Production of synthetic fibers

Claim 2

A process for the spinning of synthetic fibers comprising dissolving at least one polycondensation product of at least one polyfunctional phenol component with the phenolic groups attached to a central carbon atom so they are hindered in their free rotation and at least one polyfunctional carboxylic acid having an inherent viscosity η inh greater than 0.5 dl/g in a solvent with a boiling point less than 100° C. to form a spinning solution, forcing the spinning solution through spinning nozzles into a liquid precipitant for fiber formation at a temperature at least 8° C. less than the solvent boiling point to withdraw the majority of the solvent from the fibers, stretching the resulting fibers to 2 to 6 times their length and removing the residual solvent.

Claim 3

A process for the spinning of synthetic fibers comprising dissolving at least one polycondensation product of at least one polyfunctional phenol component with the phenolic groups attached to a central carbon atom so they are hindered in their free rotation of the formula ##STR3## wherein each R is selected from the group consisting of hydrogen and lower alkyl and X is selected from the group consisting of ##STR4## Y representing the atoms necessary to close a lower cycloaliphatic ring and R' and R" each is a member of the group consisting of hydrogen, an alkyl radical of 1 to 7 carbon atoms, a phenol radical, a cycloalkyl radical of 4 to 8 carbon atoms and a haloalkyl of 1 to 7 carbon atoms radical and at least one polyfunctional carboxylic acid chloride having an inherent viscosity η inh greater than 0.5 dl/g in a solvent with a boiling point less than 100° C. to form a spinning solution, forcing the spinning solution through spinning nozzles into a liquid precipitant for fiber formation at a temperature at least 8° C. less than the solvent boiling point to withdraw the majority of the solvent from the fibers, stretching the resulting fibers to 2 to 6 times their length and removing the residual solvent.

Claim 4

A process for the spinning of synthetic fibers comprising dissolving at least one polycondensation product of at least one polyfunctional phenol component with the phenolic groups attached to a central carbon atom so they are hindered in their free rotation of the formula ##STR3## wherein each R is selected from the group consisting of hydrogen and lower alkyl and X is selected from the group consisting of ##STR4## Y representing the atoms necessary to close a lower cycloaliphatic ring and R' and R" each is a member of the group consisting of hydrogen, an alkyl radical of 1 to 7 carbon atoms, a phenol radical, a cycloalkyl radical of 4 to 8 carbon atoms and a haloalkyl of 1 to 7 carbon atoms radical and at least one polyfunctional carboxylic acid chloride having an inherent viscosity η inh greater than 0.5 dl/g in a solvent with a boiling point less than 100° C. to form a spinning solution, forcing the spinning solution through spinning nozzles into a liquid precipitant for fiber formation at a temperature at least 8° C. less than the solvent boiling point to withdraw the majority of the solvent from the fibers, stretching the resulting fibers to 2 to 6 times their length and removing the residual solvent.

Claim 5

The process of claim 1 wherein the liquid precipitant contains an organic solvent miscible with water.

Claim 6

The process of claim 2 wherein the liquid precipitate is a mixture of water and a water miscible organic solvent.