Process for producing functional vitreous layers

METHOD FOR PRODUCING FUNCTIONAL LAYERS GLASSY

p0002The invention relates to a process for producing functional vitreous, preferably colored or dyed colloid layers on substrates.

p0003In particular, the invention relates to a process for producing functional vitreous layers on substrates, which is characterized in that a composition, which is obtainable by hydrolysis and polycondensation of one

p0004(A) at least one hydrolysable silane of the general formula (I)

p0005SiX, (i:

p0006in which the radicals X are identical or different and are hydrolysable groups or hydroxyl groups, or an oligomer derived therefrom, and

p0007(B) at least one organosilane of the general formula

(II)

p0009^Rla^R2b^SiX(4-ab) dl)

p00101 2 where R is a non-hydrolysable radical, R represents a a functional group-carrying radical, X has the above meaning and a and b have the value 0, 1, 2 or 3, wherein the sum (a + b) has the value 1, 2 or 3, or an oligomer derived therefrom in a molar ratio (a): (B) of 5-50: 50-

p001195, and

p0012(C) gegebenenf lls one or more compounds of glass-forming elements, with at least one function transmitter from the group of temperature resistant dyes and pigments, metal or non-metal oxides, coloring metal ions, metal or metal compound colloids and metal ions which react under reducing conditions to form metal colloids, mixed, the mixed with the function carrier composition to a substrate applies and compresses the coating thermally to form a vitreous layer.

p0013The coating system according to the invention is based on the surprising discovery that the force applied to the substrate composition can be subjected to in spite of their relatively high proportion of organic (carbon-containing) components of a thermal compression at high temperatures without cracking or loss of transparency occurs. It takes a steady transition from an organically modified glass to a purely inorganic (carbon-free) SiO _.- glass instead. The introduced functional carrier, eg Metall¬ colloids, retain their function (light absorption, scattering Licht¬, photochromism, catalysis, etc.) and give example in the case of metal colloids intensely colored vitreous layers. The possibility of the thermal densification at relatively high temperatures allows the production of crack-free coatings with high thermal, mechanical and chemical stability to metal, glass and ceramic surfaces.

p0014The hydrolyzable silanes (A) and the organosilane (B), the hydrolysable groups X, for example, hydrogen or halogen (F, Cl, Br or I), alkoxy (preferably C, _GAlkoxy, such as methoxy, ethoxy, n-propoxy, i-propoxy and butoxy), aryloxy (preferably C_G -.- Aryloxy, such as phenoxy), acyloxy (preferably C₁__GAcyloxy, such as acetoxy or propionyloxy), alkylcarbonyl (preferably C₂_₇Alkylcarbonyl, such as acetyl), amino, monoalkylamino or dialkylamino having preferably 1 to 12, in particular 1 to 6 carbon atoms. 5 atoms.

p0015The nonhydrolyzable radical R is, for example, alkyl

p0016(Preferably C₁__GAlkyl such as methyl, ethyl, n-propyl,

p0017Isopropyl, n-butyl, s-butyl and t-butyl, pentyl, hexyl or cyclohexyl 10), alkenyl (preferably C₂__GAlkenyl, such as

p0018Vinyl, 1-propenyl, 2-propenyl and butenyl), alkynyl (preferably C₂__GAlkynyl such as acetylenyl and

p0019Propargyl) and aryl (preferably C_G_₁₀Aryl, such as

p0020Phenyl and naphthyl). The radicals R and X above may 15 optionally contain one or more customary substituents, such as halogen or alkoxy.

p0021Specific examples of the functional groups of the

p0022Radical R 2 are the epoxy, hydroxyl, ether, ANIMO,

p002320 monoalkylamino, dialkylamino, amide, carboxyl, mercapto, thioether, vinyl, acryloxy, methacryloxy, cyano, halogen, aldehyde, alkylcarbonyl, sulfonic acid and phosphoric acid group. These functional groups are alkylene, alkenylene or arylene bridge groups, which by

p0024__5 Oxygen or sulfur atoms or -NH-groups may be interrupted, bonded to the silicon atom. The bridge groups are derived, for example from the top

p00252 alkyl mentioned, alkenyl or aryl radicals. The radicals R preferably contain from 1 to 18, especially 1 to 8 30 carbon atoms.

p0026«

p0027In the general formula (II) preferably has a value of 0, 1 or 2, b preferably has the value 1 or 2 and the sum (a + b), preferably the value 1 or the second

p002835

p0029Particularly preferred hydrolysable silanes are (A) Tetraalkoxysilanes such as tetraethoxysilane (TEOS). Particularly bevorzgte organosilanes are epoxysilanes such as 3-glycidyloxy propyl trimethoxy silane (GPTS) and aminosilanes such as 3-aminopropyltriethoxysilane and 3- (trimethoxysilyl) - propyl-triethoxysilane (DIAMO).

p0030The molar ratio of the hydrolyzable silane (A) to the organosilane (B) is 5 to 50: 50 to 95, preferably 15 to 25 75 to 85th

p0031The optional component (C) is preferably in the reaction medium-soluble or dispersible. Suitable compounds are, for example (halides, alkoxides, carboxylates, chelates, etc.) of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, boron, aluminum, titanium, zirconium, tin, zinc or vanadium , The hydrolysis and polycondensation is carried out either in the absence of a solvent or preferably in an aqueous or aqueous / organic reaction medium, optionally in the presence of an acidic or basic condensation catalyst such as HC1, or HNO_ NH_ ^. When a liquid reaction medium, the starting components in the reaction medium are soluble. Organic solvents which are particularly suitable water-miscible solvents, such as mono- or polyhydric aliphatic alcohols, ethers, esters, ketones, amides, sulfoxides and sulfones.

p0032Preferably, the hydrolysis and polycondensation under the conditions of the sol-gel process, whereby the

p0033reaction mixture is used in the viscous sol state to coat the substrate.

p0034Optionally, the hydrolysis and polycondensation is carried out in the presence of a complexing agent, for example

p0035Nitrates, beta-dicarbonyl compounds (eg, acetylacetonates or acetoacetates), carboxylic acids (eg Methacrylic acid) or carboxylate (eg acetate, citrate or glycolate), betaines, diols. Diamines (eg DIAMO) 'or crown.

p0036• 5 The sol obtained is and at least one molecular or nanoscale function carrier from the group of temperature resistant dyes and pigments, metal oxides or nonmetal oxides, coloring metal ions, metal or metal compound colloids

p003710 metal ions, which react under reducing conditions to metal colloids, are mixed.

p0038As temperature resistant dyes are, for example azo dyes such as Methyl Orange, Alizarin or Congo red;

p003915 disperse dyes such as Disperse Red; Triphenylmethane dyes such as malachite green, eosin, fluorescein, Aurin and Phenolthalein; Vat dyes such as indigo, thioindigo and anthraquinone dyes; Perylene and fluorescent dyes such as Fluorescent Brightener 28th

p004020 Suitable pigments include phthalocyanines such as Cu, Co, Ni, Zn, or Cr as the central atom; Carbon black pigments with a particle diameter below 500 nm.

p0041Suitable metal or metalloid oxides are, for example Si0,

p0042Ti0₂, Zr0₂, A1₂0₃, -^?^₂° 3 ' ^Cr2 ° 3 ' ^Cu° ' ^Cu2^{0, Zn0}' ^Mn2 ° 3 'SnO ", PdO and In 0_. These metal or non-metal oxides preferably have a particle diameter of 1 to 100 nm.

p004330 The coloring metal ions are preferably in the form of water soluble salts such as nitrates or halides, for example Mn²⁺, Co²⁺, Fe³⁺ or Cr³⁺ used.

p0044As metal colloids in particular those of Ag, 35 are Cu, Au, Pd and Pt. These usually have a Partikel¬ diameter of 1 to 100 nm, that is 1 to 20 nm in Case of transparent layers or 20 to 100 nm in the case of light-scattering layers.

p0045Suitable metal compounds in colloidal form include metal halides such as AgCl, AgBr, AgCl Br. And CuCl,

p0046Metal carbides such as TiC and BC, metal nitrides such as BN and TiN, as Metallarsenide CD_ ^ As_p, Metal phosphides as Cd_P, chalcogenides (sulphides, selenides, tellurides) as AgS, CdS, HgS, PbS and ZnS; CdSe, ZnSe, CdTe; and mixed phases such as ZnSe / PbS₂ and CdS / PbS₂,

p0047The metal compounds have a particle diameter of preferably 1 to 100 nm, especially 1 to 50 nm and particularly preferably 2 to 30 nm.

p0048The amount of the functional carrier is determined by the desired functional properties of the coating, eg the desired color intensity or opacity.

p0049The metal or metal compound colloid can be optionally used in precomplexed form, where, for example, see the above-mentioned complexing agent application.

p0050The blended with the carrier function sol, optionally after the viscosity has been adjusted by removing or adding a solvent still deposited on the substrate by conventional coating methods. Applicable techniques are, for, .B. dipping, casting, spinning, spraying or brushing. The sol produced by this invention has the advantage of a very long pot life compared to conventional TEOS sols. Furthermore, inhomogeneities in the coating (uneven thickness) is less critical to the optical quality of the layer, since in the thermal densification no cracking occurs. Suitable substrates are, for example, those of metals such as stainless steel, copper, brass and aluminum; Glasses such as float glass, borosilicate glass, lead crystal or quartz glass; and ceramics such as Al "0_., Zr0₂, SiO mixed oxides as well as email.

p0051The resulting coating is optionally dried and then densified thermally to form a vitreous layer. This may be at temperatures above 250 ° C, vorzugsweiee above 400 ° C and particularly preferably above 500 ° C to below the

p0052Softening or decomposition point of the substrate occur. The thermal compression may be performed in air or in an inert gas such as nitrogen or argon. The heat treatment can be effected optionally by IR or laser radiation. It is also possible to produce by selective exposure to heat-structured coatings.

p0053The following examples illustrate the invention,

PREPARATION

p0055Producing a GPTS / TEOS Grundsols

p0056Sol synthesis to 160 g of 3-glycidyloxypropyl trimethoxysilane (GPTS), and 40 g of tetraethoxysilane (TEOS) is mixed with 120 ml of ethanol and, with stirring, heated to 60 ° C (molar ratio 80:20). To this mixture 28.5 g of water and 0.5 ml ENT. conc. added and stirred for 15 h at 60 ° C. The sol thus obtained was diluted with 150 ml of ethanol and can be used for several weeks as a coating solution. EXAMPLE 1

p0057Preparation of light-scattering, opalglasähnlichen layer

p0058To the basic 2 g Ti02 powder were placed P25 (Degussa AG) and homogenized for 5 minutes with an ultrasonic disintegrator. With this sol float glass substrates are coated by dipping (pull speed of 2-15 mm / s), and then thermally compressed at 100-500 ° C. An approximately 2 microns thick, matte, light-scattering

p0059Layer shows the same visual impression as opal glass and to a discharge temperature of 500 ° C is free of cracks.

EXAMPLE 2

p0061Producing a pearly layer

p0062-p To the basic 2.5 g Iriodin luster pigment (Merck,

p0063Darmstadt) and 0.1 g Aerosil 300 (Degussa AG) under stirring. The mixture is homogenized for 5 minutes with an ultrasonic disintegrator and then cooled in an ice bath to room temperature. With the coating solution microscope slide by dipping will be with

p0064Drawing speeds of 2-20 mm / s coated and thermally compacted at temperatures between 100 and 500 ° C. After 100 ° C to obtain a flexible, soft coating, while 500 ° C having the coating glass-like hardness. The layers all show a visually attractive pearly.

EXAMPLE 3

p0066Producing a glossy coating on copper The basic sol is applied to s alkaline cleaned copper platelets by dip coating with drawing speeds of 2 to 4 mm / and under argon thermally densified at 200 ° C. The substrates exhibit golden gloss approx 1- 2 micron thick coating.

EXAMPLE 4

p0068Producing a matte coating on stainless steel

p0069The basic sol after the reaction 300 mg Aluox C^R inflicted (Degussa) and the powder with the disintegrator (Branson) 6 min dispersed in the sol. This gives a particle-containing sol on after cooling

p0070RaumLemperatur can be used for coating.

p0071The drawing speeds for coatings on stainless steel 1.4301 (DIN 17440) in the range of 1-4 mm / s. This gives a mat, rough coating on the

p0072Stainless steel sheets, which can be baked without cracking at temperatures of 500-700 ° C. In an inert gas atmosphere (argon), the start-up of stainless steel is prevented. The layer thicknesses are 3-3.5 .mu.m after thermal compression at a rate of 1 K / min.

EXAMPLE 5

p0074Producing a dark brown coating on glass

p0075160 g GPTS, 40 g TEOS, 43.6 g Mn (N0₃) ₂6H₂0 dissolved in 120 ml of ethanol are mixed and heated to 60 ° C. For this purpose, 12 g of water and 0.5 g HN0-. conc. added. The solution is stirred at this temperature for 15 h and then diluted with 150 ml of ethanol sol. Microscope Slides are dipped in the solution and s pulled at drawing speeds of 2-4 mm /. The resulting layers are annealed at 500 ° C and then contain a proportion of 20 wt .-% of Mn0₂, This results in a dark brown color.

p007666.7 g Fe (NO.), · 9H For iron oxide-containing layers₂0 given and after heating to 60 ° C still added 1.7 g of water. is coated and compacted as in the Mn02-containing coatings. There are also dark brown layers with 20 wt .-% Fe₂0₃ receive.

EXAMPLE 6

p0078Producing colored high-temperature resistant layers

p00795 g phthalocyanine are dissolved in 10 ml of ethanol. 10 ml basic sol slowly mixed with the addition of ethanolic dye solution. The resulting sol may be used over a 0.2 micron filter for coating by filtration. The layers are heated at temperatures up to 400 ° C. Is obtained depending on the complex of different colors. For example, copper phthalocyanine provides a blue coating on glass.

EXAMPLE 7

p0081Producing photochromic layers

p0082For the preparation of the sol 10 ml of ethanol and 10 ml basic sol and / or GPTS / TEOS ratios of the prehydrolysate be 0: 1 to 1: 0 were mixed at room temperature.

p0083Then 0.4-2 g AgNO, and 1-20 ml of DIAMO and stirred until complete dissolution. To the clear solution are added 0.003 to 0.8 g K₃_Cu (CN)₄_. For the formation of AgCl in the layers from 0.48 to 12 ml 3-chloropropyl-trimethoxysilane are added to Solansatz. 5

p0084In case silberbromidhaltiger layers _^•.- <__ ■ - dibromoalkanes be used from a chain length of 8 carbon atoms, such as 1, 8-dibromooctane or 1, 10-dibromodecane. For the formation of AgCl Br₁__χ-Mischkristalliten Are both 10 3- chloropropyl-trimethoxysilane and 1, 8-dibromooctane are used (x from 0.25 to 0.75).

p0085After 10-30minütigem stirring the sol is coatable. The coating is applied by immersion. For this purpose, the substrates 15 are immersed in the sol solution, left for 30 s and s pulled at speeds of 1-7.5 mm /.

p0086After 1 hour of drying the films at 65 ° C, these are heated with l-3 ° K / min to 280-350 ° C in normal atmosphere for 20 and 10 minutes to 5 hours heat-treated at the final temperature. The cooling of the layers was carried out in 10 minutes to 10 hours at room temperature.

p0087To investigate the photochromic effect, irradiating __5 the 0.2-1.0 micron thick layers with a 750 W Hg-Xe lamp at a distance of 40 cm from the lamp. This takes place after 1-20 darkening min. The transmission is reduced by 4-45%.

p008830 The dark-colored layers do not regenerate at, room temperature, a brightening is achieved only at temperatures above 100 ° C. The complete discoloration achieved after a heat treatment of 15 minutes to 1 hour at 200 ° C.

p0089The size of the silver halide crystals, which was determined from 35 X-ray measurements, is 5- 25 nm in diameter. EXAMPLE 8

p0090Production of gold, silver, gold / silver, copper, platinum and palladium colloid-containing coatings

p00911. Gold colloid-containing coating on glass substrate

p00920.31 g H [AuCl₄] -2₂0 are dissolved in 4 ml ethanol. To this solution 0.18 g of DIAMO, dissolved in 1 ml of ethanol, added dropwise. The precomplexed in this way gold is then added to 20 ml prehydrolyzed GPTS / TEOS basic, in the previously 1.58 ml of DIAMO were stirred, added dropwise. In this way, any arbitrary Gold stabilizer ratio can be achieved (molar ratio of Au to stabilizer tested to 1:30). The complex mixture is stirred for 30 minutes and then filtered through 1.2 and 0.8 microns filters. Using the sol obtained slides are coated by dipping. The layers are initially slightly yellow. The gold will be reduced at temperatures between 80 ° C and 150 ° C ethanol for colloid. The layer is finally compacted up to 500 ° C under an air atmosphere at temperatures. The layers are transparent and crack-free and, depending on the colloid size red, purple or blue violet.

p00932. Silver colloid-containing coating on glass substrate

p00940.51 g AgN0₃ is dissolved in 3.3 ml of DIAMO and 3 ml of ethanol. The resulting solution is in 20 ml pre-hydrolyzed GPTS / TEOS basic stirred, stirred for 30 minutes and then filtered through 1.2 and 0, 8 micron filter. The resulting light yellow colored sol slides are coated by dipping. The reduction of the silver ions to colloids takes place by heating the layers in ethanol at temperatures up to 500 ° C under

p0095Air atmosphere. The crack-free, transparent layers yellow to yellow-brown.

p00963. Gold / silver colloid-containing coating on glass substrate

p00970.32 g AgN0₃ is dissolved in 2 ml of DIAMO and 2 ml of ethanol and stirred in this mixture in 20 ml of prehydrolyzed GPTS / TEOS basic sol.

p00980.41 g H [AuCl₄-] -2₂0 is dissolved in 4 ml of ethanol and to this solution 0.23 g of DIAMO dissolved in 1 ml ethanol, added dropwise. The resulting solution is stirred into 20 ml of pre-hydrolyzed GPTS / TEOS sol.

p0099Then, the silver-containing sol is added dropwise to the gold-containing sol and stirred for 30 minutes. The complex mixture is stirred for 30 minutes and then filtered through 1.2 and 0.8 microns filters. The layers are initially yellow-orange light. The reduction of the gold and silver ions to form the colloid is effected by ethanol at temperatures between 80 ° C and 140 ° C under an air atmosphere. The transparent

p0100Layers up to 500 ° C are heated without cracking and are aprikosefarben.

p01014. Copper colloid-containing coatings

p01024.1. CuS0₄ as precursor

p01030.4 g CuS0₄ is dissolved in 4 ml of DIAMO and 5 ml of alcohol mixture and stirred for 5 hours. The resulting solution is added to 10 ml prehydrolyzed GPTS / TEOS basic and stirring for a further 30 minutes and then filtered through 1.2 micron filter. Using the sol obtained slides are dip-coated and pre-dried at 80 ° C, the layers are slightly dark blue color. The reduction of the copper to the colloid takes place under forming gas (92% by volume N₂, 8% by volume H₂) at temperatures between 400 ° C and 500 ° C. The crack-free, transparent layers are colored red.

p01044.2. Cu (N0₃)₂ 3H₂0 as precursor 5

p01050.70 g Cu (N0₃)₂ 3H₂0 is dissolved in 5 ml ethanol and 5 ml of DIAMO-ethanol mixture (1 ml DIAMO, 4 ml ethanol) was added. This mixture is stirred into 10 ml of prehydrolyzed GPTS / TEOS basic, stirred for a further 30 minutes

p010610 and then filtered through 1.2 and 0.8 microns filters. Using the sol obtained slides are dip-coated and pre-dried at 80 ° C, the layers are slightly dark blue color. The reduction of the copper to the colloid takes place under forming gas (92% by volume N₂.

p010715 8% volume fraction H₂) At temperatures between 400 ° C and 500 ° C. The crack-free, transparent layers are colored red.

p01085. Platinum colloid-containing coating

p010920

p01100.41 g H₂ [PtCl_G] 2H₂0 is dissolved in 5 ml of ethanol and added dropwise 0.67 ml of DIAMO. The resulting solution is in 20 ml pre-hydrolyzed GPTS / TEOS basic stirred, stirred for a further 30 minutes and then by 3.0 and 1.2 microns

p0111filtered __5 filter. With the sol obtained

p0112Slides coated by dipping and pre-dried at 80 ° C, the layers are a pale yellow color. The reduction of the platinum to the colloid and the curing of the layers is carried out under forming gas (92%

p011330 volume fraction N₂, 8% by volume H₂) At temperatures between 400 ° C and 500 ° C. The crack-free and transparent layers are gefärb drab after tempering.

p011435 6. Palladium colloid-containing coatings on glass and ceramic substrates X mg Pd (ac)₂ or Pd (N0₃)₂ (X = 100-400 g) are dissolved in acetone. To the orange-yellow or brown transparent solution is a mixture of DIAMO and 5 ml of ethanol. The molar ratio of DIAMO and the Pd-precursor may be between 3: 1 varies: 1 and 12. FIG. At the Reak¬ tion mixture 0-50 ml GPTS / TEOS basic are given (depending on the desired concentration of Pd). After the solvent at 30 ° C (100 mbar) for 5 min in a water jet vacuum with the diaphragm pump was distilled off, the sol can be immediately used for coating. After drying the coating (30 min at 80 ° C), the thermal densification of the layer at temperatures up to 600 ° C in N ,, - or Ar atmosphere. In this way, approximately 1 micron thick, transparent and crack-free coatings whose color can be adjusted depending on the Pd concentration between light brown to deep black.