"The ClearTint technology is showing how beverage caps, traditionally considered a commodity element, can become an added-value part of bottle aesthetics by replicating either beverage colour or brand colour in transparent PP as an enhancement of consumer appeal and brand image," the company said in a press release.
One customer, Bormioli Rocco has created a range translucent screw closures for mineral water, soft drinks and other bottled beverages. Their design includesthe use of ClearTint colourants.
Bottle caps are normally made from aluminium or PP with solid pigments. In addition, PP provides mechanical and safety advantages by protecting the mouth of the bottle.
"Polypropylene absorbs every accidental bump on the bottle cap before the product arrives at the point of sale, protecting the glass and preserving a high quality appearance," Milliken said. "Customers who use aluminium caps and returnable bottles frequently have many breakages."
The company produces the ClearTint coloured caps at its plant in Rivazzano in Italy's Pavia province, using compression moulding.
Milliken's ClearTint colourants are migration-resistant, non-toxic, non-abrasive and heat-resistant. The company said it has the ability to prepare a hugepalette of clear colours, many of which are compliant with US regulations for food contact applications.
ClearTint coloured products can be reground and recycled.
Milliken is one of the world's largest privately held textile and chemical corporations. It makes additives for plastics, including Millad 3988 clarifyingagent, Hyperform nucleating agents.