High-impact polystyrene is a polystyrene resin used in lower heat applications. As its name suggests, Hips has high impact strength and good dimensional stability. The hips are lightweight to thermoform and can be printed using Digital, Screen, Flexo and Litho inks.
The hips are naturally white and have a matte finish, and while not naturally translucent, the hips can be easily painted and glued for a great aesthetic. A good example of food packaging Hips are cups of yogurt. Some HIPS classes are designed to be extremely resistant to specific end use, such as in refrigeration chimneys, toilets and tanks, or equipment available that require high resistance to environmental stress.
GPPS has a glass-like clarity, which makes it popular in transparent food packaging, and can be easily molded into various shapes. Because of this, GPPS is also a popular choice for plastic toy applications. GPPS is often used in refrigerator trays, boxes, cosmetics packs and CD cases. The GPPS is fragile and has low impact strength as well as less dimensional stability than the Hips. Unlike the Hips, the GPPS comes in either a light blue lip or clear water tinge.
While both GPPS and HIPS are considered low cost, polystyrene (GPPS) is the most effective of both polystyrene.