JP2017502337A - Conductive composition for forming back electrode of liquid crystal display device - Google Patents

Abstract

The present invention relates to a conductive composition for forming a back electrode of a liquid crystal display device. Specifically, the present invention includes a conductive polymer and a specific thermal acid generator in the composition obtained by the sol-gel reaction of the silane coupling agent, and the dispersion degree of the conductive polymer in the composition is increased. It is possible to provide an antistatic back electrode that is optimized and has excellent transmittance and surface hardness in a liquid crystal display device and improved coating film reliability. In particular, according to the present invention, reliability can be ensured so that there is little change in surface resistance over time after coating with increased hardness and coating.

Description

  The present invention relates to a conductive composition used for forming a back electrode of a liquid crystal display device with excellent coating film reliability.

In the electrode forming technique, the back electrode particularly in the liquid crystal display device plays a role of blocking static electricity applied from the outside.
In the case of ITO (Indium-tin-oxide) or IZO (Indium-Zinc-oxide) used as a back electrode (Korean Registered Patent No. 0603826) in a conventional liquid crystal display, a vacuum deposition process is required, and resistance in its characteristics The surface hardness is excellent, but the permeability is not excellent.
In recent years, due to the crisis of depletion of indium resources, interest in development of various transparent electrode materials for replacing ITO has increased. However, in the case of many transparent electrode materials that have been developed to date, such as conductive polymers or inorganic conductive compositions such as metals and metal oxides, the actual transmittance shows unsatisfactory results. is there.
Among them, in the case of a coating film using a conductive polymer, the permeability is excellent, but there is a problem of a decrease in reliability due to an increase in surface resistance due to a period for use as an electrode forming material.

Korean Registered Patent No. 10-0603826 Republic of Korea Registered Patent No. 10-059329

In order to solve the problems of the prior art as described above, the present invention provides a liquid crystal display capable of improving the reliability in a film state particularly in the formation of a back electrode of a liquid crystal display device in forming an electrode. It is an object to provide a conductive composition for forming a back electrode of a device and a back electrode of a liquid crystal display device using the same.
It is another object of the present invention to provide a method capable of minimizing an increase in sheet resistance according to elapse of time after forming a coating film and improving coating properties and hardness.

The present invention comprises 5 to 40 parts by weight of a silane coupling agent,
50 to 90 parts by weight of solvent,
0.1 to 10.0 parts by weight of dilute hydrochloric acid or acetic acid solution,
5 to 40 parts by weight of a conductive polymer solution having a solid content of 0.1 to 5.0 wt%; and 0.001 to 1.0 parts by weight of an acid generator;
A conductive composition for forming a back electrode of a liquid crystal display device is provided.

  The acid generator may be an amine blocked, a covalent blocked, a metal blocked, and a quaternary ammonium blocked thermal acid generator. One or more selected from the group consisting of:

  The generator may be one or more selected from the group consisting of dodecylbenzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, and derivatives thereof.

  The solvent is selected from the group consisting of i) water, ii) alcohol compounds, and iii) propylene glycol monoethyl ether, dimethylformamide, acetylacetone, 1-methyl-2-pyrrolidinone, dipropyl ketone and ethyl lactate 1 It is preferable to include a solvent of more than one species.

  The conductive polymer solution may have a solid content of the conductive polymer of 0.1 to 5% by weight and may include 95 to 99.9% by weight of a solvent.

  The conductive polymer may include one or more selected from the group consisting of polyaniline, polypyrrole, polythiophene, and derivatives thereof, and preferably includes poly (3,4-ethylenedioxythiophene).

  The conductive polymer is dodecylbenzenesulfonic acid, toluenesulfonic acid, camphorsulfonic acid, benzenesulfonic acid, hydrochloric acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, their salt compounds, 2-sulfosuccine. Selected from the group consisting of acid ester salts, sodium 5-sulfoisophthalate, dimethyl-5-sodium sulfoisophthalate, 5-sodiumsulfo-bis (β-hydroxyethyl) isophthalate and poly (4-styrenesulfonate) It is preferable to further include one or more dopants. The conductive polymer preferably further includes poly (4-styrenesulfonate) as a dopant.

  As the conductive polymer, poly (3,4-ethylenedioxythiophene): poly (4-styrenesulfonate) (PEDOT: PSS) is preferably used.

  The silane coupling agent is selected from the group consisting of alkyloxysilanes having 1 to 20 carbon atoms, aminosilanes, vinylsilanes, epoxysilanes, methacryloxysilanes, isocyanate silanes, and fluorine silanes. 1 or more types may be sufficient.

In addition, according to the present invention, 0.1 to 1.0 part by weight of a surfactant may be further included with respect to 100 parts by weight of the entire composition.
Further, 0.1 to 30 parts by weight of one or more binder resins selected from the group consisting of polyacrylic resins, polyurethane resins, epoxy resins and polyester resins are added to 100 parts by weight of the conductive composition. Further can be included.

  The present invention also provides a back electrode for a liquid crystal display device formed by applying the conductive composition described above.

  In the present invention, the use of a specific thermal acid generator (TAG) in the conductive composition for the back electrode enables additional acid generation during baking after coating. It is possible to form a coating film having a degree of cross-linking between silane coupling agents that are more rigid by additionally proceeding hydrolysis of a silane compound (eg, TEOS). Moreover, this invention can optimize the dispersity of a conductive polymer within the electroconductive composition for back electrodes. Accordingly, the present invention can improve the surface resistance with the passage of time after the coating film is formed in a liquid crystal display device (LCD), in particular, a horizontal electric field type liquid crystal display device such as IPS or FFS, that is, improve reliability. it can.

Hereinafter, the present invention will be described in detail.
According to a preferred embodiment of the invention, 5 to 40 parts by weight of silane coupling agent, 50 to 90 parts by weight of solvent, 0.1 to 10.0 parts by weight of dilute hydrochloric acid or acetic acid, 0.1 to 5.0 wt% solids There is provided a conductive composition for forming a back electrode of a liquid crystal display device, comprising 5 to 40 parts by weight of a conductive polymer solution having an acid generator; and 0.001 to 1.0 part by weight of an acid generator.

  The present invention has an advantage that the reliability of the back electrode coating film can be improved by using TAG (Thermal Acid Generator) which is an acid generator in the conductive composition for forming the back electrode. As such a conductive composition, a silane coupling agent precursor composition, a conductive polymer solution, and a specific acid generator can be used.

  The silane coupling agent precursor composition includes 5 to 40 parts by weight of a silane coupling agent, 50 to 90 parts by weight of a solvent, and 0.1 to 10.0 parts by weight of a diluted hydrochloric acid or acetic acid solution. It means what was obtained by reaction. The conductive polymer solution means a solution having a solid content of 0.1 to 5.0 wt% using a conductive polymer and a solvent.

  In the present invention, the reliability of the conductive composition is greatly improved by using a specific acid generator. As the acid generator, a material capable of generating an acid by heat is used, and it is preferable that the amine group is blocked at the time of charging the material. In addition, the acid generator that can be used in the present invention is widely used from a thermal acid generator (TAG, thermal acid generator) system in which the metal ion content is controlled to 2 ppm or less to a CXC grade that is controlled more than that. it can. Preferably, an acid generator capable of generating an acid at a soft baking temperature of 100 to 150 ° C. is used.

  Such acid generators include amine blocked, covalently blocked, metal blocked, and quaternary ammonium blocked thermal acid generators. one or more selected from the group consisting of (acid generator). As the acid generator, a product that can be dissolved or dissolved in a solvent (for example, IPA, PGME, or water) used in the present invention can be used.

  The acid generator is selected from the group consisting of dodecylbenzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, and derivatives thereof. One or more types can be used. The acid generator can be used up to all CXC and TAG grades of King industries.

  At this time, when reliability improvement is required in the conductive composition, the characteristics cannot be matched with the composition of the conventional electrode composition material, so the specific acid generator of the present invention, that is, TAG is added. Must be used.

  Further, when TAG is used due to the solvent composition and the conductive polymer characteristics, the material may be severely modified, so that it may be impossible to apply the composition not optimized. For example, the non-optimized back electrode material may make the TAG application impossible. By the way, since the specific acid generator used in the present invention is included in the optimized composition, it has a synergistic effect and can greatly contribute to improving the reliability.

  On the other hand, the silane coupling agent functions to improve the dispersibility of the conductive polymer in the composition. As the silane coupling agent, alkyloxysilane, aminosilane, vinylsilane, epoxysilane, methacryloxysilane, isocyanate silane, fluorine silane and the like can be used. More specifically, as the silane coupling agent, TEOS (tetraethyloxysilane), vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ- Aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, phenyltriethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, polyethylene oxide modified silane monomer, polymethylethoxysiloxane, Kisa include methyl disilacyclobutanes Jin, it may be used to select one or more.

  The silane coupling agent is preferably used in an amount of 5 to 40 parts by weight, and more preferably 10 to 30 parts by weight with respect to the entire conductive composition. When the content is less than 5 parts by weight, when the coating layer is formed, surface stains due to phase separation tend to appear, and the surface hardness may decrease. Increases and the stability of the composition decreases.

  The solvent used in the present invention is a group consisting of i) water, ii) an alcohol compound, and iii) propylene glycol monoethyl ether, dimethylformamide, acetylacetone, 1-methyl-2-pyrrolidinone, dipropylketone and ethyl lactate. One or more selected solvents.

  That is, the solvent used in the present invention is water or an alcohol compound, and water is used as a main solvent for hydrolysis of TEOS, and contains 10 to 50 parts by weight with respect to the entire solvent content. As the system compound, primary and secondary alcohols are mainly used, and an alcohol having a boiling point of 50 to 200 ° C. having 1 to 10 carbon atoms may be contained so as to be 10 to 50 parts by weight with respect to the entire solvent content. Alcohol is used as a solvent for maintaining the stability of Sol particles through stable hydrolysis and esterification after TEOS reaction. Further, in order to optimize the coating property, methoxy, ethoxy and propylethanol solvents having a boiling point of 100 to 160 degrees can be used, and 10 to 50 parts by weight can be included with respect to the total solvent content.

  The alcohol compound includes alcohol, diol or polyol, for example, methyl alcohol, ethyl alcohol, isopropanol, ethylene glycol, butanediol, neopentyl glycol, 1,3-pentanediol, 1,4-cyclohexanedimethanol, diethylene glycol. , Polyethylene glycol, polybutylene glycol, dimethylolpropane, trimethylolpropane, and one or more selected from the group consisting of these derivatives can be used.

  In the present invention, if necessary, halogens such as chloroform, dichloromethane, tetrachloroethylene, trichloroethylene, dibromoethane, dibromopropane; normal methylpyrrolidone, dimethyl sulfoxide; triethylamine, tributylamine, trioctylamine; cresol and the like are added as necessary. Can be used.

The solvent can solve the non-uniformity of the coating due to the difference in volatility generated during the surface coating, and can improve the surface resistance reliability by improving the film density of the TEOS coating film. Handle.
The solvent may be included in the remaining amount with respect to the entire composition, but it is preferably used in an amount of 50 to 90 parts by weight based on the total weight of the conductive composition.

  The diluted hydrochloric acid or acetic acid solution can be used to perform a sol-gel reaction involving hydrolysis in an acidic atmosphere. The diluted hydrochloric acid or acetic acid solution may be a 0.1 to 10% diluted hydrochloric acid or acetic acid solution diluted with water, but is not limited thereto. The hydrochloric acid or acetic acid dilution solution is used in an amount of 0.1 to 10.0 parts by weight with respect to the entire conductive composition.

In addition, a conductive polymer solution is used to produce the conductive composition of the present invention. As described above, the solid content is preferably 0.1 to 5.0 wt%. At this time, if the content of the solid content in the conductive polymer solution is less than 0.1% by weight, there is a problem of losing the role of the electrode, and if it exceeds 5% by weight, the TEOS Sol precursor composition and the aggregate ( aggregation) and gelation of the conductive polymer solution itself is promoted, which is difficult to manufacture.

The conductive polymer solution is used in an amount of 5 to 40 parts by weight with respect to the entire conductive composition. When the content of the conductive polymer solution is less than 5 parts by weight, the resistance rapidly increases, and when it exceeds 40 parts by weight, the permeability decreases, and the dispersion characteristics and the stability of the composition are maintained. It is hard to be done.
In such a conductive polymer solution, the solid content of the conductive polymer is 0.1 to 5% by weight and contains 95 to 99.9% by weight of the solvent, or 5 to 60% by weight and the solvent 40 to 95%. % By weight.
The conductive polymer used in the present invention is a basic substance that allows the composition of the present invention to have conductivity while being an organic substance.

  In order for the conductive polymer to have conductivity, a doping process is required. Such a process may be performed in a non-conductive powder form or a film form and then chemically doped or non-conductive. There is a method in which conductive powder and a dopant are mixed and dissolved in an organic solvent so as to have conductivity. Among these, the method using the said dopant can be used in this invention. Therefore, the conductive polymer is preferably used in a form mixed with a dopant, that is, a polymer obtained by doping a conductive polymer with a dopant substance.

  For example, as the conductive polymer, polyaniline, polypyrrole, polythiophene and derivatives thereof, or a polymer obtained by polymerizing a monomer (aniline, pyrrole, thiophene) derivative with a monomer, or the like can be used. At this time, as an example of a polymer obtained by polymerizing a derivative of the monomer with a monomer, poly (3,4-ethylenedioxythiophene) polymerized with 3,4-ethylenedioxythiophene, which is a thiophene derivative (poly ( 3, 4-ethylenediothiophene) and PEDOT). The PEDOT is stable in the air and has higher room temperature electrical conductivity than other polymers.

  In the present invention, such a conductive polymer includes dodecylbenzenesulfonic acid, toluenesulfonic acid, camphorsulfonic acid, benzenesulfonic acid, hydrochloric acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and salt compounds thereof. 2-sulfosuccinic acid ester salt, 5-sulfoisophthalic acid sodium salt, dimethyl-5-sodium sulfoisophthalate, 5-sodium sulfo-bis (β-hydroxyethyl) isophthalate and poly (4-styrenesulfonate) (PSS, It can be used for the production of a composition for forming an electrode in the form of a mixture further containing one or more dopants selected from the group consisting of poly (4-styrene sulfate). The dopant is preferably poly (4-styrene sulfonate).

  Therefore, the present invention can use PEDOT-PSS (also referred to as PEDOT: PSS) in which the PEDOT is doped with PEDOT during the production of the electrode-forming conductive composition, which can be used as an electrode or an antistatic material. Good coating properties and excellent interfacial properties and adhesion.

  In addition, according to the present invention, 0.1 to 1.0 part by weight of a surfactant can be further included with respect to 100 parts by weight of the entire conductive composition. The silicon-based surfactant can be used, but the type is not limited thereto.

  In addition, the present invention provides one or more binders selected from the group consisting of polyacrylic resins, polyurethane resins, epoxy resins, and polyester resins with respect to 100 parts by weight of the conductive composition as necessary. The resin may further include 0.1 to 30 parts by weight.

  On the other hand, according to the present invention, when the conductive composition is manufactured, the components (for example, a conductive polymer and a substance such as TEOS) added to the composition for forming the back electrode are collectively added as in the conventional case. Rather than using a method, a silane coupling agent (TEOS) is subjected to a sol-gel reaction at a high temperature to produce a precursor solution, and then a conductive polymer and an acid generator are mixed to form a conductive composition for electrode formation. It is characterized by manufacturing a product. Next, each step for producing the electrode-forming conductive composition will be described more specifically.

Manufacture of Silane Coupling Agent Precursor Composition In this stage, a precursor manufacturing process is performed through a sol-gel reaction of a silane coupling agent.
The conductive composition for electrode formation of the present invention can contain a conductive polymer, a dopant, a silane coupling agent, an acid generator and a solvent in the final composition, so that it can have such a composition. In the present invention, a process for producing a precursor solution using a silane coupling agent is performed.

  In other words, the present invention is excellent in the film state because the precursor obtained by the sol-gel reaction of the silane coupling agent different from the conventional production method is first produced and then mixed with the conductive polymer. In addition, it is possible to provide a conductive composition for forming an electrode that can exhibit excellent physical properties as compared with a conventional ordinary room temperature manufacturing method while satisfying a reliability interval depending on surface hardness and time.

  In particular, in the present invention, unlike the conventional method produced by polymerization of a conductive polymer and TEOS under normal temperature conditions, the precursor of the conductive composition for forming the back electrode produced by the sol-gel reaction of the silane coupling agent is used. Manufacture and use the body. Therefore, the present invention can increase the cross-linking level of the film itself in the finally obtained back electrode, and as a result, increase the surface density of the conductive polymer having the properties opposite to the hardness improvement. Thus, the amount of the conductive polymer used can be reduced, and the reliability can be improved by the conductive polymer relatively concentrated on the surface.

  As is well known, the sol-gel reaction is often used for the production of inorganic materials in which metal alkoxide is hydrolyzed and polycondensed in an alcohol solvent to synthesize a metal oxide or hydroxide form ceramic powder. Is the method. As the sol-gel reaction, a TEOS sol-gel method is known. Accordingly, in the present invention, focusing on such points, the sol-gel reaction of the silane coupling agent is performed, but the reaction is not allowed to proceed at room temperature, but the sol-gel reaction is performed at a temperature higher than room temperature. The crosslinkability can be increased during film formation on the metal, and the hardness can be improved. That is, in the present invention, when the silane coupling agent precursor composition obtained by the sol-gel reaction is combined with a conductive polymer described later, the dispersibility of the polymer is improved and the mechanical strength is improved. At the same time, the thermal properties can be improved, thereby providing an effect suitable for use in electronic materials. Such a structure can realize the properties that constitute an organic-inorganic hybrid composite material, thereby ensuring the rigidity and thermal excellence of the inorganic substance, and the flexibility and workability of the organic polymer substance. The physical properties such as can also be secured. Moreover, as a result of performing reliability evaluation after formation of a film, this invention confirmed reliability ensuring and the improvement of hardness.

  In the sol-gel reaction, a silane coupling agent precursor solution (for example, a TEOS sol solution) is produced by causing a silane coupling agent and a solvent to undergo a sol-gel reaction at a high temperature over a certain period of time.

  At this time, the high temperature mentioned in the present invention means a temperature higher than room temperature. Preferably, the sol-gel reaction is performed at a temperature of 40 to 70 ° C. for 1 to 5 hours. Most preferably, the sol-gel reaction is carried out at a temperature of 50 ° C. for 3 hours. Here, when the sol-gel reaction is less than 40 ° C., the hydrolysis level of TEOS may be lowered, and the additionally generated condensation reaction may be performed faster than the hydrolysis. Therefore, there can be problems with hardness and TEOS sol grain growth. Further, when the Sol-Gel reaction proceeds, if the temperature exceeds 70 ° C., a more reliable reaction can be promoted in terms of hydrolysis. However, the growth rate of the TEOS sol particles that have undergone hydrolysis and condensation reaction are excessively high. There is a problem that gelation is fast and rapid.

Further, in the step of producing the silane coupling agent precursor composition, a surfactant can be further added to allow the reaction to proceed.
Preferably, in the step of producing the silane coupling agent precursor composition, 0.1 to 1.0 part by weight of a surfactant is further added to 100 parts by weight of the silane coupling agent precursor composition. be able to.

Production of Conductive Composition for Forming Back Electrode In the present invention, conductive polymer solutions 5 to 40 having a solid content of 0.1 to 5.0 wt% are prepared after the silane coupling agent precursor composition is produced by the method described above. A step of adding and mixing 0.001 to 1.0 part by weight of an acid generator and an acid generator is performed to finally manufacture a conductive composition for forming a back electrode of a liquid crystal display device.

In this method, the silane coupling agent precursor composition and the conductive polymer can be mixed at a temperature of 10 to 40 ° C.
The conductive composition for forming the back electrode of the final liquid crystal display device manufactured by the above-described method is composed of 5 to 40 parts by weight of a conductive polymer solution having a solid content of 0.1 to 5.0 wt%; a silane coupling agent 3 to 30 parts by weight; solvent 20 to 60 parts by weight; and acid generator 0.001 to 1.0 parts by weight.

  In the final electrode-forming conductive composition, when the content of the conductive polymer is less than 5 parts by weight, the resistance increases rapidly, and when it exceeds 40 parts by weight, the transmittance decreases, Dispersion characteristics and composition stability are difficult to maintain.

  The silane coupling agent is preferably contained in an amount of 3 to 30 parts by weight, more preferably 5 to 20 parts by weight, based on the final electrode forming composition of the present invention. When the content is less than 3 parts by weight, when the coating layer is formed, surface stains due to phase separation tend to appear, and the surface hardness may decrease. Increases and the stability of the composition decreases.

  The solvent is preferably contained in an amount of 20 to 60 parts by weight with respect to the final electrode forming composition of the present invention. When the content is less than 20 parts by weight, the stability of the composition is lowered, and when it exceeds 60 parts by weight, not only the resistance is high, but also the material is vulnerable to impact.

  The conductive composition of the present invention comprising the above components can further contain the above-described binder resin, if necessary. As the binder resin, a polyacrylic resin, a polyurethane resin, an epoxy resin, a polyester resin, or the like can be used, and the content thereof is 0.1 to 30 weights at the maximum with respect to 100 parts by weight of the conductive composition. May further be included.

Meanwhile, according to another embodiment of the present invention, a back electrode for a liquid crystal display device formed by applying the above-described conductive composition is provided.
The electrodes described in the present invention usually include not only the back electrode of the liquid crystal display device but also all the conductive polarizing plate coating films (Korean Registered Patent No. 059329) that can replace the conventional back electrode. Preferably, the conductive composition of the present invention can be used for back electrode formation.

The method of forming the back electrode may include a step of coating a heat-treating composition for forming a back electrode according to the above-described method on an electrode formed on a substrate and performing a heat treatment.
In the method for forming the back electrode of the liquid crystal display device, a normal coating method can be applied. For example, a spray method, a bar coating method, a doctor blade method, a roll coating method, a dipping method, etc. The following coating methods can be applied.

  The coating is preferably performed on a substrate to a thickness of 0.5 to 1 μm, and then is soft-baked on an internal and external hot plate at 100 ° C. to a thickness of 300 to 500 nm. The back electrode of the liquid crystal display device is formed by forming a film layer.

  Such a conductive composition for electrode formation of the present invention can improve the transmittance of the back electrode by optimizing the dispersity of the conductive polymer in the composition. Further, if the conductive composition of the present invention can be coated so that there are no defects on the adhesive surface with the substrate, the transmittance can be dramatically improved. Moreover, the back electrode coated with the conductive composition of the present invention is also excellent in surface hardness.

[Example]
Hereinafter, preferred examples will be presented for the understanding of the present invention. However, the following examples are merely illustrative of the present invention, and the scope of the present invention is not limited to the following examples.

Example 1
TEOS (tetraethyloxysilane) 15 parts by weight, IPA (isopropyl alcohol) 9 parts by weight, propylene glycol monomethyl ether 13 parts by weight, water 26 parts by weight, acetylacetone 5 parts by weight, 5.0% acetic acid diluted solution (aqueous solution) 1 part by weight And the sol-gel reaction was carried out at 50 ° C. for 3 hours.
Thereafter, the silane coupling agent precursor composition obtained by the reaction was mixed with 30 parts by weight of a conductive polymer solution having a solid content of 2.0 wt% with respect to 100 parts by weight of the composition and an amine-capped thermal acid. 1 part by weight of a generator (Amine blocked thermal acid generator, TAG 2713S from King Industries) was added and mixed to prepare a conductive composition for forming a back electrode of a liquid crystal display device.
At this time, the conductive polymer solution contains 2% by weight of a solid content conductive polymer (EDOT monomer and PEDOT / PSS produced by polymerization of PSSA used as a dopant) and 98% by weight of water.

Example 2
TEOS (tetraethyloxysilane) 15 parts by weight, IPA (isopropyl alcohol) 9 parts by weight, propylene glycol monomethyl ether 13 parts by weight, water 26 parts by weight, acetylacetone 5 parts by weight, 5.0% acetic acid diluted solution (aqueous solution) 1 part by weight And the sol-gel reaction was carried out at 50 ° C. for 3 hours.
Thereafter, in the silane coupling agent precursor composition obtained by the reaction, 30 parts by weight of a conductive polymer solution having a solid content of 2.0 wt% as in Example 1 with respect to 100 parts by weight of the composition; A conductive composition for forming a back electrode of a liquid crystal display device was prepared by adding 1 part by weight of an amine-blocked thermal acid generator (CXC 1820 from King Industries).

Example 3
TEOS (tetraethyloxysilane) 15 parts by weight, IPA (isopropyl alcohol) 9 parts by weight, propylene glycol monomethyl ether 13 parts by weight, water 26 parts by weight, acetylacetone 5 parts by weight, 5.0% acetic acid diluted solution (aqueous solution) 1 part by weight And the sol-gel reaction was carried out at 50 ° C. for 3 hours.
Thereafter, in the silane coupling agent precursor composition obtained by the reaction, 30 parts by weight of a conductive polymer solution having a solid content of 2.0 wt% as in Example 1 with respect to 100 parts by weight of the composition; 1 part by weight of an amine-blocked thermal acid generator (TAG 1863 from King Industries) was added and mixed to prepare a conductive composition for forming a back electrode of a liquid crystal display device.

Example 4
TEOS (tetraethyloxysilane) 15 parts by weight, IPA (isopropyl alcohol) 9 parts by weight, propylene glycol monomethyl ether 13 parts by weight, water 26 parts by weight, acetylacetone 5 parts by weight, 5.0% acetic acid diluted solution (aqueous solution) 1 part by weight And the sol-gel reaction was carried out at 50 ° C. for 3 hours.
Thereafter, in the silane coupling agent precursor composition obtained by the reaction, 30 parts by weight of a conductive polymer solution having a solid content of 2.0 wt% as in Example 1 with respect to 100 parts by weight of the composition; 1 part by weight of an amine-blocked thermal acid generator (TAG 2712 from King Industries) was added and mixed to prepare a conductive composition for forming a back electrode of a liquid crystal display device.

Example 5
TEOS (tetraethyloxysilane) 15 parts by weight, IPA (isopropyl alcohol) 9 parts by weight, propylene glycol monomethyl ether 13 parts by weight, water 26 parts by weight, acetylacetone 5 parts by weight, 5.0% acetic acid diluted solution (aqueous solution) 1 part by weight And the sol-gel reaction was carried out at 50 ° C. for 3 hours.
Thereafter, 30 parts by weight of a conductive polymer solution having a solid content of 2.0 wt% as in Example 1 and a quaternary ammonium-blocked thermal acid were added to the silane coupling agent precursor composition obtained by the above reaction. A conductive composition for forming a back electrode of a liquid crystal display device was prepared by adding 1 part by weight of a generator (Quaternary Ammonium Blocked thermal acid generator, King Industries CXC 1613).

Comparative Example 1
TEOS (tetraethyloxysilane) 15 parts by weight, IPA (isopropyl alcohol) 9 parts by weight, propylene glycol monomethyl ether 13 parts by weight, water 27 parts by weight, acetylacetone 5 parts by weight, 5.0% acetic acid diluted solution (aqueous solution) 1 part by weight And the sol-gel reaction was carried out at 50 ° C. for 3 hours.
Thereafter, a conductive composition is prepared by adding 30 parts by weight of a conductive polymer solution having a solid content of 2.0 wt% similar to that in Example 1 to the silane coupling agent precursor composition obtained by the above reaction. did. At this time, the conductive polymer solution contains 2.0 wt% of a solid content conductive polymer (PEDOT / PSS produced by polymerization of PSSA used as an EDOT monomer and a dopant) and 98 wt% of water.

Experimental Example Each conductive composition of Examples 1 to 5 and Comparative Example 1 was applied to an electrode formed on a substrate to a thickness of 0.5 μm, and then soft-baked on a hot plate at 120 ° C. for 600 seconds. A film layer having a thickness of 300 nm was formed.
The following method was used for the reliability evaluation of the conductive material for forming the back electrode coated on the substrate. The results are shown in Table 1.
The reliability at normal temperature was evaluated under conditions of normal temperature and humidity (Rh 50% or less). The high temperature reliability was evaluated while standing in an oven at 80 ° C. The high temperature / high humidity reliability used a high temperature and high humidity oven of 65 ° C. and Rh 90%. The surface resistance of the substrate was evaluated over 500 hours using SIMCO ST-4 equipment.

As shown in Table 1, in the case of Examples 1 to 5 using TAG (acid generator), the reliability of normal temperature and high temperature and high temperature and high humidity after 500 hours as compared with Comparative Example 1 using no acid generator. Excellent results were shown. In particular, the results of Examples 1 and 2 appeared to ensure the most excellent reliability.
However, it can be seen that Comparative Example 1 has poor reliability and is not suitable for electrode formation.

Claims (14)

5 to 40 parts by weight of a silane coupling agent,
50 to 90 parts by weight of solvent,
0.1 to 10.0 parts by weight of dilute hydrochloric acid or acetic acid solution,
5 to 40 parts by weight of a conductive polymer solution having a solid content of 0.1 to 5.0 wt%; and
0.001 to 1.0 part by weight of an acid generator;
A conductive composition for forming a back electrode of a liquid crystal display device.   The acid generator may be an amine blocked, a covalent blocked, a metal blocked, and a quaternary ammonium blocked thermal acid generator. The conductive composition according to claim 1, which is at least one selected from the group consisting of:   2. The conductive composition according to claim 1, wherein the acid generator is one or more selected from the group consisting of dodecylbenzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, and derivatives thereof.   The solvent is selected from the group consisting of i) water, ii) alcohol compounds, and iii) propylene glycol monoethyl ether, dimethylformamide, acetylacetone, 1-methyl-2-pyrrolidinone, dipropyl ketone and ethyl lactate 1 The electroconductive composition for back electrode formation of the liquid crystal display device of Claim 1 containing a solvent of a seed | species or more.   The alcohol compound is methyl alcohol, ethyl alcohol, isopropanol, ethylene glycol, butanediol, neopentyl glycol, 1,3-pentanediol, 1,4-cyclohexanedimethanol, diethylene glycol, polyethylene glycol, polybutylene glycol, dimethylol. The conductive composition according to claim 4, which is one or more selected from the group consisting of propane, trimethylolpropane, and derivatives thereof.   The conductive composition according to claim 1, wherein the conductive polymer solution has a solid content of the conductive polymer of 0.1 to 5% by weight and includes 95 to 99.9% by weight of a solvent.   The conductive composition according to claim 6, wherein the conductive polymer includes one or more selected from the group consisting of polyaniline, polypyrrole, polythiophene, and derivatives thereof.   The conductive composition according to claim 6, wherein the conductive polymer includes poly (3,4-ethylenedioxythiophene).   The conductive polymer is dodecylbenzenesulfonic acid, toluenesulfonic acid, camphorsulfonic acid, benzenesulfonic acid, hydrochloric acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, their salt compounds, 2-sulfosuccinic acid. 1 selected from the group consisting of ester salts, sodium 5-sulfoisophthalate, dimethyl-5-sodiumsulfoisophthalate, 5-sodiumsulfo-bis (β-hydroxyethyl) isophthalate and poly (4-styrenesulfonate) The conductive composition according to claim 8, further comprising one or more dopants.   The conductive composition according to claim 6, wherein the conductive polymer is poly (3,4-ethylenedioxythiophene): poly (4-styrenesulfonate) (PEDOT: PSS).   The silane coupling agent is selected from the group consisting of alkyloxysilanes having 1 to 20 carbon atoms, aminosilanes, vinylsilanes, epoxysilanes, methacryloxysilanes, isocyanate silanes, and fluorine silanes. The electrically conductive composition of Claim 1 which is 1 or more types.   The conductive composition according to claim 1, further comprising 0.1 to 1 part by weight of a surfactant based on 100 parts by weight of the total composition. With respect to 100 parts by weight of the conductive composition,
2. The conductive composition according to claim 1, further comprising 0.1 to 30 parts by weight of one or more binder resins selected from the group consisting of a polyacrylic resin, a polyurethane resin, an epoxy resin, and a polyester resin. .   A back electrode for a liquid crystal display device formed by applying the conductive composition according to claim 1.