers the surface tension of the plating solution, thereby preventing a drag-out phenomenon when the object to be plated is taken out of the plating bath after plating, and a large amount of It reduces the amount of plating solution smeared. Due to this, it is possible to reduce the consumption of the plating solution and additives.

N-polyether and L-polyether may be added at a concentration of 0.015 g/L to 0.45 g/L, respectively, based on the plating solution.

When the concentration of each of the N-polyether and L-polyether is less than 0.015 g/L, the glossiness of the low current density region deteriorates, and the gloss deviation increases. In addition, when the concentration of each of the N-polyether and L-polyether exceeds 0.45 g/L, unevenness occurs on the surface of the plating layer.

According to an embodiment of the present invention, the semi-glossy additive further comprises at least one of butynediol ethoxylate and 2-butyne-1,4-diol can do. In addition, the semi-glossy additive may further include glycine.

Butynediol ethoxylate, 2-butyne-1,4-diol and glycine act as carriers and brighteners in the copper bronze plating solution. However, butynediol ethoxylate, 2-butyne-1,4-diol and glycine have a characteristic that, unlike general brighteners, they have a luster action on the plating layer, but form a small amount of stress.

The concentration of at least one of butynediol ethoxylate and 2-butyne-1,4-diol may be added at 0.075 to 0.375 g/L based on the plating solution, and glycine may be added at 0.075 g/L to 0.525 g/L based on the plating solution. L may be added.

According to an embodiment of the present invention, the semi-glossy additive included in the copper cyanide plating solution may further include a surfactant. In this case, the surfactant preferably includes a fluorinated surfactant, and more preferably includes a potassium perfluorobutane sulfonate compound. Potassium perfluorobutanesulfonate is a fluorine-based surfactant and is a fluorine-based compound that does not contain harmful substances.

Potassium perfluorobutanesulfonate is represented by the following formula (5).

<Formula 5>

In order to improve the adhesion between the copper plating layer and the post plating layer, a fine concavo-convex surface may be formed on the surface on which copper ions are deposited. A fluorine-based surfactant may be used as a method for realizing a fine concavo-convex surface on the precipitation surface.

By finely etching the surface of the plating layer, the fluorine-based surfactant can form a fine concavo-convex surface and at the same time lower the surface tension of the plating solution to a maximum of 41 dyn/cm depending on the amount added. By lowering the surface tension of the plating solution, the drag-out phenomenon that occurs when the object to be plated is taken out of the plating bath after plating can be reduced, thereby reducing the consumption of the plating solution and additives.

According to an embodiment of the present invention, the concentration of the fluorine-based surfactant may be added to 0.05 g/L to 0.15 g/L in the plating solution.

When the concentration of the fluorine-based surfactant in the plating solution is less than 0.05 g/L, the degree of formation of the fine concavo-convex surface is significantly reduced, and the surface tension is also meaningless because there is no difference. Moreover, when it exceeds 0.15 g/L, since an over-etching phenomenon occurs, glossiness falls.

According to an embodiment of the present invention, the copper cyanide plating solution may further include at least one or more of an organic acid salt and an inorganic acid salt.

The organic acid salt is at least one of formate, carbonate, acetate, tartrate, citrate, gluconate and L-glutamate. includes one In particular, it is preferable to include at least one of potassium sodium tartrate, sodium tartrate, potassium tartrate, sodium carbonate, and potassium carbonate. However, one embodiment of the present invention is not limited thereto.

The inorganic acid salt includes at least one of phosphate, pyrophosphate, alkali hydroxide compound, and borate. In particular, it is preferable to include at least one of sodium hydroxide and potassium hydroxide. However, one embodiment of the present invention is not limited thereto.

Conductive salts such as organic acid salts and inorganic acid salts are added to increase conductivity in the plating solution, and serve as a buffer. Therefore, the fluctuation range of the pH of the plating solution is reduced during the plating process, so that the plating solution can be easily managed. In addition, organic acid salts and inorganic acid salts have high conductivity and increase the current density, thereby improving throwing power.

According to an embodiment of the present invention, the total concentration of the organic acid salt and the inorganic acid salt may be added to 30 g/L to 80 g/L in the plating solution.

When the concentration of organic acid salts and inorganic acid salts in the plating solution is less than 30 g/L, the deposition rate of the plating layer during plating is lowered, and when it exceeds 80 g/L, highly toxic hydrogen cyanide (HCN) form generation of harmful gas increases, and the plating solution becomes strongly alkaline, resulting in non-plating in the low current density region.

Hereinafter, a copper cyanide plating method according to another embodiment of the present invention will be described in detail with reference to FIG. 2 .

2 is a flowchart of a copper bronze plating method using the copper cyanide plating solution of the present invention.

The copper chrysanthemum plating method of the present invention comprises the steps of preparing a material to be plated; Preparation of copper cheonghwa plating solution; and plating copper cyanide on the surface of the substrate to be plated through electroplating using a copper cyanide plating solution.

Specifically, the step of preparing the substrate to be plated includes degreasing treatment and activation treatment using ultrasonic waves and/or alkali on the surface of the substrate to be plated. In addition, polishing treatment and oxidation treatment of the surface of the substrate to be plated may be included. The pretreatment in the step of preparing the object to be plated is not limited thereto, and a pretreatment process generally performed in the plating technology field may be added, and some of the treatments described above may be excluded.

In the step of preparing the copper cyanide plating solution, a copper cyanide compound is first dissolved in a solvent to prepare a copper cyanide plating solution. The copper cyanide compound may include copper cyanide (CuCN), sodium cyanide (Na ₂ Cu(CN) ₃ ), potassium cyanide (K ₂ Cu(CN) ₃ ), or a mixture thereof.

Copper cyanide (CuCN) is insoluble in water, so it is dissolved in the form of sodium cyanide (Na ₂ Cu(CN) ₃ or potassium cyanide (K ₂ Cu(CN) ₃ ). Sodium cyanide (Na ₂ Cu() CN) ₃ and/or potassium cyanide (K ₂ Cu(CN) ₃ ) is obtained by adding copper cyanide and sodium cyanide (NaCN) and/or potassium cyanide (KCN) to a solvent to obtain sodium copper cyanide (Na ₂ Cu(CN) ) ₃ and/or potassium cyanide (K ₂ Cu(CN) ₃ ) form a complex salt form, and sodium copper cyanide (Na ₂ Cu(CN) ₃ and/or copper cyanide potassium (K ₂ Cu(CN) CN) ) ₃ ) is dissolved in a solvent and exists in the form of an aqueous solution The solvent is mainly water, but one embodiment of the present invention is not limited thereto.

In the copper cyanide plating solution, copper cyanide may be added at a concentration of 10 g/L to 50 g/L based on the total copper cyanide plating solution, and at least one of sodium cyanide and potassium cyanide is a total of 25 g/L to 65 g/L L, preferably 40 g/L to 50 g/L. However, the exemplary embodiment of the present invention is not limited thereto, and sodium copper cyanide or potassium cyanide may be directly added to the copper bronze plating solution. In general, during plating, the concentration of the copper cyanide plating solution is based on the concentration of free cyanide of sodium free cyanide and/or potassium free cyanide, which is freed from the plating solution after forming a complex salt with the copper cyanide and copper cyanide. can be managed as The concentration of residual free cyanide in the plating solution may be adjusted to 10 to 50 g/L, preferably 15 to 20 g/L.

According to another embodiment of the present invention, the copper bronze plating solution includes 3-hexain-2,5-diol and a sulfur compound in addition to the copper bronze compound. 3-Hexane-2,5-diol may be added at a concentration of 0.5 g/L to 10 g/L with respect to the total copper bronze plating solution, and the sulfur compound may be added at a concentration of 0.75 g/L to 4.00 g based on the total copper cyanide plating solution. It can be added at a concentration of /L. However, one embodiment of the present invention is not limited thereto.

The sulfur compound may include at least one of sodium saccharin, sodium vinyl sulfonate, and sodium allyl sulfonate.

According to another embodiment of the present invention, the copper cyanide plating solution contains 0.015 g/L to 0.45 g/L of N-polyether and 0.015 g/L to 0.45 g/L of the copper cyanide plating solution. It may further include an L-polyether (L-Polyether) compound. At least one of an N-polyether compound and an L-polyether may be included.

According to another embodiment of the present invention, the copper chrysanthemum plating solution may include at least one of butynediol ethoxylate and 2-butyne-1,4-diol, and butynediol ethoxylate and 2-butyne-1 The total concentration of ,4-diol may be added from 0.075 g/L to 0.375 g/L. In addition, the copper cheongsam plating solution may further include glycine of 0.075 g/L to 0.525 g/L.

According to another embodiment of the present invention, the copper cyanide plating solution may further include a surfactant. In this case, the surfactant preferably includes a fluorinated surfactant, and more preferably includes a potassium perfluorobutane sulfonate compound. The fluorine-based surfactant is added in an amount of 0.05 g/L to 0.15 g/L with respect to the total copper cyanide plating solution.

According to another embodiment of the present invention, the copper cyanide plating solution may further include at least one of an organic acid salt and an inorganic acid salt, and the total concentration of the organic acid salt and the inorganic acid salt is 30 g/L to 80 g/L. may be added.

As described above, the copper cyanide plating solution of the present invention can be prepared by essentially adding the copper chrysanthemum compound, the 3-hexaine-2,5-diol compound, and the sulfur compound to the aqueous solution and selectively adding other additives. .

In the step of plating the copper cyanide on the surface of the substrate to be plated, the surface of the substrate to be plated is electroplated using the prepared copper cyanide plating solution. Copper cyanide plating is to form a base plating before forming a post plating layer, and strike plating is mainly used. However, one embodiment of the present invention is not limited thereto.

The copper cyanide plating of the present invention may be performed in the same manner as the strike plating generally used in the plating technology field.

However, as a copper cyanide plating solution of the present invention is the addition of additives of one-pack type, which comprises a 3-hexahydro-2,5-diol and a sulfur compound, a copper cyanide plating, according to the method of the invention, from 35 to 45 ^o C Copper cyanide plating may be performed under mild conditions, and the current density applied between the positive electrode plates may be adjusted ^{to 0.5 to 5 A/dm 2 .} In addition, the pH of the plating solution may be adjusted to 12 to 13, and plating is performed for 5 to 20 minutes to form a plating layer.

By using the one-component additive of the present invention, the processing operation is easy and the replenishment cost of the additive is reduced. In addition, energy cost can be reduced because plating can be performed under low temperature conditions (35 to 45 ^o C) compared to copper cyanide plating using a multi-component brightener in general, ^{compared to plating at 65 o C.} In addition, it is possible to form a copper plating layer having an average gloss of 40 to 75 GU and excellent adhesion.

A plated article having a copper bronze plating layer of the present invention was manufactured by the above method. Thereafter, by performing post-plating with nickel, chromium, and other alloys on the surface of the copper cyanide-plated plated article, a multi-layer plated plated article can be manufactured.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples. However, the following Examples and Comparative Examples are only for helping the understanding of the present invention, and the scope of the present invention is not limited by the Examples or Comparative Examples.

< Examples and Comparative Examples >

Comparative Example 1

A copper cyanide plating solution that was dry bathed with the following composition was prepared without adding 3-hexaine-2,5-diol, which is a semi-glossy additive.

Copper cyanide 30g/L

Sodium cyanide 45g/L

Potassium sodium tartrate 15g/L

Potassium hydroxide 10g/L

Potassium carbonate 10g/L

Comparative Example 2

3-Hexane-2,5-diol was diluted in DI water to prepare a 10% aqueous solution (100 g/L). Thereafter, a copper chrysanthemum plating solution was prepared in the same composition as in Comparative Example 1, except that 5 ml/L of a 10% aqueous solution of 3-hexaine-2,5-diol was added. The concentration of 3-hexaine-2,5-diol added based on the plating solution was 0.5 g/L.

Comparative Example 3

A copper chrysanthemum plating solution was prepared in the same composition as in Comparative Example 1, except that 10 ml/L of 3-hexaine-2,5-diol 10% aqueous solution was added. The concentration of 3-hexaine-2,5-diol added based on the plating solution was 1.0 g/L.

Comparative Example 4

A copper chrysanthemum plating solution was prepared in the same composition as in Comparative Example 1, except that 15 ml/L of a 10% aqueous solution of 3-hexaine-2,5-diol was added. The concentration of 3-hexaine-2,5-diol added based on the plating solution was 1.5 g/L.

Comparative Example 5

A copper chrysanthemum plating solution was prepared in the same composition as in Comparative Example 1, except that 15 ml/L of a 15% aqueous solution of 3-hexaine-2,5-diol was added. The concentration of 3-hexaine-2,5-diol added based on the plating solution was 2.25 g/L.

Using the plating solutions prepared in Comparative Examples 1 to 5, a Hull Cell Test was performed to check the plating difference according to the amount of 3-hexaine-2,5-diol added. Through the Hullsel test, the optimal current density in electroplating can be found, and the gloss deviation can be calculated by comparing the glossiness according to the difference in current density.

The Hullcell test may be performed in the form shown in FIG. 3 . In the Hullcell test, when a plating solution is put into a test tank in which the anode and the cathode are opposed to each other at a certain angle, the current density is continuously changed in each part of the cathode. Therefore, the state of the plating surface obtainable from the cathode also changes accordingly. At this time, if the location of the preferred plating surface is found, the optimum current density can be estimated because the current used is already known.

Specimens for carrying out the Hullcell test were subjected to ultrasonic degreasing, alkaline electrolytic degreasing, and activation treatment prior to testing. The detailed conditions of the pretreatment are as follows.

[Ultrasonic degreasing]

DC #25(C): 100ml/L, Temperature: Room temperature, Treatment time: 30 seconds

[Alkaline electrolytic degreasing]

EC 100 F: 70 g/L, temperature: 60 ^o C, current density: 3A/dm ² , treatment time: 1 minute

[Activation processing]

AC 303: 50ml/L, temperature: room temperature, treatment time: 10 seconds

In addition, the Hullcell test in the present invention was carried out by plating for 5 minutes using a plating solution without ^{stirring at 45 o} C, a current density of 1A/dm ^{2 .}

The Hullcell test was performed under the above conditions using the copper cyanide plating solutions of Comparative Examples 1 to 5, and the surface of the plated specimen was photographed. A photograph taken is shown in FIG. 4 .

As can be seen in FIG. 4 , as the amount of 3-hexaine-2,5-diol increased, it was observed that a semi-gloss copper plating layer was formed from the high current density region to the medium current density region, and 15% 3- When adding 15 ml/L of aqueous solution of hexane-2,5-diol (2.25 g/L of 3-hexain-2,5-diol based on plating solution), the most uniform semi-gloss copper from high current density to low current density It can be observed that the plating layer is formed. In order to check the change in glossiness before and after addition, the glossiness of the specimen was measured with a glossmeter.

The glossiness of the specimens plated with the plating solution of Comparative Examples 1 to 5 was measured using a gloss ^{meter (Elcometer, J480T-6, (60 O )).} The measured glossiness of Comparative Examples 1 to 5 is shown in Table 1 below.

current density part
(Current density area) Glossiness of Comparative Example 1
(GU) Glossiness of Comparative Example 2
(GU) Glossiness of Comparative Example 3
(GU) Glossiness of Comparative Example 4
(GU) Glossiness of Comparative Example 5
(GU) 5A (high current part) 3 17.7 26.8 38.8 41.2 3A (medium current part) 2.7 15.1 25.2 33.3 35.8 1A (low current part) 2.1 13.8 24.8 29.1 32.9 average gloss 2.6 15.5 25.6 33.7 36.6

As can be seen in FIG. 4 and Table 1, Comparative Examples 2 to 5 in which 3-hexaine-2,5-diol was added formed a copper plating layer having uniform semi-gloss properties as a whole, but the average glossiness was less than 40 GU. . In addition, the coating condition of the low current density part was not good, it was not smooth as a whole, and surface precipitation in the form of a spot was observed.

Example 1

To the plating solution having the same composition as in Comparative Example 5, 2.25 g/L of sodium saccharin was added to prepare a copper chrysanthemum plating solution of Example 1. The detailed composition of the copper cyanide plating solution of Example 1 is as follows.

Copper cyanide 30g/L

Sodium cyanide 45g/L

Potassium sodium tartrate 15g/L

Potassium hydroxide 10g/L

Potassium carbonate 10g/L

3-Hexane-2,5-diol 2.25 g/L

Sodium saccharin 2.25 g/L

As described above, using the copper cyanide plating solution prepared in Example 1, the Hullcell test was performed, and the conditions for pretreatment and pretreatment of the specimen were the same as those of Comparative Examples 1 to 5.

A photograph of the Hullcell test result of Example 1 is shown in FIG. 5, and the glossiness of the plated specimen is shown in Table 2.

current density part
(Current density area) Example 1
(GU) 5A (high current part) 48.7 3A (medium current part) 43.8 1A (low current part) 36.7 average gloss 43.1

As a result of the test, in Example 1, a plating layer having excellent throwing power was observed compared to Comparative Examples 2 to 4 in which only 3-hexaine-2,5-diol was added, and the coating power was excellent even at low current, and from high current density to low current. A semi-glossy copper plating layer that was uniform to density was deposited. As such, compared to the precipitation surfaces and glossiness of Comparative Examples 1 to which 3-hexain-2,5-diol was not added and Comparative Examples 2 to 5 in which 3-hexain-2,5-diol was added alone, sodium saccharin It can be seen that Example 1 in which was added together has a smoother surface precipitation and increased gloss.

Examples 2 to 9

A semi-glossy additive was additionally added to the same composition as in Comparative Example 1. Semi-glossy additives are added to the entire plating solution, 3-hexan-2,5-diol, sodium saccharin, sodium vinylsulfonate, sodium allylsulfonate, N-polyether, L-polyether, butynediol ethoxylate, and glycine. was added according to the composition of Table 3 below to prepare the copper chrysanthemum plating solutions of Examples 2 to 9.

additive Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 3-Hexane-2,5-diol
(g/L) 2.25 2.25 2.25 2.25 2.25 2.25 2.25 2.25 sodium saccharin
(g/L) 0.75 1.5 2.25 3.0 2.25 2.25 3.75 2.25 Sodium vinylsulfonate
(g/L) 0.075 - 0.075 - 0.075 - - - Sodium Allylsulfonate
(g/L) 0.075 0.075 - 0.075 - 0.075 - - Butynediol ethoxylate
(g/L) 0.075 0.15 - 0.225 0.225 0.225 0.225 0.225 N-polyether
(g/L) 0.075 0.075 - 0.15 0.375 0.225 0.075 0.225 L-polyether
(g/L) 0.15 - 0.075 0.15 0.375 0.225 0.075 0.225 glycine
(g/L) 0.075 0.15 0.225 0.225 0.15 0.225 0.075 0.15

Using the copper cyanide plating solutions of Examples 2 to 9 prepared as described above, the Hullcell test was performed, and the conditions for pretreatment and pretreatment of the specimen were the same as those of Comparative Examples 1 to 5.

As a result of the test, excellent throwing power was observed in Examples 2 to 9, and the coating power was excellent even at low current, and a semi-glossy copper plating layer was deposited uniformly from high current density to low current density.

The photos of the Hullcell test results of Examples 2 to 9 are shown in FIG. 6, and the glossiness of the plated specimen is shown in Table 4. The glossiness unit in Table 4 is GU.

current density part
(Current density area) Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 5 A/dm ² (high current part) 61.2 62.8 53.8 65.4 81.5 68.4 62.1 67.8 3 A/dm ² (medium current part) 48.9 52.1 43.8 53.5 73.4 57.2 53.7 60.6 1 A/dm ² (low current part) 41.2 43.1 39.8 46.8 62.4 48.5 45.5 51.7 average gloss 50.4 52.7 45.8 55.2 72.4 58.0 53.8 60.0

As described above, the surface smooth compared to the precipitation surfaces and glossiness of Comparative Examples 1 to which 3-hexain-2,5-diol was not added and Comparative Examples 2 to 5 in which 3-hexain-2,5-diol was added alone. It can be seen that the precipitation and glossiness are increased. In addition, it can be seen that the average gloss is improved compared to Example 1 in which only 3-hexaine-2,5-diol and sodium saccharin are added.

Comparative Example 6

5 ml/L and 10 ml/L, respectively, of multi-component brighteners C Brite #10 and C Brite #30 (JCU, Japan), not semi-glossy additives, were added to the copper chrysanthemum plating solution having the same composition as in Comparative Example 1. A plating solution was prepared.

As described above, using the prepared copper cyanide plating solution of Comparative Example 6, the Hullcell test was performed, and the conditions of pretreatment and pretreatment of the specimen were the same as before.

A photograph comparing the results of the Hullcell test of Comparative Example 6 and Example 9 is shown in FIG. 7 , and the glossiness of the plated specimen is shown in Table 5 below.

current density part
(Current density area) Glossiness of Comparative Example 6
(GU) Glossiness of Example 9
(GU) 5A (high current part) 198 67.8 3A (medium current part) 49 60.6 1A (low current part) 1.9 51.7 average gloss 83.0 60.0

As can be seen in Figures 7 and 5, in Comparative Example 6 to which a gloss agent of JCU of Japan was added, the glossiness of the high current density region is good, but the glossiness of the medium current density to the low current density region is significantly higher than that of the high current density region. decreased. On the other hand, in Example 9, in which the one-component semi-gloss additive was added, the glossiness of the high current density region was relatively lower than that of Comparative Example 6, but a uniform semi-glossy plating layer was formed from the high current density region to the low current density region. you can check what you are doing. As such, Example 9 reduced the gloss deviation for each current density region.

Example 10

A copper cyanide plating solution was prepared by adding 0.05 g/L of potassium perfluorobutanesulfonate as a fluorine-based surfactant to the same composition as in Example 9.

Example 11

A copper cyanide plating solution was prepared by adding 0.15 g/L of potassium perfluorobutanesulfonate as a fluorine-based surfactant to the same composition as in Example 9.

Using the copper cyanide plating solutions of Examples 10 and 11 prepared in this way, copper cyanide plating was performed on the specimen. In addition, for comparison, the same specimen was plated using the copper chrysanthemum plating solution of Example 9.

The plating surface roughness of the specimens plated with the plating solution of Examples 9 to 11 was visually observed. 8 is a photograph of the surfaces of the specimens of Examples 9 to 11 taken with an electron microscope at 550 magnification.

As can be seen from FIG. 8 , Example 10 in which potassium perfluorobutanesulfonate was added had a finer uneven surface than Example 9 in which potassium perfluorobutanesulfonate was not added, and Example 11 in which the addition amount was 0.15 g/L It can be seen that a surface having finer and more uniform fine irregularities was formed than in Example 10.

In order to confirm the difference in the surface tension (dyn/cm) of the copper cyanide plating solution depending on whether potassium perfluorobutanesulfonate was added and the amount added, the surface tension (dyn/cm) of the plating solutions of Examples 9 to 11 using a water meter cm) was measured.

The surface tension of the plating solution can be obtained by Equation 1 below.

[Equation 1]

Surface tension (dyn/cm) = [Surface tension of water x dripping amount of water x specific gravity of plating solution (Sp.Gr)]/[loading amount of plating solution x specific gravity of water (Sp.Gr)]

The surface tensions of Examples 9 to 11 calculated through the water meter and Equation 1 are shown in Table 6 below.

surface tension
(dyn/cm) Example 9 72 Example 10 61 Example 11 31

As can be seen in Table 6, Example 10 in which 0.05 g/L of potassium perfluorobutanesulfonate was added had a 9 dyn/cm decrease in surface tension compared to Example 9 without addition of 0.05 g/L, and 0.15 g/L was added. 11 was confirmed to be reduced by 41 dyn/cm compared to Example 9 in which no addition was made.

Using the copper cyanide plating solution of Examples 9, 11 and Comparative Example 6, the iron specimen was plated. The applied current density was all 1A/dm ² , and the thickness of the plating layer was all unified at 5 μm. However, in Examples 9 and 11, the plating temperature ^{was adjusted to 45 o} C, and in Comparative Example 6, the plating temperature ^{was adjusted to 65 o} C for plating. This is because, unlike the semi-glossy additive of the present invention, plating does not proceed with the plating solution containing the brightener at a low temperature.

The photos of the iron specimens plated with the copper cyanide plating solution of Examples 9, 11 and Comparative Example 6 are shown in FIG. 9 . In addition, the surface roughness Rq (RMS) value of each specimen was measured for the plated iron specimen using XE 100 manufactured by PSIA.

The measured surface roughness Rq (RMS) values are shown in Table 7 below.

Rq(RMS)
(nm) Comparative Example 6 101.088 Example 9 90.718 Example 11 55.693

As a result of measuring the surface roughness (Rq) value for each plating solution with AFM (Atomic Force Microscope), the composition of the one-component copper cyanide plating additive and potassium perfluorobutanesulfonate was lower than that using JCU's brightener of Japan. Surface roughness values were measured. Through this, it is confirmed that when the semi-gloss additive of the present invention is added, a fine uneven (fine etching) surface can be realized compared to the conventional varnish, and a copper cyanide plating surface having strong adhesion with the post-plating can be secured. did In addition, by additionally including potassium perfluorobutanesulfonate, it is possible to have a finer concave-convex surface and adhesion. This is because the finest concave-convex (fine etching) surface was realized on the surface of the plating precipitation among the three samples, and after plating and It has become possible to secure a copper cyanide plating surface with strong adhesion.

In order to confirm the effect of the experimental results on the post-plating process, post-plating was performed on the copper chrysanthemum-plated iron specimens of Example 11 and Comparative Examples 1 and 6.

A bright nickel plating solution was used for the post plating, and the composition and plating conditions of the bright nickel plating solution are as follows. In addition, the thickness of the plating layer of the formed copper cyanide plating and nickel plating is shown in Table 8 below.

Nickel sulfate 30g/L

Nickel chloride 45g/L

Boric acid 15g/L

Brightener 1 (Nikal #1 of Serchem Co., Ltd.) 10ml/L

Brightener 2 (NIKAL #2 from Serchem Co., Ltd.) 0.5ml/L

Current density: 2A/dm ²

pH: 4.0 to 4.4

Temperature: 58 ^o C

Plating time: 10 minutes

plating thickness
(μm) bronze plating polished nickel plating Comparative Example 1 5.21 7.38 Comparative Example 6 5.25 7.51 Example 11 5.22 7.46

For the plated articles of Example 11 and Comparative Examples 1 and 6 prepared as described above, (i) visual confirmation and measurement of glossiness, and (ii) adhesion test were performed. Through this, the effect on the glossiness of nickel plating according to the glossiness of the undercoating and the difference in adhesion according to the surface roughness were confirmed.

(i) Visual inspection and glossiness measurement

10 is a photograph showing the appearance of plated articles that were plated with nickel by post-plating after plated with copper cyanide according to the present invention, and Table 9 below shows the measured values of glossiness of each plated article.

Glossiness of copper plating layer
(GU) Glossiness of Nickel Plated Layer
(GU) gloss deviation
(GU) high current density region low current density area Comparative Example 1 2.6 438 - - Comparative Example 6 104 514 369 145 Example 11 68 511 445 66

As a result of the experiment, Comparative Example 1 did not add a brightener or additive, and the glossiness of the bright nickel plating layer was 438GU. In Comparative Example 6, a gloss agent manufactured by JCU of Japan was added, and the glossiness of the glossy nickel plating layer was 514GU in the high current density area and 36GU in the low current density area, so the gloss deviation was 145GU. Finally, in Example 11, the semi-gloss additive of the present invention was added, and the glossiness of the glossy nickel plating layer was 511GU in the high current density region, 445GU in the low current density region, and the gloss deviation was 66GU. It can be seen that the glossiness of the nickel plated layer is significantly lower even with the same plating thickness when bright nickel plating is performed after copper cyanide plating without the use of copper. In addition, it can be confirmed that the nickel plating gloss between the two products shows similar gloss within the error range when the conventional high-gloss copper cyanide polish and the one-component semi-gloss additive of the present invention are used.

Through this, it can be confirmed that the adhesion with the post plating layer is improved and the glossiness of the nickel plating layer is increased due to the low surface roughness (fine etching surface) of the one-component additive. That is, it can be seen that even if the glossiness of the copper bronze plating layer is lower than that of the existing products, there is no significant difference in the glossiness during nickel plating due to the glossiness of a certain amount or more and the polishing effect of the surface.

In addition, looking at the gloss deviation of Comparative Examples 6 and 11, when using the semi-glossy additive of the present invention, the gloss deviation between the high current density area and the low current density area was significantly higher than when using the conventional Japanese JCU's gloss agent. decrease can be seen.

(ii) adhesion test

Previously, a test for confirming the adhesion strength of the plating layer of the copper cyanide plating-nickel plating prepared in Comparative Examples 6 and 11 was performed.

The adhesion test was confirmed by drawing a grid pattern on the surface of the specimen after plating, attaching the tape to the surface, leaving it for about 20 minutes, and then quickly removing the tape.

In the plated article of Example 11 of the present application, no lifting or tearing of the coating occurred, but in the plated article of Comparative Example 6, lifting or tearing occurred in a portion.

The present invention described above is not limited by the above-described embodiments and the accompanying drawings, and it is a technical field to which the present invention pertains that various substitutions, modifications and changes are possible without departing from the technical matters of the present invention. It will be clear to those of ordinary skill in the art. Therefore, the scope of the present invention is expressed by the following claims, and all changes or modifications derived from the meaning, scope, and equivalent concept of the claims should be construed as being included in the scope of the present invention.

10: multi-layer plating
100: plated material
200: blue copper plating layer
300: after plating layer

Claims (19)

copper cyanide compounds; and
Semi-glossy additives include;
The copper cyanide compound includes copper cyanide (CuCN), sodium cyanide (Na ₂ Cu(CN) ₃ ), potassium cyanide (K ₂ Cu(CN) ₃ ) or a mixture thereof,
The semi-gloss additive is
3-Hexane-2,5-diol (3-Hexyne-2,5-diol) compound; and
a sulfur compound; and
The sulfur compound comprises at least one of sodium saccharin (Sodium saccharin), sodium vinyl sulfonate (Sodium vinyl sulfonate) and sodium allyl sulfonate (Sodium allyl sulfonate),
Tsinghua copper plating solution. delete delete delete delete delete delete According to claim 1,
The semi-gloss additive is a copper cyanide plating solution further comprising N-polyether (N-Polyether) and L-polyether (L-Polyether). delete According to claim 1,
The semi-glossy additive further comprises at least one of butynediol ethoxylate, 2-butyne-1,4-diol, and glycine. delete According to claim 1,
The semi-gloss additive further comprises a surfactant,
The surfactant is a copper cyanide plating solution containing a fluorinated surfactant. 13. The method of claim 12,
The fluorine-based surfactant is a copper cyanide plating solution containing a potassium perfluorobutane sulfonate (Potassium perfluorobutane sulfonate) compound. delete According to claim 1,
A copper cyanide plating solution further comprising at least one of organic acid salts and inorganic acid salts. 16. The method of claim 15,
The organic acid salt is sodium potassium tartrate (Potassium sodium tartrate), sodium carbonate (Sodium carbonate) and potassium carbonate (Potassium carbonate) at least one of copper bronze plating solution. 16. The method of claim 15,
The inorganic acid salt is a copper cyanide plating solution comprising at least one of sodium hydroxide and potassium hydroxide. preparation of the material to be plated;
Preparation of copper cheonghwa plating solution; and
Containing; including;
The copper cyanide plating solution is the copper cyanide plating solution of any one of claims 1, 8, 10, 12, 13, and 15 to 17,
Bronze copper plating method. delete

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