Copolyesters of ethylene 2,6-naphthalene dicarboxylate and halogenated comonomers
AssigneeAvtex Fibers Inc.
InventorWilliam N. Knopka
Life of this patent
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Abstract
A flame-retardant filament-forming copolymer of at least 75 mol % of ethylene-2,6-naphthalene dicarboxylate units and at least 3 mol % up to 25 mol % of randomly copolymerized esters units having bromine or chlorine chemically united with either the diacid residue or both the diacid residue and the diol residue of said ester units. In addition, fibers of the above flame-retardant copolyester resin and flame-retardant cellulosic fibers are blended together to provide flame-retardant yarns and fabrics of excellent physical properties.
Claims9
A linear, filament-forming, random copolyester resin of at least 75 mol % of ethylene-2,6-naphthalene dicarboxylate units and at least 3 mol % up to 25 mol % of a copolymerized halogenated ester unit having bromine or chlorine chemically united with either the dicarboxylic acid residue of said ester unit or both the diacid residue and the diol residue of said ester unit in an amount sufficient to provide at least 3.5% of the halogen, based on the weight of the copolyester.
Dependencies are inferred from the claim text.