for use on open-grain timbers, as they can quickly fill wood grain, with a high-build film thickness per coat. It can be used for fashionable dresses, but it is most admired for its ability to resist wrinkling and shrinking while washing the product. Its toughness makes it a frequent choice for children's wear. Polyester is often blended with other fibres like cotton to get the desirable properties of both materials. Cured polyesters can be sanded and polished to a high-gloss, durable finish. Production Basics Polyethylene terephthalate, the polyester with the greatest market share, is a synthetic polymer made of purified terephthalic acid (PTA) or its dimethyl ester dimethyl terephthalate (DMT) and monoethylene glycol (MEG). With 18% market share of all plastic materials produced, it ranges third after polyethylene (33.5%) and polypropylene (19.5%) and is counted as commodity plastic. There are several reasons for the importance of polyethylene terephthalate: The relatively easy accessible raw materials PTA or DMT and MEG The very well understood and described simple chemical process of its synthesis The low toxicity level of all raw materials and side products during production and processing The possibility to produce PET in a closed loop at low emissions to the environment The outstanding mechanical and chemical properties The recyclability The wide variety of intermediate and final products. In the following table, the estimated world polyester production is shown. Main applications are textile polyester, bottle polyester resin, film polyester mainly for packaging and specialty polyesters for engineering plastics. Polyester processing After the first stage of polymer production in the melt phase, the product stream divides into two different application areas which are mainly textile applications and packaging applications. In the following table, the main applications of textile and packaging of polyester are listed. Abbreviations: PSF Polyester-staple fiber POY Partially oriented yarn DTY Drawn textured yarn FDY Fully drawn yarn CSD Carbonated soft drink A-PET Amorphous polyethylene terephthalate film BO-PET Biaxial-oriented polyethylene terephthalate film A comparable small market segment (much less than 1 million tonnes/year) of polyester is used to produce engineering plastics and masterbatch. In order to produce the polyester melt with a high efficiency, high-output processing steps like staple fiber (50–300 tonnes/day per spinning line) or POY /FDY (up to 600 tonnes/day split into about 10 spinning machines) are meanwhile more and more vertically integrated direct processes. This means the polymer melt is directly converted into the textile fibers or