String of a vinylidene fluoride synthetic resin composition
AssigneeDynamit Nobel Aktiengesellschaft
InventorsGunther Tappe, Bertram Gasper, Herbert Laubenberger, Richard Weiss
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Abstract
A string for the stringing of rackets, bows, musical instruments and the like has a thread-like structure comprising at least one monofil of a synthetic resin mixture containing 99-86% by weight of polyvinylidene fluoride and 1-14% by weight of at least one polyacrylate. The monofil is melt-extruded and is stretch-oriented to impart improved elasticity thereto.
Claims13
A string for the stringing of rackets, bows, musical instruments and the like, comprising a thread-like structure having at least one monofil of a synthetic resin mixture containing 99-86% by weight of polyvinylidene fluoride and 1-14% by weight of at least one polyacrylate selected from the group consisting of a polyacrylate homopolymer, a copolymer of vinylidene fluoride monomer with at least one acrylate monomer, and mixtures thereof, which is stretch-oriented to impart improved elasticity thereto;
- said monofil exhibiting an attenuation between -20.degree. C. and 30.degree. C. that closely approaches that of natural gut string.
A process for the production of a string of a synthetic resin based on polyvinylidene fluoride which comprises extruding a synthetic resin rod from a melt consisting essentially of a synthetic resin mixture containing 99-86% by weight of polyvinylidene fluoride and 1-14% by weight of at least one polyacrylate selected from the group consisting of a polyacrylate homopolymer, a copolymer of vinylidene fluoride monomer with at least one acrylate monomer, and mixtures thereof at a melt temperature of 250.degree.-350.degree. C., cooling the resulting rod to a temperature of 60.degree.-150.degree. C. with subsequent axial stretching of the cooled rod at a ratio of 1:3 to 1:10;
- cooling the rod further to room temperature, subjecting the thus-obtained monofil to elongation by winding the monofil on a support with a uniform tensile force of from 150-300 N and thereafter storing the wound monofil for a period of from 5 to 60 minutes.
Dependencies are inferred from the claim text.