Plastic Jars
Plastic jars are 3-dimensional containers that have an opening at the top that is greater than 50% the jar's diameter. They mostly have lids and are used in the food, cosmetic, pharmaceutical and medical industries to contain many different commercial products that are often in liquid, paste, gel and powder form. Products like peanut butter, mayonnaise, cosmetic products like concealer and lip balm all use plastic jars as packaging. Although the top may be slightly tapered, jars differ from plastic bottles in that they don't have a neck but rather a larger opening. They differ from jugs because they aren't made with handles. Plastic jars are almost always produced with removable lids. The top of the jar often has male threading, while the jar interior has female threading, creating an air-tight twist-off seal.
Plastic jars are manufactured through the blow molding process, where molten plastic is inflated inside a mold and left to cool in the desired shape. This container producing method is fast, inexpensive and can produce transparent, opaque and solid colored jars in high numbers. Plastic resins like polyethylene, polystyrene and polyethylene teraphthalate are used as the materials which produce square, round, hexagonal and straight-sided jars. They can range in size anywhere from .25 ounces to 1 gallon. Using plastic to make jars has become a popular alternative to glass because it won't shatter when dropped, it's stronger and less expensive to produce.