Novel polythiophene / polyanion compositions.

Abstract

A conductive polymer dispersion comprising: (a) at least one oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula (I) with at least one monomer according to formula (II), wherein A is a substituted or unsubstituted C 1 -C 5 R represents a linear or branched, substituted or unsubstituted C 1 -C 18 -Alkyl group, substituted or unsubstituted C 5 -C 12 -Cycloalkyl group, substituted or unsubstituted C 6 -C 14 -aryl group, substituted or unsubstituted C 7 -C 18 s represents an integer from 0 to 8; Ra and Rb are each independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group; and (b) a polymeric polyanion, at least 75 mol % of the monomer units of the polymeric polyanion having a functional group selected from the group consisting of sulfonic acid or a salt thereof, phosphonic acid or a salt thereof, phosphoric acid ester or a salt thereof, sulfuric acid ester or a salt thereof, and carboxylic acid or a salt thereof, wherein the weight ratio of the monomer according to formula (I) to the monomer according to formula (II) is 25 / 75 to 75 / 25. [Formula 1] TIFF2025517439000020.tif46170 [C2] TIFF2025517439000021.tif37170

Description

[Technical field]

[0001] The present invention relates to novel polythiophene / polyanion compositions and their use in various applications, such as, for example, as antistatic layers. [Background technology]

[0002] Antistatic coatings are applied to poorly conductive surfaces, such as plastic films or paper, to reduce or prevent the build-up of static electricity. Such coatings are important in several electronic applications, where static electricity can be damaging to the devices in which they are used. For example, antistatic packaging trays and in display applications, such as liquid crystal displays (LCDs) or organic light-emitting diodes (OLEDs), antistatic coatings are used to prevent static discharge.

[0003] Conductive polymers are used to prepare antistatic coatings because the conductivity and processability of the antistatic coating can be tailored to suit various coating techniques and substrates. Among the conductive polymers, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is frequently used, which is a conductive polymer that can be prepared as an aqueous dispersion and is easily processed by conventional coating techniques.

[0004] PEDOT:PSS formulations are developed to, for example, optimize coating properties, enhance adhesion to the substrate, or improve the stability of the coating layer. Organic solvents, such as methanol, ethanol, or isopropanol, are often added. Such solvents can, for example, improve the dispersibility of other components in the formulation. However, it has been observed that the addition of organic solvents to aqueous dispersions of PEDOT:PSS can reduce the gelling stability of the dispersion. Viscosity increase or gel formation can seriously impair the coatability of the formulation.

[0005] Therefore, conductive polymer dispersions with high gelation stability upon addition of organic solvents are important to enable the development of new antistatic coating formulations.

[0006] Patent Document 1 (Panasonic) discloses a thiophene copolymer of 3,4-ethylenedioxythiophene (EDOT) and 3,4-dialkylthiophene. The amount of 3,4-dialkylthiophene in the copolymer is 0.005 to 13% by weight based on the total weight of the thiophene copolymer. The thiophene copolymer is used in a capacitor.

[0007] Copolymerization of EDOT and 3,4-dimethoxythiophene (90 / 10 ratio) in the presence of PSS is described in US Pat. No. 5,399,633 (Eternal Materials Co Ltd). Particle size of aqueous polymer dispersions and surface resistivity of coated films are disclosed. In another patent by Eternal Materials Co Ltd, copolymers with different weight ratios are prepared in ethanolic iron(III) p-toluenesulfonate solution (US Pat. No. 5,499,633). Polymer capacitors are prepared in both patents, but neither describes the gelation behavior of the conductive polymer dispersions in the presence of organic solvents.

[0008] Patent Document 4 (Tosoh) discloses copolymers of EDOT and 3,4-dialkoxythiophene monomers in molar ratios of 99.99 / 0.01 to 80 / 20. The thermal stability of the coated film is determined by measuring the surface resistance before and after subjecting it to a heating test. A composition for overcurrent protection devices is developed, and there is no mention of gelation stability when an organic solvent is added. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] WO2021 / 172199 [Patent Document 2] US9613757 [Patent Document 3] US9036333 [Patent Document 4] JP2012255049 Summary of the Invention

[0010] An object of the present invention is to provide a conductive polymer dispersion having improved gelation stability upon addition of an organic solvent.

[0011] The object of the present invention is achieved by a dispersion as defined in claim 1.

[0012] Further objects of the present invention will become apparent from the following description of the present specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] definition The term "monofunctional", for example when referring to a monofunctional polymerizable compound, means that the polymerizable compound has one polymerizable group.

[0014] The term "difunctional", for example when referring to a difunctional polymerizable compound, means that the polymerizable compound has two polymerizable groups.

[0015] The term "multifunctional," for example when referring to a multifunctional polymerizable compound, means that the polymerizable compound has more than two polymerizable groups.

[0016] The term "alkyl" refers to all possible variations of the alkyl group of each number of carbon atoms, namely methyl, ethyl, n-propyl and isopropyl for those with 3 carbon atoms, n-butyl, isobutyl and tertiary butyl for those with 4 carbon atoms, n-pentyl, 1,1-dimethyl-propyl, 2,2-dimethylpropyl and 2-methyl-butyl for those with 5 carbon atoms, etc.

[0017] Unless otherwise specified, the substituted or unsubstituted alkyl group is preferably 1 -C 6 -alkyl group.

[0018] Unless otherwise specified, the substituted or unsubstituted alkenyl group is preferably 2 -C 6 -alkenyl group.

[0019] Unless otherwise specified, the substituted or unsubstituted alkynyl group is preferably 2 -C 6 -alkynyl group.

[0020] Unless otherwise specified, the substituted or unsubstituted alkaryl group preferably has one, two, three or more C 1 -C 6 -alkyl group is a phenyl or naphthyl group.

[0021] Unless otherwise specified, the substituted or unsubstituted aralkyl group is preferably a C aryl group having a phenyl or naphthyl group. 7 -C 20 -alkyl group.

[0022] Unless otherwise specified, the substituted or unsubstituted aryl group is preferably a phenyl group or a naphthyl group.

[0023] Unless otherwise specified, a substituted or unsubstituted heteroaryl group is preferably a five- or six-membered ring substituted with one, two, or three oxygen, nitrogen, sulfur, or selenium atoms, or combinations thereof.

[0024] Unless otherwise specified, the substituted or unsubstituted alkylene group is preferably 1 -C 6 -alkylene group.

[0025] The term "substituted," for example when referring to a substituted alkyl group, means that the alkyl group can be substituted with atoms other than those normally present in such a group (i.e., carbon and hydrogen). For example, a substituted alkyl group can include a halogen atom or a thiol group. An unsubstituted alkyl group contains only carbon and hydrogen atoms.

[0026] Unless otherwise specified, substituted alkyl, alkenyl, alkynyl, aralkyl, alkaryl, aryl, and heteroaryl groups are preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tertiary butyl, esters, amides, amines, ethers, thioethers, ketones, aldehydes, sulfoxides, sulfones, sulfonate esters, sulfonamides, -Cl, -Br, -I, -OH, -SH, -CN, and -NO. 2 is replaced by one or more members selected from the group consisting of:

[0027] Conductive polymer dispersion A dispersion that includes a conductive polymer is referred to herein as a conductive polymer dispersion.

[0028] The conductive dispersion according to the present invention comprises a conductive polymer and a polyanion, both of which are as described below.

[0029] The dispersion medium of the conductive polymer dispersion is preferably selected from water, a water-soluble organic solvent, or a mixture thereof. Suitable organic solvents are protic organic solvents, such as alcohols or acids. The dispersion medium is preferably water.

[0030] The conductive polymer dispersion may contain other ingredients, such as a dispersing agent.

[0031] The conductive polymer dispersion is preferably prepared as described below.

[0032] The median particle size (d 50 ) is preferably 1 to 150 nm, more preferably 2 to 50 nm, and most preferably 5 to 40 nm. 50 The particle size is preferably measured by laser diffraction methods.

[0033] Conductive Polymers The conductive polymer according to the invention is an oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula I with at least one monomer according to formula II, [ka] Formula I [ka] Formula II During the ceremony, A is a substituted or unsubstituted C 1 -C 5 represents an alkylene bridge; R is a linear or branched, substituted or unsubstituted C 1 -C 18 -Alkyl group, substituted or unsubstituted C 5 -C 12 -Cycloalkyl group, substituted or unsubstituted C 6 -C 14 -aryl group, substituted or unsubstituted C 7 -C 18 -Aralkyl group, substituted or unsubstituted C 1 -C 4 - selected from the group consisting of hydroxyalkyl groups, and hydroxyl groups; s represents an integer from 0 to 8; Ra and Rb are independently selected from the group consisting of hydrogen, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkenyl groups, substituted or unsubstituted alkynyl groups, substituted or unsubstituted aralkyl groups, substituted or unsubstituted alkaryl groups, and substituted or unsubstituted aryl or heteroaryl groups; It is characterized in that the weight ratio of the monomer according to formula I to the monomer according to formula II is from 75 / 25 to 25 / 75, preferably from 70 / 30 to 40 / 60, more preferably from 65 / 35 to 50 / 50.

[0034] Monomers according to formula I The conductive polymer according to the invention is an oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula I, [ka] Formula I During the ceremony A is a substituted or unsubstituted C 1 -C 5 represents an alkylene bridge; R is a linear or branched, substituted or unsubstituted C 1 -C 18 -Alkyl group, substituted or unsubstituted C 5 -C 12 -Cycloalkyl group, substituted or unsubstituted C 6 -C 14 -aryl group, substituted or unsubstituted C 7 -C 18 -Aralkyl group, substituted or unsubstituted C 1 -C 4 - selected from the group consisting of hydroxyalkyl groups, and hydroxyl groups; s represents an integer of 0 to 8.

[0035] C 1 -C 5 The term alkylene bridge as used in Formula I means an alkylene bridge containing from 1 to 5 carbon atoms.

[0036] C 1 -C 5 The alkylene bridge is preferably methylene, ethylene, n-propylene, n-butylene, or n-pentylene.

[0037] C 1 -C 18 - As alkyl radicals, linear or branched C 1 -C18 -alkyl radicals, such as methyl, ethyl, n- or isopropyl, n-, iso-, sec- or tert-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-ethylpropyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-hexadecyl or n-octadecyl.

[0038] C 5 -C 12 -Cycloalkyl radical represents for example cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl or cyclodecyl.

[0039] C 6 -C 14 -aryl radical represents, for example, phenyl or naphthyl.

[0040] C 7 -C 18 -aralkyl radical represents, for example, benzyl, o-, m-, p-tolyl, 2,3-, 2,4-, 2,5-, 2,6-, 3,4-, 3,5-xylyl or mesityl.

[0041] Suitable substituents are alkyl, cycloalkyl, aryl, aralkyl, alkoxy, halogen, ether, thioether, disulfide, sulfoxide, sulfone, sulfonate, amino, aldehyde, keto, carboxylic ester, carboxylic acid, carbonate, carboxylate, cyano, alkylsilane, and alkoxysilane groups, as well as carboxamide groups.

[0042] A in formula I is preferably an ethylene bridge.

[0043] In a particularly preferred embodiment, the monomer according to formula I is 3,4-ethylenedioxythiophene.

[0044] Monomers according to formula II The conductive polymer according to the invention is an oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula II, [ka] Formula II During the ceremony, Ra and Rb are independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group.

[0045] Ra and Rb in formula II preferably represent alkyl groups.

[0046] In a particularly preferred embodiment, the monomer according to formula II is 3,4-dimethoxythiophene.

[0047] Exemplary monomers according to Formula II are shown in Table 1, but are not limited to these. [Table 1-1] [Table 1-2] [Table 1-3]

[0048] Polyanions The conductive polymer dispersion comprises a polymeric polyanion, wherein at least 75 mol %, more preferably at least 80 mol %, more preferably at least 90 mol %, and most preferably at least 99 mol % of the monomer units of the polyanion have a substituent selected from the group consisting of sulfonic acid or a salt thereof, phosphonic acid or a salt thereof, phosphoric acid ester or a salt thereof, sulfuric acid ester or a salt thereof, and carboxylic acid or a salt thereof.

[0049] The functional group is preferably a sulfonic acid or a salt thereof.

[0050] The polymeric polyanions can be copolymers of different monomers, but are preferably homopolymers.

[0051] In a particularly preferred embodiment, the polymeric polyanion is styrene-based.

[0052] According to a particularly preferred embodiment, the polyanion is poly(4-styrenesulfonic acid) or a salt thereof.

[0053] The weight average molecular weight (Mw) of the polymeric anion is not particularly limited, but is preferably 1,000 to 1,000,000 Da, more preferably 50,000 to 500,000 Da, and most preferably 100,000 to 300,000 Da.

[0054] Preparation of conductive polymers The polythiophene polymers are preferably prepared by oxidative polymerization of the above-described thiophene monomers in an aqueous medium.

[0055] The oxidative polymerization is preferably carried out in the presence of a polyanion.

[0056] The concentration of the thiophene monomer in the aqueous phase medium is preferably in the range of 0.1 to 25% by weight, preferably in the range of 0.5 to 10% by weight, all based on the total weight of the aqueous reaction medium.

[0057] Suitable oxidizing agents include iron(III) salts, such as FeCl 3 , and iron(III) salts of aromatic and aliphatic sulfonic acids;H 2 O 2 ;K 2 Cr 2 O 7 ;KMnO 4 , alkali metal perborates; alkali metal or ammonium persulfates; and mixtures thereof.

[0058] Further suitable oxidizing agents are described, for example, in Handbook of Conducting Polymers (Ed. Skotheim, TA), Marcel Dekker: New York, 1986, Vol. 1, pages 46-57.

[0059] Particularly preferred oxidizing agents are peroxodisulfates, especially K 2 S 2 O 8 , Na 2 S 2 O 8 iron(III) salts, especially iron(III) chloride; or combinations thereof.

[0060] Particularly suitable are mixtures of peroxodisulfate with at least one further compound which catalyzes the cleavage of peroxodisulfate, such as an Fe(III) salt.

[0061] According to a particularly preferred embodiment, the oxidizing agent is Fe 2 (SO 4 ) 3 and Na 2 S 2 O 8 It is a mixture of.

[0062] The aqueous reaction medium can be prepared in various ways: the thiophene monomer can be dissolved or dispersed in the aqueous reaction medium, followed by the addition of the oxidizing agent(s), which can also be dissolved or dispersed in the aqueous phase, or the oxidizing agent(s) can be first dissolved or dispersed in the aqueous reaction medium, followed by the addition of the thiophene monomer, which can also be dissolved or dispersed in the aqueous phase.

[0063] More than one oxidizing agent, e.g. Fe 2 (SO 4 ) 3 and Na 2 S 2 O 8 When a mixture of these components is used, it is further possible to first mix one of these components with the thiophene monomer in the aqueous reaction medium and subsequently add the second oxidizing agent.

[0064] The oxidative polymerization is preferably carried out under an inert atmosphere, as disclosed in EP-11453877 (Agfa Gevaert). The oxygen content of the reaction medium is preferably less than 3 mg / liter, more preferably less than 1.5 mg / liter, most preferably less than 0.5 mg / liter, when an oxidizing agent, for example peroxodisulfate, is added thereto.

[0065] The oxygen concentration in the reaction medium can be controlled by any means, such as freeze-thaw techniques, bubbling an inert gas (such as argon, nitrogen, or helium) through the reaction medium for extended periods of time, consuming oxygen by a sacrificial reaction under an inert gas atmosphere, etc. The inert gas is preferably bubbling through the reaction medium until polymerization is complete, thereby maintaining the oxygen concentration below 3 mg / l.

[0066] The oxidative polymerization is preferably carried out at low pH, as disclosed in EP-A 1384739 (Heraeus). The pH is preferably below 1.5, more preferably below 1.00.

[0067] For pH adjustment, an acid can be used, and the acid is preferably selected from the group of water-soluble inorganic acids and water-soluble organic acids. Examples of inorganic acids include hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid. Examples of organic acids include p-toluenesulfonic acid, benzenesulfonic acid, methanesulfonic acid, and trifluoromethanesulfonic acid.

[0068] The temperature of the reaction mixture is preferably 0 to 100°C, more preferably 0 to 50°C, and most preferably 5 to 30°C.

[0069] The amounts of thiophene monomer and polyanion in the reaction mixture are selected such that a stable polythiophene / polyanion dispersion is obtained, the solids content in the dispersion being preferably 0.05-25 wt. %, more preferably 0.1-10 wt. %, and most preferably 0.8-2 wt. %.

[0070] After the polymerization reaction is complete, the liquid composition can be further purified, for example by filtration, in particular ultrafiltration, and / or treatment with ion exchangers, in particular anion and cation exchangers.

[0071] After the purification process, the conductive polymer dispersion can be further optimized for its intended use. For example, when used to prepare an antistatic layer, the liquid formulations described below can be prepared from the conductive polymer dispersion.

[0072] During the preparation of the conductive polymer, various homogenization techniques can be used. The homogenization techniques can be selected from: -Ultrasonic homogenization technique; -Pressure homogenization technique; and -Mechanical homogenization techniques.

[0073] Suitable mechanical homogenizers are rotor-stator homogenizers and blade homogenizers. Another mechanical homogenization technique is the use of a spinning disc reactor.

[0074] Suitable high pressure homogenizers, such as a Gaulin homogenizer or an Ariete homogenizer, force the dispersion through very narrow channels or orifices under pressure. Another suitable high pressure homogenizer is a microfluidizer.

[0075] Two or more homogenizers can be used in combination, preferably in sequential mode.

[0076] Homogenization techniques can be used before, during, and after the polymerization reaction. Such homogenization techniques can also be used during the preparation of the liquid formulations described below.

[0077] liquid formulation Depending on the application for which the conductive polymer dispersion is to be used, additional components can be added to the conductive polymer dispersion to form a liquid formulation optimized for the application.

[0078] All or part of the additional components described below may also be added to the conductive polymer dispersion described above.

[0079] In addition to the conductive polymer and polyanion described above, the formulations may contain further additives, such as, for example, solvents, surfactants, adhesion promoters, crosslinking agents, binders, conductivity enhancing compounds, heat and moisture stability improving compounds, acidic compounds, and pH adjusting compounds.

[0080] A suitable solvent is water or a water-miscible solvent, or a mixture thereof. The water-miscible solvent is preferably selected from the group consisting of aliphatic alcohols, such as methanol, ethanol, n-propanol, and isopropanol; diacetone alcohol; aliphatic ketones, such as acetone; and methyl ethyl ketone.

[0081] According to a preferred embodiment of the liquid formulation, at least 95% by weight, more preferably at least 99% by weight, most preferably at least 99.5% by weight of the total amount of solvent in the liquid formulation is water or a mixture of water and alcohol, the alcohol being selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, or a combination thereof.

[0082] The liquid formulation preferably comprises 2-50% by weight of an organic solvent, which is preferably methanol, ethanol, n-propanol, isopropanol, n-butanol, or a combination thereof.

[0083] The surfactant compound can be: anionic surfactants, such as alkylbenzenesulfonic acids and salts, paraffin sulfonates, alcohol sulfonates, ether sulfonates, sulfosuccinates, phosphate esters, alkyl ether carboxylic acids, or carboxylates; cationic surfactants, such as quaternary alkyl ammonium salts; non-ionic surfactants, such as linear alcohol ethoxylates, oxo alcohol ethoxylates, alkylphenol ethoxylates or alkyl polyglucosides; and - zwitterionic surfactants, for example compounds having both a carboxylic acid group and a quaternary ammonium group (e.g., lauryl-N,N-(dimethyl-ammonio)butyrate and lauryl-N,N-(dimethyl)-glycine betaine, etc.), compounds having both a sulfate group and a quaternary ammonium group (e.g., 3-[(3-cholamido-propyl)dimethylammonio]-1-propanesulfonate, 3-(4-tert-butyl-1-pyridinio)-1-propanesulfonate, 3-( ... compounds with both a phosphate group and a quaternary ammonium group (such as those with hexadecylphosphocholine), compounds with a quaternary ammonium group with an appended hydroxy group (such as lauryldimethylamine N-oxide), and phospholipids consisting of a quaternary ammonium head coupled to two hydrophobic fatty acids via a phosphate group and glycerol.

[0084] Particularly suitable surfactants are those commercially available under the Dynol® and Zonyl® trademarks.

[0085] Suitable adhesion promoters are organofunctional silanes or their hydrolysates, such as 3-glycidoxypropyltrialkoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, or octyltriethoxysilane.

[0086] Suitable crosslinking agents are melamine compounds, blocked isocyanates, functional silanes such as tetraethoxysilane, alkoxysilane hydrolysates such as tetraethoxysilane, epoxy silanes such as 3-glycidoxypropyltrialkoxysilane, and the like.

[0087] Particularly preferred crosslinkers are tetraalkyl orthosilicates, which are selected from the group consisting of tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, tetrapentyl orthosilicate, orthosilicate esters and at least partial hydrolysis products of these orthosilicate esters, with tetraethyl orthosilicate (TEOS) being particularly preferred.

[0088] The amount of crosslinker is preferably from 0.01 to 15% by weight, more preferably from 0.1 to 10% by weight, and most preferably from 1 to 5% by weight, all based on the total weight of the liquid formulation.

[0089] Suitable binders are selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl chloride, polyvinyl acetate, polyvinyl butyrate, polyacrylic esters, polyacrylamides, polymethacrylic esters, polymethacrylamides, polyacrylonitrile, styrene / acrylic esters, vinyl acetate / acrylic esters, ethylene / vinyl acetate copolymers, polybutadiene, polyisoprene, polystyrene, polyethers, polyesters, sulfonated polyesters, polycarbonates, polyurethanes, polyamides, polyimides, polysulfones, melamine-formaldehyde resins, epoxy resins, silicone resins, silane resins, cellulose, or a mixture of at least two of these binders.

[0090] Other suitable binders are those obtained by adding a crosslinking agent to a crosslinkable polymer, followed by crosslinking, such as a melamine compound, a capped isocyanate, or a functional silane (such as 3-glycidoxypropyltrialkoxysilane, tetraethyl orthosilicate, and tetraethyl orthosilicate hydrolyzate), and the crosslinkable polymer is such as a polyurethane, a polyacrylate, or a polyolefin.

[0091] Highly suitable binders are water-soluble binders, for example sulfonated polyesters.

[0092] The liquid formulation preferably comprises a high boiling point solvent, such as propylene glycol, ethylene glycol, diethylene glycol, dimethylsulfoxide (DMSO), methylacetamide, dimethylacetamide, dimethylformamide, N-methylpyrrolidone, N-cyclohexylpyrrolidone, or a mixture of at least two of these solvents.

[0093] Addition of such high boiling point solvents to the liquid formulation in an amount of 0.1 to 10 wt %, preferably 0.5 to 5 wt %, based on the total weight of the liquid formulation, can result in a significant improvement in electrical conductivity.

[0094] Highly suitable high boiling point solvents are selected from the group consisting of N-hydroxyethyl-pyrrolidone, DMSO, ethylene glycol, and diethylene glycol.

[0095] A preferred stability improving compound is gallic acid or a derivative thereof, a preferred derivative being a gallic acid ester.

[0096] Particularly suitable gallic acid esters are esters of gallic acid and sugars, which are often called tannins or gallotannins. Further suitable gallic acid esters are alkyl, alkenyl, cycloalkyl, cycloalkenyl and aryl esters of gallic acid, preferably those having 1 to 15, preferably 1 to 6, C atoms in the alkyl, alkenyl, cycloalkyl, cycloalkenyl or aryl group of the ester.

[0097] Suitable gallic acid derivatives are gallotannins, such as tannic acid, or gallic acid alkyl esters, such as methyl gallate, ethyl gallate, propyl gallate, or a mixture of at least two of these esters.

[0098] The amount of the stability improving compound is preferably from 0.01 to 10% by weight, more preferably from 0.1 to 5% by weight, and most preferably from 0.5 to 2.5% by weight, in each case based on the total weight of the liquid formulation.

[0099] The pH of the liquid formulation is typically between 1.5 and 8.0.

[0100] The pH can be adjusted by adding a suitable acid or base to the liquid formulation. Suitable acids include inorganic or organic acids. Examples of inorganic acids are sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, silicic acid, or combinations thereof. Examples of organic acids are acetic acid, formic acid, benzoic acid, p-toluenesulfonic acid, PSS, or combinations thereof. Suitable bases include inorganic or organic bases. Examples of inorganic bases are sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, or combinations thereof. Examples of organic bases are dimethylaminoethanol, imidazole, ammonia, alkylamines, or combinations thereof.

[0101] The viscosity of the liquid formulation was measured using a rheometer at 20 °C and a shear rate of 100 s -1 The viscosity is preferably 5 to 1000 mPa·s, more preferably 15 to 500 mPa·s, and most preferably 20 to 100 mPa·s, as measured by a viscosity measuring instrument.

[0102] Viscosity adjustment can be accomplished, for example, by adding an appropriate rheology modifier to the liquid formulation.

[0103] Furthermore, V t0 Let be the viscosity of the liquid formulation at time t = 0, and V t0+6month is the viscosity of the liquid formulation after storage of the same liquid formulation in a closed container at 25° C. for 6 months, it is preferred that the change in viscosity is no more than 20%, preferably no more than 10%, and more preferably no more than 5%, in which case the change in viscosity (ΔV) is calculated as follows: ΔV = 100% × (V t0+6month -V t0 ) / V t0

[0104] Even more preferably, the conductive layer prepared from the liquid formulation is characterized by at least one of the following properties, and preferably all of these properties: -Sheet resistance is 1×10 2 ~1×10 10 Ω / sq range, preferably 1×10 3 ~1×10 9 in the range of Ω / sq; a transmission of at least 98%, preferably at least 98.5%, more preferably at least 99%, most preferably at least 99.5%; a pencil hardness of at least 6H, preferably at least 7H, more preferably at least 8H and most preferably at least 9H.

[0105] Particularly preferred in this context are SR t0 , T t0 , and PH t0 are the sheet resistance, transmittance, and pencil hardness at time t=0 of a conductive layer prepared by coating a liquid formulation on a substrate at a wet film thickness of 12 mm and subsequent removal of the solvent, and SR t0+6month , T t0+6month , and PH t0+6month When the same liquid formulation is coated on a substrate at a wet film thickness of 12 mm, followed by removal of the solvent to prepare a conductive layer, the sheet resistance, transmittance, and pencil hardness after storage at 25° C. in a closed container for 6 months satisfy at least one of the following properties, and preferably all of these properties: the sheet resistance change is less than or equal to 20%, preferably less than or equal to 10%, most preferably less than or equal to 5%, the sheet resistance change (ΔSR) being calculated as follows: ΔSR = 100% × (SR t0+6month -SR t0 ) / SR t0 the change in transmittance is less than or equal to 20%, preferably less than or equal to 10%, most preferably less than or equal to 5%, the change in transmittance (ΔT) being calculated as follows: ΔT = 100% × (Tt0+6month -T t0 ) / T t0 the pencil hardness change is less than or equal to 20%, preferably less than or equal to 10%, most preferably less than or equal to 5%, the pencil hardness change (ΔPH) being calculated as follows: ΔPH = 100% × (PH t0+6month -PH t0 ) / PH t0

[0106] The solids content of the liquid formulation is preferably from 0.01 to 20% by weight, more preferably from 0.1 to 15% by weight, most preferably from 0.25 to 10% by weight, in each case based on the total weight of the formulation.

[0107] Laminate The laminate according to the present invention has a conductive layer provided on a substrate, the conductive layer comprising: (a) at least one oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula I with at least one monomer according to formula II; [ka] Formula I [ka] Formula II During the ceremony, A is a substituted or unsubstituted C 1 -C 5 represents an alkylene bridge; R is a linear or branched, substituted or unsubstituted C 1 -C 18 -Alkyl group, substituted or unsubstituted C 5 -C 12 -Cycloalkyl group, substituted or unsubstituted C 6 -C 14 -aryl group, substituted or unsubstituted C 7 -C 18 -Aralkyl group, substituted or unsubstituted C 1 -C 4 - selected from the group consisting of hydroxyalkyl groups, and hydroxyl groups; s represents an integer from 0 to 8; Ra and Rb are independently selected from the group consisting of hydrogen, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkenyl groups, substituted or unsubstituted alkynyl groups, substituted or unsubstituted aralkyl groups, substituted or unsubstituted alkaryl groups, and substituted or unsubstituted aryl or heteroaryl groups; and (b) at least one polymeric polyanion, at least 75 mol % of the monomer units of which are functionalized, the functional groups being selected from the group consisting of sulfonic acid or its salt, phosphonic acid or its salt, phosphoric acid ester or its salt, sulfuric acid ester or its salt, and carboxylic acid or its salt; Including, It is characterized in that the weight ratio of the monomer according to formula I to the monomer according to formula II is from 75 / 25 to 25 / 75, preferably from 70 / 30 to 40 / 60, more preferably from 65 / 35 to 50 / 50.

[0108] Suitable substrates are plastics, such as polycarbonate, polyethylene, polyethylene terephthalate (PET), polyamide, and polypropylene.

[0109] Surface activation, such as corona treatment, can be performed prior to application of the liquid formulation to enhance adhesion to the substrate, for example in the case of PET and polyolefins.

[0110] The substrate may also be a glass plate.

[0111] The conductive layer is preferably characterized by at least one of the following properties, more preferably all of these properties: -Sheet resistance is 1×10 2 ~1×10 10 Ω / sq range, preferably 1×10 3 ~1×10 9 in the range of Ω / sq; - a transmittance of at least 98%, preferably at least 98.5%, more preferably at least 99%, most preferably at least 99.5%; a pencil hardness of at least 6H, preferably at least 7H, more preferably at least 8H and most preferably at least 9H.

[0112] The laminates according to the invention are suitable for use as electronic components, in particular as conductive or antistatic means, as transparent heat transfer parts or as electrodes.

[0113] The laminate can be used as electronic components (e.g., on films), packaging of electronic components, for finishing films of plastics, and for coating screens.The laminate can also be used as a substrate for transparent electrodes (e.g., in displays), such as indium-tin oxide electrodes, or as a conductor in polymer electronics.Further possible applications include sensors, batteries, solar cells, electrochromic windows (smart windows), and displays, as well as corrosion protection.

[0114] Considering the UV stability and scratch resistance of the coatings obtained with the liquid formulations according to the invention, these liquid formulations are particularly useful for the manufacture of antistatic coatings or electromagnetic wave shields. These liquid formulations are further particularly useful for the preparation of hole transport layers in organic light emitting diode (OLED) or organic photovoltaic (OPV) devices. Preparation of the Laminate

[0115] The method for preparing the laminate comprises the following steps: i) providing a substrate; ii) applying a liquid formulation according to the present invention; iii) at least partially removing the solvent from the liquid composition to obtain a laminate having a conductive layer coating the substrate; Includes.

[0116] In step i), a substrate is first provided, the nature of which depends on the intended purpose for which the composition according to the invention is employed. In step ii), the liquid composition according to the invention is applied onto the substrate. The application of the liquid formulation can be carried out by known methods, for example by spin coating, dipping, pouring, dripping on, spraying, atomizing, knife coating, brushing, or printing (such as inkjet printing, screen printing, gravure printing, offset printing, or tampon printing).

[0117] In step iii), the solvent is at least partially removed to obtain a laminate having a conductive layer coating the substrate, preferably by drying the substrate coated with the composition at a temperature in the range of 20° C. to 200° C. EXAMPLES

[0118] material All materials used in the following examples were readily available from standard sources, e.g., ALDRICH CHEMICAL Co. (Belgium) and ACROS (Belgium), unless otherwise stated. Water used was deionized water.

[0119] EDOT is 3,4-ethylenedioxythiophene, sold by Heraeus.

[0120] DMOT is 3,4-dimethoxythiophene, sold by Fluorochem Ltd.

[0121] PSS is an aqueous solution of polystyrene sulfonic acid having a molecular weight of 300 kDa, and was prepared according to the method disclosed in Houben-Weyl, Methoden der organischen Chemie, Vol. E 20, Makromolekulaire Stoffe, Teil 2 (1987), page 1141).

[0122] Lewatit® MonoPlus M600 is a basic gelular anion exchange resin, sold by Lanxess AG.

[0123] Lewatit® MonoPlus S 108 H is an acidic gel-like anion exchange resin, sold by Lanxess AG.

[0124] method Surface resistance measurement The surface resistance SER was measured at room temperature using a two-terminal method.

[0125] Viscosity measurement The viscosity was measured with a glass capillary viscometer.

[0126] Measurement of gelation stability Gel stability was evaluated by mixing equal amounts of organic solvent and conductive polymer dispersion and visually evaluating the gelation behavior over time. Samples were stored at room temperature or at 30° C. A quantitative scale of gelation behavior was determined from (1-5), where 1 corresponds to no observed viscosity increase and 5 corresponds to complete gelation.

[0127] Example 1: P(EDOT 0.90 :DMOT 0.10 ): Synthesis of PSS An aqueous solution of PSS (297 g, 5.74 wt%) was mixed with deionized water (1288 mL) in a reaction vessel under a nitrogen flow. EDOT (6.17 g, 43.4 mmol) and DMOT (0.69 g, 4.8 mmol) were added. The reaction mixture was heated to 30° C. with stirring. A solution of iron(III) sulfate (0.31 g, 0.77 mmol) in deionized water (6.4 mL) was then added. Sodium persulfate (13.7 g, 57.8 mmol) was added and the reaction mixture was stirred for 6 hours. An additional amount of sodium persulfate (2.3 g, 9.6 mmol) was added to the reaction mixture and stirred for an additional 16 hours. The reaction mixture was treated with an ion exchanger (223.9 g Lewatit® MonoPlus M600+419.4 g Lewatit® MonoPlus S 108 H, filtered and washed twice with 120 mL water, this was repeated).

[0128] The resulting viscous mixture was divided into two and subjected to high shear homogenization to obtain two samples (Lab Gaulin, a: 1×600 bar and b: 4×600 bar). The dispersion was concentrated in vacuum.

[0129] This procedure yielded a blue PEDOT:PSS aqueous dispersion (a: 1.12 wt % and b: 1.24 wt %).

[0130] Example 2: P(EDOT 0.80 :DMOT 0.20 ): Synthesis of PSS The polymerization was carried out in a similar manner to Example 1, except that 5.49 g of EDOT and 1.37 g of DMOT were used. The reaction mixture was treated with an ion exchanger (223.5 g of Lewatit® MonoPlus M600 + 418.8 g of Lewatit® MonoPlus S 108 H, filtered and washed twice with 120 mL of water, this was repeated).

[0131] This procedure yielded a blue PEDOT:PSS aqueous dispersion (a: 1.12 wt % and b: 1.24 wt %).

[0132] Example 3: P(EDOT0.65 :DMOT 0.35 ): Synthesis of PSS The polymerization was carried out in a similar manner as in Example 1, except that 298.66 g of poly(4-vinylbenzenesulfonic acid), 4.46 g of EDOT, and 2.4 g of DMOT were used. The reaction mixture was treated with an ion exchanger (223.1 g of Lewatit® MonoPlus M600 + 417.9 g of Lewatit® MonoPlus S 108 H, filtered and washed twice with 120 mL of water, this was repeated).

[0133] This procedure yielded a blue PEDOT:PSS aqueous dispersion (a: 1.23 wt % and b: 1.12 wt %).

[0134] Example 4: P(EDOT 0.50 :DMOT 0.50 ): Synthesis of PSS The polymerization was carried out in a similar manner to Example 3, except that 3.43 g of EDOT and 3.43 g of DMOT were used. The reaction mixture was treated with an ion exchanger (222.6 g of Lewatit® MonoPlus M600 + 417.0 g of Lewatit® MonoPlus S 108 H, filtered and washed twice with 120 mL of water, this was repeated).

[0135] This procedure yielded a blue PEDOT:PSS aqueous dispersion (a: 1.21 wt % and b: 1.33 wt %).

[0136] Comparative Example 1: Polymerization of PEDOT:PSS In a reaction vessel, an aqueous solution of PSS (73.2 g, 5.85 wt%) was mixed with deionized water (323 mL) under a nitrogen flow. EDOT (1.71 g, 12.1 mmol) was added. The reaction mixture was heated to 30° C. with stirring. Then, a solution of iron(III) sulfate (0.077 g, 0.19 mmol) in deionized water (1.6 mL) was added. Sodium persulfate (3.45 g, 14.5 mmol) was added and the reaction mixture was stirred for 6 hours. An additional amount of sodium persulfate (0.57 g, 2.42 mmol) was added to the reaction mixture and stirred for another 16 hours. The reaction mixture was treated with an ion exchanger (56.1 g Lewatit® MonoPlus M600 + 105.1 g Lewatit® MonoPlus S 108 H, filtered, repeated).

[0137] The resulting viscous mixture was subjected to high shear homogenization (Lab Gaulin, 1×600 bar) and the dispersion was concentrated in vacuum.

[0138] This procedure yielded a blue PEDOT:PSS aqueous dispersion (1.14 wt %).

[0139] Comparative Example 2: Polymerization of PEDOT:PSS In a reaction vessel, an aqueous solution of PSS (347 g, 5.86 wt%) was mixed with deionized water (1525 mL) under nitrogen bubbling. EDOT (8.14 g, 57.3 mmol) was added. The reaction mixture was heated to 30° C. with stirring. A solution of iron(III) sulfate (0.37 g, 0.93 mmol) in deionized water (20 mL) was then added. Sodium persulfate (16.4 g, 68.8 mmol) was added and the reaction mixture was stirred for 6 h. An additional amount of sodium persulfate (2.7 g, 11.3 mmol) was added to the reaction mixture and stirred for an additional 16 h. 1 L of the reaction mixture was treated with an ion exchanger (150 g Lewatit® MonoPlus M600 + 280 g Lewatit® MonoPlus S 108 H, filtered, repeated).

[0140] The resulting viscous mixture was subjected to high shear homogenization (Lab Gaulin, 4 x 600 bar) The dispersion was concentrated in vacuum.

[0141] This procedure yielded a blue PEDOT:PSS aqueous dispersion (1.22 wt %).

[0142] Example 5 The viscosities of the dispersions and the SER of films bar-coated with these dispersions on PET were measured as described above and are shown in Table 2. [Table 2]

[0143] As is evident from the results in Table 2, the SER of films prepared with dispersions containing increasing amounts of DMOT is similar.

[0144] The viscosity of the dispersion decreases with increasing amounts of DMOT and with stronger homogenization.

[0145] Example 6 The gelation stability of the dispersions when isopropanol was added was evaluated over time. The results of storage at room temperature are shown in Table 3, and the results of storage at 30° C. are shown in Table 4. [Table 3] [Table 4]

[0146] As is evident from the results in Tables 3 and 4, dispersions containing copolymers with increasing amounts of DMOT exhibit improved gelation stability to the addition of isopropanol.

[0147] Example 7 The gelation stability of the dispersion when ethanol was added was evaluated over time. The results when stored at room temperature are shown in Table 5, and the results when stored at 30° C. are shown in Table 6. [Table 5] [Table 6]

[0148] As is evident from the results in Tables 5 and 6, dispersions containing copolymers with increasing amounts of DMOT show improved gelation stability to the addition of ethanol.

Claims

1. 1. A conductive polymer dispersion comprising: (a) at least one oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula I with at least one monomer according to formula II, 【Chemistry 1】 Formula I 【Chemistry 2】 Formula II During the ceremony, A is a substituted or unsubstituted C １ -C ５ represents an alkylene bridge; R is a linear or branched, substituted or unsubstituted C １ -C １８ -Alkyl group, substituted or unsubstituted C ５ -C １２ -Cycloalkyl group, substituted or unsubstituted C ６ -C １４ -aryl group, substituted or unsubstituted C ７ -C １８ - selected from the group consisting of aralkyl groups, and hydroxyl groups; s represents an integer from 0 to 8; Ra and Rb are each independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group; and (b) a polymeric polyanion, wherein at least 75 mol % of the monomer units of the polymeric polyanion have a functional group selected from the group consisting of sulfonic acid or a salt thereof, phosphonic acid or a salt thereof, phosphoric acid ester or a salt thereof, sulfuric acid ester or a salt thereof, and carboxylic acid or a salt thereof; (c) a dispersion medium selected from water, a water-soluble organic solvent, or a mixture thereof; Including, characterized in that the weight ratio of the monomer according to formula I to the monomer according to formula II is 25 / 75 to 75 / 25; The conductive polymer dispersion.

2. 2. The conductive polymer dispersion of claim 1, wherein the weight ratio of the monomer according to formula I to the monomer according to formula II is from 50 / 50 to 65 / 35.

3. The conductive polymer dispersion according to claim 1 or 2, wherein said monomer according to formula I is 3,4-ethylenedioxythiophene.

4. 20. The conductive polymer dispersion according to any one of the preceding claims, wherein said monomer according to formula II is 3,4-dimethoxythiophene.

5. 10. A conductive polymer dispersion according to any one of the preceding claims, wherein the polymeric polyanion is poly(4-styrenesulfonic acid) or a salt thereof.

6. 2. A conductive polymer dispersion according to any one of the preceding claims, wherein the polymeric polyanion has a weight average molecular weight (Mw) of 50 000 to 500 000 Da.

7. The oligothiophene or polythiophene and the polyanion have a median particle size (d ５０ 20. The conductive polymer dispersion according to claim 1, wherein the conductive polymer is present as polythiophene / polyanion particles having a molecular weight of 5 to 100 nm.

8. The amount of the oligothiophene or polythiophene / polyanion particles is 1.1 to 1.3 wt % based on the total weight of the dispersion, and the viscosity of the dispersion is 1.0 to 1.5 wt % at a shear rate of 100 s at 20° C. －１ The conductive polymer dispersion according to claim 7, having a viscosity of 5 to 100 mPa·s as measured by a .

9. A liquid formulation comprising a conductive polymer dispersion according to any one of the preceding claims.

10. 10. The liquid formulation of claim 9, comprising 2-50% by weight of at least one organic solvent, based on the total weight of the formulation.

11. 11. The liquid formulation of claim 10, wherein the organic solvent is selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, or combinations thereof.

12. The liquid formulation of any one of claims 9 to 11, further comprising an acid, a base, a high boiling point solvent, an adhesion promoter, a crosslinking agent, a surfactant, a coupling agent, or a combination thereof.

13. Use of a liquid formulation according to any one of claims 9 to 12 for the preparation of an antistatic coating or an electromagnetic wave shield or for the preparation of a hole transport layer in an organic light emitting diode (OLED) or organic photovoltaic (OPV) device.

14. 1. A method for preparing a laminate comprising the steps of: (i) providing a substrate; (ii) applying onto said substrate a liquid formulation according to any one of claims 9 to 12; (iii) at least partially removing the solvent from the liquid formulation to obtain a laminate having a conductive layer on a liquid formulation substrate; The method comprising:

15. A laminate having a conductive layer provided on a substrate, the conductive layer comprising: (a) at least one oligothiophene or polythiophene obtained by copolymerization of at least one monomer according to formula I with at least one monomer according to formula II; 【Chemistry 3】 Formula I 【Chemistry 4】 Formula II During the ceremony, A is a substituted or unsubstituted C １ -C ５ represents an alkylene bridge; R is a linear or branched, substituted or unsubstituted C １ -C １８ -Alkyl group, substituted or unsubstituted C ５ -C １２ -Cycloalkyl group, substituted or unsubstituted C ６ -C １４ -aryl group, substituted or unsubstituted C ７ -C １８ - selected from the group consisting of aralkyl groups, and hydroxyl groups; s represents an integer from 0 to 8; Ra and Rb are each independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group; ,and, (b) a polymeric polyanion, at least 75 mol % of the monomer units of the polymeric polyanion having a functional group selected from the group consisting of sulfonic acid or a salt thereof, phosphonic acid or a salt thereof, phosphoric acid ester or a salt thereof, sulfuric acid ester or a salt thereof, and carboxylic acid or a salt thereof; Including, The laminate, characterized in that the weight ratio of the monomer according to formula I to the monomer according to formula II is from 25 / 75 to 75 / 25.

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