US3369981A - Method of treating textile materials of animal origin, notably wool - Google Patents

Description

Feb. 20, 1968 R. LEVAUX METHOD OF TREATING TEXTILE MATERIALS OF ANIMAL ORIGIN, NOTABLY WOOL Filed July 19, 1967 Uite States arent 3,369,981 METHOD OF TREATING TEXTILE MATERIALS OF ANIMAL ORIGIN, NOTABLY WOOL Robert Levaux, 21 Blvd. de Belgique, Monaco Continuation-impart of application Ser. No. 295,918, July 18, 1963. This application July 19, 1967, Ser. No. 654,474

Claims priority, application France, Aug. 16, 1962, 907,021, Patent 1,338,929; Apr. 22, 1963, 932,231, Patent 1,338,929

5 Claims. (Cl. 204-165) ABSTRACT OF THE DISCLOSURE Textile materials of animal origin, in the form of tibres, yarns or fabric are passed through a shower of sparks, in free atmosphere, between electrodes to which high voltage, high frequency current is applied with a suiciently low current intensity to assure a sutliciently low temperature to avoid any deterioration of the treated textile material. The treatment improves the general physical properties of the material including its spinning characteristics, washability and dyeability.

Cross-reference to related application This is a continuation-in-part of my patent application Ser. No. 295,918 filed on July 18, 1963, for Method and Apparatus for Treating Textile Materials and Products.

Background of the invention The present invention relates to a method of treating textile materials of animal origin, notably wool, with a view to modify their molecular and cellular structure.

A method of treating textile materials is already known wherein the material to be treated is submitted to the action of an electrical discharge in the form of brush or convective discharge in a rareied atmosphere. Such a method is described in the U.S. Patent No. 2,977,475. It requires the use of a vacuum bell and this obviously constitutes a drawback in the commercial application of the method.

Summary of the invention vtextile materials can be treated in the free atmosphere.

To this end, the method of treating textile materials of animal origin, notably wool, is characterized in that there is produced between two electrodes, inthe free atmosphere, a shower of sparks creating between these electrodes a temperature low enough to preclude any deterioration of the treated textile libres, and that the textile material is caused to pass through said spark shower.

With the method of this invention the properties of the treated textile materials are improved considerably.

From the point of view of spinning capacity the method of this invention affords a substantial increment in the coeicient of friction, or of the D.F.E, The increase in this coeicient entails an improvement in the spinning capacity, in the dynamometric strength of the yarns and in their elongation, a reduction in the number of breakings under spinning conditions, and it also permits the use of shorter wool fibres for producing a same article. Finally, the spark action causes a reduction in the static electricity at all stages of the manufacture.

The spark emission is attended by the production of a considerable quantity of negative electricity attracted in turn at high speed by the positive terminal of the ground connection. Thus, the negative electrons from the wool Fice are entrained and impart to the assembly the positive charge of the proton.

From the point of view of washability, the method of this invention permits of obtaining the same yarn shrinkage rate as that obtained in the case of unshrinkable treated yarns by applying conventional chemical processes, but without the known inconveniences characterizing these processes. It is also attended by a reduction in the felt-like appearance, without 'impairing the improvements in spinning capacity as mentioned hereinabove. It further reduces curling and permits of obtaining a neat appearance in the mesh or texture of the fabric.

From the point of view of dyeing, no specific cares are required for dyeing wool treated by the method of this invention, whether in worsted, spun or roll form, and the strength of the dyes will remain perfectly unaltered by daylight and washing, a feature seldom observed when the wool is submitted to non-shrink treatments by means of a conventional chemical process changing completely the -molecular structure of the wool.

Brief description of the drawing Now a typical form of embodiment of this invention will be described by way of example with reference to the attached drawing, in which:

FIGURE 1 is a wiring diagram of an apparatus for carrying out the method of this invention;

FIGURE 2 is a diagram showing an industrial plant for carrying out the method of this invention.

Description of the preferred embodiment The apparatus illustrated in the drawing comprises an A.C. generator 1 of any 4known and suitable type. The output of this generator 1 is connected to an electrode 2 constituting the receiving electrode, which registers with another electrode 3 referred to hereinafter as the etiiux electrode. The textile material to be treated (such as wool) is designated diagrammatically in the form of a web, strip or ribbon 4 travelling between the electrodes 2 and 3, under the control of feed rollers 5.

The A.C. voltage generated by the generator 1 is suf- Iicient to produce between the electrodes 2 and 3 a shower of sparks owing through the textile web 4 to be treated, the spark generation being attended by the production of ozone.

According to a specific but non-limiting form of embodiment of this apparatus the A.C. current fed across the electrodes 2 and 3 may be as high as, and even higher than, 100,000 volts and the frequency of the current may be of the order of 500 kHz. However, these values should not be construed as limiting the present invention for other frequency values may be used. On the other hand, the voltage must be greater than that necessary to produce a disruptive discharge in air between the electrodes 2 and 3.

The output current of generator 4 which has a very low intensity is channelled towards the receiving electrode 2. If it is desired to check the maximum strength of the current owing to the ground, the latter is connected directly to the out-put of generator 1 by interposing a milliammeter and eliminating all connections between this output and the receiving electrode 2. The current strength measured on the milliammeter dial is in the average only 35 milliamperes. This current strength may vary to a small extent and the best measurements gave 30 milliamperes.

The receiving electrode 2 may be constructed as Shown by way of example in the drawing, this form of embodiment being given of course -by way of illustration. A solid or perforated metal plate 2a is sandwiched Ibetween a glass plate 2b at the top and a mica-glass plate 2c at the bottom. This electrode 2 may be replaced by any other known device or arrangement giving similar results.

This electrode 2 must be capable of discharging itself at well-defined points and in a predetermined direction. To this end, the second or eiux electrode 3 is disposed parallel to the receiving electrode 2, and constructed for example as follows: a glass plate 3u is Supported by conducting metal tubes 3b (or solid metal rods), of copper, silver, bronze, aluminum, etc., these tubes or rods 3b being grounded.

This form of embodiment of the electrode 3 is not compulsory and a modification thereof may consist in replacing the straight tubes 3b with curved tubes or alternately the metal could be distributed under the glass plate 3a according to any suitable pattern. The tubes 3b may also `be replaced 'by a single metal plate, whether solid or hollow, covering the complete surface area of glass plate 3a.

According to a modified form of embodiment, in the efflux electrode 3 the insulating plate 3a may be replaced by a sheath also made of dielectric material and receiving the metal tubes 3b therein. In the case of tubes, these may be xed or rotatable.

The electrodes 2 and 3 may also consist of rotary cylinders associated by pairs and between which the textile material to `be treated in caused to travel. This arrangement, which is used in a commercial application, is illustrated diagrammatically in FIGURE 2. In this figure it will be seen that the textile web 4 travels `between several successive pairs of lower and upper cylinders 7, 8 rotatably mounted in a suitable frame structure. These cylinders 7 and 8 consist respectively of internal metal tubes 7a, 8a covered or lined with sheaths 7b, 8b of dielectric material. All'the metal tubes 7a of the lower cylinders 7 constituting in this case the receiving electrode 2 are connected in common to the output terminal of the A.C. generator 1, and all the metal tubes 8a of the upper cylinders constituting the etilux electrode 3 are grounded.

The receiving electrode 2, as well as the eiilux electrode 3, may be of plane, curved, spherical, corrugated or other configuration. In this case the two electrodes 2 and 3 must fit into each other, irrespective of their shape.

Under actual service conditions, two cases may arise:

(l) If straight tubes or rods are used, or if these are curved in a horizontal plane, the discharge takes place between the electrodes 2 and 3 and develops regular spark metal underlying the glass plate 3a (case shown in FIG- URE 1), or alternately these combs7 develop in the gaps left between each pair of cylinders 7 and 8 (FIGURE 2).

(2) If a solid or hollow plate covering the whole of the lower face of glass plate 3a is substituted for the tubes or rods, a spark shower is produced between the electrodes 2 and 3 and covers on the electrode 2 a surface area equal to that of the metal plate 2a sandwiched `between the dielectric plates of electrode 2.

The textile material to be treaated, which is in any desired form (worsted, carded, ribbons, fabric, yarns, knitted fabric), is fed through the gap formed between the electrodes 2 and 3 vby any suitable mechanical means. This textile material 4 travels between the electrodes and is pulled by a pair of rollers 5, adequate means being provided, if desired, for varying the feed rate. With this device a great flexibility is afforded as far as the residence time of the material between the electrodes is concerned, this residence time varying according to the nature of the treated material and to the desired nal properties thereof.

The output current of generator 1 is adjusted to keep the temperature between the electrodes 2 and 3 at a value lower than that likely to damage the treated material. In the specific case of the treatment of wool, for instance, the temperature between the electrodes 2 and 3 `should preferably not exceed 50 C. during the treatment, to avoid any damage to the material, if the exposure time ranges from about 30 to 60 seconds, `but temperature in excess of 100 C. may be used if the exposure time is less than 30 seconds. The temperature increment may constitute an advantageous factor.

The results of comparative tests carried out on samples of untreated wool and on identical samples treated according to this invention will now be illustrated. The following Table I clearly shows the improvements in properties such as spinning capacity and non-shrinkability of a wool treated by the method of this invention.

The dimensional stability or I.W.S. test is carried out on a piece of worsted wool having a well-defined length which is introduced into Ia sheath of unshrinkable cotton. Then the sample is washed and the piece of worsted wool is measured after washing. The results shown in Table I hereinafter correspond to a 30-second exposure of the wool samples to the action of sparks at a temperature combs 6 following the contour (in plan view) of the 45 of about 40.

TABLE I Sample I Sample II Sample III Quality 64s Quality 62l Quality 66s 1/2 ch 2/32 Twist 430 2/28 Twist 410 Lyster 2/28 Twist 410 Untreated Treated Untreated Treated Untreated Treated wool wool wool Wool wool wool Tensile test on single yarn (l) (2) (l) (3) 0) (2) Strength in grams 196. 5 258 202 219. 6 248. 5 296. 4 Elongation, percent 9. 12 11. 46 10 11. 6 15. 4 18.2 Dimensional variations, percent:

Worsted 18. 1 5. 7 12. 45 6. 1 14. 5 10. 7 Yarns 15. 5 1 18. 4 7. 1 17. 5 9. 8 Knittted fabric tests (Shriukage, percen I.W.S. Test (l/ hr.) 13 5. 2 14. 3 5. 15 19 6. 5

Sample IV Sample V Sample VI Quality Cap wool Quality 64n Quality 56- 1/14 1/28 Twist 410 1/28 Twist 410 Twist 290 1/2 chain.

Untreated Treated Untreated Treated Untreated Treated wo wool wool wool wool wool Tensile test on single yarn- (l) (4) (l) (5) (5) (2) Strength in grams 203. 8 255. 8 212. 4 288. 8 561. 5 635. 5 Elongation, ercent 9.7 18. 8 11 17. 8 16. 58 18. 13 Dimensione variations, percen l Worsted 18. 2 9. 5 17. 8 14. 6 14. 4 2.85 Yarns 23. 1 10. 55 16. 6 9. 3 10. 4 2. 6 Knitted fabric tests (shrinkage, percent I.W.S.)Test (l/ hr.) 38. 0 4.9 28. 9 4. 4 10.4 2. 75

l Not possible.

2 Withstands 5,000 tractions. 8 Withstands 4,000 traetions. 4 Withstands 4,500 tractions. Withstands 2,000 tractions.

The following Table II shows the inliuence of the treatment time in the case of a worsted wool sample submitted to the action of sparks respectively during 23-second and 46-second time periods. i

TABLE II [Quality 64I-Fatty eontent=0.432/28 sampling-410 x 205. Prepared, spun, twisted, S.E.knitted, C.F.0. 41]

Wool Wool Untreated treated treated wool during during 23 sec. 46 sec.

Tensile test on single yarn (number of tractions) I 1, 500 5,000 5, 000 Strength in grams 276 288 309. 6 Elongation, percent 13.1 15.1 18. 4 Dimensional variation, percent: Wor- 1 5 ed 13. 6 5 2. 8 Knitted fabric test (30 x 40): .W.S.

Test (y, hr.) 26. 4 6. 2 4. 5

The results of comparative tests carried out with a view to ascertain the alteration of the textile fibres, respectively in the case of a non-treated wool, in the case of a wool treated according to the method of this invention, and in the case of -a wool treated by a conventional chlorine process (or by any other process utilizing a chem- 25 ical likely to degrade the textile material), are shown in the following Table III concerning an alkaline solubility test characterizing the loss of weight of textile fibres (percent), after the attack by the alkaline medium. This test evidences the state of alteration of the fibers.

TABLE IIL-ALKALINE SOLUBILITY TEST Loss of weight (percent) after the attack of the fibres by the alkaline medium:

Untreated wool 12.41 Wool treated by the method of this invention 13.06 Wool treated by the chemical process 19.65

What I claim is:

1. Method of treating textile materials of animal origin which comprises the steps of applying between two electrodes a potential greater than that necessary to produce a disruptive discharge at a high frequency and a low intensity current so as to produce, in the free atmosphere, a shower of sparks creating between said electrodes a temperature low enough to avoid any deterioration of the treated textile fibres, and causing the textile material to pass through said spark shower.

2. The method of claim 1 wherein the temperature is maintained below 100 C.

3. The method of claim 1 wherein the temperature is maintained below C.

4. The method of claim 1 wherein the textile material is treated for a period less than seconds.

5. The method of claim 1 wherein the textile material is wool.

References Cited UNITED STATES PATENTS 2,977,475 3/1961 Kassenbeck Z50-49.5

ROBERT K. MIHALEK, Primary Examiner.

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