DE19756906B4 - Use of a composition for coating textile materials and method therefor - Google Patents

Abstract

Use of a composition comprising:
(A) a layer-forming organosol formed by cohydrolysis of tetraalkoxysilanes Si (OR ¹ ) ₄ , trialkoxysilanes R ² Si (OR ¹ ) ₃ and / or dialkoxysilanes R ³ ₂ Si (OR ¹ ) ₂ , where R ¹ and R ^{3 are} alkyl radicals 1 to 4 C atoms and R ^{2 is} an alkyl radical having 1 to 18 C atoms or a fluoroalkyl radical having 1 to 18 C atoms or an epoxy-functionalized alkyl or cycloalkyl radical, in an organic solvent,
(B) an aluminum or zirconium halide in an aqueous-organic solvent, and
(C) a crosslinking compound having at least 2 hydroxyl groups,
for coating textile materials.

Description

The The invention relates to the provision of a coating agent for textile Materials that modify the absorption and reflection behavior and to improve the physico-mechanical properties the coated or impregnated Materials can be used.

It is well known that currently numerous molded parts and articles of daily use made of polymer plastics equipped with covers to protect them from mechanical or chemical damage. there is an important requirement that the coatings hard, abrasion resistant and ecological should be safe. This requirement is from the commercial ones organic lacquer coatings only insufficiently fulfilled. A coating with inorganic coatings required one so far elaborate vacuum technology. The temperatures in such processes are very high, so that one Application for organic substrates is only conditionally possible. Besides that is this technique device- and energy consuming, discontinuous and unsuitable for complicated geometric bodies. Therefore, there is a demand for improved surface modification methods of polymeric products.

In similar One is endeavored in the textile technology, the physical-mechanical Improve properties of tissues and through aftertreatments to give the fabrics more advantageous properties ("textile finishing"). To call are here, for example, the improvement of crease resistance, Obtaining a specific hydrophobicity of the tissue or achieving it a flameproof equipment etc. To that must be Substrate either by a chemical reaction and / or by adsorption be modified to the substrate. These procedures are often technical very elaborate, ecological not safe or very expensive. Another problem is in the In the case of adsorptive processes, anchorage is not sufficiently permanent on the fiber materials, so that the relax functional properties during use.

by virtue of the defects mentioned one seeks new, cost-effective, low-energy, ecological advantageous methods for surface modification of tissues and plastics to develop the utility properties to increase. As a new method for producing thin metal oxide coatings on vacuum-free Way offers the sol-gel technique.

For this purpose, by hydrolysis of metal alkoxides stable metal oxide sols ago (1), the thin metal oxide gel films form on any carriers by concentration during drying (2), eg Me (OR) _n + n / 2 H2O -> (MeO _m ) _sol + n ROH (1) (MeO _m ) _sol -> (MeO _m ) _gel (2) (Me = metal eg Si, Ti, Zr, Sn, Al, R = organic radical, eg alkyl, acyl)

The resulting pure metal oxide coatings are mechanically not very stable, since during the film forming process, a strong shrinkage process takes place and the degree of crosslinking is low. For this reason, for example, impregnations of textile fibers with Al ₂ O ₃ sols ( JP 69017595 and JP 02196884 ) or dispersions ( US 4676928 A ) or SiO ₂ -quasazoles ( EP 0095922 ) Too few abrasion resistant coatings.

Therefore one tries at present, by modifying the metal oxide sol structure the mechanical stability and wear resistance improve the formed metal oxide gel films.

One way is to use mixtures of different metal alkoxides to produce cross-linked metal oxide gels, eg SiO ₂ with Al ₂ O ₃ ( US 5336560 A . US 5,324,544 ), with TiO ₂ or ZrO ₂ ( DE 421 7432 A1 ) or their combination ( US 5262 362 A ). Similarly, the resistance to abrasion by the addition of Al ₂ O ₃ ( US 5595945 ) or other ceramic powder ( DE 430 7665 A1 ) to improve.

Another way is the organic modification of the metal oxide sols z. By direct chemical bonding of alkoxysilane groups with vinyl polymers ( EP 0065388 ) or composite formation with different polymers (WO 9301 226, EP 0047160 ) or resins ( EP 497560 A2 ). The mechanical properties can be significantly improved by condensing organofunctionalized alkoxysilanes (eg with acrylate groups or epoxide groups) and thermally crosslinking them after gel formation. For example, systems of epoxysilanes with bisphenols ( DE 352 0749 A1 ) or polycarboxylic acids ( EP 0407174 B1 ) when Crosslinker proposed. The coatings obtained in both ways do not meet in all cases the demands that are made in terms of adhesion, abrasion resistance to mechanically stressed consumer goods and the storage stability of the brine used.

The practical problem is that highly crosslinking systems usually have low lifetimes, since even after the preparation of the coating solutions, a slow crosslinking begins, which leads to an increasing solidification before the coating process. On the other hand, lifetime-stable coating solutions often provide unsatisfactory mechanical values since the degree of crosslinking of the layer is insufficient. This problem has recently been solved by DE 196 20 668 C1 ) that two modified metal oxide sols were combined, which are effectively crosslinked only when heated. These thermally curable multicomponent coatings are only of limited suitability for the coating of textile or polymeric materials because of their low thermal stability.

The The object of the invention is to provide new possibilities of coating agents for find sol-gel-based textile materials that ensure long-term stability and yet effective crosslinking during layering already at room temperature.

These The object is achieved by the use of a composition according to claim 1 and the method according to claim 13 solved. Advantageous embodiments The invention will become apparent from the dependent claims. Surprisingly In particular, this task could be accomplished by simple means to be solved the existence Coating agent is used, which consists of 3 long-lasting components consists (hereinafter referred to as component A, B and C), the are mixed immediately before the coating process, and after the coating by a strong adsorptive interaction with during the substrate the drying phase to excellent adhesion and good physical-mechanical Properties lead.

• – das Tetraalkoxysilan (I, R¹ = Alkylreste mit 1–4 C-Atomen) erhöht durch Cokondensation mit (II) und (III) die Stabilität und das Standzeitverhalten der Komponente A und verbessert die Schichtqualität,
• – das Trialkoxysilan R²Si(OR¹)₃ funktionalisiert durch die Wahl des Restes R² das Beschichtungsmittel, z.B. R² = Alkylrest mit 1–18 C-Atomen erhöht die Hydrophobie der Schicht, R² = Fluoralkylrest mit 1–18 C-Atomen verstärkt die schmutz- und wasserabweisende Wirkung der Beschichtung, R² = epoxyfunktionalisierter Alkyl- oder Cycloalkylrest ermöglicht durch die Vernetzung mit Komponente 3 eine zusätzliche thermische Nachhärtung,
• – das Dialkoxysilan R³Si(OR¹)₂ (III, R³ = Alkylrest mit 1–4 C-Atomen) erhöht die Flexibilität und Elastizität der Beschichtung.

The component A according to the invention consists of a solution which by acid or alkali catalyzed hydrolysis of a mixture of a tetraalkoxysilane Si (OR ¹ ) ₄ (I), one or more Trialkoxysilane R ² Si (OR ¹ ) ₃ (II) and / or a Dialkoxysilane R ³ Si (OR ¹ ) ₂ (III) is formed in an organic solvent. The 3 components have the following function:

• The tetraalkoxysilane (I, R ¹ = alkyl radicals having 1-4 C atoms) increases the stability and the service life of the component A by cocondensation with (II) and (III) and improves the layer quality,
• - The trialkoxysilane R ² Si (OR ¹ ) ₃ functionalized by the choice of the radical R ^2, the coating agent, for example R ² = alkyl radical having 1-18 carbon atoms increases the hydrophobicity of the layer, R ² = fluoroalkyl radical with 1-18 C Atoms enhance the dirt and water-repellent effect of the coating, R ² = epoxy-functionalized alkyl or cycloalkyl radical allows crosslinking with component 3 additional thermal post-curing,
• - The dialkoxysilane R ³ Si (OR ¹ ) ₂ (III, R ³ = alkyl radical with 1-4 C-atoms) increases the flexibility and elasticity of the coating.

to Preparation of component A are advantageous for cohydrolysis Mixtures of 10 parts by weight of a tetraalkoxysilane (I), 0.1 up to 10 parts by weight of one or more trialkoxysilanes (II) and / or 0.1 to 5 parts by weight of a dialkoxysilane (III). The hydrolysis can be effected both by dilute acids, e.g. diluted hydrochloric acid, or diluted Alkalis, such as aqueous ammonia or caustic soda. As a solubilizer, water-miscible solvent such as low molecular weight alcohols and ketones, cyclic ethers, alkyl glycols or acetonitrile.

• – die Metallsalze vernetzen bzw. cokondensieren mit der Komponente A und führen dadurch einer effektiven Verfestigung der Beschichtungen während des Trocknungsprozesses bereits bei Raumtemperatur,
• – die basischen Metallsalze wirken bekanntermaßen als Beize (insbesondere für textile Flächen) und verbessern die Hafteigenschaften der Beschichtung, und ggf. die Färbbarkeit,
• – die Kombination der Komponenten A und B liefert bei einer zusätzlichen Temperung infolge Alumosilikatbildung zu einer weiteren Verbesserung der physikalisch-mechanischen Eigenschaften (Härte, Abrieb).

Component B according to the invention consists of an aluminum or zirconium halide, preferably aluminum hydroxide chloride or zirconium chloride, in an aqueous-organic solvent. For example, it is possible to prepare a 10% solution in 80% ethanol with aluminum hydroxide chloride (commercially available, for example, as Locron S / Clariant). Component B has 3 important functions:

• The metal salts crosslink or co-condense with the component A and thereby lead to effective solidification of the coatings during the drying process even at room temperature,
• The basic metal salts are known to act as stains (in particular for textile surfaces) and improve the adhesive properties of the coating, and optionally the dyeability,
• - The combination of components A and B provides at an additional tempering due aluminosilicate formation to a further improvement of the physico-mechanical properties (hardness, abrasion).

The component C according to the invention consists of a crosslinking compound having at least 2 hydroxyl groups. Tris (hydroxymethyl) propane, 2,2-bis- (4-hydro xy-phenyl) propane, bis (4-hydroxyphenyl) sulfone, hydroxypropyl cellulose or polydimethylsiloxane diol. The polyols mentioned improve the leg effect of the metal salts at room temperature and offer the possibilities of thermal post-curing by three-dimensional crosslinking when using epoxide group-containing trimethoxysilanes in component A.

The proportions the 3 components to each other as well as the solvent can in wide limits are varied. Preferably, based on the respective solids 20 parts by weight A with 1 to 20 Parts by weight of B and 1 to 5 parts by weight of C mixed. It is appropriate, the Mixing of the stable components A, B and C only immediately before to carry out the coating process, a slow increase in viscosity to exclude the paint as a result of incipient crosslinking. The Extent of viscosity increase after mixing is different in concentration and the mixing ratio the components A and B dependent.

The Coating of the textile materials can by all usual and known coating techniques such as padding, dipping, spray or watering or by appropriate impregnation techniques respectively. The layers show after removal of the solvent by a drying process (advantageous in a circulating air stream) good mechanical properties (Hardness, Abrasion). If the substrates used are suitable, the layer may after coating, gelation and removal of the solvent thermally cured become. For this purpose, the coated object should be heated to at least 80 ° C to 120 ° C. The lower the temperature, the longer the tempering should take place.

• 1. in der guten Haftung und in verbesserten mechanischen Eigenschaften (Härte, Abriebfestigkeit) der beschichteten Materialien bereits nach Trocknung bei Raumtemperatur
• 2. in der hohen Lagerstabilität der Einzelkomponenten A, B und C
• 3. in der Möglichkeit, bei geeigneten Substraten eine thermische Nachhärtung durchzuführen,
• 4. in der Möglichkeit, durch Veränderung des Mischungsverhältnisses der Komponenten A:B:C die Gebrauchswerteigenschaften (z.B. Hydrophobie) der beschichteten Materialien maßgeschneidert an den späteren Verwendungszweck anzupassen.
• 5. in der Möglichkeit, die Beschichtungsmittel für spezielle Anwendungen auch problemlos zu modifizieren, indem vor der Beschichtung spezielle wasser- oder alkohollösliche Stoffe zugemischt werden. (a) durch den Zusatz von Farbstoffen kann eine Farbgebung der beschichteten textilen Materialien erfolgen, z. B. durch Zugabe von 2-Methoxy-4-amino-azobenzol oder 4-(3-Methylphenylamino)-azobenzen können stabile bronze- oder goldfarbene Überzüge erzeugt werde. Durch den Zusatz z.B. von Ethylviolett, Brilliantgrün oder Rhodamin 6G lassen sich dekorative Überzüge in den Farben blau, grün und rot erzeugen. (b) durch den Zusatz biozider Stoffe (z.B. Borsäure, Benzoesäure, quartäre Ammoniumsalze, kolloidales Silber oder Silberverbindungen, die auf chemischem, thermischem oder photolytischem Weg in der Schicht in kolloidales Silber umgewandelt werden) lassen sich Schichten mit biozider Wirkung herstellen, (c) durch den Zusatz nanopartikulärer magnetischer Ferrit-Partikel (γ-Fe₂O₃) kann man magnetische Materialien herstellen, (d) durch den Zusatz von 1–20 Gewichtsanteilen alkohollöslicher Naturharze, z.B. von Kolophonium, Schellack oder Copal, bezogen auf den Feststoffanteil, kann man die Barrierewirkung der Beschichtungen gegenüber Gasen (O₂, CO₂) und leichtflüchtigen organischen Stoffen (z.B. flüchtigen Kohlenwasserstoffen) erhöhen.

The advantages of the coating composition of the invention over the previously known coatings:

• 1. in the good adhesion and in improved mechanical properties (hardness, abrasion resistance) of the coated materials already after drying at room temperature
• 2. in the high storage stability of the individual components A, B and C.
• 3. the possibility of carrying out a thermal post-curing with suitable substrates,
• 4. the possibility of customizing the utility properties (eg hydrophobicity) of the coated materials by changing the mixing ratio of the components A: B: C to the later intended use.
• 5. the possibility of easily modifying the coating materials for special applications by admixing special water- or alcohol-soluble substances before coating. (A) by the addition of dyes can be done a coloring of the coated textile materials, for. B. by the addition of 2-methoxy-4-amino-azobenzene or 4- (3-methylphenylamino) -azobenzene can be produced stable bronze or gold-colored coatings. The addition of eg ethyl violet, brilliant green or rhodamine 6G makes it possible to produce decorative coatings in the colors blue, green and red. (b) by the addition of biocidal substances (eg boric acid, benzoic acid, quaternary ammonium salts, colloidal silver or silver compounds which are converted into colloidal silver in the layer by chemical, thermal or photolytic means) it is possible to produce biocidal layers, (c) by the addition of nanoparticulate magnetic ferrite particles (γ-Fe ₂ O ₃ ) can produce magnetic materials, (d) by the addition of 1-20 parts by weight of alcohol-soluble natural resins, such as rosin, shellac or copal, based on the solids content, can increase the barrier effect of the coatings to gases (O ₂ , CO ₂ ) and volatile organic compounds (eg volatile hydrocarbons).

The applications The paints are due to the good stability and the excellent mechanical properties Layer properties very versatile. Particularly suitable are the Coating for the mechanical and chemical protection of textile Materials.

specific Applications of the coating agent are textile dyeings with high color fastness, to protect textiles against ultraviolet Radiation; for furnishing textiles with microwave-absorbing or -reflecting or IR-absorbing or reflective properties; for the creation of textiles with improved wear characteristics (eg production of abrasion resistant seat fabrics); for hydrophobing of fibers and polymer surfaces and improving the dirt-repellent effect as well as the creation of textiles with magnetic properties.

embodiments

1. Preparation of the component A:

• A1: To a mixture of 27 ml tetraethoxysilane (TEOS), 9 ml of 3-glycidyloxypropyltrimethoxysilane (GLYMO), 60 ml of ethanol 8 ml of 0.01N HCl are added dropwise and 20 hrs. At room temperature touched. The result is a water-clear stable sol.
• A2: To a mixture of 27 ml of TEOS, 27 ml of dimethyl diethoxysilane (DDS), 18 ml GLYMO, 60 ml ethanol, add 15 ml 0.01N HCl in 60 ml Ethanol added dropwise and stirred for 20 hrs. At room temperature. It creates a water-clear stable sol.
• A3: To a mixture of 70 ml of tetraethoxysilane (TEOS), 30 ml of methyltriethoxysilane, 420 ml of 96% ethanol add 20 ml of 0.01N HCl dropwise added and stirred for 20 hrs. At room temperature. It creates a water-clear stable sol.
• A4: To a mixture of 27 ml of TEOS, 3 ml of trideca-fluoroctyltriethoxysilane, 120 ml of ethanol are added dropwise to 8 ml of 0.01N HCl and Stirred for 20 hrs. At room temperature. The result is a water-clear stable sol.

2. Preparation of the coating agent (BS):

• Komponente B1 = 10% Al₂(OH)₅Cl × 2–3H₂O in 80% Ethanol B2 = 10% ZrOCl₂ × 8H₂O in 50% Ethanol
• Komponente C1 = Bis-(4-hydroxyphenyl)-sulfon C2 = 1,1,1-Tris-(hydroxymethyl)-propan C3 = Polydimethylsiloxandiol/Hüls AG, 5% in Ethanol C4 = Hydroxypropylcellulose (Klucel H/Aqualon)

By mixing the components listed in Table 1 immediately before coating into a homogeneous sol: Tab. 1: Composition of the coating compositions

• Component B1 = 10% Al ₂ (OH) ₅ Cl x 2-3H ₂ O in 80% ethanol B2 = 10% ZrOCl ₂ x 8H ₂ O in 50% ethanol
• Component C1 = bis (4-hydroxyphenyl) sulfone C2 = 1,1,1-tris (hydroxymethyl) -propane C3 = polydimethylsiloxanediol / Huls AG, 5% in ethanol C4 = hydroxypropylcellulose (Klucel H / Aqualon)

3. Applications of the coating agent

3.1. Coating one polyester fabric

A polyester technical fabric (polyethylene terephthalate) is dip-coated with the coating solutions I and II (two-roll pad, 0.5 m / min roll speed). After drying, 2 × 6 cm ² strips of tensile strength tests are carried out. The strips are stretched in the longitudinal direction until they break.

The maximum tensile force is: untreated 1292 N.
coated with I 1692 N
coated with II 1796 N

3.2. Coating one technical polyamide fabric

One technical polyamide fabric is analogous with the soles II and III 3.3. dip-coated and tested.

The maximum tensile force is: untreated 1170 N
coated with II 1384 N
coated with III 1400 N

Claims (15)

Use of a composition comprising: (A) a layer-forming organosol formed by cohydrolysis of tetraalkoxysilanes Si (OR ¹ ) ₄ , trialkoxysilanes R ² Si (OR ¹ ) ₃ and / or dialkoxysilanes R ³ ₂ Si (OR ¹ ) ₂ , wherein R ¹ and R ^{3 are} alkyl radicals having 1 to 4 carbon atoms and R ^{2 is} an alkyl radical having 1 to 18 C atoms or a fluoroalkyl radical having 1 to 18 C atoms or an epoxy-functionalized alkyl or cycloalkyl radical, in an organic solvent , (B) an aluminum or zirconium halide in an aqueous-organic solvent, and (C) a crosslinking compound having at least 2 hydroxyl groups, for coating textile materials. Use according to claim 1, wherein the solids of the components in the composition in the proportion of 20 parts by weight of A to 1 to 20 parts by weight of B to 1 to 5 parts by weight of C stand. Use according to claim 1 or 2, wherein the component A of the composition by cohydrolysis of 10 parts by weight of a tetraalkoxysilane Si (OR ¹ ) ₄ , 0.1 to 10 parts by weight of one or more trialkoxysilanes R ² Si (OR ¹ ) ₃ and / or 0.1 to 5 parts by weight a dialkoxysilane R ³ ₂ Si (OR ¹ ) _{2 was} formed. Use according to one of the preceding claims, wherein as an organic solvent water-miscible solvents such as low molecular weight alcohols and ketones, cyclic ethers, alkyl glycols or acetonitrile. Use according to one of the preceding claims, wherein Component B of the composition aluminum hydroxide chloride or Zirconium chloride is. Use according to one of the preceding claims, wherein Component C of polyhydroxy compounds such as tris (hydroxymethyl) propane, 2,2-bis (4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, hydroxypropyl cellulose or polydimethylsiloxanediol. Use according to one of the preceding claims, wherein the composition contains nanoparticulate magnetic ferrite particles (γ-Fe ₂ O ₃ ). Use according to one of the preceding claims, wherein the composition alcohol soluble natural resins such as rosin, shellac or copal contains. Use according to one of the preceding claims, wherein the composition contains dyes and / or biocidal compounds. Use of a dye-containing composition according to claim 9 for textile dyes with high color fastness. Use according to any one of the preceding claims Creation of textiles with improved wear properties. Use according to one of the preceding claims Hydrophobization of textiles and improvement of dirt repellent Effect. Process for coating textile materials with the composition defined in claim 1, characterized by the following process steps: (1) Preparation of component A by cohydrolysis of Si (OR ¹ ) ₄ and R ² Si (OR ¹ ) ₃ and / or R ³ ₂ Si (OR ¹ ) ₂ in an organic solvent, (2) adding components B and C dissolved in aqueous alcohol, (3) applying the composition to the material, and (4) drying and curing the layer. The method of claim 13, wherein the drying and Harden without thermal post-curing he follows. A method according to claim 13 or 14, wherein the applying the composition by padding, dipping, spraying, watering or Impregnate he follows.