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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4326—Condensation or reaction polymers
  • D04H1/435—Polyesters
• • 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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4382—Stretched reticular film fibres; Composite fibres; Mixed fibres; Ultrafine fibres; Fibres for artificial leather
  • D04H1/43838—Ultrafine fibres, e.g. microfibres
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F8/00—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
  • D01F8/04—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
  • D01F8/06—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyolefin as constituent
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F8/00—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
  • D01F8/04—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
  • D01F8/14—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyester as constituent
• • 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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4282—Addition polymers
  • D04H1/4291—Olefin series
• • 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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/724—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged forming webs during fibre formation, e.g. flash-spinning
• • 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
• • 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
  • D04H3/005—Synthetic yarns or filaments
  • D04H3/007—Addition polymers
• • 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
  • D04H3/005—Synthetic yarns or filaments
  • D04H3/009—Condensation or reaction polymers
  • D04H3/011—Polyesters

Definitions

• the present invention relates to fine denier filament having a plexifilamentary structure composed of a mixture of polymers which are not miscible each other, to nonwoven fabric comprising said filament and having a fine fibrillated structure and also to their production.
• the present inventors have carried out extensive studies for solving the above-mentioned problems and achieved the present invention.
• the method of manufacturing a filament having a plexifilamentary structure according to the present invention comprises that a mixture of polyolefin and polyester having no miscibility each other is dissolved in a solvent under high temperature and high pressure and the resulting one solution phase is spun out from nozzles under the state that the phases of the polymers and the solvent are separated.
• the filament of the present invention is composed of polyolefin and polyester, has a plexifilamentary structure comprising fibrillated filament of very highly fine denier which has not been available yet and is with high tenacity and modulus. Therefore, it is applicable as materials for textile fabrics, knitted fabrics, nonwoven fabric obtained by a dry method, non-woven fabric obtained by a wet method, etc. and stuffed staple fibres and, in addition, is suitable for various purposes such as clothing materials, thermal insulation materials, artificial leather, absorbing materials used as sanitary materials, protective clothings, curtains, bed sheets, wipers, filters, house wrappings, synthetic paper and the like. Since the filament contains polyester, it is not only coloured by pigments but also suitably dyed in the after-treatment.
• the method of manufacturing the nonwoven fabric having a fine fibrillated structure in accordance with the present invention comprises that the filaments having a plexifilamentary structure in which polyolefin and polyester which are immiscible each other are mixed within a range from 5/95 to 95/5 by weight are prepared, then the filaments are made into webs and the webs are bonded by applying heat and pressure thereto so that entire mixed plexifilaments of the filaments are adhered.
• the viscosity of the ethylenic polymers among the above-given ones is 0.3-30 g/10 min in terms of a melt index value as measured by a method of ASTM-D-1238E.
• the melt index value is less than 3 g/10 min, the viscosity of the mixed solution becomes too high whereby a fine denier fibril flilments are hardly obtained while, when it is more than 30 g/10 min, the tenacity of the filament per se lowers and, at the same time, smoothness and stickiness of the filament increase whereby there is a tendency of giving the filaments with no good hadling.
• the viscosity of the propylenic polymers is 1-40 g/10 min in terms of a melt flow rate value as measured by a method of ASTM-D-1238L.
• the melt flow rate value is less than 1 g/10 min, the viscosity of the mixed solution becomes too high whereby a fine denier fibrillated filament is hardly obtained while, when the melt flow rate value is more than 40 g/10 min, the tenacity of the filament per se lowers and smoothness and stickiness of the filament increase whereby there is a tendency of giving the filaments of no good handling.
• the elogation and the orientation of the filament are carried out by means of an explosive power accompanied by evaporation of the solvent and the tenacity of the filament are often decided by the fact whether said filament is well elongated and oriented.
• the explosive power at that time is a vapourizing power as a result of the speed at the moment.
• the solvent is vapourized at a time within a period of not longer than 0.1 second and, during said process, an increase in the concentration of the polymers is resulted within a short period and, at last, only the mixed polymers are precipitated.
• the mixed polymers which are precipitated as a result of vapourization of the solvent are cooled.
• this cooling step is most important and, in obtaining the filaments with high tenacity, the cooling by means of a flash flow and the elongation and the orientation depending upon the cooling speed should be well carried out.
• the polymers which are not miscible each other are used and, therefore, the fibrillation is well promoted by said flash flow whereby very fine denier fibrillated filaments are resulted.
• the nonwoven fabric of the present invention is in such a state that the filaments having a plexifilamentary structure are bonded each other in the entire area.
• the bonding takes place at the bonded areas of very fine denier fibrillated filaments and, therefore, the nonwoven fabric with very dense structure is resulted and the resulting nonwoven fabric is with excellent strength, ability as a bacteria barrier, waterproof pressure and moisture permeability.
• the nonwoven fabric of the present invention exhibits a strength of not less than 20 kg/5 cm calculated in terms of the weight of 100 g/m2.
• the strength is less than 20 kg/5 cm, it is not possible to use for various areas and the use of the nonwoven fabric will be extremely restricted.
• the filaments with a plexifilamentary structure which are opened as such are accumulated on a conveyer and the resulting filament web is subjected to a bonding by application of heat and pressure by means of a group of rolls.
• the conditions for the bonding are as follows. Thus, the temperature is made not lower than "(melting point of the polymer having the lowest melting point among the polymers comprising the filaments) - (40°C)" and not higher than said melting point while the nip pressure of roll axis direction is made from 0.5 kg/cm to 20 kg/cm.
• the definite conditions are suitably chosen at last.
• the bonding with pressure by means of a group of rolls at room temperature and further bonding with pressure under the above-mentioned condition are more preferred since a strong bonding is resulted at the bonded area between the filament and another.
• both of the ratio of the bonded area to the entire area and the density of the bonded area are within the above-mentioned ranges.
• the filaments having a plexifilamentary structure which consititutes the nonwoven fabric is to be manufactured at first.
• the above-mentioned method of flash spinning is applied.
• the conditions for bonding with heat and pressure using a thermal embossing apparatus are as follows.
• the temperature is not lower than "(melting point) - (40°C)" and is not higher than the melting point of the polymer having the lowest melting point among the polymers constituting the filaments.
• the nip pressure of roll axis direction is chosen from a range of 0.5 to 50 kg/cm.
• the processing may be carried out under the nip pressure condition within the above range with a clearance of 0.02-0.2 mm. The clearance is taken for preventing a filmation due to a complete fusion of the bonding area and that may be suitably conducted depending upon the use.
• an embossing under the above-mentioned conditions after a preliminary bonding with heat and pressure using rolls at room temperature because a disorder in the fibrillated filament web is not generated.
• the bonding with heat and pressure is carried out at the temperature of higher than the melting point of the polymer at the embossing step, the filaments are sometimes melted whereby the web is wound round the roller whereby no sheet is produced.
• the very fine denier filaments with a plexifilamentary structure are fused whereby the effect of the very fine denier fibrillated filament is deteriorated.
• the application of the temperature of lower than "(melting point of the polymer) - (40°C)" at the final stage is not preferred since the bonding among the filaments lowers whereby the strength of the nonwoven fabric lowers.
• the conditions for bonding with heat and pressure when a pin-sonic processing apparatus is used are, for example, that the filaments are partially bonded by means of an oscillation using an ultrasonic wave of about 20 kHz so that the state of the nonwoven fabric is maintained. Degree of the heat bonding can be suitably selected by changing the amplitude of the ultrasonic wave.
• said method of heat bonding by ultrasonic waves is applied, the areas other than the bonding area are rarely affected by heat at the bonding step of the web with high heat bonding ability and, accordingly, the nonwoven fabric as a whole can be held in such a state that the thermal shrinkage properties can be still maintained. Accordingly, when the nonwoven fabric with a high thermal shrinkage property is manufactured, the effect can be more effectively achieved.
• Tensilon (type UTM-4-1-100; manufactured by Toyo Baldwin) was used. A sample of 10 cm length was twisted to an extent of 20 times/5 cm at the gauge length of 5 cm and the strength and the elongation were measured at a tensile speed of 5 cm/minute. The measured strength was divided by the above-mentioned fineness to give a strength of the filament. In those operations, the measurements were conducted twenty times and the average value thereof was given.
• the initial tensile resistance (g/d) was measured in accordance with JIS L-1013 7.10 (Measurement of Initial Tensile Resistance) in the measurements of the above strength and elongation of the filament and was established as the modulus value.
• the time required for the temperature rise from 100°C to 220°C was 25 minutes.
• the solution was stirred for ten minutes to give a homogeneous solution.
• the gauge pressure at that time was 110 kg/cm2.
• the valve was immediately released in such a state that a continuously introducing device of compressed nitrogen gas was applied so that the pressure in the autoclave was kept at 110 kg/cm2 whereby the solution was spun out into air from the nozzles (hole diameter: 0.75 mm; L (length)/D (diameter): 1) equipped with a pressure letdown chamber.
• the pressure in the pressure letdown chamber was 92 kg/cm2.
• the resulting filaments were with very good state of fibrillation. No colouration of the filaments was noted and both strength and modulus were high.
• the filaments were dyed with a disperse dye whereupon it was confirmed that they were clearly dyed. Properties of the filaments were as follows: Tensile Strength: 4.85 g/d Elongation: 64% Modulus: 16.7 g/d Specific surface area: 31 m2/g
• Comparative Example 1 the resulting filaments were with good fibrillated state and both filament strength and modulus were relatively high although, since no polyester was contained at all, the dyeing by a disperse dye was no good.
• Comparative Example 2 the dyeing with a disperse dye was good because it contained no polyethylene at all although the fibrillated state was not so good and, in addition, both filament strength and modulus were low.
• the time required for rising the temperature from 100°C to 220°C was 40 minutes. Stirring was continued for ten minutes when the temperature became 220°C to give a homogeneous solution.
• the gauge pressure at that time was 109 kg/cm2.
• the pressure in the pressure letdown chamber was 92 kg/cm2.
• Example 10 The same apparatus as in Example 10 was used and 400 g of polypropylene (melting point: 162°C; density: 0.910 g/cm3; melt flow rate value: 4 g/10 min), 1,100 g of polyethylene terephthalate (melting point: 256°C; relative viscosity: 1.6) and methylene chloride (a solvent) were filled in the autoclave.
• Each 0.2% by weight (to the mixed polymers) of POE (3 moles) lauryl ether and isooctyl laurate were added to the above mixed polymers as the surface-active agents.
• Nonwoven fabric was manufactured by the same conditions as in Example 11 with an exception that polyethylene terephthalate which was copolymerized with 5 molar % of sulfoisophthalic acid (melting point: 247°C; relative viscosity: 1.3) was used and the dissolving and the spinning temperatures were made 200°C.
• the pressure at the dissolving stage was 119 kg/cm2 and the pressure of the pressure letdown chamber was 100 kg/cm2.
• the resulting nonwoven fabric was with a very good state of fibrillation of the filaments without colouring.
• the filaments were bonded throughout the entire surfaces. Accordingly, the strength of the nonwoven fabric was high and both moisture permeability and waterproof pressure were high as well. It was also confirmed that the nonwoven fabric was able to be clearly dyed with a cationic dye.
• the properties of the nonwoven fabric were as follows.
• the webs were laminated and passed through a clearance embossing apparatus of an oil pressure type to manufacture nonwoven fabric of a weight of 50 g/m2.
• the upper roll of the embossing apparatus was an engraved roll while the lower one was a flat roll and both were heating rolls.
• An embossing process was carried out at the nip pressure of roll axis direction of 20 kg/cm, the temperature of 125°C and the speed of 10 m/min without taking a clearance between the upper and the lower rolls.
• the rate of the bonded area of the engraved roll was 25% and the desity of the bonded area was 60/cm2.
• Example 19 The apparatus of Example 19 was used and polyethylene with high desity (melting point: 132°C; density: 0.96 g/cm3; melt index value: 0.6 g/10 min) and polyethylene terephthalate (melting point: 256°C; relative viscosity: 1.4) with varied ratio and 6,200 g (kept constant) of methylene chloride (a solvent) were filled in the autoclave. Each 0.2% by weight (to the above-mentioned mixed polymers) of isooctyl stearate and isostearyl ester were added as the surface-active agents and the autoclave was closed. Then nitrogen was introduced into the autoclave to make the pressure 40 kg/cm2 and a stirring at a suitable speed was initiated together with a heating.
• the concentrations of the components were as given in Table 3.
• the time required for rising the temperature from 100°C to 200°C was 35 mintues and, when the temperature became 200°C, a stirring was continued for ten minutes to give a homogeneous solution.
• the gauge pressure at that time was about 110 kg/cm2. Then three valves were immediately released keeping the pressure in the autoclave at 110 kg/cm2 by means of a continuous introducing apparatus of compressed nitrogen gas to conduct a spinning and, by the same manner as in Example 19, webs were formed and nonwoven fabric was prepared therefrom.
• the resulting nonwoven fabric was with a very good state of fibrillation of the filaments without colouring. Moreover, the filaments were in such a structure that there were many small bonded areas with pressure and, therefore, the nonwoven fabric kept a practically sufficient strength and exhibited excellent softness and moisture permeability. It was also confirmed that the nonwoven fabric was able to be clearly dyed with a disperse dye.
• the properties of the nonwoven fabric were as follows.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Nonwoven Fabrics (AREA)
• Artificial Filaments (AREA)
• Multicomponent Fibers (AREA)

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• 1994
  • 1994-04-06 WO PCT/JP1994/000581 patent/WO1994024347A1/fr active IP Right Grant
  • 1994-04-06 DE DE69431745T patent/DE69431745T2/de not_active Expired - Lifetime
  • 1994-04-06 JP JP52296894A patent/JP3317703B2/ja not_active Expired - Fee Related
  • 1994-04-06 EP EP94912067A patent/EP0645480B1/fr not_active Expired - Lifetime

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