KR101232718B1 - Method for preparing molded product using plated resin - Google Patents

Abstract

PURPOSE: A manufacturing method of a molded product using a plated raw material resin is provided to perform chemical plating on a material resin to provide electric conductivity to the material resin for electrical plating followed by injection molding, thereby acquiring a metallic appearance without a post-manufacturing process. CONSTITUTION: A manufacturing method of a molded product using a plated raw material resin comprises the steps of: providing electric conductivity to a pellet type material resin on which chemical plating is performed(S30); performing electric plating on the chemically plated material resin(S40); and injection-molding the electrically plated material resin(S50). The material resin is a thermoplastic resin. [Reference numerals] (AA) Raw material resin; (BB) Final molded body; (S10) First preprocessing step(pre-etching, etching, conditioning process); (S20) Second preprocessing step(palladium absorption process); (S30) Chemical plating; (S40) Electric plating; (S50) Injection-molding

Description

Manufacturing method of molded article using plated raw resin {METHOD FOR PREPARING MOLDED PRODUCT USING PLATED RESIN}

The present invention relates to a method for producing a molded article having a metallic appearance through injection molding.

In various types of injection molded products such as household appliances and mobile phones, a surface treatment process (hereinafter referred to as "post-processing") for processing the surface of the molded body after injection can be said to be essential.

Such post-processing processes include spray printing, masking printing, film insertion, printing, and deposition processes. These post-processing processes can increase the cost of products and increase the defect rate according to the progress of the post-processing process. The method has a limit in realizing the appearance of metallic feeling.

As a post-processing process for imparting a metallic appearance to the injected molded body, the method of coating after the deposition on the molded body and the method of plating the molded body are used (Korean Patent Publication Nos. 2010-29502 and 2010-30961). These methods also suffer from increased defect rates and production costs, as well as limited implementation colors.

Republic of Korea Patent Application Publication No. 2010-29502 Republic of Korea Patent Application Publication No. 2010-30961

Accordingly, it is an object of the present invention to provide a method for producing a molded article having a metallic appearance without such a post processing step.

According to the above object, the present invention comprises the steps of (a) performing chemical plating on the raw resin to impart electrical conductivity; (b) electroplating the chemically plated resin; And (c) injection molding the electroplated resin.

The present invention also provides a molded article produced by the above method.

The manufacturing method of the molded article according to the present invention, unlike the conventional method of undergoing post-processing such as plating after injection of the raw material resin, to obtain a molded body of the metallic appearance directly through the injection does not require a post-processing process, In addition to eliminating the cause of defects and significantly lowering the production cost, the color implementation is more free since it does not obstruct or harm the basic color of the raw resin.

1 shows a flow of a process for producing a shaped body according to one embodiment of the invention.
2 is an example of a process for pretreating and plating an ABS raw material resin according to the present invention ((a) ABS resin, (b) etching, (c) Pd adsorption, (d) chemical plating, and (e) electroplating) .
3 is an example of a process for pretreating and plating PC raw material resin according to the present invention ((a) PC resin, (b) preetching, (c) etching, (d) conditioning, (e) Pd adsorption, (f) A) chemical plating, and (g) electroplating).
4 is a schematic view showing a process of injection molding the plated raw resin.
5 is a photograph comparing before and after plating of various raw material resins according to the present invention:
(a) before plating— (a-1) PC, (a-2) ABS, (a-3) colored PC, and (a-4) colored PC; And
(b) after plating— (b-1) after electroless nickel plating, (b-2) after chemical copper plating, and (b-3) after electroplating.
6 is a schematic view and photograph showing a cross section of a molded article produced according to the present invention.
7 is a photograph of one of the shaped bodies produced according to the present invention.

Hereinafter, a method of manufacturing a molded article according to the present invention will be described in more detail step by step with reference to the drawings.

Preparation of Raw Resin

The raw material resin used in the present invention is not particularly limited as long as it is a resin that can be manufactured into a molded body through injection molding. Thermoplastic resins are possible.

More specifically, Polyolefin resin, such as polyethylene (PE) and polypropylene (PP); Polyester-based resins such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polycarbonate (PC); Polyether resins such as polyacetal, polyphenylene oxide (PPO), polysulfone (PSF), polyether sulfone (PES), polyether ether ketone (PEEK), and the like; Polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyvinyl alcohol (PVAL), polyvinyl acetal, polystyrene (PS), acrylonitrile styrene (AS), acrylonitrile-butadiene-styrene (ABS), Polyvinyl resins such as polymethyl methacrylate (PMMA); Polyamide resins such as nylon; Or mixtures thereof.

Although the form of the raw material resin used by this invention is not restrict | limited greatly, It is preferable that it is a pellet form.

Pretreatment of Raw Resin

The prepared raw resin may be subjected to a pretreatment step to make a surface state suitable for plating (S10 and S20 of FIG. 1).

In the first pretreatment step, pre-etching, etching, and conditioning may be performed.

The pretreatment step may be, for example, undergoing only an etching process, a preetching and etching process, an etching and conditioning process, or a conditioning process after preetching and etching.

Pre-etching process can be performed by processing raw material resin at the temperature of 65-75 degreeC using the organic solvent, caustic soda, etc.

In addition, the etching process is to form fine pores or surface roughness through corrosion of the surface of the raw material resin using an etching solution such as acid, chromic anhydride (CrO ₃ ), sulfuric acid (H ₂ SO ₄ ), trivalent chromium (Cr It can carry out by processing raw material resin at the temperature of 55-65 degreeC using the etching solution containing ⁺³ ) and the like. In addition, after the etching process may be subjected to a water washing process for removal of the etching solution, and even if the removal of the etching solution through the water washing may be subjected to a hydrochloric acid dipping process for removing the residue.

The conditioning process can be carried out by treating the raw resin etched at a temperature of 30 to 40 ° C. using a commercially available CT-100 manufactured by A & D Korea.

In addition, as a second pretreatment step, the surface of the fine pores of the raw material resin may be subjected to a process of adsorbing a palladium (Pd) catalyst nucleus necessary for initiation of a subsequent chemical plating reaction.

Such a palladium adsorption process may be made of a palladium-tin catalyst, for example, using tin chloride and palladium chloride or commercially available PAL-8 from Isc Tech or Yushin Technopia. The palladium can be adsorbed on the surface of the raw material resin by treating the raw material resin for 2 to 10 minutes at.

In addition, after palladium adsorption, a step of dropping the tin component precipitated on the surface may be added. For example, the raw material resin may be treated with sulfuric acid or hydrochloric acid at 25 to 40 ° C. for 30 seconds to 10 minutes.

The preferred treatment condition ranges for these pretreatment drugs are summarized in Table 1 below.

2 and 3 show an example of a pretreatment process of an ABS resin and a PC resin.

As shown in FIG. 2, a pretreatment comprising the steps of (a) oxidizing elution of butadiene particles into an ABS resin pellet through chemical etching to form fine pores and (c) adsorbing a palladium catalyst nucleus on the etched surface. The process can be carried out.

In addition, as shown in Figure 3, (a) PC resin pellets (b) pre-etching (c) etching, (d) after the conditioning step (e) adsorbing the palladium catalyst nucleus on the surface The pretreatment process containing can be implemented. In the case of PC resins, palladium can be activated by conducting a conditioning process that additionally accelerates the surface before the palladium adsorption process.

As described above, the raw material resin subjected to the pretreatment process is chemically plated (FIGS. 2D and 3F) and electroplating (FIGS. 2E and 3G). You will go through additional.

Chemical Plating Of Raw Resin

The raw material resin, which has undergone pretreatment or the like, is provided with electrical conductivity through chemical plating (S30 of FIG. 1).

Chemical plating can be performed using chemical copper or electroless nickel.

For example, in the case of chemical copper plating, plating may be performed at 27 to 30 ° C. with a plating solution containing copper, sodium hydroxide, and formaldehyde.

In addition, in the case of electroless nickel plating, plating can be performed at 87-92 degreeC with the plating solution containing nickel, for example.

Preferred process conditions for such chemical plating are summarized in Table 1 below.

Electroplating of Raw Resin

The raw material resin subjected to chemical plating is then subjected to electroplating to give a metallic appearance (S40 of FIG. 1).

Electroplating can be carried out using copper lactate, nickel, trivalent chromium, ternary alloys, etc. In electroplating, the alternating current is converted to direct current through a rectifier to supply metal ions from the anode to the cathode.

For example, in the case of copper lactate electroplating, a plating solution containing copper sulfate and sulfuric acid may be performed at a current of 1 to 4 A / dm 2 at a temperature of 20 to 40 ° C. for 2 to 20 minutes.

In the case of nickel electroplating, a plating solution containing nickel sulfate, nickel chloride, boric acid, and the like may be performed at a temperature of 50 to 55 ° C. for 2 to 20 minutes at a current of 2 to 6 A / dm 2 at pH 4 to 5 minutes. Can be.

In the case of trivalent chromium electroplating, a plating solution containing chromium compound, hydrochloric acid, sulfuric acid, etc. is performed at a current of 4 to 15 A / dm 2 at pH 3.3 to 3.6 for 2 to 20 minutes at a temperature of 45 to 55 ° C. can do. For example, commercially available products of McDermid (Salts, Part 1, Initial, etc.) may be used.

In addition, in the case of ternary alloy electroplating, a plating solution containing copper cyanide (CuCN), tin (Sn), zinc (Zn), sodium cyanide (NaCN), and sodium hydroxide (NaOH) has a temperature of 50 to 60 ° C. Can be performed at a current of 2 to 6 A / dm 2 under pH 12 to 14 for 2 to 10 minutes.

The detailed process condition range of such electroplating is summarized in Table 1 below.

As such, the raw material resin having the plating may have a plating layer having a thickness of about 0.1 μm to 10 μm.

As a result, it may have a metallic appearance compared to the raw resin before plating. 5 is a photograph comparing before and after plating various raw material resins according to the present invention, before ((a-1) PC, (a-2) ABS, (a-3) colored PC, and (a-4) before plating. ) The appearance of the raw material resin after plating ((b-1) after electroless nickel plating, (b-2) after chemical copper plating, and (b-3) after electroplating) as compared with the raw resin of colored PC) It can be confirmed that the metallic plating on.

Process Name Drug name Drug concentration Processing temperature Processing time PH condition Current applied


Pretreatment
step Pre-etching Organic solvent 200 ~ 300ml / ℓ 55 ~ 65 ℃ 1-10 minutes - - Caustic soda 400 ~ 500g / ℓ 55 ~ 65 ℃ 1-10 minutes - -
etching CrO ₃ 550 ~ 600g / ℓ
65 ~ 75 ℃
3 ~ 10 minutes
-
- H ₂ SO ₄ 200 ~ 300ml / ℓ Cr ⁺³ 10g / ℓ or less Conditioning CT-100 1-1.3% 30 ~ 40 ℃ 1-10 minutes - - Pd adsorption PAL-8 25 to 35% 20 ~ 40 ℃ 2-10 minutes - - HCI 250 ~ 350ml / ℓ
Chemical plating
Chemical copper NaOH 4.0 ~ 8.0g / ℓ
27 ~ 30 ℃
1-15 minutes
-
- HCHO 1.0 ~ 3.0g / ℓ Cu 1.2 ~ 2.2g / ℓ Electroless Nickel Ni 4.5 ~ 6.0g / ℓ 87 ~ 92 ℃ 1-15 minutes - -




Electrical
Plated Heritage building CuSO ₄ 170 ~ 210g / ℓ 20 ~ 40 ℃ 2-20 minutes - 1 ~ 4A / dm H ₂ SO ₄ 50 ~ 60g / ℓ
nickel NiSO ₄ .6H ₂ O 450 ~ 550g / ℓ
50 ~ 55 ℃
2 ~ 20 minutes
4 ~ 5
2 ~ 6A / dm NiCl ₂ .6H ₂ O 25 ~ 45g / ℓ H ₃ BO ₃ 30 ~ 60g / ℓ
Trivalent chrome Salts 260 ~ 320g / ℓ
45 ~ 55 ℃
2-20 minutes
3.3 ~ 4.5
4 ~ 15A / dm2 Part 1 7 ~ 11g / ℓ Initial 8-12ml / ℓ

Ternary alloy CuCN 10 ~ 14g / ℓ

50 ~ 60 ℃

2-10 minutes

12-14

2 ~ 6A / dm NaCN 35 ~ 45g / ℓ NaOH 20 ~ 30g / ℓ Sn 32 ~ 38g / ℓ Zn 0.8 ~ 1.2g / ℓ

Injection molding

The raw resin plated in this way is molded through injection molding (S50 in FIG. 1).

Specifically, as shown in Fig. 4, the plated resin 10 is injected into an injection molding machine, melted, injected with mixing by a screw 20, injected into a mold 30 of a desired shape, and then cooled to a desired molded body. Can be obtained.

The injection process can be carried out by, for example, single injection, double injection, insert injection, or the like.

Result molded body

The molded article manufactured in the above manner is metallic and even without a separate post-processing process, for example, powder coating, metal powder injection, pearl particle coating, deposition, etc. It may have an appearance of metal particles.

6 is a schematic view and a real picture showing a cross section of a molded article produced according to the method of the present invention. Looking at the cross section of the manufactured molded article has a form in which the fine plated particles 50 are dispersed in the raw material resin 40. This is because the plating material diffused in the raw resin through melting during injection.

Figure 7 is a photograph of one of the molded articles produced according to the present invention, it can be seen that the appearance of the excellent metallic appearance due to the plated particles exposed on the surface without harming the color of the raw resin.

Hereinafter, the present invention will be described through more specific examples. However, the following examples are merely examples of the present invention and the scope of the present invention is not limited thereto.

Example 1 Plating and Injection Molding of ABS Resin

ABS resin (MP0660 of Cheil Industries) was prepared as raw material resin.

The ABS resin was treated at 73 ° C. for 3 minutes using an etching solution (composition: CrO ₃ 550-600 g / l, H ₂ SO ₄ 200-300 ml / l and Cr ⁺³ 10 g / l or less).

The etched ABS resin was then treated at 33 ° C. for 5 minutes using a solution for adsorption of Pd on the surface (composition: 25-35% PAL-8 from Yusin Technopia, and 250-350 ml / l HCl).

Thereafter, the Pd-adsorbed ABS resin was treated at 88 ° C. for 5 minutes using a plating solution (composition: electroless nickel plating solution containing Ni 4.5˜6.0 g / L) for chemical plating.

Then, the electroplating solution was chemically plated using a plating solution (composition: Salts 260-320 g / l, Part 1 7-11 g / l and Initial 8-12 ml / l) of McDermid for 47 ° C. Electroplating was performed at a current of 10 A for 15 minutes under the condition of pH 4.5.

The plated resin was injected into a mold in the form of a double injection plate at a temperature of 240 ° C. using a double injection molding machine (FCS Korea Co., Ltd. FCS-140T). After cooling at 60 ° C., the molded body was separated from the mold.

Example 2: Plating and Injection Molding of PC Resin

PC resin (TN1045S of Cheil Industries) was prepared as raw material resin.

PC resin was processed at 55 degreeC for 3 minutes using the preetching solution (composition: 200-300 mL / L of organic solvents). The PC resin was then treated at 73 ° C. for 4 minutes using an etching solution (composition: CrO ₃ 550-600 g / l, H ₂ SO ₄ 200-300 ml / l and Cr ⁺³ 10 g / l or less). After that, the PC resin was treated at 35 ° C. for 7 minutes using a conditioner (composition: CT-100 1-1.3% of A & D Korea).

The PC resin was then treated at 33 ° C. for 10 minutes using a solution for adsorption of Pd on the surface (composition: PAL-8 25-35% and HCI 250-350 mL / L).

Then, the Pd adsorbed PC resin was treated at 88 ° C. for 5 minutes using a plating solution (composition: electroless nickel plating solution containing Ni 4.5˜6.0 g / L) for chemical plating.

Then, the electroplating solution was chemically plated using a plating solution (composition: Salts 260-320 g / l, Part 1 7-11 g / l and Initial 8-12 ml / l) of McDermid for 47 ° C. Electroplating was performed at a current of 10 A for 15 minutes under the condition of pH 4.5.

The plated resin was injected into a mold of a double injection flat plate at a temperature of 300 ° C. using a double injection molding machine (FCS Korea Co., Ltd. FCS-140T). After cooling at 90 ° C., the molded body was separated from the mold.

In the above, the present invention has been described with reference to the above embodiments, which are only examples, and the present invention includes various modifications and other equivalent embodiments which are obvious to those skilled in the art. It should be understood that it can be carried out within the scope of the appended claims.

10: plated raw resin 20: screw 30: mold
40: raw material resin (molded product) 50: plated particles

Claims (8)

(a) chemically plating the raw material resin in pellet form to impart electrical conductivity;
(b) electroplating the chemically plated resin; And
(c) injection molding the electroplated resin;
delete The method of claim 1,
The raw material resin is a thermoplastic resin, characterized in that the manufacturing method of the molded body.
The method of claim 1,
Before the step (a), further comprising the step of adsorbing palladium (Pd) to the raw material resin, characterized in that the manufacturing method of the molded body.
The method of claim 1,
Before the step (a), further comprising the step of treating the raw material resin with an etching solution, the manufacturing method of the molded body.
The method of claim 1,
In the step (a), characterized in that the chemical plating is carried out using chemical copper or electroless nickel.
The method of claim 1,
In the step (b), characterized in that the electroplating is carried out with a current of 1 to 15 A / dm 2 using copper lactate, nickel, trivalent chromium, or ternary alloy.
A molded article produced by the method of any one of claims 1 and 3.

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