TWI280077B - Ag paste composition for microelectrode formation and microelectrode formed using the same - Google Patents

Abstract

Provided are a high viscosity Ag paste composition and a microelectrode formed using the Ag paste composition. The Ag paste composition includes (a) 60 to 80 wt% of Ag powders, (b) 1 to 10 wt% of an inorganic binder, (c) 0.001 to 1 wt% of a stabilizer, and (d) 15 to 35 wt% of a negative photoresist composition that disperses conductive micro-powders and is soluble in an alkaline. The Ag paste composition can be applied in a sintering process of less than 600 DEG C and thus is suitable for PDP fabrication. Also, because of high viscosity, the Ag paste composition is suitable for microelectrode formation and has good printing property. In addition, because a surfactant and an organic solvent are not separately used, the Ag paste composition can be prepared simply and economically, and is environmental friendly.

Description

1280077 玖 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 发明 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 .

L·U BACKGROUND OF THE INVENTION Recently, various graphic technologies have been developed as the demand for large-sized, high-density, high-accuracy, and high-reliance display devices has increased. Similarly, research on compositions for microelectrodes that are compatible with these patterning techniques has been actively pursued. The plasma display panel (hereinafter referred to as "PDP") has advantages over the liquid crystal panel, such as a fast reaction speed and a large size, and therefore, it has been used in different regions. Electrodes for PDPs have traditionally been fabricated using a screen printing method to pattern an electrode material. However, conventional screen printing methods require a lot of techniques, and during screen printing, the paste flows on the substrate due to low viscosity. As such, due to the low precision of the screen, it is difficult to achieve the high precision, large screen pattern required in the PDP. In addition, conventional screen printing methods have the disadvantage of causing short-circuiting or separation by the screen during the printing period 20 and the sintering temperature such as i, oo 〇 °c or south. Recently, photolithographic lithography processes using a photosensitive resin composition to conform to a large area and which can be used for a high-accuracy electrode circuit have been developed. The photolithography lithography process is a method of forming a desired pattern of 1280077 by printing a photosensitive resin composition in which a conductive fine powder is dispersed to form a thick film of a uniform sentence and is formed using a desired shape. The mask exposes the thick film thus formed, followed by development with an alkaline developer. The miscible compatibility between the photosensitive fine composition and the end of the conductive (four), the adhesion between the photosensitive resin composition and the glass substrate during development, and the heat resistance of the photosensitive resin composition during sintering. As a very important factor, it must be considered when forming a high-accuracy electrode circuit. Similarly, the conductive fine powder (which is an inorganic material) in which the average sentence is dispersed requires a high viscosity of 3, _cP or more in the organic photosensitive resin composition to allow 1 --cutting stress. The photosensitive resin composition also needs to be stable against external forces (such as static electricity on the surface of the conductive fine powder) to maintain a uniform state of dispersion, a polymer resin having a low crystallinity, and a glass surface to be required. Good adhesion and need to have good thermal decomposition properties. Conventional photosensitive conductive pastes can be sintered at 8 Torr or higher. In this example, the conventional photosensitive conductive paste is not suitable for the production of a PDP because sodium carbonate glass is usually used (its sintering temperature must be maintained at 600 ° C or lower). Similarly, in the case of sintering a conventional photosensitive conductive paste at 60 °C or lower, a problem of generation of a sintered residue and a decrease in electrical conductivity occurs. 20 Regarding Conductance Dispersed in a Photosensitive Resin Composition Powder, the traditionally widely used gold (Au) and copper (Cu) powders are treated with individual organic solvents to develop after exposure, but this will cause environmental pollution. Similarly, Αι and Cu powders are expensive. And the problem of high sintering temperature. Further, 'a commercially available photosensitive resin composition (which is a 1280077 low-viscosity conductive paste having 500 to 1,500 cP, which uses a plate-shaped Ag powder), The Ag powder has poor dispersion characteristics due to its plate-like form. Even when a spherical Ag powder is used, a large average particle size of from a micron to several tens of micrometers may occur, which causes a problem that it is difficult to form a micropattern. SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a high viscosity silver paste composition for forming a microelectrode. It is applied in a sintering process at 600 ° C or lower. Similarly, due to the high viscosity of 10, the silver paste composition is suitable for forming an accurate microelectrode which cannot be formed by a conventional screen printing method, and the composition It has good printing properties. In addition, since the surfactant and the organic solvent are not separately used, the silver paste composition can be prepared simply and economically and it does not pollute the environment. Brief Description of the Drawing 15 Figure 1 shows the development by Scanning electron micrograph (SEM) of a 50 micron pattern formed by the silver paste composition according to the present invention; Fig. 2 is a SEM after developing a 50 micron pattern formed by the silver paste composition according to the present invention Section 3; FIG. 3 is an SEM image after sintering a 20 50 micron pattern formed from the silver paste composition according to the present invention; and FIG. 4 is a 50 formed by sintering the silver paste composition according to the present invention. SEM cross section after micron pattern I: Embodiment 3 Detailed description 1280077 According to the present invention, a high viscosity silver paste composition for forming a microelectrode has been provided, which comprises: a) 60 to 80 weights/c ^Ag powder; b) 1 to 10% by weight of an inorganic binder; 5 c) 0.001 to 1% by weight of a stabilizer; and d) 15 to 35% by weight of a negative photoresist composition which is capable of dispersing a conductive fine powder and is soluble in the test. In the silver paste composition for forming a microelectrode, the negative photoresist composition comprises: 10 a) 30 to 70% by weight of an acrylate copolymer photoresist represented by the following formula 1: Formula 1 R3 - f- CH2——C—I-hCH2——C—1—

\ I XT |X COORi COOR2 wherein Ri can be hydrogen, phenyl, benzyl, nitro substituted phenyl, 15 halogen substituted phenyl, nitro substituted benzyl, CiSCw alkyl or hydroxy a substituted alkyl group of CiSCw; R2 may be an ethylhexyl, isobutyl, tert-butyl, octyl, 3-methoxybutyl or methoxypropanediol group; R3 may be hydrogen or methyl; Is hydrogen or methyl; an integer of 8 to 40; n2 is 1 or 2; or the following formula 2: Formula 2 8 20 1280077 R7 R4

Wherein R5 may be hydrogen or a thiol group; R6 may be a phenyl, fluorenyl or - oxime COCH3 group; R7<is hydrogen or a -ch2cooh group; "^, Han 丨 and 叱 are as defined above; 5 b) l 〇奚 40% by weight of photopolymerizable monomer; c) 0.5 lings by weight of photopolymerization initiator; d) om 〇 weight. / anti-foaming agent; and % by weight of leveling agent. According to another aspect of the present invention, there has been provided a microelectrode formed using the silver paste group. Hereinafter, the silver paste composition of the present invention will be described in more detail. The present invention provides a high-viscosity silver paste composition for forming a microelectrode comprising: a) 60 to 80% by weight of Ag powder; 丨 to (7)% by weight of the machine bonding, c) 0.001 to 1% by weight a stabilizer; and a negative photoresist composition of 15% by weight to % by weight, which disperses the conductive fine powder and is soluble in the base. The conductive fine powder as used herein is an Ag powder. The Ag powder is used in the silver-polymerized composition in an amount of from 6 Torr to 80% by weight, preferably so as to be 〇/〇〇. If the content of the Ag powder is less than 60% by weight, the density of the cerium powder is reduced by 20%. Therefore, the surface porosity of the surface after pattern formation and sintering is increased. The result will cause an increase in resistance and a short circuit. Similarly, due to the low viscosity, the silver 1280077 slurry: composition will flow over the glass substrate during printing. On the other hand, if the content of the Ag powder exceeds 80% by weight, the problem of printing which cannot be printed on the glass substrate or the glass substrate cannot be separated from the screen mask may occur due to excessive | Similarly, a low smoothness of 5 degrees after printing can cause local thickness differences and screen marks of the screen mask. In addition, when

When the density of the Ag powder is increased, the phenomenon of "cutting is deteriorated." The shape of the Ag powder to be used is not limited. However, as for the dispersion characteristics, spherical Ag powder is preferable. The average particle size range of the Ag powder is preferably 〇· 3 to 3 μm, more preferably 0.5 to 2 μm, most preferably 0.6 to 1.3 μm. The purity of the 1 〇Ag powder is preferably 96% or more, more preferably 98% or more. When the purity of the Ag powder is reduced, the electrical resistance is increased after sintering due to impurities. "The silver paste composition of the present invention includes the inorganic binder to sinter and adhere the U-electrode to the glass substrate. The inorganic binder is used in an amount of from 5% by weight to about 5% by weight, based on the total weight of the composition of the silver paste. The content of the inorganic binder on the right is less than! At the weight %, the adhesion between the substrate and the electrode after sintering is reduced, so that the electrode is separated. / When the content of the right binder is more than 1% by weight, the electrode resistance after sintering may increase or cause a short circuit. , ", the money tanning agent is preferably one or more selected from the group consisting of the following, the acid ^ ^ 物 · · si 〇 2 · 4 2 3 Sl 〇 2. M2 〇 ' where M is a divalent metal ion And Μ, is a monovalent metal ion. 20 1280077 The inorganic binder may have a spherical shape, but is not limited thereto. The inorganic binder preferably has an average particle size ranging from 0.3 to 3 μm, more preferably from 0.5 to 2 μm. The optimum is 〇·6 to I·3 μm. The inorganic binder has a glass transition temperature (Tg) of preferably 360 to 500 ° C and a glass softening temperature (Ts) of 400 to 550 ° C. If the glass is converted When the temperature and the glass softening temperature are respectively lower than 360 ° C and 400 ° C, the sintering of the inorganic binder will initially exhibit a state in which the organic material is not completely decomposed. Therefore, an organic material may exist in the pattern. Therefore, the performance of the pattern is lowered. On the other hand, if the glass transition temperature and the glass softening temperature exceed 500 ° C and 55 (TC, respectively, the sintering of the inorganic binder may be incomplete. Therefore, in the microelectrode and The adhesion between the glass substrates will be reduced, the pattern features will be deteriorated, and Pattern separation. 15 It is preferred to store the inorganic binder at a moisture-free position because moisture absorbed in the inorganic binder promotes gelation of the paste composition. Preferably, the probiotic binder is dried at a temperature of 80 to 35 Torr so that foreign substances do not adhere to the surface of the inorganic binder. If the heat exchanger is stored at a temperature higher than 35 〇 ° C (this It is higher than its conversion, and it is produced in the second place. The second component prevents the _ composition f storage % qualitative and controls the development rate. The usage amount is the weight % of the tongue and dandruff, preferably 0.005 to 1 weight 0 / 畀〇 · 〇1 to 0·6 weight. /, preferably 0' is based on the total weight of the silver paste composition. 1280077 If the content of the stabilizer is less than 0.001% by weight, the paste is prone to gelation. On the other hand, if it exceeds 1% by weight, the viscosity of the composition may be lowered or the pattern may not be formed. Generally, an antioxidant (for example, benzotriazole, ascorbic acid, phosphoric acid, or arsenic) may be used. Phosphoric acid or a salt thereof is used as a stabilizer, but is not limited thereto. Silver of the present invention The composition includes the negative photoresist composition which can easily disperse the conductive fine powder (such as Ag powder) due to high viscosity, and can be developed at high speed in an alkaline developer. The negative photoresist composition is used in an amount of 15 to 35% by weight, preferably 20 to 35% by weight and most preferably 25 to 35% by weight, based on the total weight of the silver paste composition. If the content of the negative photoresist composition exceeds 35% by weight Then, holes are formed in the electrode during electrode formation. As a result, the electrode impedance is increased, so that a short circuit occurs during driving of the circuit. On the other hand, if it is less than 15% by weight, it is difficult to obtain a desired electrode. pattern. The negative photoresist composition preferably comprises: a) 30 to 70% by weight of an acrylate copolymer photoresist represented by the following formula 1: Formula 1 R3

COORi COOR2 20 wherein Ri may be hydrogen, phenyl, benzyl, nitro substituted phenyl, halogen substituted phenyl, nitro substituted benzyl, fluorenyl to hydrazine or hydroxy 12 1280077 based Substituted 01 to (31()alkyl; R2 may be ethylhexyl, isobutyl, tert-butyl, octyl, 3-decyloxybutyl or methoxypropanediol groups; R3 may be hydrogen or Methyl; R4 may be hydrogen or methyl; ~ is an integer from 8 to 40; 112 is 1 or 2; or Formula 2 below:

Wherein R5 may be hydrogen or a carboxyl group; the compound 6 may be a phenyl group, a carboxyl group or a -〇COCH3 group; R? may be a hydrogen or a -CH2COOH group; ^, ^, ~ and 叱 are as defined above; b) 10 to 40% by weight of photopolymerizable monomer; c) 0.5 to 10 parts by weight. / 〇 photopolymerization initiator; d) 0.1 to 1% by weight of an anti-foaming agent; and e) 0.1 to 1% by weight of a leveling agent. The acrylate copolymer of Formula 1 has a viscosity of 丨〇, _ to 2 〇, _cp and 15 of 1 is 15 and preferably 〇〇〇 to 50,000, more preferably 25,000 to 30,000. Similarly, with regard to the printing method, the glass transition temperature of the acrylic vinegar copolymer is preferably 1 〇〇 C or higher. If the glass transition temperature is lower than 100 ° C, printing-related problems occur due to strong adhesion. 20 and an acrylic monomer other than a carboxylic acid, an aromatic monomer, or a self-plasticized monomer. Self-plasticizable monomers and examples of monomers which can be used to prepare the acrylate copolymer in addition to the self include unsaturated carboxylic acids, aromatics, A A______ 13 1280077, unsaturated carboxylic acids can be used to provide the A composition that is soluble in alkali. Examples of the unsaturated carboxylic acid include acrylic acid, mercaptopropionic acid, decomposed aconitic acid, maleic acid, fumaric acid, vinyl acetic acid, and anhydrides thereof. The unsaturated carboxylic acid is preferably used in an amount of from 20 to 50% by weight based on the total weight of the acrylate copolymer 5. When the content of the unsaturated decanoic acid exceeds 50% by weight, gelation tends to occur during the polymerization, the degree of polymerization is difficult to be adjusted, and the storage stability of the resin composition during exposure is lowered. On the other hand, if the content of the unsaturated carboxylic acid is less than 20% by weight, it is necessary to increase the development time. 10 The aromatic monomer can be used to provide a pattern formed by adhesion to the glass surface during development and stabilization. Examples of the aromatic monomer include styrene, benzyl methacrylate, benzyl acrylate, phenyl acrylate, phenyl methacrylate, 2- or 4-nitrophenyl acrylate, methacrylic acid or 4-nitro Benzene vinegar, thioglycol 2- or 4-fluorenyl sulphate, acrylic acid 2_ or 4- chlorobenzene vinegar 15 and methyl propylene g & 2 or 4 chlorobenzene g. The aromatic monomer is preferably used in an amount of 15 to 45% by weight, more preferably 4% by weight, based on the total weight of the copolymer. If the content of the aromatic monomer exceeds % by weight, it is necessary to increase the development time. Also, since the heat resistance is increased, the photosensitive resin is left during sintering, thus reducing the intrinsic electrode characteristics. On the other hand, the content of the aromatic monomer is less than 15% by weight, and the adhesion to the surface of the glass during development is lowered. As a result, pattern separation and texture straightness are liable to occur, which results in difficulty in obtaining a stable pattern. In particular, the self-plasticizable monomer is provided to adjust the degree of polymerization and to reduce crystallinity. Examples of the self-plasticizable monomer include (meth)acrylic acid 2_ 14 1280077 ethylhexyl ester, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, and octyl (meth)acrylate. , 3-methoxybutyl (meth)acrylate and methoxypropylene glycol (meth)acrylate. The self-plasticizable monomer is preferably used in an amount of from 3 to 15% by weight, more preferably from 5 to 10% by weight, based on the total weight of the acrylate copolymer. If the content of the self-plasticizable monomer exceeds 15% by weight, pattern separation may deteriorate during development and pattern flatness may decrease. On the other hand, if the content of the self-plasticizable monomer is less than 3% by weight, the degree of polymerization increases, and gelation is caused. Even when gelation does not occur, the formed pattern is easily damaged after development. 10 An acrylate monomer other than the self-plasticizable acrylate monomer is provided to adjust the glass transition temperature, adhesion to the substrate, and polarity of the acrylate copolymer. Examples of the acrylate monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxyoctyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, and n-butyl acrylate. . The acrylate monomer is preferably used in an amount of 10 to 30% by weight, based on the glass transition temperature of 15 degrees, the heat resistance, and the hydrophilicity of the developer of the acrylic acid ester copolymer, with the total of the acrylate copolymer. The weight will prevail. The acrylate copolymer can be obtained by polymerizing the above-described four monomers in a solvent having a polarity which can appropriately prevent gelation of the monomer. Preferable examples of the solvent include carbitol acetate, r-butyrolactone, diethylene glycol butyl ether, trimethyl pentylene glycol monoisobutyrate, and dipropylene glycol monoethyl ether. The acrylate copolymer resin of the formula 1 or 2 is used in an amount of from 30 to 70% by weight. If the content of the acrylate copolymer is less than 30% by weight, pattern formation becomes difficult. If it exceeds 70% by weight, the dispersion characteristics of the powder may deteriorate. 15 1280077 In the negative photoresist composition, the photopolymerization initiator may be one or a mixture of the following: trimorph, diphenyl ketone, acetamidine, imidazole, and thioxanthone. Examples of the photopolymerization initiator include 2,4-bistrismethyl-6-p-methoxystyryl-s-trisyl, 2-p-methoxystyryl-5-4, 6-bistrimethylmethyl-s-three tillage, 2, 'trichloromethyl-6-trione, 2,4-trichloromethyl-4-methylnaphthyl-6-tris, diphenyl Ketone, p-(diethylamino)diphenyl ketone, 2,2-dichloro-4-phenoxyethyl hydrazine, 2,2,-diethoxyethyl benzene, 2,2,- Dibutylphenoxyacetam, 2-hydroxy-2-methylpropenzene, p-tertiary butyl triethylene acetophenone, p-tertiary butyl dichloroacetam, benzene, 4,4,- Ethylaminodiphenyl 10 ketone, thioxanthone, 2-air thioxanthone, 2-methylthioxanthone, 2-isobutylthioxanthone, 2-dodecylxanthone, 2, 4-dimethylthioxanthone, and 2,4-diethylthioxanthone-2,2'-bis_2-chlorophenyl_4,5,4',5'-tetraphenyl-2' -1,2'_biimidazole. The photopolymerization initiator is preferably used in an amount of from 0.5 to 10% by weight, more preferably from 2 to 4% by weight. If the content of the photopolymerization initiator is more than 1% by weight, the storage stability is lowered, and the pattern separation during development is deteriorated due to the high degree of hardening. On the other hand, if it is less than 5% by weight, normal pattern formation becomes difficult and pattern flatness is deteriorated due to low sensitivity. In the negative photoresist composition, the photopolymerizable monomer may be one or a mixture of a polyfunctional acrylate derivative. Examples of the photopolymerizable mono-2-steroid include: 1,4-butanediol dipropionate, ι,3-butylene glycol diacrylate, ethylene glycol diacrylate, diganyl dipropionate Alcohol ester, diethylene triacrylate, dipropyl benzoic acid, dipentaerythritolkisacrylate, diisopentyl hydroxypentaacrylate, dipropionate Acid glyceride, trimethyl methacrylate trimethyl propyl acrylate, 16 1280077 isopentenyl methacrylate, pentaerythritol dimethacrylate, ditol trimethyl acrylate, diacrylic acid Bisphenol A ester derivative, trishydroxypropyl propane triacrylate and polyisoprenyl acrylate. The photopolymerizable monomer is preferably used in an amount of from 1 to 40% by weight, more preferably from 20 to 30% by weight. If the content of the photopolymerizable monomer exceeds 40% by weight, the pattern is separated during development and the flatness of the pattern is deteriorated due to the high degree of hardening. On the other hand, if it is less than 1% by weight, normal pattern formation becomes difficult and pattern flatness is lowered due to low sensitivity and low degree of hardening. Meanwhile, at the time of coating using a printing method, microbubbles are generated during mixing of the Ag powder with its component. The microbubbles present in the thick film due to high viscosity are converted into pinholes during sintering, thus causing electrode separation. An anti-foaming agent of the negative photoresist composition can be provided to prevent separation of the electrode. The leveling agent is provided to reduce the miscibility between the Ag powder and the photoresist composition due to the surface tension of the photoresist composition, and to reduce the problem caused by the lack of uniformity of the film. Examples of the leveling agent include an anionic copolymer and an aralkyl group-modified polydecylalkyl oxane. Examples of the anti-foaming agent include a polyester-modified polymethyl carbazide, a polyoxan, a non-stone substrate polymer compound, a modified urea solution, and a polyester. Modified dimethyl polyfluorene gas 20 and dimethyl polyoxo copolymer modified by poly S. The amount of the emulsion anti-foaming agent and the leveling agent used is preferably from 0.1 to 1% by weight. The use of more than 10% by weight of the anti-foaming agent and the leveling agent leaves the remaining film during development. If the content of the anti-foaming agent and the leveling agent is less than 01% by weight 0/0, the desired characteristics are not easily obtained.里 17 1280077 The silver paste composition of the present invention can be prepared by premixing an Ag powder, an inorganic binder, a stabilizer, and a negative photoresist composition as described above using a planetary mixer, and using a grinder (such as 3). - Roller pulverizer) uniformly disperses the Ag powder, the inorganic binder and the stabilizer in the photoresist composition to form a 5-paste phase. The silver paste composition thus prepared has a viscosity of 3, 〇〇〇 to 60,000 cP, and has pseudoplastic properties. These features allow the silver paste composition to be used as a composition for forming microelectrodes that require low stress resistance, improved printing characteristics (although having a south viscosity) and during printing. High smoothness after printing. According to another aspect of the present invention, there has been provided a microelectrode formed using the silver paste composition. The microelectrode can be formed by a micropattern forming step and a sintering step. In the micropattern forming step, a silver paste composition prepared as described above is printed on the base using a screen printing machine using a mesh mask such as SUS 325 mesh and SUS 400 mesh. On the surface of the material. At a temperature of 80 to 12 〇. The coated sample is dried in a convection oven for 10 to 4 minutes. The thus formed silver paste coated film is exposed to a light source (such as a mercury lamp) containing a complex wavelength of 365 nm to form a pattern. Then, using an appropriate developer (such as NaAO3 solution, KOH, and hydrazine II), it was developed at room temperature to 刈.

20 In the sintering step, the micropattern formed above is sintered in an electric furnace at 500 to 6 ° C for 10 to 60 minutes. During the sintering, in order to completely remove the negative photoresist composition, the micropattern was maintained at a temperature of about 3 〇〇s 4 〇〇 t: Ti 〇s for 60 minutes. When the photoresist composition is not completely removed, the organic material of the photoresist composition exists as a carbonate, and thus the (10) minute 1280077 is not completely sintered. Similarly, the resistance will increase after sintering or the micropattern will become dielectric. Furthermore, microcracks are generated in the micropattern after sintering. Hereinafter, the invention will be more specifically illustrated by way of examples. However, the following examples are provided for clarification only, and thus the invention is not limited thereto or limited thereto. Values show % by weight unless otherwise specified in the examples. EXAMPLES Examples 1 to 4 Preparation of acrylate copolymer photoresist which can disperse conductive fine powder and alkali-soluble negative photoresist composition 10 According to the following composition and content in Table 1, the preparation was carried out by polymerization. An acrylate copolymer of 1. Here, as a solvent used for the polymerization, 50% by weight of T-butyrolactone (GBL) was used in Examples 1 to 3, and 50% by weight of dipropylene glycol monoethyl ether (DPGME) was used in Example 4. ). 15 Table 1 Part Example 1 Example 2 Example 3 Example 4 Benzyl methacrylate (mol%) 35 30 41 41 Mercaptoacrylic acid 50 45 45 45 2-hydroxyethyl methacrylate (mol%) 8 - 7 7 Ethylhexyl methacrylate (mol%) 7 7 7 7 Methyl methacrylate (mol%) - 18 - - Molecular weight 30,000 28,000 28,000 35,000 Viscosity (cP) 15,000 12,000 12,000 > 20,000 Examples 5 to 9 Preparation of Negative Photoresist Composition Dispersing Conductive Micropowder and Dissolving Alkali According to the composition and content shown in Table 2 below, photopolymerization 19 1280077 initiator, anti-foaming agent and leveling agent were added to Example 1. The acrylate copolymer to 4 was then stirred at room temperature for 2 hours. Then, a photopolymerizable monomer was added thereto and stirred at room temperature for 4 hours to provide the dispersible conductive fine powder and the alkali-soluble negative photoresist composition. The thus obtained photoresist composition was filtered through a 4 Å sieve to remove impurities. Table 2 Composition Example 5 Example 6 Example 7 Example 8 Example 9 Acrylate Copolymer Example 1 - - 60.1 51.1 - Example 2 - - - Drink 60.1 Example 3 - 68.0 - - - Example 4 71.7 - - - - Photopolymerization Starting agent 1.6 2.0 2.8 2.8 2.8 Photopolymerizable monomer 14.3 28.1 30.8 40.9 30.8 Anti-foaming agent 3.7 0.1 4.0 3.1 4.0 Leveling agent 2 0.1 2.0 2.0 2.0 Stabilizer other compound 10 Slurry composition f ° Mixing 65 Ag/q Ag powder, 3% by weight inorganic binder, 0.05% by weight stabilizer, and 31.95 wt% dispersible conductive micropowder and alkali soluble negative photoresist composition, using a planetary blend The device was premixed and uniformly dispersed using a crucible roller mill to provide a silver paste composition. f Examples 11 to 14 5 According to Ag powder, the silver paste composition is evaluated. 20 1280077 Table 3 Part Example 11 Example 12 Example 13 Example 14 Ag powder 63 67 71 73 Inorganic binder 2.95 2.95 2.95 2.95 Stabilizer 0.05 0.05 0.05 0.05 Light Resistive composition 34 30 26 24 Development properties are well patterned (micron) 50 50 50 50 Thickness after development 8 9 11 11 Thickness after sintering 4 5 6 7 Viscosity (cP) 10,000 13,000 14,000 20,000

The Ag powder used had an average particle size of 1.2 μm. A stone penite lead fusion is used as an inorganic binder and phosphorous acid is used as a stabilizer. The 5 photoresist composition comprised 68% of an acrylic copolymer, 28.1% of a photopolymerizable monomer, 2% of a photopolymerization initiator, and 1.9% of other additives.

A silver paste composition was prepared in the same manner as in Example 10 except that the content of the Ag powder was as defined in Examples 11 to 14 of Table 3. The results were evaluated based on the characteristics of the silver paste composition having a dependency on the Ag powder content, which has good developing properties and pseudoplastic viscosity properties. Similarly, the printed properties and pattern thickness after sintering are good. Examples 15 to 18 21 1280077 of the silver paste group were evaluated according to the stabilizer content. Table 4 Part Example 15 Example 16 Example 17 Example 18 Ag powder 67 67 67 67 Inorganic binder 2.95 2.95 2.95 2.95 Stabilizer 0 - - - 0.05 - - - - 0.3 - - - - 1 Photoresist composition 30 30 30 30 Good development properties Normal pattern formation 50 50 50 - Gelation gelation No or no Ag powder used has an average particle size of 1.2 μm . A lead borate lead fusion is used as the inorganic binder and phosphorous acid is used as a stabilizer. 5 The photoresist composition comprises 68% of an acrylic copolymer, 28.1% of a photopolymerizable monomer, 2% of a photopolymerization initiator, and 1.9% of other additives. The evaluation of the composition characteristics of the silver paste which is dependent on the stabilizer content shows that although slight or no stabilizer can adversely affect the storage stability of the composition, it is difficult to form a pattern by providing an excessive amount of stabilizer. 10 Examples 19 to 22 The characteristics of the silver paste composition were evaluated according to the type of stabilizer. 12 1280077 Table 5 Part Example 19 Example 20 Example 21 Example 22 Ag powder 67 67 67 67 Inorganic binder 2.95 2.95 2.95 2.95 Stabilizer phosphite 0.05 - - - Phosphoric acid - 0.05 - - Ascorbic acid - - 0.05 - Benzotriazole - - - 0.05 Photoresist composition 30 30 30 30 Good development properties Pattern formation 50 50 50 50 Gelation without or without

The Ag powder used had an average particle size of 1.2 μm. A lead borate lead fusion was used as the inorganic binder and the anti- 5 oxidizing agent listed in the above Table 5 was used as a stabilizer. The photoresist composition comprised 68% of an acrylic copolymer, 28.1% of a photopolymerizable monomer, 2% of a photopolymerization initiator, and 1.9% of other additives.

Regardless of the type of stabilizer, the silver paste composition has good characteristics. Examples 23 to 26 10 Changes in the amount of exposure to the silver paste were evaluated 23 1280077 Table 6 Part Example 23 Example 24 Example 25 Example 26 Ag powder 67 67 67 67 Inorganic binder 2.95 2.95 2.95 2.95 Stabilizer 0.05 0.05 0.05 0.05 Photoresist composition 30 30 30 30 Exposure (mJ) 300 0 - - - 400 - 0 - - 800 - Odd 0 - 1,000 - - - 0 Developmental properties are well patterned 50 50 50 50 Ag used The average particle size of the powder was 丨.2 μm. Boron ytterbium acid mis-melting is used as the inorganic binder and sub-packaging is used as the stabilizer. The 5 photoresist composition comprised 68% of an acrylic copolymer, 28.1% of a photopolymerizable monomer, 2% of a photopolymerization initiator, and 19% of other additives. The silver paste composition of the present invention has good development properties and pattern formation regardless of the difference in exposure amount. Example 27 10 Formation of microelectrode A silver paste composition according to the above examples was printed on the surface of the glass substrate using a screen printing machine containing a SUS 325 mesh mask. The printed sample was dried in a 9 Torr: convection oven for 2 minutes. The thus formed silver paste-coated thin (four) is exposed to - 15 light emitted from an exposure apparatus (which is provided with a button) to perform pattern formation at a wavelength of 365 nm, and using a ceramic developer at 3 Developed under the generation. The developed micropattern was sintered in an electric furnace by the following procedure: sintering was started at room temperature and maintained. The organic material was carbonized at 3 Torr for 3 minutes and sintered at 550 Torr for 30 minutes to form a microelectrode. The (four) composition of the filament-forming microelectrode according to the present invention can be applied to a lower sintering process t, and thus is suitable for PDp fabrication. Similarly, because of the high viscosity, the silver paste composition is suitable for the fine phase microelectrode formed by the screen printing ribs, and has a print-printing property. Further, since the surfactant and the organic solvent are not separately used, the silver paste composition is simply and economically produced and it does not pollute the environment. Brief Description of Drawing C] Brother Figure 1 is a scanning electron micrograph (sem) after developing a 50 micron pattern of a silver paste composition according to the present invention. The second figure is formed in the development according to this SEM cross section of the inventive silver paste composition after 5 〇 micron pattern; FIG. 3 is an SEM image after sintering a 5 〇 micron pattern of the silver paste composition according to the present invention; and FIG. 4 is formed The SEM cross section after the silver poly-grade 50 micron pattern according to the present invention was sintered. [The main component of the schema represents the table] (none)

25

Claims (1)

Scope of Patent Application: Patent No. 093103048 Patent Application Scope of Application Revision Amendment Date··February 95 1. A silver paste composition for forming a microelectrode comprising: 5 a) 60 to 80% by weight The eight-8 powder, wherein the Ag powder has an average particle size of 0.5 to 3 μm; b) 1 to 10% by weight of the inorganic binder, wherein the inorganic binder is one or more selected from the group consisting of: Lead borate lead fusion, rotten acid solubilized, B2O3 · Si〇2 · MO and B2O3 · Si〇2 · 10 M'2〇, where Μ is a divalent metal ion and Μ' is a monovalent metal ion; c 0.001 to 1% by weight of a stabilizer; and d) 15 to 35% by weight of a negative photoresist composition which is capable of dispersing a conductive fine powder and soluble in a base, wherein the negative photoresist composition comprises: a) 30 to 70% by weight of propylene 15 acid ester copolymer represented by the following formula 1: R3 ^4 + h2_tHch2 - rt COOR, C00R2 (1) wherein I can be hydrogen, phenyl, benzyl, nitro substituted benzene a phenyl group substituted with a halogen, a benzyl group substituted with a nitro group, a QSCw alkyl group or a hydroxyl group a QSQo alkane 20 group; R2 can be ethylhexyl, isobutyl, tert-butyl, octyl, 3-decyloxybutyl or methoxypropanediol hydrazine; R3 can be 26 1. (different) positive Replace page 1^, «..! W jpr-w^ut^»W is hydrogen or sulfhydryl; R4 may be hydrogen or fluorenyl; ~ is an integer from 8 to 40; n2 is 1 or 2; or the following formula 2 : + "丨计-I七R6 COOR2 (2) wherein R5 may be hydrogen or a carboxyl group; R6 may be a phenyl, carboxyl or -OCOCH3 group; R7 may be hydrogen or a -CH2COOH group; R2, R4, ~ and ^) as defined above; b) 10 to 40% by weight of a photopolymerizable monomer; c) 0.5 to 10% by weight of a photopolymerization initiator; d) 0.1 to 10% by weight of an antifoaming agent; And e) 0.1 to 10% by weight of a leveling agent; and the composition of the silver paste has a viscosity of 3,000 to 60,000 cP. 2. The silver paste composition of claim 1, wherein the inorganic binder has a glass transition temperature of 360 to 500 ° C and glass softening temperature of 400 to 550 ° C. 3. The silver paste composition of claim 1 wherein the stabilizer is one or more selected from the group consisting of: benzene Triazole, ascorbic blood 4. A silver paste composition according to claim 1, wherein the photopolymerization initiator is one or more selected from the group consisting of: 2, 4 -bistrichloroindolyl-6-p-nonyloxystyryl-s-three tillage, 2-p-nonyloxystyryl-4,6-bistrichloroindenyl-s-three tillage, 2 ,4-three gas thiol-6-three 27 Tillage, 2,4-trichloromethyl-4-mercaptonaphthyl-6-three-pill, diphenyl ketone, p-(diethylamino)diphenyl ketone, 2,2-dichloro-4 -phenoxyethyl benzene, 2,2'-diethoxyethyl benzene, 2,2'-dibutylphenoxy acetophenone, 2-hydroxy-2-mercaptopropyl benzene, p-three Butyl butyl trichloro ethane benzene, p-tertiary butyl dichloro 5 acetophenone, 4,4 '-ethylamino diphenyl ketone, thioxanthone, 2- thioxanthone, 2-methyl Thiophenone, 2-isobutylthioxanthone, 2-dodecylthioxanthone, 2,4-dimethylthioxanthone and 2,4-diethylthioxanthone-2,2' -Bis-2-chlorophenyl_4,5,4',5'-tetraphenyl-2'-1,2'-bisimidazole. 5. The silver paste composition of claim 1, wherein the photopolymerizable monomer is one or more selected from the group consisting of 1,4-butylene glycol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, diisoamyl dipropionate Dipentaerythritolkisacrylate, penic acid pentaerythritol diisopentyl alcohol 15 ester, diacrylate glycerol, trimethylolpropane trimethacrylate, Isoamyl tetrabutyl acrylate, pentaerythritol dimercaptoate, ditol tridecyl acrylate, bisphenol A diacrylate derivative, trimethylolpropane triacrylate and polyacrylic acid diiso Pentaerythritol ester. 6. The silver paste composition of claim 1, wherein the leveling agent is 20 or more selected from the group consisting of an anionic copolymer and an aralkyl-modified polymethylalkyloxane. And the anti-foaming agent is one or more selected from the group consisting of polyester-modified polymethylalkyl oxy-oxygen, poly- oxy-combustion, non-crushed substrate polymerization. Compound, modified urea solution, polyester modified dimethyl polyoxane 28 And a polyester modified dinonyl polyoxyalkylene copolymer. A microelectrode formed using a silver paste composition as claimed in any one of claims 1 to 6. 29