Method for producing conductive composites, and composition

Abstract

A method for producing a conductive composite is provided, comprising: a polythiophene generation step of polymerizing a cationic thiophene in a polyanion to produce a cationic polythiophene that forms a conductive composite with the polyanion; a termination step of stopping the polymerization reaction in the polythiophene generation step; and a purification step of purifying the conductive composite with a first ion exchange resin after the termination step. A composition is provided comprising a polyanion containing sulfonic acid groups with a weight-average molecular weight of 50,000 to 1,000,000 and a cationic polythiophene that forms a conductive composite with the polyanion, wherein the SO4 ion concentration relative to the conductive composite is 1,400 PPM or less.

Description

Technical Field

[0001] The present invention relates to a method for producing a conductive composite and a composition.

Background Art

[0002] Patent Document 1 discloses "A method for purifying a conductive polymer, characterized by fractionating a conductive polymer composed of a donor polymer and an acceptor polymer by bringing the conductive polymer into contact with an ion exchange resin in a solvent or dispersion medium, and performing ion exchange on the low-molecular-weight side thereof. (Claim 1)". Patent Document 2 discloses "A conductive polymer comprising a polymer compound, wherein the iron ion content is in the range of 0.1 to 10 ppm by mass%. (Claim 1)". Patent Document 3 discloses "A conductive polymer-containing liquid comprising a conductive composite containing a π-conjugated conductive polymer and a polyanion, and a dispersion medium, wherein the dispersion medium contains water and isopropanol, and the content of iron ions relative to the total mass of the conductive polymer-containing liquid is 0.200 ppm or less. (Claim 1)". Patent Document 4 discloses "A method for treating a nonionic surfactant containing metal ions, characterized by subjecting an aqueous diluted solution obtained by adding water to a nonionic surfactant containing metal ions such that the water content is 40.0 mass% or more and less than 98.0 mass% to an ion exchange method using a mixed resin of a strongly acidic cation exchange resin and a strongly alkaline anion exchange resin, and treating the nonionic surfactant such that the concentration of each metal ion relative to the nonionic surfactant is 5 ppb or less for each metal ion. (Claim 1)". Patent Document 5 discloses "A conductive polymer powder containing a π-conjugated conductive polymer and a polyanion, wherein the content ratio of the π-conjugated conductive polymer to the polyanion in the conductive polymer powder is (1:0.5) to (1:1) on a mass basis, and the iron content relative to the total mass of the conductive polymer powder is 0.65 mass% or less. (Claim 1)". [Prior Art Documents] [Patent Documents] [Patent Document 1] Japanese Unexamined Patent Publication No. 2006-005144 [Patent Document 2] Japanese Unexamined Patent Publication No. 2009-221417 [Patent Document 3] Japanese Unexamined Patent Publication No. 2023-032021 [Patent Document 4] Patent No. 5959134 [Patent Document 5] Japanese Unexamined Patent Publication No. 2022-052251 [Overview of the project] [Means for solving the problem]

[0003] In a first embodiment of the present invention, a method for producing a conductive composite is provided, comprising a polythiophene production step, a termination step, and a purification step. In the polythiophene production step, a cationic thiophene may be polymerized in a polyanion to produce a cationic polythiophene that forms a conductive composite with the polyanion. In the termination step, the polymerization reaction in the polythiophene production step may be terminated. The purification step is performed after the termination step. In the purification step, the composite may be purified with a first ion exchange resin.

[0004] In the above, the first ion exchange resin may include a cation exchange resin.

[0005] In the above, during the purification step, cation exchange resin may be used in an amount of 100 to 2000 parts by weight per 100 parts by weight of the solid content of the composite.

[0006] In the above, the first ion exchange resin may further contain an anion exchange resin.

[0007] In the above, during the purification stage, an anion exchange resin may be used in an amount of 100 to 2000 parts by weight per 100 parts by weight of the solid content of the composite.

[0008] In the above, a high-pressure emulsification step may be further provided after the stopping step and before the purification step, in which the complex is emulsified under high pressure.

[0009] In the above, the termination step may be performed by removing ions in the polymerization reaction using a second ion exchange resin.

[0010] In the above, the amount of the first ion exchange resin used in the purification stage may be 10 to 200 parts by weight relative to 100 parts by weight of the second ion exchange resin used in the termination stage.

[0011] In the above, the polyanion may be polystyrene sulfonic acid (PSS).

[0012] In the above, the cationic polythiophene may be polyethylenedioxythiophene (PEDOT).

[0013] In the above, the polyanion may be a monopolymer.

[0014] A second embodiment of the present invention provides a composition comprising a polyanion containing a sulfonic acid group having a weight-average molecular weight of 50,000 to 1,000,000, and a cationic polythiophene that forms a complex with the polyanion. In the composition, the SO4 ion concentration relative to the complex may be 1,400 PPM or less.

[0015] In the above, the Fe ion concentration in the complex may be 100 PPM or less.

[0016] In the above, the polyanion may be polystyrene sulfonic acid (PSS).

[0017] In the above, the cationic polythiophene may be polyethylenedioxythiophene (PEDOT).

[0018] In the above, the polyanion may be a monopolymer.

[0019] In the above, the composition is a powdered composition, and the particle size of the composition may be 0.3 μm or more and 30 μm or less.

[0020] It should be noted that the above summary of the invention does not enumerate all of the required features of the present invention. Furthermore, sub-combinations of these feature groups may also constitute inventions. [BRIEF DESCRIPTION OF THE DRAWINGS]

[0021] [Figure 1] 1 shows an example of an antistatic film 10 according to the present embodiment. [Figure 2] 11 shows an example of a flow of a method for producing a composition and an antistatic film according to the present embodiment. [MODE FOR CARRYING OUT THE INVENTION]

[0022] Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Not all combinations of features described in the embodiments are necessarily essential to the solution of the invention. Furthermore, embodiments will be described with reference to the drawings, and in the description of the drawings, the same or similar parts may be assigned the same reference numerals, and overlapping descriptions may be omitted.

[0023] [Antistatic Film] Fig. 1 shows an example of an antistatic film 10 according to the present embodiment. The antistatic film 10 is a film having an antistatic function, and is used for easily chargeable electrical devices such as displays and mobile phone terminals. The antistatic film 10 includes a transparent base material 110 and an antistatic layer 120 provided on the transparent base material. The antistatic film 10 may include other layers as necessary.

[0024] The transparent base material 110 may be a transparent plate-like or film-like base material such as glass or PET. The antistatic film 10 does not need to include the transparent base material 110, and may be formed only of the antistatic layer 120.

[0025] The antistatic layer 120 contains an antistatic composition (hereinafter also simply referred to as "the composition"). The composition functions as an antistatic agent by enhancing conductivity through the inclusion of a so-called conductive polymer. The thickness of the antistatic layer is preferably 0.001 to 10 μm, and more preferably 0.01 to 5 μm. The thickness of the antistatic layer may be measured using a step gauge (e.g., Bruker DektakXY) or an optical interferometer (e.g., CYBERNET F series). Details of the composition are described below.

[0026] [Composition] The composition comprises a polyanion containing a sulfonic acid group, and a cationic polythiophene that forms a conductive composite with the polyanion.

[0027] When the composition is coated onto a PET substrate with a film thickness of 0.1 μm, the surface resistivity may be 5,000 to 1,000,000 Ω / sq. This ensures sufficient conductivity, i.e., antistatic performance, when the composition is used as an antistatic agent.

[0028] [Polyanion] A polyanion containing a sulfonic acid group (hereinafter also simply referred to as "polyanion") may be an anionic polymer compound. An anionic polymer compound may be a polymer compound having an anionic group in its molecule that can undergo chemical oxidative doping to a cationic polythiophene. The anionic group includes at least a sulfonic acid group. The anionic group may further include one or more selected from a sulfate ester group, a phosphate ester group, a phosphate group, and a carboxyl group.

[0029] The polyanion may be a monopolymer. Alternatively, the polyanion may be a copolymer.

[0030] For example, the polyanion may be polystyrene sulfonic acid (PSS). The method for producing the polyanion will be described later. The polyanion may have terminal structures derived from the structure of the RAFT agent used in polymerization, as will be described later.

[0031] The polyanion may have a weight-average molecular weight (Mw) of, for example, 10,000 to 1,000,000, preferably 50,000 to 300,000. The molecular weight dispersion (PDI) of the polyanion may be between 1.0 and 2.5, but is not limited to this. Here, PDI is the ratio of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) (i.e., Mw / Mn).

[0032] [Polythiophene] The cationic polythiophene that forms a conductive composite with a polyanion may be a polythiophene that can become cationic by forming a conductive composite with a polyanion. The cationic polythiophene may be a polythiophene-based conductive polymer. The cationic polythiophene may be produced by polymerizing a cationic thiophene in a polyanion.

[0033] Cationic polythiophenes may be unsubstituted polythiophenes or polythiophenes substituted with one or more substituents. Substituents may include, for example, C1-C10 alkyl groups, C4-C20 aryl groups, halogen groups, alcohol groups, hydroxyl groups, alkoxy groups, carboxyl groups, carbonyl groups, ether groups, alkyldioxy groups, or alkoxycarbonyl groups.

[0034] For example, cationic polythiophenes include polythiophene, poly(3-methylthiophene), poly(3-ethylthiophene), poly(3-propylthiophene), poly(3-butylthiophene), poly(3-hexylthiophene), poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-decylthiophene), poly(3-dodecylthiophene), poly(3-octadecylthiophene), poly(3-bromothiophene), poly(3-chlorothiophene), and poly(3-iodothiophene). Poly(3-cyanothiophene), poly(3-phenylthiophene), poly(3,4-dimethylthiophene), poly(3,4-dibutylthiophene), poly(3-hydroxythiophene), poly(3-methoxythiophene), poly(3-ethoxythiophene), poly(3-butoxythiophene), poly(3-hexyloxythiophene), poly(3-heptyloxythiophene), poly(3-octyloxythiophene), poly(3-decyloxythiophene), poly(3-dodecyloxythiophene) Thiofen), poly(3-octadecyloxythiophene), poly(3,4-dihydroxythiophene), poly(3,4-dimethoxythiophene), poly(3,4-diethoxythiophene), poly(3,4-dipropoxythiophene), poly(3,4-dibutoxythiophene), poly(3,4-dihexyloxythiophene), poly(3,4-diheptyloxythiophene), poly(3,4-dioctyloxythiophene), poly(3,4-didecyloxythiophene), poly(3,4-didodecyl The following may be selected: oxythiophene, poly(3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene), poly(3,4-butylenedioxythiophene), poly(3-methyl-4-methoxythiophene), poly(3-methyl-4-ethoxythiophene), poly(3-carboxythiophene), poly(3-methyl-4-carboxythiophene), poly(3-methyl-4-carboxyethylthiophene), and poly(3-methyl-4-carboxybutylthiophene). The cationic polythiophene may be polyethylenedioxythiophene (PEDOT) in particular. This forms PEDOT-PSS when the polyanion is PSS.

[0035] The polymerization number and molecular weight dispersion (PDI) of the cationic polythiophene may be similar to those of the polyanion that forms the conductive composite.

[0036] The composition may contain no ionic components or only trace amounts of them. For example, the composition may contain anionic components such as SO4 ions, and / or cationic components such as Na ions and Fe ions (divalent or trivalent).

[0037] The composition may have an SO4 ion concentration of 1,400 PPM or less by weight, preferably 600 PPM or less, and more preferably 200 PPM or less. The composition may have an Fe ion (divalent or trivalent) concentration of 300 PPM or less by weight, preferably 200 PPM or less, more preferably 150 PPM or less, and most preferably 100 PPM or less. By setting the ion concentration (especially Fe ions) within the above range, the conductivity, dispersibility, and shelf life of the composition can be improved.

[0038] The composition may be solvent-free and consist substantially only of conductive composites, excluding the ionic components mentioned above. In this case, the composition may be in powder form. The particle size of the powder may be between 0.3 μm and 30 μm. The particle size may be determined by visually measuring the diameter of the smallest or largest particle in an image magnified at a predetermined magnification (e.g., 3000x) using the analysis mode of a HITACHI benchtop SEM (TM4000-PlusII). The powdered composition may contain a small amount of solvent (e.g., 20% or less by weight of water) in powder form.

[0039] Alternatively, the composition may further contain a solvent. The solvent may be water, such as deionized water or ultrapure water, or an organic solvent. For example, the organic solvent may be an alcohol-based solvent. The alcohol-based solvent may consist of one or more selected from isopropyl alcohol, methanol, and ethanol, or contain one or more of these. As an example, the alcohol-based solvent may contain water and an alcohol component which is one or more selected from isopropyl alcohol, methanol, and ethanol. The composition may be a solution in which polyanions and polythiophenes are at least partially dissolved in the solvent, or alternatively, a dispersion in which polyanions and polythiophenes are dispersed in the solvent.

[0040] The composition may contain an amount of solvent such that the concentrations of polyanions and polythiophenes are within a certain range. For example, the amount of polyanions and polythiophenes in the composition may be 10% by weight or less, or 5% by weight or less, and the lower limit should be such that the composition exhibits conductivity. The concentrations of polyanions and polythiophenes are preferably in the range of 0.005 to 2% by weight. By keeping the concentrations within this range, conductivity is sufficiently exhibited and viscosity stability is excellent.

[0041] For example, a solution composition with an NV value of 1.2% by mass may have an SO4 ion concentration of 16 PPM or less, preferably 10 PPM or less, and more preferably 2 PPM or less, relative to the total amount of the composition by weight. For example, a solution composition with an NV value of 1.2% by mass may have an Fe ion (divalent or trivalent) concentration of 1.5 PPM or less, preferably 1.0 PPM or less, relative to the total amount of the composition by weight.

[0042] [Manufacturing method] Figure 2 shows an example of a flow chart for manufacturing the conductive composite and composition according to this embodiment. For example, by performing each of the processes S100 to S600, the conductive composite and composition are manufactured, and an antistatic film is further manufactured. Some of S100 to S600 may be omitted. In addition to S100 to S600, other processes may be performed as needed. The conductive composite and the like may be produced by methods other than those shown in Figure 2.

[0043] First, the polyanion generation step is performed in S100. The polyanion described above is generated in the polyanion generation step. In the anion generation step, a polyanion may be generated having a weight-average molecular weight (Mw) of, for example, 10,000 to 1,000,000, preferably 50,000 to 300,000, and a molecular weight dispersion (PDI) of, for example, 2.5 or less, preferably 2 or less, more preferably 1.7 or less, and particularly preferably 1.5 or less.

[0044] Polyanions may be produced by polymerizing an anionic group-containing polymerizable monomer. For example, an anionic group-containing polymerizable monomer may be radically polymerized in a solvent in the presence of an initiator and / or a catalyst to obtain a polyanion. Living radical polymerization may be used as an example of radical polymerization.

[0045] An anionic group-containing polymerizable monomer may be a monomer having a functional group polymerizable with an anionic group within its molecule. Examples of anionic group-containing polymerizable monomers include vinyl sulfonic acid and its salts, allyl sulfonic acid and its salts, methallyl sulfonic acid and its salts, styrene sulfonic acid and its salts, methallyloxybenzene sulfonic acid and its salts, allyloxybenzene sulfonic acid and its salts, α-methylstyrene sulfonic acid and its salts, acrylamide-t-butyl sulfonic acid and its salts, 2-acrylamide-2-methylpropane sulfonic acid and its salts, cyclobutene-3-sulfonic acid and its salts, and Soprene sulfonic acid and its salts, 1,3-butadiene-1-sulfonic acid and its salts, 1-methyl-1,3-butadiene-2-sulfonic acid and its salts, 1-methyl-1,3-butadiene-4-sulfonic acid and its salts, ethyl acrylate sulfonic acid (CH2CH-COO-(CH2)2-SO3H) and its salts, propyl acrylate sulfonic acid (CH2CH-COO-(CH2)3-SO3H) and its salts, t-butyl acrylate sulfonic acid (CH2CH-COO-C(CH3)2CH2-SO3H) 3H) and its salts, n-butylsulfonic acrylate (CH2CH-COO-(CH2)4-SO3H) and its salts, ethylsulfonic allylate (CH2CHCH2-COO-(CH2)2-SO3H) and its salts, t-butylsulfonic allylate (CH2CHCH2-COO-C(CH3)2CH2-SO3H) and its salts, ethylsulfonic 4-pentenoate (CH2CH(CH2)2-COO-(CH2)2-SO3H) and its salts, propylsulfonic 4-pentenoate (CH2CH( CH2)2-COO-(CH2)3-SO3H) and its salts, 4-pentenoic acid-n-butylsulfonic acid (CH2CH(CH2)2-COO-(CH2)4-SO3H) and its salts, 4-pentenoic acid-t-butylsulfonic acid (CH2CH(CH2)2-COO-C(CH3)2CH2-SO3H) and its salts, 4-pentenoic acid-phenylenesulfonic acid (CH2CH(CH2)2-COO-C6H4-SO3H) and its salts, 4-pentenoic acid-naphthalenesulfonic acid (CH2CH(CH2)2-COO-C 10H8-SO3H) and its salts, ethyl sulfonic acid methacrylate (CH2C(CH3)-COO-(CH2)2-SO3H) and its salts, propyl sulfonic acid methacrylate (CH2C(CH3)-COO-(CH2)3-SO3H) and its salts, t-butyl sulfonic acid methacrylate (CH2C(CH3)-COO-C(CH3)2CH2-SO3H) and its salts, n-butyl sulfonic acid methacrylate (CH2C(CH3)-COO-(CH2)4-SO3H) and its salts, phenylene sulfonic acid methacrylate (CH2C(CH3)-COO-C6H4-SO3H) and its salts, naphthalene sulfonic acid methacrylate (CH2C(CH3)-COO-C 10 Examples include H8-SO3H and its salts. Copolymers containing two or more of these are also acceptable. The salts may be sodium salts, potassium salts, or other salts that do not interfere with polymerization.

[0046] Known initiators may be used. For example, one or more selected from the group consisting of azobis compounds, organic peroxides, inorganic peroxides, and redox initiator systems are exemplified. Benzoyl peroxide is an example of an organic peroxide. Sodium persulfate is an example of an inorganic peroxide. Examples of redox initiator systems include combinations of azobis compounds, organic peroxides, inorganic peroxides, etc., with amines, etc.

[0047] Examples of initiators that may be used include 4,4'-azobis(4-cyanovaleric acid), sodium peroxodisulfate, 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine]n hydrate, 2,2'-azobis(isobutyronitrile), and 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide].

[0048] The initiator content may be 0.01 to 1 part by weight, preferably 0.05 to 0.5 parts by weight, per 100 parts by weight of anionic group-containing polymerizable monomer.

[0049] Other components may be added to the polymerization reaction system. For example, chain transfer agents such as alcohols, mercaptans, and halogenated carbons may be added. If RAFT polymerization is used, a RAFT agent may be further included.

[0050] The solvent in the polyanion generation step may be water. In particular, purified water such as distilled water or ion-exchanged water may be used. The solvent may further contain organic solvents such as alcohol. The solvent content may be 100 to 2000 parts by weight, preferably 500 to 1000 parts by weight, per 100 parts by weight of the anion group-containing polymerizable monomer.

[0051] Various post-treatments may be performed as needed during and / or after the polyanion generation stage. For example, pressure manipulation (e.g., depressurization and / or repressurization), temperature control (e.g., heating and / or cooling), and / or ion exchange treatment (e.g., cation ion exchange resin treatment and / or anion ion exchange resin treatment) may be performed as post-treatments.

[0052] Next, the polythiophene generation step is performed in S200. In the polythiophene generation step, cationic thiophene may be polymerized in a solution containing the polyanion generated in S100 to produce cationic polythiophene that forms a conductive composite with the polyanion.

[0053] For example, a cationic polythiophene may be produced by mixing and stirring a polyanion, a cationic thiophene, an oxidizing agent, a catalyst, and a solvent at a constant temperature (e.g., 10-50°C). Furthermore, if necessary, an acid solution and at least one other additive may be added to the reaction system to proceed with chemical oxidative polymerization.

[0054] Cationic thiophenes may be, for example, unsubstituted thiophenes or thiophenes substituted with one or more substituents. Substituents may include, for example, C1-C10 alkyl groups, C4-C20 aryl groups, halogen groups, alcohol groups, hydroxyl groups, alkoxy groups, carboxyl groups, carbonyl groups, ether groups, alkyldioxy groups, or alkoxycarbonyl groups.

[0055] As an example, cationic thiophenes include thiophene, 3-methylthiophene, 3-ethylthiophene, 3-propylthiophene, 3-butylthiophene, 3-hexylthiophene, 3-heptylthiophene, 3-octylthiophene, 3-decylthiophene, 3-dodecylthiophene, 3-octadecylthiophene, 3-bromothiophene, 3-chlorothiophene, 3-iodothiophene, 3-cyanothiophene, 3-phenylthiophene, 3,4-dimethylthiophene, 3,4-dibutylthiophene, 3-hydroxythiophene, 3-methoxythiophene, 3-ethoxythiophene, 3-butoxythiophene, 3-hexyloxythiophene, 3-heptyloxythiophene, 3-octyloxythiophene, 3-decyloxythiophene, 3-dodecyloxythiophene, and 3-octadecyloxythiophene. The polythiophene may be one or more of the following: thiophene, 3,4-dihydroxythiophene, 3,4-dimethoxythiophene, 3,4-diethoxythiophene, 3,4-dipropoxythiophene, 3,4-dibutoxythiophene, 3,4-dihexyloxythiophene, 3,4-diheptyloxythiophene, 3,4-dioctyloxythiophene, 3,4-didecyloxythiophene, 3,4-didodecyloxythiophene, 3,4-ethylenedioxythiophene, 3,4-propylenedioxythiophene, 3,4-butylenedioxythiophene, 3-methyl-4-methoxythiophene, 3-methyl-4-ethoxythiophene, 3-carboxythiophene, 3-methyl-4-carboxythiophene, 3-methyl-4-carboxyethylthiophene, and 3-methyl-4-carboxybutylthiophene. The cationic polythiophene may be ethylenedioxythiophene (EDOT) in particular.

[0056] The solvent in the polythiophene production step may be water. In particular, purified water such as distilled water or ion-exchanged water may be used. The solvent may also contain organic solvents.

[0057] The oxidizing agent may be sodium persulfate or ammonium persulfate. The catalyst may be an iron catalyst, such as Fe2(SO4)3, FeCl2, FeCl3, or hydrates thereof.

[0058] The content of cationic thiophene may be 0.1 to 10 parts by weight per 100 parts by weight of polyanion. The content of oxidizing agent may be 10 to 100 parts by weight per 100 parts by weight of polyanion. The content of catalyst may be 10 to 100 parts by weight per 100 parts by weight of polyanion. The content of solvent may be 50 to 1000 parts by weight per 100 parts by weight of polyanion.

[0059] Next, in S300, a termination step is performed to stop the polymerization reaction in the polythiophene generation step. The method of performing the termination step is not particularly limited, but it may be done by removing ions in the polymerization reaction. For example, the termination step may be performed by adding an ion exchange resin to the solution during the reaction.

[0060] The ion exchange resin used in the termination stage may be either a cation exchange resin or an anion exchange resin, or both. From the viewpoint of sufficiently removing both cations and anions from the polymerization reaction, it is preferable to use both a cation exchange resin and an anion exchange resin.

[0061] As the cation exchange resin, any known resin may be used, for example, a polymer obtained by introducing a sulfo group into a copolymer of styrene and divinylbenzene may be used. As the anion exchange resin, any known resin may be used, for example, a polymer obtained by introducing N-methylmethaneamine (also known as dimethylamine) into a chloromethylated styrene-divinylbenzene copolymer, or a polymer obtained by introducing polyethylene polyamine may be used. Chelate resins may also be used as the cation exchange resin and / or anion exchange resin.

[0062] At the discontinuation stage, anion exchange resin may be used in an amount of 100 to 2000 parts by weight per 100 parts by weight of solid content of the conductive composite. At the discontinuation stage, cation exchange resin may be used in an amount of 100 to 2000 parts by weight per 100 parts by weight of solid content of the conductive composite.

[0063] After stopping the reaction with an ion exchange resin, the ion exchange resin is removed. Furthermore, the amount of solids may be adjusted by adding a solvent to the solution. For example, ultrapure water may be added to the solution.

[0064] Next, in S400, a high-pressure emulsification step is performed in which the conductive composite obtained in S300 is emulsified under high pressure. The high-pressure emulsification treatment may be carried out using a pressure homogenizer or an ultrasonic homogenizer. For example, the high-pressure emulsification treatment may be performed by passing the liquid through a high-pressure emulsifier such as a pressure homogenizer at a pressure of 100 to 1500 Bar one to several times (e.g., 10 times). By loosening the conductive composite and lowering its viscosity through the high-pressure emulsification treatment, contact between the conductive composite and the ion exchange resin can be promoted in the subsequent purification step. The high-pressure emulsification step may be omitted.

[0065] Next, in step S500, a purification step is performed in which the conductive composite is purified using an ion exchange resin. In the purification step, the ion exchange resin may contain at least a cation exchange resin. The ion exchange resin may further contain an anion exchange resin. From the viewpoint of sufficiently removing both cations and anions from the polymerization reaction, it is preferable to use both a cation exchange resin and an anion exchange resin. The cation exchange resin and anion exchange resin may be those described in the termination step.

[0066] In the purification stage, anion exchange resin may be used in an amount of 100 to 2000 parts by weight per 100 parts by weight of solid content of the conductive composite. In the purification stage, cation exchange resin may be used in an amount of 100 to 2000 parts by weight per 100 parts by weight of solid content of the conductive composite. The amount of ion exchange resin used in the purification stage (also called "first ion exchange resin") may be 10 to 200 parts by weight per 100 parts by weight of ion exchange resin used in the termination stage (also called "second ion exchange resin").

[0067] By using an ion exchange resin in the termination stage and then performing purification again with an ion exchange resin in the purification stage, the ionic components contained in the conductive composite can be reduced. Furthermore, the effect of the purification stage can be further enhanced by performing a high-pressure emulsification stage. For example, according to this embodiment, the SO4 ion concentration can be set to 1,400 PPM or less, and the Fe ion concentration can be set to 300 PPM or less.

[0068] Next, in S510, a powdering step is performed in which the conductive composite is subjected to a drying treatment to turn it into powder. Powdering may be carried out by using a spray dryer to evaporate the solvent (e.g., water) in the conductive composite solution by drying while spraying. This can increase the efficiency of powder production. The outlet temperature of the spray dryer is preferably 35°C to 100°C, and more preferably 50°C to 70°C. If the temperature is too low, the drying of the solvent will be too slow, and if the temperature is too high, there is a risk of over-drying.

[0069] Next, in S520, a coating composition is prepared from the purified and powdered conductive composite. The powdered conductive composite may be mixed with a solvent (for example, ultrapure water, or an alcohol having 1 to 5 carbon atoms such as methanol, ethanol, or isopropyl alcohol) and recovered as a composition containing a polyanion and a cationic polythiophene that forms a conductive composite with the polyanion. If necessary, additives (for example, dispersants, conductive agents, etc.) may be added to the composition separately.

[0070] As a dispersant used as an additive, trioctylamine (TOA), triethylamine (TEA), or other known dispersants may be used.

[0071] The NV value (non-volatile content) of the composition may be 10% by mass or less, or 5% by mass or less, and the lower limit should be such that the composition exhibits conductivity. Preferably, it may be 0.005 to 2% by mass, and as an example, it may be 1.2% by mass. S520 may be omitted, in which case the obtained powder may be recovered as is as a composition.

[0072] Next, in step S600, the composition obtained in step S500 is coated onto the substrate and dried to produce an antistatic film. The substrate may be a transparent resin film such as a PET substrate or a glass film. When the composition (for example, a solution-like composition with an NV value of 1.2% by mass) is coated onto a PET substrate to a dry film thickness of 0.1 μm, the surface resistivity can be set to 10,000 to 1,000,000 Ω / sq. The NV value (non-volatile content) may be measured using an Agilent Mark3.

[0073] As described above, according to the manufacturing method flow of this embodiment, a composition containing a polyanion and a cationic polythiophene that forms a conductive composite with the polyanion can be produced, and the Fe ion concentration and SO4 ion concentration of the composition can be reduced. This makes it possible to improve the conductivity and dispersibility of the composition.

[0074] [Examples] Examples are shown below, but this embodiment is not limited to these examples.

[0075] (Manufacturing Example 1) (Polythiophene production) A mixture was obtained by mixing 6 g of 3,4-ethylenedioxythiophene with 180 g of an aqueous solution of polystyrene sulfonic acid obtained by radical polymerization (solid content 10%, GPC-Mw 200,000, molecular weight dispersion degree 2.2) and 900 g of water. An aqueous solution of ferric sulfate was obtained by dissolving 3.6 g of ferric sulfate in 64 g of water. The aqueous solution of ferric sulfate was added to the mixture while stirring. The mixture was maintained at 30°C during stirring.

[0076] Next, 13.2 g of sodium persulfate was dissolved in 115 g of water to obtain an aqueous solution of ammonium persulfate. The aqueous solution of ammonium persulfate was added to the mixture. The mixture was then stirred for 4 hours to allow the reaction to occur, and a reaction solution was obtained. The reaction solution contained 6 g of EDOT and 18 g of PSS as solid components.

[0077] 160 g of cation exchange resin (Duolite C255LFH, manufactured by Sumika Chemtex Co., Ltd.) and 160 g of anion exchange resin (Duolite A368MS, manufactured by Sumika Chemtex Co., Ltd.) were added to the reaction solution and stirred for 2 hours, followed by standing for 12 hours to stop the reaction. The cation exchange resin and anion exchange resin were then removed by filtration, and water was added to achieve a solid content of 1.2%. Further dispersion treatment was performed at 1200 Bar using a high-pressure emulsifier to obtain a raw material liquid containing the composite and water.

[0078] (Manufacturing example 2) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, an additional 80g of cation exchange resin and 80g of anion exchange resin were added during the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0079] (Manufacturing Example 3) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, an additional 160g of cation exchange resin and 160g of anion exchange resin were added during the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0080] (Manufacturing example 4) The raw material solution was obtained in the same manner as in Production Example 1, except that the aqueous polystyrene sulfonic acid solution (solid content 10%, GPC-Mw 200,000, molecular weight dispersion degree 2.2) was replaced with an aqueous polystyrene sulfonic acid solution obtained by radical polymerization (solid content 10%, GPC-Mw 300,000, molecular weight dispersion degree 2.3).

[0081] (Manufacturing example 5) The raw material liquid was obtained in the same manner as in Production Example 4, except that after dispersion treatment with a high-pressure emulsifier, an additional 80g of cation exchange resin and 80g of anion exchange resin were added during the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0082] (Manufacturing example 6) The raw material liquid was obtained in the same manner as in Production Example 4, except that after dispersion treatment with a high-pressure emulsifier, an additional 160g of cation exchange resin and 160g of anion exchange resin were added during the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0083] (Manufacturing example 7) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, only 40 g of cation exchange resin was added in the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0084] (Manufacturing example 8) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, only 20 g of cation exchange resin was added in the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0085] (Manufacturing example 9) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, only 40 g of anion exchange resin was added in the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0086] (Manufacturing example 10) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, only 20 g of anion exchange resin was added in the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0087] (Manufacturing Example 11) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, an additional 80 g of cation exchange resin was added during the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0088] (Manufacturing Example 12) The raw material liquid was obtained in the same manner as in Production Example 1, except that after dispersion treatment with a high-pressure emulsifier, only 160 g of cation exchange resin was added in the purification stage, stirred for 1 hour, and then the ion exchange resin was removed by filtration.

[0089] (Manufacturing Example 13) While stirring 500g of the raw material solution obtained in Production Example 3, 10g of a 1wt% sodium carbonate aqueous solution was slowly added and stirred for 1 hour to obtain the raw material solution for Production Example 13.

[0090] (Manufacturing Example 14) While stirring 500g of the raw material solution obtained in Production Example 3, 2g of 1wt% ferrous sulfate aqueous solution was slowly added and stirred for 1 hour to obtain the raw material solution for Production Example 14.

[0091] (Comparative Example 1) 300g of the raw material liquid obtained in Production Example 1 was spray-dried using a spray dryer (BUCHI, B-290) at an inlet temperature of 110°C, an outlet temperature of 60°C, and a spray rate of 180g / hr to obtain a dried powder (yield 90%). 0.5g of the dried powder was added to 75g of isopropyl alcohol (IPA) and pre-dispersed for 15 minutes using an ultrasonic homogenizer. Next, 0.5g of trioctylamine (TOA) was added and dispersion mixing was continued for 15 minutes using an ultrasonic homogenizer. After that, the mixture was passed through a high-pressure emulsifier five times at 1200 Bar, and then 75g of IPA was added to dilute it 2-fold and obtain a dispersion.

[0092] (Example 1) Except for using the raw material liquid prepared in Preparation Example 2 instead of Preparation Example 1, a dried powder was obtained in the same manner as in Comparative Example 1. When the dried powder was observed by SEM at a magnification of 3000x, the particle size was approximately micron size (0.3-7 μm). A dispersion was then prepared using the obtained dried powder.

[0093] (Example 2) Except for using the raw material liquid produced in Production Example 3 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0094] (Comparative Example 2) Except for using the raw material liquid produced in Production Example 4 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0095] (Example 3) Except for using the raw material liquid produced in Production Example 5 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0096] (Example 4) Except for using the raw material liquid produced in Production Example 6 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0097] (Example 5) Except for using the raw material liquid produced in Production Example 7 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0098] (Example 6) Except for using the raw material liquid produced in Production Example 8 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0099] (Example 7) Except for using the raw material liquid produced in Production Example 9 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0100] (Example 8) Except for using the raw material liquid produced in Production Example 10 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0101] (Example 9) Except for using the raw material liquid produced in Production Example 11 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0102] (Example 10) Except for using the raw material liquid produced in Production Example 12 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0103] (Example 11) Except for using the raw material liquid produced in Production Example 13 instead of Production Example 1, a dried powder was obtained in the same manner as in Comparative Example 1, and then a dispersion was produced.

[0104] (Comparative Example 3) Except for using the raw material liquid produced in Production Example 14 instead of Production Example 1, we attempted to obtain a dried powder in the same manner as in Comparative Example 1 and then produce a dispersion, but sufficient dispersibility was not achieved.

[0105] (ICP-MS analysis) In each example and comparative example, a portion of the dried powder obtained midway through the process was adjusted to a 1.2 wt% solution with ultrapure water. To this solution, 5 g of highly concentrated dilute nitric acid was added, and the solution was subjected to thermal decomposition treatment using a microwave for 1 hour to obtain decomposed water.

[0106] After cooling the decomposition treatment water, the decomposition of polymer components in the liquid was confirmed. The decomposition treatment water was diluted with 1% nitric acid containing an internal standard (Indium) as a masterbatch, and the total volume of the liquid was adjusted to approximately 50g (internal standard concentration In 1 ppb) to obtain a diluted solution. The diluted solution was introduced into an ICP-MS (Agilent 8900). High-purity argon was used as the plasma gas, and hydrogen was used as the auxiliary gas. The measured concentrations of Na ions and Fe ions were calculated by converting them to the dilution ratio (approximately 250 times). In Tables 1 and 2 below, the measured concentrations of Na ions and Fe ions are expressed as weight ratios in parts per million (PPM) relative to the conductive composite.

[0107] (IC analysis) The 1.2% solutions of each example and comparative example used in ICP-MS analysis were further diluted 10-fold with ultrapure water, and the resin components were removed and separated using a dialysis membrane filter. The ultrapure water from which the resin components had been removed was introduced into a JASCO HPLC system, and the SO4 ion concentration was measured. An SI-90 4E column (Shodex) was used. The measured SO4 ion concentration values ​​were converted to the dilution ratio. In Tables 1 and 2 below, the measured SO4 ion concentration values ​​are expressed as a weight ratio in parts per million (PPM) relative to the conductive composite.

[0108] (Confirmation of sediment) Each dispersion obtained in the examples and comparative examples was left to stand at room temperature overnight. After standing, the bottom of the container bottle of the dispersion was observed to check for the presence or absence of sediment.

[0109] (Surface resistivity) Each dispersion obtained in the examples and comparative examples was applied to a PET film using a bar coater No. 4 and dried at 105°C for 1 minute. The surface resistivity of the coated surface of the dried film was measured using a surface resistivity meter (Mitsubishi Chemical Analytics: Loresta).

[0110] (Hayes) The haze value of the clean portion of the film obtained by surface resistivity measurement was measured using a HAZE meter (Nippon Denshoku: NDH-5000).

[0111] The measurement and observation results for each example and comparative example are shown in the following tables. As shown in Tables 1 and 2, Comparative Examples 1 and 2, which did not undergo the purification step, had higher ion concentrations compared to the examples, resulting in poorer dispersibility. Specifically, these comparative examples had more precipitate, higher surface resistivity, and slightly higher haze compared to the examples.

[0112] In Examples 7 and 8, where only anion exchange resin was used in the purification stage, the SO4 ion concentration was lower than in Comparative Examples 1 and 2, but the cation concentration was higher than in the other examples. As a result, while the haze in Examples 7 and 8 was superior to that of Comparative Examples 1 and 2, the state of the precipitate and the surface resistivity were inferior to those of the other examples.

[0113] The effects of Fe ion concentration and Na ion concentration were confirmed by comparing Examples 2, 11, and Comparative Example 3. Example 11 was obtained by adding Na ions afterwards, as in Example 2. As a result, in Example 11, the Na ion concentration increased significantly compared to Example 2, and although the surface resistivity and haze worsened slightly, it was within an acceptable range. Comparative Example 3 was obtained by adding Fe ions afterwards, as in Example 2. As a result, in Comparative Example 3, the Fe ion concentration increased significantly compared to Example 2, resulting in more precipitate and a significant deterioration in surface resistivity and haze.

[0114] Thus, while the Na ion concentration did not significantly affect the amount of precipitate, surface resistivity, and haze, the Fe ion concentration did significantly affect these factors. This embodiment demonstrates that by setting the Fe ion concentration to 300 PPM or less, the amount of precipitate can be reduced, dispersibility improved, and surface resistivity and haze can be improved.

[0115] [Table 1] [Table 2]

[0116] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. Furthermore, within the scope that does not contradict the technical aspects, matters described for a particular embodiment can be applied to other embodiments. In addition, each component may have the same name but different reference numerals as other components. It will be clear from the claims that such modified or improved forms may also be included within the technical scope of the present invention.

[0117] It should be noted that the execution order of operations, procedures, steps, and stages in the apparatus, systems, programs, and methods shown in the claims, specifications, and drawings is not explicitly stated as "before," "prior to," etc., and that these can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," "next," etc. for convenience, it does not mean that it is essential to perform the operations in that order. [Explanation of Symbols]

[0118] 10 Antistatic film 110 Transparent base material 120 Antistatic layer

Claims

1. A polythiophene generation step involves polymerizing a cationic thiophene in a polyanion to produce a cationic polythiophene that forms a conductive composite with the polyanion, A termination step in which the polymerization reaction in the polythiophene production step is stopped, Following the aforementioned termination step, a purification step is performed in which the conductive composite is purified with a first ion exchange resin. Equipped with, A method for manufacturing conductive composites.

2. The first ion exchange resin includes a cation exchange resin. A method for producing a conductive composite according to claim 1.

3. In the purification step, the cation exchange resin is used in an amount of 100 to 2000 parts by weight per 100 parts by weight of the solid content of the conductive composite. A method for producing a conductive composite according to claim 2.

4. The first ion exchange resin further comprises an anion exchange resin. A method for producing a conductive composite according to claim 2.

5. In the purification step, the anion exchange resin is used in an amount of 100 to 2000 parts by weight per 100 parts by weight of the solid content of the conductive composite. A method for producing a conductive composite according to claim 4.

6. The process further comprises a high-pressure emulsification step, which involves emulsifying the conductive composite under high pressure, after the aforementioned termination step and before the aforementioned purification step. A method for producing a conductive composite according to claim 1.

7. The aforementioned termination step is performed by removing ions from the polymerization reaction using a second ion exchange resin. A method for producing a conductive composite according to claim 1.

8. The amount of the first ion exchange resin used in the purification step is 10 to 200 parts by weight relative to 100 parts by weight of the second ion exchange resin used in the termination step. A method for producing a conductive composite according to claim 7.

9. The aforementioned polyanion is polystyrene sulfonic acid (PSS). A method for producing a conductive composite according to claim 1.

10. The cationic polythiophene is polyethylenedioxythiophene (PEDOT). A method for producing a conductive composite according to claim 1.

11. The aforementioned polyanion is a monopolymer. A method for producing a conductive composite according to claim 1.

12. The present invention comprises a polyanion containing a sulfonic acid group with a weight-average molecular weight of 50,000 to 1,000,000, and a cationic polythiophene that forms a conductive composite with the polyanion. SO for the conductive composite ４ The ion concentration is 1,400 PPM or less. composition.

13. The Fe ion concentration in the conductive composite is 100 PPM or less. The composition according to claim 12.

14. The aforementioned polyanion is polystyrene sulfonic acid (PSS). The composition according to claim 12.

15. The cationic polythiophene is polyethylenedioxythiophene (PEDOT). The composition according to claim 14.

16. The aforementioned polyanion is a monopolymer. The composition according to claim 12.

17. The composition according to claim 12, wherein the composition is in powder form, and the particle size of the powder is 0.3 μm or more and 30 μm or less.

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