Several copper suppliers have decided to switch part or their entire capacity to the production of Battery Foils for Electrical Cars. (There is a particularly strong demand in China). As a result, there is a shortage of standard foils for the electronics market. This situation is unlikely to change over the next 6 months.
In addition, during the third quarter, a number of companies have been trying to raise their prices as many report unsustainable margins for 2016. With the advent of small feature sizes and quality requirements in many of the end markets going forward, PCB companies are going to have to invest even more in up to date equipment and will need a sufficient margin to re-invest.
This may well be beyond some manufacturers in 2017. Therefore much of the increased demand value in 2017 is likely to come mainly from this potential price increase, rather than any uptick in underlying demand.