DE19736542A1 - Wool with anti-felting finish - Google Patents

Abstract

Wool with an anti-felting finish is obtained by subjecting dyed or undyed combed top wool to pretreatment with a low-pressure plasma and then treating it with an aqueous dispersion of self-dispersing isocyanate. The self-dispersing isocyanates have an isocyanate content of 1-25% and are obtained by reacting (A) polyisocyanates with an average NCO functionality of 1.8-4.2 with (B) polyalkylene oxide-alcohols, -amines and/or -thiols of formula R<1>R<2>N-(CHX-CHY-O)n-CHX-CHY-ZH (I) and optionally (C) other NCO- reactive compounds with actual or potential anionic or cationic groups, in which n = 3-70; X, Y = H or methyl (if X or Y is methyl, the other must be H); R<1>, R<2> = 1-6C alkyl or acyl (if R<1> = acyl, R<2> may also be H), and R<1> + R<2> may be tetra-, penta- or hexa-methylene, optionally with one or two CH2 groups replaced by O and/or NH and/or with 1 or 2 CH2 groups substituted with methyl; Z = O, S or NH . An Independent claim is also included for self-dispersing isocyanates as described above.

Description

The invention relates to felt-free finished wool, a process for its production by a) pretreatment with a low-pressure plasma b) post-treatment with aqueous dispersions of self-dispersing isocyanates and for this purpose usable water-dispersible isocyanates.

Isocyanates for non-felt finishing of textiles have long been known and can for example, as described in DE-OS 19 04 802, in organic solvents are used or, as described in DE-OS 17 69 121, in aqueous dispersion with the help of emulsifiers. Both organic solvents and optionally wastewater-polluting emulsifiers are today from ecological and industrial hygiene considerations out of date. The following is therefore either of self-dispersing isocyanates or formulations, which with as few solvents or emulsifiers as auxiliaries and additives come.

FR 1,542,831 describes the treatment of textile materials with baths Polymers or copolymers of vinyl or divinyl compounds, an aqueous one Contain dispersion of isocyanates, ammonium salts or metal salts and surfactants. Auxiliary solvents are used here. DE-OS 17 94 221 describes the Be act of fiber materials with isocyanate prepolymers that are still free iso contain cyanate groups; this equipment can be used in solvents (perchlorethylene) or in aqueous emulsion using auxiliary emulsifiers become. US-P 3,847,543 discloses a process for the non-felting of wool, in which the following are present in aqueous dispersion: aliphatic isocyanates, OH-functional crosslinkers and organometallic catalysts. Although this ver drive in the aqueous phase, auxiliary solvents and emulsifiers are still required. DE-OS 44 15 451 (WO 95/30045) describes a method in which water-dispersible isocyanates can be used to make wool free of felt. Here you can work without solvents and without an emulsifier, because the The isocyanates used are water-dispersible. The examples describe it  inventive method, however, in that the wool first a Vorbe action by oxidizing agents, followed by a reduction treatment, is subjected before the water-dispersible isocyanates are used. Of course, this pre-treatment causes wastewater, which complies with regulations must be neutralized and clarified.

On the contrary, the present invention caused by the above treatment by low pressure plasma does not contain any waste water and is ecologically positive to judge. Surprisingly, it was found that it was more oxidative and / or reducing pretreatment agent is not required and a very good felt-free Finishing on wool can be achieved if treated with water before dispersed isocyanates, a low-pressure plasma treatment is carried out.

The present invention relates to felt-free finished wool, which is characterized in that dyed or undyed wool sliver

• (a) exposed to low pressure plasma in a pretreatment and
• b) aftertreated with aqueous dispersions of self-dispersing isocyanates becomes.

Another object of the present invention is a process for the felt-free armor of wool, which is characterized in that colored or undyed wool comb

• (a) exposed to low pressure plasma in a pretreatment and
• b) aftertreated with aqueous dispersions of self-dispersing isocyanates becomes.

The self-dispersing isocyanates are also the subject of the invention; they have an isocyanate content of 1 to 25% by weight, calculated as NCO (molecular weight 42) and based on the total weight of the isocyanates, and can be obtained by reaction in any order of:

• I) organic polyisocyanates with an average NCO functionality of 1.8 to 4.2 with
• II) Polyalkylene oxide alcohols, amines and / or thiols of the formula
  in the
  n represents a number from 3 to 70,
  X and Y are hydrogen or methyl with the proviso that in the case of methyl only one of the radicals X and Y is methyl and the other is hydrogen,
  R ¹ and R ² independently of one another are straight-chain or branched C ₁ -C ₆ -alkyl or C ₁ -C ₆ -acyl, where in the case that R ^{1 is} acyl, R ^{2 can} also be hydrogen and R ¹ and R ² together can represent tetramethylene, pentamethylene or hexamethylene, in which one or two methylene groups can be replaced by O and / or NH and / or one or two methylene groups can be substituted by methyl, and
  Z represents O, S or NH,
  and if necessary with
• III) further NCO-reactive compounds which are anionic or cationic or potentially contain anionic or cationic groups.

The term "self-dispersing" in the present context means that the Mixtures in a concentration of up to 70% by weight, preferably up to 50% by weight result in finely divided dispersions with particle sizes of <500 nm (measured using an ultracentrifuge).

Examples of possible starting materials for the self-dispersing isocyanates are:

• I) Unmodified, aliphatic, cycloaliphatic, araliphatic or aromatic isocyanates of the NCO functionality from 1.8 to 4.2. Aliphatic and cycloaliphatic polyisocyanates are preferably used which have uretdione and / or isocyanurate and / or allophanate and / or biuret and / or oxadiazine structures and which are prepared in a manner known per se from aliphatic, cycloaliphatic, araliphatic or aromatic diisocyanates can. For example: 1,4-diiso cyanatobutane, 1,6-diisocyanatohexane, 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1,6- diisocyanatohexane, 1,3- and 1,4-diiso cyanatocylohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclo hexane, 1-isocyanato-1-methyl-4-isocyanatomethyl-cyclohexane and 4,4-diiso cyanato-dicyclohexylmethane or any mixture of such diisocyanates.
  The preferred uretdione, isocyanurate, allophanate, oxadiazine group-containing reaction products of these diisocyanates are essentially trimeric 1,6-diisocyanatohexane or 1-isocyanato-3,3,5-tri methyl-5-isocyanatomethyl-cyclohexane and polyisocyanate mixtures consisting of the corresponding higher homologues and containing isocyanurate groups and optionally uretdione groups with an NCO content of 19 to 24% by weight. The corresponding, largely uretdione group-free, isocyanate group-containing polyisocyanates of the stated NCO content are particularly preferably used, as they are known per se, catalytic trimerization of 1,6-diisocyanatohexane or 1-isocyanato-3,3,5-tri methyl -5-isocyanatomethyl-cyclohexane are obtained with formation of isocyanurate and which preferably have an (average) NCO functionality of 3.2 to 4.2: Preference is also given to the reaction of 1,6-diisocyanato hexane with a deficit of water Trimeric polyisocyanates obtained in a known manner and having essentially biuret groups and having an NCO content of 19 to 24% by weight. Other suitable polyisocyanates are aliphatic or aromatic diisocyanates such as hexamethylene diisocyanate, tolylene diisocyanate, 1,5-diisocyanato naphthalene, diphenylmethane diisocyanate and their higher homologues with uretdione, isocyanurate, allophanate and biuret groups.
• II) Among the polyalkylene oxide ether alcohols, ether amines and / or ether thiols of the formula (I), the polyalkylene oxide ether alcohols are preferred.
  The polyalkylene oxide ether alcohols are mono- or polyvalent polyalkylene oxide ether alcohols containing on average 3 to 70, preferably 6 to 60 alkylene oxide units per mole, as are obtainable in a manner known per se by alkylation of suitable starter molecules. Any secondary amines or acid amides can be reacted as starter molecules to produce these polyalkylene oxide ether alcohols. Also suitable for the alkoxylation reaction are heterocyclic nitrogen compounds such as morpholine. Identical compounds can also be obtained by using morpholinoethanol as a starter for the ethoxylation reaction. Acylation products of ethanolamine, such as acetylethanolamine, can also be used as starters. Alkylene oxides suitable for the alkoxylation reaction are ethylene oxide and propylene oxide, which can be used individually or in any order or in a mixture in the alkoxylation reaction.
• The polyalkylene oxide ether alcohols are either pure polyethylene oxide polyethers, pure polypropylene polyethers or mixed polyalkylene oxide polyethers which have at least one polyether sequence which have at least 3, generally 3 to 70, preferably 6 to 60 and particularly preferably 7 to 20 alkylene oxide units, and whose alkylene oxide units consist of at least 60 mol%, preferably at least 70 mol%, of ethylene oxide units. Preferred polyalkylene oxide polyether alcohols of this type are monofunctional polyalkylene oxide polyethers started on an aliphatic, nitrogen-containing starter according to structure (I), which on average contain 6 to 60 ethylene oxide units.
  The ether alcohols can be obtained by reaction with H ₂ S ether thiols (Z = S) and with NH ₃ ether amines (Z = NH).
• III. In the case of the further NCO-reactive compounds which are anionic or contain cationic and / or potential anionic or cationic groups ten, it is:
• i) Hydroxyl-functional or amino-functional compounds with ter tiär Amino groups, as they be in DE-OS-43 19 571 extensively have been written;
• ii) hydroxyl-functional or amino-functional compounds with carb oxyl or sulfonic acid groups, as detailed in DE-19 520 092 have been described;
• iii) hydroxyl-functional or amino-functional compounds with carb oxylate or sulfonate groups, their counterions from metal cations the alkali or alkaline earth group or ammonium, as described in DE 195 20 092 have been described in detail;
• iv) hydroxyl-functional or amino-functional compounds with ammo nium ions, which in a known manner by Akylierung or Pro  Toning, as described in EP-A 0 582 166, from the tertiary Amino groups of the compounds i) are available.

Of course, any mixtures of NCO-reactive groups, if provided Chemically useful, for example from groups i) and iv), about obtainable from partial alkylation of tertiary amino groups, or for example from groups ii) and iv) can be used according to the invention.

The unmodified polyisocyanates to be used according to the invention can also be used in combination with external ionic or nonionic emulsifiers. Such emulsifiers are described, for example, in Methods of Organic Chemistry, Houben-Weyl, Vol. XIV / 1, Part 1, pages 190-208 Thieme-Verlag, Stuttgart (1961), in US Pat. No. 3,428,532 and EP-A 0 013 112. The emulsifiers are used in an amount which ensures dispersibility. If polyisocyanates I are first reacted with polyalkylene oxide polyether alcohols, this reaction can be carried out in a manner known per se, while maintaining an NCO / OH equivalence ratio of at least 2: 1, generally from 4: 1 to about 1000: 1, with polyethers -modified polyisocyanates with an average NCO functionality from 1.8 to 4.2, preferably from 2.0 to 4.0, a content of aliphatic or cycloaliphatic isocyanate groups from 12.0 to 21.5% by weight and a content of ethylene oxide units arranged within polyether chains (calculated as C ₂ H ₄ O, molecular weight = 44 g / mol) of 2 to 20% by weight, where the polyether chains have a static average of 3 to 70 ethylene oxide units.

The output components can be in any order with the exclusion of Moisture, preferably without solvent, are implemented. With increasing The amount of component (II) achieves a higher viscosity of the end product, so that in certain cases (when the viscosity increases sharply) a solvent can be added, which is preferably miscible with water, but opposite the polyisocyanate is inert. Suitable solvents of this type are: alkyl ether acetates, glycol diesters, toluene, carboxylic acid esters, acetone, methyl ethyl ketone, Tetrahydrofuran and dimethylformamide.  

By using catalysts known per se, such as dibutyltin dilaurate, tin (II) octoate or 1,4-diazabicyclo [2.2.2] octane, in amounts of 10 to 1000 ppm, based on the reaction components, the reaction can be accelerated. The reaction is carried out in the temperature range up to 130 ° C., preferably in the range between 10 ° C. and 100 ° C., particularly preferably between 20 ° C. and 80 ° C. The reaction is followed by titration of the NCO content or by measuring the IR spectra and evaluating the NCO band at 2260-2275 cm ^-1 and is complete when the isocyanate content is not more than 0.1% by weight above the Value that is achieved with a given stoichiometry with complete conversion. As a rule, response times of less than 24 hours are sufficient. The solvent-free synthesis of the polyisocyanates to be used according to the invention is preferred.

In a further embodiment, it is also possible to mix the polyisocyanate mixtures to be used according to the invention by mixing

• 1) unmodified polyisocyanates I)
• 2) polyisocyanates obtained by reacting polyisocyanates I) with the under III) called NCO-reactive compounds, the ratio of equivalents the groups of III) which are reactive toward isocyanates to those used NCO groups of component II) is 1: 1 to 1: 1000, are obtained and
• 3) polyisocyanates obtained by reacting polyisocyanates I) with poly alkylene oxide polyether alcohols, amines and / or thiols II), which Equivalent ratio of the groups reactive towards isocyanates Component II to the NCO groups of component I) used 1: 1 to Is 1: 1000, can be obtained

to manufacture. The number of NCO-reactive equivalents are polyethers content, the NCO content and the NCO functionality through appropriate weights adjusted by the expert so that the mixture obtained for the Wasserdisper  has the required composition, in particular the already ge named preferred areas apply.

The self-dispersible polyisocyanate mixtures are technically easy to handle and Storage stable for many months with the exclusion of moisture.

According to the invention, the self-dispersible polyisocyanate mixtures are preferred used without organic solvents. They are at temperatures up to 100 ° C very easy to emulsify in water. The active substance content of the emulsion can be up to 70% by weight be. However, it is more advantageous to have emulsions with an active ingredient content to produce from 1 to 50 wt .-%, which may then continue before the metering point can be diluted. For emulsification, those customary in technology are suitable Mixing units (stirrer, mixer with rotor-stator principle and e.g. high pressure emul yaw machines).

The preferred self-dispersible polyisocyanates are self-emulsifying, i.e. H. she can be easily added to the water phase without the application of high shear forces emulsify. A static mixer is usually sufficient. The emulsions obtained possess a processing time of up to 24 hours, depending on the structure of it polyisocyanates to be used according to the invention, in particular their ba content depends on the N atoms.

Examples A) Self-dispersing isocyanates Self-dispersing isocyanate 1 (for comparison)

85 parts by weight of an isocyanate with an NCO content of 22.5%, consisting of essentially on trimeric hexamethylene diisocyanate, were at 60 ° C with 15 parts by weight len of a polyethylene glycol monomethyl ether with an average molecular weight of 350 implemented. The resulting product had an NCO content of 17% and a viscosity of 1500 mPa.s at 25 ° C. The product let itself through simple stirring with a glass rod very well in a beaker with water disperse. Computational NCO functionality: F = 2.70.

Self-dispersing isocyanate 2 (according to the invention)

85 parts by weight of an isocyanate with an NCO content of 22.5%, consisting essentially of trimeric hexamethylene diisocyanate, were at 60 ° C. with 15 parts by weight of an ethylene oxide polyether started on morpholine and having an average molecular weight of 420 implemented. The resulting product had an NCO content of 16.5% and a viscosity of 2550 mPa.s at 25 ° C.
Computational NCO functionality: F = 2.76.

Self-dispersing isocyanate 3 (according to the invention)

65 parts by weight of an isocyanate with an isocyanate content of 22.5%, consisting of essentially from trimeric hexamethylene diisocyanate, were at 60 ° C with 35 parts by weight len of an ethylene oxide polyether described above and started on morpholine implemented. The product had an NCO content of 10.9% and a viscosity of 4400 mPa.s at 25 ° C. Computational NCO functionality: F = 2.52.  

Self-dispersing isocyanate 4 (according to the invention)

50 parts by weight of an isocyanate with an isocyanate content of 22.5%, consisting of essentially from trimeric hexamethylene diisocyanate, were at 60 ° C with 50 parts by weight len of an ethylene oxide polyether started on morpholine and described above implemented. The product had an NCO content of 6.2% and a viscosity of 7080 mPa.s at 25 ° C. Computational NCO functionality: F = 1.84.

The self-dispersing isocyanates according to the invention were also very suitable disperse with water using a glass rod in a beaker.

B) Trials for felt-free finishing

To compare the isocyanates on felt-free finish, a wet wool comb was subjected to a plasma treatment, as described in DE 196 16 776, and then treated with the exhaust process with a buffered aqueous dispersion of the self-dispersing isocyanates described under A). The wool comb was examined after rinsing and drying according to the "Aachener felt ball test" according to IWTO 20-69. A comb tensile test was used under felt-forming conditions; the diameter of the resulting ball is a measure of the felt tendency of the finished wool samples (the larger the better). The results are shown in the following table:

Claims (8)

1. Felt-free finished wool, characterized in that dyed or uncoloured wool sliver

• (a) exposed to low pressure plasma in a pretreatment and
• b) nachbe is treated with aqueous dispersions of self-dispersing isocyanates.

2. Felt-free finished wool according to claim 1, characterized in that the self-dispersing isocyanates used for the aftertreatment have an isocyanate content of 1 to 25%, calculated as NCO with the mol weight 42 and based on the total weight of the isocyanates, and by reaction in any order from

• I) with organic polyisocyanates with an average NCO functionality of 1.8 to 4.2
• II) Polyalkylene oxide alcohols, amines and / or thiols of the formula
  in the
  n represents a number from 3 to 70,
  X and Y are hydrogen or methyl with the proviso that in the case of methyl only one of the radicals X and Y is methyl and the other is hydrogen,
  R ¹ and R ² independently of one another are straight-chain or branched C ₁ -C ₆ -alkyl or C ₁ -C ₆ -acyl, where, in the case where R ^{1 is} acyl, R ^{2 can} also be hydrogen and R ¹ and R ² together can represent tetramethylene, pentamethylene or hexamethylene, in which one or two methylene groups can be replaced by O and / or NH and / or one or two methylene groups can be substituted by methyl, and
  Z represents O, S or NH,
  and if necessary with
• III) further NCO-reactive compounds which contain anionic or cationic or potentially anionic or cationic groups,
  are available.

3. Self-dispersing isocyanates with an isocyanate content of 1 to 25%, calculated as NCO with a molecular weight 42 and based on the total weight of the isocyanates, obtainable by reaction in any order from

• I) with organic polyisocyanates with an average NCO functionality of 1.8 to 4.2
• II) Polyalkylene oxide alcohols, amines and / or thiols of the formula
  in the
  n represents a number from 3 to 70,
  X and Y are hydrogen or methyl with the proviso that in the case of methyl only one of the radicals X and Y is methyl and the other is hydrogen,
  R ¹ and R ² independently of one another are straight-chain or branched C ₁ -C ₆ -alkyl or C ₁ -C ₆ -acyl, in which case; that R ^{1 is} acyl, R ^{2 can} also be hydrogen and where R ¹ and R ² together can represent tetramethylene, pentamethylene or hexamethylene, in which one or two methylene groups can be replaced by O and / or NH and / or one or two methylene groups may be substituted by methyl, and
  Z represents O, S or NH,
  and if necessary with
• III) further NCO-reactive compounds which contain anionic or cationic or potentially anionic or cationic groups.

4. Felt-free finished wool according to claim 2, characterized in that the organic polyisocyanates I) aliphatic, cycloaliphatic, araliphatic are table or aromatic isocyanates.   5. Felt-free finished wool according to claim 2, characterized in that the polyalkylene oxide alcohols, amines and / or thiols II) polyether chains one have average molecular weight of up to 3500 (number average) and these are made up of alkylene oxide units. 6. Felt-free finished wool according to claim 2, characterized in that the NCO-reactive compounds III) hydroxyl, amino and / or mer have capto groups and additionally tertiary amino groups or their protonated or alkylated variants or carboxyl groups and / or sulfone acid groups or carboxylate or sulfonate obtained by salt formation may contain groups. 7. A method for felt-free finishing of wool, characterized in that colored or uncolored wool roving

• (a) exposed to low pressure plasma in a pretreatment and
• b) nachbe is treated with aqueous dispersions of self-dispersing isocyanates.

8. A method for felt-free finishing of wool according to claim 7, characterized ge indicates that the aftertreatment b) before in step a) treated dyed or undyed wool comb discontinuously in Pull-out process or continuously by dipping, roller application, foular dieren, spraying or spraying.