Method to increase the heat deflection temperature of amorphous polyethylene terephthalate
AssigneeThe Mead Corporation
InventorDavid R. Allan
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Abstract
The heat deflection temperature of amorphous thermoformed polyethylene terephthalate is increased by removing absorbed and/or adsorbed water therefrom, as by heating in an oven, or by desiccation. Following drying, the material is kept in a desiccated storage vessel until time of use.
Claims9
Method to increase the heat deflection temperature of amorphous polyethylene terephthalate by removing water therefrom.
Method to increase the heat deflection temperature of amorphous polyethylene terephthalate cups from about 155.degree. F. to 175.degree. F. by heating said cups in an oven at a temperature of 145.degree. F. to 150.degree. F. for four hours to remove water therefrom and thereafter storing said cups in a closed desiccated vessel.
Dependencies are inferred from the claim text.