Conductive epoxy resin coating and electrostatic dissipative floor

Abstract

The present invention relates to the use of a combination of carbon nanotubes and at least one amine of formula (I) for producing a conductive epoxy resin coating, and to an electrostatic dissipative floor system comprising the conductive epoxy resin coating. The object of the present invention is to provide a conductive epoxy resin coating having electrical resistance that is largely unaffected by humidity. [Solution] The present invention provides an easily workable, robust, electrostatically dissipative epoxy resin floor system having substantially constant electrical resistance, which is highly aesthetic, well-degassed, and has a flat surface.

Description

[Technical Field]

[0001] This invention relates to conductive epoxy resin coatings and their use in electrostatic dissipative floors. [Background technology]

[0002] Electrostatic dissipative flooring (also known as ESD flooring) is well known. It helps dissipate static charge generated in a room through footwear and the floor to the ground, for example, as a result of walking or vehicle traffic. This can prevent spontaneous electrostatic discharge, potentially leading to defects or malfunctions in the manufacture or handling of electrostatically sensitive products or equipment.

[0003] Electrostatically dissipative floors must have sufficiently low grounding resistance to ensure reliable dissipation of electric charge, but must also possess sufficient dissipation to avoid harming human health in the event of contact with electric current. Standards exist for such floors that describe test methods for their electrostatic and electrical properties. DIN EN 61340-4-1 describes test methods for measuring the electrical resistance of floor finishes and laid floors, and DIN EN 61340-4-5 assesses electrostatic safety in terms of electrical resistance, as well as the potential for combined charging of humans, footwear, and floor finishes.

[0004] Epoxy resin-based floors are particularly robust in relation to mechanical stress and stability against many materials. Therefore, they are especially suitable for demanding industrial manufacturing rooms. Epoxy resin-based electrostatic dissipative floor systems must achieve a set of performance characteristics: reliable adhesion to various substrates and installation with minimal complexity. The electrostatic charge absorbed by the floor should be reliably dissipated downwards. For this purpose, a conductive system, including grounded copper ribbons or copper wires, is laid beneath the coating. The epoxy resin coating should be easily installable and coexist with the underlying conductive system, and after curing, it should have a visually pleasing, homogeneous surface, possessing both high hardness and low brittleness. For this purpose, the epoxy resin coating should have low viscosity with good leveling and degassing properties, and a long open time at ambient temperature, but nevertheless, it should cure very rapidly and be free from any curing defects, such as residual tack, spots, or clouding. For high slip resistance, sand may be sprinkled on the surface and covered with a sealant. After hardening, the coated floor will be approximately 10 5 ~10 8 It should have electrical resistance in the ohm range and be robust and durable.

[0005] Floors made of synthetic resins such as epoxy resin are insulators. Various methods exist to achieve electrical conductivity. Known methods involve using soluble ionic liquids or organic salts in the synthetic resin matrix, which impart electrical conductivity. However, this slows curing, significantly reduces the mechanical and chemical durability of the floor, and the electrical resistance is greatly affected by the humidity at the time. In addition, conductive solid particulate matter may be added. A suitable example for this purpose is metal, but they have a strong inherent color, and due to their high specific gravity, they settle to the bottom of the container while the composition is still liquid, making uniform stirring and dispersion into the coating difficult. This results in heterogeneous electrical resistance and the creation of zones with too little electrical conductivity. Similarly known is the addition of conductive carbon black or graphite, which achieves reliable electrical conductivity, but because these substances are strongly black, the resulting coating is a very strong gray to black, which is generally undesirable for manufacturing floors. Similarly known are microfibers made from carbon, called carbon fibers. However, these also exhibit difficulties in achieving uniform mixing and tend to aggregate, which remains visible even after curing, resulting in an uneven resistance and an unattractive surface. More recently, carbon nanotubes (CNTs) have become known, and these can also be used as conductive fillers. These are nanotubes made from carbon, and their walls consist of individual graphite layers called graphene. Even when used in very small amounts, carbon nanotubes still provide good electrical conductivity with uniform resistance over a large area, and are hardly affected by humidity. However, because they have a high surface area, they have a significant thickening effect. When applied, this reduces leveling and makes degassing, where trapped air in the form of rising bubbles escapes and bursts on the surface, more difficult.Therefore, conductive coatings based on carbon nanotubes require greater care and time during application, and after curing, they exhibit a somewhat uneven surface due to incomplete degassing.

[0006] An epoxy resin-based electrostatic dissipative floor is described, for example, in European Patent No. 1,437,182, in which carbon fibers are used as a conductive filler.

[0007] For example, European Patent No. 3,180,383 or European Patent No. 3,344,677 describes an amine of formula (I) as a curing agent for epoxy resins. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Therefore, the object of the present invention is to provide a conductive epoxy resin coating having electrical resistance that is hardly affected by humidity, which exhibits good degassing and leveling properties, cures rapidly, and ultimately has a flat, aesthetically pleasing surface, even when working with no or only a small amount of non-miscible thinner, and is suitable as an element of an electrostatic dissipation floor system. [Means for solving the problem]

[0009] Remarkably, this objective is achieved by using carbon nanotubes in combination with at least one amine of formula (I) as described in claim 1. Epoxy resin coatings containing carbon nanotubes have reliable electrical conductivity, and their electrical resistance is largely unaffected by humidity. However, ultrafine carbon nanotubes make leveling and degassing considerably more difficult. In particular, in the case of filled pigment-colored coatings, degassing becomes even more difficult, and even after processing the still-liquid coating with a spiked roller or spiked footwear, the result is a somewhat uneven surface with fine, unruptured bubbles. When combined with an amine of formula (I), remarkably, significantly improved leveling and remarkably improved degassing are possible, thereby making the work easier and resulting in an attractive, particularly flat surface. By using the present invention, pigment-colored coatings with high color intensity, and remarkably, transparent coatings, with the amine of formula (I) enabling particularly high transparency, are possible. The cured coating obtained using the present invention has a visually pleasing, flat surface, a combination of high hardness and low brittleness, high robustness against mechanical and chemical stress, and electrical conductivity that is evenly distributed across the entire surface and is hardly affected by humidity. By using the present invention, it is possible to create a conductive coating that releases particularly little organic matter after curing, making it suitable for use in hospitals or clean rooms.

[0010] The epoxy resin coating obtained using the present invention enables an electrostatic dissipative floor system that offers good and easy application, particularly low discharge, and meets the highest aesthetic requirements. This allows for floor systems with colored, particularly flat, surfaces, as well as floor systems with slip-resistant, transparently sealed sand-coated surfaces.

[0011] A further aspect of the invention is the subject matter of the further independent claims. Particularly preferred embodiments of the invention are the subject matter of the dependent claims.

Mode for Carrying Out the Invention

[0012] The present invention provides the use of a combination of carbon nanotubes and at least one amine of the following formula (I) for producing a conductive epoxy resin coating: Z-NH-A-NH-CH2-Y (I) (wherein, A is a divalent C2-C 15 alkylene, cycloalkylene, or arylalkylene group optionally containing one or more nitrogen atoms or ether groups, Z is H, or -CH2-Y, and Y is H, or a C1-C 12 alkyl, cycloalkyl, arylalkyl, or aryl group), here, the amine of formula (I) contains a total of at least eight carbon atoms. [[ID=2�]]

[0013] "Carbon nanotubes" refers to carbon tubes having a diameter in the nanometer range, particularly in the range of 1 to 50 nm, and a wall composed of one ply or several plies of graphene (i.e., carbon having carbon atoms arranged in a cyclic manner).

[0014] A composition is said to be "storage-stable" if it can be stored in a suitable container at room temperature for a long period, typically at least 3 months to a maximum of 6 months or more, and during this storage, there is no change in its coating or use performance that would interfere with its use.

[0015] "Thinner" refers to a substance that is soluble in an epoxy resin, reduces its viscosity, and is not chemically incorporated into the epoxy resin polymer during the curing process.

[0016] "Liquid epoxy resin" refers to industrial polyepoxides that have a glass transition temperature of less than 25°C.

[0017] "Molecular weight" refers to the molar mass (grams per mole) of a molecule. "Average molecular weight" is the number average of M of a polydisperse mixture of oligomeric or polymeric molecules. n This refers to [the specific characteristic]. It is determined by gel permeation chromatography (GPC), compared to polystyrene as the standard.

[0018] "Pot life" refers to the time period after mixing the components of an epoxy resin composition during which the composition can be processed without loss.

[0019] "Gelation time" refers to the time interval between mixing multiple components of an epoxy resin composition and the time it takes for the mixture to gel.

[0020] A "primary amino group" refers to an amino group that is bonded to a single organic group and supports two hydrogen atoms; a "secondary amino group" refers to an amino group that is bonded to two organic groups (which may together form part of a single ring) and supports one hydrogen atom; and a "tertiary amino group" refers to an amino group that is bonded to three organic groups (two or three of which may form part of one or more rings) and does not support any hydrogen atoms.

[0021] "Amine hydrogen" refers to the hydrogen atom of a primary or secondary amino group.

[0022] "Aliphatic" amine hydrogen refers to an amino group bonded to an aliphatic carbon atom.

[0023] "Amine hydrogen equivalent" refers to the mass of an amine or amine-containing composition containing 1 molar equivalent of amine hydrogen.

[0024] Substance names beginning with "poly," such as polyamines or polyepoxides, refer to substances that formally contain two or more of the functional groups represented by those names per molecule.

[0025] "Room temperature" refers to a temperature of 23°C.

[0026] The abbreviation wt% (weight percent) refers to the mass ratio of the components of a composition or molecule based on the entire composition or molecule, unless otherwise specified. In this specification, "mass" and "weight" are used synonymously.

[0027] All industry standards and criteria described herein relate to the edition in effect on the date of the initial filing.

[0028] Carbon nanotubes are industrially manufactured and commercially available in various qualities. They possess properties that make them of interest in a wide range of applications. In particular, they are electrically conductive.

[0029] A particularly suitable type of carbon nanotube is what is called a single-walled carbon nanotube.

[0030] These are preferably used in the form of a dispersion in a liquid carrier substance, particularly an epoxy resin composition, which has good compatibility with the liquid, especially an alkyl glycidyl ether, fatty acid ester, or ethoxylated alcohol.

[0031] Preferably, alkyl glycidyl ethers, especially C, which are also used as reactive diluents for epoxy resins. 12 ~C 14 This is a dispersion containing 10% by weight of carbon nanotubes in an alkyl glycidyl ether. Such dispersions are commercially available, for example, as Tuball® Matrix207 (made of OCSiAl).

[0032] Even extremely small amounts of carbon nanotubes by weight enable good electrical conductivity, but also result in significant increases in viscosity, leveling properties, and a certain degree of darkening of the coating.

[0033] It is preferable to use carbon nanotubes in an amount such that the epoxy resin coating has a light color that is sufficiently usable as a colored coating with light-colored pigments, or as a transparent sealant.

[0034] A quantity in the range of 0.001% to 0.1% by weight, based on the entire epoxy resin coating, is preferred.

[0035] Amounts in the range of 0.001% to 0.05% by weight, relative to the entire epoxy resin coating, are particularly preferred.

[0036] Therefore, a dispersion containing 10% by weight of carbon nanotubes is used in an amount of preferably 0.01% to 1% by weight, and more particularly 0.01% to 0.5% by weight, relative to the entire epoxy resin coating.

[0037] Within this range, the desired electrical conductivity and non-excessive darkening can be achieved.

[0038] The pigment-colored coating preferably contains an amount in the range of 0.01% to 0.1% by weight, and more particularly 0.01% to 0.05% by weight.

[0039] The transparent coating preferably contains an amount in the range of 0.001% to 0.01% by weight, and more particularly 0.001% to 0.005% by weight.

[0040] In the amine of formula (I), A is preferably selected from the group consisting of the following: 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,4-butylene, 1,3-butylene, 2-methyl-1,2-propylene, 1,3-pentylene, 1,5-pentylene, 2,2-dimethyl-1,3-propylene, 1,6-hexylene, 2-methyl-1,5-pentylene, 1,7-heptylene, 1,8-octylene, 2,5-dimethyl-1,6-hexylene, 1,9-nonylene, 2,2(4),4-trimethyl-1,6-hexylene, 1,10-decylene, 1,11-undecylene, 2-butyl-2-ethyl-1,5-pentylene, 1,12-dodecylene , 1,2-cyclohexylene, 1,3-cyclohexylene, 1,4-cyclohexylene, (1,5,5-trimethylcyclohexane-1-yl)methane-1,3,4(2)-methyl-1,3-cyclohexylene, 1,3-cyclohexylenebis(methylene), 1,4-cyclohexylenebis(methylene), 1,3-phenylenebis(methylene), 1,4-phenylenebis(methylene), 3-oxa-1,5-pentylene, 3,6-dioxa-1,8-octylene, 4,7-dioxa-1,10-decylene, 3-aza-1,5-pentylene, 3,6-diaza-1,8-octylene, 4,7-diaza-1,11-decylene, and 3-aza-1,6-hexylene.

[0041] A preferably does not contain nitrogen atoms and does not contain ether groups.

[0042] A is preferably a C2-C8 alkylene group, particularly 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,4-butylene, 1,3-butylene, 1,5-pentylene, 1,6-hexylene, 2-methyl-1,5-pentylene, 1,7-heptylene, or 1,8-octylene. These amines of formula (I) enable particularly good leveling properties.

[0043] A is more preferably 1,2-ethylene. These amines of formula (I) enable particularly good leveling, particularly good degassing, and particularly rapid curing.

[0044] Z is preferably H.

[0045] In the amine of formula (I), Y is preferably selected from the group consisting of: H, methyl, ethyl, propyl, isopropyl, butyl, pentyl, heptyl, hept-2-yl, phenyl, naphthyl, and cyclohexyl.

[0046] More preferably, Y is phenyl or cyclohexyl, particularly phenyl. Such amines of formula (I) enable particularly rapid curing and a particularly attractive surface with high gloss.

[0047] The most preferred is the amine of formula (I), in which A is 1,2-ethylene, Z is H, and Y is phenyl.

[0048] The amine in formula (I) is N-benzylethane-1,2-diamine. It contains carbon nanotubes and enables epoxy resin coatings with particularly good leveling properties, especially flat and well-degassed surfaces, and extremely rapid curing properties.

[0049] Among these, the amine of formula (I) where Z is H may contain a certain amount of dialkylated amine, i.e., the corresponding amine where Z is ---CH2-Y. It preferably contains 30% by weight or less, more preferably 20% by weight or less, and particularly 15% by weight or less of dialkylated amine. Among these, it is most preferable that the amine of formula (I) where Z is H is used with a purity of at least 95% by weight.

[0050] It is preferable to prepare the amine by partially alkylating the amine of formula (I) or at least one amine of formula H2N-A-NH2 using at least one alkylating agent.

[0051] The alkylation is preferably a reductive alkylation using an aldehyde and hydrogen as alkylating agents.

[0052] The reductive alkylation is preferably carried out in the presence of a suitable catalyst. Suitable catalysts include palladium / carbon (Pd / C), platinum / carbon (Pt / C), Adams catalyst, or Raney nickel, particularly palladium / carbon or Raney nickel.

[0053] When molecular hydrogen is used, its reductive alkylation is preferably carried out in a pressure device at a hydrogen pressure of 5 to 150 bar, particularly 10 to 100 bar. This can be carried out in a batch process, or preferably a continuous process.

[0054] The reductive alkylation is preferably carried out at a temperature in the range of 40 to 120°C, and more particularly in the range of 60 to 100°C.

[0055] When using a small amount of volatile amine, particularly ethane-1,2-diamine, it is preferable to use it in a stoichiometric excess relative to the aldehyde, and after alkylation, some or all of the unreacted amine is removed from the reaction mixture, particularly by distillation or stripping. If desired, the reaction mixture may then be further purified, particularly by partially or completely removing the dialkylated amine of formula (I), in which Z is H, by means of distillation, in which Z is ---CH2-Y.

[0056] The amine of formula (I) may be in free form or in the form of an adduct with the following: at least one epoxy resin, particularly at least one aromatic diepoxide having an epoxy equivalent weight in the range of 110 to 200 g / mol, preferably 150 to 200 g / mol, particularly bisphenol A diglycidyl ether and / or bisphenol F diglycidyl ether. This adduct is prepared in excess of the amine, in particular by using at least 1.3 mol of the amine of formula (I) per mole of epoxy group.

[0057] The amine of formula (I) is preferably used in such an amount that at least 5%, preferably at least 10%, of the total amine hydrogens present in the epoxy resin coating come from the amine of formula (I). In particular, 5% to 70%, preferably 5% to 50%, of the total amine hydrogens present come from the amine of formula (I). This also includes amine hydrogens from adducted amines of formula (I).

[0058] The present invention further includes, and also provides, conductive epoxy resin coatings obtained from the described uses: - At least one type of liquid epoxy resin, - At least one amine of formula (I), - Carbon nanotubes, and - At least one further component selected from the group consisting of further amines, accelerators, fillers, thinners, surfactants, and stabilizers.

[0059] Suitable liquid epoxy resins are aromatic epoxy resins, particularly glycidyl ethers of the following: - Bisphenol A, bisphenol F, or bisphenol A / F (wherein, in the preparation of these bisphenols, A represents acetone and F represents formaldehyde, used as a reactant. In the case of bisphenol F, positional isomers, more particularly those derived from 2,4'- or 2,2'-hydroxyphenylmethane, may be present); - Dihydroxybenzene derivatives, such as resorcinol, hydroquinone, or catechol; - Further bisphenols or polyphenols, e.g., bis(4-hydroxy-3-methylphenyl)methane, 2,2-bis(4-hydroxy-3-methylphenyl)propane (bisphenol C), bis(3,5-dimethyl-4-hydroxyphenyl)methane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane (bisphenol B), 3,3-bis(4-hydroxyphenyl)pentane, 3,4-bis(4-hydroxyphenyl)hexane, 4,4-bis(4-hydroxyphenyl)heptane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 2,4-bis(3,5-dimethyl-4-hydroxyphenyl)-2-methylbutane, 1,1-bis (4-hydroxyphenyl)cyclohexane (bisphenol Z), 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (bisphenol TMC), 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 1,4-bis[2-(4-hydroxyphenyl)-2-propyl]benzene (bisphenol P), 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene (bisphenol M), 4,4'-dihydroxydiphenyl (DOD), 4,4'-dihydroxybenzophenone, bis(2-hydroxynaphthi-1-yl)methane, bis(4-hydroxynaphthi-1-yl)methane, 1,5-dihydroxynaphthalene, tris(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, bis(4-hydroxyphenyl) ether, or bis(4-hydroxyphenyl) sulfone; - Novolac (this is a condensate of phenol or cresol with formaldehyde, in particular); - Aromatic amines, such as aniline, toluidine, 4-aminophenol, 4,4'-methylenediphenyldiamine, 4,4'-methylenediphenyldi(N-methyl)amine, 4,4'-[1,4-phenylenebis(1-methylethylidene)]bisaniline (bisaniline P), or 4,4'-[1,3-phenylenebis(1-methylethylidene)]bisaniline (bisaniline M).

[0060] Further preferred epoxy resins are aliphatic or alicyclic polyepoxides, particularly the following: - Saturated or unsaturated, branched or unbranched, cyclic or ring-opening, difunctional, trifunctional or tetrafunctional C2-C2 30 Alcohols, particularly ethylene glycol, propylene glycol, butylene glycol, hexanediol, octanediol, polypropylene glycol, dimethylolcyclohexane, neopentyl glycol, dibromo-neopentyl glycol, castor oil, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol or glycerol, or glycidyl ethers of alkoxylated glycerol or alkoxylated trimethylolpropane; - Liquid resins of hydrogenated bisphenol A, F, or A / F, or glycidylation reaction products of hydrogenated bisphenol A, F, or A / F; - N-glycidyl derivatives of amides or heterocyclic nitrogen bases, such as triglycidyl cyanurate or triglycidyl isocyanurate, or reaction products of epichlorohydrin and hydantoin.

[0061] Particularly preferred are aromatic diepoxides that are liquid at room temperature and have an epoxy equivalent weight in the range of 110-200 g / mol, preferably 150-200 g / mol, especially bisphenol A diglycidyl ether and / or bisphenol F diglycidyl ether (for example, commercially available from Olin, Huntsman, or Momentive). These liquid resins allow for rapid curing and high hardness.

[0062] Together with the liquid epoxy resin, the coating may contain, to a certain extent, a solid bisphenol A resin, or novolac glycidyl ether, or a reactive diluent.

[0063] Suitable reactive diluents include, in particular, the following: butanediol diglycidyl ether, hexanediol diglycidyl ether, diglycidyl ether or triglycidyl ether of trimethylolpropane, phenyl glycidyl ether, cresyl glycidyl ether, guaiacol glycidyl ether, 4-methoxyphenyl glycidyl ether, p-n-butylphenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, 4-nonylphenyl glycidyl ether, 4-dodecylphenyl glycidyl ether, cardanol glycidyl ether, benzyl glycidyl ether, allyl glycidyl ether, butyl glycidyl ether, hexyl glycidyl ether, 2-ethylhexyl glycidyl ether, or glycidyl ether of natural alcohol, for example, in particular, C8~C 10 or C 12 ~C 14 or C 13 ~C 15 alkyl glycidyl ether.

[0064] The epoxy resin coating preferably contains the amine of formula (I) described above and the carbon nanotubes described above in the amounts described above.

[0065] In addition to at least one amine of formula (I), the epoxy resin coating preferably contains at least one further amine, particularly at least one further amine having at least 4 aliphatic amine hydrogens.

[0066] Preferred amines having at least four aliphatic amine hydrogens include, in particular, the following: 2,2-dimethylpropane-1,3-diamine, pentane-1,3-diamine (DAMP), pentane-1,5-diamine, 1,5-diamino-2-methylpentane (MPMD), 2-butyl-2-ethylpentane-1,5-diamine (C11-neodiamine), hexane-1,6-diamine, 2,5-dimethylhexane-1,6-diamine, 2,2(4),4-trimethylhexane-1,6-diamine (TMD), heptane-1,7-diamine, octane-1,8-diamine, nonane-1,9-diamine, decane-1,10-diamine, undecane-1,11-diamine, dodecane-1,12-diamine, and 1-amino-3-aminomethyl-3,5,5-to Dimethylcyclohexane (IPDA), 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane, bis(4-amino-3-ethylcyclohexyl)methane, bis(4-amino-3,5-dimethylcyclohexyl)methane, bis(4-amino-3-ethyl-5-methylcyclohexyl)methane, 2(4)-methyl-1,3-diaminocyclohexane, 2,5(2,6)-bis(aminomethyl)bicyclo[2.2.1]heptane (NBDA), 3(4),8(9)-bis(aminomethyl)tricyclo[5.2.1.0 2,6] Decane, 1,4-diamino-2,2,6-trimethylcyclohexane (TMCDA), menthane-1,8-diamine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,3-bis(aminomethyl)benzene (MXDA), 1,4-bis(aminomethyl)benzene, bis(2-aminoethyl) ether, 3,6-dioxaoctane-1,8-diamine, 4,7-dioxadecane-1,10-diamine, 4,7-dioxadecane-2,9-diamine, 4,9 -Dioxadodecane-1,12-diamine, 5,8-dioxadodecane-3,10-diamine, 4,7,10-trioxatridecane-1,13-diamine or higher oligomers of these diamines, bis(3-aminopropyl)polytetrahydrofuran or other polytetrahydrofrangamines, polyoxyalkylenediamines or triamines, especially polyoxypropylenediamines or polyoxypropylenetriamines, for example, Jeffamine® D-230, Jeffam ine(registered trademark) D-400, or Jeffamine(registered trademark) T-403 (both manufactured by Huntsman), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), dipropylenetriamine (DPTA), N-(2-aminoethyl)propane-1,3-diamine (N3amine), N,N'-bis(3-aminopropyl)ethylenediamine (N4amine), N,N'-bis(3-aminopropyl N,N'-(3-aminopropyl)-2-methylpentane-1,5-diamine, N3-(3-aminopentyl)pentane-1,3-diamine, N5-(3-amino-1-ethylpropyl)-2-methylpentane-1,5-diamine, N,N'-bis(3-amino-1-ethylpropyl)-2-methylpentane-1,5-diamine, 3-(2-aminoethyl)aminopropylamine, bis(hexamethylene)triamine (BHMT), and adducts of these amines with epoxy resins.

[0067] Furthermore, the amine is preferably selected from the group consisting of the following: TMD, IPDA, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, bis(4-aminocyclohexyl)methane, 2(4)-methyl-1,3-diaminocyclohexane, MXDA, with an average molecular weight in the range of 200 to 500 g / mol. n Polyoxypropylenediamine having the following properties, with an average molecular weight M in the range of 300-500 g / mol n Adducts of polyoxypropylene triamines, BHMT, DETA, TETA, TEPA, PEHA, DPTA, N3 amine, N4 amine, IPDA, MXDA, DETA, TETA or TEPA with epoxy resin, and mixtures of two or more of the above amines.

[0068] Particularly preferred are: TMD, IPDA, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, MXDA, and an average molecular weight M in the range of 200-500 g / mol. n A polyoxypropylenediamine having, an adduct of IPDA and / or MXDA with an aromatic diepoxide, or a mixture of two or more of the above-mentioned amines.

[0069] Further preferred amines include: N-aminoethylpiperazine, 3-dimethylaminopropylamine (DMAPA), 3-(3-(dimethylamino)propylamino)propylamine (DMAPAPA), monoamines, polyamidoamines, especially mono- or poly-basic carboxylic acids or their esters or anhydrides, especially reaction products of dimer fatty acids with polyamines used in stoichiometric excess, especially DETA or TETA, Mannich bases, especially phenalkamines, i.e., reaction products of phenols, especially cardanols, with aldehydes, especially formaldehydes, and polyamines or aromatic polyamines, for example, especially 4,4'-, 2,4'- and / or 2,2'-diaminodiphenylmethane, 2,4(6)-tolylenediamine, 3,5-dimethylthio-2,4(6)-tolylenediamine, or 3,5-diethyl-2,4(6)-tolylenediamine.

[0070] Preferably, 5% to 50% of all amine hydrogens present in the epoxy resin coating are derived from the amine of formula (I), and there is also the presence of at least one further amine having at least four aliphatic amine hydrogens.

[0071] The further amine having at least four aliphatic amine hydrogens is preferably TMD, IPDA, 1,3-bis(aminomethyl)cyclohexane, MXDA, with an average molecular weight in the range of 200-500 g / mol. n A selection is made from the group consisting of polyoxypropylenediamines having the following properties. Particularly preferred is a combination of two or more of these further amines.

[0072] Suitable accelerators include: acids in particular or compounds that can be hydrolyzed to acids, especially organic carboxylic acids such as acetic acid, benzoic acid, salicylic acid, 2-nitrobenzoic acid, lactic acid, organic sulfonic acids such as methanesulfonic acid, p-toluenesulfonic acid, or 4-dodecylbenzenesulfonic acid, sulfonic acid esters, other organic or inorganic acids such as phosphoric acid, or mixtures of the above-mentioned acids and acid esters; nitrates such as calcium nitrate; tertiary amines such as 1,4-diazabicyclo[2.2.2]octane, benzyldimethylamine, α-methylbenzyldimethylamine, triethanolamine, dimethylaminopropylamine; imidazoles such as N-methylimidazole, N-vinylimidazole 1,2-dimethylimidazole, salts of such tertiary amines, quaternary ammonium salts, for example benzyltrimethylammonium chloride, especially amidine, for example especially 1,8-diazabicyclo[5.4.0]undes-7-ene, guanidine, for example especially 1,1,3,3-tetramethylguanidine, phenol, especially bisphenol, phenol resins, or Mannich bases, for example especially 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol, or phenol, polymers made from formaldehyde and N,N-dimethylpropane-1,3-diamine, phosphites, for example especially di- or tri-phenyl phosphite, or compounds having a mercapto group.

[0073] Preferred are acids, nitrates, tertiary amines, or Mannich bases, particularly salicylic acid, calcium nitrate, or 2,4,6-tris(dimethylaminomethyl)phenol, or combinations thereof of accelerators.

[0074] Suitable fillers include, in particular, the following: ground or precipitated calcium carbonate (optionally coated with fatty acids, especially stearate), barite, talc, quartz powder, silica sand, silicon carbide, iron mica, dolomite, wollastonite, kaolin, mica (potassium aluminum silicate), molecular sieves, aluminum oxide, zinc oxide, aluminum-doped zinc oxide, aluminum hydroxide, magnesium hydroxide, silica, cement, gypsum, fly ash, carbon black, graphite, metal powders such as aluminum, copper, iron, zinc, silver, or steel powder, PVC powder, or hollow beads.

[0075] Particularly preferred fillers for pigment-colored epoxy resin coatings are calcium carbonate, talc, quartz powder, silica sand, dolomite, wollastonite, or kaolin, especially calcium carbonate, quartz powder, silica sand, or combinations thereof. Since such fillers do not have excessively high specific gravity, they rarely settle during application and curing, making it possible to obtain a highly uniformly cured coating with particularly homogeneous electrical conductivity.

[0076] A preferred filler for transparent epoxy resin coatings is zinc oxide, particularly aluminum-doped zinc oxide, in small amounts ranging from 0.5% to 5% by weight, preferably 1% to 3% by weight, relative to the entire epoxy resin coating. Such amounts of zinc oxide can lighten the coating somewhat and counteract the slightly dark gray hue of small amounts of carbon nanotubes, while still maintaining good electrical conductivity, thus achieving high transparency with little darkening and without the need for background lightening. Such transparent epoxy resin coatings are also suitable as transparent sealants on all types of electrostatic dissipative floors. In particular, they are suitable as transparent sealants on surfaces on which conductive silica sand has been sprinkled, allowing good visibility of the silica sand and the underlying coating through the transparent sealant. Such surfaces are particularly slip-resistant and also meet high aesthetic requirements.

[0077] The transparent epoxy resin coating preferably contains less than 0.1% by weight of fillers or pigments other than carbon nanotubes and zinc oxide, and more preferably, it contains no such fillers or pigments at all.

[0078] Suitable thinners include, in particular, xylene, 2-methoxyethanol, dimethoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-isopropoxyethanol, 2-butoxyethanol, 2-phenoxyethanol, 2-benzyloxyethanol, benzyl alcohol, ethylene glycol, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, ethylene glycol diphenyl ether, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, its diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-butyl ether, propylene glycol butyl ether, propylene glycol phenyl ether, dipropylene Recall, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol di-n-butyl ether, 2,2,4-trimethylpentan-1,3-diol monoisobutyrate, diphenylmethane, diisopropylnaphthalene, mineral oil fractions, e.g., Solvesso® grade (manufactured by Exxon), alkylphenols, e.g., tert-butylphenol, nonylphenol, dodecylphenol, cardanol (from cashew nut shell oil, including 3-(8,11-pentadecadienyl)phenol), styrene phenols, bisphenols, aromatic hydrocarbon resins, especially those containing phenolic groups, alkoxylated phenols, especially ethoxylated or propoxylated phenols, especially 2-phenoxyethanol, adipates, sebacates, phthalates, benzoates, organophosphoric acids or sulfonic acid esters, or sulfonamides.

[0079] A preferred thinner has a boiling point higher than 200°C.

[0080] Benzyl alcohol is particularly preferred.

[0081] The epoxy resin coating preferably contains a thinner having a boiling point of less than 200°C in a low content, particularly less than 1% by weight.

[0082] The epoxy resin coating preferably contains only a small amount of thinner having a boiling point above 200°C, particularly less than 20% by weight, and preferably less than 15% by weight.

[0083] Suitable surface additives include, in particular, defoaming agents, defoaming agents, wetting agents, dispersants, leveling agents, or dispersed paraffin waxes. It is preferable that the epoxy resin coating contains a combination of such additives.

[0084] Suitable stabilizers are those that stabilize against UV light or heat.

[0085] The epoxy resin coating may optionally include further auxiliary agents and additives, particularly the following: - Pigments, especially titanium dioxide, iron oxide, or chromium(III) oxide, - Compounds having a mercapto group, particularly liquid mercaptan-terminated polysulfide polymers, mercaptan-terminated polyoxyalkylene ethers, mercaptan-terminated polyoxyalkylene derivatives, thiocarboxylic acid polyesters, 2,4,6-trimercapto-1,3,5-triazine, triethylene glycol dimercaptan, or ethanedithiol. - Further reactive diluents, particularly epoxidized soybean oil or linseed oil, compounds containing acetacetate groups, especially acetoacetylated polyols, butyrolactones, carbonates, aldehydes, isocyanates, or silicones having reactive groups. - Polymers, particularly polyamides, polysulfides, polyvinyl formal (PVF), polyvinyl butyral (PVB), polyurethane (PUR), polymers having carboxyl groups, polyamides, butadiene-acrylonitrile copolymers, styrene-acrylonitrile copolymers, butadiene-styrene copolymers, homopolymers or copolymers of unsaturated monomers, for example, particularly ethylene, propylene, butylene, isobutylene, isoprene, vinyl acetate, or alkyl (meth)acrylate, or chlorosulfonated polyethylene, fluorine-containing polymers, or sulfonamide-modified melamine. - Rheology modifiers, especially anti-settling agents, - Adhesion improvers, especially organoalkoxysilanes, - Flame retardant substances, especially polybrominated diphenyl oxide or diphenyl ether phosphates, for example, especially diphenyl cresyl phosphate, resorcinol bis(diphenyl phosphate), resorcinol diphosphate oligomer, tetraphenyl resorcinol diphosphite, ethylenediamine diphosphate, bisphenol A bis(diphenyl phosphate), tris(chloroethyl) phosphate, tris(chloropropyl) phosphate, tris(dichloroisopropyl) phosphate, tris[3-bromo- 2,2-Bis(bromomethyl)propyl phosphate, tetrabromobisphenol A, bis(2,3-dibromopropyl ether) of bisphenol A, brominated epoxy resin, ethylenebis(tetrabromophthalimide), ethylenebis(dibromonolbornanedicarboxyimide), 1,2-bis(tribromophenoxy)ethane, tris(2,3-dibromopropyl) isocyanurate, tribromophenol, hexabromocyclododecane, bis(hexachlorocyclopentadienone)cyclooctane, or chloroparaffin. - Further conductive materials, in particular doped mineral fillers, metal powders, carbon fibers, carbon black, graphite, or ionic liquids, - Further additives, especially film-forming aids or insecticides.

[0086] The epoxy resin coating preferably consists of at least two components, which are stored in separate containers and mixed together immediately before application.

[0087] The resin component includes at least a liquid epoxy resin and various further compounds containing epoxy groups.

[0088] The curing agent components include the amine of formula (I) and various other compounds that are reactive with epoxy groups.

[0089] Further components, particularly carbon nanotubes, can be present as components of the resin and / or as components of the curing agent. Carbon nanotubes dispersed in a liquid containing epoxy groups are a preferred component of the resin.

[0090] An epoxy resin coating containing the following is preferred: - A resin component comprising at least one liquid epoxy resin, carbon nanotubes, at least one defoaming agent, optionally pigments and fillers, and optionally at least one thinner, particularly benzyl alcohol, and - A curing agent component comprising at least one amine of formula (I), optionally a further amine, optionally at least one thinner, particularly benzyl alcohol, and optionally at least one accelerator.

[0091] The epoxy resin composition is preferably not water-based and contains only a very small amount of water, preferably less than 5% by weight, and especially less than 1% by weight. Such a coating is particularly robust with respect to moisture.

[0092] However, it is also possible for the epoxy resin coating to contain a larger amount of water. In particular, the resin component, the curing agent component, or both may be water-based.

[0093] Based on the entire coating, an epoxy resin coating including the following is particularly preferred: - 0.001% to 0.05% by weight of carbon nanotubes, - A thinner having a boiling point of less than 200°C, in an amount of less than 1% by weight, - Less than 5% by weight of water.

[0094] Such coatings offer good applicability, emit very few substances, and enable floor coatings with particularly high moisture resistance and good electrical conductivity.

[0095] In a preferred embodiment, the epoxy resin coating is pigment-colored and contains 20% to 70% by weight, particularly 30% to 60% by weight, of calcium carbonate, crushed quartz, silica sand, or a combination thereof, based on the entire coating.

[0096] Such coatings, in particular, enable robust floor coatings with decorative colors, where the filler rarely settles during application and curing, resulting in virtually no unevenness in the coating.

[0097] In a further preferred embodiment, the epoxy resin coating is transparent and, based on the entire composition, includes the following: - 0.001 wt% to 0.01 wt% carbon nanotubes, - 1% to 3% by weight of zinc oxide, especially aluminum-doped zinc oxide, and - In particular, fillers or pigments other than carbon nanotubes and zinc oxide in amounts of less than 0.1% by weight.

[0098] Such coatings enable high transparency and, in particular, achieve aesthetic effects when combined with conductive decorative silica sand.

[0099] In the epoxy resin coating, the ratio of the number of groups that react with epoxy groups to the number of epoxy groups is preferably in the range of 0.5 to 1.5, and more particularly in the range of 0.7 to 1.2.

[0100] The resin component and curing agent component of the epoxy resin composition are stored in separate containers. Suitable containers for storing the resin component or curing agent component are, in particular, buckets, hobocks, drums, pouches, or cartridges. "Storage stability" means that they can be stored for several months to a year or more before use without any change in their respective properties at a level relevant to their use. To use the epoxy resin coating, the components are mixed together immediately before or at the time of application. The mixing ratio between the resin component and the curing agent component is preferably selected such that the groups of the curing agent component that are reactive to epoxy groups are in an appropriate ratio to the epoxy groups of the resin component, as previously mentioned. The mixing ratio between the resin component and the curing agent component is typically in the range of (1:10) to (10:1), preferably (1:1) to (10:1), in parts by weight.

[0101] These components are mixed by an appropriate method, which may be continuous or batch. If application is not performed immediately after mixing, care must be taken to avoid a long delay between mixing and application, and to apply within the pot life. Mixing is carried out at ambient temperature (typically within the range of about 5 to 40°C, preferably about 10 to 35°C).

[0102] As soon as these two components are mixed, a chemical reaction to cure begins. The primary and secondary amino groups, as well as any other groups present that are reactive with the epoxy group, all react with the epoxy group, resulting in ring-opening (addition reaction). As a result of this reaction, the epoxy resin coating polymerizes, and thus hardens.

[0103] The curing process preferably proceeds at ambient temperature and typically lasts from several hours to several days. The duration depends on factors including temperature, the reactivity of its components, their stoichiometric ratios, and the presence of accelerators.

[0104] In its freshly mixed state, the epoxy resin coating has low viscosity. Viscosity at 20°C, 5 minutes after mixing, was measured using a cone-plate viscometer at a shear rate of 10s. -1 The measurement is preferably in the range of 100 to 4000 mPas, preferably 200 to 3000 mPas, and especially 300 to 2000 mPa·s.

[0105] The epoxy resin coating is applied to at least one substrate, the following substrates are particularly suitable: - Concrete, mortar, cement screed, fiber cement, brick, tile, gypsum, natural rocks such as granite or marble, or sand, especially conductive silica sand; - Repair compounds or flattening compounds based on PCC (polymer-modified cement mortar) or ECC (epoxy resin-modified cement mortar); - Metals or alloys, such as aluminum, iron, steel, copper, and other non-ferrous metals (including surface-finished metals or alloys, such as galvanized or chromium-plated metals); - Asphalt or bitumen; - Plastics such as rigid and flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resin, phenolic resin, PUR, POM, TPO, PE, PP, EPM, or EPDM (in any case, they may be untreated or treated by plasma, corona, or flame); - Fiber-reinforced plastics, such as carbon fiber reinforced plastics (CFRP), glass fiber reinforced plastics (GFRP), and sheet molding compounds (SMC); - Coated or painted substrates, in particular painted tiles, coated concrete, powder-coated metals or alloys; - Coated floors that have been overcoated with a coating, paint, or varnish, especially an additional layer of floor finishing material.

[0106] If necessary, the substrate may be pre-treated before application, particularly by physical and / or chemical cleaning methods, or by applying an activator or primer.

[0107] A freshly mixed epoxy resin coating is typically applied to the surface of the substrate in a layer thickness of approximately 0.1 to 5 mm at ambient temperature during its pot life. It is then poured over the substrate to be coated and spread and flattened using, for example, a doctor blade or rubber squeegee. It may also be applied using a brush or roller. Upon curing, a typically uniform, flat, glossy, non-stick, pigment-colored or transparent, high-hardness, and robust film is obtained, which exhibits good adhesion to a wide variety of substrates.

[0108] The present invention further provides a cured conductive epoxy resin coating obtained from the mixed epoxy resin coating.

[0109] After curing, the epoxy resin coating has an electrical conductivity within a range suitable for elements of an electrostatic dissipative floor system.

[0110] In particular, the epoxy resin coating, after curing with a layer thickness in the range of 0.3 to 3 mm, was measured according to DIN EN 61340-4-1, with a thickness of 5 × 10⁻⁶. 4 Over ohms and 10 9 It has a ground electrical resistance in the range smaller than ohms.

[0111] When the cured epoxy resin coating is transparent and has a layer thickness of 0.5 mm on glass, it has an absorption of 0.7 or less, preferably 0.6 or less, and particularly 0.5 or less at 665 nm, as measured by UV-vis spectroscopy. Such a coating is also suitable as a transparent sealant, particularly on electrostatic dissipative floors, especially on floors on which conductive silica sand is scattered, while maintaining good color visibility, sand structure, and achieving a highly aesthetic surface.

[0112] The epoxy resin coating of the present invention is preferably used as an element of an electrostatic dissipative floor system. Such floor systems are installed in manufacturing halls or rooms where problems would arise if electrostatic discharge were not controlled. These are rooms in particular where electronic components are manufactured, stored, or used, or where highly sensitive measuring systems are operated, or where flammable liquids or explosives are handled or stored, especially rooms with low humidity and particularly low airborne particulate matter, such as clean rooms, radiation facilities, or operating rooms.

[0113] Therefore, the present invention also provides an electrostatic dissipative floor system comprising the following, in order from the bottom to the top: (i) at least one substrate, (ii) Optionally, at least one epoxy resin primer, (iii) at least one grounded conductive system, (iv) at least one conductive epoxy resin coating (as described above) (v) Optionally, at least one dispersed filler, and (vi) Optionally, at least one type of sealing material.

[0114] The electrostatic dissipation floor system is preferably measured according to DIN EN 61340-4-1, with a value of 5 × 10⁻⁶. 4 Over ohms and 10 9 It has a total grounding electrical resistance in a range smaller than ohms.

[0115] Suitable substrates (i) are repair compounds or leveling compounds based on concrete (optionally pre-treated by grinding, sandblasting or shot blasting), mortar, cement screed, fiber cement, brick, tile, gypsum, natural rock such as granite or marble, asphalt, or PCC (polymer-modified cement mortar) or ECC (epoxy resin-modified cement mortar). Preferably, concrete, mortar, or cement screed.

[0116] The substrate is preferably coated with at least one epoxy resin primer (ii). This primer is preferably low viscosity and contains little to no filler. It particularly helps to solidify the substrate, closing all pores and ensuring good adhesion between the substrate and any further layers. The primer is typically applied to the substrate using a brush, roller, or rubber squeegee. The application rate is typically 0.2–0.5 kg / m². 2 This is carried out in one or more layers in quantities within the specified range. Examples of commercially available products suitable for this purpose include: Sikafloor(registered trademark)-150, Sikafloor(registered trademark)-151, Sikafloor(registered trademark)-160, or Sikafloor(registered trademark)-161 (all manufactured by Sika).

[0117] If the substrate is not flat, it can be made flat by applying a primer and then troweling the surface with an epoxy resin composition filled with sand.

[0118] The grounded conductive system (iii) is installed on a substrate that has been optionally primed and optionally planarized. For grounding, it is preferable to drill holes in the floor and firmly drive metal screws into them. Preferably, a copper wire mesh or copper ribbon is placed on the screws and brought into contact with the screws, for example, using a metal washer placed on top of it. Apparatus for this purpose and accurate instructions for installation are available, for example, from the commercially available Sikafloor® conductive set (manufactured by Sika).

[0119] Regarding the separation between the copper wire or copper ribbon and the grounding screw, a coating of type (iv) (called a conductive film) is further applied to this equipment to ensure conductivity between the copper wire or copper ribbon. Suitable conductive films are particularly high-conductivity epoxy resin coatings, such as Sikafloor®-220W Conductive (manufactured by Sika).

[0120] The conductive system preferably includes at least a grounded copper wire or a grounded copper ribbon, and optionally has contact with them and 10 4 It includes at least one conductive foil having an electrical resistance of less than ohms.

[0121] Next, a conductive epoxy resin coating (iv) containing at least carbon nanotubes and at least one amine of formula (I) is applied to the conductive system and cured as described above. The epoxy resin coating (iv) may be transparent or pigment-colored as described above. It is applied to the conductive system in one or more layers, particularly with a layer thickness in the range of 0.1 to 5 mm, preferably 0.2 to 3 mm. It is applied at a rate of 0.2 to 3 kg / m 2 Preferably 0.3 to 2.5 kg / m 2 It is preferable to apply it in a single layer within that range.

[0122] The conductive epoxy resin coating may be filled with a filler (v), which is spread during the pot life. Preferred fillers are crushed quartz and / or particularly silica sand. The properties of the filler may be such that most of it sinks into the coating and hardens the epoxy resin coating, or it may be such that an excess of sand is spread on top, hardened, and then the excess sand is removed to obtain a rough surface with sand.

[0123] It is preferable to use at least one type of conductive silica sand to create a rough surface by scattering sand.

[0124] Suitable conductive silica sand is coated with a conductive synthetic resin and, in particular, has a particle size in the range of 0.1 to 1.3 mm. Such silica sand is commercially available, for example, as Granucol® Conduct 2.0 (manufactured by Dorfner).

[0125] At least one sealant (vi) is optionally applied to a conductive epoxy resin coating on which a filler has already been sprayed. Particularly suitable for this purpose is a transparent, conductive epoxy resin coating containing carbon nanotubes and at least one amine of formula (I), and preferably in addition thereto, zinc oxide, particularly aluminum-doped zinc oxide.

[0126] Especially 0.1-1 kg / m 2 Preferably 0.2 to 0.7 kg / m 2 Apply the sealant in an amount within this range.

[0127] In a preferred embodiment of the floor system, its conductive epoxy resin coating (iv) is pigment-colored and has a layer thickness in the range of 0.1 to 5 mm, particularly 0.2 to 3 mm. In this case, it is preferable that no excess filler or sealant remains on the surface of the floor system. Therefore, it is preferable that the pigment-colored epoxy resin coating (iv) forms the uppermost layer of the floor system. In order to meet high aesthetic requirements, it is particularly important in this case that this surface has good degassability and is therefore especially flat.

[0128] In this embodiment, the electrical conductivity of the epoxy resin coating (iv) is sufficiently reliable and good, so a conductive film, such as Sikafloor®-220W Conductive (manufactured by Sika), can be omitted from the grounded conductive system (iii). This means that the entire operation, including the waiting time for the conductive film to cure, can be omitted, which is particularly advantageous.

[0129] In this embodiment, it is preferable to apply the pigment-colored conductive epoxy resin coating (iv) directly to at least one grounded copper wire or at least one grounded copper ribbon, without a conductive film in between.

[0130] In a further preferred embodiment of the present invention, an excess of conductive silica sand is sprinkled onto a conductive epoxy resin coating (iv) and covered with a transparent sealant. In this case, the epoxy resin coating (iv) is preferably present in a layer thickness in the range of 0.3 to 1 mm. It is preferably transparent and preferably contains zinc oxide, particularly aluminum-doped zinc oxide. The transparent sealant is preferably similar to the conductive epoxy resin coating and preferably contains carbon nanotubes and at least one type of zinc oxide.

[0131] The floor system of the present invention is preferably part of a building or a room within a building. In particular, the floor system can be located anywhere where uncontrolled discharges could cause damage. These include rooms where electronic components are manufactured, stored, or used, or where highly sensitive measuring systems are operated, or where flammable liquids or explosives are handled or stored, especially rooms with low humidity and particularly low airborne particulate matter, such as clean rooms, radiation facilities, or operating rooms. [Examples]

[0132] The following examples illustrate the working procedures, which are intended to further illustrate the described invention. Needless to say, the invention is not limited to the embodiments described in these working procedures.

[0133] "AHEW" represents the amine hydrogen equivalent.

[0134] "EEW" represents the epoxy equivalent weight.

[0135] "Standard climatic conditions (SCC)" refer to a temperature of 23±1℃ and relative atmospheric humidity of 50±5%.

[0136] Unless otherwise specified, the chemicals used are from Sigma-Aldrich Chemie GmbH.

[0137] Substances used and their abbreviations: CNT Dispersion 10%: A dispersion of 10% by weight of single-walled carbon nanotubes in alkyl glycidyl ether (EEW ​​= 266 g / mol) (Tuball® Matrix Beta 207, manufactured by OCSiAl). Araldite(registered trademark) GY 250: Bisphenol A diglycidyl ether, EEW = 187 g / mol (manufactured by Huntsman) Araldite® DY-P: p-tert-butylphenyl glycidyl ether, EEW = 225 g / mol (Huntsman) Araldite® DY-H: Hexanediol diglycidyl ether, EEW = 147 g / mol (Huntsman) Chalk: Omyacarb (registered trademark) 10 GU (made by Omya) Al-doped ZnO: Aluminum-doped zinc oxide (ZnO-23K, manufactured by Itochu) B-EDA: N-benzylethane-1,2-diamine, AHEW = 50.1 g / eq, prepared as follows. IPDA: 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, AHEW = 42.6 g / eq (Vestamin® IPD, manufactured by Evonik) MXDA: 1,3-bis(aminomethyl)benzene, AHEW = 34g / equiv. (Manufactured by Mitsubishi Gas Chemical Co., Ltd.) TMD: 2,2(4),4-trimethylhexamethylenediamine, AHEW = 39.6g / equiv. (Vestamin® TMD, manufactured by Evonik) D-230: Polyoxypropylenediamine, average molecular weight = 230 g / mol, AHEW = 60 g / mol (Jeffamine® D-230, manufactured by Huntsman) Adduct A1: IPDA, MXDA and Araldite® GY 250 adduct, in benzyl alcohol, AHEW = 231 g / eq, prepared as follows. Adduct B1: Adduct of B-EDA and Araldite® GY 250, AHEW = 116.3 g / eq, prepared as follows. Ancamine® K54: 2,4,6-Tris(dimethylaminomethyl)phenol (manufactured by Air Products) Sikafloor(registered trademark)-150: 2-component epoxy resin primer (manufactured by Sika) Sikafloor(registered trademark)-151: Two-component epoxy resin primer (manufactured by Sika) Sikafloor(registered trademark)-220W Conductive: 2-component, water-based, highly conductive, black epoxy resin coating Conductive silica sand: Synthetic resin-coated conductive silica sand, 0.3-0.8 mm (Granucol® Conduct 2.0, manufactured by Dorfner)

[0138] N-benzylethane-1,2-diamine (B-EDA): An initial charge of 180.3 g (3 mol) of ethane-1,2-diamine was mixed at room temperature with a solution of 106.0 g (1 mol) of benzaldehyde in 1200 mL of isopropanol, and stirred for 2 hours. The mixture was then hydrogenated in a continuous hydrogenator containing a stationary bed Pd / C catalyst at 80°C, a hydrogen pressure of 80 bar, and a flow rate of 5 mL / min. The hydrogenated solution was concentrated on a rotary evaporator at 65°C to remove unreacted ethane-1,2-diamine, water, and isopropanol. The resulting reaction mixture was purified by distillation under reduced pressure at 80°C. This yielded a colorless liquid containing N-benzylethane-1,2-diamine (content exceeding 97% as measured by GC).

[0139] Adduct A1: 57.3 g of IPDA, 42.5 g of MXDA, and 318.8 g of benzyl alcohol were heated to 80°C, and 81.3 g of Araldite® GY 250 was gradually added while stirring well, maintaining the temperature of the reaction mixture between 70°C and 90°C. A clear, pale yellow liquid with a viscosity of 45 mPa·s at 20°C was obtained.

[0140] Adduct B1: 55.0 g of N-benzylethane-1,2-diamine (B-EDA) was heated to 80°C, and 45.0 g of Araldite® GY 250 was gradually added while stirring well, maintaining the temperature of the reaction mixture between 70°C and 90°C. A clear, pale yellow liquid with a viscosity of 262 mPa·s at 20°C was obtained.

[0141] The viscosity of these adducts was measured as described in Example 1.

[0142] Preparation of conductive epoxy resin coatings: Examples 1-3 (Light gray pigment-colored coating): For these examples, the resin components were prepared by mixing the following components using a centrifugal mixer (SpeedMixer® DAC 150, manufactured by FlackTek Inc.), and stored away from moisture. 125.9 parts by weight of Araldite® GY 250, 25.2 parts by weight of Araldite® DY-P, 11.5 parts by weight of Araldite(registered trademark) DY-H, 0.27 parts by weight of CNT dispersion 10%, 231.0 parts by weight of chalk, 12.7 parts by weight of benzyl alcohol, 5.6 parts by weight of additives / defoaming agent, 45.8 parts by weight of a light gray pigment paste.

[0143] In each example, the curing agent components shown in Table 1 were mixed in the amounts (units, parts by weight) indicated by a centrifugal mixer and stored away from moisture.

[0144] Next, these two components were processed using a centrifugal mixer to form a homogeneous liquid, which was immediately tested in the following manner: Viscosity was measured using a cone-plate viscometer 5 minutes after mixing the resin and hardener components, at a shear rate of 10s. -1 The measurement was taken at a temperature of 20°C. The gelation time was determined by moving approximately 3g of a freshly mixed substance with a spatula at regular intervals under standard climate conditions until the substance gelled. Shore D hardness was measured according to DIN 53505, using two cylindrical test specimens (diameter: 20 mm, thickness: 5 mm) stored under standard climatic conditions of 8°C and 80% relative humidity. Hardness was measured after 1 day, 2 days, and 7 days.

[0145] Particleboard, 0.3 kg / m 2 The material was primed with Sikafloor(registered trademark)-150, stored for 24 hours under standard climatic conditions, and then treated with 0.1 kg / m². 2 The boards were coated with Sikafloor®-220W Conductive and stored for a further 24 hours under standard climate conditions. Each board was coated with 1.3 kg / m². 2 The epoxy resin coating was applied to the boat, distributed using a squeegee, and degassed while still in liquid state by rolling with a spiked roller. Leveling and degassing properties were then observed. Leveling was described as "excellent" when the liquid coating was quickly flattened with only a few passes of the squeegee and could be easily applied to corners. Leveling was described as "OK" when a significantly larger number of squeegee passes were required to distribute the liquid coating to corners, and then it gradually flattened. Degassing was described as "good" or "excellent" when, during rolling with the spiked roller, the finely dispersed air bubbles connected to form larger bubbles that reliably burst on the surface, and little or no further bubbles rose after rolling with the spiked roller. Even after rolling with spiked rollers, further finely dispersed air bubbles would rise and remain on the surface of the curing coating, causing its viscosity to increase and eventually gel. When this resulted in a slightly uneven, not perfectly flat surface, the degassing was described as "incomplete."

[0146] The appearance of the coated particleboard was evaluated after a 7-day curing period. A "good" surface was defined as glossy, non-sticky, and free from streaks or cloudiness. A "flat" surface was defined as a smooth surface free from unevenness or craters.

[0147] The grounding electrical resistance was measured at eight points on the coated particleboard from Example 1 after a curing time of 7 days under standard climatic conditions, in accordance with DIN EN 61340-4-1.

[0148] Those results are shown in Table 1.

[0149] Items marked with (Ref.) are comparative examples.

[0150] [Table 1]

[0151] Examples 4 and 5 (Transparent coating or sealing): For these examples, the resin components were prepared by mixing the following components using a centrifugal mixer and stored away from moisture. 185.6 parts by weight of Araldite® GY 250, 0.04 parts by weight of CNT dispersion 10%, 4.2 parts by weight of Al-doped ZnO, 4.8 parts by weight of additives / defoaming agent, 15.4 parts by weight of benzyl alcohol.

[0152] In each example, the curing agent components shown in Table 2 were mixed in the amounts (units, parts by weight) indicated by a centrifugal mixer and stored away from moisture.

[0153] Next, these two components were processed using a centrifugal mixer to form a homogeneous liquid, which was then tested in the following manner:

[0154] Viscosity, gelation time, and Shore D were tested as described in Example 1.

[0155] Particleboard, 0.3 kg / m 2 The material was primed with Sikafloor(registered trademark)-150, stored for 24 hours under standard climatic conditions, and then treated with 0.1 kg / m². 2 The boards were coated with Sikafloor®-220W Conductive and stored for a further 24 hours under standard climate conditions. 0.5 kg / m 2 Each sample was applied to the boat coated in the same manner, distributed using a squeegee, and rolled using a nylon roller while still in a liquid state. The leveling and degassing properties were then evaluated as described in Example 1.

[0156] Transparency was evaluated by coating a glass plate with a 500 μm thick film layer and storing it for 7 days under standard climate conditions. The glass plate was then placed on printed newspaper, and the legibility of the newspaper print through the coated glass plate was evaluated. Transparency was described as "high" when the print was clearly and sharply legible. Transparency was described as "average" when the print was good but blurry.

[0157] As a further measure of transparency, absorption was measured using UV-vis spectroscopy. For this purpose, absorption at 665 nm (red) was measured on coated glass plates using a UV-vis system (Cary 60, manufactured by Agilent Technologies) to evaluate transparency.

[0158] The appearance and electrical resistance were determined for the coated particleboard as described in Example 1.

[0159] Those results are shown in Table 2.

[0160] Items marked with (Ref.) are comparative examples.

[0161] [Table 2]

[0162] Manufacturing of electrostatic dissipative floor systems: Example 6: Area 55m 2 An electrostatic dissipative floor system was installed on a polished indoor concrete floor. During the installation, the temperature was 25°C to 30°C and the humidity was 35% to 40%.

[0163] First, a layer of Sikafloor(registered trademark)-151 as a primer was applied at a rate of 0.4 kg / m². 2 The mixture was rolled out in that quantity and left to harden for 24 hours.

[0164] Next, the grounding points and copper ribbons from the Sikafloor® conductive set were attached to the floor and prepared according to the instructions for use.

[0165] Next, the conductive epoxy resin coating from Example 1 was applied at a rate of 2.0 kg / m². 2 The epoxy resin coating was applied in a specific ratio, distributed using a rubber squeegee, and rolled using a spiked roller. The resulting epoxy resin coating exhibited excellent leveling and extremely good degassing properties. The resulting gray pigment-colored surface was flat, high-hardness, high-gloss, non-stick, and free from streaks and cloudiness.

[0166] The grounding electrical resistance of the completed floor system was measured at 30 points according to DIN EN 61340-4-1. The range of the measured values ​​is shown in Table 3.

[0167] Example 7: Area 55m 2An electrostatic dissipative floor system was installed on a polished indoor concrete floor. During installation, the temperature of the substrate was 14-17°C, the ambient temperature was 13-19°C, and the humidity was 49-66%.

[0168] First, a layer of Sikafloor(registered trademark)-151 as a primer was applied at a rate of 0.4 kg / m². 2 The mixture was rolled out in that quantity and left to harden for 24 hours.

[0169] Next, the grounding points and copper ribbon from the Sikafloor® conductive set are attached to the floor and prepared according to the instructions for use. Subsequently, the Sikafloor®-220W Conductive coating is applied as a conductive film at a rate of 0.1 kg / m². 2 It was rolled up in that quantity.

[0170] After a 24-hour curing time, the transparent, conductive epoxy resin coating from Example 4 was applied at a rate of 0.5 kg / m². 2 It was applied in the specified quantity. For this purpose, the raw material was poured, distributed using a rubber squeegee, and then rolled using a roller.

[0171] Within 30 minutes of application, apply 3 kg / m². 2 An excess amount of conductive silica sand was sprinkled onto this layer. After a 24-hour curing time, the excess sand was removed by means of a brush and a vacuum cleaner.

[0172] Next, the sand-treated surface was coated with a conductive epoxy resin coating from Example 4 using a rubber squeegee at a rate of 0.4 kg / m². 2 The material was distributed in the specified quantities, and then rolled using a structured roller to produce a transparent sealing material.

[0173] The sealant exhibited good distribution properties on the sand-treated surface, and subsequent rolling resulted in a flat surface free of streaks, bubbles, craters, or other irregularities. After curing, the floor system had a highly aesthetic, flat, light gray shimmer, hard, tack-free, and transparent surface, thereby allowing good visibility of the sand's color.

[0174] The grounding electrical resistance of the completed floor system was measured at 30 points according to DIN EN 61340-4-1. The range of the measured values ​​is shown in Table 3.

[0175] [Table 3]

Claims

1. The use of a combination of carbon nanotubes and at least one amine of the following formula (I) for the production of a conductive epoxy resin coating, wherein: Z-NH-A-NH-CH ２ -Y (I) (In the formula, A is a divalent C containing any one or more nitrogen atoms or ether groups. ２ ~C １５ The alkylene, cycloalkylene, or arylalkylene group is Z is H, or -CH ２ -Y is, Y is H or C １ ~C １２ (The group is an alkyl, cycloalkyl, arylalkyl, or aryl group.) Here, the amine of formula (I) contains a total of at least eight carbon atoms, use.

2. The use according to claim 1, characterized in that the carbon nanotubes are present in an amount of 0.001% to 0.1% by weight, particularly 0.001% to 0.05% by weight, based on the entire epoxy resin coating.

3. The use according to claim 1 or 2, characterized in that A is 1,2-ethylene, Z is H, and Y is phenyl.

4. The use according to any one of claims 1 to 3, characterized in that the amine of formula (I) is present in such an amount that at least 5% of all amine hydrogens present in the epoxy resin coating originate from the amine of formula (I).

5. A conductive epoxy resin coating obtained from the use described in any one of claims 1 to 4, comprising the following: - At least one type of liquid epoxy resin, - At least one amine of formula (I), - Carbon nanotubes, and - At least one further component selected from the group consisting of further amines, accelerators, fillers, thinners, surfactants, and stabilizers.

6. The epoxy resin coating according to claim 5, characterized in that 5% to 50% of all present amine hydrogens are derived from the amine of formula (I), and at least one further amine having at least four aliphatic amine hydrogens is present.

7. The epoxy resin coating according to claim 5 or 6, characterized in that it contains less than 5% by weight of water based on the entire coating.

8. Based on the entire coating, the epoxy resin coating according to any one of claims 5 to 7 is characterized by including the following: - 0.001% to 0.05% by weight of carbon nanotubes, - A thinner having a boiling point of less than 200°C and less than 1% by weight, - Less than 5% by weight of water.

9. The epoxy resin coating according to any one of claims 5 to 8, characterized in that it is pigment-colored and contains 20% to 70% by weight of calcium carbonate, crushed quartz, silica sand, or a combination thereof, based on the entire coating.

10. An epoxy resin coating according to any one of claims 5 to 8, characterized in that it is transparent and, based on the entire coating, includes the following: - 0.001% by weight to 0.01% by weight of carbon nanotubes, - 1% to 3% by weight of zinc oxide, especially aluminum-doped zinc oxide, and - In particular, fillers or pigments other than carbon nanotubes and zinc oxide, in amounts of less than 0.1% by weight.

11. A cured conductive epoxy resin coating obtained from a mixed epoxy resin coating according to any one of claims 5 to 10.

12. An electrostatic dissipative floor system comprising the following from the lower to the upper level: (i) at least one type of substrate, (ii) Optionally, at least one epoxy resin primer, (iii) at least one grounded conductive system, (iv) At least one conductive epoxy resin coating according to claim 11, (v) Optionally, at least one dispersed filler, and (vi) Optionally, at least one type of sealing material.

13. The grounding electrical resistance determined according to DIN EN 61340-4-1 is 5 × 10 ４ Over ohms and 10 ９ The floor system according to claim 12, characterized in that it is in a range smaller than ohms.

14. The conductive system includes at least a grounded copper wire or a grounded copper ribbon, and optionally includes at least one conductive foil in contact with them and having an electrical resistance of less than 10 ４ ohms, the floor system according to claim 12 or 13.

15. The floor system according to any one of claims 12 to 14, characterized in that the conductive epoxy resin coating is pigment-colored and has a layer thickness in the range of 0.1 to 5 mm, particularly 0.2 to 3 mm.

16. The floor system according to claim 15, characterized in that the conductive epoxy resin coating is applied directly to at least one grounded copper wire or at least one grounded copper ribbon, and there is no conductive foil between them.

17. The floor system according to any one of claims 12 to 14, characterized in that an excess of conductive silica sand is scattered on the conductive epoxy resin coating and covered with a transparent sealant.

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