阅读说明：本技术 一种塑料件表面选择性电镀方法 (Selective electroplating method for surface of plastic part ) 是由 李琴芳 于 2020-04-27 设计创作，主要内容包括：本申请实施例示出了一种塑料件表面选择性电镀方法,方法包括：将经过沉钯解胶后的塑料件,进行化学镀镍；在化学镀镍后的塑料件的表面进行激光镭射,形成阻隔线,阻隔线将塑料件表面分割为电镀区和非电镀区；采用酸铜在电镀区上进行电镀薄铜处理后,电镀区形成镀薄铜层；在电镀薄铜处理后的塑料件的表面进行退化学镍处理；在退化学镍处理后的塑料件的镀薄铜层上进行电镀厚铜处理后,电镀区形成镀厚铜层。电镀方法采用酸铜首先在塑料件表面的电镀区进行电镀薄铜处理,酸铜可以溶解化学镀镍过程中溢镀的镍,提高镍层的平整度,进而提高后期金属走线的侧面平整度,提升整个器件的电路电气性能。(The embodiment of the application discloses a method for selectively electroplating the surface of a plastic part, which comprises the following steps: carrying out chemical nickel plating on the plastic part subjected to palladium precipitation and peptization; carrying out laser on the surface of the plastic part after the chemical nickel plating to form a barrier line, wherein the barrier line divides the surface of the plastic part into an electroplating area and an electroless plating area; carrying out electroplating thin copper treatment on the electroplating area by adopting acid copper, and forming a thin copper plating layer in the electroplating area; performing chemical nickel stripping treatment on the surface of the plastic part subjected to the thin copper electroplating treatment; and after the thick copper plating treatment is carried out on the thin copper plating layer of the plastic part after the chemical nickel treatment, a thick copper plating layer is formed in the electroplating area. The electroplating method adopts acid copper to carry out electroplating thin copper treatment in an electroplating area on the surface of the plastic part, the acid copper can dissolve nickel overflowed in the chemical nickel plating process, the flatness of a nickel layer is improved, the side flatness of metal wiring in the later period is further improved, and the circuit electrical performance of the whole device is improved.)

1. A method for selectively plating a surface of a plastic article, the method comprising:

roughening the surface of the plastic part;

cleaning the plastic part after the roughening treatment, and then sequentially carrying out chemical roughening treatment and palladium precipitation degumming;

carrying out chemical nickel plating on the plastic part subjected to palladium precipitation and peptization;

carrying out laser on the surface of the plastic part after the chemical nickel plating to form a barrier line, wherein the barrier line divides the surface of the plastic part into an electroplating area and an electroless plating area;

adopting acid copper, and forming a thin copper plating layer in the electroplating area after performing thin copper electroplating treatment on the electroplating area of the plastic part;

performing chemical nickel stripping treatment on the surface of the plastic part subjected to the thin copper electroplating treatment;

and after the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment is subjected to thick copper plating treatment, a thick copper plating layer is formed in the plating area.

2. The method of claim 1, wherein roughening the surface of the plastic part comprises: and spraying the white corundum onto the surface of the plastic part by using sand blasting equipment, and performing mechanical roughening treatment.

3. The method of claim 1, wherein cleaning the roughened plastic part comprises: and (3) carrying out oil removal treatment on the plastic part by using ultrasonic waves and clear water.

4. The method of claim 1, wherein the steps of sequentially performing a chemical roughening treatment and a palladium gel deposition comprise:

performing weak acid micro-corrosion roughening treatment on the plastic part in a chemical pool containing chromic acid and sulfuric acid;

and exposing palladium particles on the surface of the plastic part subjected to weak acid micro-corrosion roughening treatment by using a degumming process, and performing palladium precipitation and degumming treatment.

5. The method of claim 1, wherein the plastic part is subjected to electroless nickel plating with a nickel layer thickness of 1 μm or less.

6. The method of claim 1, wherein the barrier line width is greater than or equal to 0.5 mm.

7. A method as claimed in claim 1, wherein the thin copper plating layer has a thickness of < 3 μm.

8. The method of claim 1, wherein the step of applying a chemical nickel stripping treatment to the surface of the plastic part after the thin copper plating treatment comprises:

and performing chemical nickel stripping treatment on the electroplating area and the non-electroplating area which are subjected to the acid copper electroplating treatment by adopting an etching method.

9. The method of claim 1, wherein the plating region forms a thick copper plating layer after performing a thick copper plating process on the thin copper plating layer of the degraded nickel-treated plastic part, the method comprising: and sequentially carrying out pre-copper plating, bright copper plating and coke copper plating on the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment, wherein a thick copper plating layer is formed in the electroplating area.

10. The method of claim 1, wherein after the step of applying a thick copper plating process to the thin copper plating layer of the degraded nickel-treated plastic part, the step of forming a thick copper plating layer in the plating region further comprises:

carrying out stannous electroplating treatment on the thick copper plating layer, wherein the thick copper plating layer forms a stannous electroplating layer;

and passivating the plastic part subjected to stannous electroplating treatment.

Technical Field

The invention relates to the technical field of plastic surface metallization, in particular to a plastic part surface selective electroplating method.

Background

The plastic metallization process is to manufacture or install a wire and a pattern with an electrical function on an injection molded plastic shell, so that the functions of electrical interconnection, supporting and protection of the common circuit board, the plastic shell and the supporting and protection of the common circuit board, shielding and antenna functions generated by the combination of a mechanical entity and the conductive pattern are integrated into a whole to form the three-dimensional molding interconnection device. The selective electroplating is to electroplate a layer of suitable metal, including tin, nickel, gold, silver and the like, only at the position where welding or surface contact is needed, and the precious metal can be electroplated independently and can be at any position on the surface of the plastic part.

The selective electroplating process widely applied at present forms a barrier line by laser etching a nickel layer on the surface of a plastic part, so that the surface of the plastic part is divided into an electroplating area and a non-electroplating area, and then an electroplating layer is electroplated in a mode of electroplating alkaline thick copper.

Disclosure of Invention

The embodiment of the invention provides a plastic part surface selective electroplating method, which aims to solve the problems that the prior plastic part selective electroplating process can generate an overflow plating phenomenon in the chemical nickel plating process, and the overflow plating tin can not only influence the side flatness of metal wires in the later period, but also can influence the circuit electrical performance of the whole device.

The embodiment of the application discloses a method for selectively electroplating the surface of a plastic part, which comprises the following steps:

roughening the surface of the plastic part;

cleaning the plastic part after the roughening treatment, and then sequentially carrying out chemical roughening treatment and palladium precipitation degumming;

carrying out chemical nickel plating on the plastic part subjected to palladium precipitation and peptization;

carrying out laser on the surface of the plastic part after the chemical nickel plating to form a barrier line, wherein the barrier line divides the surface of the plastic part into an electroplating area and an electroless plating area;

adopting acid copper, and forming a thin copper plating layer in the electroplating area after performing thin copper electroplating treatment on the electroplating area of the plastic part;

performing chemical nickel stripping treatment on the surface of the plastic part subjected to the thin copper electroplating treatment;

and after the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment is subjected to thick copper plating treatment, a thick copper plating layer is formed in the plating area.

Further, the roughening treatment of the surface of the plastic part comprises the following steps: and spraying the white corundum onto the surface of the plastic part by using sand blasting equipment, and performing mechanical roughening treatment.

Further, the cleaning and roughening treated plastic part comprises the following steps: and (3) carrying out oil removal treatment on the plastic part by using ultrasonic waves and clear water.

Further, the steps of sequentially carrying out chemical roughening treatment and palladium precipitation degumming comprise:

performing weak acid micro-corrosion roughening treatment on the plastic part in a chemical pool containing chromic acid and sulfuric acid;

and exposing palladium particles on the surface of the plastic part subjected to weak acid micro-corrosion roughening treatment by using a degumming process, and performing palladium precipitation and degumming treatment.

Furthermore, the thickness of a nickel layer of the plastic piece after palladium precipitation and glue dissolution is less than or equal to 1 mu m after chemical nickel plating.

Further, the blocking line width is more than or equal to 0.5 mm.

Further, the thickness of the thin copper plating layer is < 3 μm.

Further, the chemical nickel stripping treatment on the surface of the plastic part after the thin copper electroplating treatment comprises the following steps:

and performing chemical nickel stripping treatment on the electroplating area and the non-electroplating area which are subjected to the acid copper electroplating treatment by adopting an etching method.

Further, after a thick copper plating process is performed on the thin copper plating layer of the plastic part after the chemical nickel treatment, the thick copper plating layer is formed in the plating area, and the thick copper plating layer is formed by the plating area and comprises: and sequentially carrying out pre-copper plating, bright copper plating and coke copper plating on the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment, wherein a thick copper plating layer is formed in the electroplating area.

Further, after the thick copper plating treatment is performed on the thin copper plating layer of the plastic part after the chemical nickel treatment, the method further includes the following steps after the thick copper plating layer is formed in the electroplating area: carrying out stannous electroplating treatment on the thick copper plating layer, wherein the thick copper plating layer forms a stannous electroplating layer; and passivating the plastic part subjected to stannous electroplating treatment.

According to the technical scheme, the embodiment of the application shows the plastic part surface selective electroplating method, the electroplating method adopts acid copper to carry out electroplating thin copper treatment on an electroplating area on the surface of the plastic part, the acid copper can dissolve nickel overflowed in the chemical nickel plating process, the flatness of a nickel layer is improved, the side flatness of metal wiring in the later period is further improved, and the circuit electrical performance of the whole device is improved.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a flowchart illustrating a method for selectively plating a surface of a plastic part according to an embodiment of the present disclosure.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The existing selective electroplating process for plastic parts can generate an overflow plating phenomenon in the process of chemical nickel plating, and the overflow plating tin not only can influence the side flatness of metal wiring in the later period, but also can influence the circuit electrical performance of the whole device.

Referring to fig. 1, the present application illustrates a method for selectively plating a surface of a plastic part, the method comprising:

step S101, roughening the surface of the plastic part;

in the embodiment of the present application, the plastic part is formed by injection molding using enhanced polyphenylene sulfide (PPS + 30% glass fiber) (material No. ER008655 of Sabic corporation) containing metal particles to obtain a corresponding plastic part body. For the metallization of MID (injection molding connecting parts) materials, only the surface of plastic needs to be activated by laser, and then a metallization process of chemical plating is carried out. And the non-MID material needs to metalize the surface of the plastic, and palladium ions are deposited during surface treatment for the processes of thickness plating and electroplating. The enhanced polyphenylene sulfide (PPS + 30% glass fiber) product containing the metal particles has high yield and stable injection molding, and injection molding defects such as material shortage and the like are not easy to occur.

Further, the roughening treatment of the surface of the plastic part comprises the following steps: and spraying the white corundum onto the surface of the plastic part by using sand blasting equipment, and performing mechanical roughening treatment.

Specifically, the surface of the plastic part body is subjected to mechanical roughening treatment by adopting 60# to 80# white corundum, the surface roughness of the plastic part body is increased, the surface roughness of the plastic part meets the use requirements by adjusting the parameters of the sand blasting equipment, such as the jet speed, the air pressure and the like, the adhesive force of a subsequent plating layer is improved, the bad phenomena of peeling, falling and the like of the plating layer are prevented, and the ultrasonic cleaning is carried out to remove the residual sand blasting impurities on the surface.

Step S102, cleaning the plastic part after the roughening treatment, and then sequentially carrying out chemical roughening treatment and palladium precipitation and glue dissolution;

specifically, the plastic part after being cleaned and roughened comprises: and (3) carrying out oil removal treatment on the plastic part by using ultrasonic waves and clear water. And (3) deoiling the plastic part subjected to mechanical roughening, removing a surface release agent and a lubricant, and increasing the hydrophilicity of the surface of the matrix so as to ensure that the surface can be uniformly subjected to metal surface activation. The degreasing treatment can be mainly carried out in two ways: ultrasonic wave and clear water are used; the addition of the expanding agent on the basis of the mode a can introduce more pores and further increase the adhesion of the metal.

The method for sequentially carrying out chemical roughening treatment and palladium precipitation degumming comprises the following steps: performing weak acid micro-corrosion roughening treatment on the plastic part in a chemical pool containing chromic acid and sulfuric acid; and exposing palladium particles on the surface of the plastic part subjected to weak acid micro-corrosion roughening treatment by using a degumming process, and performing palladium precipitation and degumming treatment. Chemical coarsening is carried out, weak acid micro-corrosion coarsening is carried out in a chemical pool containing chromic acid and sulfuric acid, chromic acid neutralization is carried out, hexavalent chromium is reduced into monovalent chromium, and cleaning is carried out to remove chemical reagents remained on the surface.

The palladium deposition and dispergation can adsorb metal palladium on the surface of the plastic part, so that selective electroplating in subsequent steps is facilitated.

Step S103, performing chemical nickel plating on the plastic piece subjected to palladium precipitation and glue dissolution;

furthermore, the thickness of a nickel layer of the plastic piece subjected to palladium precipitation and glue dissolution is less than or equal to 1 mu m.

Step S104, performing laser on the surface of the plastic part after the chemical nickel plating to form a barrier line, wherein the barrier line divides the surface of the plastic part into an electroplating area and a non-electroplating area;

and carrying out laser etching on the position where the barrier line is to be formed, removing the chemical nickel layer on the position where the barrier line is to be formed, and forming the barrier line after removing. The barrier line width is at least 0.5mm and falls predominantly in the non-plated areas so as not to damage or reduce the predetermined shape or area of the plated areas.

During laser radium carving, can adopt and be furnished with manipulator 3D laser radium carving equipment, can accomplish a plurality of surfaces that need laser radium carving on the working of plastics, corner radium carving line can link and accomplish, the condition of dislocation can not appear.

Step S105, carrying out electroplating thin copper treatment on the electroplating area of the plastic part by using acid copper, and forming a thin copper plating layer on the electroplating area;

different from the prior art that alkaline pyrocopper electroplating is directly adopted, the embodiment of the application adopts acid copper to carry out electroplating thin copper treatment on the electroplating area of the plastic part, and the acid copper can also dissolve the residual nickel on the side surface in the electroplating process, so that the excessive plating is prevented, and the flatness of a nickel plating layer is improved firstly.

Further, in order to prevent the acid copper from excessively dissolving the nickel plating layer, the amount of the acid copper needs to be controlled while the thickness of the thin copper plating layer is < 3 μm.

S106, performing chemical nickel stripping treatment on the surface of the plastic part subjected to the thin copper electroplating treatment;

specifically, the chemical nickel stripping treatment of the surface of the plastic part after the thin copper electroplating treatment comprises the following steps: and performing chemical nickel stripping treatment on the electroplating area and the non-electroplating area which are subjected to the acid copper electroplating treatment by adopting an etching method.

Performing degradation chemical nickel treatment on the non-plating area to remove a chemical nickel layer on the non-plating area of the plastic piece, so that the surface of the non-plating area on the plastic piece is the surface of a raw material; the chemical nickel removing treatment adopts an etching mode, all surfaces of the plastic part are etched during etching, and the chemical nickel layer with the thickness of 1um is removed while the surface layer of the copper plating layer with the thickness of about 1um is removed.

And S107, after thick copper electroplating treatment is carried out on the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment, a thick copper plating layer is formed in the electroplating area.

Specifically, after the thick copper plating treatment is performed on the thin copper plating layer of the plastic part after the chemical nickel treatment, the thick copper plating layer is formed in the electroplating area, and the thick copper plating layer forming method includes: and sequentially carrying out pre-copper plating, bright copper plating and coke copper plating on the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment, wherein a thick copper plating layer is formed in the electroplating area. In this way the copper thickness is easier to control. The thickness of the copper layer formed in the electroplating area is more than or equal to 8 mu m.

Further, after the thick copper plating treatment is performed on the thin copper plating layer of the plastic part after the chemical nickel treatment, the method further includes the following steps after the thick copper plating layer is formed in the electroplating area: carrying out stannous electroplating treatment on the thick copper plating layer, wherein the thick copper plating layer forms a stannous electroplating layer; and passivating the plastic part treated by the stannous electroplating to form a passivation film on the stannous electroplating for tin protection.

Finally, the plastic part after the selective electroplating process is dried and secondarily dried, so that the metal coating and the plastic part are more tightly combined.

The embodiment of the application avoids the defect that the side flatness of the metal wiring is poor easily caused by electroplating alkaline thick copper in the selective electroplating process, divides the surface of the plastic part into an electroplating area and a non-electroplating area, and adopts an electroplating method combining thin-plated acid copper and thick copper on the electroplating area, so that the problem that the side flatness of the metal wiring is poor easily caused by electroplating alkaline thick copper in the selective electroplating process is solved, and the selective electroplating process has a wide application prospect.

In view of the above technical solutions, embodiments of the present application show a method for selectively electroplating a surface of a plastic part, the method including: roughening the surface of the plastic part; cleaning the plastic part after the roughening treatment, and then sequentially carrying out chemical roughening treatment and palladium precipitation degumming; carrying out chemical nickel plating on the plastic part subjected to palladium precipitation and peptization; carrying out laser on the surface of the plastic part after the chemical nickel plating to form a barrier line, wherein the barrier line divides the surface of the plastic part into an electroplating area and an electroless plating area; adopting acid copper, and forming a thin copper plating layer in the electroplating area after performing thin copper electroplating treatment on the electroplating area of the plastic part; performing chemical nickel stripping treatment on the surface of the plastic part subjected to the thin copper electroplating treatment; and after the thin copper plating layer of the plastic part subjected to the chemical nickel degradation treatment is subjected to thick copper plating treatment, a thick copper plating layer is formed in the plating area. According to the electroplating method, the acid copper is adopted to carry out electroplating thin copper treatment in an electroplating area on the surface of the plastic part, the acid copper can dissolve nickel overflowed in the chemical nickel plating process, the flatness of a nickel layer is improved, the side flatness of metal wiring in the later period is further improved, and the circuit electrical performance of the whole device is improved.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

It will be understood that the present application is not limited to the precise procedures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.