Process for producing polyester composition
AssigneeMitsubishi Polyester Film GmbH
InventorTakatoshi Miki
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Abstract
A process for producing a polyester composition, comprising polyester and a metal salt of an aliphatic carboxylic acid, whereby a metal salt and polyester are fed together into a vented extruder as a raw material. The raw material has a specific resistance of not less than 1×107 Ω·cm upon melting and a metal atom concentration of 0.5 to 1,000 ppm based on the polyester composition. This process is industrially useful for producing a polyester composition which can be used to form sheets using an electrostatic pining method.
Claims14
A process for producing a polyester composition comprising polyester and a metal salt of aliphatic carboxylic acid, said process comprising:
- providing a regenerating apparatus comprising a pulverizer and a vented single screw extruder connected to said pulverizer;
- feeding recovered polyester having a specific resistance of not less than 1×107 Ω·cm upon melting, to said pulverizer;
- pulverizing said recovered polyester in said pulverizer;
- and
- adding said metal salt to said pulverized recovered polyester in such an amount that the concentration of metal atom based on said polyester composition is 0.5 to 1,000 ppm, before said pulverized recovered polyester reaches said vented single screw extruder.
A process for producing a polyester composition comprising polyester and a metal salt of aliphatic carboxylic acid, said process comprising:
- providing a regenerating apparatus comprising a pulverizer and a single screw extruder connected to said pulverizer, said single screw extruder having a vent port and a powder feed port sequentially arranged along the extruding direction thereof;
- feeding recovered polyester having a specific resistance of not less than 1×107 Ω·cm upon melting, to said pulverizer;
- pulverizing said recovered polyester in said pulverizer;
- and
- feeding said metal salt through said powder feed port into said single screw extruder to add said metal salt to said pulverized recovered polyester in such an amount that the concentration of metal atom based on said polyester composition is 0.5 to 1,000 ppm.
A process for producing a polyester composition comprising polyester and a metal salt of aliphatic carboxylic acid, said process comprising:
- providing a regenerating apparatus comprising a pulverizer and a single screw extruder connected to said pulverizer, said single screw extruder having a vent port and a powder feed port sequentially arranged along the extruding direction thereof;
- feeding recovered polyester having a specific resistance of not less than 1×107 Ω·cm upon melting, to said pulverizer;
- pulverizing said recovered polyester in said pulverizer;
- and
- feeding said metal salt and polyester having a bulk density of 0.05 to 1.0 g/cm3 through said powder feed port into said single screw extruder to add said metal salt and said polyester to said pulverized recovered polyester.
Dependencies are inferred from the claim text.