EP0804640B1

Improvements in continuous filaments, yarns, and tows

Abstract

This record has no abstract on file.

EP0804640B1, drawing sheet 1
Sheet 1 of 54

Term

Term ended

Expired 21 November 2014, 11.8 years ago.

  1. Priority
  2. Filed
  3. Granted
  4. Expired
  5. Today

25 claims: 18 independent, 7 dependent

  1. 1
    A process for preparing spin-oriented polyester filaments, involving first melt-spinning a polyester polymer having a glass transition temperature (T g ) of 40 to 80°C and a zero-shear polymer melting point (T M °) of 240 to 280°C at a withdrawal speed in the range of 2 to 6 Km/min, and quenching to a temperature below said temperature (T g ), to form polyester filaments (A) of low shrinkage (S) as defined hereinafter in paragraph (iv), characterized by treating said filaments (A) by rapidly heating to a treatment temperature above said temperature (T g ) and up to [O.775(T M ° + 273)-273], and then immediately and rapidly cooling the filaments to below said temperature (T g ), wherein said heating and cooling are carried out at rates sufficiently rapid to provide filaments having:i) a residual draw-ratio (RDR) of 1.4 to 1.9, a post yield modulus (M py ) of less than 12 g/dd (11 dN/ drawn tex), and shrinkage (S) such that the value of (1-S/S m ) is between 0.25 and 0.95;where RDR is (1+100/E B ,%), E B being the elongation-to-break, and S m is [(6.5-RDR)/6.5]x100%;ii) a high maximum shrinkage tension (ST max ) of 0.1 g/d to 0.5 g/d (0.1 to 0.4 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M ° + 273)-273] and [0.725(T M ° + 273)-273];and iii) a shrinkage modulus (M s ) of up to 5 g/d (4 dN/tex) ;and high shrinkage power (P s ) of 1.5 to 12 (g/d)% (1.3 to 11 dN/tex%);and wherein said filaments (A) have: iv) a residual draw-ratio (RDR) between 1.4 and 1.9 and low shrinkage (S) such that the value of (1-S/S m ) is at least 0.9;and v) a maximum shrinkage tension (ST max ) less than 0.15 g/d (0.13 dN/tex) at a peak shrinkage tension temperature T(ST max ) less than [0.70(T M ° + 273)-273].
  2. 2
    A process according to Claim 1, characterized in that said heating and cooling are carried out at rates sufficiently rapid to provide filaments (B) having shrinkage (S) sufficiently high such that the value of (1-S/S m ) is between 0.25 and 0.9.
  3. 4
    A process according to any of Claims 1 to 3, characterized in that said filaments (A) are melt spun at said withdrawal speed and are immediately treated in a coupled process by said rapidly heating and cooling to provide filaments that are wound up at a speed between about 2 and 6 km/min.
  4. 5
    A process according to any of the preceding claims, characterized by melt-spinning said filaments (A) from a spinneret capillary orifice comprised of multiple segments arranged in a configuration such as to form multiple melt streams which are withdrawn from the spinneret into a quench zone under conditions which cause self-coalescence of the multiple melt streams into a filament having an off-center longitudinal void of at least 10% by volume.
  5. 6
    A process according to any of the preceding claims, characterized by passing said filaments (A) over a surface of sufficient friction to provide irregular, asymmetric filaments before they are rapidly heated.
  6. 7
    A process according to any of the preceding claims, characterized in that filaments (A), having an asymmetric cross-section with one side larger than the other, are spun through a capillary of configuration selected to provide such asymmetric cross-section.
  7. 8
    A process according to any of the preceding claims, characterized by drawing the resulting filaments at a temperature T D between [0.65(TM°+273)-273] and [0.725(TM°+273)-273] to a drawn residual draw ratio (RDR) D between 1.2 and 1.4 under conditions selected to maintain T(ST max ) in the range {0.65(TM°+273)-273} and {0.725(TM°+273)-273}, shrinkage modulus (M s ) less than 5 g/d (4 dN/tex), and (1-S/S m ) greater than 0.7;and to provide a maximum shrinkage tension (ST max ) of 0.3 to 0.7 g/d (0.3 to 0.6 dN/tex), shrinkage power (P s ) of 5 to 12 (g/d)% (4 to 11 dN/tex%) and post-yield modulus (M py ) less than 12 g/dd (11 dN/drawn tex).
  8. 9
    A process according to any of the preceding claims, characterized by draw-texturing the resulting filaments at a draw ratio selected so as to provide a textured yarn of residual elongation E B 15% to 45%.
  9. 10
    A process according to any of Claims 2 or 4 to 9, characterized by spinning a bundle of filaments (A) and splitting said bundle into two smaller filament bundles, treating one of said smaller filament bundles by said rapidly heating and cooling to provide said filaments (B), and later recombining into a single bundle so as to provide a mixed-shrinkage polyester filament yarn comprising filaments (A) and filaments (B).
  10. 11
    A process according to any of Claims 2 or 4 to 9, characterized in that, before said filaments (A) are rapidly heated, they are mixed with filaments selected from the group consisting of thermally stable polyester filaments (A') and polyamide filaments (C') to form a mixed-filament yarn that is treated by being rapidly heated and cooled to provide a mixed-shrinkage filament yarn comprising said filaments (B) and filaments selected from the group consisting of thermally stable polyester filaments (A') and polyamide filaments (C').
  11. 12
    A process according to any of Claims 2 or 4 to 9, characterized by splitting a melt stream of said polyester polymer into at least two, modifying the polymer in one of the resulting split streams to change its ability to undergo stress-induced crystallization, spinning both the resulting modified polymer and the polyester polymer that has not been so modified to form filaments (A') from the modified polymer and of filaments (A) from such unmodified polymer at a withdrawal speed in the range of 2 to 6 Km/min, and quenching to a temperature below said temperature (Tg), to form a bundle of said polyester filaments (A) of low shrinkage (S) and of thermally stable polyester filaments (A') of low shrinkage (S) from the said modified polymer, heating said bundle to a treatment temperature above said temperature (Tg) and up to [0.775(TM°+273)-273], and then immediately and rapidly cooling to below said temperature (Tg), to provide a mixed-shrinkage polyester filament yarn comprising filaments (A') and filaments (B), wherein said heating and cooling are carried out at rates sufficiently rapid to convert said filaments (A) into filaments (B) as defined in Claim 2 and wherein said filaments (A') have:i) a residual draw-ratio (RDR) of 1.4 to 1.9, a post yield modulus (M py ) of less than 12 g/dd (11 dN/drawn tex), and high shrinkage (S) such that the value of (1-S/S m ) is between 0.25 and 0.9;where RDR is (1+100/E B ,%), E B being the elongation-to-break, and S m is [(6.5-RDR)/6.5]x100%;ii) a high maximum shrinkage tension (ST max ) of 0.1 g/d to 0.5 g/d (0.1 to 0.4 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M ° + 273)-273] and [0.725(T M ° + 273)-273];and iii) a shrinkage modulus (M s ) of up to 5 g/d (4 dN/tex);and high shrinkage power (P s ) 1.5 to 12 (g/d)% (1.3 to 11 dN/tex %).
  12. 13
    A process according to any of Claims 10 to 12, characterized by heat-relaxing said mixed-shrinkage filament yarn to provide a mixed-filament bulky yarn.
  13. 14
    A process according to Claim 13, characterized by air-jet texturing said mixed-shrinkage filament yarn and heat-relaxing during or after air-jet texturing to provide a textured yarn.
  14. 15
    A process according to any of Claims 10 to 14, characterized by drawing the mixed-shrinkage filament yarn at a temperature T D between [0.65(T M °+273)-273] and [0.725(T M °+273)-273] to a drawn residual draw ratio (RDR) D between 1.2 and 1.4 under conditions selected to maintain T(ST max ) in the range {0.65(T M °+273)-273} to {0.725(T M °+273)-273]}, shrinkage modulus (M s ) less than 5 g/d (4 dN/tex), and (1-S/S m ) greater than 0.7;and to provide a maximum shrinkage tension (ST max ) of 0.3 to 0.7 g/d (0.3 to 0.6 dN/tex), shrinkage power (P s ) of 5 to 12 (g/d)% (4 to 11 dN/tex%) and post-yield modulus (M PY ) less than 12 g/dd (11 dN/drawn tex).
  15. 16
    A process according to any of Claims 10 to 15, characterized by draw-texturing said mixed-shrinkage filament yarn at a draw ratio selected so as to provide a textured yarn of residual elongation E B of 15% to 45%.
  16. 17
    A process for preparing spin-oriented polyester bicomponent filaments (A'B) from a polyester polymer having a glass transition temperature (T g ) of 40 to 80°C and a zero-shear polymer melting point (T M °) of 240 to 280°C, characterized by splitting a melt stream of said polyester polymer into at least two, modifying the polymer in one of the resulting split streams to change its ability to undergo stress-induced crystallization, recombining the split stream in an adjoining relationship into a single melt stream, spinning the single melt stream into filaments at a withdrawal speed in the range of 2 to 6 Km/min, and quenching to a temperature below said temperature (T g ), to form intermediate polyester bicomponent filaments (A'A), followed by rapidly heating said intermediate bicomponent filaments (A'A) to a treatment temperature above said temperature (T g ) and up to [0.775((T M ° + 273)-273], and then immediately and rapidly cooling the filaments to below said temperature (T g ), wherein said heating and cooling are carried out at rates sufficiently rapid to provide bicomponent filaments (A'B) characterized by:i) a residual draw-ratio (RDR) of 1.4 to 1.9, and high shrinkage (S) such that the value of (1-S/S m ) is greater than 0.7, where RDR is (1+100/E B ,%), E B being the elongation-to-break, and S m is [(6.5-RDR/6.5]X100%;and ii) a high maximum shrinkage tension (ST max ) of 0.1 to 0.5 g/d (0.1 to 0.4 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M ° + 273)-273] and [0.725(T M ° + 273)-273];and iii) a shrinkage modulus (M s ) of up to 5 g/d (4 dN/tex);and high shrinkage power (P s ) of 1.5 to 12 (g/d)% (1.3 to 11 dN/tex%);and wherein said intermediate bicomponent filaments (A'A) have: iv) a residual draw-ratio (RDR) between 1.4 and 1.9 and low shrinkage (S) such that the value of (1-S/S m ) is at least 0.9;and v) a maximum shrinkage tension (ST max ) less than 0.15 g/d (0.13 dN/tex) at a peak shrinkage tension temperature T(ST max ) less than [0.70(T M ° + 273)-273].
  17. 18
    A process for preparing spin-oriented polyester/polyamide bicomponent filaments (BC'), characterized by first melt-spinning intermediate bicomponent filaments (AC') from a polyester polymer having a glass transition temperature (T g ) of 40 to 80°C and a zero-shear polymer melting point (T M °) of 240 to 280°C, and from a polyamide polymer, in an adjoining relationship, at a withdrawal speed in the range of 2 to 6 Km/min, and quenching said intermediate bicomponent filaments (AC') to a temperature below said temperature (T g ), followed by treating said intermediate bicomponent (AC') by rapidly heating to a treatment temperature above said temperature (T g ) and up to [0.775(T M ° + 273)-273], and then immediately and rapidly cooling the filaments to below said temperature (T g ), wherein said heating and cooling are carried out at rates sufficiently rapid to provide filaments (BC') having:i) a residual draw-ratio (RDR) or 1.4 to 1.9, a post yield modulus (M py ) of less than 12 g/dd (11 dN/drawn tex), and high shrinkage (S) such that the value of (1-S/S m ) is greater than 0.7, where RDR is (1+100/E B ,%), E B being the elongation-to-break, and S m is [(6.5-RDR)/6.5]X100%;ii) a high maximum shrinkage tension (ST max ) of 0.1 to 0.5 g/d (0.1 to 0.4 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M ° + 273)-273] and [0.75T M ° + 273)-273];and iii) a shrinkage modulus (M s ) of up to 5 g/d (4 dN/tex) ;and high shrinkage power (P s ) of 1.5 to 12 (g/d)% (1.3 to 11 dN/tex%);and wherein said intermediate bicomponent filaments (AC') have: iv) a residual draw-ratio (RDR) between 1.4 and 1.9 and low shrinkage (S) such that the value of (1-S/S m ) is at least 0.9;and v) a maximum shrinkage tension (ST max ) less than 0.15 g/d (0.13 dN/tex) at a peak shrinkage tension temperature T(ST max ) less than [0.70 (T M ° + 273)-273)].
  18. 19
    A process according to Claim 18, characterized by spinning said polymers into a symmetric sheath/core bicomponent filament relationship, with a sheath of nylon 66 polyamide and a core of poly(ethylene terephthalate) polyester, from melt at a polymer temperature (Tp) that is 20 to 50°C above the melting point (T M °), and wherein the polyester and polyamide polymers are selected to have similar melt flow viscosities of the same order of magnitude at the polymer temperature (Tp).
  19. 20
    A process according to Claim 18 or 19 for preparing symmetric sheath/core, respectively polyamide/polyester, bicomponent spin-oriented filaments characterized by melt-spinning such filaments from a polyamide polymer and from a polyester polymer in a symmetric sheath/core adjoining relationship, and wherein the compositions of said polymers and the spinning and quenching conditions are so selected to provide both sheath and core elements having boil-off shrinkages that are approximately the same and between 3 and 30%, and to provide filaments (BC') having an initial modulus (M i ) greater than 20 g/d (18 dN/tex), and shrinkage (S) such that the value of (1-S/S m ) is greater than 0.7.
  20. 21
    A process according to any of Claims 17 to 20, characterized by drawing the resulting bicomponent filaments at a temperature T D between [0.65(T M °+273)-273] and [0.725(T M °+273)-273] to a drawn residual draw ratio (RDR) D between 1.2 and 1.4 under conditions selected to maintain T(ST max ) in the range {0.65(T M °+273)-273} to [0.725(T M °+273)-273], shrinkage modulus (M s ) less than 5 g/d (4 dN/tex), and (1-S/S m ) greater than 0.7;and to provide a maximum shrinkage tension (ST max ) of 0.3 to 0.7 g/d (0.3 to 0.6 dN/tex), shrinkage power (P s ) of 5 to 12 (g/d) % (4 to 11 dN/tex%) and post-yield modulus (M PY ) less than 12 g/dd (11 dN/drawn tex).
  21. 22
    Spin-oriented polyester filaments having:i) a shrinkage (S), such that the value of (1-S/S m ) is between 0.25 and 0.9, where S m is [(6.5-RDR/6.5]X100%, an elongation-to-break between 40% and 90%, a post yield modulus (M py ) of less than 12 g/dd (11 dN/drawn tex), and a residual draw ratio (RDR) between 1.4 and 1.9, where RDR is (1+E B /100);ii) a maximum shrinkage tension (ST max ) between 0.1 g/d and 0.7 g/d (0.1 to 0.6 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M ° +273)-273] and [0.725(T M °+273)-273], where T M ° is the zero-shear polymer melting point and is between 240°C and 280°C;iii) a shrinkage power P s of 1.5 to 12 (g/d)% (1.3 to 11 dN/tex%) and a shrinkage modulus M s up to 5 g/d (4 dN/tex).
  22. 23
    A mixed-shrinkage filament yarn, characterized by comprising high shrinkage filaments according to Claim 22, and low shrinkage filaments that are selected from the group consisting of polyester filaments and polyamide filaments, and having:i) a low boil off shrinkage (S), such that the value of (1-S/S m ) is at least 0.9, where S m is [(6.5-RDR)/6.5]x100%, and where RDR is (1+100/E B ,%) and E B is the elongation-to-break;ii) a maximum shrinkage tension (ST max ) less than 0.15 g/d (0.13 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T m °)+273) -273] and [0.70(T m °)+273)-273]. iii) a shrinkage power P s of less than 1.5 (g/d)% (1.3 dN/tex %) and a shrinkage modulus M s up to 5 g/d (4 dN/tex).
  23. 24
    Spin-oriented polyester bicomponent filaments having 2 polyester components, characterized by:i) a residual draw-ratio (RDR) of 1.4 to 1.9, and shrinkage (S) such that the value of (1-S/S m ) is greater than 0.7, where RDR is (1+100/E B ,%), E B being the elongation-to-break, and S m is [(6.5-RDR)/6.5]x100%;ii) a high maximum shrinkage tension (ST max ) of 0.1 g/d to 0.5 g/d (0.1 to 0.4 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M °)+273)-273] and [0.725(T M °)+273)-273], wherein T M ° is the weighted average value of the zero-shear melting point of the polyester polymers comprising the bicomponent filaments, iii) a shrinkage modulus (M s ) up to 5 g/d (4 dN/tex) ;and a shrinkage power (P s ) of at least 1.5 (g/d)% (1.3 dN/tex%).
  24. 25
    Spin-oriented bicomponent filaments having a polyester component and a polyamide component characterized by:i) a residual draw-ratio (RDR) of 1.4 to 1.9;and shrinkage (S) such that the value of (1-S/S m ) is greater than 0.7, where RDR is (1+100/E B ,%), E B being the elongation-to-break, and S m is [(6.5-RDR)/6.5]x100%;ii) a high maximum shrinkage tension (ST max ) of 0.1 g/d to 0.5 g/d (0.1 to 0.4 dN/tex) at a peak shrinkage tension temperature T(ST max ) between [0.65(T M °+273)-273] and {0.75(T M °+273)-273], where T M ° is the polymer zero-shear melting point of the polyester component. iii) a shrinkage modulus (M s ) up to 5 g/d (4 dN/tex);and a shrinkage power (P s ) of at least 1.5 (g/d)% (1.3 dN/tex%).
Independent claims24