In addition, the insertion of the PS symbol indicates that it is made of polystyrene and such a container is in contact with hot and greasy foods due to the release of styrene carcinogenic monomer; therefore, these containers should not be used for food and hot drinks And fatty acids, and are used only for soft drinks and cold-fat foods. These containers are available in three types of polystyrene foam (EPS), expanded polystyrene (HIPS) and ordinary polystyrene containers (GPPS).

It should be noted that conventional plastic injection machines are used to produce disposable forks & spoons & knives and thick disposable containers such as trays, dessert and ice cream containers and so forth. The only difference is the changeability of molds by which the containers can be produced in different models and cavities (number of products in each press) in accordance with customers’ order.

This process is especially effective for producing food containers with wide mouths, such as tubs, vials, jars, pots and trays. The plastic used is thin and light to hold the overall product easily. Yet it&#;s also durable, flexible and resistant to tears, chemical spills and other damage that can spoil the food inside. The process is relatively easy and simple. This allows for faster processing times and larger scale production for larger packaging projects.

Polypropylene (PP) is the main consuming material of forming machines. These machines are composed of two parts: sheet making and pressing (containers production). Therefore, in addition to selling the final product of these machines, the produced sheets could be used in different industries. Since propylene is flexible and is not harmful to human body, disposable glasses are currently made by thermo-forming machines.

Generally, all disposable containers are divided in two categories: semi-forming (PS) and thermo-forming (PP). They differ in consuming materials, production stages and price. In all disposable container production machines the raw material melt and then are formed into sheets and get different shapes via pressing and shaping processes. In semi-forming machines, all above-mentioned stages are integrated and the consuming material is polystyrene (PS). These machines generally produce fragile containers. However, these machines produce majority of disposable containers, including bowls, cups, dishes and mushroom container. The reason is the low price of semi-forming machines compared to forming-machines. Since the containers are fragile and harmful, especially in dealing with hot, these machines are not recommended for producing disposable glasses.