Thermoform trays

A well-established application for extruded unreinforced PCT (copolymerized with isophthalate) is crystallized, thermoformed trays for foods. Crystallized PET is widely used for this application, but where higher-temperature performance is needed the PCT-based polymer may be chosen. Such trays are formed from extruded sheet, using a hot mold to promote crystallization. Isophthalate-modified PCT polymers are approved by the Food and Drug Administration for high-temperature food contact use. 

The main markets for PLA are thermoformed trays and containers for food packaging and food service applications. Other developing areas include films and labels, injection stretch blow moulded bottles and jars, specialty cards and fibres. 

Rigid packaging applications include thermoformed trays and containers for packaging fresh food and convenience food. 

Thermoforming For thermoforming applications, Mater-Bi is being used to manufacture nontransparent, hard, thermoformed trays for packaging fresh food. 

EarthShell also supplies materials for manufacture of thermoformed trays for fresh produce and meat, as well as disposable plates, bowls, and cups. In these products, polyester is used as a moisture-barrier over a rigid substrate made of a low-cost natural composite supplied by EarthShell and Apack AG, Germany. The EarthShell composite consists of cellulose from paper waste, starch from potato waste, ground limestone, and water. Apack dispenses with the limestone but adds a polymeric ingredient. Both composites are foamed and formed with special equipment in a process comparable to making waffles. 

Thermoformed trays and containers for food packaging and food service applications. 

PLA is also used for thermoformed trays and containers. Injection stretch blow moulded bottles and jars for short-shelf-life applications that use cold-filling techniques for contents such as still water, fresh juices, dairy beverages and edible oil is also a potentially interesting market for PLA. 

Autobar has worked with Italian supermarket chain, Iper, on the manufacture of PLA thermoformed trays and containers for fresh foods in place of polypropylene. The packaging consists of 12 sizes, categorised as small , medium , large and maxi , that offer a range of dimensions. 

OPS is commercially available in 0.13-0.76 mm gauge. The tenter frame process for manufacturing OPS is the most common process used today. A typical tenter frame process is shown in Figure 11.1. Tentered OPS is distinguished from polystyrene blown films (which are also biaxially oriented) in that the tenter frame process can produce heavier gauge films than the blown-film process. Blown films (0.025-0.13 mm) are used primarily in window envelopes, lamination, and printed applications tentered OPS is typically used in thermoformed trays, lids, and containers for rigid food packaging applications. 

Plan tic Technologies Ltd. httD //www.Dlantic.com.au Plantic Thermoplastic com starch polymer Thermoformed trays... 

In using a tray for a sterile medical device, in order to perform the most basic protection function, the tray must be sealed to prevent loss of sterility. This is accomplished by using a lidding material that is sealed around the flange area of the tray. Until the advent of Tyvek into the market, it was difficult to provide lidding material that would provide a means for terminal sterilization using the common sterilization methods of the day. However, Tyvek has allowed widespread use of thermoform trays for many applications. 

This system is ideal for thermoformed trays with porous lids and flexible pouches with one porous side. The test has been shown to detect leaks as small as 0.002 in. Guidmt and Medtronic have demonstrated the reliability of detecting leaks in blind tests and have quantified 100 percent of the purposely manufactured leaks in thermoformed trays (Hacked, 1996). In addition, there were no false positive readings in any of the unaltered packages. 

Many medical products have moved from rigid to flexible packages. Kendall Health Care switched from a thermoformed tray to a flexible pouch for a urine collection assembly used in hospitals and achieved a waste volume reduction of about 50%. Medchem changed hemostat packaging from a glass jar inside a foil-lined container to a plastic tray in a pouch and achieved an 80% reduction in packaging by weight [13]. 

It is an addition polymer of styrene. It is clear and has a high tensile strength. PS alone is brittle, bnt can be blended or generally biaxially oriented to achieve required properties. It has high gas and moisture permeabihty and hence can be used for highly respiring commodities. It may be oriented to improve the barrier properties. In heavier gauges, PS is used for transparent thermoformed trays. 

Attention has been paid to the possible use of multilayer coextrusion of engineering resins for dual ovenable containers, as multilayer packaging could increase shelf stability and thus eliminate the need for freezing or refrigeration. One multilayer combination in commercial use is a sheet of Lexan polycarbonate sandwiched between layers of Ultem polyetherimide. Thermoformed trays of this material are reported to have better break resistance at lower temperatures and higher stiffness at temperatures up to 232°C, as compared to CPET. They are also insert, compatible with polyester lidding materials, and have lower oxygen permeability than PET materials. 

Very recently Plantic Technologies Ltd produced soluble Plantic thermoformed trays for confectionery packaging [http //www.plantic.com.au]. Plantic material is based on thermoplastic com starch polymer and is processible on standard polymer processing equipment. 

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