Metallizing of ABS synthetic products and spare parts through the usage of surface treatments such as copper plating, nickel plating, chrome plating and gold plating.

Also for metallizing of synthetic products you can contact Multinal Group. Our subsidiary in Coevorden has been specialized in metallizing of synthetic products for many years, in particular you have to think about ABS-synthetics and ABS-blends. The purpose of this surface treatment is increasing the decorative and functional properties of the product.

We already have clients from several sectors. It concerns a great variety of products, for instance industrial products (reflection, shielding), but also household products and sanitary parts.

 

Read more about the metallizing of ABS/ABS-blends synthetic products.

The advantages of POP:

  • High decorative value
  • Higher resistance
  • Scratch resistant
  • Increased strength
  • Decrease of impact strength
  • Deformation resistance increases
  • Anti-static effect, dust repellent
  • Absorption and reflection of radiation
  • Corrosive resistance

The process

Galvanizing of plastics or Plating on Plastic (POP) is a relatively new technology. Plating of thin and adhering galvanic deposits on plastic substrates is possible only since approximately 1960.

The conventional POP technology is based on ABS and ABS-PC blends.

ABS is a so called co-polymer of Acrylonitril Butadiene Styrene. The composition is approximately 5 to 30% butadiene, styrene approximately 50%, the rest is acrylonitril . Butadiene is the substance which forms -mixed with a little bit of carbon and sulfur- the base for rubber. The two other substances create a firm material. The butadiene, in the form of microscopic spheres, is mixed in the ABS matrix. By means of a strong oxidizing agent, small cavities are created in the surface of the ABS, by etching out the soft butadiene spheres. The remaining (hard) material is attacked at a much lower rate. Which remains is a smooth surface with microscopic cavities and polar groups attached to the hard plastic.

Applying the activator

The next step is to apply the activator; a noble metal (palladium) which attaches to the polar groups on the surface. The finely distributed noble metal is the starter material for the auto catalytic nickel or electroless nickel process to deposit a thin layer of nickel. This nickel deposit covers the surface and fill the etched out cavities of the ABS with nickel. The deposited nickel layer adheres both chemical (to the polar groups) and mechanical (in the etched out cavities); the so called push-button effect. To create a firm and decorative surface, after activation by means of a nickel strike, consecutive layers of copper, nickel and chrome are galvanically deposited.

The thicknesses of the layers are:

  • e’less nickel  : 0,1 – 0,5 µm
  • nickel strike  : 0,5 – 2,0 µm
  • copper          : 15 -25 µm
  • nickel            : 8 – 15 µm
  • chrome         : 0,1 – 0,6 µm

The thickness of the deposited metal layers have a technical minimum and a economical maximum. In other words, too thin layers deteriorate the quality of the product. Thick layers make a very beautiful and strong finish, though at certain thicknesses, the technical is not worth the cost, which would make the final product too expensive to sell.

Problems in POP are often also caused by the choice of substrate material: the ABS or ABS-PC blend. The size, concentration or distribution of the butadiene does not suite the requirements for POP. Processing parameters, during the molding process, can also cause major problems in the direction of adhesion or even covering power. In those cases internal stress in the substrate, recesses, in the products, uncovered areas, decorative defects or cracks after thermal load may occur.

Major points of attention for metallizing ABS/ABS-blends synthetics

  • Any hollow areas in objects should be capable of being rinsed or welded liquid-proof so that bath liquids drain easily and cannot remain behind;
  • There should be rinsing holes present on either side and on the ends of the material. This will reduce the chances of the bath liquid remaining behind;
  • Do products need special attention because they are vulnerable or expensive or have special assembly requirements after metallizing? Let us know this;
  • We recommend that you always supply a technical materials sheet with your shipment;
  • Always report any differences in material in advance. This is certainly necessary if such differences are not visible. This could have unnecessary, unwanted consequences for the end result;
  • The quality of the basic material that you deliver plays an important role in the ultimate end result. When in doubt, we will contact you, to safeguard your and our quality standards. Multinal expects 100% correct, blank materials are brought in. This means that any injection molding errors already should have been removed before delivery;
  • The machining operation after metallizing could have major (negative) consequences for your product. We therefore recommend that you carry out the machining operation in advance of the surface treatment.

Before and after the surface treatment

On the pictures below you can see both the products before the treatment as ABS base material and the final result, with both glossy and matte finish.

 

 

ABS-en-mat-verchroomd-onderdeel1   ABS-en-glans-verchroomd onderdeel   ABS-en-mat-verchroomd-onderdeel2

 

ABS-behandelde-onderdelen   ABS-chroom-goud   ABS-en-mat-verchroomd-onderdeel4