US3819402A - Process for heat setting crimped synthetic polymeric fiber tow - Google Patents
Process for heat setting crimped synthetic polymeric fiber tow Download PDFInfo
- Publication number
- US3819402A US3819402A US00167156A US16715671A US3819402A US 3819402 A US3819402 A US 3819402A US 00167156 A US00167156 A US 00167156A US 16715671 A US16715671 A US 16715671A US 3819402 A US3819402 A US 3819402A
- Authority
- US
- United States
- Prior art keywords
- electromagnetic field
- finish
- heat
- heat setting
- load
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title claims abstract description 27
- 239000000835 fiber Substances 0.000 title claims description 33
- 238000009998 heat setting Methods 0.000 title claims description 20
- 230000001976 improved effect Effects 0.000 claims abstract description 19
- 239000000203 mixture Substances 0.000 claims description 21
- 229920000728 polyester Polymers 0.000 claims description 19
- 239000000470 constituent Substances 0.000 claims description 7
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims description 6
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 claims description 6
- -1 alkyl ethoxy potassium phosphate Chemical compound 0.000 claims description 5
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims description 4
- 229910001629 magnesium chloride Inorganic materials 0.000 claims description 3
- 235000011147 magnesium chloride Nutrition 0.000 claims description 3
- 235000010288 sodium nitrite Nutrition 0.000 claims description 3
- 229910052938 sodium sulfate Inorganic materials 0.000 claims description 3
- 235000011152 sodium sulphate Nutrition 0.000 claims description 3
- 150000008051 alkyl sulfates Chemical class 0.000 claims description 2
- 230000005672 electromagnetic field Effects 0.000 abstract description 45
- 239000000463 material Substances 0.000 abstract description 44
- 239000000758 substrate Substances 0.000 abstract description 31
- 238000010438 heat treatment Methods 0.000 abstract description 25
- 239000004753 textile Substances 0.000 abstract description 21
- 230000000694 effects Effects 0.000 abstract description 19
- 150000008040 ionic compounds Chemical class 0.000 abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 14
- 238000001035 drying Methods 0.000 description 6
- LWIHDJKSTIGBAC-UHFFFAOYSA-K tripotassium phosphate Chemical compound [K+].[K+].[K+].[O-]P([O-])([O-])=O LWIHDJKSTIGBAC-UHFFFAOYSA-K 0.000 description 6
- 125000000129 anionic group Chemical group 0.000 description 5
- 125000002091 cationic group Chemical group 0.000 description 5
- 150000002500 ions Chemical class 0.000 description 5
- 239000004615 ingredient Substances 0.000 description 4
- 229920001059 synthetic polymer Polymers 0.000 description 4
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 3
- 125000000217 alkyl group Chemical group 0.000 description 3
- 239000004202 carbamide Substances 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000003989 dielectric material Substances 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 229910000160 potassium phosphate Inorganic materials 0.000 description 3
- 235000011009 potassium phosphates Nutrition 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 239000004952 Polyamide Substances 0.000 description 2
- VMHLLURERBWHNL-UHFFFAOYSA-M Sodium acetate Chemical compound [Na+].CC([O-])=O VMHLLURERBWHNL-UHFFFAOYSA-M 0.000 description 2
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- BPAJPSFKPVRGCX-UHFFFAOYSA-N diethyl sulfate;4,5-dihydro-1h-imidazole Chemical compound C1CN=CN1.CCOS(=O)(=O)OCC BPAJPSFKPVRGCX-UHFFFAOYSA-N 0.000 description 2
- 235000013305 food Nutrition 0.000 description 2
- 230000020169 heat generation Effects 0.000 description 2
- 229920002239 polyacrylonitrile Polymers 0.000 description 2
- 229920002647 polyamide Polymers 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 229920000098 polyolefin Polymers 0.000 description 2
- 239000001632 sodium acetate Substances 0.000 description 2
- 235000017281 sodium acetate Nutrition 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920002994 synthetic fiber Polymers 0.000 description 2
- 239000008399 tap water Substances 0.000 description 2
- 235000020679 tap water Nutrition 0.000 description 2
- IFCOMSZHIDTXOT-UHFFFAOYSA-N 4,5-dihydro-1h-imidazole;sulfuric acid Chemical compound C1CN=CN1.OS(O)(=O)=O IFCOMSZHIDTXOT-UHFFFAOYSA-N 0.000 description 1
- 208000000044 Amnesia Diseases 0.000 description 1
- 208000031091 Amnestic disease Diseases 0.000 description 1
- 229920000742 Cotton Polymers 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000006986 amnesia Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 238000002788 crimping Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000005445 natural material Substances 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000005022 packaging material Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 239000002964 rayon Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000004758 synthetic textile Substances 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
- 229920001897 terpolymer Polymers 0.000 description 1
- 238000009988 textile finishing Methods 0.000 description 1
- 210000002268 wool Anatomy 0.000 description 1
Images
Classifications
-
- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
- D06M10/00—Physical treatment of fibres, threads, yarns, fabrics, or fibrous goods made from such materials, e.g. ultrasonic, corona discharge, irradiation, electric currents, or magnetic fields; Physical treatment combined with treatment with chemical compounds or elements
- D06M10/006—Ultra-high-frequency heating
Definitions
- Another object of the present invention is to provide an improved process for the heat setting of synthetic polymers under the effects of an oscillating electromagnetic field.
- the process of the present invention may thus be utilized for the heating of textile materials either as piece goods or in a continuous manner as in a process line.
- the process of the present invention is ideally suited for the heat setting of textile materials containing or consisting of high molecular weight syn- .thetic polymeric materials such as polyester fibers or filaments.
- the process of the present invention is further suited for generating heat in a material suitable for the bonding of lamina to form a laminate; heat sealing of plastics; for the application, drying, or curing of textile finishing compositions, coatings, films and the like.
- a preferred use of the process of the present invention is to heat set wet crimped polyester fiber tow which is measured by resulting shrinkage of the fiber in hot air or water.
- the present process willbe hereinafter described with relation to heat setting of polyester filament tow, though the principals alluded to equally apply for conventional drying or other heat treatment of the materials and substrates hereinbefore mentioned.
- Ionic finishes suitable for application to polyester filaments may be anionic or cationic in nature and further the ionic constituent may be an organic or inorganic compound.
- suitable ionic compounds that may be added to the fiber finishes and applied to the filaments include, but are not limited to, sodium nitrite, magnesium chloride, sodium sulphate, Parastat C-2, a cationic diethyl sulfate imidazoline, produced by Trylon Chemical, lnc., Mauldin, South Carolina and Tryfac 525K, an alkyl ethyoxy potassium phosphate, produced by Trylon Chemical, Inc., Mauldin, South Carolina.
- Results from Table 1 thus show ionic compounds, both organic and inorganic, as contributory to improved heat setting of polyester fibers under the effects of an oscillating electromagnetic field.
- Low fiber shrinkage is evidence that the fiber underwent sufficient heating to set the molecular structure of the fibers in the crimped state.
- An acceptable residual shrinkage for the particular polyester fiber treated is in the neighborhood of 6 per cent or less.
- Examples 2l6 dramatically illustrate the improvement obtained by adding an ionic compound to a the finish. By so doing, the proper heat setting may take place in the RP. oven and conventional drying can be avoided thereby.
- Stretch line speed can therefore be TABLE I EFFECTS OF IONIC FINISHES ON POLYETHYLENE TEREPHTHALATE FIBER SHRINKAGE EXAMPLE FINISH SPECIFICATION CURRENT FIBER SHRINKAGE NO. IN OVEN AFTER TREATMENT Component Solids Conc. Conductivity millimhos/cm amps 1 Demineralized H O 0.0 0.003 1.1 21.1 2 Urea 0.39 0.0387 1.1 18.4 3 NaNo 0.044 1.347 1.5 8.9 4 do. 0.020 0.449 1.95 5 .3 5 do. 0.044 0.587 1.6 6.1 6 do. 0194 2.034 1.95 3.6 7 do.
- Parastat C-Z is a cationic diethyl sulfate imidazoline.
- FIG. 1 A plot of relative loss factor for ionic compositions versus fiber shrinkage in hot air at 392F. is shown in FIG. 1.
- the solid line drawn through the points clearly indicates a definite correlation between loss factor of the finish and heat effect on the fiber load.
- Table I the experimental data of Table I is reinforced by the analytical data of Table II to definitely relate the loss factor of the finish at the operating frequency to the heating effect on a load subjected to an oscillating electromagnetic field.
- An improved process for continuously heat setting high molecular weight synthetic polymeric fiber tow comprising the steps of:
- finish composition a finish composition onto said tow, said finish composition having a relative loss factor of at least about 300 when measured at room temperature and 15 megahertz;
- Parastat O2 is a cationic dicthyl sulfate imidazoline.
- l'ryfac 525K is an anionic alkyl potassium phosphate.
- lar weight synthetic polymeric fiber tow as defined in claim 1 wherein the tow is a polyester fiber tow.
- composition contains anionic constituent selected from the group consisting of sodium nitrite, magnesium chloride, sodium sulfate, an alkyl sulfate imidazoline and an alkyl ethoxy potassium phosphate.
Landscapes
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Chemical Or Physical Treatment Of Fibers (AREA)
Abstract
An improved process is disclosed for the heating or heat treatment of a substrate, particularly a textile material in an oscillating electromagnetic field. The addition of ionic compounds to the material to be heated greatly enhances the heating or heat treatment of the material when subjected under proper moisture conditions to the effects of an oscillating electromagnetic field.
Description
United States Patent 1191 Thrower, Jr.
[ PROCESS FOR HEAT SETTING CRIMPED SYNTHETIC POLYMERIC FIBER TOW [75] Inventor: Herbert T. Thrower, Jr.,
Spartanburg, 8.0.
[73] Assignee: Hystron Fibers Incorporated,
Spartanburg, SC.
[22] Filed: July 29, 1971, [21] Appl. No.: 167,156
[52] US. Cl. 117/931 DH, 57/157 TS, 34/1, 1l7/l38.8 F, 117/1395 CF, 117/1395 co, 219/1061 51 111 ,01. B06111 1 1/11 1, H05b 9/00 [58] Field of Search. .ll 7/93 ,1 on, 139,511, 138.8 F, 117/1395 CF, 139.5WCQ;734 /1; 162/192;219/10.61; 57/157 TS [56] References Cited UNITED STATES PATENTS 2,473,251 6/1949 Hsu l17/93.I DH
5 16 X Z 5 12 U) 0! L 8 CD I 1111 3,819,402 June 25, 1974 2,618,796 11/1952 Brophy l17/93.1 DH 2,730,481 l/l956 Day 1l7/93.l DH 2,865,790 12/1958 Baer 117/93,] DH
OTHER PUBLICATIONS Von Hippel, Dielectric Materials and Applications, John Wiley & Sons Inc., New York, p. 361, (1954).
Primary Examiner-William D. Martin Assistant Examiner-John H. Newsome Attorney, Agent, or Firm-Wellington M. Manning, Jr.
[ 5 7] ABSTRACT 3 Claims, 1 Drawing Figure RELATIVE LOSS FACTOR OF FINISH, KIIX 1o" EFFECT OF LOSS FACTOR OF FINISH 0N HOT AIR SHRINKAGE OF FIBER HEAT-SET IN AN OSCILLATING ELECTROMAGNETIC FIELD PAIENIED 3. B 1 9,402
2 I6 g I2 U) g 8 1/ 3 RELATIVE LOSS FACTOR OF FINISH, KX IO EFFECT OF LOSS FACTOR OF FINISH ON HOT AIR SHRINKAGE OF FIBER HEAT-SET IN AN OSCILLATING ELECTROMAGNETIC FIELD INVENTOR. HERBERT T. THROWER,JR.
ATTORNEY BACKGROUND OF THE INVENTION The use of an oscillating electromagnetic field for the heat treatment of various and sundry materials has long been known. Depending upon the particular material or load being treated, numerous variations and modifications have been made to the apparatus for creating the electromagnetic field, to the design of equipment for a particular application of the electromagnetic field, preconditioning of the material to be subjected to the electromagnetic field, and the like. Oscillating electromagnetic fields have been employed to dry paper, textiles, foods, and the like; to heat set textiles; to treat packaging materials; for moisture leveling; and other wide and varied uses.
More particularly, the application of an oscillating electromagnetic field to the various products may involve an arrangement of apparatus whereby opposite plates or grids are provided in parallel or angular relationship with the load to be treated passing therebetween. Likewise, rods may be positioned in a side by side relationship with the material passing adjacent thereto or parallel rods may be deployed side by side and apart from each other in opposite banks with the material passing therebetween. Depending upon the particular product being subjected to the effects of the field, one of the above referred to arrangements could be employed.
Numerous variations have been made in the use of oscillating electromagnetic fields for the treating or drying of paper, textiles, food and the like. For example, substantial work has been conducted on the particular arrangement of the field producing apparatus. Such work was superficially mentioned above wherein opposite plates or grids, side by side rods or opposite banks of side by side rods have been used. Additionally, it has been found by some that a particular end result may be obtained by varying the attitude of the load (the material being treated) with respect to the electromagnetic field. As such, the load could be physically arranged to maintain a particular relationship to the geometry of the electric field. Moreover, frequency variations have been found to be useful in drying where it has been stated that as the moisture content of the load becomes lower, the frequency should be increased to continue to remove a desired amount of moisture. In certain cases, the oppositely positioned plates are angled in at one end, toward each other whereby the voltage gradient increases with the decreasing space between the plates. It has further been stated that certain conditioning of the load prior to exposure to the electromagnetic field will achieve a certain end result.
Generally speaking, the prior art has been quite inconsistent in the theoretical aspects of preconditioning of a substrate prior to passage through an oscillating electromagnetic field for the heating or otherwise treating of the substrate. For example, statements have been made in the prior art to the effect that the dielectric. constant of a material appliedto a load and subjected to an oscillating electromagnetic field is completely determinative of the improved heating of the load in the field. Further. statements have been made that relate a material having a high dielectric constant to also having a high loss factor to thus improve drying, etc. of a load under the effects of an oscillating electromagnetic field. Voltage variation across the electrodes that are utilized to create the electromagnetic field has also been taught to afford improvement. Hence, as a mate- 5 rial loses moisture, its power factor decreases thus necessitating a higher voltage to maintain a relatively uniform effect on the material. Dipole moment of a material used to finish a textile substrate has also been stressed as an important factor in improved effects on the substrate in oscillating electromagnetic fields. For example, one source stated that a material having a high dipole moment, such as water, experiences extreme molecular vibration in accord with the rapidly reversing polarity of the electrodes, thereby creating increased heat on the load.
All of the above statements prior to a vast amount of work that has been done in the field of oscillating electromagnetic energy for industrial or other use. The present invention is still a further advance in this particular art, and teaches an improved process for the heating or otherwise heat treating of substrates, particularly textile materials by the addition of certain ionic ingredients thereto.
While the prior art is quite sizeable and contains teachings pertinent to the heating of materials in an oscillating electromagnetic field, there is no teaching or suggestion in the prior art of the present invention. The prior art is exemplified by U.S. Pat. No. 2,390,572 to Brabander; U.S. Pat. No. 2,503,779 to Story; U.S. Pat. No. 2,530,680 to Burkholder; U.S. Pat. No. 2,709,856 to Hunter et al; U.S. Pat. No. 3,205,334 to Manwaring; U.S. Pat. No. 3,292,270 to Spunt; U.S. Pat. No. 3,399,460 to Russell; U.S. Pat. No. 3,435,534 to Knobloch et al; U.S. Pat. No. 3,484,179 to Adams et al; U.S. Pat. No. 3,485,984 to Cerutti and U.S. Pat. No. 3,531,551 to McDonough and British patent 1,009,586 to L & L'Manufacturing, lnc.
SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved process for the heating of textile materials in an oscillating electromagnetic field.
Another object of the present invention is to provide an improved process for the heat setting of synthetic polymers under the effects of an oscillating electromagnetic field.
Still another object of the present invention is to provide an improved process for the heat treatment of a dielectric material in an oscillating electromagnetic field.
Another object of the present invention is to provide an improved process for the heat treating of synthetic polymeric fibers in an oscillating electromagnetic field.
at least 4 per cent based on dry weight of the substrate.
Textile materials that may be treated by the process of the present invention include, but are not limited to filament, yarn, tow, staple, nonwoven, knit, woven, etc.
substrates. Furthermore, the textile material may be a natural material, a synthetic polymer or a combination of the two. Exemplary of suitable synthetic polymeric materials that may also be treated according to the present invention are polyesters, polyamides, polyolefins, polyacrylonitriles and the like.
The process of the present invention may thus be utilized for the heating of textile materials either as piece goods or in a continuous manner as in a process line. Furthermore, the process of the present invention is ideally suited for the heat setting of textile materials containing or consisting of high molecular weight syn- .thetic polymeric materials such as polyester fibers or filaments. The process of the present invention is further suited for generating heat in a material suitable for the bonding of lamina to form a laminate; heat sealing of plastics; for the application, drying, or curing of textile finishing compositions, coatings, films and the like.
. Moreover, the process of the present invention may be controlled in such a manner to heat a substrate without causing damage to the substrate and in particular to heat a textile material having a particular finish thereon to remove a carrier from the finish without activating other ingredients of the finish as might be required prior to curing a textile resin, for example, for permanent press applications or even curing the textile resin, if desired.
The present invention is thus directed to the addition of ionic materials in a carrier such as water to amaterial to be treated in an oscillating electromagnetic field. Ionic materials having a high loss factor in the particular operating frequency improve heat conversion in the electromagnetic field. These ionic materials may be cationic, anionic, or may be of an organic or inorganic nature.
The operating frequency range of the oscillating electromagnetic field can be set as desired. It has been determined, however, that the process of the present invention performs best at lower frequencies. Accordingly, an operating frequency for the oscillating elec tromagnetic field is preferred in a range up to about 300 megahertz.
BRIEF DESCRIPTION OF THE DRAWING The FIGURE is a graphical presentation of the effect of loss factor of a finish composition on residual shrinkage of a heat treated polyester fiber.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS The process of the present invention is suitable for the heating of numerous substrates, particularly textile substrates including both natural and synthetic textile materials. For example, cotton, wool and rayon exemplify natural textile materials. Polymers, copolymers, terpolymers, etc. containing polyesters, polyamides, polyolefins, polyacrylonitriles, and the like including the possible modifications thereto, typify synthetic polymers that may be treated by the present process. Additionally, blends of natural and synthetic material may likewise be treated. Insofar as the type of substrate, per se is concerned, the process of the present invention may be advantageously utilized for fibers, yarns, staple, tow, fabrics, garments, films, coatings, laminates and the like.
strued to include the removal of moisture from a load,
heat setting of the load or portions thereof, curing of a load or the like. In fact, a preferred use of the process of the present invention is to heat set wet crimped polyester fiber tow which is measured by resulting shrinkage of the fiber in hot air or water. As such, the present process willbe hereinafter described with relation to heat setting of polyester filament tow, though the principals alluded to equally apply for conventional drying or other heat treatment of the materials and substrates hereinbefore mentioned.
A finish containing a certain amount of the active ionic ingredient is applied to the textile material, in this case, a polyester filament tow which is to be heat set. Preferably, the finish composition will be applied in an aqueous mixture though numerous other carriers or bases may be utilized to obtain the same or similar results. The textile material having the particular improved finish thereon is passed through an oscillating electromagnetic field under proper moisture conditions where improved heat setting of the polyester filaments takes place. In the sense of application of the finish to the substrate, in general, the ionic constituent may be applied to the textile material at any point prior to treatment in the oscillating electromagnetic field, provided that, prior to treatment in said field, the substrate has a proper moisture content. Hence, the ionic compound may be applied in an aqueous composition, may be incorporated into the polymer, may be added in a paste, semi dry or dry state or the like. Thereafter, if the substrate does not contain the proper moisture content, moisture must be added to achieve same. Likewise, the ionic constituent may be included in a stretch finish bath or the like either alone or with other constituents as might be desirable for a particular result.
Moisture conditions according to the teachings of the present invention are an important variable in the process. A dry substrate, one having an initial moisture content below about 4 per cent by weight, will not perform satisfactorily according to the teachings of the present invention. It is thus necessary to present the substrate to the electromagnetic field, at a moisture content of at least about 4 per cent by weight of the substrate. Preferably, the moisture content of the substrate should be at least about 7.5 per cent by weight of the substrate. Beyond about 20 per cent moisture based on the weight of the substrate, however, the improved effects became uneconomical due to the cost of moisture removal. As such, after application of the finish, the moisture content should preferably be con-' trolled in the range of about 4 to about 20 per cent based on the weight of the substrate. Thus liquid may be added to the substrate or expelled from the substrate prior to subjecting the substrate to the oscillating electromagnetic field. Moisture as referred to herein in-' cludes any liquid carrier that is compatible with both the ionic compound and the substrate without adverse effects thereto, and that can be removed by the electromagnetic field. r
The ionic materials added to the substrate to bring about the improved heating conditions according to the teachings of the present invention should yield a finish composition having a higher relative loss factor than that of water. Much of the prior art refers to water as being the key to success of electromagnetic fields with out any definition as to the particular water being used. Demineralized water for example gives no effect whatsoever, though much of the prior art credits water as the active component for improved heating. It can be hypothesized that the water being used according to the prior art contained a certain ion concentration such that some effect was obtained. Such is, however, far from a teaching of the present invention. Tap water varies considerably from one area to another. Moreover, tap water in the same area will vary considerably in ion content at different times of the year. Hence what might improve the effects of an oscillating electromagnetic field at one time of the year will have little or no effect at a different time of the year. The present invention has now precisely determined the active ingredients that improve the heating effects on a substrate in an oscillating electromagnetic field. With the teachings set forth herein, one can now completely and consistently control the improved heating to realize an anticipated result.
it has been determined that ionic materials having a high loss factor at the operating frequency of an oscillating electromagnetic field improve the heating effects of the field when added to a material being subjected to the field.
Theoretically, the heating in an oscillating electromagnetic field is predicated upon the ability of the load to convert available electrical energy into heat. Moreover, a load placed between the plates of a radio frequency generator may be considered analogous to a capacitor and resistor in paralleL'Current flowing through the capacitor is considered as charging current and current through the resistor is considered as loss current. The loss current is that portion that is converted into heat. Total current flow in the field may thus be defined according to Von Hippel, Dielectric Materials and Applications, pp 3, 4. M.l.T. Press (1954), as
l total l charging l loss where:
1 total total electrical current through the electromagnetic field l charging charging current component that leads by a temporal phase angle of 90 l loss loss current component in phase with voltage j= a complex algebra vector operator w angular frequency of applied current C capacitance of the load C capacitance of free space G reciprocal of load resistance V applied voltage e permittivity of the load e, permittivity of free space e'/e,, relative permittivity k v Total current flow may thus further be defined as 1 total jwk*C0V relative dielectric constant e'/e tan 5 loss tangent or dissipation factor 1 loss loss current component in phase with voltage l total (/wk' w COV (8 Hence, comparing equations 3 and 8, it is seen that the product of the loss factor and the frequency, called the dielectric conductivity, determines the amount of electrical energy that is transformed into heat. To increase the heating of a load under the effects of an electromagnetic field operating at a set frequency, the loss factor associated with the load should thus be increased. Further, depending upon the magnitude of the operating frequency, the loss factor of a material has been found to be substantially independent of its dielectric constant.
Ionic finishes suitable for application to polyester filaments according to the teachings of the present invention may be anionic or cationic in nature and further the ionic constituent may be an organic or inorganic compound. Examples of suitable ionic compounds that may be added to the fiber finishes and applied to the filaments include, but are not limited to, sodium nitrite, magnesium chloride, sodium sulphate, Parastat C-2, a cationic diethyl sulfate imidazoline, produced by Trylon Chemical, lnc., Mauldin, South Carolina and Tryfac 525K, an alkyl ethyoxy potassium phosphate, produced by Trylon Chemical, Inc., Mauldin, South Carolina. Each of the compounds listed above, when added to polyester filaments in an aqueous finish composition, brought about a noticeably improved heating of polyester filaments to the point of heat setting the previously crimped filaments. in addition to the ionic compounds applied to the textile substrate, other ingredients may be simultaneously applied therewith. For example, a normal finish for a synthetic polymeric fiber or filament may include not only the ionic constituent therein, but also dyestuffs, antistats, lubricants and other finishing compounds such as textile resins and the like. Also, as mentioned above, while the composition is preferably an aqueous composition, other liquid carriers may be employed.
The presence of the ionic compound in the finish improves the conversion of electrical energy into heat whereby the previously crimped filaments are heat set. The degree of heat setting is evidenced by the per cent fiber shrinkage in hot air at 392F. A low per cent shrinkage indicates good heat setting. It has been shown that an ionic material containing composition having a high relative loss factor measured at room temperature and a frequency of 15 megahertz will, when added to a load, improve the conversion of electrical energy into heat when the load is passed through an oscillating electromagnetic field. The degree of heating of the load may thus be empirically predicted by control of ion concentration in the finish composition, operating frequency of the oscillating electromagnetic field, voltage gradient across the field and moisture content of the load.
Though as mentioned above, a relative loss factor greater than water shows improvement, it is preferred according to the teachings of the present invention that the composition applied to the load have a relative loss factor of at least about 300 when measured at room temperature and 15 megahertz. A finish composition having a relative loss factor of at least about 300 at the previously mentioned conditions converts sufficient electrical energy into heat to heat set the previously crimped polyester filaments. Temperatures significantly higher than 212F. are generally required for suitable heat setting of polyester filament tows, and though an aqueous finish composition has been used predominantly, it is hypothesized that as water is evaporated, the concentration of ions increases to thus raise the boiling point of the remaining aqueous medium. As such, the higher heat setting temperatures are reached in the field. It is not intended, however, that the present invention be limited to this theory.
Addition of ionic compoundstoa finish increases the electrical conductivity of the finish. Hence, sufficient ionic material should be added to the finish to permit conductance of the electrical energy to be converted into heat. There is not, however, a direct relationship between finish conductivity and heat generation in the electromagnetic field. Instead, for each particular system, there is a level of conductivity at which sufficient current may pass and beyond which, increases in conductivity though helpful, are not appreciably additive towards further heat generating capability. Beyond about 0.4 millimhos per centimeter, for example, a higher ion concentration will not appreciably add to the heat generation capability in the electromagnetic field. Also, high conductivity in a finish having a low relative loss factor will not perform satisfactorily according to the teachings of the present invention. riieo seiaiifigfreqtifieyafifi electromagnetfifild is a further important consideration. Improved effects due to the addition of ionic materials to the load should be noticed at any operating frequency. The greatest improvement has been noticed, however, in the lowerfrequency range of the spectrum. Hence, an electromagnetic field oscillating at a frequency of up to about 300 megahertz is preferred for practice of the process of the present invention. A frequency range of from about 0.1 to about 30 megahertz is further preferred. The lower frequency level is more economical and more effective during operation.
Voltage gradient across the electromagnetic field must also be considered for the process can be rendered unsuccessful by use of an incorrect voltage gradicut for the particular material being treated. Too high a voltage gradient or inadequate vapor removal capacity for example, can cause arcing between the electrodes which will deactivate the field producing generator. Hence, a proper voltage gradient for a particular system (load and finish) should be that gradient as high as possible without causing arcing across the electrodes. Such a condition cannot be numerically expressed due to the large variance in materials that may be treated and ionic compounds being used. Likewise, there is great divergence in the expected end result. For the heat setting of high molecular weight synthetic polymer fibers and filaments, a voltage gradient in the range of from about 0.2 to about 5.0 kilovolts per centi-' meter spacing between the electrodes is preferred.
Having discussed parameters of the present invention, the following examples are submitted to more fully describe the specifics of the invention and to permit a better understanding thereof.
quency oven, Model HFV60, manufactured by Siemens, AG, Erlangen, Germany, and passed therethrough at a rate sufficient to permit a residence time of 65 seconds in the oven. Plates in the oven were set at a gap of 13 centimeters at entrance and tapered to a 9 centimeter gap at exit. Applied voltage was 15,000 volts and operating frequency was 15 megahertz. Measured current through the oven was 1.1 amps. The tow entering the oven exhibited a moisture content of 6 per cent by weight and a fiber shrinkage of 22 per cent in hot air at 392F. Samples were taken from the tow at the exit end of the oven and analyzed for shrinkage in hot air at 392F. Hot air shrinkage of the filament samples averaged 21.1 per cent. Hence, though some of the water may have been removed from the tow during passage of the tow through the oven, the tow was still moist to the touch and the 21.1 per cent shrinkage in hot air after passage through the ovenindicated virtually no heat setting of the crimped filaments. Data and results from Example I are reported in Table I.
" amnesia Example I was repeated under identical conditions except for finish composition. In Examples 2-16, various organic and inorganic ionic compounds were added to a finish which was applied to the tow prior to stretching in steam. Data and results from Examples 2-16 are set forth below in Table I. 7 W
Normal shrinkage for this particular polyester fiber is in the range of 20 to 22 per cent. From Table I, it can readily be seen that low fiber shrinkage and thus good heat setting was achieved when certain ionic compoundswere added to the finish. Note, however, although urea has a high dipole moment, it has a relatively low loss factor and thus performed only slightly better than demineralized water. Also note that arcing occurred when sodium acetate was added. The arcing was presumed to be due to rapid decomposition of the sodium acetate, yielding conductive vapor betweenthe electrodes. Aluminum sulfate also showed only a slight improvement over demineralized water. As can be seen below, both aluminum sulfate and urea solutions were analyzed to have relatively low loss factors.
Results from Table 1 thus show ionic compounds, both organic and inorganic, as contributory to improved heat setting of polyester fibers under the effects of an oscillating electromagnetic field. Low fiber shrinkage as mentioned above, is evidence that the fiber underwent sufficient heating to set the molecular structure of the fibers in the crimped state. An acceptable residual shrinkage for the particular polyester fiber treated is in the neighborhood of 6 per cent or less. Hence, Examples 2l6 dramatically illustrate the improvement obtained by adding an ionic compound to a the finish. By so doing, the proper heat setting may take place in the RP. oven and conventional drying can be avoided thereby. Stretch line speed can therefore be TABLE I EFFECTS OF IONIC FINISHES ON POLYETHYLENE TEREPHTHALATE FIBER SHRINKAGE EXAMPLE FINISH SPECIFICATION CURRENT FIBER SHRINKAGE NO. IN OVEN AFTER TREATMENT Component Solids Conc. Conductivity millimhos/cm amps 1 Demineralized H O 0.0 0.003 1.1 21.1 2 Urea 0.39 0.0387 1.1 18.4 3 NaNo 0.044 1.347 1.5 8.9 4 do. 0.020 0.449 1.95 5 .3 5 do. 0.044 0.587 1.6 6.1 6 do. 0194 2.034 1.95 3.6 7 do. 0.44 4.738 1.8 3.1 8 NaAc 0.53 0.042 Arcing 18.3 9 MgCl, 0.66 4.389 1.95 2.1 w mas n. 9-64 90.35 1-2 1 l Nil-2S0. 0.046 0.542 1.9 5.6 12 Parastat C-2 3.2 0.570 1.9 3.2 13 do 1.0 1.211 1.75 5.9 14 Parastat C-2 1.0 0.287 1.8 6.2 15 Tryfac 525K 1 0 3.323 1.7 6.1 16 Tryfac 525K 5 0 2.412 1.8 g 5.3
V 1 Fiber shrinkage measured in hot air at 392F. 2 Parastat C-Z is a cationic diethyl sulfate imidazoline. Tryfac 525K is an anionic alkyl potassium phosphate. pH= 5.0
increased substantially over conventional dryers" and also over a conventional dryer in tandem with a radio frequency oven. Moreover, power consumption of the radio frequency oven is low compared to conventional heat setting of the polyester fibers.
EXAMPLE I? 4 dure was used to measure the dielectric properties of 5 the solutions. Tabulated data and results of the analyses. are presented in Table II below. Also for comparative purposes, the fiber shrinkage data from Table l is reproduced beside the appropriate materials. 50
TAELE II A plot of relative loss factor for ionic compositions versus fiber shrinkage in hot air at 392F. is shown in FIG. 1. The solid line drawn through the points clearly indicates a definite correlation between loss factor of the finish and heat effect on the fiber load. Hence, the experimental data of Table I is reinforced by the analytical data of Table II to definitely relate the loss factor of the finish at the operating frequency to the heating effect on a load subjected to an oscillating electromagnetic field.
Having described the present invention in detail, it is obvious that one skilled in the art will be able to make variations and modifications thereto without departing from the scope of the invention. Accordingly, the scope of the present invention should be determined only by the claims appended hereto.
What is claimed is:
1. An improved process for continuously heat setting high molecular weight synthetic polymeric fiber tow comprising the steps of:
a. applying a finish composition onto said tow, said finish composition having a relative loss factor of at least about 300 when measured at room temperature and 15 megahertz;
b. crimping said tow; and
RELATIVE LOSS FACTOR FOR SPIN FINISHES Fiber shrinkage measured in hot air at 392F. Parastat O2 is a cationic dicthyl sulfate imidazoline. l'ryfac 525K is an anionic alkyl potassium phosphate.
lar weight synthetic polymeric fiber tow as defined in claim 1 wherein the tow is a polyester fiber tow.
3. The process as defined in claim 1 wherein the composition contains anionic constituent selected from the group consisting of sodium nitrite, magnesium chloride, sodium sulfate, an alkyl sulfate imidazoline and an alkyl ethoxy potassium phosphate.
Claims (2)
- 2. An improved process for heat setting high molecular weight synthetic polymeric fiber tow as defined in claim 1 wherein the tow is a polyester fiber tow.
- 3. The process as defined in claim 1 wherein the composition contains an ionic constituent selected from the group consisting of sodium nitrite, magnesium chloride, sodium sulfate, an alkyl sulfate imidazoline and an alkyl ethoxy potassium phosphate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00167156A US3819402A (en) | 1971-07-29 | 1971-07-29 | Process for heat setting crimped synthetic polymeric fiber tow |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00167156A US3819402A (en) | 1971-07-29 | 1971-07-29 | Process for heat setting crimped synthetic polymeric fiber tow |
Publications (1)
Publication Number | Publication Date |
---|---|
US3819402A true US3819402A (en) | 1974-06-25 |
Family
ID=22606166
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00167156A Expired - Lifetime US3819402A (en) | 1971-07-29 | 1971-07-29 | Process for heat setting crimped synthetic polymeric fiber tow |
Country Status (1)
Country | Link |
---|---|
US (1) | US3819402A (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4873605A (en) * | 1986-03-03 | 1989-10-10 | Innovex, Inc. | Magnetic treatment of ferromagnetic materials |
US5154969A (en) * | 1990-06-05 | 1992-10-13 | E. I. Du Pont De Nemours And Company | Bonded fibrous articles |
US5163771A (en) * | 1991-10-23 | 1992-11-17 | Bremer Paul W | Full engagement interlocking |
US5318650A (en) * | 1990-06-05 | 1994-06-07 | E. I. Du Pont De Nemours And Company | Bonded fibrous articles |
US6144544A (en) * | 1996-10-01 | 2000-11-07 | Milov; Vladimir N. | Apparatus and method for material treatment using a magnetic field |
US20040251919A1 (en) * | 2003-06-16 | 2004-12-16 | Siemens Vdo Automotive Corporation | Method of measuring the concentration of a fluid component that has a variable dielectric characteristic |
US20060103393A1 (en) * | 2004-11-17 | 2006-05-18 | Daniel Stahlmann | Sensor device for determining a fluid property |
US20060196264A1 (en) * | 2005-03-03 | 2006-09-07 | Siemens Vdo Automotive Corporation | Level sensor |
US20070056365A1 (en) * | 2005-08-08 | 2007-03-15 | Siemens Vdo Automotive Corporation | Fluid quality sensor |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2473251A (en) * | 1945-05-29 | 1949-06-14 | Gen Electric | High-frequency dielectric heating apparatus |
US2618796A (en) * | 1949-05-05 | 1952-11-25 | United Shoe Machinery Corp | Stiffening uppers of shoes |
US2730481A (en) * | 1952-10-29 | 1956-01-10 | Celastic Corp | Polymerization by dielectric heating using inorganic salts as heating assistants |
US2865790A (en) * | 1955-08-19 | 1958-12-23 | Carl A Baer | Method of treating fibrous material utilizing a radio-frequency field which extends predominantly at right angles to the length of said material |
-
1971
- 1971-07-29 US US00167156A patent/US3819402A/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2473251A (en) * | 1945-05-29 | 1949-06-14 | Gen Electric | High-frequency dielectric heating apparatus |
US2618796A (en) * | 1949-05-05 | 1952-11-25 | United Shoe Machinery Corp | Stiffening uppers of shoes |
US2730481A (en) * | 1952-10-29 | 1956-01-10 | Celastic Corp | Polymerization by dielectric heating using inorganic salts as heating assistants |
US2865790A (en) * | 1955-08-19 | 1958-12-23 | Carl A Baer | Method of treating fibrous material utilizing a radio-frequency field which extends predominantly at right angles to the length of said material |
Non-Patent Citations (1)
Title |
---|
Von Hippel, Dielectric Materials and Applications, John Wiley & Sons Inc., New York, p. 361, (1954). * |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4873605A (en) * | 1986-03-03 | 1989-10-10 | Innovex, Inc. | Magnetic treatment of ferromagnetic materials |
US5154969A (en) * | 1990-06-05 | 1992-10-13 | E. I. Du Pont De Nemours And Company | Bonded fibrous articles |
US5318650A (en) * | 1990-06-05 | 1994-06-07 | E. I. Du Pont De Nemours And Company | Bonded fibrous articles |
US5163771A (en) * | 1991-10-23 | 1992-11-17 | Bremer Paul W | Full engagement interlocking |
US6144544A (en) * | 1996-10-01 | 2000-11-07 | Milov; Vladimir N. | Apparatus and method for material treatment using a magnetic field |
US20040251919A1 (en) * | 2003-06-16 | 2004-12-16 | Siemens Vdo Automotive Corporation | Method of measuring the concentration of a fluid component that has a variable dielectric characteristic |
US20060103393A1 (en) * | 2004-11-17 | 2006-05-18 | Daniel Stahlmann | Sensor device for determining a fluid property |
US7902838B2 (en) | 2004-11-17 | 2011-03-08 | Continental Automotive Systems Us, Inc. | Sensor device for determining a fluid property |
US20060196264A1 (en) * | 2005-03-03 | 2006-09-07 | Siemens Vdo Automotive Corporation | Level sensor |
US20070056365A1 (en) * | 2005-08-08 | 2007-03-15 | Siemens Vdo Automotive Corporation | Fluid quality sensor |
US7466147B2 (en) | 2005-08-08 | 2008-12-16 | Continental Automotive Systems Us, Inc. | Fluid quality sensor |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3819402A (en) | Process for heat setting crimped synthetic polymeric fiber tow | |
US2365931A (en) | Finishing of polyamide fabrics | |
US3940533A (en) | Method of attaching metal compounds to polymer articles | |
AU659632B2 (en) | Powder coating method for producing circuit board laminae and the like | |
US2311080A (en) | Textile treatment | |
US3364294A (en) | Filament orientation process | |
US3001262A (en) | Process for making elastic textile materials | |
US3784355A (en) | Solvent dyeing or solvent creaseproofing with steam and solvent vapor drying | |
US4902562A (en) | Electrically conductive materials | |
US3551189A (en) | Solvent recovery process and apparatus | |
AU727965B2 (en) | Process for the antifelt finishing of wool with the aid of low-temperature plasma treatment | |
US3288553A (en) | Process for treating napped fabrics | |
US2438366A (en) | Drying of textile materials | |
US3983286A (en) | Method of fixing copper salts to articles of synthetic polymers | |
ES336317A1 (en) | Process, agent and article relating to improved adhesion between a shaped article of a crystalline polyester and rubber | |
US2184153A (en) | Manufacture of elastic fabrics | |
US3250641A (en) | Method of processing tire cords, tire cord fabric, and the like | |
US3656246A (en) | Method of making a durable press garment which may be conducted in the home | |
US3634126A (en) | Process for controlling location of composition in fabrics | |
WO2005038125A1 (en) | Dyeing process for textile matter and obtained dyed matter | |
US3846845A (en) | Process of curing chemically treated cellulosic fabric | |
US3435534A (en) | Process for continuously heating,drying and heat-setting tows of filaments of synthetic polymers | |
US2689806A (en) | Process for resin treating wool textile material | |
US3576661A (en) | Process and system for dewrinkling garments | |
Pai et al. | Radio frequency drying in the textile industry |