KR20240053682A - Plating process for antenna injection molding - Google Patents

Abstract

The present invention relates to a plating process for a radar antenna injection molding. The plating process for an antenna injection molding according to the present invention comprises: a surface treatment process for performing surface treatment of an injection molding using plastic; an electroless metal plating process for performing electroless metal plating of the injection molding on which surface treatment has been completed; and an electrolytic metal plating process for performing electrolytic metal plating of an electroless metal-plated injection molding. The surface treatment process comprises: an alkaline degreasing process for removing a grease component attached to the surface of the injection molding by immersing the injection molding in an alkaline solution; an alkaline etching process for etching the surface of the injection molding through a chemical reaction using an alkaline etching solution; a glass etching process for removing a glass component existing on the surface of the injection molding; and an ultrasonic cleaning process for cleaning the surface of the injection molding using ultrasonic waves.

Description

Plating method for antenna injection molding {Plating process for antenna injection molding}

The present invention relates to a radar antenna, and more specifically, to a plating method for an injection-molded antenna case.

Radar antennas are increasingly being used to transmit and receive signals for detecting objects around vehicles. A radar antenna radiates radio waves and makes it possible to determine the presence or absence of an object, its distance, direction of movement, speed of movement, identification, classification, etc. by reflected waves or scattered waves produced when radio waves hit an object.

Recently, technologies for expanding the detection range and improving performance of these radar antennas are being studied to improve the collision avoidance radar of autonomous vehicles in preparation for the era of unmanned vehicles.

Radar antennas used recently are manufactured by injecting a case that forms the body of the antenna out of plastic, and plating a conductor with excellent reception and transmission of radio waves on the surface of the injected case. In this case, engineering plastic with excellent heat resistance and strength is used as the plastic material forming the antenna case.

However, the engineering plastics used to manufacture existing antenna cases are very limited in the types of plastics that can be plated. In other words, existing injection molded antenna cases are mainly manufactured using only specific types of plastic materials that can be etched and plated, such as ABS (Acrylonitrile Butadiene Styrene) resin, which reduces diversity in antenna product implementation and increases manufacturing costs. There was this.

Korean Patent Registration No. 10-2354520 (2022.01.18)

The technical problem to be solved by the present invention is to use specific engineering plastic materials such as polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT), which have excellent mechanical properties and have a small variation in shrinkage rate of the material itself. The object is to provide a plating method for an injection-molded antenna product that can easily plate the surface of the injection-molded antenna product at low cost.

A plating method for an injection-molded antenna product according to the present invention to solve the above-described technical problem includes a surface treatment process of performing surface treatment on the injection-molded product using plastic; An electroless metal plating process that performs electroless metal plating on an injection molded product whose surface treatment has been completed; An electrolytic metal plating process of performing electrolytic metal plating on an electroless metal-plated injection molded product, wherein the surface treatment process includes an alkaline degreasing process of removing fat and oil components attached to the surface of the injection molded product by immersing the injection molded product in an alkaline solution; An alkaline etching process that etches the surface of the injection molded product through a chemical reaction using an alkaline etching solution, a glass etching process that removes glass components present on the surface of the injection molded product, and ultrasonic cleaning that uses ultrasonic waves to clean the surface of the injection molded product. It is characterized by including a process.

Here, the plastic used in injection molding may be polycarbonate (PC)-based amorphous engineering plastic, or liquid crystal polymer (LCP) or polybutylene terephthalate (PBT)-based crystalline engineering plastic.

In the alkaline degreasing process, the extruded product can be degreased by immersing it in an alkaline degreasing solution with a concentration of 10% (v/v) at a temperature of 50° C. for 5 minutes and washed with water.

Additionally, in the alkaline etching process, the degreased extruded product may be etched by immersing it in an etching solution containing 300 g/L of KOH and 50 ml/L of AD70B(S) at a temperature of 65°C for 5 to 10 minutes, followed by water washing.

In addition, in the glass etching process, the etched injection molded product can be glass etched by immersing it in EC-LS(G) stock solution at 50° C. for 10 minutes and then washed with water.

In this case, a swelling process for swelling the surface of the alkaline degreased injection molded product may be further included between the alkaline degreasing process and the glass etching process.

At this time, in the swelling process, the surface of the injection molded product can be swollen at a temperature of 43°C for 5 to 10 minutes using DMF stock solution.

In addition, in the step before the swelling process, a hot air drying process may be additionally performed in which the injection molded product that has undergone the alkaline degreasing process is dried with hot air at a temperature of 60° C. for 10 minutes.

In the ultrasonic cleaning process, the injection molded product on which glass etching has been completed can be cleaned by immersing it in cleaning water at a temperature of 40°C and then applying ultrasonic waves for 5 minutes.

Meanwhile, the electroless metal plating process includes a conditioning process of cleaning the surface of the injection molded product after ultrasonic cleaning with a conditioner, a first pre-dip process of primarily removing contaminants attached to the surface of the injection molded product, and palladium ( A palladium catalyst treatment process that imparts conductivity to the surface of the injection-molded product through a reduction reaction with a catalyst containing pd), an activation process of activating the surface of the injection-molded product by immersing the injection-molded product in an activation treatment liquid, and removing contaminants attached to the surface of the injection-molded product. It may include a second pre-dip process for secondary removal and an electroless copper plating process for forming a metal film in an electroless manner on the surface of the injection molded product.

Here, in the conditioning process, the injection molded product that has completed ultrasonic cleaning can be immersed in a KIAC-C surfactant solution with a concentration of 20% (v/v), washed at 50°C for 5 minutes, and then rinsed with water.

In addition, in the first pre-dip process, contaminants attached to the surface of the injection product can be removed by immersing the injection product in an HCl solution with a concentration of 10% (v/v) for 2 minutes at a temperature of 25 ° C.

In addition, in the palladium catalyst treatment process, the injection product that has completed the first pre-dip treatment can be immersed in a mixed solution of 150 ml / L of HCl and 50 ml / L of CNI-S at a temperature of 35 ° C. for 5 minutes and then washed with water. .

In addition, in the activation process, the injection molded product on which palladium catalyst treatment has been completed can be immersed in a 10% (v/v) concentration H2SO4 solution at 40°C for 3 minutes and then washed with water.

In addition, in the second pre-dip process, contaminants on the surface of the injection pool can be removed by immersing the activated injection molded product in a 5% (v/v) formalin solution at a temperature of 25°C for 2 minutes.

In the electroless copper plating process, the injection molded product for which the second pre-dip process has been completed is mixed with a solution of 80 ml/L ECP-80M and 40 ml/L ECP-80M, or 9 ml/L NaOH and 8.8 ml/L formalin. Copper (Cu) plating can be done by immersing in the mixed solution at 43°C for 60 to 100 minutes and then washing with water.

Meanwhile, the electrolytic metal plating process includes an electrolytic Ag-St plating process of forming an Ag-St metal film on the surface of the injection molded product by applying a current between the anode and the cathode, and forming an Ag metal film on the surface of the injection molded product with the Ag-St metal film formed. It includes an electrolytic Ag plating process to form an electrolytic Ag plating process, a discoloration prevention process in which the surface of the injection molded product on which the Ag metal film is formed is treated to prevent discoloration using a discoloration prevention agent, and a hot air drying process in which the surface of the injection molded product that has been treated to prevent discoloration is dried using hot air. can do.

Here, in the electrolytic Ag-St plating process, the injection molded product on which electroless copper plating was completed is immersed in a mixed solution of 3.1 g/L AgCN and 110 g/L KCN at a temperature of 25°C for 0.5 minutes and electrolyzed by applying a 3V voltage. It can be silver-plated and washed.

In the electrolytic Ag plating process, the injection molded product on which electrolytic Ag-St plating was completed was immersed in a mixed solution of 37.5 g/L AgCN and 80 g/L KCN at a temperature of 25°C for 5 to 15 minutes and 0.5 A/d㎡. It can be subjected to electrolytic silver plating by applying current and then washed with water.

In addition, in the discoloration prevention process, the electrolytic silver-plated injection molded product can be immersed in a solution containing a 0.5% (v/v) concentration of an anti-discoloration agent at a temperature of 55° C. for 1 minute and then washed with water.

Additionally, in the hot air drying process, the electrolytic silver-plated injection molded product can be dried using hot air at 60°C for 10 minutes.

According to the antenna injection plating method of the present invention described above, engineering plastic materials such as polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT), which were previously impossible to perform etching and plating operations due to the characteristics of the materials, can be used. By applying this method to manufacture an antenna injection molded product and making it possible to perform etching and plating on the surface of the manufactured antenna injection molded product, it is possible to expand the diversity in the use of plastic materials for manufacturing antenna injection molded products.

In addition, the present invention allows the antenna case to be manufactured using specific plastic materials with low X/Y axis shrinkage variation, such as polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT). It is possible to secure advantageous dimension control during injection molding of the antenna case, and when assembling the injected antenna case, assembly tolerances do not occur, preventing leakage of radio waves and improving product reliability.

In addition, the present invention injects an antenna case using polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT), materials that previously could not be etched and plated, and etching and plating the surface of the injected antenna case. By being able to implement it perfectly, the external design of the radar antenna can be realized more diversely by using a wider variety of engineering plastics, and the electrical uniformity of the copper (Cu)/silver (Ag) plating layer is increased. The electrical stability of the plating layer can be improved. In addition, since the plating boundary is clear and uniform, the radiation efficiency of radio waves can be maximized, which has the advantage of greatly improving the quality of antenna products.

In addition, when plating the surface of an antenna extruded from polycarbonate (PC), it is possible to etch the surface of the extruded product without adding the swelling process, which is the most important process among the etching processes for the surface of the extruded product. By simplifying, the plating time can be shortened, which has the advantage of reducing manufacturing costs.

In addition, copper and silver plating is performed on the surface of the antenna injection molded from engineering plastics such as polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT) using electroless and electrolytic plating methods. You can achieve the effect of decorating the external surface of the antenna product with a glossy or matte finish. Antenna products plated using this plating method have superior surface strength compared to existing products, and mechanical properties such as abrasion resistance and heat resistance are improved, improving the product surface. There is an advantage that the quality of the product is improved.

Figures 1 and 2 are perspective views showing the structure of an injection-molded case of a radar antenna to which the present invention is applied.
Figure 3 is an exemplary diagram showing an example of an engineering plastic material that can be selected as a material for an injection-molded antenna case in the present invention.
Figures 4 and 5 are process charts and flow charts showing the plating process of the radar antenna injection molded product according to the first embodiment of the present invention.
Figures 6 and 7 are process charts and flow charts showing the plating process of the injection-molded radar antenna according to the second embodiment of the present invention.
Figure 8 is an actual photograph of an antenna case plated with copper and silver using the antenna injection plating method of the present invention.

Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention.

However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In addition, it should be noted that parts indicated with the same reference numbers throughout the detailed description refer to the same components.

First, Figures 1 and 2 show the case structure constituting the body of the radar antenna 300 according to the present invention.

Here, in the drawing, the direction in which the first case 100 of the radar antenna is located is the front direction, and the direction in which the second case 200 is located is the rear direction.

Referring to Figures 1 and 2, the radar antenna 300 according to the present invention includes a substrate (not shown) for transmitting and receiving electromagnetic waves, and a case that is combined with the substrate to form a path for electromagnetic waves to move in the internal space. do.

The case includes a first case 100 and a second case 200 having a rectangular external structure. The first case 100 and the second case 200 are injection molded from an engineering plastic resin material.

The first case 100 and the second case 200 are combined with each other to form one case body, and the case body is combined with a substrate to form the radar antenna 300. And, a waveguide that serves to transmit electromagnetic waves is formed in the internal space formed by combining the first case 100 and the second case 200.

The first case 100 has a plurality of slots 121 formed in the center through which electromagnetic waves are radiated to the outside or incident, and the first case 100 and the second case 200 are assembled around the plurality of slots 121. During work, a plurality of alignment holes 104 are formed into which alignment pins (not shown) of an alignment jig can be inserted.

A first contact portion 110 that is bonded to the second case 200 through an adhesive is formed in a certain area of the back of the first case 100. The first contact portions 110 are arranged in pairs on both long sides of the first case 100 to form a mutually symmetrical structure.

A slot portion 120 composed of a plurality of slots 121 is disposed at the rear center of the first case 100. The slot unit 120 emits or injects electromagnetic waves to the outside through a plurality of slots 121.

At this time, the plurality of slots 121 may be configured as reception ports or transmission ports. That is, the plurality of slots 121 may be configured as a transmission port connected to a transmission terminal of a board (not shown), or may be configured as a reception port connected to a reception terminal of the board.

The first case 100 includes a plurality of engaging protrusions 130 protruding from the rear in the direction of the second case 200 and a partition wall 140 formed with a wall structure surrounding the slot portion 120.

The partition wall 140 has a structure that protrudes from the rear of the first case 100 toward the second case 200 and partitions the inside and outside of the slot portion 120. The partition wall 140 forms a part of the waveguide surrounding the slot portion 120 together with the contact surface 220 formed on the second case 200. That is, the partition wall 140 forms a waveguide, which is a movement path of electromagnetic waves communicating with a plurality of slots 121 in the internal space located between the first contact portions 110 on both sides of the first case 100.

The second case 200 is joined to the first case 100 at the rear side of the first case 100. The second case 200 is formed on the front side with a pair of second contact parts 210 that are bonded to the first contact part 110 of the first case 100 through an adhesive, and the second contact part 210 portion A plurality of coupling grooves 230 that can be coupled to the plurality of coupling protrusions 130 formed on the first case 100 are formed.

And, a plurality of alignment holes 204 corresponding to the plurality of alignment holes 104 of the first case 100 are formed in the second case 200. In addition, the front side of the second case 200 is in close contact with the partition wall 140 formed in the first case 100, and a waveguide, which is a movement path of electromagnetic waves, is located in the internal space between the first case 100 and the second case 200. A close contact surface 220 constituting a part of is formed.

The contact surface 220 has a flat surface with a smooth surface, and is in close contact with the partition wall 140 of the first case 100 when the first case 100 and the second case 200 are assembled. Accordingly, a waveguide is formed in the internal space formed by the combination of the first case 100 and the second case 200, which is a space in which electromagnetic waves move, which is formed when the partition wall 140 and the contact surface 220 come into contact.

A port 240 is formed in one area of the contact surface 220 of the second case 200 in a structure that vertically penetrates the second case 200 to communicate with the internal waveguide. Electromagnetic waves flowing into the port 240 may move along the internal waveguide and be radiated to the outside through the plurality of slots 121.

This port 240 may be configured as a transmission port that transmits electromagnetic waves into the waveguide, or a reception port that receives electromagnetic waves input from the outside through the waveguide. That is, the port 240 may be configured as a transmitting port connected to a transmitting terminal of a board (not shown) coupled to the rear of the second case 200, or may be configured as a receiving port connected to a receiving terminal of the board.

The board transmits electromagnetic waves to the outside through a waveguide formed in the space inside the case, and receives electromagnetic waves received through a waveguide inside the case to process the electromagnetic waves as signals. The unexplained symbol 206 is a fastening hole for fastening a substrate to the rear of the second case 200.

The radar antenna 300 configured in this way can be manufactured through several processes as follows. That is, the radar antenna 300 can be manufactured by sequentially performing a case injection process, a plating process, a curing process, and a case assembly process.

In the case injection process, the case is injected with engineering plastic and then cooled to produce the case (100, 200). Here, polycarbonate (PC) and liquid crystal polymer (LCP) materials can be used as the injection material for the case, which have a small difference in shrinkage rate in the X/Y axis directions and allow easy dimensional control during case injection.

In the plating process, a shielding layer can be formed by plating metal on the surfaces of the first case 100 and the second case 200 manufactured through an injection process. Here, in the plating process, one metal of tin (Sn), nickel (Ni), copper (Cu), gold (Au), and silver (Ag) or a mixed metal of two or more are plated to form the first case 100. And a shielding layer may be formed on the surface of the second case 200.

The first case 100 and the second case 200 for which the plating process has been completed may be hardened by performing a separate hardening process. In the curing process, the first case 100 and the second case 200 may be hardened through one of a pressing process and a heat aging process.

In the case assembly process, the radar antenna 300 can be manufactured by assembling the first case 100 and the second case 200 for which the curing process has been completed. In this case, in the case assembly process, the first case 100 and the second case 200 are aligned using an alignment jig, and the first case 100 is pressed and joined to the adhesive-applied second case 200. It can be assembled in this way.

At this time, thermosetting epoxy resin may be used as the adhesive applied between the contact portions 110 and 210 on both sides of the first case 100 and the second case 200, and both cases 100 and 200 are bonded with an epoxy adhesive. Afterwards, in order to shorten the curing time, an ultrasonic heat curing process in which ultrasonic energy is applied to the epoxy adhesive part to heat harden it can be performed in parallel.

On the other hand, radar antennas have the advantage of being able to be mass-produced in a short period of time and manufactured at low cost because the case that makes up the body is injection molded with engineering plastic material. However, shrinkage and deformation occur during the injection process of the case, so the injection molded product The disadvantage is that the dimensions are irregular, which reduces dimensional accuracy and makes precise dimensional control difficult.

If a molding error occurs in a case made of injection molded plastic, assembly errors may occur even when the case parts are assembled, and there is a risk that the radar antenna may have antenna performance that is different from the initially designed specifications. Therefore, when selecting a case material for manufacturing a radar antenna, it is most important to select a plastic resin that causes less shrinkage and deformation during the case injection process.

For example, in the case of polycarbonate (PC), a resin made by polymerizing carbonate, it is as hard as metal and resistant to acids and heat well, so it is often used instead of metal to manufacture various mechanical and electrical parts, but due to the nature of the material, the surface It is impossible to etch or directly plate. For this reason, the method of plating the surface using the double injection method has been used in the past, but this double injection method requires a large number of molds, which acts as a factor in increasing the production cost, and the work process is very complicated, making the work difficult. This causes problems that reduce efficiency and productivity. In addition, the surface of the manufactured antenna component cannot be perfectly plated to even the finest details, which increases the defect rate of the product and causes a problem in which signal transmission/reception sensitivity is reduced.

In addition, the existing plating method applied to the antenna injection molded product cannot be applied to radar antennas, etc., where the electrical stability of the plated surface must be guaranteed due to the deterioration of the electrical uniformity of the plated surface, and the existing plating process alone is used to reduce the electrical uniformity of the plated surface. There were many problems, such as the radiation efficiency and overall performance of the radar antenna being reduced due to non-uniformity and uncertainty, thereby reducing the reliability of product quality.

Accordingly, in the present invention, when metal plating an antenna case injection molded product containing a certain level or more of a specific resin material such as polycarbonate (PC) or liquid crystal polymer (LCP), the adhesion of the metal plating to these antenna injection molded products is improved, We aim to provide a plating method to improve the surface properties of products by using both electroless plating and electrolytic plating methods.

Figure 3 shows an example of an engineering plastic material that can be selected as a case material for the radar antenna when manufacturing the radar antenna of the present invention.

As mentioned earlier, there are various types of engineering plastics that can be used as materials for antenna cases, but due to the characteristics of plastic materials, the types of engineering plastics that can be etched and plated are very limited. Therefore, in the present invention, several engineering plastic materials were selected that allow easy dimension control during injection molding of the antenna case and facilitate surface etching and plating of the molded case.

That is, in the present invention, as shown in the table of FIG. 3, polycarbonate (PC) and liquid crystal polymer (LCP), which are materials that have a small deviation in shrinkage rate in the X/Y axis direction and are easy to control dimensions during injection, are used. ), polybutylene terephthalate (PBT), and polyethylene terephthalate (PET) were selected as injection molding materials for the antenna case. However, while these materials have a small variation in shrinkage rate, making it easy to control dimensions, there is a disadvantage in that surface etching and plating are not possible due to the nature of the materials. Therefore, the present invention attempted to solve this problem through a specific plating method for antenna injection moldings, which will be described later.

Hereinafter, as an example of the plating method of an injection-molded antenna product according to the present invention, a method of plating an injection-molded antenna case made of polycarbonate (PC) and liquid crystal polymer (LCP) material will be described in detail.

Figures 4 and 5 show the plating process of the radar antenna case according to the first embodiment of the present invention, and the antenna case is injection molded with a resin containing polycarbonate (PC), a type of amorphous engineering plastic. It shows the entire plating process (hereinafter referred to as ‘injection molded product’).

Referring to Figures 4 and 5, the plating process of the antenna injection molded product according to the first embodiment of the present invention is first, a surface pretreatment process for the antenna case injection molded product (S10) with polycarbonate (PC) resin. A surface treatment process (S20) that performs treatment, an electroless metal plating process (S30) that performs electroless metal plating of the surface-treated injection molded product, and an electrolytic metal plating process that performs electrolytic metal plating of the electroless metal plated injection molded product. Includes process (S40).

Here, the surface treatment process (S20) of the antenna injection molded product includes the alkaline degreasing process (S21) of removing the oily components attached to the surface of the injection molded product by immersing the molded product in an alkaline solution, and the surface of the injection molded product through a chemical reaction using an alkaline etching solution. It includes an alkaline etching process (S22) for etching, a glass etching process (S23) for removing glass components present on the surface of the injection molded product, and an ultrasonic cleaning process (S24) for cleaning the surface of the injection molded product using ultrasonic waves. do.

In the first step, the alkaline degreasing process (S21), the injection molded product (case) made of polycarbonate (PC) resin is soaked in an alkaline degreasing solution (product name 'CLEAN 500') with a concentration of 10% (volume/volume) at a temperature of 50°C for 5 minutes. Remove foreign substances such as dust or oil adsorbed on the surface of the injection molded product by immersing it for several minutes, and wash the injection molded product with complete removal of foreign substances twice in succession (S21-1, S21-2).

Next, in the alkaline etching process (S22), the injection molded product degreased in the alkaline degreasing process (S21) is placed in an alkaline etching solution containing 300 g/L of KOH and 50 ml/L of AD70B(S) at a temperature of 65°C for 5 to 10 minutes. It is etched by immersion for a while, and washed twice in succession to remove the alkaline etching solution attached to the surface of the injection molded product after the etching process has been completed (S22-1, S22-2).

In this alkaline etching process (S22), micropores are formed on the surface of the injection-molded product, thereby ensuring strong adhesion of the plated metal during the subsequent metal plating process on the surface of the injection-molded product.

In the glass etching process (S23), the injection molded product etched through the alkaline etching process (S22) is etched by immersing it in EC-LS(G) stock solution at 50°C for 10 minutes and washed twice in succession. .(S23-1,S23-2)

Next, in the ultrasonic cleaning process (S24), the injection molded product on which the glass etching work has been completed is immersed in cleaning water at a temperature of 40° C., and then ultrasonic waves are applied for 5 minutes to clean the surface of the injection molded product.

In this ultrasonic cleaning process (S24), the etching liquid on the surface of the injection molded product during the previous etching process is removed using the cavitation effect of ultrasonic waves, thereby completely cleaning the surface of the injection molded product.

When all of the above surface treatment processes (S20) for the surface of the injection molded product are completed, an electroless metal plating process (S30) in which metal is plated through a chemical reaction on the surface of the injection molded product is performed.

The electroless metal plating process (S30) includes a conditioning process (S31), a first pre-dip process (S32), a palladium (pd) catalyst treatment process (S33), an activation process (S34), and a second pre-dip process (S35). , electroless copper plating process (S36), and these processes are performed sequentially.

In the conditioning process (S31), which is the first step of the electroless metal plating process (S30), the surface of the injection molded product for which the ultrasonic cleaning operation in the previous step has been completed is cleaned with a conditioner containing a cationic surfactant.

In this case, in the conditioning process (S31), the injection molded product that has completed ultrasonic cleaning is immersed in a KIAC-C surfactant solution with a concentration of 20% (v/v), washed at 50°C for 5 minutes, and then washed twice in succession. .(S31-1,S31-2)

Next, in the first pre-dip process (S32), contaminants attached to the surface of the injection molded product that has been cleaned are primarily removed using a conditioner.

At this time, in the first pre-dip process (S32), the injection product that has been cleaned through the conditioning process (S31) is immersed in an HCl solution with a concentration of 10% (v/v) for 2 minutes at a temperature of 25°C to remove contaminants attached to the surface of the injection product. is primarily removed.

In this first pre-dip process (S32), the palladium ion catalyst functions to provide cations so that it reacts well with the surface of the injection product in the next process, the palladium catalyst treatment process (S33).

Next, in the palladium catalyst treatment process (S33), conductivity is imparted to the surface of the injection product through a reduction reaction using a catalyst containing palladium (pd).

In this palladium treatment process (S33), palladium (Pd) metal is deposited on the surface of the injection molded product to strengthen the adhesion of the copper plating to the surface of the injection molded product during future copper (Cu) plating.

At this time, in the palladium catalyst treatment process (S33), the extruded product that went through the first pre-dip process (S32) was immersed in a mixed solution of 150 ml/L HCl and 50 ml/L CNI-S at a temperature of 35°C for 5 minutes. Wash twice in a row. (S33-1, S33-2)

Next, in the activation process (S34), the palladium catalyst applied to the surface of the injection molded product is activated by immersing the injection molded product in an activation treatment liquid. That is, in the activation process (S34), the palladium (Pd) applied to the surface of the injection molded product is activated through the palladium catalyst treatment process (S33), thereby strengthening the conductivity and affinity of the electroless copper (Cu) plating to be performed later.

In this activation process (S34), the extruded product treated with a palladium catalyst through the palladium catalyst treatment process (S33) is immersed in a 10% (v/v) concentration of H2SO4 solution at 40°C for 3 minutes, then taken out, and activated twice in succession. Wash with water. (S34-1, S34-2)

In the second pre-dip process (S35), the injection product activated through the activation process (S34) is immersed in a formalin solution with a concentration of 5% (v/v) for 2 minutes at 25°C to remove contaminants attached to the surface of the injection product. remove it gradually.

Next, in the electroless copper plating process (S36), a copper (Cu) metal film is formed on the surface of the injection molded product using an electroless method. That is, in the electroless copper plating process (S36), copper (Cu) is precipitated through a chemical reaction on the surface of the injection molded product that has undergone the second pre-dip process (S35) and the surface of the injection molded product is plated with copper. This process is performed to enable electrolytic plating by creating a conductive film through copper plating on the surface of the injection molded product.

In this case, in the electroless copper plating process (S36), the injection molded product for which the second pre-dip process (S35) has been completed is mixed with 80 ml/L of ECP-80M and 40 ml/L of ECP-80M, or 9 ml/L of NaOH. Copper (Cu) is plated on the surface of the extruded product by immersing it in a mixture of formalin and 8.8 ml/L at a temperature of 43°C for 60 to 100 minutes, and then washed twice in succession (S36-1, S36-2).

In this electroless copper plating process (S36), copper (Cu) metal is deposited on the surface of the injection molded product through a chemical reaction, thereby strengthening the conductivity of the surface of the copper-plated injection molded product and providing an electromagnetic wave shielding function. In this case, the average thickness of copper plating on the surface of the injection molded product can be set to 5.5㎛.

Meanwhile, the injection molded product that has completed the electroless metal plating process (S30) as described above is input into the electrolytic metal plating line, and electrolytic metal plating is performed on the surface of the injection molded product.

The electrolytic metal plating process (S40) includes an electrolytic Ag-St plating process (S41), an electrolytic Ag plating process (S42), an anti-discoloration process (S43), and a hot air drying process (S44), and these processes are common facilities. It is performed sequentially in an electrolytic metal plating line.

In the electrolytic Ag-St plating process (S41), a current is applied between the anode and cathode in an electrolytic cell to form an Ag-St metal film on the surface of the copper-plated injection molded product.

At this time, in the electrolytic Ag-St plating process (S41), the copper-plated injection molded product is immersed in a mixed solution of 3.1 g/L of AgCN and 110 g/L of KCN at a temperature of 25°C for 0.5 minutes, and a 3V voltage is applied to the surface of the injection molded product. After forming the Ag-St metal film, it is washed twice in succession (S41-1, S41-2).

Next, in the electrolytic Ag plating process (S42), a silver (Ag) metal film is formed on the surface of the injection molded product on which the Ag-St metal film is formed.

In this case, in the electrolytic Ag plating process (S42), the Ag-St plated injection molded product is immersed in a mixed solution of 37.5 g/L of AgCN and 80 g/L of KCN at a temperature of 25°C for 5 to 15 minutes and applied at 0.5 A/d. ㎡ is treated with silver (Ag) plating by applying current, and washed twice in succession (S42-1, S42-2). In this case, the average thickness of silver (Ag) plating on the surface of the injection molded product is 2.5㎛. can be set.

Next, in the discoloration prevention process (S43), the surface of the silver (Ag) plated injection molded product is treated to prevent discoloration using a discoloration prevention agent.

In this discoloration prevention process (S43), the silver (Ag) plated injection molded product is immersed in a solution containing a 0.5% (v/v) concentration of an anti-discoloration agent (ANTIS-1000) at a temperature of 55°C for 1 minute and then washed twice. Wash continuously. (S43-1, S43-2)

The plating surface of the injection molded product treated to prevent discoloration through this discoloration prevention process (S43) does not cause stains or changes in color tone.

Lastly, in the hot air drying process (S44), the plating surface of the injection molded product that has been treated to prevent discoloration is dried using hot air.

In this case, in the hot air drying process (S44), the electrolytic silver (Ag) plated injection molded product is dried using hot air at 60° C. for 10 minutes to completely remove moisture from the silver plated injection molded product.

By plating the antenna injection molded product through the above series of continuous processes, etching and copper/silver plating work can be done on the surface of the polycarbonate (PC) injection molded product, which was previously impossible to do due to material characteristics. It can happen.

In this way, as etching and plating on the surface of the antenna extruded from polycarbonate (PC) become possible, the electrical stability of the plating layer can be improved by increasing the electrical uniformity of the copper (Cu)/silver (Ag) plating layer, As the plating interface is formed clearly and uniformly, the radiation efficiency of radio waves can be maximized and product quality can be improved.

In addition, in the manufacture of antenna injection molded products, it is possible to manufacture antenna parts using polycarbonate (PC) material with a small deviation in By reducing the occurrence of tolerances, leakage of radio waves can be prevented and the reliability of the product can be improved.

In addition, during the surface treatment process of the antenna injection molded product made of polycarbonate (PC), the entire plating process can be performed because the surface of the injection molded product can be etched without separately performing the swelling process, which is the most important process in the etching process. By reducing the size, the plating time can be shortened, which has the advantage of reducing the manufacturing cost of the antenna injection molded product.

Meanwhile, Figures 6 and 7 show a plating method of an injection-molded antenna product according to a second embodiment of the present invention, which shows the entire plating of an injection-molded antenna product made of an engineering plastic material containing liquid crystal polymer (LCP). It shows the process.

Referring to Figures 6 and 7, the plating method of the antenna case according to the second embodiment of the present invention involves surface treatment, which is a preliminary treatment process for the antenna case injection molded product (S50) with liquid crystal polymer (LCP) resin. A surface treatment process (S60) that performs, an electroless metal plating process (S70) that performs electroless metal plating of the surface-treated injection molded product, and an electrolytic metal plating process that performs electrolytic metal plating of the electroless metal plated injection molded product. Includes (S80).

Here, the surface treatment process (S60) of the antenna injection molded product includes an alkaline degreasing process (S61) of removing the oily components attached to the surface of the injection molded product by immersing the injection molded product in an alkaline solution, and swelling the surface of the injection molded product that has been treated with alkaline degreasing. ) a swelling process (S62), an alkaline etching process (S63) that etches the surface of the injection molded product through a chemical reaction using an alkaline etching solution, and a glass etching process that removes glass components present on the surface of the injection molded product. (S64) and an ultrasonic cleaning process (S65) that cleans the surface of the injection molded product using ultrasonic waves.

In the alkaline degreasing process (S61), the injection molded product made of liquid crystal polymer (LCP) resin is immersed in an alkaline degreasing solution (product name 'CLEAN 500') with a concentration of 10% (volume/volume) for 5 minutes at a temperature of 50℃ to degrease the surface of the injection molded product. Remove foreign substances such as dust or oil adsorbed on the product, and wash the injection molded product from which foreign substances have been removed twice in succession (S61-1, S61-2).

In the swelling process (S62), the surface of the injection molded product degreased with an alkaline grease is treated with swelling.

In this swelling process (S62), the antenna injection molded product is immersed in a swelling solution to swell the surface of the injection molded product as finely as desired, thereby smoothing the alkaline etching performed in the next process and facilitating the formation of a plating layer performed in the future.

At this time, in the swelling process (S62), the surface of the antenna injection molded product is immersed in DMF stock solution, which is a swelling solution, and the surface of the antenna molded product is swollen for 5 to 10 minutes at a temperature of 43°C, and then washed twice in succession. (S62-1 ,S62-2)

Here, in the step before performing the swelling process (S62), a hot air drying process (S61-3) is additionally performed in which the antenna injection molded product that has completed the alkaline degreasing process (S61) is dried with hot air at a temperature of 60° C. for 10 minutes. You can.

By evaporating the remaining moisture on the surface of the injection molded product through this hot air drying process (S61-3), it is possible to prevent the reactivity of the swelling solution from being reduced by moisture on the surface of the injection molded product in the swelling process (S62). there is.

In the alkaline etching process (S63), the injection molded product swollen in the swelling process (S62) is placed in an alkaline etching solution containing 300 g/L of KOH and 50 ml/L of AD70B(S) at a temperature of 65°C for 5 to 10 minutes. The surface of the injection molded product is etched by immersion, and after completion of the etching treatment, it is washed twice in succession to remove the alkaline etching solution attached to the surface of the injection molded product (S63-1, S63-2).

In the glass etching process (S64), the injection molded product etched through the alkaline etching process (S63) is glass etched by immersing it in EC-LS(G) stock solution at 50°C for 10 minutes and washed twice in succession. (S64) -1,S64-2)

In the ultrasonic cleaning process (S65), the injection molded product on which the glass etching process has been completed is immersed in cleaning water at a temperature of 40°C and then ultrasonic waves are applied for 5 minutes, thereby completely removing the etching liquid on the surface of the injection molded product during the etching process.

In Yiwu, where the surface treatment process (S60) for the surface of the injection-molded antenna has been completed, the electroless metal plating process (S70) is performed to plate metal through a chemical reaction on the surface of the injection-molded product.

The electroless metal plating process (S70) includes a conditioning process (S71), a first pre-dip process (S72), a palladium (pd) catalyst treatment process (S73), an activation process (S74), a second pre-dip process (S75), The electroless copper plating process (S76) is performed sequentially.

In the conditioning process (S71), the injection molded product that has been ultrasonic cleaned in the previous step is immersed in a KIAC-C surfactant solution with a concentration of 20% (v/v), washed at 50°C for 5 minutes, and then washed twice in succession. (S71-1,S71-2)

In the first pre-dip process (S72), the injection product that has been washed with a conditioner is immersed in a 10% (v/v) HCl solution at a temperature of 25°C for 2 minutes to primarily remove contaminants attached to the surface of the injection product, In the subsequent palladium catalyst treatment process (S73), the palladium ion catalyst functions to provide cations so that it reacts well with the surface of the injection product.

In the palladium catalyst treatment process (S73), palladium (Pd) metal is deposited on the surface of the extruded product through a reduction reaction using a catalyst containing palladium (pd) to strengthen adhesion during copper (Cu) plating.

In this palladium catalyst treatment process (S73), the extruded product that has undergone the first pre-dip process (S72) is immersed in a mixed solution of 150 ml/L of HCl and 50 ml/L of CNI-S at a temperature of 35°C for 5 minutes. Wash twice in a row. (S73-1, S73-2)

In the activation process (S74), palladium (Pd) applied to the surface of the injection molded product is activated to enhance conductivity and affinity during copper (Cu) plating. In this activation process (S74), the palladium catalyst-treated injection product is immersed in a 10% (v/v) H2SO4 solution at 40°C for 3 minutes, then taken out and washed twice in succession. (S74-1, S74) -2)

In the second pre-dip process (S75), the activated injection molded product is immersed in a formalin solution with a concentration of 5% (v/v) at 25°C for 2 minutes to secondarily remove contaminants attached to the surface of the molded product.

In the electroless copper plating process (S76), copper (Cu) is precipitated on the surface of the injection product through a chemical reaction and the surface of the injection product is plated with copper (Cu). In this case, the injection product that has gone through the second pre-dip process (S75) is mixed with a solution of 80 ml/L of ECP-80M and 40 ml/L of ECP-80M, or a mixture of 9 ml/L of NaOH and 8.8 ml/L of formalin. The surface of the injection molded product is plated with copper (Cu) by immersing it in the solution for 60 to 100 minutes at a temperature of 43°C, and then washed twice in succession (S76-1, S76-2).

When the electroless metal plating process (S70) is completed in this way, the antenna injection molded product is input into the electrolytic metal plating line to perform electrolytic metal plating on the surface of the injection molded product.

In the electrolytic metal plating process (S80), the electrolytic Ag-St plating process (S81), electrolytic Ag plating process (S82), anti-discoloration process (S83), and hot air drying process (S84) are sequentially performed in the electrolytic metal plating line, which is a common facility. It goes on.

In the electrolytic Ag-St plating process (S81), an Ag-St metal film is formed by applying current to the surface of the copper-plated injection molded product. In this case, the copper-plated injection molded product was immersed in a mixed solution of 3.1 g/L of AgCN and 110 g/L of KCN at a temperature of 25°C for 0.5 minutes, and a 3V voltage was applied to form an Ag-St metal film on the surface of the injection molded product. Then wash twice in a row. (S81-1, S81-2)

In the electrolytic Ag plating process (S82), a silver (Ag) metal film is formed on the surface of the injection molded product on which the Ag-St metal film is formed. In this case, the Ag-St plated injection molded product was immersed in a mixed solution of 37.5 g/L AgCN and 80 g/L KCN at a temperature of 25°C for 5 to 15 minutes, and a current of 0.5 A/dm2 was applied to silver ( Ag) plating and washing twice in succession (S82-1, S82-2)

In the discoloration prevention process (S83), the silver (Ag) plated injection molded product is treated to prevent discoloration by immersing it in a solution containing 0.5% (v/v) concentration of anti-discoloration agent (ANTIS-1000) at 55°C for 1 minute. Wash continuously. (S83-1, S83-2)

Finally, in the hot air drying process (S84), the anti-discoloration treated silver-plated injection molded product is dried using hot air at 60°C for 10 minutes, and the dried product is inspected.

In the second embodiment above, a method of plating an antenna injection molded product made of liquid crystal polymer (LCP) material was described. However, the method of plating an antenna molded product made of liquid crystal polymer (LCP) material was described. However, the method of plating an antenna molded product made of liquid crystal polymer (LCP) material was described. Etching and plating can be performed on the antenna injection-molded product through the same process as described above.

For reference, FIG. 8 is attached with an actual photograph of an antenna case plated with copper and silver through the plating method described in the above-described embodiments. Here, Figures 8 (a) and (b) show actual photographs and gain characteristics of copper (Cu) and silver (Ag) plated antenna cases, respectively.

By applying the plating method of the antenna injection molded product of the present invention described in the above-described embodiments, polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT), which were previously impossible to perform etching and plating work due to the characteristics of the materials, Since it is possible to manufacture antenna injection molded products by applying engineering plastic materials such as ), it is possible to expand the diversity in the use of engineering plastic materials when manufacturing radar antennas.

In particular, the present invention makes it possible to manufacture antennas using specific plastic materials with low X/Y axis shrinkage variation, such as polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT), thereby enabling dimensional control during injection molding. Advantages can be secured, and the molding error of the case injection molded product is reduced, thereby preventing leakage of radio waves by preventing gaps in the assembled antenna structure and improving the reliability of the product.

In addition, by using the plating method of the antenna injection molded product according to the present invention, the surface of the antenna component injected from polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT), which were previously impossible to etching and plating, can be improved. Since etching and complete plating can be performed, the external design of the radar antenna can be implemented in a wider variety of ways by using various types of engineering plastics, and the electrical uniformity of the copper (Cu)/silver (Ag) plating layer is improved. By increasing , the electrical stability of the plating layer can be improved.

In particular, when plating an antenna injection molded product using polycarbonate (PC), the surface of the plated object can be etched without adding the swelling process, which is the most important process among the surface etching processes of the injection molded product. By reducing the entire plating process, the plating time can be shortened, which has the advantage of reducing manufacturing costs.

In addition, a discoloration prevention process is performed by immersing the electrolytic silver (Ag) plated injection molded product in a 0.5% (v/v) ANTIS-1000 aqueous solution for 1 minute at 55°C and then washing it twice in succession, thereby reducing the copper (Cu)/silver It has the advantage of improving the reliability of copper (Cu)/silver (Ag) plated antenna products by preventing discoloration and corrosion, which have been pointed out as disadvantages of (Ag) plated products.

In addition, copper and silver plating is performed on the surface of injection-molded antenna products using engineering plastics such as polycarbonate (PC), liquid crystal polymer (LCP), and polybutylene terephthalate (PBT) using electroless and electrolytic plating methods. By doing so, it is possible to create the effect of decorating the external surface of the product with a glossy or matte finish, and antenna products plated using this plating method have superior surface strength and improved mechanical properties such as wear resistance and heat resistance compared to existing products. There is an advantage that the quality of the product surface is improved.

Although preferred embodiments of the present invention have been described above, the scope of the present invention is not limited to these specific embodiments, and those skilled in the art can make appropriate changes within the scope described in the claims of the present invention. This will be possible.

100: first case 104, 204: alignment hole
110,210: first and second contact parts 120: slot part
121: slot 130: coupling protrusion
140: Bulkhead 200: Second case
220: Adhesion surface 230: Coupling groove
240: Port 300: Radar antenna
S20,S60: Surface treatment process
S30,S70: Electroless metal plating process
S40,S80: Electrolytic metal plating process

Claims (22)

A surface treatment process that performs surface treatment of an injection molded product using plastic;
An electroless metal plating process that performs electroless metal plating on an injection molded product whose surface treatment has been completed;
It includes an electrolytic metal plating process that performs electrolytic metal plating of the electroless metal plated injection molded product,
The surface treatment process is,
An alkaline degreasing process of removing fat components attached to the surface of the injection molded product by immersing the injection molded product in an alkaline solution;
An alkaline etching process that etches the surface of the injection molded product through a chemical reaction using an alkaline etching solution,
A glass etching process to remove glass components present on the surface of the injection molded product,
Ultrasonic cleaning process that uses ultrasonic waves to clean the surface of the injection molded product,
Plating method of an antenna injection molded product, including.
The plating method of an antenna injection molded product according to claim 1, wherein the plastic is a PC (polycarbonate)-based amorphous engineering plastic.
The method of claim 1, wherein the plastic is a crystalline engineering plastic of the Liquid Crystal Polymer (LCP) or Polybutylene Terephthalate (PBT) series.
The plating method of claim 1, wherein in the alkaline degreasing process, the extruded product is degreased by immersing it in an alkaline degreasing solution with a concentration of 10% (v/v) at a temperature of 50° C. for 5 minutes, and then washed with water.
The antenna of claim 1, wherein in the alkaline etching process, the injection molded product is etched by immersing it in an etching solution containing 300 g/L of KOH and 50 ml/L of AD70B(S) for 5 to 10 minutes at a temperature of 65° C. and then washed with water. Plating method for injection molded products.
According to claim 1, In the glass etching process, the injection molded product is immersed in EC-LS(G) stock solution for 10 minutes at a temperature of 50° C., etched, and then washed with water.
The method of claim 1, further comprising a swelling process of swelling the surface of the injection-molded product as a process performed between the alkaline degreasing process and the glass etching process.
The method of claim 7, wherein in the swelling process, the surface of the injection-molded product is swelled at a temperature of 43° C. for 5 to 10 minutes using DMF stock solution.
The plating method of claim 7, wherein the process performed before the swelling process further includes a hot air drying process of drying the injection molded product that has undergone the alkaline degreasing process with hot air at a temperature of 60° C. for 10 minutes.
The method of claim 1, wherein in the ultrasonic cleaning process, the injection-molded product that has undergone the glass etching process is immersed in cleaning water at a temperature of 40° C. and then cleaned by applying ultrasonic waves for 5 minutes.
The method of claim 1, wherein the electroless metal plating process,
A conditioning process of cleaning the surface of the injection molded product after ultrasonic cleaning with a conditioner,
A first pre-dip process to primarily remove contaminants attached to the surface of the injection molded product,
A palladium catalyst treatment process that imparts conductivity to the surface of the injection molded product through a reduction reaction with a catalyst containing palladium (pd),
An activation process of activating the surface of the injection-molded product by immersing the injection-molded product in an activation treatment liquid;
A second pre-dip process to secondarily remove contaminants attached to the surface of the injection molded product,
An electroless copper plating process that forms a metal film on the surface of an injection product using an electroless method,
Plating method of an antenna injection molded product, including.
The method of claim 11, wherein in the conditioning process, the ultrasonic-cleaned injection-molded product is immersed in a KIAC-C surfactant solution with a concentration of 20% (v/v), washed at a temperature of 50° C. for 5 minutes, and then washed with water. Plating method.
The method of claim 11, wherein, in the first pre-dip process, the injection-molded product is treated by immersing it in an HCl solution with a concentration of 10% (v/v) at a temperature of 25° C. for 2 minutes.
The plating method of claim 11, wherein in the palladium catalyst treatment process, the extruded product is immersed in a mixed solution of 150 ml/L of HCl and 50 ml/L of CNI-S at a temperature of 35° C. for 5 minutes and washed with water.
The method of claim 11, wherein in the activation process, the injection-molded product is immersed in a 10% (v/v) H2SO4 solution at a temperature of 40° C. for 3 minutes and then washed with water.
The plating method of claim 11, wherein in the second pre-dip process, the extruded product is treated by immersing it in a formalin solution with a concentration of 5% (v/v) at a temperature of 25° C. for 2 minutes.
The method of claim 11, wherein in the electroless copper plating process, the injection product is mixed with a solution of 80 ml/L of ECP-80M and 40 ml/L of ECP-80M, or a mixture of 9 ml/L of NaOH and 8.8 ml/L of formalin. A plating method for an antenna injection molded product, which involves plating copper (Cu) by immersing it in a solution for 60 to 100 minutes at a temperature of 43°C and then washing it with water.
The method of claim 1, wherein the electrolytic metal plating process,
An electrolytic Ag-St plating process that forms an Ag-St metal film on the surface of the injection molded product by applying a current between the anode and the cathode;
An electrolytic Ag plating process to form an Ag metal film on the surface of the injection molded product on which the Ag-St metal film is formed;
A discoloration prevention process of treating the surface of the injection molded product on which the Ag metal film is formed to prevent discoloration using a discoloration prevention agent;
A hot air drying process in which the surface of the injection molded product treated to prevent discoloration is dried using hot air,
Plating method of an antenna injection molded product, including.
The method of claim 18, wherein in the electrolytic Ag-St plating process, the extruded product is immersed in a mixed solution of 3.1 g/L of AgCN and 110 g/L of KCN at a temperature of 25° C. for 0.5 minutes, and a 3V voltage is applied to perform electrolytic plating. A plating method for antenna injection molding products, which includes washing with water.
The method of claim 18, wherein in the electrolytic Ag plating process, the extruded product is immersed in a mixed solution of 37.5 g/L AgCN and 80 g/L KCN at a temperature of 25° C. for 5 to 15 minutes and a current of 0.5 A/dm2 is applied. A plating method for antenna injection-molded products that involves electrolytic plating and washing.
The method of claim 18, wherein in the discoloration prevention process, the extruded product is immersed in a solution containing a discoloration prevention agent at a concentration of 0.5% (v/v) for 1 minute at a temperature of 55° C. and then washed with water.
The method of claim 18, wherein in the hot air drying process, the electrolytic silver (Ag) plated injection molded product is hot air dried using hot air at 60° C. for 10 minutes.

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