KR101314533B1 - A paste for electrode comprising Al - Google Patents

Abstract

The present invention relates to an electrode-forming paste containing aluminum, in particular, in the electrode-forming paste, i) 3 to 30 parts by weight of spherical aluminum powder having a particle diameter of 2 to 3 µm; Ii) A paste for forming an electrode, comprising a metal powder containing 70 to 97 parts by weight of a silver powder having a particle diameter of 0.1 to 0.7 µm.

The electrode forming paste of the present invention can significantly lower the production cost while maintaining the electrical resistance, adhesion, and pattern resolution as compared to forming electrodes with expensive silver powder in conventional electrode formation.

Electrode, paste, PDP, aluminum

Description

Paste for forming electrode containing aluminum {A paste for electrode comprising Al}

The present invention relates to an electrode-forming paste containing aluminum, and more particularly, it is possible to significantly lower the production cost while maintaining the electrical resistance, adhesion, and pattern resolution as compared with the formation of the electrode with expensive silver powder in conventional electrode formation. The present invention relates to an electrode forming paste and an electrode forming method using the same.

2. Description of the Related Art [0002] In recent years, as demand for large-sized, high-density, high-definition, and high reliability has increased in display devices, various pattern processing techniques have been developed. Research on the paste and research on how to reduce the production cost is actively being carried out.

Plasma display panels (hereinafter referred to as 'PDP') are used in various fields at present because they have a faster response speed and easier size than those of liquid crystal panels. Conventionally, a method of forming an electrode on such a PDP is, as described in Korean Patent Application No. 10-2003-62924, by applying an electrode forming paste containing silver powder on a substrate or using a dry film. A method of forming a pattern by attaching it on a substrate and then exposing, developing and firing is used.

However, since the paste cost used to form the PDP electrode pattern contains a large amount of expensive silver powder, there was a problem in that the formation of the electrode was expensive. To solve this problem, many companies have been conducting various studies. There is an urgent need for a method that can significantly reduce the electrode formation cost while satisfying the electrical resistance, adhesion to the substrate, and pattern resolution.

In order to solve the problems of the prior art as described above, the present invention provides an electrode forming paste capable of significantly lowering the production cost while maintaining the electrical resistance, adhesion, and pattern resolution compared to forming the electrode with expensive silver powder in forming the electrode. It aims to provide.

In addition, an object of the present invention is to provide an electrode forming method that can significantly reduce the production cost while maintaining the electrical resistance, adhesion, pattern resolution of the electrode without any additional equipment using the electrode forming paste.

In order to achieve the above object,

In paste for electrode formation,

Iii) 3 to 30 parts by weight of spherical aluminum powder having a particle diameter of 2 to 3 µm;

Ii) A paste for forming an electrode, comprising a metal powder containing 70 to 97 parts by weight of silver powder having a particle diameter of 0.1 to 0.7 탆.

The electrode forming paste is preferably for forming a PDP electrode,

a) 40 to 80 parts by weight of the metal powder;

b) 5 to 30 parts by weight of the organic binder;

c) 1 to 10 parts by weight of the photopolymerizable monomer;

d) 1 to 10 parts by weight of photoinitiator;

e) 1 to 10 parts by weight of the low melting glass frit; And

f) 0.1 to 5 parts by weight of the sintering aid;

.

In another aspect, the present invention provides a method for forming an electrode, characterized in that the electrode forming paste is placed on a substrate and baked.

Preferably, the electrode is a bus electrode or an address electrode of the PDP.

Hereinafter, the present invention will be described in detail.

MEANS TO SOLVE THE PROBLEM The present inventors satisfy | fill the property of the electrical resistance, adhesiveness, pattern resolution, etc. which are required for the electrode forming paste which are urgently requested by many companies, and the electrode forming paste which can significantly improve the production competitiveness by significantly lowering the unit price of paste. In the past, using only expensive silver powder as the metal powder for forming electrodes, when using silver powder and aluminum powder of specific size in a specific content range, the unit cost of the paste was satisfied while satisfying properties such as electrical resistance, adhesion, and pattern resolution. Significantly lowered to confirm that the production competitiveness can be greatly improved, the present invention was completed.

The electrode forming paste of the present invention comprises: i) 3 to 30 parts by weight of a spherical aluminum powder having a particle size of 2 to 3 μm and ii) a metal powder containing 70 to 97 parts by weight of a silver powder having a particle size of 0.1 to 0.7 μm. Characterized in that. Preferably, the electrode forming paste comprises a) 40 to 80 parts by weight of the metal powder; b) 5 to 30 parts by weight of the organic binder; c) 1 to 10 parts by weight of the photopolymerizable monomer; d) 1 to 10 parts by weight of photoinitiator; e) 1 to 10 parts by weight of the low melting glass frit; And f) 0.1 to 5 parts by weight of the sintering aid.

As for the said aluminum powder of the electrode formation paste of this invention, the thing of the spherical particle size of 2-3 micrometers is used essentially. Preferably, the aluminum powder has a particle diameter of 2.0 to 2.7 μm. When the particle diameter is less than 2 ㎛, stability and difficulty in manufacturing are rather large, which may cause difficulty in unit cost and stability of the paste. When the particle size exceeds 3 μm, it is difficult to form an electrode requiring a fine pattern. There may be a problem in resistance and adhesion to the substrate.

In the electrode forming paste of the present invention, the aluminum powder is preferably contained in 3 to 30 parts by weight of 100 parts by weight of the metal powder for forming the electrode. When the content of the aluminum powder is less than 3 parts by weight, the cost reduction effect of the paste is insignificant, and when it exceeds 30 parts by weight, the electrical resistance of the formed electrode may be too high or may be problematic in adhesion with the substrate. Preferably the content of the aluminum powder is 10 to 15 parts by weight.

In addition, the silver powder of the electrode-forming paste of the present invention is preferably used having a spherical particle diameter of 0.1 to 0.7 ㎛. If the thickness is less than 0.1 μm, the manufacturing cost of the paste increases, the fluidity of the prepared paste may deteriorate, and workability may decrease. If the thickness exceeds 0.7 μm, the electrical resistance of the electrode may increase. Preferably the particle size of the silver powder is more preferably 0.4 to 0.6 ㎛.

In the electrode forming paste of the present invention, the silver powder is preferably contained in 70 to 97 parts by weight of 100 parts by weight of the metal powder for electrode formation. When the content of the aluminum powder is less than 70 parts by weight, the electrical resistance of the formed electrode may be too high or there may be a problem in adhesion to the substrate. When the content of the aluminum powder exceeds 97 parts by weight, the cost reduction effect of the paste is weak.

In the electrode forming paste of the present invention, the metal powder containing the aluminum powder and the silver powder is preferably included in an amount of 40 to 80 parts by weight based on the total paste composition. It is good in both sex and electrode pattern developability.

B) The organic binder used in the electrode forming paste of the present invention serves to impart bonding and developability of the paste components before firing, and an organic binder used in the conventional PDP electrode forming paste may be used. An acrylate resin is preferable, and the acrylate resin may be prepared by polymerizing an unsaturated carboxylic acid monomer, an aromatic monomer, and an acrylic monomer.

The unsaturated carboxylic acid monomer acts to increase the elasticity of the polymer through hydrogen bonding in the polymer, and specifically, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, vinyl acetic acid, .

The unsaturated carboxylic acid monomer is preferably contained in 20 to 50% by weight in the total monomers used in the production of acrylate resin, when the content is in the above range, the elastic properties of the polymer, the prevention of gelation during polymerization, and the degree of polymerization control We can satisfy all.

The aromatic monomer has a function of forming a stable pattern with respect to adhesion to a substrate, and specifically includes aromatic monomers such as styrene, benzyl methacrylate, benzyl acrylate, phenyl acrylate, phenyl methacrylate, 2-nitrophenyl acrylate, Methacrylate, 2-nitrobenzyl methacrylate, 2-chlorophenyl acrylate, 4-chlorophenyl acrylate, 4-chlorophenyl methacrylate, 2-chlorophenyl methacrylate, or 4-chlorophenyl methacrylate.

The aromatic monomer is preferably included in 10 to 40% by weight, more preferably 15 to 25% by weight in the total monomer used in the production of the acrylate resin. When the content is within the above range, adhesion with the substrate, adhesion of the pattern, linearity of the pattern formed, stable pattern realization, and easy removal during the firing process can all be satisfied.

In addition to the unsaturated carboxylic acid monomer and the aromatic monomer, the acrylic monomer used in the production of the acrylate resin functions to control the glass transition temperature and polarity of the polymer.

The acrylic monomer may be selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-hydroxyoctyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) And the content thereof is preferably 20 to 60% by weight based on the total monomers used in the production of the acrylate resin in consideration of the glass transition temperature, heat resistance, and intimacy with the substrate.

The acrylate resin prepared by polymerizing such monomers may be prepared by polymerizing in an organic solvent such that the gelation of the unsaturated carboxylic acid monomer, the aromatic monomer, and the acrylic monomer is prevented and the appropriate volatility is controlled.

Examples of the solvent include propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether propionate, ethyl ether propionate, terpinol, propylene glycol monomethyl ether acetate, dimethylamino formaldehyde, and methyl ethyl. Ketone, butyl carbitol, butyl carbitol acetate, gamma butyrolactone, or ethyl lactate may be used alone or in combination of two or more thereof.

The acrylate resin obtained by polymerizing such monomers in the presence of a solvent preferably has a weight average molecular weight of 10,000 to 100,000, more preferably 20,000 to 50,000. Within the above range, developability is improved.

In the present invention, it is preferable that the organic binder is included in the electrode forming paste in an amount of 5 to 30 parts by weight, and within the above range, the organic binder is suitable for the formation of the microelectrode pattern, the workability is improved, and the pattern is entangled during firing. I never do that.

In addition, the c) photopolymerizable monomer used in the electrode forming paste of the present invention provides a photocurability to the paste and promotes developability, and a photopolymerizable monomer used in a conventional PDP electrode forming paste may be used. As a specific example, 2-hydroxyethyl (meth) acrylate, 2-hydroxyoctyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl acrylate, etc. may be used alone or in combination. Or polyester of polybasic acid, such as phthalic acid, itaconic acid, maleic acid succinic acid, and hydroxyethyl (meth) acrylate can be used.

The photopolymerizable monomer may be included in the paste in an amount of 1 to 10 parts by weight, and is suitable for forming a microelectrode pattern in the above range.

In addition, d) photoinitiator used in the electrode forming paste of the present invention is a component for initiating a photoreaction can be used as a photoinitiator used in conventional PDP electrode forming paste, as a specific example, 2,4-bistrichloromethyl-6 -p-methoxystyryl-s-triazine, 2-p-methoxystyryl-4,6-bistrichloromethyl-s-triazine, 2,4-trichloromethyl-6-triazine, 2 Triazine-based compounds such as 4-trichloromethyl-4-methylnaphthyl-6-triazine; Benzoin compounds such as benzophenone and p- (diethylamino) benzophenone; 2,2-dichloro-4-phenoxyacetophenone, 2,2-diethoxyacetophenone, 2,2-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyltrichloroacetophenone And the like; Examples of the xanthates such as xanthone, thioxanthone, 2-methylthioxanthone, 2-isobutylthioxanthone, 2-dodecylthioxanthone, 2,4-dimethylthioxanthone and 2,4- A tonic compound; Or 2,2-bis-2-chlorophenyl-4,5,4,5-tetraphenyl-2-1,2-bisimidazole, 2,2-bis (2,4,6-tricyanophenyl)- Imidazole compounds such as 4,4,5,5-tetraphenyl-1,2-bisimidazole and the like can be used.

The photopolymerization initiator is preferably included in 1 to 10 parts by weight of the paste of the present invention. If the content is less than 1 part by weight, the degree of curing is lowered, and the low sensitivity makes it difficult to implement a normal pattern shape and is not good for the straightness of the pattern. If it exceeds 10 parts by weight, problems with storage stability may occur. Due to the degree of curing, the resolution may be lowered, and there is a problem in that a residual film is easily generated in portions other than the formed pattern.

In addition, the e) low melting glass frit used in the electrode forming paste of the present invention serves to enhance the adhesion and plastic strength with the paper material, the glass frit having a softening point of 400 to 600 ℃ conventionally used for the PDP electrode forming paste This may be used and as a specific example, bismuth-based, lead-based, phosphorus-based, lithium-based may be used. It is preferable to use a particle diameter of 1 to 10 μm, and the low melting glass frit is preferably included in the paste of the present invention in an amount of 1 to 10 parts by weight. When it is in the said range, adhesiveness with a base material and favorable electrical resistance can be exhibited.

In addition, f) the sintering aid used in the electrode forming paste of the present invention serves to help sinter the paste component, and in particular, to facilitate the sintering of the aluminum powder included in the present invention. The sintering aid may be used as a sintering aid used in the conventional electrode forming paste, as a specific example, silver acetate and nitrocellulose may be used, in particular a sintering aid containing a silver component It is good to use. The sintering aid is preferably included in 0.1 to 5 parts by weight of the paste of the present invention. Within the above range, good plasticity and electrical resistance are exhibited.

In addition, the electrode forming paste of the present invention containing the above components may be used as the usual additives such as colorants, dyes, dispersants, anti-scratching agents, plasticizers, adhesion promoters, speed enhancers, surfactants, etc., which are conventional additives as necessary. By further including in the range of 0.01 to 10 parts by weight of the content can be improved performance according to the characteristics of the individual process, of course.

The electrode forming paste of the present invention may be obtained by blending the above-mentioned essential components and optional components in a predetermined ratio and uniformly dispersing them with a kneader such as a blender or a triaxial roll.

In another aspect, the present invention provides an electrode forming method characterized in that the electrode forming paste is placed on a substrate and baked, preferably, the electrode is a PDP bus electrode or an address electrode.

The electrode forming method, characterized in that the electrode forming paste of the present invention is placed on a substrate and fired, except that the electrode forming paste of the present invention is used, a known electrode forming method of forming an electrode using a paste may be applied. have. The substrate may be glass or film, and the method of placing the paste on the substrate may be applied by a bar coater or a blade coater, screen printing, offset printing, or dry film. After the paste is placed on the substrate, a fine pattern of electrodes may be formed on the final substrate through a series of electrode formation processes of drying, exposure, development and firing.

In particular, the electrode forming method of the present invention can significantly reduce the production cost while maintaining the electrical resistance, adhesion, and pattern resolution of the expensive paste used in the conventional electrode formation without additional equipment.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the scope of the present invention is not limited to the following examples.

[Example]

Example 1

44 parts by weight of a spherical aluminum powder having an average particle diameter of 2.6 µm, 312 parts by weight of a spherical silver powder having an average particle diameter of 0.4 µm, and methacrylic acid (MA): benzyl acrylate (BA) using propylene glycol monomethyl ether as a solvent. : 2-hydroxyethyl (meth) acrylate (2-HEMA): Methyl (meth) acrylate (MMA) = 30: 20: 10: 40 Acrylate resin prepared by polymerization at a weight ratio of 40 (weight average molecular weight 25,000) 91 parts by weight, 16 parts by weight of 2-hydroxyethyl acrylate as a photopolymerizable monomer, 14 parts by weight of benzophenone as a photoinitiator, 11 parts by weight of a low melting glass frit having a particle size of 3.36 µm and a softening point of 466 ° C., as a sintering aid 3 parts by weight of the plasticizer and 3 parts by weight of the surfactant were mixed with 1.3 parts by weight of silver acetate and the additives, and dispersed in a kneader to prepare an electrode forming paste.

Example 2

An electrode forming paste was manufactured in the same manner as in Example 1, except that 36 parts by weight of aluminum powder and 320 parts by weight of silver powder were used in Example 1.

Example 3

An electrode forming paste was prepared in the same manner as in Example 1, except that the particle size of the aluminum powder in Example 1 was 2.8 μm.

Example 4

An electrode forming paste was prepared in the same manner as in Example 1, except that the particle size of the silver powder was 0.5 μm in Example 1.

Comparative Example 1

An electrode forming paste was prepared in the same manner as in Example 1, except that silver powder having a particle size of 2 μm, which is generally used in a conventional PDP electrode paste, was used as a metal powder without using aluminum powder. .

Comparative Example 2

An electrode forming paste was manufactured in the same manner as in Example 1, except that 119 parts by weight of aluminum powder and 237 parts by weight of silver powder were used in Example 1.

Comparative Example 3

An electrode forming paste was prepared in the same manner as in Example 1, except that the particle size of the aluminum powder was 4 μm in Example 1.

Comparative Example 4

An electrode forming paste was prepared in the same manner as in Example 1, except that 1.5 μm of silver powder was used in Example 1.

Using the electrode forming paste prepared in Examples 1 to 4 and Comparative Examples 1 to 4, the electrical resistance, adhesion to the substrate, and pattern resolution were measured and shown in Table 1 below.

Experimental method was formed on the glass substrate for the electrode forming paste prepared in Examples 1 to 4 and Comparative Examples 1 to 4 by using a bar coater on a glass substrate, and then formed a front printing pattern at 10 ° C at 110 ° C in a drying furnace. After drying for 5 minutes, the dried test pieces were UV irradiated at 50, 100 and 200 mJ / cm ² , respectively, and then developed with 4 wt% Na ₂ CO ₃ aqueous solution and washed with pure water (DI water). The board | substrate with a pattern was heated up to 580 degreeC at 10 degree-C / min, it hold | maintained at 580 degreeC for 10 minutes, and it baked and manufactured the test piece. The electrical resistance of the prepared test piece was calculated through the film thickness and resistance value of the pattern, and the adhesion with the substrate was determined by peeling off the adhesive tape on the manufactured test piece, and whether or not there was peeling, the resolution was the minimum line of the prepared test piece. The width was measured.

Electrical resistance (Ω / cm) Adhesiveness Resolution (탆) Example 1 0.02 Good 20 Example 2 0.02 Good 20 Example 3 0.02 Good 20 Example 4 0.02 Good 20 Comparative Example 1 0.02 Good 20 Comparative Example 2 0.06 Bad 20 Comparative Example 3 0.07 Bad 25 Comparative Example 4 0.06 Good 20

As shown in Table 1, the electrode forming pastes of Examples 1 to 4 according to the present invention exhibited electrical resistance, adhesion and resolution with Comparative Example 1 using only silver powder having a particle diameter of 1.5 μm, thereby It was confirmed that the unit cost of the forming paste can be lowered by 20%. However, when the content of aluminum powder is too large (Comparative Example 2), or when the particle size of the aluminum powder is too large (Comparative Example 3), or when the particle size of the silver powder is too large (Comparative Example 4), the electrical resistance is too large or It was confirmed that the adhesion was inferior.

The electrode forming paste and the electrode forming method according to the present invention can significantly lower the production cost while maintaining the electrical resistance, adhesion, and pattern resolution compared to forming the electrode with expensive silver powder in forming the PDP electrode.

Claims (11)

In paste for electrode formation, a) 3 to 30% by weight of spherical aluminum powder having a particle diameter of 2 to 3 µm;    Ii) 40 to 80 parts by weight of a metal powder containing 70 to 97% by weight of a silver (Ag) powder having a particle diameter of 0.1 to 0.7 µm; b) 5 to 30 parts by weight of the organic binder; c) 1 to 10 parts by weight of the photopolymerizable monomer; d) 1 to 10 parts by weight of photoinitiator; e) 1 to 10 parts by weight of the low melting glass frit; And f) 0.1 to 5 parts by weight of the sintering aid; Electrode forming paste comprising a. The method of claim 1, The particle formation paste of the said aluminum powder is 2.4-2.7 micrometers, The electrode forming paste characterized by the above-mentioned. The method of claim 1, Particle diameter of the silver (Ag) powder is 0.3 to 0.6 ㎛, the electrode forming paste, characterized in that. delete The method of claim 1, 20 to 50 wt% of the unsaturated carboxylic acid; 10 to 40% by weight aromatic monomer; And 20 to 60% by weight of an acrylic monomer. The method of claim 1, The softening point (Ts) of the said low melting glass frit is 400-600 degreeC, The electrode formation paste characterized by the above-mentioned. The method of claim 1, The paste for forming an electrode, wherein the sintering aid is silver acetate. The method of claim 1, The electrode forming paste is a paste for forming a PDP electrode. The electrode forming method according to claim 1, wherein the electrode forming paste is placed on a substrate and baked. 10. The method of claim 9, And the electrode is a bus electrode or an address electrode of the PDP. The electrode formed by the electrode formation method of Claim 9.