EP1144523A2

EP1144523A2 - Preparations containing fine-particulate inorganic oxides

Info

Publication number: EP1144523A2
Application number: EP99948855A
Authority: EP
Inventors: Juan Gonz Lez-Blanco; Werner Hoheisel; Jens Sicking
Original assignee: Bayer AG
Current assignee: Bayer AG
Priority date: 1998-10-07
Filing date: 1999-09-24
Publication date: 2001-10-17
Also published as: JP2002526630A; CN1411497A; AU6196299A; DE19846096A1; WO2000020519A2; KR20010080059A; WO2000020519A3

Abstract

The invention relates to preparations containing: a) at least one oxide with an average primary particle size ranging from 1 to 100 nm, preferably from 1 to 50 nm; b) at least one dispersing agent with an average molecular weight MW greater than 1000 g/mol; and c) at least one solvent. The inventive preparations are especially suited for producing printing inks which are applied as structured surfaces onto a transparent high-melting substrate using the ink-jet method. Transparent, electrically conductive layers result after sintering under a reducing atmosphere.

Description

Preparations containing fine particulate inorganic oxides

The invention relates to finely particulate inorganic oxide-containing preparations, a process for their preparation, their use for the production of printing inks and the use of the printing inks for the production of transparent, electrically conductive, structured surfaces on transparent carrier materials.

The application of transparent, electrically conductive, structured surfaces (e.g. for display applications), e.g. According to the current state of the art, conductor tracks on insulating, transparent substrates are carried out as follows: After large-area application of a closed layer of the conductive material (eg indium tin oxide) by vapor deposition, sputtering, spray pyrolysis, plasma deposition, immersion processes or CVD processes are also carried out by the the desired structures in semiconductor technology, lithographic processes, for example attached by etching or scratching. The disadvantage of this process is the high level of process engineering involved in producing the structured surfaces.

The object of the present invention is to produce preparations which are transparent, structured surfaces, e.g. can be applied to substrates in the form of conductor tracks with little outlay in terms of process technology.

Furthermore, the object of the present invention is to produce the electrical conductivity within these structured surfaces by sintering in a reducing atmosphere.

It was possible to produce preparations containing fine particulate inorganic oxides and to formulate printing inks from these preparations, which could be applied in a structured manner to transparent substrates using the ink jet process. The structured on the transparent substrates

Areas were subsequently sintered in a reducing atmosphere in electrically conductive structured surfaces can be converted. These electrically conductive structured surface structures (for example conductor tracks) are of particular interest for the electrical industry.

The invention relates to preparations containing a) at least one oxide with an average primary particle size of 1 to 100 nm, b) at least one dispersant with an average molecular weight of M _w greater than 1000 g / mol and c) at least one solvent.

These are preferably preparations containing a) at least one oxide with an average primary particle size of 1 to 100 nm, preferably of 1 to 50 nm, of the type

i) ABX, where

A means Sn, In or Zn and

B is Sb, Sn, F, P, Al or Cd and X is O, S. Se or Te, preferably O and

A forms the host lattice and B represents the dopings in the host lattice, i.e. part of A is substituted by B, the

Substitution of A for B is less than 20 atom%, preferably less than 10 atom%, particularly preferred are the compounds indium tin oxide (A = In,

B = Sn, X = O) and antimony tin oxide (A = Sb, B = Sn, X = O),

ii) tungsten and molybdenum bronzes, the composition Z WO ₃ , or Z _x MoO ₃ with 0 <x <1 and Z being an element of the first and / or second main group of

Periodic table of the elements is iii) tungsten and molybdenum oxides, the composition WO ₃ . _x , or MoO ₃ . _x with x <0.1,

b) at least one dispersant with an average molecular weight M _w of greater than 1,000 g / mol, preferably greater than 1,000 to 500,000 g / mol and c) at least one solvent.

a) Oxides

The oxides a) contained in the preparations according to the invention can be present either in the form of their primary particles, agglomerates or aggregates of primary particles or mixtures of the two. Agglomerates or aggregates are understood to mean particles in which several primary particles interact with one another via van der Waals forces, or in which the primary particles are connected to one another by surface reaction or "sintering" during the production process.

If the oxides a) contained in the preparations according to the invention are in the form of their primary particles, the average primary particle size of the oxides is usually 1 to 100 nm, preferably 1 to 50 nm. It can be determined with the aid of electron micrographs. The primary particles of the oxides preferably have a spherical structure.

If the oxides a) contained in the preparations according to the invention are in the form of their agglomerates or aggregates, the average particle size of these agglomerates or aggregates is less than 500 nm, preferably less than 150 nm. The oxides a) contained in the preparations according to the invention can be crystalline or amorphous, preferably crystalline.

The oxides a) can, for example, by the sol-gel method, chemical vapor reaction method (CVR), chemical vapor condensation method or by

Plasma desorption can be produced.

The oxides a) contained in the preparations according to the invention are preferably present in an amount of from 0.05 to 80% by weight, in particular from 0J to 30% by weight, particularly preferably from 0.5 to 20% by weight, based on the

Preparation, used.

Particularly preferred oxides are indium tin oxide (A = In, B = Sn, X = O) and antimony tin oxide (A = Sb, B = Sn, X = O).

b) dispersant

Molecules with a molecular weight of greater than 1,000 to 500,000 g / mol, preferably greater than 1,000 to 100,000 g / mol and in particular larger, are used as dispersants

Viewed from 1,000 to 10,000 g / mol. The dispersants can be nonionic, anionic, cationic or amphoteric compounds.

Polymeric dispersants are particularly preferred.

The polymeric dispersants are, for example, the compounds mentioned in the directory “Water-Soluble Synthetic Polymers: Properties and Behavior” (Volume I + II, Philip Molyneux, CRC Press, Florida 1983/84). Other polymeric dispersants are, for example, water-soluble and water-emulsifiable compounds, for example homopolymers and copolymers, graft and graft copolymers and statistical block copolymers.

Particularly preferred polymeric dispersants are, for example, AB, BAB and

ABC block copolymers. In the AB or BAB block copolymers, the A segment is a hydrophobic homopolymer or copolymer which, when used in the preparations according to the invention, ensures a connection to the oxide. The B block is a hydrophilic homopolymer or copolymer or a salt thereof which, when used in the preparations according to the invention, ensures the dispersion of the oxide in the solvent in the preparation according to the invention. Such polymeric dispersants and their synthesis are known for example from EP-A-518 225 and EP-A-556 649.

Examples of suitable polymeric dispersants are:

Polyethylene oxides, polypropylene oxides, polyoxymethylenes, polytrimethylene oxides, polyvinyl methyl ethers, polyethyleneimines, polyacrylic acids, polyarylamides, polymethacrylic acids, polymethacrylamides, poly-N, N-dimethylacrylamides, poly-N-isopropylacrylamides, poly-N-acrylglycinamides, poly-N-methacrylacrylglycinamides, poly Copolymers of polyvinyl alcohol and

Polyvinyl acetates, polyvinyl pyrrolidone, polyvinyl oxazolidones, polyvinyl methyl oxazolidones.

Examples of suitable natural polymeric dispersants are: cellulose, starch, gelatin or their derivatives.

Examples of nonionic dispersants are: alkoxylates, alkylolamides, esters, amine oxides, silanes such as 3-glycidyloxypropyltrimethoxysilane and alkylpolyglycosides. Other suitable nonionic dispersants are: reaction products of alkylene oxides with alkoxylatable compounds, such as, for example, fatty alcohols, fatty amines, fatty acids, phenols, alkylphenols, arylalkylphenols, such as styrene-phenol condensates, carboxamides and resin acids. These reaction products are preferably ethylene oxide

Adducts resulting from the reaction of ethylene oxide with

1) saturated and / or unsaturated fatty alcohols with 6 to 20 carbon atoms or

2) alkylphenols with 4 to 12 carbon atoms in the alkyl radical or 3) saturated and / or unsaturated fatty amines with 14 to 20 carbon atoms or

4) saturated and / or unsaturated fatty acids with 14 to 20 carbon atoms or

5) hydrogenated and / or unhydrogenated resin acids emerge.

Suitable ethylene oxide adducts are, in particular, the alkoxylable compounds mentioned under 1) to 5) with 5 to 120, preferably 5 to 60, in particular 5 to 30, ethylene oxide units per molecule.

Nonionic polymeric dispersants such as, for example, polyethylene oxides, polypropylene oxides, polyoxymethylenes, polytrimethylene oxides, polyvinyl methyl ether, polyethyleneimines, polyacrylic acids are particularly preferred.

Polyarylamides, polymethacrylic acids, polymethacrylamides, poly-N, N-dimethylacrylamides, poly-N-isopropylacrylamides, poly-N-acrylglycinamides, poly-N-methacrylglycinamides, polyvinyl alcohols, polyvinyl pyrrolidone, polyvinyl oxazolidones, polyvinylmethyloxazolidones.

Examples of anionic dispersants are: alkyl sulfates, ether sulfates, ether carboxylates, phosphate esters, sulfosuccinates, sulfosuccinatamides, paraffin sulfonates, olefin sulfonates, sarcosinates, isothionates, taurates and lignin compounds. Anionic, polymeric dispersants are particularly preferred.

Preferred anionic polymeric dispersants are condensation products of aromatic sulfonic acids with formaldehyde, such as, for example, condensation products from formaldehyde and alkylnaphthalenesulfonic acids, condensation products from formaldehyde and naphthalenesulfonic acids and / or benzenesulfonic acids or condensation products from optionally substituted phenol with formaldehyde and sodium bisulfite.

Preference is also given to condensation products which are obtained by reacting

Naphthols with alkanols, addition of alkylene oxide and at least partial conversion of the terminal hydroxy groups into sulfo groups or half esters of maleic acid, phthalic acid or succinic acid are available.

Furthermore, preferred anionic dispersants are compounds from the

Group of sulfosuccinic acid esters, alkylbenzenesulfonates, sulfated alkoxylated fatty acid alcohols or their salts can be used. Alkoxylated fatty acid alcohols are understood to mean in particular those with 5 to 120, preferably 5 to 60, in particular 5 to 30, ethylene oxide units per molecule of C ₆ -C ₂₂ fatty acid alcohols which are saturated or unsaturated, in particular stearyl alcohol. A stearyl alcohol alkoxylated with 8 to 10 ethylene oxide units is particularly preferred. The sulfated alkoxylated fatty acid alcohols are preferably present as a salt, in particular as an alkali or ammonium salt, preferably as a diethylammonium salt.

Further examples of preferred anionic, polymeric dispersants are the salts of polyacrylic acids, polyethylene sulfonic acids, polystyrene sulfonic acid, polymethacrylic acids, polyphosphoric acids and polyaspartic acids.

Also preferred are anionic, polymeric dispersants which are copolymers of acrylic monomers. These copolymers are exemplified by Combinations of the following monomers are available, which are synthesized to random or alternating copolymers or graft copolymers:

Acrylamide, acrylic acid;

Acrylamide, acrylonitrile;

Acrylic acid, N-acrylglycinamide;

Acrylic acid, ethyl acrylate;

Acrylic acid, methyl acrylate;

Acrylic acid, methylene butyrolactam;

N-acrylglycinamide, N-isopropylacrylamide;

Methacrylamide, methacrylic acid;

Methacrylic acid, benzyl methacrylate;

Methacrylic acid, diphenylmethyl methacrylate;

Methacrylic acid, methyl methacrylate;

Methacrylic acid, styrene.

Further preferred inorganic dispersants are lignin sulfonates, for example those obtained by the sulfite or kraft process (sulfite and kraft lignin sulfonates). These are preferably products which are partially hydrolyzed, oxidized, propoxylated, sulfonated, sulfomethylated or disulfonated and are fractionated by known processes, for example by the molecular weight or by the degree of sulfonation. Mixtures of sulfite and kraft lignin sulfonates are also suitable. Lignin sulfonates with an average molecular weight of greater than 1,000 to 100,000 g / mol, a content of active lignin sulfonate of at least 80% and preferably with a low content of polyvalent cations are particularly suitable. The degree of sulfonation can vary within wide limits. Examples of cationic dispersants are: alkylammonium compounds and imidazoles.

Cationic, polymeric dispersants are particularly preferred.

Examples of cationic, polymeric dispersants are the salts of polyethyleneimines, polyvinylamines, poly (2-vinylpyridines), poly (4-vinylpyridines), poly (diallyldimethylammonium) chloride, poly (4-vinylbenzyltrimethylammonium) salts, poly (2- vinylpiperidine) and polylysine.

Examples of amphoteric dispersants are: betaines, glycinates, propionates and imidazolines.

Anionic and cationic polymers are summarized as polyelectrolytes and can be partially or completely dissociated in an aqueous and / or organic phase.

The dispersants used are preferably in an amount of 0J to 200% by weight, in particular 0.5 to 100% by weight, particularly preferably 1 to

20 wt .-%, based on the amount of oxides used.

Preparations containing are particularly preferred

a) at least one oxide with an average primary particle size of 1 to 100 nm, preferably of 1 to 50 nm of the type

i) ABX, where A is Sn, In or Zn and

B means Sb, Sn, F, P, AI or Cd and XO, S, Se or Te, preferably O, and A forms the host lattice and B represents the dopings in the host lattice, ie part of A is substituted by B, the substitution of A for B being less than 20 atom%, preferably less than Is 10 atom%, particularly preferred are the compounds indium tin oxide (A = In, B = Sn, X = O) and antimony tin oxide (A = Sb, B = Sn, X = O),

ii) tungsten and molybdenum bronzes, the composition Z _x WO ₃ or Z _x MoO 3 with 0 <x <1 and Z being an element of the first and / or second main group of the periodic table of the elements,

iii) Tungsten and molybdenum oxides, the composition WO ₃ _ _x , or MoO ₃ . _x with x <0.1,

b) at least one dispersant with an average molecular weight (M _w ) of greater than 1,000 g / mol, preferably with M _w greater than 1,000 to 500,000 g / mol, selected from the group of anionic dispersants:

Sulfosuccinic acid esters, alkylbenzene sulfonates, sulfated, alkoxylated fatty acid alcohols or their salts, ether sulfates, ether carboxylates, phosphate esters, sulfosuccinatamides, paraffin sulfonates, olefin sulfonates, sarcosinates, isothionates, taurates, lignin compounds, condensation products with formaldehyde acids, from aromatic sulfonates, from aromatic sulfonates, from aromatic sulfonates Condensation products from formaldehyde and naphthalenesulfonic acids and / or benzenesulfonic acids or

Condensation products from optionally substituted phenol with formaldehyde and sodium bisulfite, condensation products of naphthols with alkanols, addition of alkylene oxide and at least partially Conversion of the terminal hydroxyl groups into sulfo groups or half esters of maleic acid, phthalic acid or succinic acid are available, as well as polymers of amino acid units, in particular polyaspartic acid, or

from the group of the cationic dispersants: quaternary alkylammonium compounds and imidazoles, or

from the group of amphoteric dispersants: glycinates, propionates and imidazolines, or

from the group of nonionic dispersants:

Alkoxylates, alkylolamides, esters, amine oxides, silanes such as, for example, 3-glycidyloxypropyltrimethoxysilane, alkylpolyglycosides and reaction products of alkylene oxides with alkoxylable compounds, such as, for example, fatty alcohols, fatty amines, fatty acids, phenols, alkylphenols,

Arylalkylphenols, such as styrene-phenol condensates, carboxamides and resin acids, preferably ethylene oxide adducts, which result from the reaction of ethylene oxide with

1) saturated and / or unsaturated fatty alcohols with 6 to 20 carbon atoms or

2) alkylphenols with 4 to 12 carbon atoms in the alkyl radical or

3) saturated and / or unsaturated fatty amines with 14 to 20 carbon atoms or

4) saturated and / or unsaturated fatty acids with 14 to 20 C atoms or 5) hydrogenated and / or unhydrogenated resin acids, particularly preferably ethylene oxide adducts of the alkoxylable compounds mentioned under 1) to 5) with 5 to 120, preferably 5 to 60, in particular 5 to 30, ethylene oxide units per molecule.

c) at least one solvent. c) solvent

The solvents used in the inventive preparations c) are preferably water, ahphatische C, -C ₄ alcohols such as methanol, ethanol, isopropanol, n-propanol, ahphatische n-butanol, isobutanol or tert-butanol,

Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone or diacetone alcohol,

Polyols such as ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, trimethylolpropane, polyethylene glycol with an average molecular weight of 100 to 4,000 g / mol, preferably 400 to 1,500 g / mol, glycerol, monohydroxy ether, preferably monohydroxyalkyl ether are particularly preferred

Mono-C, -C ₄ -alkyl glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monoethyl ether, thiodiglycol, triethylene glycol monomethyl ether or triethylene glycol pyrrolidone-2-methylrolidone-nolonyl ether, methyl-2-pyrrolidone -pyrrolidone, 1.3-

Dimethylimidazolidone, dimethylacetamide and dimethylformamide.

Mixtures of solvents are preferably used, particularly preferably mixtures of polyethylene glycol / 2-pyrrolidone / water or polyethylene glycol / 2-pyrrolidone / ethanol.

The amount of the solvent used in the preparations according to the invention is preferably 10 to 99% by weight, particularly preferably 30 to 98% by weight, based on the solids content of oxide in the preparation according to the invention.

In addition to the components a) -c) used, the preparations according to the invention may contain further cationic anionic, amophotere and / or nonionic surface-active compounds, for example those which are available in the directory "Surfactants Europe, A Directory of Surface Active Agents Europe "(Edited by Gordon L. Hollis, Royal Society of Chemistry), Cambridge (1995).

If the dispersant b) used in the preparations according to the invention contains ionic groups, these surface-active compounds should preferably be non-ionic or of the same ionicity as the dispersant b).

The preparations according to the invention can furthermore contain additives in addition to the components a) -c) used.

Preferred additives are aromatic dicarboxylic acids and their esters.

Preferred aromatic dicarboxylic acids are phthalic acid, isophthalic acid and terephthalic acid. Preferred esters are isophthalic diesters, phthalic diesters and

Terephthalic acid diester of the formula RCOO-C ₆ H ₄ -COOR ', where R, R' independently of one another are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, phenyl or benzyl.

Diethyl phthalate is particularly preferred. Mixtures of the additives mentioned are also suitable.

Further preferred additives are compounds from the group of terpenes, terpenoids, fatty acids and fatty acid esters.

Preferred compounds are ocimen, myrcene, geraniol, nerol, linalool, citronellol, geranial, citronellal, neral, limonene, menthol, for example (-) - menthol, menthone or bicyclic monoterpenes, saturated and unsaturated fatty acids with 6 to 22 carbon atoms, for example Stearic acid, oleic acid, linoleic acid or linolenic acid. Mixtures of the additives mentioned also come in

Question. The preparation of the preparations according to the invention comprises wet comminution and a dilution step.

The wet comminution optionally includes a pre-comminution, the production of a grinding suspension and the grinding.

To prepare the grinding suspension, the oxides a), if appropriate after comminution, are generally in powder form or in the form of water-moist

Press cake together with a portion of the dispersant and polar organic solvent and / or water, preferably deionized water, are beaten to a homogeneous grinding suspension, i.e. introduced and homogenized. The dispersants used adsorb to the oxides, which thereby deagglomerate or deaggregate. This grinding suspension can be produced, for example, by means of a stirrer, dissolver and similar devices.

The grinding suspension can also contain fractions of low-boiling solvents (boiling point <150 ° C), which are removed in the course of the subsequent fine grinding

Evaporation can be carried out. However, it can also contain proportions of higher-boiling solvents, surface-active compounds as mentioned above or other additives e.g. Grinding aids, defoaming agents or wetting agents.

The solids content of oxide a) in the grinding suspension is preferably above the desired solids content in the finished preparation. The desired solids content in the finished preparation is preferably set after the wet comminution. The grinding takes place to the desired particle size distribution. The grinding is carried out, for example, in kneaders, roller mills, kneading screws, ball mills, rotor-stator mills, dissolvers, corundum disc mills or vibrating mills. Milling is preferably carried out in high-speed, continuously or discontinuously charged stirred ball mills

Grinding bodies with a diameter of 0J to 5 mm. The grinding media can be made of glass, ceramic or metal, e.g. Be steel. The grinding temperature is preferably in the range from 0 to 250 ° C., but as a rule at room temperature, particularly preferably below the cloud point of the dispersant b) used.

In a likewise preferred procedure, the grinding can be carried out partially or completely in a high-pressure homogenizer or in a so-called jet disperser (known from DE-A 19 536 845). As a result, the content of grinding media abrasion in the suspension or the release of soluble substances from the

Grinding bodies (e.g. ions from vitreous bodies) reduced to a minimum or completely avoided. In addition, the formation of foam can be prevented and possible reagglomeration avoided.

In a dilution step, the suspension obtained after grinding is mixed and homogenized in a manner known per se in solvent, preferably water, optionally with the remaining amounts of dispersant and, if appropriate, further additives, and adjusted to the desired solids content of the finished preparation. If necessary, dispersants can also be added here, for example in order to avoid reagglomeration of fine particles in the finished preparation.

Of particular advantage is a process for the preparation of the preparations according to the invention, in which in the grinding step for the preparation of the grinding suspension for the

Stabilization sufficient dispersants are provided. in the Following this or after the dilution step, dispersing agents and / or excess surface-active compounds which are not adsorbed on the oxides a) used are preferably removed and then the desired solids content in the finished preparation is adjusted.

One method for removing dispersants in solution is, for example, centrifuging the grinding suspension and then decanting off the supernatant. Membrane or microfiltration processes can also be considered.

The preparations according to the invention are preferred for applying structured, conductive and transparent surfaces (for example for display applications), such as Conductor tracks are used on insulating, transparent substrates. The preparations according to the invention can be applied to the substrates in the form of pastes or pourable compositions by knife coating or casting or in the form of printing inks by inkjet printing.

The preparations according to the invention are preferably applied to substrates in the form of printing inks by ink-jet printing.

The invention further relates to printing inks containing the preparations according to the invention.

In addition to the preparations according to the invention, the printing inks according to the invention can contain agents for adjusting the viscosity of the ink, such as, for example, polyvinyl alcohol, polyvinylpyrrolidone, methyl cellulose and others, agents known to the person skilled in the art, provided that they do not adversely affect the stability of the printing ink, the printing behavior and the drying behavior on a suitable surface. The printing inks according to the invention can also contain preservatives, surfactants and pH regulators.

Preferably methyl-isothiazolin-3-one,

Chloromethyl-isothiazolin-3-one, benzisothiazolin-3-one or mixtures thereof.

NaOH, ammonia, aminomethylpropanol N, N-dimethylaminoethanol are preferably used as pH regulators.

The printing inks according to the invention can be produced analogously to the production of the preparations according to the invention, the printing ink according to the invention being adjusted to the desired viscosity, density and

Surface tension is preferably carried out with the adjustment of the solids content of the printing ink according to the invention.

The physical ink properties are preferably adjusted for use in conventional inkjet printers, with the surface tension preferably

20 to 70 mN / m and the viscosity should preferably be less than 20 mPa-s, preferably 0.5 to 10 mPa-s.

The printing inks according to the invention are preferably filtered before use, for example using 0.5 to 5 μm membrane or glass filters.

The printing inks according to the invention show excellent dispersion and

Storage stability over a wide temperature range. It occurs at her

Use in ink-jet printers to prevent blockages in print heads (so-called kogation or clogging). The prints on different transparent Substrates such as glass or heat-resistant plastics show high water and

Migration fastness.

The invention further relates to a method for producing electrically conductive, structured, transparent surfaces (for example for display applications), such as Conductor tracks on insulating, transparent

Substrates such as glass or high-melting plastics by applying the printing inks according to the invention in the form of structured, transparent surfaces by ink-jet printing and then converting these structured, transparent surfaces into electrically conductive, structured transparent surfaces by sintering the printed substrates in reductive

The atmosphere.

Ink-jet printing or the ink-jet method is known per se. Generally, the printing ink is filled into a receptacle of an ink jet printhead and sprayed onto the substrate in small droplets. The ink ejection in droplets is preferably carried out via a piezoelectric crystal, a heated cannula (bubble or thermo-jet process) or mechanical pressure increase, pressure being exerted on the ink system and ink drops being thrown out in this way. The droplets are shot from one or more small nozzles onto the substrate.

A method is also possible in which the smallest volumes, in the form of drops, are brought onto a substrate by means of electrostatic deflection from an ink jet.

The individual droplets on the substrate are combined into characters or graphic patterns such as structured surfaces by electronic control.

After the printing ink has been applied, the process according to the invention is used

Sintering step, wherein the printed substrate in a reducing atmosphere (e.g. Argon-hydrogen gas mixture), preferably under forming gas (= 5% hydrogen, 95% argon) at temperatures of 150 to 600 ° C. Subsequent sintering in air at 400 to 600 ° C. is preferably carried out in order to remove organic constituents without residue.

The electrically conductive, structured, transparent surfaces produced by the method according to the invention have a specific resistance of 0.014 to 0.11 ohm * cm.

Examples

example 1

2.5 g of polyaspartic acid (molecular weight 3,000 g / mol) were deionized in 247.5 ml

Water dissolved. 50 g of solid indium tin oxide powder (produced by the CVR method with a primary particle size of 2 to 30 nm, determined by means of TEM) were added to this solution with thorough mixing (magnetic stirrer). This suspension was predispersed for 5 minutes with an ultrasound finger (power: 200 watts). The mixture was then heated under reflux for 5 hours (patio heater).

The cooled suspension was sucked off through a round filter with a pore size of 0J2 μm (= type HAWP ^® from Millipore) in a glass frit and the residue was washed with water. The residue was then dried in a drying cabinet at 70 ° C. for 12 hours.

5 g of the dry, modified indium tin oxide powder were taken up in 100 ml of a solvent mixture of 16% PEG 1000 (= polyethylene glycol M _w = 1 000 g / mol) and 8% 2-pyrrolidone in water and the pH was half-concentrated Ammonia solution adjusted to pH = 6. This was followed by a 5-minute treatment with an ultrasound finger. For the particle characterization of the preparation, an aliquot was diluted with the above-mentioned solvent mixture and the average particle diameter of the indium tin oxide particles was determined by the dynamic light scattering method (scattered light distribution). A particle diameter of 91 nm could be measured. The mass distribution was determined in the ultracentrifuge:

Here d ₁₀ means that 10% of all particles are not larger than 17 nm, d ₅₀ means that 50% of all particles are not larger than 43 nm and d ₉₀ means that 90% of all particles are not larger than 87 nm. In this context, particles are to be understood as primary particles as well as aggregates or agglomerates.

Example 2

2.5 g of polyaspartic acid (molecular weight 3,000 g / mol) were dissolved in 247.5 ml of water. 50 g of solid indium tin oxide powder (produced by the CVR method with a primary particle size of 2 to 30 nm, determined by means of TEM) were added to this solution with thorough mixing (magnetic stirrer). This suspension was heated under reflux for 5 hours (patio heater). The cooled suspension was passed through a round filter with a pore size of 0.22 μm (= type HAWP ^® der

Millipore) sucked off in a glass frit. The residue was washed with water and then dried in a drying cabinet at 70 ° C. for 12 hours.

5 g of the dry, modified indium tin oxide powder were mixed with (magnetic stirrer) in 100 ml of a solvent mixture of 10% PEG

1000 (= polyethylene glycol M _w = 1000 g / mol), 5% 2-pyrrolidone and 35% diethyl phthalate in ethanol. This was followed by a two-minute treatment with an ultrasound finger. For the particle characterization of the preparation, an aliquot was diluted with the above-mentioned solvent mixture and the average particle diameter of the indium tin oxide particles was determined by the dynamic light scattering method (scattered light distribution). A particle diameter of 91 nm could be measured. The mass distribution was determined in the ultracentrifuge:

Here d ₁₀ means that 10% of all particles are not larger than 34 nm, d ₅₀ means that 50% of all particles are not larger than 79 nm and d ₉₀ means that 90% of all

Particles that are not larger than 107 nm. In this context, particles are to be understood as primary particles as well as aggregates or agglomerates.

Example 3

2.5 g of polyacrylic acid (molecular weight 25,000 g / mol) were dissolved in 247.5 ml of deionized water. 50 g of solid indium tin oxide powder (produced by the CVR method with a primary particle size of 2 to 30 nm, determined by means of TEM) were added to this solution with thorough mixing (magnetic stirrer). This suspension was predispersed for 5 minutes with an ultrasound finger (power: 200 watts). The mixture was then heated under reflux for 5 hours (patio heater). The cooled suspension was sucked off with a glass frit through a round filter with a pore size of 0J2 μm (= type HAWP ^® from Millipore) and the residue was washed with water. The residue was then dried in a drying cabinet at 70 ° C. for 12 hours.

5 g of the dry, modified indium tin oxide powder were in 100 ml of a solvent mixture of 16% PEG 1000 (= polyethylene glycol M _w = 1 000 g / mol) and 8% 2-pyrrolidone taken up in water and the pH adjusted to pH = 6 with half-concentrated ammonia solution. This was followed by a 5-minute treatment with an ultrasound finger.

For the particle characterization of the preparation, an aliquot was diluted with the above-mentioned solvent mixture and the average particle diameter of the indium tin oxide particles was determined by the dynamic light scattering method (scattered light distribution). A particle diameter of 91 nm could be measured. The mass distribution was determined in the ultracentrifuge:

Here, d, ₀ means that 10% of all particles are not larger than 23 nm, d ₅₀ means that 50% of all particles are not larger than 60 nm and d ₉₀ means that 90% of all particles are not larger than 92 nm. In this context, particles are to be understood as primary particles as well as aggregates or agglomerates.

Example 4

2.5 g of polyacrylic acid (molecular weight 25,000 g / mol) were dissolved in 247.5 ml of water. To this solution, 50 g of solid indium tin oxide powder (prepared according to the

CVR method with a primary particle size of 2 to 30 nm, determined by means of TEM) with mixing (magnetic stirrer) added. This suspension was heated under reflux for 5 hours (patio heater). The cooled suspension was sucked off through a round filter with a pore size of 0.22 μm (= type HAWP ^® from Millipore) in a glass frit. The residue was washed with water and then dried in a drying cabinet at 70 ° C. for 12 hours. 5 g of the dry, modified indium tin oxide powder were mixed in (magnetic stirrer) in 100 ml of a solvent mixture of 10% PEG 1000 (= polyethylene glycol M _w = 1000 g / mol), 5% 2-pyrrolidone and 35% diethyl phthalate in Ethanol added. This was followed by a 2 minute treatment with an ultrasound finger.

Here d ₁₀ means that 10% of all particles are not larger than 34 nm, d ₅₀ means that 50% of all particles are not larger than 67 nm and d ₉₀ means that 90% of all

Particles are not larger than 1 10 nm. In this context, particles are to be understood as primary particles as well as aggregates or agglomerates.

Example 5

2.5 g of 3-glycidyloxypropyltrimethoxysilane was dissolved in 497.5 g of ethanol. 50 g of solid indium tin oxide powder (produced by the CVR method with a primary particle size of 2 to 30 nm, determined by means of TEM) and 3 ml of 1 molar hydrochloric acid were mixed with this solution (magnetic stirrer) to this solution. This suspension was heated under reflux for 5 hours (patio heater). The cooled suspension was sucked off through a round filter with a pore size of 0.22 μm (- type HAWP ^® from Millipore) in a glass frit. The residue was washed with ethanol and then dried in a drying cabinet at 70 ° C. for 12 hours.

5 g of the dry, modified powder were mixed with (magnetic stirrer) in 100 ml of a solvent mixture of 10% PEG 1000

(= Polyethylene glycol M _w = 1 000 g / mol, 5% 2-pyrrolidone and 35% diethyl phthalate in ethanol.

For particle characterization of the preparation, an aliquot was diluted with the above-mentioned solvent mixture and the mean particle diameter of the

Indium tin oxide particles determined by the method of dynamic light scattering (scattered light distribution). A particle diameter of 91 nm could be measured. The mass distribution was determined in the ultracentrifuge:

Here d ₁₀ means that 10% of all particles are not larger than 31 nm, d ₅₀ means that 50% of all particles are not larger than 64 nm and cL ,,, means that 90% of all particles are not larger than 117 nm . In this context, particles are to be understood as primary particles as well as aggregates or agglomerates.

Example 6

The preparations prepared in Examples 1 to 5 were used as printing inks. Structured areas and conductor tracks were printed on 1 to 2 mm thick glass plates using an ink jet printer.

The glass plates printed in this way were sintered for 6 hours under forming gas (5% hydrogen, 95% argon) at 400 ° C. and then in an oven sintered in air for 6 hours at 400 ° C. The electrically conductive, structured surfaces produced in this way are transparent and have a specific resistance of 0.014 to OJ 1 ohm * cm.

Claims

claims

1. Preparations containing a) at least one oxide with an average primary particle size of 1 to 100 nm, b) at least one dispersant with an average molecular weight M _w of greater than 1000 g / mol, c) at least one solvent.

2. Preparations according to claim 1, containing a) at least one oxide with an average primary particle size of 1 to 100 nm of the type

i) ABX, where A is Sn, In or Zn and

B means Sb, Sn, F, P, AI or Cd and

X is O, S, Se or Te, preferably O and

A forms the host lattice and B represents the doping in the host lattice, i.e. a part of A is substituted by B, the substitution of A by B being less than 20 atomic%, preferably less than 10 atomic% and / or,

ii) tungsten and molybdenum bronzes, the composition Z _x WO ₃ , or Z _x MoO ₃ with 0 <x <1 and Z being an element of the first and / or second main group of

Periodic table of the elements is, and / or

iii) tungsten and molybdenum oxides, the composition WO ₃ . _x , or MoO ₃ . _x with x <0.1, b) at least one dispersant with an average molecular weight M _w of greater than 1,000 g / mol, c) at least one solvent.

3. Preparation according to claim 1 and 2, wherein the oxide indium tin oxide

(A = In, B = - Sn, X = O) or antimony tin oxide (A = Sb, B = Sn, X = O).

4. Preparations according to one or more of the preceding claims 1 to 3, characterized in that they contain 0.05 to 80 wt .-%, at least one oxide a), based on the preparation and

0J to 200 wt .-%, at least one dispersant b), based on the amount of oxide used, and

10 to 98 wt .-%, at least one solvent c), based on the preparation.

5. Preparations according to one or more of the preceding claims 1 to 4, characterized in that the oxides a) are present as primary particles, agglomerate, aggregate and / or as a mixture thereof, the agglomerates and aggregates having an average particle size of less than

500 nm, preferably less than 150 nm.

6. Preparations according to one or more of the preceding claims 1 to 5, characterized in that polymeric dispersants are used as the dispersant b).

7. Preparation according to one or more of the preceding claims 1 to 6, characterized in that the preparations additionally contain cationic, anionic, amphoteric and / or nonionic surface-active compounds, in particular aromatic dicarboxylic acids or their

Diester.

8. A process for the preparation of preparations according to one or more of the preceding claims 1 to 7, consisting of the steps of preparing a grinding suspension, grinding and dilution, wherein a preliminary comminution is optionally carried out before the preparation of the grinding suspension.

9. Use of the preparations according to claims 1 to 7 for the production of printing inks.

10. Printing inks containing preparations according to claim 1 to 6

1 1. Printing inks according to claim 9, characterized in that they contain pH regulators and / or surfactants and / or preservatives.

12. Process for the production of electrically conductive, structured surfaces

Substrates by applying printing inks according to claims 9 and 10 in the form of structured surfaces by ink-jet printing and subsequent conversion of these structured surfaces into electrically conductive, structured surfaces by sintering the printed substrates in a reductive atmosphere at temperatures of 150 to 600 ° C.

13. Printed substrates with printing inks according to claim 9 and 10.