JPH07103489B2 - Method for combining and co-stretching antistatic filaments and non-stretched nylon filaments - Google Patents

Description

BACKGROUND OF THE INVENTION Windley U.S. Pat. No. 3,971,202 discloses electrically conductive sheath-core filaments, such as those described in Hull U.S. Pat. No. 3,803,453, and non-conductive. It discloses that the filament is co-bulked to form a composite yarn. Conductive yarn is about 890 yards /
Min, ypm (m / min, mpm), melt spun and then drawn at least about 2.0 times in a draw string machine to increase strength. Strength is necessary in the next step, for example in a jet producing hot co-bulky with non-conductive fibers. Separately drawn conductive filaments and non-conductive filaments are then combined on rolls in a high temperature chest where they are annealed to reduce shrinkage and the combined yarns are then cobulked. It

Unfortunately, breakage of conductive filaments often occurs at or near the location where filaments are combined. In addition, conductive filament crossover occurs between the ends of the non-conductive filaments on the roll, thereby reducing the proportion of first quality product obtained. Solving these problems is desirable.

SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a method of making a carpet yarn having reduced charging characteristics, the method comprising melt spinning a plurality of non-conductive nylon filaments into a cooling cylinder to provide a spin-oriented conductive material. Of the two-component filaments by air action into the newly spun threadline in the cooling tube, the combined yarns are consolidated on the pull rolls and the combined yarns are drawn and It consists of bulking and then winding the yarn.

DETAILED DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a method for producing a conductive yarn used in the method of the present invention.

FIG. 2 is a schematic representation of the method of the present invention, in which the spin-oriented conductive bicomponent yarn is drawn or fed in a cooling tube with freshly spun non-drawn non-conductive yarn. Prior to reaching the rolls, the combined and combined yarns are advanced to a draw roll, then co-bulked and unpacked.

The method of the present invention provides carpet yarns having reduced charging properties. The yarn consists of less than 10% by weight, preferably 1-10% by weight of conductive two-component filaments and the balance of non-conductive filaments.

It is desirable that the conductive filament be as thin as possible, that is, have a low denier. Conductive filaments that include a polymeric component with carbon black to impart conductivity generally have a dark appearance and thin darkened filaments are unnoticeable. Also, fine filaments provide an economic advantage as the level of antistatic function does not decrease relative to the reduction in denier. That is, thinner filaments retain most of the antistatic capability of thicker filaments, despite the fact that less conductive material is used.

The conductive filaments used in the present invention are made by high speed spinning of a two component filament as described below. A preferred two-component filament is a sheath / core structure, i.e. one in which the non-conductive component completely surrounds the conductive core, and the present specification describes those processes in detail. However, Bowe US Pat. No. 3,969,559
Also included are filaments surrounding more than 50% but less than 100% non-conductive components (or components) as described in US Pat. However, this is not preferred because of the limited variety of conductive materials that can be used and for other reasons.

The polymer of the sheath component that can be used for the conductive filaments of the present invention is the same as described in the above-mentioned Hull patent. Although not necessary for the present invention, it is advantageous to add titanium dioxide as an anti-glare agent and thus to hide the core. If desired, a large amount of TiO ₂ than disclosed in Hull patent may be added to the sheath polymer. A preferred sheathing polymer is a polyamide such as polyhexamethylene adipamide. The core component materials that can be used are the same as those described in the Hull patent and can be made similarly.
The preferred core polymer is polyolefin, most preferably polyethylene. The core polymer should have 10-50% by weight of conductive carbon black dispersed therein. Preferably, the core comprises no more than 10% by volume of the conductive filament.

Materials useful for making two-component filaments in which the non-conducting component surrounds no more than 50% of the conducting component are taught in the Bow patent mentioned above and are the same as those in the Hull patent. The Bow patent also discloses a method of making this filament.

The spinning of the sheath / core filaments useful in the present invention is carried out as shown in FIG. The filament core and sheath material 1 are extruded from the spinneret assembly 2 into a cooling barrel 3 and are cross-flow cooled by room temperature airflow from the left and right. After cooling to a non-greasy state, the filaments are collected by the guides 4 into yarns and steam conditioner tubes 5, guides 6
Through a finishing bath 7 immersed in a finishing bath 8, through a guide 9 and then around a roll 11 associated with a high speed pulling roll 10 and the Hull patent as package 12 in a similar manner. Being rolled up. However, the difference is that the filament is drawn from the cooling zone at a speed of at least 800 ypm (732 mpm), preferably 1250 to 1500 ypm (1143 to 1372 mpm), as described in Adams patent 3,994,121. That is to make the filament thinner. The spinning speed is the speed at which the yarn leaves the cooling zone and is equal to the peripheral speed of the draw or feed roll. The spinning speed is adjusted to produce filaments having a preferred denier of about 6-11. The filament obtained is characterized by a strength of about 1-3 gpd and an elongation of 200-500%. For a two-component filament in which the non-conductive component only partially surrounds the conductive filament,
An extrusion method similar to the Bow patent can be used and the filament is thinned by pulling it from the cooling zone at a suitable rate.

Test method description All measurements, test methods and terms referred to here,
For example, RV, T, E and D are as defined and described in the Windley, Hull and Adams patents referenced above.

Example 1 Sheath Composition Polyhexamethylene adipamide containing 0.3% rutile TiO ₂ and Mn (H ₂ PO ₂ ) ₂ (9 ppmMn) was incorporated into a polymer.
It is prepared by stirring in an autoclave to ensure that the TiO ₂ is well dispersed. The polymer has a relative viscosity (RV) of 40.

Core composition Polyethylene resin [Alathon 4318 manufactured by Deupon, density -.916, melt index-2
3 AST-D-1238] and a conductive carbon black are mixed with an antioxidant 330 (Antioxidant 330) [ethyl corporation, 1,3,5-trimethyl-2,4,6-tris (3,5-di- Searly butyl-4-hydroxybenzyl) benzene] 0.25 wt% is added and combined in a resin to carbon black weight ratio of 71.55: 28.2. Carbon black is a product of Cabot Cor, Boston, Massachusetts.
Vulcan XC available from poration, Boston, Mass)
72 (Vulcan XC-72). Mix carbon black discharge paryon with Banbury mixer, extrude,
Pass and pelletize. The pellets are re-melted, extruded and passed through a pelletizing agent which holds 31 micron particles and pelletized. Hull,
The specific resistance as described in US Pat. No. 3,803,453 and measured is less than 10 ohm-cm.

Spinning of Conductive Yarn The polymers described above are described in US Pat. Nos. 2,936,482 and 2,989,798.
The spinneret assembly is spun into a concentric sheath core filament (Concentric shea
th core filaments).

The sheath polymer is melted at normal pressure at 285 ° C. and fed to the pack filter at a rate of 32.9 g / min.

The core polymer containing 1% water is melted in a screen melter. The molten polymer is fed through the filter pack at a rate of 1.4 g / min.

The spinning block temperature is 285 ° C. The core polymer feed hopper is purged with dry inert gas.

The RV of the sheath polymer emerging from the spinneret is about 47, and this increased RV results from the additional polymerization of nylon that occurs during melting.

Antistatic filaments are obtained by extruding molten polymeric material from a spinneret having 24 capillaries. The extruded filaments pass through a 45 inch long chamber where the filaments are cross-flow cooled by room temperature air. The filaments then contact the guides, which focus the filaments into a yarn containing three filaments each. To improve the yarn winding, the yarn is made into a 78-inch long steam conditioning tube [Adams
s) US Pat. No. 3,994,121, Example I]. 1.8 psig steam is introduced into the conditioning tube from two 0.04 inch orifices near the top of the tube and one 0.050 inch orifice near the center of the tube.

The yarn is then finished. The yarn is 1250ypm (1143m
pm) feed roll speed, and yarn is 4.4 g
/ Packaged under denier tension.

Oriented by spinning and thus "spin-oriented""spin"
-Oriented ") 3 filament yarn is characterized by having a strength of 1.8 g / denier and an elongation of 300%. The denier was 33. The core percentage was 2% by volume. The sheath percentage was 98. It was in%.

Manufacture of Carpet yarns Manufacture of Carpet yarns will be best understood with reference to FIG. Some ends of the conductive yarns described above were combined with unstretched non-conductive yarn threaded lines in front of a puller roll, then the combined yarns were stretched, annealed and Bulky in this way: FIG. 2 shows the production of two ends of a carpet yarn.
In the figure, non-conductive yarn (80 filaments / end)
295 for polyhexamethylene adipamide (72RV)
At −300 ° C., melt spinning is performed into the cooling cylinder 21, and cooling gas is blown into the cooling cylinder 21 and passes through the hot filament 20 at 370 scfm (10.5 m ³ / m). The filament is pulled through the cooling zone by a puller or feed roll 23 rotating at 860 ypm (786 mpm) from the spinneret 22. The conductive yarn 24, which was supplied from the package, was passed through a forging jet 25, which was supplied with 30 psig (206.9 kPA gauge) of air, by a gas flow to about 2 feet (0.6096) of the spinneret.
m) Directed into the underlying non-conductive thread line and become part of the thread line as they move to the feed roll. After the conductive yarn reaches the supply roll 23, the air to the advancing jet is stopped. After cooling, the integral thread lines 20 'are each focused and treated with a finish by contacting a finish roller 26 partially immersed in a finish trough (not shown).
Adjustment of the "U" guide 27 maintains proper contact with the finishing roller. The threaded line is then rotated around the supply roll 23 and its associated separator roll 28 and around the draw pin assemblies 29, 30 to produce a hot chest.
Proceed to a draw roll 31 (internally heated to produce a surface temperature of 208 ° C.) rotating at 2580 ypm (2359 mpm) enclosed within (not shown). The thread line is a yarn guide 32 and a jet bulky feeding device (jet bulk
ing devices) 34 through the yarn passage 33 at a constant speed by the roll 31. In the jet 34, the thread line 20 'is subject to the bulking action of the hot core (220 ° C) directed through the inlet 35 (only one shown). Hot fluid is discharged along with the thread line to the rotating drum. The rotating drum has a perforated surface on which the yarn cools to set the crimp. From the drum the bulky form of the thread line goes to a guide 37 and then to a pair of take-up rolls 39 which are driven in a path via a pair of guides 38. This type of bulky yarn is known as Breen and Lauterbach.
U.S. Pat. No. 3,186,155. The threaded line 20 'then passes through the fixed guide 40 and through the traverse guide 41 to the rotating core 42 to form the cage 43. Each end of the carpet yarn is 1220 denier [1332 dtex] and contains 83 filaments.

Two other methods are described below as controls A and B.
In A, conductive filaments are described in US Pat. No. 3,972,
Combined with a non-conductive filament on a hot roll as shown in No. 202. At B, the conductive filaments are combined with the non-conductive filaments at the draw pins. The level of filament breakage of the package of the combined yarn of the method of the present invention is 7% of that of method A.
And only 10% of that of Method B.
For the method of the present invention, increase and loss filaments (gain
The number of ed and lost filaments) was 0 per 100,000 pounds of yarn. On the other hand, Method A was 3 and Method B was 2. Increase and loss filaments are two times more than desired with one yarn without conductive filaments, where the conductive filaments of one combined yarn traveling adjacent to each other on the equipment move to the other yarn. Occurs when leaving another yarn with the conductive yarn of
Static protection of carpets from the yarn of the invention (static
protection level [AATCC Text Method 134-1979 version
n) shuffle voltage (shuffle voltag
e)] was about the same as that of Methods A and B (about 2 KV to 3 KV) even though the conductive filament was stretched 3.26 times with the non-conductive filament.

This is surprising in view of the teachings of U.S. Pat. No. 4,085,182, column 1, lines 24-25, and column 2, lines 15-17.

The new method of the present invention achieves sufficient antistatic levels and reduces the consumption of expensive conductive fibers.

[Brief description of drawings]

FIG. 1 is a schematic view of a preferred method for producing a conductive yarn used in the method of the present invention, and FIG. 2 is a schematic view of the method of the present invention.

Claims (4)

[Claims] 1. A plurality of non-conductive nylon filaments are melt-spun in a cooling cylinder, and a spin-oriented conductive two-component filament is introduced into the newly spun thread line in the cooling cylinder by air action to form a combination. A process for producing a carpet yarn having reduced charging properties, characterized in that the woven yarns are combined in a pulling roll, the combined yarns are stretched and co-bulked, and then the yarns are wound. 2. A conductive two-component filament comprises a synthetic thermoplastic fiber-forming polymer enclosing 50% or more of a conductive core component, the conductive core component comprising a synthetic thermal carbon black dispersed therein. The method of claim 1 comprising a plastic polymer. 3. The method of claim 2 wherein the component surrounding the core is nylon. 4. A process according to claim 1, wherein the two-component filament is introduced in an amount of 1 to 10% by weight of the combined yarn.