An airbag housing for a front seat passenger airbag module includes high side walls having a curved profile when viewed from above. More specifically this process relates to a process to produce polyethylene terephthalate where terephthalic acid and ethylene oxide are reacted to form a partially esterified terephthalic acid product and then the partially esterified product is further reacted with ethylene glycol to produce polyethylene terephthalate. 9, for use in oxidative dyeing of hair comprising 0. Preferred hydrophilic polymers include hydroxypropyl cellulose and hydroxypropyl methylcellulose. In one embodiment, an oxide cap layer is formed on the phosphoric acid layer to form a capped substrate.