WO2002061029A2

WO2002061029A2 - Method, substance and object

Info

Publication number: WO2002061029A2
Application number: PCT/EP2002/000952
Authority: WO
Inventors: Rüdiger Nass; Gerhard Jonschker
Original assignee: Nanogate Technologies Gmbh
Priority date: 2001-01-30
Filing date: 2002-01-30
Publication date: 2002-08-08
Also published as: AU2002242699A1; JP2004528404A; WO2002061029A3; CH696236A5

Abstract

The invention relates to a composition for producing a surfactant having combined cleaning and impregnating properties, containing a long-chained non-fluorinated silane and a perfluorinated silane. According to the invention, a linear cross-linked polysiloxane network is formed by the oligomer/polymer formed from the two silane compounds by hydrolysis and condensation, comprising free reaction points enabling three-dimensional cross-linking.

Description

Title: Process, substance and subject

description

The present invention relates to the preamble and thus to compositions, processes for their use and objects which are modified with the compositions and / or to the described procedure. The invention is generally concerned with dirt-repellent and / or other modified surfaces and / or their production, in particular in machines and machine parts for the printing industry.

Numerous compositions, mostly for use as coatings, are already known which are based on organically modified inorganic polycondensates, in particular those on Si, Al, Ti and Zr.

For example, DE-A-38 36 815 discloses a method and a composition for producing scratch-resistant materials, in particular coatings with improved elasticity and adhesion. For this purpose, a composition of a polycondensate obtained by hydrolytic polycondensation of at least one inorganic compound and at least one polyfunctional organic compound with activatable functional groups is applied to a substrate, after which it is hardened and e.g. the functional groups of the organic compound are activated by heating.

BESTATIGUNGSKOPIE EP-B-0 587 667 describes coating compositions based on polycondensates of one or more hydrolyzable compounds of elements M of the main groups III to. V and the subgroups II to IV of the periodic table, wherein at least some of these compounds in addition to hydrolysable groups A also comprises non-hydrolyzable, carbon-containing groups B and the total molar ratio of groups A to groups B in the zugrundelie- ^{'constricting} monomeric starting compounds 10: 1 to 1: 2, with 0.1 to 100 mol% of groups B being groups B 'which have an average of 5 to 30 fluorine atoms which are bonded to one or more aliphatic carbon atoms which are separated from M by at least two atoms ,

Although these methods lead to results that are related to many properties, e.g. Scratch resistance and transparency deliver very satisfactory results, these compositions are still in need of improvement for a number of applications. So it is often desirable not only to modify an object on its surface, but also to clean it.

The aim of the present invention is to provide something new for commercial use. According to one aspect of the present invention, in particular compositions and methods for their production are to be provided which have improved properties compared to those of the prior art. The invention therefore relates first of all to a silane compound in a cleaning fluid and in this case cleaning substances are in particular those substances which are capable of swelling dirt which is capable of swelling, in general in particular organic solvents, in particular volatile solvents (for example cleaning gasoline, ethyl acetate, ester, Ketones, etc.), while highly fluorinated silanes are suitable as silanes. Long-chain highly fluorinated silanes in monomeric, oligomeric or polymeric form are preferred, where long-chain highly fluorinated means here that at least five C atoms, each of which has at least one fluorine atom but which are preferably fully fluorinated, are present on a monomer; In the case of oligomeric or polymeric silanes, it has proven to be sufficient if an amount around or below 1% active substance content, preferably below 200 ppm active substance content, is used, and the correspondingly low active substance contents are likewise preferred for monomers.

Such cleaning agents have a high cleaning power especially against stubborn dirt such as

Ink residues on printing presses or parts thereof, such as anilox rollers or the like. It is not yet fully understood why the composition described gives particularly good results in its preferred forms. It is assumed, however, that dirt is initially swelled, thereby "in first ^" _. hardened dirt particles form capillaries, entering cleaning fluid with the perfluorinated silanes in this quasi creeping and then through the 'hydrophobicizing and / or oleophobicizing the ^Kapill' aro- berflachen further penetration of the fluids easier. In a variant of the invention, a polyester / oligomeric silane is used, which can simultaneously serve as a surfactant and impregnating agent for surfaces in special cleaning systems. It is built up from a polysiloxane network, which is preferably linearly networked and contains further locations capable of three-dimensional networking. The polymer is characterized in particular by the fact that the organic side chains which are bonded to the silicon atom have a certain functionality and occur in a special relationship to one another.

For example, a polymer was produced from a fluoroalkyltriethoxysilane and an octyltriethoxysilane, which is soluble in suitable organic solvents (eg cleaning gasoline, ethyl acetate, esters, ketones, etc.) and is characterized by a very special cleaning power. This can be determined in particular if this surfactant is dissolved in cleaning gasoline, which is used in the printing industry. If necessary, suitable co-solvents can also be used to dissolve the polymer (eg ethyl acetate with cleaning petrol). Bringt- _^ is now the offset with the surfactant cleaning gasoline contaminated metal parts and lets it react for some time, one can observe that the previously insoluble. Dirt (eg paint residues) and other organic and inorganic impurities are infiltrated after a short time (approx. 2 h) and can be easily cleaned off. This effect is also achieved with very small additions of significantly less than 1% active ingredient. halt (eg <200 ppm) observed. In addition, after cleaning the treated area, it can be seen that the metal surface has been impregnated with water and dirt repellent.

Cleaning is particularly efficient if it is ensured that the cleaning agent with volatile solvent acts longer on the soiled surface by using an absorbent material soaked with the cleaning agent, such as fiber cloths, fleece, sponges or the like. are applied to the surface, and in particular the surface is wrapped therewith.

It is also not yet fully understood why the special addition has its observed effects. With regard to its mechanism of action, it is currently also assumed that so-called block amphiphilic polymers are formed, in which domains are present, in which individual components of the polymer accumulate. In the case of fluoroalkyltriethoxysilane-octyltriethoxysilane poly ers, this would mean that separated s ch in the polymer and fluorine-rich ^'luorarme areas. This creates a surfactant-like structure, which would explain the cleaning effect. In addition, the polymer described can also act as a pregnnant, since the long-chain residues completely sterically hinder three-dimensional crosslinking. The polymer therefore still contains free SiOH or SiOR groups which match the Metal surface or other surfaces can interact .. After cleaning the dirt, the surfactant has access to surface metal hydroxide groups and can sometimes form very strong (covalent) bonds. This mechanism of action makes subsequent cleaning considerably easier. The polymer must have a low, oily viscosity in order to maintain its creepability. The solvent, e.g. B. petrol, supports the infiltration and loosening of dirt and is ideally composed so that it promotes the creep properties of the surfactant.

In addition to the described and extensively examined

Polymer from fluoroalkyl- and octylsilane it is also conceivable that other copolymers composed of hydrophilic, hydrophobic (alkyl, cycloalkyl) and oleophobic (fluorine-containing) residues have a comparable surfactant effect, e.g. hydrophobic-oleophobic, hydrophilic-oleophilic, hydrophilic-oleophobic. It is also conceivable that a hydrophobic-oleophobic-oleophilic mixed low molecular weight polymer has a special effect.

Be generally do not have the hydrophilic silanes alkyl, cycloalkyl, and aryl silanes ^'come application that preferably with further functional groups (halogen, amine, alcohol,' the epoxy, mercapto, sulfonyl, quaternary ammonium, phosphonium, and the like.) Substitiert can. Glycidoxypropyl (also ring opened with dialcohol) as well as aminopropyl and polyether modified silanes can be used.

Alkyl, cycloalkyl and aryl silanes are also suitable as hydrophobic-oleophilic silanes. These silanes can also be combined with other functional groups, such as halo gene, amine, alcohol, epoxy, mercapto, sulfonyl, quaternary ammonium, phosphonium, and the like. Octyl, methyl, dimethyl, propyl and trimethyl silanes are preferred.

In general, (partially) fluorinated alkyls, cycloalkyl, aryl, optionally with heteroatoms in the chain (N, 0, S, ...) or in a side chain, can be used as hydrophobic-oleophobic silanes, i.e. fluorinated silanes. There should be a distance of at least two carbon atoms between the fluoroalkyl and the Si atom. Preferred groups here are trifluoropropyl, tri-decafluorooctyl, trifluoropropyl-methyl and tridecafluoro-octyl-methyl.

Halogen, alkoxy, (preferably ethoxy, methoxy), acyloxy, -OH and oximes are suitable as hydrolyzable leaving groups.

An equal molar ratio (50:50) of the two silanes is preferred. In general, any ratio that leads to a desired creeping and surfactant effect against the dirt to be removed can be used in the given solvent.

The above silanes are hereby disclosed for use as monomers as well as for oligomers / polymers.

One is also applicable. Mixture of different surfactants with different hydrophilic-lipophilic balance values (HLB). Such surfactants can be used in conjunction with suitable solvents and co-solvents, for example as cold cleaners for engine cleaning or in particular the cleaning of printing press parts, as electronics cleaners or generally as cleaners for areas contaminated with dirt and oil. The solvent can either be volatile to ensure quick cleaning, or particularly non-volatile so that the active ingredient has a long time to infiltrate dirt.

The polymers / oligomers described is generally carried out by the sol-gel per cent ^'ess. The alkoxides of the corresponding silanes are processed into suitable polymers / oligomers by means of hydrolysis and polycondensation. The resulting alcohol can either serve as a solvent or co-solvent or, if it is disadvantageous, is removed. The polymers can then be taken up in a suitable solvent or solvent mixture. It can therefore be advantageous to add suitable organic or inorganic auxiliaries or stabilizers in order to

To bring about or improve the solubility / dispersibility of the polymers / oligomers.

Such stabilizers can be, for example, quaternary ammonium compounds, such as tetramethylammonium hydroxide (TMAH), phosphonium compounds, inorganic salts / hydroxides (NaOH, A1C1 ₃ , etc.), and betaines. Also surfactants (anionic, cationic, nonionic), colors and fragrances, acids, such as glycolic acid, citric acid or acetic acid), bases (ammonia, amines, ethanolamines), and complexing agents to keep the dirt or the metal ions in solution (eg ethylenediaminetetraacetic acid, EDTA) can be added.

Another, particularly preferred variant of the preparation of the polymers / oligomers described is the so-called water-free sol-gel process, in which anhydrous carboxylic acids are added to the silanes and an ester is formed as the solvent. In the case of the co-polymer of fluoroalkylsilane and octylsilane already mentioned several times, e.g. B. anhydrous acetic acid used for the reaction. The resulting ethyl acetate is an excellent solvent for the resulting polymer / oligomer and mediates the solubility of the polymer / oligomer in suitable cleaning agents, such as. B. gasoline fractions. Another type of preparation also includes polymer / oligomer preparation from the chlorosilanes in a suitable inert solvent, e.g. B. directly in gasoline, with defined .Water amounts (for example by passing water containing air) are added to enable polymerization with elimination of hydrochloric acid. However, this method has the disadvantage that the hydrochloric acid which is split off has a corrosive effect and. Some applications are therefore not used ^'may, or makes a removal / neutralization necessary.

The following examples illustrate the present invention: Example 1 :

25.5 g of fluoroalkyltriethoxysilane (from Degussa-Hüls) are mixed with 13.6 g of octyltriethoxysilane. In parallel, 883 g are made in a separate container. Glacial acetic acid and 0.026 g concentrated hydrochloric acid mixed.

Both mixtures are combined with stirring and aged for 20 days at room temperature.

50 g of the batch are dissolved in 950 g of gasoline (boiling point fraction 50-80 ° C).

A greasy steel surface is first roughly pre-cleaned with pure gasoline and then thoroughly cleaned of dirt with the modified gasoline and a lint-free cloth. After cleaning, the surface is rubbed with a dry, lint-free cloth. The result is a water and dirt repellent surface.

Example .2:

25.5 g fluoroalkyltriethoxysilane (from Sivento) are mixed with 13.8 g octyltriethoxysilane. 15 g of isopropanol, 2> 5 g of water and 0.03 g of concentrated hydrochloric acid are added to this mixture in succession. After 6 h and 12 h of stirring, 2.5 g of water are again metered in. After stirring for 24 h, phase separation is effected by adding 50 g of water. At this point it should be noted that such Procedure for the separation of a highly fluorinated silane product or the product obtained in this way is considered to be essential and significant, regardless of the further procedure and / or the further use of the separated substances. The pursuit of a separate patent request is therefore explicitly reserved.

The silane phase is separated off, taken up in 50 g of ethyl acetate and mixed with 190 g of gasoline (boiling point fraction 50-80 ° C.).

Example 3

The mixture is prepared as in Example 1 and 2% Aerosil R972 is added. Due to the grinding effect of the added powder, the cleaning effect of this mixture is better than that in example 1.

Alternatively, 2% hydrophobically silanized Neuburg Siliceous Earth can also be dispersed as an abrasive. In order now to be able to better clean particularly heavily soiled arrangements or objects which are particularly stubborn and / or impaired by this in terms of function, durability and / or appearance etc. using the agents according to the invention, the present invention further relates to a method for application a cleaning fluid in general and a cleaning fluid described above in particular.

It should be noted that the cleaning of objects, e.g. of pressure rollers and the like, is a massive problem. It has therefore been proposed to provide surfaces with substances which impart light cleaning properties to the surfaces. A problem then is to effect cleaning before application of soiled objects or to bring the light cleaning substances to the surface to be coated at all.

Another essential aspect of the present invention thus provides that a cleaning fluid on the one hand

Contains substance that imparts easy cleaning properties to the surface and that on the other hand it is contained in a carrier medium or fluid that infiltrates impurities.

In the case of such a cleaning fluid, impurities are first infiltrated and then encased by some of the perfluorinated substances, the surface also being covered by the highly fluorinated compound. If this evaporates, evaporates, or the carrier fluid which way can be removed. the possibly redeposable impurities no longer bond firmly to the surface.

A preferred highly fluorinated compound is realized by silane-containing light cleaning components, which can be in the form of a monomer, oligomer or polymer. It is preferred if this connection is chosen so that a small amount of crosslinking can take place. Without such crosslinking, the coating of the contaminants and the adherence of the highly fluorinated compound to the substrate are impaired. If the crosslinking is too fast and / or strong, crosslinking takes place over the contaminants before they are softened and / or detached. Instead of a covering, partial covering can be carried out, particularly in the case of non-round objects. The aforementioned cleaning agents are preferably usable.

It is preferred if the cleaning fluid is not rubbed mechanically, but instead is arranged around or on the object in an absorbent material with exposure times of, for example, in particular 30 to 45 minutes. After this, the impurities are largely softened and / or crawled under and / or lifted off and encased, and the object can be used for further use after being simply wiped off, at least to a very large extent. This part of the invention is described below only by way of example without reference to a drawing.

In a preferred variant, a highly fluorinated silane-based compound is taken up in white spirit. The silane compound is selected so that it can react well with the impurities to be removed, in the present case flexographic printing inks, even after they have hardened and deposited. Suitable substances are described above.

Then a printing roller is wrapped with paper towels and ^■ the paper towels are soaked with the cleaning fluid. The soaked wipes are left around the platen for 30 to 45 minutes. Then they are removed from the pressure roller with abrasive movement.

The result is a thoroughly cleaned pressure roller.

If the treatment is repeated several times at intervals between which it can be used, the cleaning effect improves. It should be mentioned that such a procedure also for printing blocks, plates and the like. is possible .

Such a pressure roller, which is easy to clean, can further be designed according to the invention in a special way. The present invention addresses this further with ^objects' and their surfaces. It is in fact often desirable to provide an object with a hydrophilic or, more generally, fluid-philic or liquid-loving surface. This is the case, for example, if the fluid is to be transferred from a first to a second location on the surface. A typical case is in printing presses where ink has to be transferred.

It has been proposed to provide flamed, sputtered or similarly applied layers on the surfaces of such transferring objects, for example made of CrO ₂ . With these, the hydrophilicity, as far as the mechanisms are understood, results from the structuring of the surface.

Areas that appear to be flat in the form of raster electron images can arise, for example. The rough outline of the flatbread itself determines a microstructure, but in the areas where two or more flatbreads lie on top of one another, they are more substructured, i.e. they have fine substructure pores where the flatbreads are not tightly packed. The hydrophilicity is now attributed to the sponge-like and / or pore-like, but in any case structured surface, insofar as it is assumed that fluid penetrates into the pores and thus the fluid absorption capacity is increased.

However, it is problematic, for example in the printing machine sector, that pure solvent and / or pure fluid, which can be completely detached, is not applied, but pigments and the like are often present. These then settle in or in front of the pores and lead both to a deteriorating fluid philia and to overall contamination.

An object with a surface which is micro-constructed to increase its fluid carrying and / or receiving and / or transfer ability is therefore further proposed, characterized in that the micro structure has substructures and a substructure seal is provided.

It is therefore fundamental that the perception, which appears paradoxical per se, that although the structuring was carried out in order to microstructure the fluid carrying and / or taking up and / or transfer ability, the amount of fluid is increased by repeated transfer by sealing can. Advantages are nevertheless achieved by achieving a substructure seal. It was recognized that such small capillary openings are possibly closed, but that with a suitable design of the seal, enough fluid can nevertheless be fixed in the entrance area of the capillary to the seal, which may and ideally only ideally only very small and smallest pores, the small and the smallest pores can in particular be a factor of two, in particular a factor of 5, particularly preferably an order of magnitude smaller than the macrostructuring, which, however, can itself be sealed.

The microstructure does not have to be periodic, but can be stochastic and / or quasi-stochastic. In particular, a non-smooth surface can first be provided, in particular with a basic structure of higher amplitude and lower spatial frequency, on which a fine structure with lower amplitude and higher spatial frequency is and / or will be built.

It is possible and preferred if the microstructure is formed by areas lying flat and / or flat on top of one another. This can be achieved if the microstructure is formed by material hitting the surface during manufacture. The microstructure can be formed by spraying and / or flaming material, in particular by a metal oxide, in particular CrO ₂ .

The substructure seal can have oleophobic properties and / or be completely oleophobic. At the same time, the seal can be hydrophilic and / or hydrophobic. It is astonishing here that in particular a hydrophobic sealing of a hydrophilic structure can permanently give better results than an unsealed surface.

It is also possible to adapt the surface energy of the object to the fluid and neighboring objects from or to which it is transferred. This adjustment of the surface energy can be achieved in particular by coating the parts involved, for example those that are adjacent to one another during operation. A coating composition with very low surface energy is known for example from EP 0 587 667 B1. The main claim of this previously published document specifies an organometallic coating composition which has a group which is perfluorinated with an average of 5 to 30 fluorine atoms and which are bonded to one or more aliphatic carbon atoms which are separated from M by at least two atoms. Such a coating composition has a low surface energy. If, for example, alkyl groups are incorporated instead of some or all of the fluorine atoms, the surface energy of the resulting composition or of the surfaces treated with the composition increases, and the more, the fewer fluorine atoms are exchanged. The surface energies are typically set between 10 mJ / m ² and 80 mJ / m ² , preferably between 15 mJ / m ² and 70 m / m ² . Care is preferably taken to ensure that the composition used for the coating is particularly low-viscosity, that is to say it flows well into the pores and can thus act primarily where it is desired, namely in the substructure area.

The composition is also preferably applied very diluted to the structured surface. The background to this is that the substructures to be sealed, since they are only subjected to a low abrasive load, also require only small layer thicknesses and at the same time the thin layers enable the sealing of only the finest pores and / or substructures, but not also those pores which, owing to their Size does not become so easily contaminated by pigment deposits or the like itself, so it does not require a seal, since it permanently contributes to the fluid philia of the object.

The sealing can be done with fluorinated, especially with multiple fluorinated substances. Such can be coating compositions based on polycondensates of one or more hydrolyzable compounds of at least one element M from the main groups III to V and the subgroups XI to IV of the periodic table, at least some of these compounds in addition to the hydrolyzable groups A also has non-hydrolysable carbon-containing groups B and the total molar ratio of groups A to groups B in the underlying monomeric starting compounds is 10: 1 to 1: 2, with a predetermined proportion of the composition are groups B, groups B ¹ , which have an average of 5 to 30 fluorine atoms, which are bonded to one or more aliphatic carbon atoms and are separated from M by at least two atoms, and further with a second proportion of the Composition of the groups B are those groups B ^{λ <} which are selected such that there is a higher surface energy for them, which is above 25 mJ / m ² , in particular above 60 m / m ² . The lower value of 25 mJ / m ² differs comparatively little from that of the highly fluorinated composition components, which allows fine adjustment, while the second, higher value creates a wider range of adjustment options. In particular, the surface energy of the second portion can also be higher, for example 70 or 80 mJ / m ² . It should be mentioned that when choosing the second component, it is of primary and primary importance that, on the one hand, the required high surface energy is given and, on the other hand, in the mixture with the perfluorinated first component there is still a sufficient and therefore particularly good one Substrate crosslinking composition results.

It can be provided that the seal has, in particular, antistatic properties, which particularly promotes pigment removal during transfer and / or that the scratch resistance is increased. This can be accomplished by using suitable nanoparticles in the sealing composition.

It should be mentioned that particles, preferably nanoparticles which remain in the coating, can be introduced into the seal, in particular by means of high-frequency eddy currents. When the particles are heated by the high-frequency electromagnetic alternating field, the entire layer also heats up. In this way, the composition can be cured without the. need to warm up the entire item. Alternatively, the coating can also be heated with a sufficiently powerful hot air blower designed for achieving sufficiently high temperatures and / or an infrared light source. The sealing can be carried out with a solution which does not contain fluorosilane, which has the advantage that local micelle formation in the pores is reliably avoided and the sealing is improved. Instead, nanoparticles and active binding phases can be contained according to the invention.

According to the invention, the proposed sealing solution is a solution which contains the following components: silica sol, silica esters which are anhydrolyzed or partially hydrolyzed and / or condensed and / or organically modified silica esters, the organic modification being effected by groups which make it possible to couple the monomer , which is applied later to achieve the surface properties. The anhydr ^'olisieren, condensing, etc. of the silicate with the result that, firstly, the pores can be locked concluded better and secondly, a chemically stable compound to the substrate, such as chromium dioxide, as it can be found on chrome-plated surfaces of printing machines can be obtained ,

As nanoparticles, which can also be contained in the sealing solution, yttrium salts or nanoparticles ITO, ATO, FTO or

Nano-sized metal particles are used. Other nanoparticles can also be used. The reason for using nanoparticles is that the bulk component shrinks when dried, which would result in renewed cracks after penetration into the pores to be filled. The nanoparticles prevent the formation of cracks when the sealing solution shrinks, so they serve as filling material. It is preferred if they have diameters of e.g. 1/10 of. have typically filled pores so that they can penetrate them well.

It is also possible not to apply monomers, in particular fluorinating monomers, to an underlying sealant, but rather directly to, for example, objects present in a printing press, in particular rollers, anilox rollers, etc. This is possible, although many rollers have metal surfaces. The reason why this is possible is the fact that metal surfaces, as long as they are not precious metals, are regularly oxidized on the surface, ie oxides / hydroxides and the like. With kinetic activation (heating) of the substance to be applied and / or the surface to be coated, sufficient energy is then available to cause condensation. During the condensation, bonds form on the one hand between the metal surface and the monomer and, on the other hand, under the condensing monomer molecules, so that there is at least partial crosslinking on the surface, which increases the resistance of the coating formed from the layer produced by the monomer elevated. It is preferred that the surface is cleaned beforehand, in particular is free of grease, which can be achieved with conventional grease-dissolving solvents and / or processes.

The monomer can be used activated or not activated. The activation takes place by installing / converting reactive groups, which can be done, for example, by adding water or the like to the monomer. Fluorine compounds are conceivable as monomers here, in particular with the following properties: silicon-bonded perfluorinated groups with a spacing of 2 C atoms spacer, the use of fluorinated Si compounds having the advantage that particularly durable coatings result, specifically due to the fact that bonds form between Si and the metal hydroxide present on the surface and that this leads to very good three-dimensional crosslinking of the monomers. It is also possible to use fluorinated organic compounds, but there are less durable compounds, so that a more frequent coating and renewal of the coating is required; The advantage here is that the organically fluorinated compounds can possibly be produced more cheaply and thus the individual coating can be carried out more cheaply, which can lead to an overall cost advantage.

In the fluorinated compounds, it is preferred to use alipathic, long-chain or to use cyclic aliphatic or aromatic compounds. It is preferred to use CF ₂ groups in the compounds because CFH groups and the like are highly toxic.

The invention can also be used in flexographic printing. An antistatic coating is particularly important when coating rubber rollers that are particularly sensitive to paper dust and that give a poorer print image when they are present. However, the use of a coating with antistatic properties also has positive effects on other parts of a printing press. This applies equally to rolls made of or with ceramic material. It is also possible to carry out an electrostatic coating, in particular of a primary sealing layer, ie to spray the coating electrostatically so that particularly good penetration takes place. The electrostatic coating also improves the properties of the object positively if only and only the substructures have been sealed.

The required electrostatic properties of the coating can be shaped and achieved by nanoparticles / structures with groups capable of dissociation, in particular OH groups, the dissociation resulting in charge separation and chargeability.

A porous roller can preferably be coated in the moistened state. The moistening can in particular be carried out with the same solvent as is used for the coating composition. The consequence of the moistening is then that solvent penetrates into the capillaries of the porous structures, for example overlaid material sheets. If the coating dries out, the solvent will evaporate away from the coating surface. It cannot be avoided that solvent remains in the capillaries of the microstructure, since the capillary forces are greater than the vapor pressure of the solvent. If the coating is then heated for the purpose of curing or the like, the vapor pressure of the solvent remaining in the capillaries rises so much that vapor is formed. With conventional coatings, this may not be able to escape because the surface drying is vapor-tight. In contrast to this, in the coatings used with nanostructures and / or particles within the substructures there is still sufficient porosity for evaporation in order to ^' evaporate the solvent residues from the capillary to enable without the surface of the already cured or at least hardened coating material bursting or the sealing is impaired.

The invention is only described by way of example:

A roller of a printing machine provided with a warped chrome structure is coated with a coating in accordance with EP 0587 667 B1. The result is a pressure salt that does not need to be cleaned for the first 14 days of operation and can then be easily cleaned with an oil rag for about six months. This is attributed to the good transferability of the color due to the changed surface energy.

It should be noted that the effect disappears comparatively quickly with smooth rolls, that is to say rolls not coated with a warty coating.

After 1700 copies, there was no longer any effect. With a sandblasted or shot-peened, but otherwise smooth roller, it was possible to print up to 11,000 copies until the effect disappeared. In comparison to the chrome arsenic structure, both may be due to the very high abrasion of the coating on a smooth or almost smooth roller, but is not yet fully understood.

If no rollers that are not yet used are being coated, but are already being operated, such as ^' long' after a previous coating, these must be cleaned. This cleaning is known per se in the prior art. It is possible to blast with sand, baking powder, shot peening, cryosteen, corona, ultrasound, etc. Furthermore, the laser scanners known from aircraft paint stripping can be used. Because of the fine well structures, anilox rollers can also be cleaned by blasting with nanopowder to be conducted, in particular, in an at least quasi-closed circuit. The cleaned rollers can then be coated.

It should be mentioned that while the present invention was described with reference to printing presses and the color to be transferred, The advantages of cleaning that become less necessary also result in other continuously and / or cyclically operating machines in which readily adhering, difficult-to-remove materials are to be transferred or transferred. An example of this are machines that produce PVC films, in which silicone oils currently have to be applied to a large extent on the heating rollers guided through the starting fluid in order to ensure the transfer of the PVC material. A coating according to the invention is also advantageous here. Furthermore, a coating according to the invention is advantageous for the belt sieves etc. used there.

Claims

claims

1. Composition for the production of a surfactant with a combined cleaning and impregnation action, comprising a long-chain non-fluorinated silane and a perfluorinated silane, the oligomer / polymer to be formed from the two silane compounds by hydrolysis and condensation forming a linearly cross-linked polysiloxane network , which has free reaction sites capable of three-dimensional crosslinking.

2. Composition according to claim 1, characterized in that the non-fluorinated silane is a hydrophilic or hydrophobic silane.

3. Composition according to claim 1, characterized in that the fluorinated silane is an oleophobic silane.

4. Composition according to claim 2, characterized in that the non-fluorinated silane is octyltriethoxysilane.

5. Composition according to claim 3, characterized in that the fluorinated silane is a fluoroalkyltriethoxysilane.

6. The composition according to claim 1, characterized in that the oil to be formed from the two silane compounds gomer / polymer is soluble in an organic solvent.

7. Composition according to claim 6, characterized in that the solvent is selected from the group consisting of esters, ketones, alkanes, aromatics, cycloalkanes, ethers, alcohols and mixtures thereof.

8. Composition according to one of the preceding claims, characterized in that the silane compounds are present in the same molar ratio.

9. Process for cleaning and impregnating areas contaminated with dirt and oil, in particular steel surfaces, characterized by the steps

10. Preparation of an oligomer / polymer from a long chain silane and a perfluorinated silane; and

11. Apply the oligomer / polymer to the surface to be treated.

12. The method according to claim 9, characterized in that the oligomer / polymer is dissolved in a suitable solvent before application to the surface to be treated.

13. The method according to any one of claims 9 or 10, characterized in that the oligomer / polymer by means of a sol-gel process by processing the alkoxides of the corresponding silanes by means of hydrolysis and polycondensation will be produced.

14. The method according to any one of claims 9 or 10, characterized in that the oligomer / polymer is produced by means of an anhydrous sol-gel process in which anhydrous carboxylic acids are added to the starting silanes.

15. The method according to claim 12, characterized in that anhydrous acetic acid is used as the carboxylic acid.

16. The method according to claim 10, characterized in that suitable organic or inorganic auxiliaries and / or stabilizers are added to the solution.

17. The method according to claim 14, characterized in that the auxiliaries are selected from the group consisting of quaternary ammonium compounds, phosphonium compounds, inorganic salts, hydroxides and betaines.

1-8. ' Method according to claim 15, characterized in that it is tetramethylammonium hydroxide (TMAH).

19 .. The method according to claim 14, characterized in that the auxiliary substances are anionic, cationic or nonionic surfactants or surfactant mixtures.

20. The method according to any one of claims 10 to 12, characterized in that the solution further substances such as dyes and fragrances, acids, bases or complexing agents be added.

21. The method according to claim 10, characterized in that the amount of oligomer / polymer in the solvent is less than 1% by volume.

22. Use of the composition according to one of claims 1 to 8 for cleaning and impregnation of areas contaminated with dirt and oil, in particular steel surfaces.

23. Use of the composition according to one of claims 1 to 8 for cold cleaning of engines and for cleaning printing press and electronic parts.

24. Cleaning fluid with a highly fluorinated component and a base fluid containing it, in which the base fluid is then arranged to swell and / or detach or detach contaminants and the long-chain, in particular by fluorinated compound, is provided with a functional group which it is possible for the highly fluorinated component to adhere to particulate contaminants.

25. A cleaning fluid according to the preceding claim, wherein the fluorinated compound is a highly fluorinated silane.

26. Cleaning fluid, in which the highly fluorinated compound is a compound according to EP 0 587 667 B1 relating to coating compositions based on fluorine-containing inorganic polycondensates.

27. Cleaning fluid according to one of claims 22 to 24, wherein the carrier fluid is a particularly volatile organic solvent.

28. Cleaning fluid, in which the carrier fluid is represented by a mineral oil fraction, in particular a volatile one.

29. A method for cleaning objects, characterized in that the object is wrapped with an absorbent material and / or such is applied to the object, which is suitable for ensuring a slow evaporation of solvents, the absorbent material Cleaning fluid, in particular according to one of the preceding claims, before or after being placed on or wrapped around, the absorbent material around the object to be cleaned for at least 3, preferably at least 30, particularly preferably 45 minutes. is left and then removed from the object.

30. The method according to the preceding claim, characterized in that the object ^{•• is} rubbed off with the soaked absorbent material after the predetermined exposure time.

31. The method according to any one of the two preceding claims, characterized in that fibrous absorbent material, in particular cellulose-containing wipes, are selected as the absorbent material.

32. Object with a surface that is enlarged in a microstructured manner to increase its fluid carrying and / or absorbing capacity, characterized in that the microstructure has substructures and a substructure seal is provided.

33. Object according to the preceding claim, characterized in that, characterized in that the substructures are at least five times smaller than the microstructures.

34. Object according to one of the preceding object claims, characterized in that the microstructure is stochastic and / or quasi-stochastic.

35-. Object according to one of the preceding object claims, characterized in that a non-smooth surface is initially provided, in particular with a basic structure of higher amplitude and lower spatial frequency, on which a fine structure with lower amplitude and higher spatial frequency is built and / or is built ,

36. An article according to one of the preceding article claims, characterized in that the microstructure is formed by areas lying flat and / or flat on top of one another.

37. An article according to one of the preceding article claims, characterized in that the microstructure is formed by material hitting the surface during manufacture.

38. An article according to one of the preceding article claims, characterized in that the microstructure is formed by spraying and / or flaming material.

39. An article according to one of the preceding article claims, characterized in that the microstructure is formed by a metal oxide, in particular Cr0 ₂ ;

40. Item according to one of the preceding item claims, characterized in that the substructure seal is an oleophobic seal.

41. An article according to one of the preceding article claims, characterized in that the substructure seal is a hydrophilic seal.

42. An article according to one of the preceding article claims, characterized in that the substructure seal is a hydrophobic seal.

43. Arrangement with at least one object according to one of the preceding object claims and a fluid transfer means for transferring fluid to and / or for receiving fluid from the object, the fluid transfer means having a predetermined surface energy with respect to the fluid to be transferred, thereby characterized in that the substructure seal has a surface energy which favors the desired fluid transfer.

44. An article according to one of the preceding article claims, characterized in that the substructures are sealed with fluorinated substances.

45. An article according to the preceding article claim, characterized in that the substructures are sealed with multi-fluorinated substances.

46. An article according to one of the preceding article claims, characterized in that the sealing substances have antistatic properties.

47. An article according to one of the preceding article claims, characterized in that the sealing substances increase the scratch resistance.

48. Object according to one of the preceding object claims, characterized in that this part of a printing press, in particular a roller, in particular an anilox roller, embodies.

49. An article according to one of the preceding article claims, characterized in that the seal is resistant to high temperatures, in particular is resistant up to above 6 ° C., preferably above 80 ° C.

50. An article according to one of the preceding article claims, characterized in that the seal is thermally cured.