Classifications

• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/02—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of forming fleeces or layers, e.g. reorientation of yarns or filaments
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/08—Melt spinning methods
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D4/00—Spinnerette packs; Cleaning thereof
  • D01D4/02—Spinnerettes
  • D01D4/025—Melt-blowing or solution-blowing dies
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/08—Melt spinning methods
  • D01D5/084—Heating filaments, threads or the like, leaving the spinnerettes
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/08—Melt spinning methods
  • D01D5/088—Cooling filaments, threads or the like, leaving the spinnerettes
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/08—Melt spinning methods
  • D01D5/098—Melt spinning methods with simultaneous stretching
  • D01D5/0985—Melt spinning methods with simultaneous stretching by means of a flowing gas (e.g. melt-blowing)
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/08—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating
  • D04H3/16—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating with bonds between thermoplastic filaments produced in association with filament formation, e.g. immediately following extrusion

Definitions

• the invention relates to a method for producing microfilaments according to the preamble of claim 1, and moreover the invention also relates to a spinning device for producing microfilaments.
• Synthetic filaments with a single titer of less than 1 dtex are designated as microfilaments (the specification 1 dtex means that 10 km of the thread or filament weighs 1 gram).
• the microfilaments therefore have a very small diameter and are twisted in a known manner to form microfilament yarns.
• These microfilament yarns can be woven or knitted to make a textile. Due to the single titer of less than 1 dtex, the textiles are characterized by 'a very soft feel and an ⁇ dall case, so that they have a silk-like character and can follow the fashion trend of silk fabrics.
• microfilaments takes place in that the microfilament is drawn off and stretched at a high take-off speed from the spinning hole of a spinneret fed with a melt and is taken up on a roll after passing through an area blown transversely with cooling air. This is followed by twisting with a large number of microfilaments into a microfilament yarn from which the desired textile can be produced by weaving.
• spunbonded nonwovens from the microfilaments by pulling the filaments emerging from spinning nozzles under the action of an injector after passing through an area blown transversely with cooling air and depositing them on a continuously moving deposit belt.
• Such spunbonded fabrics made from microfilaments are also covered by the invention.
• the fila diameter depending on the synthetic polymer used, is below 12 ⁇ m for polypropylene and below 11 ⁇ m for polyamide or below 10 ⁇ m for polyester.
• the microfiber yarns and textile products resemble the fashionably preferred natural silk due to their soft feel.
• the textile yarns made from microfilaments have yet another advantage that can be attributed to the tightness of the fabric. Fabrics made from microfilament yarns can be woven so densely that their diffusion properties are similar to those of impervious diaphragms. These flat structures breathe, ie they let gases and also vapors, such as water vapor, through easily, even though they are poorly wettable at the same time. The. poor wettability is due to the small filament diameter and the resulting unfavorable angles between two filament surfaces.
• the polymer melt is extruded through the spinneret, cooled by an air stream below the spinneret and drawn off at high speed - usually around 6,000 m / min.
• the aim in practice is to reduce the diameter of the microfilaments to a single titer of well below 1 dtex to reduce.
• the number 'of the microfilaments in the yarn or the number of nozzle holes per must Mikrofila- dewaxing proportional to the reduction of the single titer i. d-tex rise because several microfilaments are then required to produce a microfilament yarn with the same diameter.
• the filament surface is inversely proportional to the third power of the filament diameter for the same volume. If, for example, the individual titer is halved, the thinner filament has an eightfold surface.
• the larger surface area can be seen in connection with the cooling of the microfilament.
• the stretching of the microfilament presupposes a certain temperature, and if it cools down too much, there is a risk that the microfilament will become brittle and tear off, especially at the usual high take-off speeds of 6,000 m / min.
• hypothermic skin will form on the surface of the microfilament. This skin is responsible for the filament breaks.
• the skin is already rigid, while the inner mass, which is surrounded by the skin, is still in a stretchable state.
• the invention is based on the object of specifying a method which enables the production of microfilaments with very small diameters without deterioration in economy and quality, and moreover the invention is intended to create a spinning device which enables economical production of microfilaments allowed with small diameters.
• this object is achieved in the method presupposed in the preamble of patent claim 1 by the features of the characterizing part, and with regard to the spinning device, the task in a spinning device according to the preamble of patent claim 10 is achieved by the method characteristic features solved.
• the invention provides that the microfilaments are accompanied by a downward flow of hot air immediately after they exit the spinning hole.
• the extruded filament is thus embedded in a warm air stream after exiting the spinning hole, which preferably surrounds the filament in the form of a jacket.
• the hot air coating compensates for the negative influence of the large surface area of the microfilaments, which leads to rapid cooling. This prevents the filament from cooling too quickly, owing to the much higher specific surface area.
• a major advantage of the invention is therefore that the filament can be drawn off without problems even at the usual high speeds of 4,000-6,000 n / min. "
• microfilament yarns produced by the process according to the invention thus provide a significantly better quality, the disadvantages described at the outset being eliminated.
• the protective jacket made of hot air protects the just extruded and formed filament immediately after it emerges from the spinning hole of the spinneret from cooling too quickly. Thus, a rapidly cooled outer skin of the filament cannot arise, which would be damaged by the shear stress caused by the rapid filament withdrawal without cracks and would lead to a filament breakage.
• the filament cools gradually, so that - viewed radially - a uniform structure is formed.
• the very fine microfilament with a small diameter can also be optimally stretched.
• differences between the individual filaments of a multifilament spinneret are largely suppressed, - Io ⁇
• the cooling of the microfilament is under control, so that the risk of microfilaments with different diameters being avoided is avoided.
• deviations in the diameters in the prior art are only slight, they are nevertheless noticeable, e.g. in that when the microfilaments or the textile are colored, the color of the different microfilaments with different diameters is also taken up differently. As a result, the uniform color impression of the product used as a high-quality textile suffers.
• the method for producing microfilaments also includes known very small diameter
• polyolefins especially polypropylene, furthermore polyester and polyamide 6 and 6,6 can be spun by the process according to the invention.
• Known bicomponent nozzles can advantageously be used, whereby it must be ensured that the outer part of the combined spinneret is modified in such a way that a uniform distribution of the hot air over all bores is ensured. Furthermore, the outer holes of the combined nozzle must be adapted to the air flow.
• Such bicomponent nozzles have a jacket-core arrangement / in which case only the core nozzle is used for spinning the polymer melt and the hot air flow is generated at the jacket nozzle.
• the spinning conditions with regard to the polymer melt can essentially be maintained as they are set when spinning a conventional spinning device.
• the air temperatures in the outer part of the spinneret (bicomponent nozzle) depend on the melting temperature.
• moderate embodiment of the invention provides that the temperature difference between the two components should not be exceeded ⁇ 10 ° C. In the optimal case, the temperatures of the two components, melt and air, are equal.
• the amount of air in the hot air can be adjusted in a simple manner, a minimum setting being necessary in order to ensure that a clean free jet forms at least briefly below the spinneret.
• the microfilaments After running a distance of approximately 100 to 500 mm below the spinneret, the microfilaments can be cooled to a greater extent by transverse blowing, and the usual blowing shafts can be used here.
• aerodynamic take-off devices in the form of an injector can also be used expediently within the scope of the invention, so that the microfilaments formed according to the invention are known in a known manner Way also a spinning fleece can be formed.
• FIG. 1 shows a schematic representation of a known spinning device with a mechanical take-off device in the form of a roll
• Fig. 2 shows a spinning device
• FIG. 4 shows a detailed illustration of a bicomponent nozzle used in FIG. 3.
• the spinning device designated as a whole with the reference number 10 in FIG. 1 is known per se. It has a spinneret 1-2 with a spinning hole 14, through which melt 16 exits and is stretched into a microfilament 18.
• a rotating roller 20, on which the microfilaments 18 are rolled up, serves as the take-off device.
• the illustration according to FIG. 1 shows only the case of a single microfilament. In practice, if a large number of microfilaments are produced, the spinneret 12 has a corresponding number of spinning holes 14.
• the melt 16 When leaving the spinning hole 14, the melt 16 has a temperature of approximately 280 ° C. A transverse blowing with cooling air is indicated by the arrow 22, and the microfilament 18 cools down to such an extent that it still has a temperature of about 60 ° C. at the bottom of the roll.
• the microfilament 18 is thus stretched by the roll, the rotational speed of which is decisive for the take-off speed.
• a typical value of the take-off speed in FIG. 1 is 4000 to 6000 m / min.
• 1 shows a spinning device for production 2 shows a known spinning device for producing spunbonded nonwovens.
• the take-off device is aerodynamically designed and formed by an injector 24.
• the microfilaments are deposited on a laterally moving catch belt 36.
• a practical embodiment of the method according to the invention results from the embodiment of the spinning device according to FIG. 3.
• the extruded microfilament 18 is embedded in a warm air flow indicated by the arrows A.
• This warm air flow A accompanies the microfilament essentially within the stretching area 38, which is the main stretching area with a length of approximately 30 to 50 cm.
• the total distance 1 between the bicomponent nozzle 26 and the roller 20 is approximately 1 m.
• the microfilament 18 is blown transversely with cooling air 22, as in FIGS. 1 and 2.
• the temperature of which is the melt temperature of 280 ° C at the exit through the spinning hole 14 should not exceed or differ by ⁇ 10 ° C., too rapid cooling of the microfilament 18 is prevented. Rather, the cooling of the microfilament 18 is delayed and carried out continuously in the invention.
• the invention ensures that, despite a reduction in the diameter of the microfilament 18, it is possible to work with the usual take-off speed of 4000-6000 m / min, so that the economy of a spinning system is not lost if smaller diameters of the microfilaments are desired.
• a bicomponent nozzle 26 which is shown in more detail in FIG. 4 and has a core nozzle 28 and a jacket nozzle 30 and also has an annular gap 32, can be used to generate the hot air flow A which is decisive in the invention.
• the annular gap 32 surrounds ring-shaped the spinning hole 34 from which the melt emerges.
• melt is extruded both through the spinning hole 34 of the core nozzle 28 and through the annular gap 32 of the jacket nozzle 30, it is provided according to FIG. 4 that the melt exits exclusively via the inner core nozzle 28 .
• the hot air flow is supplied or generated through the annular gap 36 under pressure p and temperature T, which then surrounds the microfilament 16 in the form of a jacket.
• the invention can also be used for the production of spunbonded fabric in a spinning device according to FIG. 2.
• microfilament yarns with a super fine single titer of 0.33 dtex can be produced without sacrificing the economy of a spinning system, so that it is possible to produce textiles that are practically equivalent to natural silk.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Mechanical Engineering (AREA)
• Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
• Artificial Filaments (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6395741

Family Applications (1)

Country Status (7)

Cited By (1)

Families Citing this family (13)

Citations (5)

Family Cites Families (12)

• 1989
  • 1989-12-19 DE DE3941824A patent/DE3941824A1/de active Granted
• 1990
  • 1990-12-03 AT AT90917481T patent/ATE107971T1/de not_active IP Right Cessation
  • 1990-12-03 KR KR1019920701460A patent/KR920703889A/ko not_active Withdrawn
  • 1990-12-03 EP EP90917481A patent/EP0541552B1/de not_active Expired - Lifetime
  • 1990-12-03 JP JP3500064A patent/JP2918332B2/ja not_active Expired - Fee Related
  • 1990-12-03 US US07/862,570 patent/US5310514A/en not_active Expired - Fee Related
  • 1990-12-03 DE DE59006327T patent/DE59006327D1/de not_active Expired - Fee Related
  • 1990-12-03 WO PCT/DE1990/000941 patent/WO1991009162A1/de active IP Right Grant

Patent Citations (5)

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