Selecting the appropriate material is critical for both branding and functionality. PP (Polypropylene) is the industry standard for heat-sealing with film, as it is heat-resistant (up to 120°C) and flexible. PET (Polyethylene Terephthalate) offers superior clarity and gloss, making it ideal for cold 'Instagrammable' drinks, but it cannot be heat-sealed and requires matching lids. For eco-conscious markets, PLA (Polylactic Acid) or Aqueous-coated paper cups are essential to meet plastic-free regulations, though they come at a 20-30% higher cost premium.