一. Glass Types and General Properties Advantages as a packaging material: ⚫ inert to most chemicals ⚫ perfect foods container. ⚫ impermeability ⚫ clarity ⚫ perceived image ⚫ rigidity ⚫ stable at high temperatures Disadvantages : breakability; high weight; high energy costs .一. Glass Types and General Properties Advantages as a packaging material: ⚫ inert to most chemicals ⚫ perfect foods container. ⚫ impermeability ⚫ clarity ⚫ perceived image ⚫ rigidity ⚫ stable at high temperatures Disadvantages : breakability; high weight; high energy costs