Page 31 - CFCM Sept-Oct-2020_Neat

low level of acceptance in those days. The blend contains 40 to 60 percent this helps in promoting a more uni-
However, the adhesive properties of of ABS, while the remaining is made form absorption during the activa-
plastics were enhanced through the up of PC. This mixture offers high duc- tion stage.
implementation of a chromic acid- tility and strength, and can be used in • Neutralizing – Neutralizers such
based etchant that, to cite one extreme temperatures. as sodium bisulfite can help
example, was used for the surface ensure the elimination of any
treatment on acrylonitrile-butadiene- The typical plating on plastic process excess etchant.
styrene (ABS), a thermoplastic terpoly- involves these steps: • Pre-activating – Pre-activator
mer. The process found usage first in helps in facilitating absorption
the automotive industry in the 1970s, • Cleaning – Requires a mild alka- during the activation stage of the
and a variety of areas such as plumb- line, or in certain instances, a plating on plastic process. They
ing, electronics and household product chromic acid solution. work well with polypropylene or
manufacturers adopted it in the 70s • Pre-dipping – Helps improve the polyphenylene oxide.
and 80s. surface of poorly molded, highly • Activating – Involves the usage of
Toronto-based Leader Plating on stressed parts. Also makes it easier low-concentration precious metal
Plastic is a family-run business that for etchant to react and attack the liquid activator, which serves as a
has been plating bright chrome on surface. catalyst during plating. Typical
plastic since 1979. It began with • Etching – Etchants generally con- metals found in activators include
appliances for companies like Inglis sist of sulfuric acid or chromium platinum, gold and palladium.
and Whirpool. trioxide solutions, which help to • Accelerating – Accelerators
Now Leader’s clients include a long increase the substrate surface, thus removes excess stannous hydroxide
list of major automotive manufacturers enhancing liquid absorption. from the part, and also prevents
where chrome is becoming pervasive. • Conditioning – An optional step skip plating occurrence during the
“Motorcycles love chrome,” says Rob in the plating on plastic process, plating on plastics process.
Corazza, Plant Manager.
The resins are important. A variety
of resins are used for plating on plastic
applications, although 90 percent of
these applications are ABS, the Grand NEW
View report says. It has an acryloni-
trile-styrene matrix which is evenly Coating Thickness Gages
distributed with butadiene rubber,
which leads to effective plating. The 2 models
butadiene is etched out from the ma- Ferrous for Steel
trix, leaving microscopic holes that are Combo for All Metals
utilized as bonding sites by the plate.
Other factors that have encouraged the Fast, repeatable measurements
large scale use of ABS are the ease of (60+ readings per minute)
molding, high metallic adhesion, Ready to measure—no adjustment
affordability and low coefficient of required for most applications
thermal expansion. Onscreen averaging for up to 99 readings
Other resins that may be used for Strong, wear-resistant, ruby-tipped probe
the plating on plastic process include Two year warranty on gage body AND probe
PEI (polyetherimide), PBT (polybuty-
lene terephthalate), LCP (liquid crys-
tal polymer), PEEK (polyether ether www.defelsko.com
ketone), and nylon/polyamide,
among others. 1-800-448-3835
PEEK and polypropylene can only simply
be plated in a blended form, says
Grand View, adding that ABS polycar- measures
bonate (ABS/PC) is expected to wit-
ness solid demand in the plating on DeFelsko Corporation Ogdensburg, New York USA
Tel: +1-315-393-4450 Email: techsale@defelsko.com
plastics market in the coming years.
www.cfcm.ca CAnADIAn FInISHInG & COATInGS MAnuFACTuRInG 31