DE1963588A1 - Process for removing the melt and for desizing textiles containing synthetic fibers - Google Patents

Description

" Process for removing the sludge and for desizing textiles containing synthetic fibers"

The invention relates to a method by means of which the products of the sizing and sizing can be produced at the same time can remove from fabrics.

Textile fibers or threads, especially those of so-called artificial textiles (viscose, cellulose diacetate and triacetate) or real synthetic fibers or threads (polyamides, polyesters, synthetic fibers made of polyacrylic, polyvinyl or polypropylene base, etc.) are common protected and made slippery by a coating, which usually consists of an aqueous emulsion or a solvent dissolved fat. Such a coating represents the "Schmälze". Shall the threads

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serve as a chain in fabrics, they must also receive a further protective coating, the size. the Sizing is different depending on the type of thread; with plastic threads it usually consists of polyacrylic acid or the corresponding polymers.

Both the sizing and the sizing must be removed before dyeing. Is it decolorization? of threads, regardless of the way in which this is carried out, generally only the gap has to be removed four den. It is the same when dyeing jerseys in one piece. The case is different with tissues where at the same time the sintering must be removed from the weft and from the warp and the sizing from the latter. '

When removing the sludge one usually works with aqueous baths, the emulsifiers or detergents or both included together.

For desizing, products are used which are adapted to the nature of the sizing. In the case of polyacrylic acid, these products are bases or alkaline salts which are capable of saponifying the acid with the formation of water-soluble salts. In this case, the salts formed can be present in addition to the smocks for removing the smear. In order to achieve an effect in a short time, the treatment must be carried out in the heat, ζ v / i see 60 and 30 C, be carried out. In the case of tricot fabrics or fabrics which contain synthetic fibers or threads, the treatment must also be carried out in the heat before fixing, as otherwise the heat treatment would make it impossible to remove the sizing and sizing. This results in the need for the tissue to be

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Deslightening and desizing to dry. Even if the Heat setting carried out after dyeing or printing is, a drying step is still necessary in most cases, which requires a significant amount of heat Conditional, because the textiles contain at least 50% water after they have been squeezed. There are also Costs for the driving force, for the necessary manual labor and also the amortization costs for the complex and bulky drying and conveyor systems.

Finally, it should also be taken into account that the removal of the narrowing and, in particular, the desizing of what this is generally followed by rinsing with running water, Consume and pollute a very significant volume of water.

A method has now been found that is convenient and quick to carry out, with which one can at the same time use the for peeling products used based on fatty substances and those used for sizing based on polyacrylic acid can remove.

The method according to the invention is carried out in a manner known per se and in known devices in an anhydrous manner Medium with the aid of an organic solvent or a mixture of such solvents, in which im dissolved state contains an organic or inorganic alkaline agent, a dissolution of the mentioned Coating materials.

The organic solvent can be non-polar and is e.g. a halogenated carbon, such as perchlorethylene (Tetrachlorethylene) or it can be polar, such as

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a phenol or an alcohol, e.g. isopropanol.

If there is a mixture, it can consist of several polar or several non-polar or simultaneously of polar and non-polar solvents. An azeotrope that is formed from a non-polar halogenated solvents and a polar solvent with one or more alcohol functions. The advantage of one Such a mixture is that on the one hand it has a better dissolving power compared to certain fatty bodies that are in the Liquids can be contained, and that it is on the other hand less flammable than a polar alcoholic Solvent. In addition, such a solvent mixture can easily be recovered by distillation leaves. As an example of such an azeotrope, the one cited, which is the isopropanol with the tetrachlorethylene forms.

As an alkaline agent one can either use an organic basic one Use a salt or an organic base, such as pyridine, piperidine and their analogues, or even one inorganic base or a basic salt, such as potassium hydroxide, or a mixture of inorganic and / or organic bases or salts.

In order to remove the dissolved substances from the treated material, a subsequent rinse is essential; it can with help of a solvent and expediently with the aid of one of the constituents of the for the removal of the size and the sludge the bath used. If the bath consists of the azeotrope of isopropanol and tetrachlorethylene, then used it is advantageous to use tetrachlorethylene for rinsing.

The inventive method has a number of advantages

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1. Due. the high dissolving power of the solvent can be seen work at ambient temperature and with a short treatment time.

2. The subsequent drying is largely restricted or completely suppressed, provided that solvents are used or solvent mixtures that boil as low as possible and at least have the boiling point below that of water. If their vapor tension is sufficiently high at ambient temperature, then

. It may be sufficient to blow air through to drive off the solvents, so that the drying process is superfluous and the textile materials can be brought directly into the dyebath, provided that the dyebath itself is only organic solvents and if the thermal! fixation is carried out on the colored cloth. Of course must be the solvents contained in the desizing and desizing bath on the one hand and in the dyebath on the other hand be compatible with each other.

If the thermal fixation takes place before the coloring, no drying is necessary before the fixation either, provided that the fixation device has facilities to collect the reusable organic Has solvent.

3. The consumption and pollution of water are the same Zero.

4. The solvents can be regenerated by distillation or other methods and used again in the next operation be used. Their consumption is therefore limited to the losses in recovery, which can easily be achieved hold at a maximum of about 5%.

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5 «To that by treatment at normal temperature and The saving of heat units achieved by the elimination of drying is still a significant saving Manual work due to the rapid treatment process.

The system of solvents (pure or mixed) and alkaline agents can be applied to the textile to be treated in the usual way, namely as follows:

by pressing or sucking the liquid through the solid textiles, as is generally the case is in the case of spider cakes, wraps or strands by wrapping or in the case of / perforated weaver trees rolled up fabrics or Knitted;

or by placing the textiles in the resting liquid, as is generally the case with woven or knitted fabrics that are placed on dye reels, jiggers, in flow runners, treated on foulards etc.

The method according to the invention can be carried out with the usual devices, provided, of course, that the Metals and compounds are resistant to the solvents and that with regard to the solvent vapors Appropriate measures are taken, on the one hand, their extraction for the purpose of cleaning by distillation allow and on the other hand ensure the safety of the operating personnel and healthy working conditions »

In carrying out the method in practice, it is particularly important that the result be controlled in a simple manner can be, whereby the control at the workplace must be feasible even by untrained personnel and not only in the laboratory, which is always possible, but takes a long time and, if necessary, an immediate correction

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makes impossible.

For this purpose, a control method was worked out in which the property of polyacrylic acid was used that it becomes insoluble under the influence of dry heat and that it reacts with the reactant known under the trade name "Identex II" (manufacturer "Societe Francaise des Iiatieres Colorantes") ) immediately turns green. The critical temperature from which the polyacrylic acid gives this green color to a non-desized fabric is 170 ^° C. However, the polymer is made insoluble under the influence of the heat necessary for the thermal fixation of the fibers. It must therefore be determined whether there are still residues of polyacrylic acid after the removal of glue which have become insoluble as a result of the fixing treatment. From this point of view, it has been found that a valuable measure of the degree of desizing can be obtained if a series of blocks are applied to the fabric to be examined, at temperatures increasing from block to block between 171 ° C. and the limit temperature at which the fixing is performed are heated.

Is, for example, the examined tissue of threads of Polyanid 6-6, which is thormofixiert at 210 ⁰ C and is DIE series of 4- stepwise to 171-213 ° C, for example at 176 ° - "OE5 ° - 193 ° - 204 ⁰ C heated blocks, one can to evaluate the block of 171 °, the number 1, that of 176 ⁰ the Ituiiner 2, the 183 number 3, that of 193 ° the number ''', that of 204 ° the Kuruner 5 and give the number 6 to that of 213 °; the respective degree of desizing is then graded from 1 to 6, depending on whether the surface in contact with the block in question turns green when the reaction agent "Identex II" has been used

bath

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occurs, whereby of course the contact time and the contact pressure must be kept the same.

A convenient means of performing this test is a thermotest-type blocked device (Constructor "AHAM"), who used to determine the resistance of dyeings on synthetic fibers to sublimation is determined and has calibrations on a scale with the following temperature values in ° C: 149 ° - 154 ° - 158 ° - 161 ° - 165 ° - 171 ° - 176 ° - 183 ° - 193 ° - 204 ° - 213 ° - 225 ° 229 °. Incidentally, the device has five scales each 13 "Temperature values, which correspond to the degree of heating of the Blocks correspond, namely:

Degree of heating A: 119-177 G Il B: 129 ° - 194 ° C Il C: 139 ° - 212 ⁰ C Il D: 149 ° - 229 ° C Il E: 159 ° - 246 ⁰ C

So you can choose one of the scales (e.g. the D scale for the above example) and stick to it, depending on the usual way to test synthetic fibers.

When carrying out the tests with this device, it is sufficient if one of the desized fabric is used Remove strips of 6 χ 40 cm and put them in the Bringing contact with the row of heated blocks, counting the blocks between 171 and 229 ° C the strip is then immersed in an aqueous solution (1 g / l) of the reactant "Identex" at 15 °, the strip is soaped, then quickly soak it in the heat, rinse it off well and determine from which block the green color appears.

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Of course, the "Thermotest ADAM" can pass. any other device can be replaced, which a contact of a certain duration under a specified Allows printing with surfaces heated to precisely set temperatures; the device described is only mentioned as an example and because it is used where fabric made of synthetic threads is treated, is available anyway.

The examples illustrate the inventive method for Removing the sizing and desizing and checking the results more closely.

example - Λ

The test is performed on a taffeta made of polyamide 6-6 of 96 g / m, the chain of which carries a sizing of polyacrylic acid of 1 to 2% of the chain weight and wherein the excess based a Schmälze of emulsified mineral oil of 1 ¹ / j oil, on the weight of the total fabric, on v / eist. The unbleached, dry fabric is passed at a speed of 100 m / min over a padder with two rollers, which causes a squeeze rate of 65%, through a bath of 18, which has the following composition (content per 100 l):

70 l isopropanol
30 1 tetrachlorethylene
3OO g solid potassium hydroxide.

The rolled after leaving the foulard tissue is stored in roll form? Λ hr. At ambient temperature. It is then transported at a speed of 15 m / min in a vat with small rollers, which has a passage length of 5 m.

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v / eist, rinsed in tetrachlorethylene held ^{at 80 0 C.} When leaving the vat, 80 % of the liquid is squeezed off. The fabric then runs over a short conveyor track, which consists of an evaporation canister kept at the temperature necessary for evaporation of the solvent with a collecting device for the solvent vapor and a chamber kept at 2 ^ 0 C for thermofi :: ation: the run time over the conveyor track is not More than 2 minutes read the fabric rolled up again at the end of the conveyor track is intended for dyeing.

The degree of desizing is determined on a strip which is removed from the web after storage for 24 hours. The strip is briefly rinsed in a beaker in tetrachlorethylene held at 8G G, dried, "<min kept in contact with the heated blocks of the thermal test device described above and finally i min at ^^> ° C in the reagent" Ideritex II "immersed, after which it is matured and rinsed.

The result is an evaluation of the degree of arbitration of 6, i.e. the desizing is excellent.

Example 2

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A piece of sized .folyainid-6 fabric of SO g / m is used inserted as a wrap in a closed jigger, in filled with a solution of "0> w piperidine in trichlorethylene became.

You leave the piece only once at ambient temperature Go through bath. The VJiekel is removed from the jigger and Stored at ambient temperature for 24 hours, taking in slower Rotation is held.

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The lap then runs into a second closed jigger, which contains an ethylene trichloride bath kept at 8ü ° C. There is only one single pass at maximum speed. A squeezing device is arranged behind the jigger, which has a short evaporation chamber with a collecting device for the solvent fights and a device for rolling up the fabric, which is now to be printed and subsequent thermal fixing is ready.

In this case, the check carried out according to example 1 is limited to degree of de-isolating 3, since the The maximum temperature for polyamide 6 is 180 ° C.

PATEKTAKSHiÜCHE

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Claims (7)

Dit.äro.r.wuxsTnoFP. β mühohsn bo 1963588 DXPJU Uta. O. PULS scavmaERSTRAssx « DKJLt.PXOHMANM τβ »» · ι «i ··» DR. ING. D. BKIIRBNS τ «ι« · »4» ιιΐ * βΐΒ ·· «ι nonnpiTUT μΟκοιιι 1A-37 108 PATENT CLAIMS s M) / method for removing the sintering and for desizing by a coating of fatty substances and polymers Textile fibers or threads protected by acrylic acid or its derivatives, marked thereby that one with the help of an organic solvent or a mixture of such solvents, wherein an organic or inorganic alkaline agent is contained in the dissolved state, a dissolution of the sludge and the size effected in an anhydrous medium. 2) Method according to claim 1, characterized in that _t nan a polar or non-polar organic solvent or a mixture of one or more polar, and uses one or more non-polar solvents " 3} Process according to claim 2, characterized in that the solvent used is trichlorethylene used. 4) Method according to claim 2, characterized in that one uses _t the azeotrope of isopropanol and tetrachlorethylene as the solvent. 5) Method according to one of claims 1 to 4-, characterized characterized that the alkaline additive 009826/2021 - 2 - 196J588 1A-37 108 -> ^Γ - 13 substitute one or more basic salts or organic and / or inorganic bases are used. 6) Method according to claim 5 »characterized in that one is used as an alkaline additive solid potassium hydroxide or piperidine is used. 7) Method according to one of claims 1 "to 6, characterized characterized in that the dissolution of the sludge and the size at ambient temperature within a very short time causes the textile goods to be stored and then in the warm organic solvent or solvent geraisch is rinsed, after which one or the solvent at the end with recovery the vapors evaporate. 009826/2021