EP0492649B1 - Method of modifying the properties of a textile substrate - Google Patents

Abstract

A process is described for the production of a sewing thread, particularly a sewing thread containing synthetic fibres, provided with a finishing agent. In this process, after spinning, a finishing agent is applied to the sewing thread, with the application to the sewing thread of monomers and/or oligomers which undergo ionic and/or radical oligomerisation or polymerisation to develop the finishing agent, and/of the finishing agent itself, and a treatment to produce radicals and/or ions is performed before the application of the monomers, oligomers and/or the finishing agent, simultaneously with the application and/or after the application of the monomers, oligomers and/or the finishing agent.

Description

The present invention relates to a method for changing the properties of a textile substrate with the features of the preamble of patent claim 1.

There are several possibilities for changing the properties of a textile substrate, for example a fiber, a sewing thread, a flat structure, a composite material or the like. If the textile substrate is a synthetic polymer, the desired change can already be brought about in the manufacture of the polymer by chemical modification of the building blocks forming the polymer. The fibers produced in this way are then referred to as modified fibers.

Physical or chemical treatments in the course of finishing textile substrates can also change their properties. For example, chlorination of wool substrates can reduce the tendency to felt and the shrinking behavior of woolen fabrics. In the case of cotton articles, the final properties, such as the ironing or Washing behavior, can be improved by applying suitable equipment to the cotton articles. In the case of synthetic yarns or synthetic fabrics, the shrinking properties of these substrates can be changed considerably by thermal treatments.

DE 25 38 092 A1 describes a method for changing the properties of a textile substrate, a sensitizer based on a carbonyl-containing compound being applied to the substrate to be treated in the known method. This is followed by UV irradiation, the sensitizer applied beforehand causing the effect of UV irradiation to be increased in such a way that the irradiation time is at most a few minutes.

A method for treating a textile material in an ionizing gas atmosphere can be found in FR 15 10 883 A1 in order to improve the adhesion of the textile material to rubber. As can easily be seen from the only figure in FR 15 10 883 A1, the textile material is treated in a single-layer arrangement.

A method with the features of the preamble of claim 1 is known from DE 20 25 454 A1. This known method, which however always requires keratin-containing fiber substrates, provides for an upstream reduction and a subsequent oxidation of the fiber substrate, the oxidizing solution used for this containing an initiator which obviously only releases free radicals in the presence of mercaptan.

However, the known processes described above have the disadvantage that they are very difficult to carry out on the one hand and on the other hand only cause a gradual change in the properties of the textile substrates treated in this way.

The present invention has for its object to provide a method of the type specified, with which the properties of textile substrates can be changed in a particularly simple manner in a variety of ways.

According to the invention, this object is achieved by a method having the characterizing features of patent claim 1.

The method according to the invention for changing the properties of a textile substrate provides that an initiator is applied to the textile substrate, which decomposes into radicals and / or ions through a physical treatment. In this case, in the process according to the invention, a heap or a winding body is first produced from the textile substrate, a gaseous initiator or a solution, dispersion or emulsion of the initiator flows through the heap or the winding body and the treatment is carried out simultaneously and / or subsequently , wherein the radicals and / or ions formed in this way react with the textile substrate itself, a substance applied thereon and / or with a gas surrounding the textile substrate.

The inventive method described above has a number of advantages. First of all, it should be noted that the method according to the invention enables a chemical and / or physical change of the textile substrate treated according to the method according to the invention in a particularly simple manner. This is related to the fact that in the simplest case only the initiator is applied to the textile substrate made up as a winding body or pile and afterwards the physical treatment which is used to generate radicals and / or ions from the initiator has to be carried out in order to do so cause the textile substrate to react with itself or with at least one gas surrounding the textile substrate. This reaction then has the result that, for example, crosslinking reactions of the fiber polymers forming the textile substrate take place at the points at which the initiator is applied to the textile substrate. This then results in chemically crosslinked fiber polymers, which naturally have their properties, for example their strength, their hydrophilicity, their hydrophobicity or their Wettability with water are completely different from the corresponding properties of the starting polymers. If a gas, for example a reactive gas, is still present in such a process, reactive groups form on and / or in the fiber polymer at the points at which the initiator decomposes due to the physical treatment, which groups are then used for further reactions, For example, the chemical bonding of equipment or a dye can be used.

If, in the method according to the invention, the physical treatment of the textile substrate is carried out in such a way that a substance, for example an oligomerizable or polymerizable substance, is previously applied to the textile substrate, the method according to the invention has the effect that this substance due to the formation of radicals and / or Ions themselves oligomerize or polymerize and / or that this substance is chemically and / or physically bound to the fiber polymer.

A suitable embodiment of the method according to the invention provides that the method according to the invention is carried out in the presence of a gas. Here, the selection of the gas in the process according to the invention depends on which effects are to be achieved by the process according to the invention. Is it For example, if the process according to the invention is intended to crosslink the fiber polymers, for example the filaments of a yarn, which form the textile substrate, the physical treatment by which the free radicals and / or ions form, preferably in, is carried out an inert gas or an inert gas mixture, for example from an inert gas and / or nitrogen. The use of the inert gas then generally prevents reactive groups from forming on the fiber polymer. On the other hand, if the process according to the invention is intended to generate reactive groups in the areas of the fiber polymer in which the initiator was previously applied, reactive gases are preferably used for this, such as in particular O ₂ , N ₂ O, O ₃ , CO ₂ , NH ₃ , SO ₂ , SiCl ₄ , CCl ₄ , CF ₃ Cl, CF ₄ , SF ₆ , CO and / or H ₂ . Here, these gases, which are used as individual gases or gas mixtures, either react directly with the formation of the corresponding functional groups with the radicals or ions generated in the physical treatment by the decomposition of the initiator, or the gas chemically bonded to the fiber polymer can then by a suitable aftertreatment, for example with water, acids or alkalis, can be converted into the corresponding reactive (functional) groups.

The number of crosslinking points or of the reactive groups generated by the method according to the invention can be varied by the amount of initiator applied.

Furthermore, in the embodiments of the method according to the invention which lead to reactive groups on the fiber polymer, there is the possibility of controlling the amount of functional (reactive) groups by varying the concentration of the aforementioned reactive gases during the physical treatment. In the simplest case, this is achieved by diluting the aforementioned reactive gases with a suitable inert gas, for example a noble gas, a noble gas mixture and / or nitrogen.

The above-described formation of the functional groups of the fiber polymers forming the textile substrate then has the effect that, depending on the nature of the respective functional group, a material treated in this way, in particular a polyester material, can be dyed or printed particularly easily with cationic or anionic dyes or reactive dyes. For example, it was found that the introduction of functional groups of this type, which made it difficult and difficult to dye aramid fibers or polyalkylene fibers, in particular polypropylene fibers, could be easily and easily dyed with ionic dyes or reactive dyes after appropriate treatment. It was also found that Equipment that has corresponding corresponding functional groups could be chemically (covalently or ionically bonded) bound to the functional groups of the fiber polymer previously produced by using the method according to the invention. This then means that such equipment is permanently and permanently fixed to the respective textile substrate, so that even during later use, this equipment permanently gives the desired substrate property changes. In the case of sewing threads, it was found that a sewing thread equipped in this way, in which the equipment was chemically bound to the fiber polymer, compared to a sewing thread in which the same equipment was not chemically bound to the fiber polymer, had a much better sewing behavior.

Another embodiment variant of the method according to the invention for producing a finish on the textile substrate provides that the physical treatment for destroying the initiator is carried out in the presence of a substance. This in turn means that either the substance is bound to the fiber polymer via the radicals and / or ions formed in the process according to the invention, the substance is oligomerized or polymerized with itself without binding to the fiber polymer, or that the substance both to the Fiber polymer is bound as well as oligomerized or polymerized with itself. In the process according to the invention, a substance is preferably selected which is free-radically and / or ionically oligomerizable or free-radically and / or ionically polymerizable.

In the process according to the invention, the selection of the oligomerizable or polymerizable substances used in each case depends on the changes in properties desired in each case.

A first embodiment of the process according to the invention thus provides that a substance is used which comprises oligomerizable or polymerizable hydrocarbons or hydrocarbon derivatives. These include, for example, alkylenes, in particular ethylene, propylene, isobutylene, butadiene, isoprine, methylstyrene, xylylene and halogen derivatives of the abovementioned compounds, in particular vinyl chloride, vinylidene chloride, tetrafluorethylene, trifluorethylene, vinyl fluoride, vinylidene fluoride, pentafluorostyrene, 2,2,3,3-tetrafluoropropyl methacrylate , and / or mixtures of the aforementioned compounds and in particular mixtures of tetrafluoroethylene / perfluoropropylene, tetrafluoroethylene / perfluoroalkyl vinyl ether, tetrafluoroethylene / ethylene, trifluorochloroethylene / ethylene and hexafluoroisobutylene / vinylidene fluoride.

In addition to or instead of the aforementioned substances, depending on the desired changes in properties, those substances can also be selected in the process according to the invention which comprise oligomerizable or polymerizable acrylic acid, acrylic acid derivatives and / or salts of these compounds. In particular, methacrylates, ethyl acrylates, n-butyl acrylates, isobutyl acrylates, tert-butyl acrylates, hexyl acrylates, 2-ethylhexyl acrylates and lauryl acrylates are to be mentioned here. Furthermore, these acrylates can be mixed with suitable compounds, such as, for example, methyl methacrylates, ethylene methacrylates, n-butyl methacrylates, acrylonitrile, styrene, 1,3-butadiene, vinyl acetate, vinyl propoinate, vinyl chloride, vinylidene chloride, vinyl fluoride and / or vinylidene fluoride. Also suitable as acrylic acid derivatives are acrylic acid, methacrylic acid, acrylamide, acrylonitrile, methacrylamide and / or salts of the aforementioned two acids.

If, in the method according to the invention, a three-dimensional crosslinking of the substance applied to the textile substrate is additionally desired, then those products which have additional free functional groups are added to the aforementioned oligomerizable or polymerizable substances. Particularly suitable for this purpose are carboxyl-containing monomers, such as in particular maleic acid and / or itaconic acid; monomers containing hydroxyl groups, such as, in particular, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, propylene glycol methacrylate and / or butanediol monoacrylate; N-hydroxymethyl group-containing monomers, such as, in particular, N-hydroxymethylacrylamide and / or N-hydroxymethylmethacrylamide; and / or sulfonic acid-containing monomers, in particular 2-acrylamino-2-methylpropanesulfonic acid. Corresponding ethers, in particular ethyl diglycol acrylate; Amines, especially tert-butylaminomethacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate and / or diethylaminoethyl acrylate; Epoxies, especially glycidyl methacrylate; and / or monomers containing halogen hydroxyl groups, in particular 3-chloro-2-hydroxypropyl acrylate. However, it is of course also possible to use the aforementioned functional group-containing products alone.

Furthermore, in the process according to the invention, in addition to the substances mentioned above or instead of the substances mentioned above, products which include styrene and / or styrene derivatives are also suitable. In addition to the styrene or methylstyrene already mentioned, the mixtures of styrene and / or methylstyrene with acrylonitrile and / or of styrene and / or methylstyrene with butadiene should be mentioned in particular.

In the process according to the invention, it is also possible to select substances which have organosilicon compounds. These are then preferably silicones which correspondingly have one or more organic radicals on the silicon atom which can be radically and / or ionically oplygomerized or polymerized. Organic residues which have terminal C-C double bonds are particularly suitable for this purpose.

The application quantity of the aforementioned substances varies depending on the desired changes in the properties. In the method according to the invention, the application amount of the aforementioned substances is usually between about 0.01% by weight and about 20% by weight, in particular between 0.5% by weight and 10% by weight (mass of the oligomerizable or polymerizable substance: mass of the textile substrate).

If the method according to the invention is intended to change the properties of a sewing thread which is said to have improved abrasion resistance compared to mechanical stress, the layer thickness, in addition to the selection of the selected substance, has a decisive influence on the resistance of the sewing thread to mechanical stress during processing. In particular, the The amount applied varies so that the finished sewing thread has a liquid or solid, almost completely or completely continuous substance layer on its surface, the thickness of which varies between approximately 100 nm and 0.1 nm, in particular between 20 nm and 2 nm.

With regard to the selection of the initiator used in the process according to the invention, it should generally be stated that only those initiators are selected here which actually decompose into radicals and / or ions under the respectively selected conditions of the physical treatment. Furthermore, an important selection criterion for the initiator is that the decomposition of the initiator brought about by the physical treatment takes place under conditions in which the fiber polymers forming the textile substrate remain unchanged, so that the desired changes in properties are not caused by the physical treatment as such but exclusively can be brought about by the decomposition of the initiator and the subsequent reactions that follow. In the context of this application, the term initiator also includes mixtures which contain several initiators.

Preferred initiators which are used alone or in a mixture in the process according to the invention are Initiators based on a persulfate, preferably potassium persulfate or ammonium persulfate; Initiators based on a peroxide, in particular dibenzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, di-tert-butyl peroxide, cyclohexylsulfonylacetyl peroxide; Initiators based on an azo compound, in particular azodiisobutyronitrile, and / or 4,4'-azo-bis- (4-cyanopentanoic acid chloride). Initiators based on benzpinacol, diisopropyl percarbonate and / or butyl peroctoate can also be used.

It is particularly suitable in the process according to the invention if redox systems are used here as initiators. In physical treatment, these redox systems deliver a particularly high yield of the radicals or ions generated thereby. In particular, potassium persulfate and / or ammonium persulfate / sodium hyposulfite; Hydrogen peroxide / iron (II) sulfate; Cumene hydroperoxide / polyamine and / or benzoyl peroxide / N-dimethylaniline used.

A further embodiment of the method according to the invention provides that the textile substrate is swollen before and / or when the initiator is applied by adding a swelling agent. Such material-specific and the person skilled in the art for the particular substrate in particular Swelling agents known from the dyeing processes, such as, for example, alkali for cellulose-containing substrates or aromatic hydrocarbons for substrates containing polyester or polyamide, have the effect that the initiator is not only adsorbed or absorbed on the surface of the substrate, but also in particular in the amorphous regions of the substrate can diffuse in, so that the corresponding radical and / or ion formation also takes place inside the fiber.

There are two ways of carrying out the previously described adsorption or absorption of the initiator on the respective textile substrate. In the case of initiators of this type which can be converted into the gas state without being destroyed, the initiator can be applied to the textile substrate by flowing or flowing through the textile substrate in the form of a pile or winding body with the gaseous initiator for a predetermined time. It is advisable here for the gaseous initiator to flow through the textile substrate for a predetermined time, in particular between two minutes and thirty minutes.

If, on the other hand, the selected initiator cannot be converted into the gaseous state without decomposition, a corresponding solution, dispersion or emulsion, preferably in water or in a solvent, in particular in a low-boiling solvent, manufactured. Subsequently, this solution, dispersion or emulsion flows through the winding body or the pile value, the above-mentioned predetermined time being preferred.

Depending on the initiator used, the physical treatment required in the process according to the invention for destroying the initiator can be thermal treatment, irradiation with light, in particular with UV light, α, β, or γ irradiation or treatment in an electrical field.

A particularly suitable embodiment of the method according to the invention provides that the physical treatment is a low-temperature plasma treatment. In general, the conditions of the low-temperature plasma treatment, e.g. the pressure, the power, the frequency, the residence time, the power density and the gas or substance used, depending on the initiator selected, the material of the textile substrate to be treated and the desired changes in properties.

In the method according to the invention, the low-temperature plasma treatment is usually carried out under a vacuum between 5 Pa and 500 Pa. Particularly good results with regard to the yield are obtained if the low-temperature plasma treatment is carried out under a vacuum between 20 Pa and 300 Pa, preferably between 70 Pa and 200 Pa.

Another embodiment of the method described above provides that in the low-temperature plasma treatment, a vacuum between 5 Pa and 120 Pa, preferably between about 20 Pa and 120 Pa, during a first treatment period and a vacuum between during a subsequent second treatment period 80 Pa and 250 Pa, preferably between 100 Pa and 200 Pa. As a result, in particular, a reactive gas or an inert gas flows through the winding body or the pile particularly well and uniformly, which consequently particularly ensures the uniformity of the generation of the radicals or ions. Especially in cases in which a first treatment period immediately follows a second treatment period, and above all when the first and second treatment periods are repeated several times in quick succession, the winding body or the pile is particularly well flowed through, so that Irregularities across the thickness of the winding body or the pile are completely excluded.

In the procedure described above, in which two successive treatment periods are carried out with a different vacuum, the transition from the first treatment period to the second treatment period and from the second treatment period to the first treatment period can be designed in such a way that the vacuum is suddenly set in each treatment period. A particularly gentle treatment of the winding body or the pile, however, enables an embodiment of the method according to the invention, in which the vacuum in the first treatment period is continuously transferred to the vacuum in the second treatment period and the vacuum in the second treatment period is continuously transferred to the vacuum in the first treatment period, so that the pressure is increased or decreased sinusoidally throughout the treatment.

Regarding the residence time in the low-temperature plasma treatment, it should be noted that this varies between 10 seconds and 160 seconds, preferably between 20 seconds and 60 seconds, in each treatment period.

To undesired and uncontrolled side effects, caused by foreign gases, in the low-temperature plasma treatment To prevent it, it is advisable to set a vacuum at a pressure which is lower than the pressure during the low-temperature plasma treatment at the beginning of the low-temperature plasma treatment. If desired, a corresponding gas (reactive gas and / or inert gas) is then fed in until the desired pressure for the low-temperature plasma treatment is reached.

The frequency in the low-temperature plasma treatment is usually between 1 MHz and 20 MHz, the low-temperature plasma treatment preferably being carried out at a frequency of 13.56 MHz.

In addition, in the method according to the invention, the low-temperature plasma treatment, which leads to the destruction of the initiator and thus to the formation of the radicals and / or ions, can also be carried out at a frequency of 27.12, 40.68 and / or 81.36 MHz , but it is also possible to change the frequencies in the aforementioned range during the low-temperature plasma treatment or to set them to different values within the scope of the aforementioned values.

The power used in low temperature plasma treatment varies between 200 watts and 600 watts.

The power density in the low-temperature plasma treatment varies between 2 W / dm ³ and 25 W / dm ³ , the volume information relating to the volume of the autoclave used in each case. However, in the method according to the invention, work is preferably carried out at a power density between 8 W / dm ³ and 14 W / dm ³ , in particular at 12.5 W / dm ³ .

Particularly good results are also achieved in the method according to the invention with a low-temperature plasma treatment which is carried out at a frequency of 2.45 GHz, at a pressure between 10 ^-1 Pa and 1,000 Pa, preferably between 70 Pa and 120 Pa, and at a power density between 0.1 W / dm ³ and 5 W / dm ³ , preferably between 1.5 W / dm ³ and 3 W / dm ³ .

Another, likewise preferred embodiment of the method according to the invention provides that a corona treatment is selected as the physical treatment which leads to the destruction of the initiator and to the formation of the radicals and / or ions.

This corona treatment is preferably carried out at a pressure which is at normal pressure and / or slightly above and / or slightly below normal pressure. Thus, in the method according to the invention, the corona treatment is carried out at a pressure between 86.659 x 10 ³ Pa and 133.32 x 10 ³ Pa, preferably at a pressure between 93.325 x 10 ³ Pa and 113.324 x 10 ³ Pa.

Particularly good results with regard to the disintegration of the initiator can be achieved if the pressure in the corona treatment is between 86.659 x 10 ³ Pa and 99.99 x 10 ³ Pa during a first treatment period and between 99 during a second treatment period , 99 x 10 ³ Pa and 133.32 x 10 ³ Pa. This is obviously due to the fact that the pressure change flows through the winding body or the pile particularly well and uniformly. Consequently, this results in a uniform distribution of the systems reacted, so that the property changes brought about by the process according to the invention are also particularly uniform. In particular, in the embodiment described above, the first treatment period immediately follows the second treatment period, it being advisable to repeat this treatment cycle, consisting of the first and second treatment periods, several times alternately.

As has already been described in the case of the low-temperature plasma treatment, the pressure change between the first and second treatment periods can also be carried out abruptly in the case of the corona treatment. Here, however, there is a risk that the winding body or the pile accumulates in an undesirable manner during the abrupt pressure change, so that especially in the case of relatively soft winding bodies or soft packed piles, i.e. those packages or heaps in which the Shore hardness is low, a continuous pressure increase is carried out during the transition from the first treatment period to the second treatment period and a continuous pressure reduction is carried out during the transition from the second treatment period to the first treatment period. This pressure change is then preferably carried out sinusoidally, with treatment times between 10 seconds and 160 seconds, in particular between 20 seconds and 60 seconds, being selected for the first and second periods.

In order to eliminate undesirable external influences during the corona treatment, such as water vapor or dust particles originating from the air humidity or the textile substrate, which can lead to an uncontrolled, non-reproducible corona discharge and thus to an uncontrolled destruction of the initiator, it is recommended before starting corona treatment, set a pressure less than the pressure during the corona treatment. A defined amount of a gas (reactive gas and / or inert gas) is then fed in to set the required treatment pressure. In this case, the autoclave used for the corona treatment is preferably evacuated to a pressure between 1,000 Pa and 10,000 Pa so that the respective gas and possibly the liquid enriched with substance that flows through the winding body or the pile are then supplied can be set so as to set the pressure in the autoclave between 86.659 x 10 ³ Pa and 133.32 x 10 ³ Pa.

The gases used in the low-temperature plasma treatment or corona treatment have already been described in detail above.

The total treatment time for the low-temperature plasma treatment or corona treatment is between about two minutes and about thirty minutes, preferably between about five minutes and about twenty minutes, depending on the desired changes in properties, the power densities set, the initiators selected and the particular textile substrate.

As already mentioned above, the method according to the invention achieves particularly good results if the textile substrate is opened up as a pile or as a winding body and excluding a low-temperature plasma treatment, since it is not necessary to wrap the textile substrate to be treated within the vacuum chamber required for the low-temperature plasma treatment, so that the otherwise necessary technical equipment can be omitted. In this embodiment of the method according to the invention, it was surprisingly found that the changes achieved were very uniform both over the length of the textile substrate treated in each case and also over its thickness or over the circumference. This is attributed to the fact that, in the process according to the invention, radicals or ions are formed by the physical treatment only at the points at which the initiator is adsorbed or absorbed by the textile substrate, so that the actual yarn polymer at the points to which no initiator is adsorbed or absorbed remains largely unchanged.

If the textile substrate is opened as a winding body and subjected to a low-temperature plasma treatment or corona treatment, it is advisable to select a perforated cylindrical winding body, in particular a perforated metal sleeve.

A further embodiment of the method according to the invention, which is used in particular to introduce functional (reactive) groups in the yarn polymer, provides that the textile substrate is subjected to a low-temperature plasma treatment or corona treatment after the initiator has been applied. In this case, an inert gas also flows through this pile. This inert gas has the effect that corresponding radicals or ions are formed in the area in which initiator is adsorbed or absorbed on the textile substrate. This can be followed by a corresponding reaction with such compounds as, for example, oxygen, ammonia, carbon dioxide or sulfur dioxide, which can then be converted into the corresponding functional groups by a simple chemical reaction, for example by treatment with water, acids or alkalis are. These functional groups are then additionally formed on the fiber polymer and can be used to bind dyes or other substances, such as conventional equipment. For this purpose, noble gases and / or nitrogen are preferred as inert gas or inert gas mixtures.

In order to make the changes in properties achieved by the method according to the invention particularly uniform, it is advisable, in particular also in the case of very dense winding bodies or piles, to alternate the To flow through the winding body or the pile from the inside out and from the outside in with the gas (reactive gas, inert gas).

In principle, any desired starting material, such as, for example, polyamide, polyester, polypropylene, Nomex, glass, polyacrylonitrile, carbon and / or ceramic fibers, in each case alone or in a mixture with other synthesis, can be used as the textile substrate - and / or natural fibers. The method according to the invention can also be successfully applied to natural fibers such as wool, cotton, jute or the like.

It is particularly advantageous if the method according to the invention is used for sewing threads. It was found here that sewing threads which had been treated by the process according to the invention and in particular were equipped with the substances mentioned above have a significantly better sewing behavior, which was expressed in a correspondingly reduced frequency of thread breakage and in a higher number of buttonholes. The process according to the invention was also able to considerably improve the dyeability of sewing threads which are difficult to dye, for example those threads which have aramid fibers, Nomex fibers and / or polyalkylene fibers, in particular polypropylene fibers , especially since such sewing threads could then be dyed with basic dyes, acid dyes and / or reactive dyes depending on the functional groups introduced by the process according to the invention.

Here, the sewing threads mentioned above have the usual sewing thread constructions, i.e. it was therefore core yarns, multifilament yarns or filament / fiber yarns, which were possibly twisted.

Furthermore, these sewing threads can have the known construction of a intermingled yarn or a spun yarn, the titer of the aforementioned sewing threads being of the order of magnitude between 50 dtex x 2 (total titer 100 dtex) and 1,200 dtex x 3 (total titer 3,600 dtex).

Advantageous developments of the method according to the invention are specified in the subclaims.

The method according to the invention is explained in more detail below using two exemplary embodiments.

example 1

A polyester fabric with a width of 10 cm and a basis weight of 140 g / m ² was wound on a perforated sleeve with a winding height of 3 cm. The winding body was then inserted into a conventional laboratory dyeing system and there with a alcoholic solution (ethanol) of 50 g of benzoyl peroxide at 20 ° C for ten minutes.

After careful drying, the winding body was removed and placed in a vacuum chamber, where it was subjected to a low-temperature plasma treatment. Here, the conditions during the low-temperature plasma treatment were as follows:

Pressure before the low temperature plasma treatment: 5 Pa Pressure during low temperature plasma treatment: illustration 1 Frequency: 13.56 MHz Power density: 8 W / dm ³ Duration of the first and second treatment period: 40 seconds each Total duration of treatment: 10 mins Gas: oxygen

Subsequently, the wound body treated in this way was flowed through with water on the laboratory dyeing machine and then dyed in the usual manner with a conventional reactive dye (Levafix 2%).

The dyeing thus created was assessed colorimetrically, samples being taken from the lower winding layer, the middle winding layer and the upper winding layer (outer winding layer). Here it could be determined that there were neither color depth nor color differences, both visually and colorimetrically.

Furthermore, the rub fastness, the water fastness (heavy duty), the sweat fastness and the wash fastness were measured. None of these authenticity was objectionable.

Example 2

A Nm 25 x aramid fiber sewing thread was wound on a 1 kg bobbin and treated in a laboratory dyeing machine with a 5% strength hydrogen peroxide solution (30% hydrogen peroxide) at 25 ° C. for ten minutes.

The coil treated in this way was then mechanically dewatered and then gently dried.

The coil was then placed in an autoclave and subjected to a low-temperature plasma treatment under the following conditions:

Pressure before the low temperature plasma treatment: 5 Pa Pressure curve during the low-temperature plasma treatment: illustration 1 Frequency: 13.5 NHz Power density: 15 W / dm ³ Duration of the first and second treatment period: 40 seconds each Total duration of treatment: 25 minutes Gas: ammonia

The thread spool was then removed from the autoclave and transferred to the laboratory dyeing plant. There, water was first passed through the material for 2 minutes at room temperature. Thereafter, conventional dyeing was carried out using an acid dye (2% of a commercially available acid dye).

Samples of the inner layer, the middle layer and the outer layer were taken from the coil and the color was first assessed visually and colorimetrically. No color or color depth differences could be determined here.

Furthermore, comparative strength tests were carried out on the three layers mentioned above, with no differences in strength between the individual layers. The strength after the low temperature plasma treatment and the subsequent coloring was 95% of the strength of the starting material.

The fastness properties mentioned in Example 1 were also determined from the sewing threads treated according to Example 2. Here, these fastnesses were also satisfactory.

Claims (39)

1. A method for the modification of the properties of a textile substrate according to which an initiator decomposing into radicals and/or ions by a physical treatment is applied to the textile substrate and the physical treatment is carried out, characterized in that a heap of textile substrate or a wound package is manufactured from the textile substrate, that the heap of textile substrate, respectively the wound package is superfused by a gaseous initiator or a solution, dispersion or emulsion of the initiator and that simultaneously and/or thereafter the physical treatment is carried out, and that the radicals and/or ions hereby generated are brought into reaction with the textile substrate itself, with a substance applied hereon and/or with a gas surrounding the textile substrate.
2. The method according to claim 1, characterized in that the textile substrate is brought into reaction with at least one reactive gas surrounding the textile substrate, the reactive gas being preferably O₂, N₂O, O₃, CO₂, NH₃, SO₂, SiCl₄, CCl₄, CF₃Cl, CF₄, CO, hexamethyldisiloxane and/or H₂, or that the textile substrate is brought into contact with an inert gas, preferably with at least one noble gas and/or with nitrogen and/or with a mixture of the above mentioned gases.
3. The method according to claim 1 or 2, characterized in that at least one radically and/or ionically oligomerizable, respectively radically and/or ionically polymerizable substance is applied onto the textile substrate.
4. The method according to claim 3, characterized in that a substance is applied that comprises oligomerizable and/or polymerizable hydrocarbons, hydrocarbon copolymeres, hydrocarbon oligomeres, mixed hydrocarbon oligomeres, mixed hydrocarbon polymeres and/or derivatives thereof.
5. The method according to claim 3 or 4, characterized in that such a substance is selected that comprises oligomerizable and/or polymerizable compounds of the acrylic acid, acrylic acid cooligomeres, acrylic acid copolymeres, mixed acrylic acid oligomeres, mixed acrylic acid copolymeres and/or salts and/or derivatives thereof.
6. The method according to one of the claims 3 to 5, characterized in that a substance is selected that comprises of oligomerizable and/or polymerizable compounds of styrene, its derivatives, styrene cooligomeres, styrene copolymeres, mixed styrene cooligomeres, mixed styrene copolymeres and/or salts and/or derivatives thereof.
7. The method according to one of the preceding claims, characterized in that an initiator is selected which is on the basis of a persulphate, preferably a potassium persulphate and/ or an ammonium persulphate, a peroxide, preferably dibenzoyl peroxide, cumene hydroperoxide, cyclohexanone peroxide, di-tert.-butyl peroxide, cyclohexylsulphonylacetyl peroxide, an azo compound, preferably azodiisobutyric acid dinitrile, and/or an initiator which is on the basis of benzopinacol, diisopropyl percarbonate and/or tert.-butyl peroctoate.
8. The method according to one of the preceding claims, characterized in that a redox system, preferably potassium persulphate/sodium hyposulphite, hydrogen peroxide/iron-II-sulphate, cumene hydroperoxide/polyamine and/or benzoyl peroxide/N-dimethylaniline, is used as an initiator.
9. The method according to one of the preceding claims, characterized in that the textile substrate is swelled by applying a swelling agent before and/or during the application of the initiator.
10. The method according to one of the preceding claims, characterized in that a thermal treatment, a light irradiation, an α-, β-, γ-irradiation and/or an electrical treatment is selected as a physical treatment.
11. The method according to claim 10, characterized in that a low temperature plasma treatment is carried out as a physical treatment.
12. The method according to claim 11, charaterized in that the low temperature plasma treatment is carried out at a pressure between 5 Pa and 500 Pa.
13. The method according to claim 11 or 12, characterized in that the low temperature plasma treatment is carried out at a pressure between 20 Pa and 300 Pa, preferably between 70 Pa and 200 Pa.
14. The method according to one of the claims 11 to 13, characterized in that during the low temperature plasma treatment the pressure is set between around 5 Pa and around 120 Pa, preferably between around 20 Pa and around 120 Pa, during a first treatment period and that during a following second treatment period the pressure is set between around 80 Pa and around 250 Pa, preferably between around 100 Pa and around 200 Pa.
15. The method according to claim 14, characterized in that the first treatment period follows immediately after the second treatment period.
16. The method according to one of the claims 14 or 15, characterized in that the first and the second treatment period are repeated several times and one after the other.
17. The method according to one of the claims 14 to 16, characterized in that between the first and the second treatment period and between the second and the first treatment period the pressure is continuously increased, respectively decreased.
18. The method according to one of the claims 14 to 17, characterized in that a period of between 10 seconds and 160 seconds, preferably between 20 seconds and 60 seconds, is correspondingly selected for the first and the second treatment period.
19. The method according to one of the claims 12 to 18, characterized in that at the beginning of the low temperature plasma treatment a pressure being lower than the pressure during the low temperature plasma treatment is set and that thereafter a gas, preferably a reactive gas and/or an inert gas, is added until the required treatment pressure is achieved.
20. The method according to one of the claims 11 to 19, characterized in that the low temperature plasma treatment is carried out at a frequency of between 1 MHz and 20 MHz, preferably of 13,56 MHz.
21. The method according to one of the claims 11 to 19, characterized in that the low temperature plasma treatment is carried out at a frequency of 27,12 MHz, 40,68 MHz and/or 81,36 MHz.
22. The method according to one of the claims 11 to 21, characterized in that the low temperature plasma treatment is carried out at a power of between 200 W and 600 W.
23. The method according to one of the claims 11 to 22, characterized in that the low temperature plasma treatment is carried out at power density of between 2 W/dm³ and 25 W/dm³, preferably between 8 W/dm³ and 14 W/dm³.
24. The method according to one of the claims 11 to 19, characterized in that the low temperature plasma treatment is carried out at a frequency of 2,45 GHz, at a pressure of between 10^-1 up to 1.000 Pa, preferably between 70 Pa and 120 Pa, and at a power density of between 0,1 W/dm³ and 5 W/dm³, preferably between 1,5 W/dm³ and 3 W/dm³.
25. The method according to claim 10, characterized in that a corona treatment is carried out as physical treatment.
26. The method according to claim 25, characterized in that the corona treatment is carried out at a pressure of between 86,659 x 10³ Pa and 133,32 x 10³ Pa, preferably at a pressure between 33,325 x 10³ Pa and 113,324 x 10³ Pa.
27. The method according to claim 26, characterized in that during the corona treatment a pressure of between 86,659 x 10³ Pa and 99,99 x 10³ Pa is set during a first treatment period and that a pressure of between 99,99 x 10³ Pa and 113,324 x 10³ Pa is set during a second treatment period.
28. The method according to claim 27, characterized in that the first treatment period follows immediately after the second treatment period.
29. The method according to claim 27 or 28, characterized in that the first and the second treatment period are alternately repeated several times.
30. The method according to one of the claims 27 to 29, characterized in that between the first and the second treatment period and between the second and the first treatment period the pressure is continuously increased, respectively decreased.
31. The method according to one of the claims 27 to 30, characterized in that a period of between 10 seconds and 160 seconds, preferably between 20 seconds and 60 seconds, is correspondingly selected for the first and the second treatment period.
32. The method according to one of the claims 27 to 31, characterized in that before the corona treatment a pressure being lower than the pressure during the corona treatment is set and that thereafter a gas is added until the required treatment pressure is achieved.
33. The method according to claim 32, characterized in that a pressure of between 1.000 Pa and 10.000 Pa is set before the corona treatment.
34. The method according to one of the claims 10 to 33, characterized in that the low temperature plasma treatment respectively the corona treatment is carried out within a period of between 2 minutes and 30 minutes.
35. The method according to one of the preceding claims, characterized in that the textile substrate is wound up on a perforated tube, preferably on a perforated metal tube.
36. The method according to one of the preceding claims, characterized in that the heap of the textile substrate respectively the wound package of the textile substrate is superfused alternately from the outside to the inside and from the inside to the outside by a reactive gas and/or an inert gas.
37. The method according to one of the claims 10 to 36, characterized in that during or after the low temperature plasma treatment respectively the corona treatment the wound package is superfused by gaseous oxygen, carbon dioxide, sulphur dioxide and/or ammonia and thereafter by water, and that the material treated this way is dyed respectively printed with acid dyestuffs, basic dyestuffs or reactive dyestuffs.
38. The method according to one of the preceding claims, characterized in that a sewing thread is selected as a textile substrate.
39. The method according to claim 38, characterized in that a sewing thread consisting of aramid fibres and/or polyalkylene fibres, preferably polypropylene fibres, is cross wound, that thereafter the initiator is evenly adsorbed respectively absorbed at the sewing thread, that the low temperature plasma treatment respectively the corona treatment is carried out and that thereafter the sewing thread is dyed with an ionic dyestuff.

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