DD293379A5 - METHOD FOR PRODUCING OVERALL OR FULLY ORIENTED PROFILED POLYAMIDE FAEDES - Google Patents

Abstract

The invention relates to a process for the preparation of profiled polyamide threads oriented largely or completely. The produced by the process Faeden are suitable for the production of warp knitwear for the outerwear sector and highly fashionable areas in weaving and textile sector. The aim and task is to produce profiled Polyamidfaeden in a material-economical manner with dull gloss and good bulk. According to the invention, this is achieved by spinning a polyamide melt of PA granules having a relative solution viscosity of rel2.40-2.70, a degree of stabilization of * acetic acid per mole of lactam, a residual moisture content of 0.04, by tri- or polylobal profile duplexes 0.03-0.15% by weight of TiO 2 of the anatase modification, after which the freshly spun yarns are blown in until the slenderness level of f 0.12-0.5 is reached and subsequently subjected to stretching texturing. FIG {procedures; Polyamide threads, profiled; Shine, dulled; titanium dioxide; Slenderness ratio; Bauschfaehigkeit; sPINNING; Flaechengebilde}

Description

Field of application of the invention

The process is used in the chemical fiber industry for the production of modified polyamide 6 profile threads. The threads produced by the process are suitable for the production of warp knitwear for the Oberbekeidungssektor and for the design of special high-fashioned flat structures in weaving and textile sector.

Characteristic of the known state of the art

Melt-spun threads made of polyamide 6 or PE have, in addition to many outstanding textile properties, also disadvantages which restrict their possible use in the textile industry. In the case of fabrics made of thread with a round or triangular cross section, for example, the transparency and the greasy luster are particularly troublesome.

The man-made fiber manufacturers strive to reduce or eliminate undesired gloss by deliberately introducing inorganic white pigments, preferably titanium dioxide (TiO ₂ ). Thus, by Ludewig "polyester fibers - chemistry and technology", Akademie-Verlag Berlin, 1975, p 121 out that a sufficient matte effect is achieved by adding 0.3 to 0.6% TiO ₂ .

In the spinning of polyamide fibers or filaments, the matting agent TiO ₂ , as Klare in "synthetic fibers of polyamides", Akademie-Verlag Berlin, 1963, p. 78 and 83 sets out the monomeric starting material ε-caprolactam added and then the polycondensation example performed in the UK pipe.

In the fineness range of polyamide yarns of 4.4 tex, which are processed in Schärwirksektor, while a TiO ₂ -gohalt of 0.30-0.35% has been found to be sufficient in the threads a low gloss and a whiteness of 60 -80%.

It is further known that the physical mechanism of the matting is based on the fact that the introduction and fine distribution of TiO ₂ in the high polymer produces numerous phase boundaries at which the incident light is scattered

It is also known to use other inorganic substances such as zinc sulfide, barium sulfate or calcium sulfate singly or in combination thereof as matting agents. However, these substances all have a lower refractive index than TiO ₂ , so that the difference in the refractive index between the polymer and the material used becomes smaller and thus the matting effect is lower. (JP-PS 58041718; JP-PS 58025363; DD-PS 273843) As is known, TiO _{2 has} a good matting effect, the addition of which adversely affects the costs of the polymerization and spinning processes.

When using other inorganic substances, such. For example, zinc sulfide or barium sulfate are required to achieve a sufficient matte effect higher concentrations than TiO ₂ . Higher concentrations of inorganic foreign substances with a matting effect, however, lead to a decrease in the feinhoitsbezogene thread strength of the silk and reinforced Einschleifeffekt on the Fadenleitorganen and thus there is an increase in filament breakage in the silk, which leads to processing difficulties.

Object of the invention

The aim of the invention is to produce in a simple and economically viable way polyamide 6 threads with dull gloss, which can be processed free of troublesome thread breaks or lint to high-quality textlien fabrics.

Explanation of the essence of the invention

The object of the invention is to produce modified Profilpolyamidfäden with reduced gloss and good noise ability of high quality while reducing the usual addition ar TiO ₂ content.

According to the invention largely or completely oriented profiled polyamide yarns are made with dull gloss and good bulkability, if a polyamide melt of PA6 granules having a relative solution viscosity of ζ ,, ι = 2.40-2.70, a degree of stabilization of 0.1-0 , 2% acetic acid per mole lactam, a residual moisture content of = s0.04Ma .-%

spun by tri- or polylobal profile nozzles, which 0.03-0.15 parts by weight in ⁰ ATiO _{2 of} the modification anatase, whereupon the freshly spun threads until the achievement of the degree of slimming φ = 0.12-0.5 blown, prepared and wound up and subsequently subjected to stretching texturization.

Ausführungsbaispiel

The invention will be explained in more detail using an exemplary embodiment.

Fig. 1: thread profile trilobal Fig.2: thread profile tetralobal

example 1

In a known polycondensation is polyamide 6 granules with a degree of stabilization of 0.145% acetic acid per mole of lactam, a relative Lösungsviskositat of ζ ,, ι = 2.66 to 2.68. a residual moisture content of 0.028 parts by weight in% and a TiOj content of 0.09 parts by weight in%. The granulate is melted at 265-270 ⁰ C and yarns with a linear density of 4.4 tex f 10 after the rapid spinning process at a rate of 3920m · min ^"1 through 10 hole spinnerets with a trilobal or tetralobal profile according to Fig. 1 or Fig 2, wherein the freshly spun threads in the injection shaft are blown with air in such a way that the slenderness degree φ measured at the cross section of the thread lies between 0.125-0.14 The slenderness degree φ is defined as

,, .. ,,. h Γ mm 1

Relationship -

H [mm J

h = depth of the recess H = profile diameter

and characterizes the depth of the cloverleaf indentations of the trilobal cross-sectional shape.

After a climate storage of the coils of 3 days at 18 ⁰ C and 65-67% relative humidity, the profiled SSW silk was stretch-texturized by the false twist method at a re-stretch ratio 1: 1.23 and a fixing temperature of 180 ° C.

The textile-physical examination on this textured SSW-profile silk with a linear density of 4.4 tex 10 resulted in a fineness-related strength of 300-315 m N / tex, an elongation at break of 33-35% and a gloss number of G = 3-5, which was high normal polyamide-6 silk with a round cross-section and a TiO ₂ content of 0.35%.

The profiled silk with low gloss produced by the process has a soft bulky feel and a good running behavior during further processing.

Comparative example

If, however, in a polycondensation a polyamide-6-Glanzgranulat with a degree of stabilization of 0.10 to 0.12% acetic acid and having a relative solution viscosity of ζ ,, ι = 2.56-2.60 prepared at 373K under vacuum to a Residual water content of 0.032% wt. Dried down and melted in the extruder of a high-speed spinning machine, the freshly spun triangular filaments are wound continuously according to Figure 1 with a take-off speed of 3840 m / min with a thread count of 4.4 tex f 10. The thus prepared Saide has a φ-value of 0.07-0.09 with a fineness-related strength of 320-34Om N / tex, an elongation at break of 70-72% and a greasy gloss with a gloss number of G = 16-18, measured according to Klinghardt (TGL 1422008) and is therefore not suitable for fashionable matt fabrics.

Claims (1)

Process for the preparation of substantially or completely oriented profiled polyamide threads with matte effect and good bulkability by spinning a polymer melt of polyamide granules (PA6) with a relative solution viscosity of ζ _Γβ ι = 2.40-2.70, a degree of stabilization of 0.1-0, 2% acetic acid per lactam, a residual moisture content of "S0.04% by tri-poly-polygonal profiled nozzles, whereupon the resulting filaments are cooled, prepared and wound, characterized in that the polyamide melt 0.03-0.15 parts by weight of TiO ₂ in% of the modification Anatase, the threads are blown until reaching the slenderness degree φ = 0.12-0.5 and then subjected to a stretch texturing. For this 1 page drawings