In 1987 Shepherd, along with almost every other packager providing blister sealing was using PVC blisters. Today, it’s hard to find PVC on the retail shelves, not that you could easily identify it from what is used today, which is predominantly recycled PET (RPET).
Twenty five years ago large corporations like Johnson and Johnson were telling us that they wanted an alternative to PVC for their blister packaging because of the issues related to its chlorine content and more recently, the problems it causes in the recycling streams. Back then we started supplying PET which was more expensive than PVC and which was quite difficult to heat seal to blister cards. At the same time the environmental issues in the packaging industries were becoming more of a hot topic, especially in Europe and the push was on to recycle PET bottles. Within a few years RPET became more available however heat sealing it to a coated card was still difficult. The card suppliers blamed the RPET suppliers and visa versa. At Shepherd we were always in the middle and we became experts in adjusting the sealing equipment to find just the right seal temperature, pressure and dwell time that would work for the combination of card stock, plastic and heat seal coating.Although our business has taken us into many different markets and heat seal blisters are probably less than 5% of our total business today, the blister pack is still a secure form of packaging providing an attractive an sturdy way to display and market smaller products. It requires a heat sealing machine but once that is set up correctly it is an efficient method of getting the product to market.Improved heat seal coatings and seal technology has made RPET the material of choice over PVC for blister packaging today.