KR101509473B1 - Synthetic Resin Electro-less Intenna Plating Method and Rear Case thereof - Google Patents

Abstract

A synthetic resin electro-less intenna plating method and a rear case thereof are provided to simplify the process, to improve adhesion of a plating layer, to induce an eco-friendly enviornment, and to achieve economic feasibility, reliability of product, and eco-friendly property. The method comprises: a laser processing step of irradiating a laser to an area to be plated on the surface of synthetic resin materials, to form bumps, and to create circuit patterns; an ultrasonic wave cleaning and penetration step of infiltrating a cleaning solution into the floor with the bumps and performing cleaning using ultrasonic waves; an activation step of infiltrating a catalyst into the floor with the bumps with a guiding means so that the catalyst can be adsorbed to the guiding means; a plating step of plating circuit patterns with the bumps with copper and nickel; and a post-processing step of post-processing the nickel-coated surface.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of plating a synthetic resin electroless stainless steel and a rear case using the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin electroless innene plating method and a rear case therefor, and more particularly to a synthetic resin electroless innene plating method which improves a conventional plating process and a rear case therefor.

Generally, a mobile device such as a smart phone having an antenna protruding to the outside of a transmission / reception device or a mobile phone has difficulty in diversification and slimming of the design, so that the antenna is connected to the printed circuit board inside the mobile device housing, Among antennas, what is designed to maintain antenna characteristics is called an antenna.

These intenna not only can design various designs of mobile devices, but also provide advantages of slimming down the thickness of mobile devices.

Intenna is manufactured by two methods in three ways. These methods are as follows.

In one method, a housing and a printed circuit board are disposed according to the design of a mobile device, a space for installing the intenna is determined, a plastic injection mold corresponding to the space is formed, a press mold corresponding to the intenna circuit pattern is formed on the injection- Or a stainless steel thin plate or the like, bending it, sandwiching it on the base, and fixing it by thermal fusion to add the function of intenna.

Another method is to design a circuit pattern on the base designed according to the shape of the internal space of the intenna by the double injection method, and then to fabricate the base injection mold and the circuit pattern injection mold in conjunction with each other, And a circuit pattern is formed on the base while being double injected with a plastic material of another component. Electroless plating is performed only on the circuit pattern portion of the double-printed product to manufacture the intenna. However, the double injection method has a disadvantage in that it takes a lot of time and cost in the mold making period and it takes much time for the mold development.

Another method is a laser method in which a metal component and a filler, which are active agents, are mixed and used so as to be plated with a plastic raw material. This method is called Laser Direct Structuring (LDS) method because it manufactures intenna by processing a circuit pattern on an injection molded product with a laser, and it can save time in development or manufacturing process, It is one of the latest technologies. In other words, since the metal component, which is the seed of the plating, is mixed in the resin, the etching time, the neutralization process, and the activation process are omitted compared to the process according to the double injection method, . An example of such an ELISA plating method is disclosed in Korean Patent No. 10-1167568.

Another method is electroless plating by irradiating a general-purpose synthetic resin with a laser. A typical synthetic resin is PC (Poly Carbonate). However, in this conventional method, when the laser is applied to the synthetic resin, the PC remnants generated by the heat of the laser (hereinafter referred to as " laser hair after the laser processing ") remain, and the plating solution can not penetrate to the bottom surface of the laser processing. There is a problem that defects occur in the adhesion test, which is a reliability test item.

That is, although the conventional plating method has been pre-etched and etched, it is difficult to penetrate to the bottom surface of the laser processing so that plating is progressed on the surface, resulting in repeated failure due to insufficient adhesion. Various etching methods solve this problem I am trying to. The etching solution is chromic acid (CrO3) and sulfuric acid (H2SO4), which are toxic substances and are designated as hazardous and environmentally hazardous substances. An example of such a conventional technique is Korean Patent Registration No. 10-1258145 (published on March 26, 2013).

An object of the present invention is to provide a method of plating a synthetic resin electroless intenna capable of shortening the process simply and conveniently and a rear case therefor.

It is also an object of the present invention to provide a method of plating a synthetic resin electroless intenna capable of penetrating a plating layer to a bottom surface of a molten hair protrusion without damaging the molten hair protrusion formed in laser processing, and a rear case therefor.

Another object of the present invention is to provide a synthetic resin electroless innene plating method capable of improving the adhesion of a plated portion and a rear case therefor.

Still another object of the present invention is to provide an environmentally friendly synthetic resin electroless innene plating method without using environmentally harmful substances and a rear case therefor.

An object of the present invention is to provide a method of manufacturing a synthetic resin electroless plating method, which comprises: a laser processing step of irradiating a region to be plated on the surface of a synthetic resin material with a laser to form a furrow- An ultrasonic cleaning and infiltrating step of infiltrating the cleaning liquid into the bottom surface of the flecking protrusion and cleaning the ultrasonic cleaning liquid by ultrasonic waves; An activating step of introducing the catalyst into the bottom surface of the flecking protrusion and guiding the catalyst so that the catalyst can be guided to the bottom surface of the fleeing protrusion; A plating step of performing copper plating and nickel plating on the circuit pattern on which the fur protrusions are formed; And a post-treatment step of post-treating the nickel-plated surface.

The ultrasonic cleaning and infiltration step S115 is a mixed solution of pure water 30 to 50 wt% and methanol 50 to 70 wt%, and the temperature of the treatment solution is maintained at 20 to 50 DEG C, It is preferable to immerse the material for about 5 minutes and clean it with ultrasonic waves.

In addition, in the activating step, the guiding means preferably includes a metal ion reducing agent containing dimethylglyoxime as a solution that overcomes the surface tension of the flecking protrusion and is permeable to the bottom surface on which the fleeing protrusion is formed.

In addition, the guide means is preferably mixed with ethanol.

On the other hand, the object of the present invention is also achieved by a rear case for an electromagnetic device including intenna manufactured by a method of electroless plating of synthetic resin.

According to the present invention, since the conventional pre-etching process and / or etching process can be eliminated, the process can be shortened, the working time can be shortened and the economical efficiency can be improved and the adhesion of the plated portion can be improved, It is possible to improve the quality and reliability of the product, and it is possible to provide an environmentally friendly synthetic resin electroless innene plating method without environmentally harmful substances, and a rear case therefor.

1 is a schematic process diagram of an electroless plating method according to an embodiment of the present invention,
2 is a cross-sectional enlarged photograph taken after the laser processing step according to another embodiment of the present invention,
FIGS. 3A and 3B are photographs showing enlargement of a plane after the laser processing step and photographs of enlarged planes after the conventional pre-etching and etching process,
FIG. 4 is a photograph showing an enlarged plane after the ultrasonic cleaning and penetration step,
5A and 5B are comparative photographs of adhesive force test results of a conventional electroless plating method and an electroless plating method according to the present invention.

The synthetic resin electroless innate plating method and the rear case therefor according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 5B.

FIG. 1 is a schematic process diagram of an electroless plating method according to an embodiment of the present invention, FIG. 2 is a magnified (20 times) photograph taken after a laser processing step according to another embodiment of the present invention, FIG. 3B is an enlarged (100 times) plane after the laser processing step and an enlarged (100X) plane after the conventional pre-etching and etching process, and FIG. 4 is an enlarged view of the plane after the ultrasonic washing and penetrating step 5A and 5B are comparative photographs of adhesive force test results of a conventional electroless plating method and an electroless plating method according to the present invention.

The synthetic resin electroless innate plating method according to one embodiment of the present invention and the rear case (hereinafter, referred to as 'electroless plating method') will be described in detail with reference to FIG.

The electroless plating method includes a laser processing step S110, an ultrasonic cleaning and infiltration step S115, an activation step S120, an activation step S125, a nickel strike step S130, , A copper plating step (S135), a nickel activation step (S160), a nickel plating step (S170), and a post-processing step (S180).

In the laser processing step (S110), a laser is irradiated to a region to be plated in a general-purpose synthetic resin (for example, PC (Poly Carbonate)). When the synthetic resin is irradiated with a laser beam, PC residuals (hereinafter referred to as " fur hair projections ") generated by the heat of the laser are formed at a certain depth from the surface of the synthetic resin so that the plating circuit pattern can function as an intenna 2 and Fig. 3A).

In the etching process of the conventional double injection plating method, butadiene, which is the B component of the ABS resin, is melted to form fine pores, and palladium, which is a metallic component, is adsorbed in the pores to enable copper plating and nickel plating.

In addition, in the conventional LDS plating method, a metal component is mixed in a resin and used, so that metal particles are embedded in the resin after the laser processing, thereby playing a role of a seed of plating, thereby enabling copper plating and nickel plating.

On the other hand, in the present invention, the surface of the synthetic resin is irradiated with a laser to form a furrow protrusion on the surface to form a base or a root for supporting a plated region. However, such a molten projections prevent the plating solution from penetrating to the laser processing floor in the subsequent plating process. The reason is due to the frequency and surface tension of the molts. Therefore, a pre-etching process and an etching process have conventionally been carried out as a method of reducing the frequency of the fringe protrusions that hinder penetration of the plating liquid. The etchant used in such an etching process contains chromic acid and sulfuric acid and is not effective in reducing the permeability of the solution because it does not effectively reduce the frequency of the flounder of the synthetic resin when etching into an acid. On the other hand, even if a method of significantly reducing the flecking protrusions is taken, it is not preferable because there are few fringe protrusions serving as a base for supporting the plating (see Fig. 3B).

In the ultrasonic cleaning and infiltration step (S115), the surface tension generated due to the molten hair protrusion generated in the laser processing step (S110) is overcome and processed so as to penetrate to the bottom surface of the laser processing. The treatment solution used in this step S115 is a mixed solution of 30 to 50 wt% of pure water and 50 to 70 wt% of methanol (methanol, CH3OH), and the treatment solution is maintained at a temperature of 20 to 50 DEG C, Min to immerse the material in order to maximize the effect of washing and penetration, and to adjust the frequency of the ultrasonic wave to about 28 to 45 KHz so as to penetrate the fine portion. FIG. 4 is a photograph showing an enlarged view of the surface of the material that has undergone the ultrasonic cleaning and infiltration step S115.

The activation steps S120 and 125 are divided into an activation step S120 and an activation step S225.

In the activation step S120, the surface tension of the molten hair protrusion is maintained in a state of being exhausted, so that dimethyl-glyoxime penetrates the bottom surface of the laser processing, and the metal palladium ion is adsorbed in the next step of activation step S125 So that plating can be easily performed. Ethanol (Ethanol) is used to dissolve dimethylglyoxime to control its concentration. This dimethylglyoxime adsorbs and reduces the catalyst described below. Here, dimethylglyoxime is exemplified, but it is preferable that the present invention includes a dimethylglyoxime metal ion reducing agent.

The composition ratio of the permeate is 30 to 50 wt% pure water mixed with 500 ml / liter of dimethyl-glyoxime (hereinafter referred to as 'liter' or 'L') and 500 ml / %, Mixture liquid 50 ~ 70 wt%, working temperature 10 ~ 30 ℃, working time 3 ~ 15 minutes.

Activation step 2 (S125) is a step of adding a catalyst to metallize the PC laser machining surface. The catalyst to be added is generally palladium (Pd) which is the most commonly used, and its effect is also excellent, and the form of the catalyst is ion (Ion). The solution containing the catalyst is 0.8-1.0 g / l of palladium, 100-450 ml / l of sulfuric acid (H2SO4), and 550-900 ml / l of pure water. The working temperature in this step (S125) ~ 5 minutes.

That is, the catalyst serves as a guide for allowing the catalyst of the activation step 2 (S125) to infiltrate to the bottom surface of the molten hair protrusion in the first activation step (S120), and the guide (dimethylglyoxime) The adhesion of the plating layer, which will be described later, can be excellently maintained.

The nickel strike step (S130) is a step of laser-machining and applying a catalyst to a slightly coarse circuit pattern to conduct nickel plating, thereby confirming and verifying the shape in which the nickel particles are formed on the processed circuit pattern. The tub bath ratio of the nickel strike step S130 is as follows. (5 to 7 g / l), pH 5.5 (4.5 to 7.0), temperature 65 (55 to 75), plating thickness 1 to 5, sodium hypophosphite and stabilizer 25 g / l (22 to 30 g / l).

In the copper plating step (S135), the plating solution may contain pure water 700 to 800 ml / L, metal copper 3 to 5 g / L (for example, ELC 1000-M 110 ml / m), stabilizer and accelerator 20 to 40 ml / ELC 1000-B 20 to 40 ml / l), sodium hydroxide (NaOH) 8 to 10 g / L and formalin (HCHO) 3 to 5 g / Dip material for about 300 minutes. The copper thickness after copper plating is confirmed, and a copper thickness of 6 to 15 mu m is preferable.

After plating, it is preferable to analyze the plating solution to supplement the deficient components, and the replenishing solution to be used is used in an average of about 5 to 20 ml / L (for example, ELC 1000-A).

(100 to 100 ml / L), 50 to 100 ml / L of sulfuric acid (H2SO4) and 800 to 900 ml / L of pure water as a treatment solution in the nickel activation step (S160) , Soak the material for 2 to 7 minutes. In this step S160, activation of the palladium catalyst ions particularly on the surface of the copper plating layer is vigorously activated, so that nickel ions are precipitated as metal particles in an electroless nickel plating step (S170) as a post-process to obtain a uniform nickel plating layer .

In the nickel plating step S1170, a nickel metal film is formed on the circuit pattern. The tub bath costs are as follows. (Gem ENI (germanium oxide)) was used as the anode active material, and the thickness of the plating bath was 1 to 5 탆. (22 ~ 30 g / l), 50 g / l (44-52 g / l) of sodium hypophosphite, and 25 g / l of stabilizer (Gem ENI Black B). In addition, the content of phosphorus, which affects the luster, is 1 to 3%, belonging to the dwarf, and the luster appears as a reflex between luster and matt.

In the post-treatment step (S180), when the electroless plating is completed, nickel is bonded with oxygen in the atmosphere and oxidation occurs to change the color of the white surface. This is a process for preventing the discoloration phenomenon. The solution used in the post-treatment step S180 is a solution containing 10 to 15 g / L of isopropyl alcohol, 13 to 25 g / L of propylene glycol, 6 to 10 g / L of fatty acid organic compound, 900 to 950 mg / L, and in the post-treatment step (S180), it is preferable that the material is immersed in the solution for 1 to 5 minutes while the pH is maintained at a neutral pH of 6.0 to 7.5 and a temperature of 25 to 55 ° C.

The final stage of the packaging process (not shown) is a process of washing and drying the product, washing the product, drying the product, and finally packaging the product.

(3M-610) was attached to the surface of the plating to expose the exposed surface of the nail plate (3M-610) at room temperature for 1 hour after exposed to the high temperature and high humidity environment (temperature 70-80 degrees, humidity 80-90% , The bubbles were removed, and the tape was separated with a proper force to determine the extent of the plated surface being dropped, and the adhesion test of the plated layer (surface) was performed. A photograph of this adhesion test result is shown in FIG. 5B, and a comparative example plated through a pre-etching and etching process according to the prior art is shown in FIG. 5A.

The plating layer of FIG. 5B according to the present invention maintains a much better adhesion to the synthetic resin, which is a raw material, than the plating layer of FIG. 5A of the prior art.

Although PC (Poly Carbonate) is used for the synthetic resin used in the present invention, it is needless to say that it can be changed into various known types.

According to the present invention, when electroless plating is performed on a general-purpose synthetic resin, the process can be simplified and the adhesion of the plating layer can be remarkably improved by a method capable of plating without using a conventional pre-etching step and an etching step. For example, when manufacturing intenna of an electronic device such as a smart phone, it is possible to prevent a variety of accidents that may occur due to lifting of the plated pattern from high temperature and high humidity. In addition, it is possible to eliminate the etching process which is particularly harmful in the conventional plating process while having excellent adhesion, and cost reduction and environment friendliness can be simultaneously obtained.

As described above, according to the present invention, since the conventional pre-etching process and / or etching process can be eliminated, the process can be shortened and the working time can be shortened, thereby improving the economical efficiency and improving the adhesiveness of the plated portion It is possible to prevent the lifting phenomenon in a high temperature and high humidity environment, thereby improving the quality and reliability of the product, and it is possible to provide an environmentally friendly synthetic resin electroless innene plating method without use of environmentally harmful substances and a rear case therefor.

It goes without saying that the rear case for an electromagnetic device including a cellular phone including intenna and intenna manufactured and manufactured by this method has the same effect.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the invention. will be. The scope of the invention will be determined by the appended claims and their equivalents.

Claims (5)

A method for electroless plating a synthetic resin,
A laser processing step of irradiating a region of the synthetic resin material to be plated with a laser beam to form a furrow protrusion to generate a circuit pattern;
An ultrasonic cleaning and infiltrating step of infiltrating the cleaning liquid into the bottom surface of the flecking protrusion and cleaning the ultrasonic cleaning liquid by ultrasonic waves;
An activating step of introducing the catalyst into the bottom surface of the flecking protrusion and guiding the catalyst so that the catalyst can be guided to the bottom surface of the fleeing protrusion;
A plating step of performing copper plating and nickel plating on the circuit pattern on which the fur protrusions are formed;
A post-treatment step of post-treating the nickel plated surface,
In the activating step, the guiding means may include a metal ion reducing agent containing dimethylglyoxime as a solution that overcomes the surface tension of the flecking protrusion and is permeable to the bottom surface on which the fleeing protrusion is formed A method for electroless plating a synthetic resin,
A laser processing step of irradiating a region of the synthetic resin material to be plated with a laser beam to form a furrow protrusion to generate a circuit pattern;
An ultrasonic cleaning and infiltrating step of infiltrating the cleaning liquid into the bottom surface of the flecking protrusion and cleaning the ultrasonic cleaning liquid by ultrasonic waves;
An activating step of introducing the catalyst into the bottom surface of the flecking protrusion and guiding the catalyst so that the catalyst can be guided to the bottom surface of the fleeing protrusion;
A plating step of performing copper plating and nickel plating on the circuit pattern on which the fur protrusions are formed;
A post-treatment step of post-treating the nickel plated surface,
The ultrasonic cleaning and infiltration step S115 is a mixed solution of 30 to 50 wt% of pure water and 50 to 70 wt% of methanol, and the temperature of the treatment solution is maintained at 20 to 50 DEG C for 1 to 5 minutes The material is immersed and washed with ultrasonic waves,
Wherein the guide means comprises a metal ion reducing agent containing dimethylglyoxime as a solution that overcomes the surface tension of the flecking protrusion and is permeable to the bottom surface on which the fleeing protrusion is formed, Plating method. delete 3. The method according to claim 1 or 2,
Wherein the guide means is mixed with ethanol. ≪ RTI ID = 0.0 > 8. < / RTI > A rear case for an electromagnetic device comprising an intenna manufactured by the method of the electroless plating of synthetic resin according to claim 1 or 2.

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