Carbonated soft drinks (CSD) are soft drinks with a certain level of carbonation (between 2 vol. to 4.5 vol. of CO2). The resins in PET bottles used to package CSD must demonstrate very specific qualities. The material must be extremely strong in order to contain the internal pressures of CO2 without becoming distorted or expanding. Such strength is obtained by using a resin with high intrinsic viscosity and lower copolymer levels. The other main requirements of a CSD container are burst and drop resistance, a shape and design which resists high internal pressure and low bottle weight balanced with stability.
Soft drinks with a certain level of carbonation (from 2 vol. to 4.5 vol. of CO2).
There are no special requirements for bottling carbonated soft drinks. Nevertheless, it is important to optimize the manufacturing process of a CSD bottle in order to achieve physical and mechanical characteristics required by the client.
The main requirements of a carbonated soft drink container are:
- Preservation of CO2 level inside the packaging (This is important especially for containers of small size)
- Reduction of bottle expansion due to internal pressure (Shape keeping)
- Burst and drop resistance
- Shape and bottom designed to resist high internal pressure (creep and burst resistance)
- Reduced bottle weight while assuring bottle stability