Antistatic agent using conductive polymer compound

Abstract

The present invention addresses the problem of providing a composition for producing an antistatic film that has high antistatic characteristics. Provided is a composition for an antistatic agent, which contains an amine compound and a conductive polymer compound that has a phosphonic acid site and / or a phosphoric acid site, wherein: the amine compound is a secondary amine or a tertiary amine; the amine compound has one or two alkyl groups having 4 or more carbon atoms; and the total number of carbon atoms in the alkyl groups in the amine compound is 5 to 9. The conductive polymer compound preferably has a structural unit of formula (13).

Description

Antistatic agent using conductive polymer compound

[0001] The present invention relates to an antistatic composition containing a conductive polymer of a specific structure and a specific amine compound, and an antistatic agent using the same.

[0002] Antistatic agents containing conductive polymers have been developed and used in the past. Patent Document 1 discloses an antistatic treatment agent containing a conductive polymer and an amine compound. Patent Document 2 discloses an antistatic treatment agent containing a conductive polymer and a fluorinated aliphatic amine compound. Patent Document 3 discloses a polythiophene compound having high conductivity. However, there are cases where antistatic properties higher than those of conventional antistatic agents are preferred, and the development of a material with even higher antistatic properties has been desired.

[0003] In the lithography process for forming semiconductor integrated circuits and photomasks, electron beam writing is performed on a semiconductor surface such as a silicon wafer or a glass substrate coated with resist. When the electron beam strikes the resist, the resist tends to become charged. Charging the resist causes distortion of the electron beam, resulting in misalignment of the drawn circuit. For this reason, it has been common practice to coat the resist surface with an antistatic film.

[0004] Here, when performing electron beam lithography, the higher the current value of the electron beam, the more minute the circuit can be written in a shorter time, so it is preferable to perform electron beam lithography at a high current value.

[0005] However, the higher the electron beam current during electron beam lithography, the greater the tendency for the resist to become charged during electron beam lithography. Therefore, in order to accurately lithograph even when the electron beam current is high, an antistatic film with a higher antistatic effect is required. For these reasons, an antistatic film with even better antistatic properties has been desired.

[0006] Resists are also classified into chemically amplified resists and non-chemically amplified resists, with chemically amplified resists containing photoacid generators for acid-catalyzed reactions. On the other hand, non-chemically amplified resists contain compounds with functional groups that absorb and react with light. As such, chemically amplified resists and non-chemically amplified resists have different material compositions, resulting in different surface properties. Therefore, it is difficult for conventional antistatic agents to achieve both film-forming properties on the surface of chemically amplified resists and non-chemically amplified resists.

[0007] JP 2006-117925 JP 2004-099678 WO 2022 / 260007

[0008] An object of the present invention is to provide an antistatic agent having high antistatic properties.

[0009] As a result of extensive research, the present inventors have found that the above object can be achieved by a composition containing a conductive polymer and a specific amine compound, and have thus completed the present invention.

[0010] That is, the present invention provides the following compositions, etc.

[0011] (Item 1) An antistatic composition comprising a conductive polymer compound having a phosphonic acid moiety and / or a phosphoric acid moiety and an amine compound, wherein the amine compound is a secondary amine or a tertiary amine, has one or two alkyl groups having 4 or more carbon atoms, and has a total of 5 to 9 carbon atoms.

[0012] (Item 2) An antistatic agent used as a material in a method for forming an antistatic film on the surface of an article, wherein the antistatic agent is an aqueous solution and comprises the antistatic agent composition described in Item 1 above.

[0013] (Item 3) The antistatic agent according to item 2, wherein the article is a circuit board having a resist as a surface layer.

[0014] (Item 4) An antistatic agent for forming an antistatic film on the surface of an article, wherein the antistatic agent is a solid and comprises the antistatic agent composition described in item 1 above.

[0015] (Item 5) The antistatic composition according to item 1, wherein the amine compound does not have a primary amino group.

[0016] (Item 6) The antistatic composition according to item 1 or 5 (for example, item 1) above), wherein the amine compound is an aliphatic amine compound.

[0017] (Item 7) The antistatic agent composition according to any one of Items 1, 5, and 6 (e.g., Item 1) above), wherein the amine compound has one amino group, which is a secondary amino group or a tertiary amino group, and the alkyl group is a chain alkyl group.

[0018] (Item 8) The antistatic composition according to any one of Items 1 and 5 to 7 (for example, Item 1) above, wherein the total number of carbon atoms in the amine compound is 8 or 9.

[0019] (Item 9) The antistatic agent composition according to any one of Items 1 and 5 to 8 (for example, Item 1) above), wherein the alkyl group is a chain alkyl group having 4 to 6 carbon atoms.

[0020] (Item 10) The amine compound contains two butyl groups, or the amine compound contains one C ５ ~C ８ 10. The antistatic composition according to any one of items 1 and 5 to 9 (for example, item 1), which contains an alkyl group.

[0021] (Item 11) The antistatic agent composition according to any one of Items 1 and 5 to 10 (for example, Item 1) above), wherein the amine compound is selected from di-n-butylamine, N,N-dimethylhexylamine, and N-methyldibutylamine.

[0022] (Item 12) The antistatic agent composition according to any one of Items 1 and 5 to 11 (e.g., Item 1) above), wherein the conductive polymer compound is a polythiophene compound having a structure in which a 1,4-dioxane ring is condensed with a thiophene ring, and wherein the substituent having the phosphonic acid moiety and / or phosphoric acid moiety is bonded to the 1,4-dioxane ring.

[0023] (Item 13) The conductive polymer compound is represented by the following formula (13): 14. The antistatic composition according to any one of items 1 and 5 to 13 (for example, item 1), comprising a repeating unit represented by the following formula:

[0024] (Item 14) An antistatic film containing the antistatic agent according to item 4 above.

[0025] (Item 15) An article having a substrate and a coating present on the surface of the substrate, wherein the coating is the antistatic film according to item 14 above.

[0026] (Item 16) A method for producing an article having antistatic properties, comprising the step of applying the antistatic agent according to item 2 or 3 onto a substrate to form an antistatic film.

[0027] The compositions of the present invention achieve high antistatic properties.

[0028] Fig. 1 shows a pattern drawn on a resist substrate in an example. Fig. 2A is an optical microscope photograph of a pattern drawn on a resist substrate having an antistatic film with good antistatic performance. Fig. 2B is an optical microscope photograph of a pattern drawn on a resist substrate having an antistatic film with poor antistatic performance.

[0029] The present invention will be described in detail below.

[0030] (Antistatic Composition) The antistatic composition of the present invention contains a conductive polymer compound having a phosphonic acid moiety and / or a phosphoric acid moiety and an amine compound.

[0031] (Conductive polymer compound) As the conductive polymer compound, a known conductive polymer compound having a phosphonic acid moiety and / or a phosphoric acid moiety can be used. Preferably, it has a phosphonic acid moiety, and more preferably, it has a phosphonic acid moiety but does not have a phosphoric acid moiety. For example, it may be a polythiophene compound having a phosphonic acid moiety, or a polyaniline compound having a phosphonic acid moiety. A polythiophene compound is preferred.

[0032] The polythiophene compound is preferably a compound having a structure in which a 1,4-dioxane ring is condensed with a thiophene ring. In a more preferred embodiment, the polythiophene compound has a structure in which a substituent having a phosphonic acid moiety is bonded to the 1,4-dioxane ring.

[0033] As the polythiophene compound, for example, the polythiophene compounds described in WO 2022 / 260007 (Patent Document 3) can be used. Preferred polythiophene compounds are described below.

[0034] [Polythiophene Compound] The polythiophene compound is represented by, for example, general formula (12): -(A) ｑ - (12) where each A is independently a thiophene monomer residue. q is the degree of polymerization and is an arbitrary positive integer. Specifically, it can be, for example, 3 or more, 6 or more, or 10 or more, and can be 2,000 or less, 1,000 or less, 800 or less, or 400 or less.

[0035] When the structure of a polythiophene compound is described as a general formula, both terminals are generally omitted, and therefore, in this specification, both terminals are also omitted as a general rule when describing the structure of a polythiophene compound. However, for example, if both terminal groups are intentionally written in the above general formula (12), the following general formula (12A) is obtained.

[0036] E １ -(A) ｑ -E ２ (12A) where E １ and E２ are terminal groups. Usually, one is a polymerization initiation terminal and the other is a polymerization termination terminal.

[0037] The polythiophene compound is preferably a homopolymer. However, if desired, the polythiophene compound may be a copolymer. The copolymer may be a block copolymer or a random copolymer.

[0038] In this specification, a unit constituting the repeating structure of a polymer is referred to as a structural unit. That is, in the polymer of the above general formula (12A), "A" is a structural unit, and the polymer is composed of the structural unit and the terminal group. In other words, the portion of the polymer other than the polymerization initiation end and polymerization termination end is composed of the structural unit. Therefore, in this specification, the statement "the polythiophene compound does not contain any structural unit other than the general formula (A)" means that the portion other than the terminal group is composed only of the structural unit of the general formula (A). A preferred polythiophene compound contains a structural unit represented by the following general formula (A):

[0039]

[0040] In the general formula (A), L is a group represented by the formula (21): It is expressed as:

[0041] Here, R ５ are independently a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. ６ are independently a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom.

[0042] n １ is 0 or 1, preferably 0. ２ are independently an integer of 1 to 6, preferably 1 to 4, more preferably 1 or 2, and even more preferably 1. ３is independently 0 or 1, preferably 0. ３ If is 0, then n ４ is preferably 1 or 2, and n ４ It is more preferable that n is 1. ４ is an integer of 0 to 12, preferably 0 to 6, more preferably 1 or 2, and even more preferably 1. ２ and ４ The product of these is the total number of carbon atoms between the dioxane ring and the phosphorus. (Number of carbon atoms between the dioxane ring and the phosphorus) = n ２ ×n ４ The number of carbon atoms between the dioxane ring and the phosphorus is preferably 1 to 12, more preferably 1 to 9, even more preferably 1 to 6, particularly preferably 1 to 3, and in one embodiment, 1 or 2.

[0043] The left end of formula (21) is bonded to the carbon atom in the dioxane ring in formula (A), and the right end of formula (21) is bonded to the phosphorus atom in formula (A).

[0044] In one embodiment, R ５ and R ６ is a hydrogen atom, and n １ is 0, and n ３ is 0, and n ４ is 1. That is, in this embodiment, L is -(CH ２ ) ｎ２ -, where n ２ are independently 0 to 12. ２ is preferably 0 to 4, more preferably 0 to 2. It is particularly preferably 1.

[0045] M １ and M ２ are each independently an alkyl group having 1 to 15 carbon atoms or a hydrogen atom. １ and M ２ At least one of M is a hydrogen atom, and more preferably １ and M ２ are both hydrogen atoms.

[0046] In general formula (A), R １Ａ is a hydrogen atom, an alkyl group, an alkoxy group, an acyl group, or a group represented by formula (15), preferably an alkyl group or a hydrogen atom, more preferably a hydrogen atom. Here, L １ is expressed by the formula (22): It is expressed as:

[0047] Here, R １５ are independently a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom.

[0048] R １６ are independently a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom.

[0049] m １ is 0 or 1, preferably 0.

[0050] m ２ are independently an integer of 1 to 6, preferably 1 to 4, more preferably 1 or 2, and even more preferably 1.

[0051] m ３ is independently 0 or 1, preferably 0. ３ If is 0, then m ４ is preferably 1 or 2, and m ４ It is more preferable that the value of .times. ...

[0052] m ４ is an integer of 0 to 12, preferably 0 to 6, more preferably 1 or 2, and even more preferably 1.

[0053] m ２ and m ４ The product of these is the total number of carbon atoms between the dioxane ring and the phosphorus. (Number of carbon atoms between the dioxane ring and the phosphorus) = m ２ ×m ４

[0054] The number of carbon atoms between the dioxane ring and the phosphorus is preferably 1 to 12, more preferably 1 to 9, even more preferably 1 to 6, particularly preferably 1 to 3, and in one embodiment, 1 or 2.

[0055] In addition, the number of carbon atoms between the dioxane ring and phosphorus in L and L １ The total number of carbon atoms between the dioxane ring and the phosphorus in the formula (I) is preferably 1 to 16, more preferably 1 to 12, even more preferably 1 to 8, particularly preferably 1 to 4, and in one embodiment, 1 or 2.

[0056] The left end of formula (22) is bonded to the carbon atom in the dioxane ring in formula (A), and the right end of formula (22) is bonded to the phosphorus atom in formula (15).

[0057] In one embodiment, R 1５ and R 1６ is a hydrogen atom, and m １ is 0, and m ３ is 0, and m ４ is 1. That is, in this embodiment, L １ is -(CH ２ ) ｍ２ -, where m ２ are independently 0 to 12. １ｃ and M ２ｃ are each independently an alkyl group having 1 to 15 carbon atoms or a hydrogen atom.

[0058] In this specification, the phosphoric acid or phosphonic acid moiety refers to a moiety having a structure of a phosphoric acid group or a derivative thereof (e.g., a salt or an ester), or a phosphonic acid group or a derivative thereof (e.g., a salt or an ester). For example, a phosphoric acid group or a phosphonic acid group may be provided with M of the general formula (A): １ and M ２ or a phosphate group or a phosphonate group, １ｃ and M ２ｃ The site to which is bound is also referred to herein as a phosphate or phosphonate site.

[0059] In general formula (A), R １Ａ The alkyl groups in the formula (I) may each independently be linear, branched, or cyclic. A cyclic alkyl group may consist solely of a cyclic structure, or may have a structure in which a linear alkyl group is further bonded to a cyclic structure. The alkyl group preferably has 1 to 15 carbon atoms, more preferably 1 to 8, and particularly preferably 1 to 4. Specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, and a pentadecyl group.

[0060] R １Ａ The alkoxy groups in the formula (I) may each independently be linear, branched, or cyclic. The cyclic alkoxy group may consist solely of a cyclic structure, or may have a structure in which a chain alkyl group and / or a chain alkoxy group is further bonded to the cyclic structure. The number of carbon atoms in the alkoxy group is preferably 1 to 15, more preferably 1 to 8, and particularly preferably 1 to 4. Specific examples include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, a dodecyloxy group, a tridecyloxy group, a tetradecyloxy group, and a pentadecyloxy group.

[0061] R １Ａ The acyl groups in the formula (I) may each independently be linear, branched, or cyclic. The cyclic acyl group may consist of only a cyclic structure, or may have a structure in which a chain alkyl group and / or a chain acyl group is further bonded to the cyclic structure. The number of carbon atoms in the acyl is preferably 1 to 15, more preferably 1 to 8, and particularly preferably 1 to 4. Specific examples include an acetyl group, a propionyl group, a butanoyl group, a pentanoyl group, a hexanoyl group, a heptanoyl group, an octanoyl group, a nonanoyl group, a decanoyl group, an undecanoyl group, a dodecanoyl group, a tridecanoyl group, a tetradecanoyl group, and a pentadecanoyl group.

[0062] In one preferred embodiment, R １Ａ is a hydrogen atom.

[0063] M １ and M ２ may be the same or different from each other. In one preferred embodiment, M １ and M ２ are the same. １ｃ and M ２ｃ may be the same or different from each other. In one preferred embodiment, M １ｃ and M ２ｃ are identical.

[0064] In the above general formula (A), M １ and M ２ and M １ｃ and M ２ｃ The alkyl group in may be either linear or branched, and preferably has 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms. In a more preferred embodiment, the alkyl group has 2 carbon atoms. When the number of carbon atoms in the alkyl group is within the preferred range, a polythiophene compound with good conductivity can be obtained. Specific examples include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, and pentadecyl groups.

[0065] In the above general formula (A), M １ and M ２ may all be alkyl groups, but from the viewpoint of electrical conductivity, it is preferable that at least one of them is a hydrogen atom, and it is more preferable that two of them are hydrogen atoms. １ｃ and M ２ｃ may all be alkyl groups, but from the viewpoint of electrical conductivity, it is preferable that at least one of them is a hydrogen atom, and it is more preferable that two of them are hydrogen atoms.

[0066] Specific examples of the structural unit of the general formula (A) include the following formulae (9), (10), (11) and (13).

[0067] In one embodiment, the structural units of the polythiophene compound used in the composition of the present invention may be composed solely of structural units of the general formula (A). In one embodiment, the polythiophene compound used in the composition of the present invention is substantially free of structural units other than structural units of the general formula (A). When the structural units of the polymer are composed solely of structural units of the general formula (A), the advantageous properties can be fully exhibited.

[0068] In another embodiment, the polythiophene compound used in the composition of the present invention may contain structural units other than the structural unit of general formula (A) above, as long as the effects of the present invention are not impaired.

[0069] However, if the content of structural units other than those of general formula (A) is too high, the advantages of the present invention will be impaired, so it is preferable that the content of structural units other than those of general formula (A) is not too high. The content of structural units other than those of general formula (A) is preferably 40 mol% or less of the total structural units in the polythiophene compound, more preferably 30 mol% or less, even more preferably 20 mol% or less, still more preferably 10 mol% or less, particularly preferably 5 mol% or less, particularly preferably 3 mol% or less, and most preferably 1 mol% or less. Furthermore, it can be 0.1 mol% or less, and it can also be 0.01 mol% or less.

[0070] A self-doping conductive polythiophene compound must have a hydrogen ion-donating phosphoric or phosphonic acid moiety. A hydrogen ion-donating phosphoric or phosphonic acid moiety refers to a phosphoric or phosphonic acid moiety having at least one —P—OH group. The number of phosphorus-containing thiophene monomer residues containing a hydrogen ion-donating phosphoric or phosphonic acid moiety in the polythiophene compound used in the composition of the present invention can be selected as desired. The proportion of phosphorus-containing thiophene monomer residues containing a hydrogen ion-donating phosphoric or phosphonic acid moiety can be selected from, for example, 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more, based on the total number of phosphorus-containing thiophene monomer residues present in the polythiophene compound (100%). Alternatively, it may be set to 100%. Furthermore, if it is desired to control the content of hydrogen ion donating groups (—P—OH) for some reason, the composition can be designed to suppress the number of hydrogen ion donating phosphoric acid or phosphonic acid moieties. In such cases, the proportion of phosphorus-containing thiophene monomer residues containing hydrogen ion donating phosphoric acid or phosphonic acid moieties can be designed to be 95% or less, 90% or less, 85% or less, 80% or less, 75% or less, or 70% or less, where the total number of phosphorus-containing thiophene monomer residues present in the polythiophene compound used in the composition of the present invention is taken as 100%.

[0071] The ratio of hydrogen ion donating phosphoric or phosphonic acid moieties to the total number of phosphoric or phosphonic acid moieties can also be designed as desired. The ratio of hydrogen ion donating phosphoric or phosphonic acid moieties can be selected from, for example, 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more, assuming that the total number of phosphoric or phosphonic acid moieties present in the polythiophene compound used in the composition of the present invention is 100%. Alternatively, it may be set to 100%. Furthermore, if it is desired to control the content of hydrogen ion donating groups for some reason, the number of hydrogen ion donating phosphoric or phosphonic acid moieties can also be designed to be suppressed. In such cases, the proportion of hydrogen ion-donating phosphoric or phosphonic acid sites can be designed to be 95% or less, 90% or less, 85% or less, 80% or less, 75% or less, or 70% or less, where the total number of phosphoric or phosphonic acid sites present in the polythiophene compound used in the composition of the present invention is taken as 100%.

[0072] The ratio of the above-mentioned hydrogen ion donating phosphoric or phosphonic acid moieties can be controlled, for example, by adjusting the type and amount of the thiophene compound used in producing the polythiophene compound.

[0073] (Molecular Weight) The molecular weight of the polythiophene compound used in the composition of the present invention is not particularly limited. The weight-average molecular weight of the polythiophene compound used in the composition of the present invention is preferably 1,000 or more, more preferably 2,000 or more. The weight-average molecular weight of the polythiophene compound used in the composition of the present invention is preferably 500,000 or less, more preferably 200,000 or less, and even more preferably 100,000 or less.

[0074] The polythiophene compound used in the composition of the present invention preferably has a phosphoric acid or phosphonic acid moiety [—OP(O)(OH) ２ or -P(O)(OH) ２], and monomer residues having a phosphoric acid or phosphonic acid monoalkyl ester structural moiety [—OP(O)(OH)(OR) or —P(O)(OH)(OR), where R is an alkyl group having 1 to 15 carbon atoms]. The phosphoric acid or phosphonic acid structural moiety and the phosphoric acid or phosphonic acid monoalkyl ester structural moiety are capable of doping the thiophene rings in the main chain of the polythiophene compound with hydrogen ions released from the hydrogen ion donating group (—P—OH).

[0075] In one embodiment of the present invention, a polythiophene compound having a specific absorbance ratio can be used. High conductivity can be achieved by a polythiophene compound having a specific absorbance ratio. Specifically, in the polythiophene compound used in the composition of the present invention, the absorbance (A) of the compound at a wavelength of 2000 nm measured using a spectrophotometer is ２０００ ) and the absorbance (A ４０７ ) from the calculation formula (A ２０００ / A ４０７ ) is 1 or more. The absorbance ratio is preferably 1.5 or more, more preferably 2 or more, even more preferably 2.5 or more, and particularly preferably 3 or more. If necessary, the absorbance ratio may be 3.5 or more, 4 or more, or even 4.5 or more. There is no particular upper limit to the absorbance ratio. However, if necessary, the upper limit of the absorbance ratio may be set to, for example, 10 or less, 8 or less, or 6 or less. The method described in Patent Document 3 can be used as a method for measuring absorbance.

[0076] [Thiophene Compound] As a monomer for producing a polythiophene compound, a known monomer compound corresponding to the structural unit of the polythiophene compound can be used.

[0077] For example, a compound represented by the following general formula (Am) can be used as a phosphorus-containing thiophene monomer compound corresponding to the structural unit (A).

[0078]

[0079] [Method for Producing Polythiophene Compound] The polythiophene compound preferably used in the composition of the present invention can be obtained by oxidatively polymerizing the above-mentioned phosphorus-containing thiophene monomer compound using an appropriate oxidizing agent, followed by an appropriate purification step. As the oxidative polymerization method, a conventionally known method for polymerizing a thiophene compound can be used.

[0080] In this specification, "oxidative polymerization" refers to a reaction in which a thiophene monomer compound or a thiophene monomer mixture is polymerized using an oxidizing agent to synthesize a polythiophene compound. Here, "oxidation" refers to the abstraction of hydrogen atoms at the 2- and 5-positions from a thiophene monomer compound during this polymerization reaction. In this specification, "oxidizing agent" refers to a reagent that triggers such an oxidation reaction. The oxidative polymerization reaction of thiophene monomers is described, for example, in Patent Document 3. Regarding the term "oxidative polymerization," the Chemical Dictionary defines it as "a process in which a compound having a hydrocarbon residue containing a double bond gradually polymerizes upon exposure to oxygen. The most prominent example is the drying of oils and fats." However, because the polymerization of thiophene monomers does not generally use oxygen in the air as an oxidizing agent, the term "oxidative polymerization" in this specification has a slightly different meaning from that used in the Chemical Dictionary.

[0081] (Monomer) A polythiophene compound containing a structural unit of the general formula (A) can be obtained by carrying out oxidative polymerization using the phosphorus-containing thiophene compound of the general formula (Am) as a polymerization monomer.

[0082] When carrying out the oxidative polymerization, the oxidative polymerization may be carried out using only one type of thiophene compound represented by the general formula (Am), or two or more types of thiophene compounds represented by the general formula (Am).

[0083] However, if the amount of monomers other than those of general formula (Am) is too large, the advantages of the present invention will be impaired, so it is preferable that the amount of monomers other than those of general formula (Am) is not too large. The amount of monomers other than those of general formula (Am) is preferably 40 mol% or less, more preferably 30 mol% or less, even more preferably 20 mol% or less, still more preferably 10 mol% or less, particularly preferably 5 mol% or less, particularly preferably 3 mol% or less, and most preferably 1 mol% or less of the total monomers used in the polymerization reaction.

[0084] (Oxidizing Agent) The oxidative polymerization reaction in the present invention is carried out in the presence of an oxidizing agent. As the oxidizing agent, an oxidizing agent generally used in the oxidative polymerization reaction of a thiophene compound can be used. Specific examples include ammonium persulfate, ferric chloride, ferric paratoluenesulfonate, ferric sulfate, and ferric nitrate.

[0085] An oxidizing agent containing an iron atom can be preferably used, more preferably ferric chloride, ferric paratoluenesulfonate, ferric sulfate, and ferric nitrate.

[0086] Two or more of the above oxidizing agents may be used in combination. When two or more oxidizing agents are used in combination, it is preferable to use an oxidizing agent containing iron atoms as one of the oxidizing agents. Specifically, a preferred combination when used in combination is a combination of ferric sulfate and ammonium persulfate.

[0087] The amount of the oxidizing agent used is not particularly limited as long as the oxidative polymerization reaction proceeds smoothly. It is preferably 1 equivalent or more, more preferably 2 equivalents or more, and particularly preferably 3 equivalents or more, relative to the monomer used in the oxidative polymerization reaction. It is also preferably 100 equivalents or less, more preferably 60 equivalents or less, and particularly preferably 20 equivalents or less.

[0088] If the amount used is within the above range, the reaction proceeds smoothly.

[0089] Since oxygen in air does not usually serve as an oxidizing agent for the polymerization of thiophene monomers, even when the polymerization reaction is carried out in the presence of air, the oxygen in air is usually not included in the amount of the oxidizing agent used in the polymerization reaction. That is, although the term "oxidative polymerization" is sometimes used to mean a polymerization reaction using oxygen present in air as an oxidizing agent, the polymerization reaction in the present invention is different from such a polymerization reaction.

[0090] (Solvent) A solvent may be used in the polymerization reaction, if necessary.

[0091] The solvent is not particularly limited as long as it is a liquid that can dissolve or disperse the reaction materials. Specific examples of the solvent include water, aqueous ammonia, aqueous solutions of hydrochloric acid, etc., alcohols such as methanol, ethanol, 1-propanol, and 2-propanol, aromatic hydrocarbons such as benzene, toluene, and xylene, ketones such as acetone and 2-butanone, halogenated hydrocarbons such as methylene chloride, chloroform, and chlorobenzene, acetonitrile, dimethylacetamide, dimethylformamide, dimethyl sulfoxide, and tetrahydrofuran. Preferred are water, aqueous ammonia, hydrochloric acid, methanol, ethanol, dimethylformamide, dimethyl sulfoxide, acetonitrile, acetone, tetrahydrofuran, and toluene, and more preferred are water, methanol, acetonitrile, dimethylformamide, and dimethyl sulfoxide.

[0092] The solvent may be used alone or in combination of two or more, preferably in the form of a mixed solvent of two or more.

[0093] (Reaction Temperature) The reaction temperature during polymerization is not particularly limited. It is preferably −20° C. or higher, more preferably −15° C. or higher, and particularly preferably −10° C. or higher. It is also preferably 80° C. or lower, more preferably 60° C. or lower, and particularly preferably 40° C. or lower.

[0094] (Reaction Time) The polymerization reaction time may be appropriately selected so long as it is sufficient for the reaction to proceed under the respective conditions. As long as the reaction proceeds sufficiently, differences in reaction time do not significantly affect the effects of the present invention.

[0095] The reaction time is preferably 1 hour or more, more preferably 3 hours or more, even more preferably 6 hours or more, even more preferably 9 hours or more, particularly preferably 12 hours or more, and can be set to 15 hours or more, 18 hours or more, 21 hours or more, or 24 hours or more as needed. Also, it is preferably 7 days or less, more preferably 5 days or less, even more preferably 3 days or less, even more preferably 2 days or less, particularly preferably 36 hours or less, and can be set to 30 hours or less, 28 hours or less, or 26 hours or less as needed.

[0096] (Hydrolysis) The polythiophene compound obtained by the polymerization reaction may be subjected to hydrolysis, if necessary. By performing hydrolysis, the ester bond of the phosphoric acid or phosphonic acid alkyl ester moiety in the polythiophene compound is decomposed to form a phosphoric acid or phosphonic acid structure moiety [—OP(O)(OH) ２ or -P(O)(OH) ２ ], a monoalkyl phosphate or phosphonate structure moiety [—OP(O)(OH)(OR) or —P(O)(OH)(OR), where R is an alkyl group having 1 to 15 carbon atoms], or a monohydrogen phosphate or phosphonate structure moiety [—OP(O)(OH)(OM ６ ) or -P(O)(OH)(OM ６ ), where M ６ is an alkali metal, alkaline earth metal, or ammonium group.

[0097] For example, hydrolysis can be carried out by a method such as treatment with a strong acid or a strong alkali. For example, hydrolysis can be carried out by a method such as heating in an acidic aqueous solution or an alkaline aqueous solution. Examples of strong acids include protonic acids such as hydrochloric acid and sulfuric acid, and Lewis acids such as trimethylsilyl bromide. Examples of strong alkalis include potassium hydroxide and sodium hydroxide. Here, when a Lewis acid is used, a method such as reacting with the Lewis acid and then reacting with water can be preferably used. Considering the stability of the polythiophene compound skeleton, treatment with an alkali is preferred.

[0098] When heating is performed during hydrolysis, the temperature is not particularly limited. It is preferably 30°C or higher, more preferably 50°C or higher. It is also preferably 100°C or lower, more preferably 90°C or lower.

[0099] The time for hydrolysis is not particularly limited, but is preferably 1 hour or more, more preferably 6 hours or more, and is preferably 4 days or less, more preferably 2 days or less.

[0100] The polythiophene compound obtained by hydrolysis may further be subjected to ion exchange as necessary to adjust the amount of hydrogen ion-donating phosphoric acid or phosphonic acid structural moieties.

[0101] (Purification) The polythiophene compound obtained by the polymerization reaction is subjected to an appropriate purification procedure. Any known method for purifying polythiophene compounds can be used as the purification procedure. For example, procedures such as centrifugation, filtration, dehydration, drying, washing, ultrafiltration, and dialysis can be performed. The number and type of purification procedures are not particularly limited. The purification procedure may be completed by performing one type of purification procedure only once, but two or more purification procedures may be performed as necessary. For example, the purification procedure may be performed three or more times, four or more times, or five or more times. Here, one type of purification procedure may be repeated two or more times, or multiple types of purification procedures may be combined to perform two or more purification procedures in total. There is no particular upper limit to the number of purification procedures, but it is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less. If the number of procedures is too large, the entire production process will require a long time, reducing production efficiency.

[0102] In a preferred embodiment, purification is performed using a chelate compound. By performing purification using a chelate compound, a resin with high conductivity can be obtained. In this specification, a chelate compound refers to a compound having multiple ligands. As a purification method using a chelate compound, any method that can bring a polythiophene compound into contact with a chelate compound can be used. A method that can bring a polythiophene compound into contact with a chelate compound in a liquid is preferred. In one embodiment, a polythiophene compound can be purified by adding a solvent and a chelate compound to the polythiophene compound and stirring the mixture. A preferred solvent is water. The temperature at which purification is performed is not particularly limited. It may be room temperature or a heated temperature. A temperature at which a mixture containing a polythiophene compound and a chelate compound can remain in a liquid state during purification is preferred.

[0103] Any conventionally known chelate compound can be used as the chelate compound. Preferably, it is a chelate compound containing a phosphorus atom and an oxygen atom. More preferably, it is a chelate compound containing a plurality (for example, two) of phosphonic acid structural moieties (-P(=O)(OH) ２) is a compound having the formula (I). For example, bisphosphonates can be used. A particularly preferred example is etidronic acid.

[0104] (Ion Exchange) The polythiophene compound obtained by the polymerization reaction may be subjected to ion exchange, if necessary, to adjust the amount of dope. The ion exchange can be carried out using an acidic aqueous solution or an ion exchange resin.

[0105] That is, when the amount of hydrogen ion donating groups of phosphoric acid or phosphonic acid, monoalkyl phosphoric acid or phosphonic acid, or monohydrogen phosphoric acid or phosphonic acid in the polythiophene compound obtained by polymerization is less than the desired amount in the entire polymer, the doping effect can be increased by ion-exchanging the metal ions or ammonium ions bonded to the phosphoric acid or phosphonic acid with hydrogen ions.

[0106] Conversely, when the amount of hydrogen ion donating groups of phosphoric acid or phosphonic acid, monoalkyl phosphoric acid or phosphonic acid, or monohydrogen phosphoric acid or phosphonic acid in the polythiophene compound obtained by polymerization is greater than the desired amount for the entire polymer, the doping effect can be reduced by ion-exchanging the hydrogen ions of the phosphoric acid or phosphonic acid, monoalkyl phosphoric acid or phosphonic acid, or monohydrogen phosphoric acid or phosphonic acid with other ions (e.g., alkali metal ions, ammonium ions, etc.).

[0107] Ion exchange can be carried out after the polymerization of the polythiophene compound. It can be carried out simultaneously with the above-mentioned purification operation, or it can be carried out before or after the purification operation. For example, when purification is carried out by filtration, if a column for filtration is filled with an ion exchange resin, ion exchange can be carried out simultaneously with purification by filtration.

[0108] As the ion exchange method, a conventionally known ion exchange method can be used.

[0109] For example, when an acidic aqueous solution is used, ion exchange can be performed by contacting the polythiophene compound product obtained by polymerization with the acidic aqueous solution. Specifically, ion exchange can be performed by, for example, stirring the polythiophene compound product in the acidic aqueous solution to react the salt portion of the phosphoric acid or phosphonic acid compound present in the polythiophene compound product with the hydrogen ions in the aqueous solution. When increasing the hydrogen ions to enhance the doping effect, it is preferable to use an excess amount of acid relative to the acidic substituents of the polythiophene compound product. The doping effect can be reduced by simply reducing the amount of acid used. In other words, the doping effect can be adjusted as desired by adjusting the amount of acid used. Furthermore, the time for reacting the polythiophene compound product with the acid can also be adjusted as desired.

[0110] For example, when using an ion exchange resin, ion exchange can be performed by contacting the polythiophene compound product with the ion exchange resin in water. To increase the hydrogen ions to enhance the doping effect, it is preferable to use a strongly acidic cation exchange resin. To decrease the hydrogen ions to reduce the doping effect, it is preferable to use a strongly basic cation exchange resin. Any method can be used to contact the polythiophene compound product with the ion exchange resin. For example, a column may be packed with the ion exchange resin and a solution containing the polythiophene compound product may be passed through it. Alternatively, the ion exchange resin may simply be placed in a container and a solution containing the polythiophene compound product may be placed in the container. Furthermore, when contacting the polythiophene compound product with the ion exchange resin, the efficiency may be improved by shaking the container or stirring the solution. The time for contacting the polythiophene compound product with the ion exchange resin can be set arbitrarily. For example, when a small amount (e.g., one drop) of polythiophene compound product solution is passed through the column, the time is set as the time from when the small amount of solution contacts the top of the ion exchange resin to when it leaves the bottom of the ion exchange resin. For example, when a large amount of polythiophene compound product solution is passed through a column, the time is set as the average of the time from when the initial part of the solution contacts the ion exchange resin at the top until it separates from the bottom of the ion exchange resin and the time from when the final part of the solution contacts the ion exchange resin at the top until it separates from the bottom of the ion exchange resin. When an ion exchange resin and a polythiophene compound product solution are placed in a container, the time is set as the time it takes for the solution and the ion exchange resin to mix in the container.

[0111] The time for performing one operation of ion exchange of the polythiophene compound product (for example, the contact time between the above-mentioned polythiophene compound product and the acidic aqueous solution or the contact time between the ion exchange resin and the polythiophene compound product) is arbitrarily set depending on the desired degree of ion exchange, but is, for example, preferably 5 seconds or more, more preferably 10 seconds or more, even more preferably 1 minute or more, and still more preferably 10 minutes or more. If the contact time is too short, the ion exchange tends to be insufficient. Also, it is preferably 1 day or less, more preferably 12 hours or less, and even more preferably 2 hours or less. If the contact time is too long, the entire production process will require a long time, and production efficiency will decrease.

[0112] The number of times the ion exchange operation is performed is not particularly limited. Ion exchange may be completed by performing only one ion exchange operation on the polythiophene compound product, or the ion exchange operation may be repeated two or more times. Repeating the ion exchange operation two or more times makes it possible to easily obtain a polythiophene compound with a high doping effect. Specifically, it is preferably repeated three or more times, more preferably repeated four or more times, and even more preferably repeated five or more times. The number of times the ion exchange operation is performed is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less. If the number of times is too large, the entire production process will require a long time, and production efficiency will decrease.

[0113] When the ion exchange operation is carried out two or more times, the same ion exchange operation may be repeated two or more times, or two or more types of ion exchange operations may be carried out.

[0114] In one preferred embodiment, the ion exchange operation can be combined with the purification operation to form a series of steps. For example, an acidic aqueous solution is added to a polythiophene compound product to perform ion exchange, and then the polythiophene compound product is purified (e.g., by centrifugation) to remove water and other components, thereby obtaining a highly purified polythiophene compound. This allows for the production of a polymer with high doping efficiency and high purity. Furthermore, this series of steps, combining the ion exchange operation with the purification operation, can be performed as a single cycle, and this cycle can be repeated multiple times. For example, an acidic aqueous solution is added to a polythiophene compound product to perform ion exchange, and then the polythiophene compound product is purified (e.g., by centrifugation) to obtain a highly purified polythiophene compound. The polythiophene compound after the first purification is then subjected to a second ion exchange by adding an acidic aqueous solution again, and then a purification step is performed again to obtain a second purified polythiophene compound with even higher purity. By repeating this series of steps, a polymer with extremely high doping efficiency and high purity can be efficiently obtained. That is, a highly purified and electrically conductive polymer can be efficiently obtained. The number of times that the cycle consisting of a series of steps including the ion exchange operation and the purification operation is repeated is not particularly limited. Specifically, it is preferably repeated three or more times, more preferably four or more times, and even more preferably five or more times. It is also preferably 20 or less times, more preferably 15 or less times, and even more preferably 10 or less times. If the number of times is too many, the entire production process will take a long time, and production efficiency will decrease.

[0115] (Amine Compound) The composition of the present invention contains a secondary amine or a tertiary amine as the amine compound. A secondary amine is a compound containing a secondary amino group. A tertiary amine is a compound containing a tertiary amino group.

[0116] The amine compound may be an aliphatic compound or an aromatic compound, but preferably is an aliphatic compound.

[0117] The amine compound may be a chain compound consisting of only a chain structure, a cyclic compound consisting of only a cyclic structure, or a compound containing both a chain structure and a cyclic structure. Preferably, the amine compound is a chain compound. The chain compound may be a linear compound or a branched compound. The amine compound may be a compound having a ring structure (heterocyclic structure) consisting of nitrogen atoms and carbon atoms. Here, the heterocyclic structure may be an aliphatic ring structure or an aromatic ring structure.

[0118] The amine compound contains a secondary or tertiary amino group and a hydrocarbon group. The amine compound may be a compound composed of a secondary or tertiary amino group and a hydrocarbon group, or may further contain other atoms or groups. Preferably, the amine compound is a compound composed of a secondary or tertiary amino group and a hydrocarbon group. In this specification, a secondary amino group refers to a group consisting of a nitrogen atom and a hydrogen atom forming a secondary amine. A tertiary amino group refers to a nitrogen atom forming a tertiary amine.

[0119] The hydrocarbon group in the amine compound may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. The aliphatic hydrocarbon group (e.g., an alkyl group) present in the amine compound may be a chain hydrocarbon group (e.g., a chain alkyl group) or a cyclic hydrocarbon group (e.g., a cyclic alkyl group). Preferably, the aliphatic hydrocarbon group (e.g., an alkyl group) is a chain aliphatic hydrocarbon group (e.g., a chain alkyl group). The chain aliphatic hydrocarbon group (e.g., a chain alkyl group) may be a linear aliphatic hydrocarbon group (e.g., a linear alkyl group) or a branched aliphatic hydrocarbon group (e.g., a branched alkyl group). More preferably, the aliphatic hydrocarbon group (e.g., an alkyl group) is a linear aliphatic hydrocarbon group (e.g., a linear alkyl group).

[0120] The hydrocarbon group contained in the amine compound may be a monovalent hydrocarbon group, a divalent hydrocarbon group, a trivalent hydrocarbon group, or a tetravalent hydrocarbon group. The hydrocarbon group contained in the amine compound is preferably a monovalent hydrocarbon group. When the amine compound contains a divalent hydrocarbon group (e.g., an alkylene group), the hydrocarbon group is preferably bonded to two nitrogen atoms. When the amine compound contains a trivalent hydrocarbon group, the hydrocarbon group is preferably bonded to three nitrogen atoms. When the amine compound contains a tetravalent hydrocarbon group, the hydrocarbon group is preferably bonded to four nitrogen atoms.

[0121] In this specification, the term "alkyl group" refers to a monovalent group generated by removing one hydrogen atom from a chain or cyclic saturated aliphatic hydrocarbon (alkane). In the case of a chain, it is generally C ｋ H ２ｋ＋１ - (where k is a positive integer). A chain alkyl may be a straight chain or a branched chain. A cyclic alkyl may be composed of only a cyclic structure, or may have a structure in which a chain alkyl is further bonded to a cyclic structure. In this specification, the term "alkylene group" refers to a divalent group generated by losing one more hydrogen atom from an alkyl group.

[0122] (Number of Amino Groups in Amine Compound) The amine compound preferably has one secondary or tertiary amino group, but may contain multiple amino groups. For example, the amine compound may have a structure in which two amino groups are linked by a divalent hydrocarbon group (e.g., an alkylene group).

[0123] The amine compound may be a compound having both a secondary amino group and a tertiary amino group. Alternatively, the amine compound may be a compound having a primary amino group in addition to a secondary or tertiary amino group. For convenience, herein, amine compounds having a primary amino group and a secondary amino group are classified as secondary amines, amine compounds having a primary amino group and a tertiary amino group are classified as tertiary amines, and amine compounds having a primary amino group, a secondary amino group, and a tertiary amino group are classified as tertiary amines. Preferably, the amine compound is a compound having no primary amino groups. More preferably, the amine compound is a compound having no amino groups other than a secondary amino group or a compound having no amino groups other than a tertiary amino group. Particularly preferably, the amine compound is a compound having no amino groups other than one secondary amino group or a compound having no amino groups other than one tertiary amino group.

[0124] The amine compound is preferably a compound that does not have any nitrogen-containing groups other than a secondary amino group and a tertiary amino group.

[0125] (Atoms Constituting Amine Compound) The amine compound preferably comprises a nitrogen atom, a carbon atom, and a hydrogen atom. If necessary, the amine compound may further contain other atoms (for example, an oxygen atom).

[0126] The number of nitrogen atoms in the amine compound is preferably 5 or less, more preferably 3 or less, even more preferably 2 or less, and particularly preferably 1.

[0127] The total number of carbon atoms in the amine compound is 9 or less, and in one embodiment, 8 or less. The total number of carbon atoms is 4 or more, preferably 5 or more, and more preferably 6 or more. In one embodiment, it is 7 or more. In a particularly preferred embodiment, the total number of carbon atoms is 8 or 9.

[0128] The number of carbon atoms in the alkyl groups in the amine compound is 1 to 8. Among the alkyl groups in the amine compound, the alkyl group having the most carbon atoms has 4 or more carbon atoms, preferably 4 to 7 carbon atoms, and more preferably 4 to 6 carbon atoms.

[0129] (Secondary amine) A secondary amine is a compound having a secondary amino group. In one embodiment, the secondary amine has no amino groups other than the secondary amino group. Preferably, the secondary amine has no nitrogen-containing groups other than the secondary amino group.

[0130] The number of secondary amino groups in the secondary amine compound is 5 or less, preferably 3 or less, more preferably 2 or less, and particularly preferably 1.

[0131] The secondary amine is preferably a dialkylamine. That is, the secondary amine is preferably composed of a secondary amino group and an alkyl group. If necessary, the secondary amine may further contain other groups (e.g., an alkylene group, a hydroxyl group, etc.).

[0132] Preferably, the secondary amine is a linear compound, more preferably a linear dialkylamine consisting of two linear alkyl groups and one NH group.

[0133] The combination of two alkyl groups in the dialkylamine is not particularly limited as long as it satisfies the above-mentioned characteristics of the carbon number of the amine compound. Examples of the combination of two alkyl groups in the dialkylamine include a combination of an alkyl group having 4 carbon atoms and an alkyl group having 1, 2, 3, or 4 carbon atoms, a combination of an alkyl group having 5 carbon atoms and an alkyl group having 1, 2, 3, or 4 carbon atoms, a combination of an alkyl group having 6 carbon atoms and an alkyl group having 1, 2, or 3 carbon atoms, a combination of an alkyl group having 7 carbon atoms and an alkyl group having 1 or 2 carbon atoms, and a combination of an alkyl group having 8 carbon atoms and an alkyl group having 1 carbon atom.

[0134] A specific example of a preferred secondary amine is di-n-butylamine.

[0135] (Tertiary amine) A tertiary amine is a compound having a tertiary amino group. In one embodiment, the tertiary amine has no amino groups other than the tertiary amino group. Preferably, the tertiary amine has no nitrogen-containing groups other than the tertiary amino group.

[0136] The number of tertiary amino groups in the tertiary amine compound is 3 or less, preferably 2 or less, and more preferably 1. When the tertiary amine has both a secondary amino group and a tertiary amino group, the number of secondary amino groups is 4 or less, preferably 2 or less, and more preferably 1, and the number of tertiary amino groups is 2 or less, and preferably 1.

[0137] The tertiary amine is preferably a trialkylamine. That is, the tertiary amine is preferably composed of a tertiary amino group and an alkyl group. If necessary, the tertiary amine may further contain other groups (e.g., an alkylene group, a hydroxyl group, etc.).

[0138] The alkyl group in the trialkylamine is preferably a straight-chain alkyl group.

[0139] The combination of three alkyl groups in the trialkylamine is not particularly limited as long as it satisfies the characteristics of the carbon number of the amine compound described above. Specific examples of the combination of three alkyl groups in the trialkylamine include a combination of a C4 alkyl group, a C1 alkyl group, and a C1 alkyl group, a combination of a C4 alkyl group, a C2 alkyl group, and a C1 or C2 alkyl group, a combination of a C4 alkyl group, a C3 alkyl group, and a C1 or C2 alkyl group, a combination of a C4 alkyl group, a C4 alkyl group, and a C1 alkyl group, a combination of a C5 alkyl group, a C1 alkyl group, and a C1 alkyl group, a combination of a C5 alkyl group, a C2 alkyl group, and a C1 or C2 alkyl group, a combination of a C5 alkyl group, a C3 alkyl group, and a C1 alkyl group, a combination of a C6 alkyl group, a C1 or C2 alkyl group, and a C1 alkyl group, and a combination of a C7 alkyl group, a C1 alkyl group, and a C1 alkyl group.

[0140] Specific examples of preferred tertiary amines include N,N-dimethylhexylamine and N-methyldibutylamine.

[0141] (Amount of amine compound) The content of the amine compound in the composition of the present invention is not particularly limited, but is preferably determined based on the amount of phosphonic acid groups of the polymer compound. The amount of the amine compound is preferably 0.1 mol or more, more preferably 0.2 mol or more, even more preferably 0.3 mol or more, and particularly preferably 0.5 mol or more, relative to 1 mol of phosphonic acid groups of the polymer compound. If necessary, it can be 0.7 mol or more or 1 mol or more. The amount of the amine compound is preferably 20 mol or less, more preferably 10 mol or less, even more preferably 7 mol or less, and particularly preferably 5 mol or less, relative to 1 mol of phosphonic acid groups of the polymer compound. If necessary, it can be 4 mol or less or 3 mol or less.

[0142] The composition of the present invention may contain one type of amine compound, or may contain two or more types of amine compounds. The composition of the present invention may contain two or more types of secondary amines, may contain two or more types of tertiary amines, or may contain one or more types of secondary amines and one or more types of tertiary amines. When the composition contains two or more types of the secondary amines or tertiary amines, it is preferable that the total amount thereof is within the above-mentioned range.

[0143] (Other Components) The composition of the present invention is preferably composed of the above-mentioned components. The composition of the present invention may contain components other than the above-mentioned components, as necessary. In one embodiment, the composition of the present invention does not contain any nitrogen-containing compounds other than amine compounds. In one embodiment, the composition of the present invention does not contain any nitrogen-containing compounds other than secondary amines or tertiary amines. In one embodiment, the composition of the present invention does not contain ammonia.

[0144] (Additives other than amine compounds) The composition of the present invention may contain additives other than amine compounds, as long as the effects of the invention are not impaired. Examples of other additives include additives commonly used in this technical field, such as basic compounds such as ammonia or metal hydroxides, dopants such as polystyrene sulfonic acid, and surfactants.

[0145] (Preparation of Composition) The composition of the present invention can be prepared by mixing its components by a known method. For example, it can be prepared by mixing a conductive polymer compound (e.g., a polythiophene compound) with an amine compound. The order of mixing is not particularly limited.

[0146] (Antistatic Agent) The antistatic agent of the present invention is a solution or dispersion of the composition in a solvent, the composition itself, or a solid containing the composition. From the viewpoint of ease of handling, the solution or dispersion of the composition in a solvent is preferred, and a solution in which the composition is dissolved in a solvent is more preferred.

[0147] (Solvent) The solvent used in the antistatic agent of the present invention may be an inorganic solvent or an organic solvent. A solvent capable of dissolving an amine compound is preferred. In one preferred embodiment, the solvent is water. Furthermore, when a compound that is a gas at room temperature is used as the amine compound, dissolving the compound in a solvent (e.g., water) to form an amine compound solution (e.g., an amine compound aqueous solution) facilitates the mixing operation with the polythiophene compound. When a compound that is a liquid at room temperature is used as the amine compound, ammonia may be dissolved in the amine compound before use. When a compound that is a gas at room temperature is used as the amine compound, it is preferred to use the amine compound dissolved in a solvent (e.g., water).

[0148] (Preparation of Antistatic Agent) The antistatic agent of the present invention can be prepared by dissolving or dispersing the composition or its components in a solvent by a known method, or by mixing the composition and other components by a known method.

[0149] (pH of Antistatic Agent) When the antistatic agent is used in the form of an aqueous solution using water as the solvent for the antistatic agent, the pH of the aqueous solution of the antistatic agent is preferably 7 or higher, more preferably 8 or higher, and even more preferably 9 or higher. The pH is preferably 12 or lower, more preferably 11.5 or lower, and even more preferably 11 or lower. If the pH is too high or too low, it may be difficult to obtain the desired shape during molding.

[0150] (Method for producing an article having antistatic properties) In one embodiment, the antistatic agent of the present invention can be used in a method for producing an article having antistatic properties. The method includes a step of applying the antistatic agent to a substrate to form an antistatic film.

[0151] (Film Forming Process) In one embodiment, the antistatic agent of the present invention is used in a process for forming an antistatic film. Any known film-forming method can be used for forming an antistatic film. Since conductive polymer compounds obtained by polymerization usually cannot be used as antistatic films in their original form, a method of processing them into a film of a desired thickness by molding is known. The antistatic agent of the present invention can be used in such a known molding method. In this specification, the process of processing a conductive polymer compound obtained by polymerization into a desired shape is referred to as a molding process. Furthermore, when the desired shape is a film, the process of processing a conductive polymer compound obtained by polymerization into a film shape is referred to as a film-forming process. For example, a film can be formed by applying the antistatic agent of the present invention to a smooth substrate surface and drying it.

[0152] (Article with Antistatic Properties) In one aspect, the present invention relates to an article having an antistatic film obtained from the above-mentioned antistatic agent. The article having this antistatic film has high antistatic properties.

[0153] The antistatic agent of the present invention can be a solid composition containing no solvent. Such a solid composition can be formed into a film shape and used as an antistatic film.

[0154] The antistatic agent of the present invention can also be a liquid composition containing a solvent (e.g., water). Such a liquid composition can be used as a material for producing an antistatic film. For example, the antistatic agent of the present invention in the form of an aqueous solution containing water as a solvent can be used as a material for forming an antistatic film on an article (e.g., a resist substrate).

[0155] (Uses) The antistatic agent of the present invention can be used to form an antistatic film on the surface of various known articles that require antistatic properties.

[0156] In one preferred embodiment, the antistatic agent of the present invention can be used to form an antistatic film on the resist surface of a substrate having a resist. That is, the antistatic agent of the present invention can be suitably used to impart antistatic properties to the resist of an article in which a resist is laminated on a substrate. The antistatic film produced using the antistatic agent of the present invention has high antistatic properties, and therefore can prevent deviation due to charge-up during a drawing process using an electron beam, allowing for the formation of a pattern with higher precision.

[0157] The substrate may be any known substrate used for a resist substrate, such as a compound semiconductor wafer such as a silicon wafer, a gallium arsenide wafer, or an indium phosphide wafer, a quartz substrate, or a magnetic substrate.

[0158] Any known resist can be used as the resist. The resist may be a positive resist or a negative resist. The composition of the present invention is more preferably used for a positive resist.

[0159] Furthermore, the resist may be either a non-chemically amplified resist or a chemically amplified resist. That is, the antistatic agent of the present invention can be used for both a non-chemically amplified resist and a chemically amplified resist. As the non-chemically amplified resist, any known non-chemically amplified resist can be used. As the chemically amplified resist, any known chemically amplified resist can be used.

[0160] Chemically amplified resists containing photoacid generators for acid-catalyzed reactions and non-chemically amplified resists containing compounds with functional groups that absorb and react with light have different surface properties due to the difference in material composition. However, the antistatic agent of the present invention can achieve both film-forming properties on the surface of chemically amplified resists and non-chemically amplified resists.

[0161] The antistatic agent of the present invention can be applied to the resist surface by any known method. Preferably, the antistatic agent can be applied by spin coating using a spin coater. Alternatively, various known coating methods can be used, such as immersing a resist substrate in the antistatic agent, spraying the antistatic agent onto a resist substrate, inkjet printing, screen printing, and coating using a bar coater.

[0162] The present invention will be described below with reference to examples, but the present invention is not limited to these examples in any way.

[0163] Examples 1 to 3 and Comparative Examples 1 to 10 (Preparation of Conductive Polymer Compound) A polythiophene compound identical to polythiophene compound 1 in International Publication WO2022 / 260007 was synthesized by the method described in Example 5 of the publication.

[0164] (Amine Compound) The following amine compounds were used. (1) Di-n-butylamine (Kishida Chemical Co., Ltd., secondary amine, maximum number of carbon atoms in the alkyl group is 4, total number of carbon atoms is 8) (2) N,N-dimethylhexylamine (Sigma-Aldrich Co., Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 6, total number of carbon atoms is 8) (3) N-methyldibutylamine (Sigma-Aldrich Co., Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 4, total number of carbon atoms is 9) (4) Trimethylamine (Kishida Chemical Co., Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 1, total number of carbon atoms is 3) (5) Triethylamine (Fujifilm Wako Pure Chemical Industries, Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 2, total number of carbon atoms is 6) (6) Tripropylamine (Fujifilm Wako Pure Chemical Industries, Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 3, total number of carbon atoms is 9) (7) N,N-Diisopropylethylamine (Kishida Chemical Co., Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 3, total number of carbon atoms is 8) (8) Diisopropylamine (Tokyo Chemical Industry Co., Ltd., secondary amine, maximum number of carbon atoms in the alkyl group is 3, total number of carbon atoms is 6) (9) n-Hexylamine (Tokyo Chemical Industry Co., Ltd., primary amine, maximum number of carbon atoms in the alkyl group is 6, total number of carbon atoms is 6) (10) n-Octylamine (Tokyo Chemical Industry Co., Ltd., primary amine, maximum number of carbon atoms in the alkyl group is 8, total number of carbon atoms is 8) (11) N,N-Dimethyloctylamine (Tokyo Chemical Industry Co., Ltd., tertiary amine, maximum number of carbon atoms in the alkyl group is 8, total number of carbon atoms is 10).

[0165] (Preparation of Antistatic Agent) An amine compound was mixed with water to prepare an aqueous solution containing the amine compound. This aqueous solution containing the amine compound was added to a mixture of 100 to 200 mg of a conductive polymer and water to prepare a total of 10 ml of an aqueous solution (antistatic agent) having a pH of 10 to 11.

[0166] The following table shows the amine compounds and the amounts thereof used in each of Preparation Examples 1 to 11. The table also shows whether or not an aqueous solution could be prepared.

[0167] *1: The number of carbon atoms in the alkyl group with the most carbon atoms

[0168] The equivalent weight of the amine compound in the table is the equivalent weight relative to the number of moles of phosphonic acid groups in the conductive polymer compound. Since the phosphonic acid group has two OH groups, the 2 to 3 equivalents shown in the table are 1 to 1.5 equivalents based on the number of moles of OH groups in the phosphonic acid group.

[0169] Aqueous solutions were formed for the compositions of Preparation Examples 1 to 8, but not for the compositions of Preparation Examples 9 to 11. That is, even when 3 equivalents of the amine compound were added, the solution separated into an organic phase and an aqueous phase, and the amine compound did not dissolve in water. Similarly, even when the amount of the amine compound added was changed to 2 equivalents, the amine compound also did not dissolve in water.

[0170] (Materials for preparing samples for evaluating antistatic agents) The following materials were used. (1) Substrate: (1A) Silicon wafer (manufactured by Mitsubishi Materials Trading Co., Ltd., N-type <1,0,0>, 525 μm thick, 2 Ωcm) (1B) Polished square synthetic quartz plate (20 × 20 × 1 mm) (As One, 3-2393-02) (2) Resist: (2A) UVIII (manufactured by Rohm and Haas Electronics Materials, chemically amplified positive-tone DUV (Deep Ultraviolet) resist) (2B) ZEP520A (manufactured by Nippon Zeon Co., Ltd., non-chemically amplified positive-tone electron beam resist) (3) Antistatic agent: (3A) Antistatic agent prepared in Preparation Examples 1 to 8 above (3B) Antistatic agent 9: Esspacer 300AX-01 (manufactured by Resonac Corporation, a polyisothianaphthene-containing antistatic agent having a sulfonic acid moiety (commercially available product)) (3C) Antistatic agent 10: Esspacer 300Z (manufactured by Resonac Corporation, a polyisothianaphthene-containing antistatic agent having a sulfonic acid moiety (commercially available product)).

[0171] (Preparation of Resist Substrates for Evaluation) (Chemically Amplified Resist Substrates) A ​​polished synthetic quartz square plate and a silicon wafer cut into 1 cm squares were each placed in a spin coater (Mikasa Co., Ltd. MS-A150), and UVIII (chemically amplified), a resist film material, was applied to the surface. The substrates were then spin-coated at 500 rpm for 5 seconds and 3000 rpm for 45 seconds. The spin-coated substrates were annealed at 120°C for 1 minute to form resist films with thicknesses of 100 to 300 nm on the substrates. The laminates obtained using the polished synthetic quartz square plate and the laminates obtained using the silicon wafer substrate were each used as chemically amplified resist substrates.

[0172] (Non-chemically amplified resist substrate) A polished synthetic quartz square plate and a silicon wafer cut into 1 cm squares were each placed in a spin coater (Mikasa Co., Ltd., MS-A150), and the surface was coated with ZEP (non-chemically amplified), a resist film material. The surface was then spin-coated at 500 rpm for 5 seconds and 3000 rpm for 45 seconds. The spin-coated silicon wafer was annealed at 170°C for 3 minutes to form a resist film with a thickness of 100 to 300 nm on the silicon wafer. The laminate obtained using the polished synthetic quartz square plate and the laminate obtained using the silicon wafer substrate were each used as a non-chemically amplified resist substrate.

[0173] (Evaluation of film-forming properties of antistatic agents) A coating process was carried out by spin-coating each antistatic agent onto a resist substrate for evaluation prepared using the silicon wafer. The resist substrate was set on a spin coater (MS-A150, Mikasa Co., Ltd.), and the antistatic agent was applied to its surface. The substrate was then spun at 500 rpm for 5 seconds and at 1000 rpm for 45 seconds. Film formation was judged visually. By comparing the samples before and after the coating process, it was determined that a film had been formed if the color originating from the antistatic agent composition could be confirmed.

[0174] When the antistatic agents of Preparation Examples 1 to 3 were used (Examples 1 to 3), the antistatic agent composition was laminated over the entire surface of the resist substrate after the coating process, both in the case where a chemically amplified resist substrate was used and in the case where a non-chemically amplified resist substrate was used.

[0175] When the antistatic agents of Preparation Examples 4 to 8 were used (Comparative Examples 1 to 5), and a non-chemically amplified resist substrate was used, the antistatic agent composition completely flowed out from the resist substrate when spun in a spin coater, and therefore, no antistatic agent composition remained on the resist substrate after the coating process.

[0176] In the case where antistatic agent 9 was used (Comparative Example 9), when a chemically amplified resist substrate was used, the antistatic agent composition was coated on the substrate after the coating process. However, in Comparative Example 9, when a non-chemically amplified resist substrate was used, all of the antistatic agent composition flowed out from the resist substrate when spun in the spin coater. Therefore, no antistatic agent composition was present on the resist substrate after the coating process.

[0177] In the case where antistatic agent 10 was used (Comparative Example 10), when a non-chemically amplified resist substrate was used, the antistatic agent composition was laminated over the entire surface of the resist substrate after the coating process. However, when a chemically amplified resist substrate was used in Comparative Example 10, the antistatic agent composition completely flowed out from the resist substrate when spun in a spin coater. Therefore, no antistatic agent composition was present on the resist substrate after the coating process.

[0178] The evaluation results of the film-forming properties are shown in the table below.

[0179] -: Film-forming property evaluation test was not performed.

[0180] Thus, the compositions of Examples 1 to 3 could be formed into films on both UVIII (chemically amplified resist) and ZEP (non-chemically amplified resist) resist substrates. The compositions of Comparative Examples 1 to 5 and 9 could not be formed into films on ZEP resist substrates. The composition of Comparative Example 10 could not be formed into films on UVIII resist substrates.

[0181] (Evaluation of Antistatic Effect) On a resist substrate prepared using a polished synthetic quartz square plate, the same coating process as in the coating process in the film-forming property evaluation was carried out using the antistatic agent that was able to form a film in the film-forming property evaluation. As a result, a laminate was obtained in which the antistatic agent composition was laminated over the entire surface of the resist substrate. The antistatic effect of the obtained laminate was evaluated at current values ​​of 1 nA and 50 nA as follows.

[0182] Using an electron beam lithography system (ELS-S50LBC, manufactured by Elionix Co., Ltd., using a 50 kV electron beam), an electron beam was irradiated at various current values ​​onto a resist substrate laminated with an antistatic film. As shown in FIG. 1, parallel lines 500 microns in length were drawn at 2.5 micron intervals. Note that although FIG. 1 shows lines only near the right edge of the square, lines were drawn at equal intervals over the entire square. In other words, a total of 201 lines were drawn to create a square with four sides of 500 microns each. The resist substrate was then rinsed with water.

[0183] Thereafter, a development step was carried out. Here, for the UVIII resist substrate, the resist substrate after writing was immersed in a developer (NMD-3 2.38% manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 30 seconds and rinsed with water. For the ZEP resist substrate, the resist substrate after writing was immersed in a developer (ZED-N50 manufactured by Zeon Corporation) for 30 seconds and rinsed with isopropyl alcohol.

[0184] The patterned resist substrate was then dried by heating on a hot plate at 130° C. for 90 seconds to remove water.

[0185] The resist substrate thus obtained, which had been patterned with a square resist pattern, was observed under an optical microscope and photographed.

[0186] As a result, when the 201 straight lines and the squares were drawn without distortion, as in the optical microscope photograph of Figure 2A, the antistatic effect was evaluated as good, whereas when the straight lines and the squares were distorted, as in the optical microscope photograph of Figure 2B, the antistatic effect was evaluated as poor.

[0187] Specifically, in Examples 1 to 3, when writing on a UVIII resist substrate at a current value of 1 nA and when writing on a ZEP resist substrate at a current value of 50 nA, no distortion of the lines or squares was observed. That is, the distortion was approximately 0 microns. When observing an optical microscope photograph of a 500-micron square, a change in the length of a side by 1% or more (5 microns or more) is recognized as a distortion of the square, so the distortion of the square in the above observation results was less than 5 microns (i.e., less than 1% of the desired length). Furthermore, no damage (cracks, etc.) to the resist film was observed.

[0188] In Comparative Example 9, when a resist substrate having UVIII was written at a current value of 1 nA, no distortion of the lines and squares was observed. That is, the distortion was 0 microns. However, when a resist substrate was written at a current value of 50 nA, distortion of the lines and squares was observed. Of the four sides of the square, the side with the greatest distortion was approximately 600 microns, resulting in a distortion of approximately 100 microns (i.e., approximately 20% of the desired length).

[0189] From these results, it was confirmed that the antistatic agent of Comparative Example 9 was able to form an antistatic film on a UVIII resist substrate, and that a sufficient antistatic effect was obtained when the electron beam current value during patterning was low, but that a sufficient antistatic effect was not obtained when the electron beam current value was high.

[0190] In Comparative Example 10, when writing was performed on a ZEP resist substrate at a current value of 1 nA and a current value of 50 nA, no distortion of the lines and squares was observed. That is, the distortion was 0 microns. However, when writing was performed at a current value of 50 nA, distortion of the lines and squares was observed. Of the four sides of the square, the side with the greatest distortion was approximately 600 microns, resulting in a distortion of approximately 100 microns (i.e., approximately 20% of the desired length).

[0191] From these results, it was confirmed that the antistatic agent of Comparative Example 10 was able to form an antistatic film on a ZEP resist substrate, and provided a sufficient antistatic effect when the electron beam current value during patterning was low, but did not provide a sufficient antistatic effect when the electron beam current value was high.

[0192] (Discussion) In Examples 1 to 3, the aqueous solution (antistatic agent) for coating on the resist was easy to prepare, film-forming properties on both chemically amplified and non-chemically amplified resists were good, and antistatic effects were achieved even at high electron beam current values.

[0193] In Comparative Examples 9 and 10, which used conventional antistatic agents, an antistatic effect was confirmed when the electron beam current was 1 nA, but the antistatic effect was insufficient when the current was 50 nA. However, in Examples 1 to 3, it was confirmed that a sufficiently good antistatic effect was exhibited even at a current value of 50 nA. Therefore, the antistatic agent of the present invention is significantly more advantageous than conventional techniques in forming finer circuits and shortening process times.

[0194] Furthermore, it was confirmed that Comparative Example 9 exhibited poor film-forming properties on the surface of a non-chemically amplified resist, and Comparative Example 10 exhibited poor film-forming properties on the surface of a chemically amplified resist. However, it was confirmed that Examples 1 to 3 exhibited good film-forming properties on the surfaces of both chemically amplified and non-chemically amplified resists. In this respect, too, the antistatic agent of the present invention is advantageous over the prior art.

[0195] According to the present invention, an antistatic agent for producing an antistatic film having excellent antistatic properties is provided. An article having an antistatic film produced using the antistatic agent of the present invention can be used as a component for various products. The antistatic agent of the present invention is particularly useful for forming an antistatic film for a resist.

[0196] As described above, the present invention has been illustrated using preferred embodiments of the present invention, but the present invention should not be construed as being limited to these embodiments. It is understood that the scope of the present invention should be interpreted only by the claims. It is understood that a person skilled in the art can implement an equivalent scope based on the description of the present invention and common general knowledge from the description of specific preferred embodiments of the present invention. It is understood that the contents of the patents, patent applications, and literature cited in this specification should be incorporated by reference into this specification as if the contents themselves were specifically set forth in this specification.

Claims

1. An antistatic composition comprising a conductive polymer compound having a phosphonic acid moiety and / or a phosphoric acid moiety and an amine compound, wherein the amine compound is a secondary amine or a tertiary amine, has one or two alkyl groups having 4 or more carbon atoms, and has a total of 5 to 9 carbon atoms.

2. An antistatic agent used as a material in a method for forming an antistatic film on the surface of an article, wherein the antistatic agent is an aqueous solution and comprises the antistatic agent composition of claim 1.

3. The antistatic agent according to claim 2, wherein the article is a circuit board having a resist as a surface layer.

4. An antistatic agent for forming an antistatic film on the surface of an article, wherein the antistatic agent is a solid and comprises the antistatic agent composition of claim 1.

5. The antistatic composition according to claim 1, wherein the amine compound does not have a primary amino group.

6. The antistatic composition according to claim 1, wherein the amine compound is an aliphatic amine compound.

7. The antistatic composition according to claim 1, wherein the amine compound has one amino group, which is a secondary amino group or a tertiary amino group, and the alkyl group is a chain alkyl group.

8. The antistatic composition according to claim 1, wherein the total number of carbon atoms in the amine compound is 8 or 9.

9. The antistatic composition according to claim 1, wherein the alkyl group is a chain alkyl group having 4 to 6 carbon atoms.

10. The amine compound contains two butyl groups, or the amine compound contains one C ５ ~C ８ The antistatic composition according to claim 1 , which comprises an alkyl group.

11. The antistatic composition according to claim 1, wherein the amine compound is selected from di-n-butylamine, N,N-dimethylhexylamine, and N-methyldibutylamine.

12. The antistatic composition according to claim 1, wherein the conductive polymer compound is a polythiophene compound having a structure in which a 1,4-dioxane ring is condensed with a thiophene ring, and wherein the substituent having the phosphonic acid moiety and / or phosphoric acid moiety is bonded to the 1,4-dioxane ring.

13. The conductive polymer compound is represented by the following formula (13): The antistatic composition according to claim 1, comprising a repeating unit represented by the following formula:

14. An antistatic film comprising the antistatic agent according to claim 4.

15. An article having a substrate and a coating present on a surface of the substrate, the coating being the antistatic film of claim 14.

16. A method for producing an article having antistatic properties, comprising the step of applying the antistatic agent according to claim 2 or 3 onto a substrate to form an antistatic film.

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