Most bottle caps for single-use bottles are made from high-density polyethylene (HDPE). When an HDPE cap is tightened on a bottle, plastic from the cap’s “ceiling” squishes against the lip ...

John Sugden, Dow application technology leader for rigid packaging, talked about bimodal HDPE for use in aseptic and hot-fill bottles. In hot fill, the plastic bottle expands after filling.

Soon to be gone are the days of picking up a blue cap for your whole milk ... So what’s wrong with coloured milk bottle caps and why are we seeing an increase in white or clear versions?

Colour-coded bottle ... white in 331 Waitrose shops. It was done with the help of dairy company Muller, which purchases a fifth of all milk produced on farms across the UK. The red cap is ...