Abstract A method and apparatus are disclosed for the production of a novel industrial polyester filament yarn of improved uniformity wherein a plurality of filaments are melt-spun into a heated zone coupled with controlled cooling. The yarn produced has improved long and short term Uster uniformity and improved uniformity of physical properties, particularly breaking strength, as shown by a reduced standard deviation of breaking strength. The yarn is produced by melt spinning into a heated zone which maintains the filaments molten for intervals below the spinneret face and subsequently quenching the filaments with a radial outflow of cooling gases, thereby producing a low birefringence yarn which is capable of being drawn at high draw ratios to high tenacities.
A heavy denier melt spun polyester filament yarn having a tenacity of more than 7.0 grams per denier, a long and short term percent Uster of less than 1.5, a tensile factor of more than 28, and a breaking strength standard deviation of less than 0.20 grams per denier as measured in yarns across a beam.
Claim 2
Dependent Claim
56 words
A heavy denier melt spun polyester filament yarn having a tenacity of more than 7.0 grams per denier, a long and short term percent Uster of less than 1.5, a tensile factor of more than 28, and a breaking strength standard deviation of less than 0.20 grams per denier as measured in yarns across a beam.
Claim 3
Dependent Claim
56 words
A HEAVY DENIER MELT SPUN POLYESTER FILAMENT YARN HAVING A TENACITY OF MORE THAN 7.0 GRAMS PER DENIER, A LONG AND SHORT TERM PERCENT USTER OF LESS THAN 1.5 A TENSILE FACTOR OF MORE THAN 28, AND A BREAKING STRENGTH STANDARD DEVIATION OF LESS THAN 0.20 GRAMS PER DENIER AS MEASURED IN YARNS ACROSS A BEAM.
Claim 4
Dependent Claim
56 words
A HEAVY DENIER MELT SPUN POLYESTER FILAMENT YARN HAVING A TENACITY OF MORE THAN 7.0 GRAMS PER DENIER, A LONG AND SHORT TERM PERCENT USTER OF LESS THAN 1.5 A TENSILE FACTOR OF MORE THAN 28, AND A BREAKING STRENGTH STANDARD DEVIATION OF LESS THAN 0.20 GRAMS PER DENIER AS MEASURED IN YARNS ACROSS A BEAM.
Claim 5
Dependent Claim
23 words
The heavy denier yarn of claim 1 whereiN the polyester is polyethylene terephthalate and the tenacity is greater than 8.0 grams per denier.
Claim 6
Dependent Claim
18 words
The heavy denier polyester yarn of claim 1 wherein the long term percent Uster is less than 1.0.
Claim 7
Dependent Claim
41 words
The heavy denier polyester yarn of claim 1 wherein the denier per filament is 3 to 20, the total denier is 500 to 5,000, the tenacity is 8 to 11 grams per denier and the tensile factor is more than 30.