KR20040030236A - Conductive Paste Composition, Transfer Film for Forming Electrode and Electrode for Plasma Display Panel - Google Patents

Abstract

PURPOSE: A conductive paste composition and a transfer film for electrode formation are provided to improve the electroconductivity and cohesiveness in electrode pattern, thereby being advantageously used in electrodes of plasma display panel (PDP). CONSTITUTION: The conductive paste composition comprises: (A) an electroconductive powder having the specific surface area of 1.5-5.0m2/g and comprising at least Ag powder; (B) a glass frit wherein the glass frit is a smokeless glass frit having a softening point of at least 400-600deg.C; and (C) a binding resin comprising at least (meth)acryl resin containing carboxyl groups. The transfer film for electrode formation comprises an electroconductive resin layer obtained from the electroconductive composition.

Description

Conductive paste composition, electrode for transfer film and electrode for plasma display panel {Conductive Paste Composition, Transfer Film for Forming Electrode and Electrode for Plasma Display Panel}

The present invention relates to a conductive paste composition, a transfer film for forming an electrode and an electrode for a plasma display panel, and more particularly, a conductive paste composition, a transfer film for forming an electrode, which can be used suitably for forming an electrode of a plasma display panel, and The present invention relates to an electrode for plasma display panel obtained using the same.

Plasma display panels (PDPs) are attracting attention among flat panel display technologies due to their ease of manufacturing process, wide viewing angle, and high display quality due to their self-luminous type. As a large display device, it is expected to become mainstream for the use of a wall-mounted television.

Color PDP can display a color by irradiating a fluorescent substance with the ultraviolet-ray generate | occur | produced by gas discharge. In general, in the color PDP, a phosphor region for red light emission, a phosphor region for green light emission, and a phosphor region for blue light emission are formed on a substrate, and the light emitting display cells of each color are uniformly mixed as a whole. Specifically, a partition wall including an insulating material called barrier rebar is provided on the surface of the substrate made of glass or the like, and a plurality of display cells are partitioned by the partition wall, and the inside of the display cell becomes a plasma working space. A phosphor portion is provided in the plasma working space and an electrode for applying a plasma to the phosphor portion is provided to form a PDP having each display cell as a display unit.

1 is a schematic diagram showing a cross-sectional shape of an AC PDP. In FIG. 1, 1 and 2 are glass substrates arrange | positioned opposingly, 3 is a partition, and a cell is partitioned by the glass substrate 1, the glass substrate 2, and the partition 3. 4 is a transparent electrode fixed to the glass substrate 1, 5 is a bus electrode formed on the transparent electrode for the purpose of lowering the resistance of the transparent electrode, 6 is an address electrode fixed to the glass substrate 2, 7 is maintained in the cell Phosphor, 8 is a dielectric layer formed on the surface of the glass substrate 1 to cover the transparent electrode 4 and the bus electrode 5, 9 is a dielectric layer formed on the surface of the glass substrate 2 to cover the address electrode 6, 10 is a protective film containing magnesium oxide, for example. In the direct current type PDP, a resistor is usually provided between the electrode terminal (anode terminal) and the electrode lead (anode lead). In addition, in order to improve the contrast of the PDP, a red, green or blue color filter or black matrix may be provided between the dielectric layer 8 and the protective film 10 or the like.

As a method of manufacturing an electrode pattern in such a PDP, (1) an etching method in which a metal thin film is formed by sputtering deposition or the like and a pattern of the metal thin film is formed by etching liquid after coating, exposure and development of a resist, (2) The screen printing method of screen-printing a non-photosensitive inorganic powder containing resin composition on a board | substrate, and baking this, (3) forming the film of the photosensitive inorganic powder containing resin composition on a board | substrate, and attaching a photomask to this film The photolithographic method etc. which leave a pattern on a board | substrate by developing after irradiating an ultraviolet-ray through and baking this are known.

However, the etching method has a problem such as the need for a large vacuum equipment and the delay in the throughput in the process.

In addition, the screen printing method has a problem in that the demand for positional accuracy of the pattern is very high due to the increase in size and precision of the panel, and thus it is not possible to cope with normal printing.

Further, when the pattern having a film thickness of 5 μm or more is formed by the photolithography method, there is a problem that the sensitivity of the inorganic powder-containing resin composition to the depth direction of the film is insufficient, and the pattern is easily peeled from the substrate interface during development. have.

Therefore, as a means of solving the problems seen in the above etching method, screen printing method and photolithography method, the present inventors form a laminated film of a resist film and an inorganic powder-containing resin layer on a support film, and onto the support film. The laminated film formed on the substrate was transferred onto a substrate, the resist film constituting the laminated film was exposed to light to form a latent image of the resist pattern, the resist film was developed to present the resist pattern, and the inorganic powder-containing resin layer was etched. A manufacturing method comprising the step of forming an electrode on the surface of the substrate by a method including a step of forming a pattern of an inorganic powder-containing resin layer corresponding to a resist pattern and firing the pattern (hereinafter, referred to as a "dry film Act, also referred to as "Law" (Japanese Patent Laid-Open No. 11-162339, Japanese Patent Laid-Open No. 11-2). See 83495).

However, although such a high-precision pattern can be formed easily by such a manufacturing method, there existed an inadequate aspect in electrode performance, such as electroconductivity.

The subject of this invention is providing the electrically conductive paste composition which can form the electrode pattern which has the outstanding electroconductivity and the favorable adhesiveness, the transfer film for electrode formation, and the electrode for PDP obtained using the same.

1 is a cross-sectional view illustrating a general PDP.

<Explanation of symbols for the main parts of the drawings>

1 glass substrate

2 glass substrates

3 bulkhead

4 transparent electrodes

5 bus electrode

6 address electrode

7 phosphor

8 Dielectric Layer

9 dielectric layer

10 Shield

The electrically conductive paste composition of this invention contains the electrically conductive powder (A) specific surface area of 1.5-5.0 m <2> / g, (B) glass frit, and (C) bonding resin.

Moreover, it is preferable that the electrically conductive paste composition of this invention contains at least Ag powder as (A) electroconductive powder. Moreover, it is preferable to contain the lead-free glass frit whose softening point is 400-600 degreeC at least as (B) glass frit. Moreover, it is preferable to contain at least a carboxyl group-containing (meth) acrylic resin as (C) bonding resin.

The transfer film for electrode formation of this invention contains the conductive resin layer obtained by apply | coating the electrically conductive paste composition of this invention, It is characterized by the above-mentioned.

The electrode for PDP of this invention is formed using the electrically conductive paste composition of this invention, and / or the electrode transfer film for formation of this invention.

<Embodiment of the Invention>

EMBODIMENT OF THE INVENTION Hereinafter, the electrically conductive paste composition of this invention, the transfer film for electrode formation, and the electrode for PDP are explained in full detail.

<Conductive Paste Composition>

The electrically conductive paste composition of this invention contains at least (A) electroconductive powder, (B) glass frit, and (C) bonding resin, and it is essential that the specific surface area of (A) electroconductive powder is 1.5-5.0 m <2> / g.

(A) conductive powder

The specific surface area of the electroconductive powder contained in the electrically conductive paste composition of this invention is 1.5-5.0 m <2> / g, Preferably it is 1.5-4.0 m <2> / g, More preferably, it is 2.0-3.5 m <2> / g.

When the specific surface area of electroconductive powder is less than 1.5 m <2> / g, the electroconductivity of the electrode pattern obtained using an electrically conductive paste composition is not enough. On the other hand, when the specific surface area of electroconductive powder exceeds 5.0 m <2> / g, aggregation of powder will arise easily in a conductive paste composition, and it will become difficult to obtain a stable dispersion state. Moreover, the adhesiveness with respect to the board | substrate of the electrode pattern obtained using an electrically conductive paste composition tends to be impaired.

In addition, the specific surface area here means the average value calculated | required by the BET method of the electroconductive powder contained in an electrically conductive paste composition.

Examples of the conductive powder in the conductive paste composition of the present invention include metals and alloys such as Ag, Au, Al, Cu, Ag-Pd alloys, and can be used alone or in combination of two or more thereof. It is especially preferable to use Ag which is relatively inexpensive, even if it bakes in air | atmosphere among these electroconductive powders, and the fall of electroconductivity does not occur.

The shape of the conductive powder is not particularly limited to granular, spherical or flake type, and may be used alone or in combination of two or more types of conductive powders. Moreover, the average particle diameter of the said electroconductive powder becomes like this. Preferably it is 0.1-5 micrometers, You may mix and use the electroconductive powder which has another particle diameter.

(B) glass frit

As the glass frit contained in the conductive paste composition of the present invention, a low melting glass frit is preferably used. Usually a glass frit with a softening point of 650 ° C. or lower is used, and preferably a glass frit with 400 to 600 ° C. is used. When the softening point of a glass frit is less than 400 degreeC, since melting of a glass frit starts before the bonding resin mentioned later in a baking process is removed and removed, there exists a possibility that an organic residue may remain in the pattern after baking. Moreover, when the softening point of a glass frit exceeds 600 degreeC, a glass frit does not melt enough in a baking process, and there exists a possibility that the adhesiveness of the pattern after baking may become inadequate.

As the composition of the glass frit, for example, (1) lead oxide, boron oxide, silicon oxide (PbO-B ₂ O ₃ -SiO _{2 type} ), (2) lead oxide, boron oxide, silicon oxide, aluminum oxide type ( PbO-B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ based), (3) zinc oxide, boron oxide, silicon oxide (ZnO-B ₂ O ₃ -SiO ₂ based), (4) zinc oxide, boron oxide , Silicon oxide, aluminum oxide type (ZnO-B ₂ O ₃ -SiO ₂ -Al ₂ O _{3 type} ), (5) lead oxide, zinc oxide, boron oxide, silicon oxide type (PbO-ZnO-B ₂ O _3- SiO ₂ based), (6) lead oxide, zinc oxide, boron oxide, silicon oxide, aluminum oxide based (PbO-ZnO-B ₂ O ₃ -SiO ₂ -Al ₂ O ₃ based), (7) bismuth oxide, oxide Boron, silicon oxide (Bi ₂ O ₃ -B ₂ O ₃ -SiO _{2 type} ), (8) bismuth oxide, boron oxide, silicon oxide, aluminum oxide type (Bi ₂ O ₃ -B ₂ O ₃ -SiO _2- Al ₂ O _{3 type} ), (9) bismuth oxide, zinc oxide, boron oxide, silicon oxide type (Bi ₂ O ₃ -ZnO-B ₂ O ₃ -SiO _{2 type} ), (10) bismuth oxide, zinc oxide, oxidation Boron, Silicon Oxide, Aluminum Oxide And the like _{(Bi 2 O 3 -ZnO-B} 2 O 3 -SiO 2 -Al 2 O 3 system). Among these glass frits, it is preferable to use the lead-free glass frit described in the above (3), (4), (7), (8), (9) and (10) as an environmental problem, and among these, the conductive paste composition It is particularly preferable to use a lead-free glass frit mainly containing bismuth oxide as described in (7), (8), (9) and (10) from the viewpoint of aging stability.

Moreover, the shape of the said glass frit is not specifically limited, The average particle diameter becomes like this. Preferably it is 0.1-10 micrometers, More preferably, it is 0.5-5 micrometers. When the average particle diameter of the glass frit is less than 0.1 µm, the specific surface area of the glass frit is large, so that aggregation of particles in the conductive paste composition tends to occur, making it difficult to obtain a stable dispersion state and at the same time changing the thickening of the conductive paste composition. It may occur. On the other hand, when the average particle diameter of glass frit is 10 micrometers or more, it becomes difficult to obtain a high precision electrode pattern.

The said glass frit can be used individually or in combination of 2 or more types of glass frits which have another glass frit composition, another softening point, another shape, and another average particle diameter.

The content of the glass frit in the conductive paste composition is preferably 1 to 30 parts by weight, particularly preferably 2 to 20 parts by weight based on 100 parts by weight of the conductive powder. When glass frit is less than 1 weight part, there exists a possibility that the adhesiveness to the board | substrate of the electrode obtained may become inadequate. Moreover, when it exceeds 30 weight part, there exists a possibility that the electroconductivity of the electrode obtained may fall, and the storage stability of an electrically conductive paste composition may fall, and a time-dependent change may occur.

(C) binding resin

Various resins can be used as the binder resin contained in the conductive paste composition of the present invention, but it is preferable to use a resin containing an alkali-soluble resin in a proportion of 30 to 100% by weight. Here, "alkali solubility" means the property which has solubility so that it may melt | dissolve by alkaline etching liquid and the target etching process may be performed.

As a specific example of these alkali-soluble resin, (meth) acrylic-type resin, hydroxy styrene resin, a novolak resin, polyester resin, etc. are mentioned, for example.

Among such alkali-soluble resins, carboxyl group-containing (meth) acrylic resins such as copolymers of the following monomers (a) and monomers (c), copolymers of monomers (a), monomers (b) and monomers (c) are particularly preferred. Can be mentioned.

Monomer (A): Carboxyl group-containing monomers

Acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid, mesaconic acid, cinnamic acid, succinic acid mono (2- (meth) acryloyloxyethyl), ω-carboxy-polycaprolactone mono (Meth) acrylates and the like.

Monomer (B): OH-containing monomers

Hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 3-hydroxypropyl (meth) acrylate; Phenolic hydroxyl group containing monomers, such as o-hydroxy styrene, m-hydroxy styrene, and p-hydroxy styrene.

Monomer (C): Other copolymerizable monomers

Methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, n-lauryl (meth) acrylate, benzyl (meth) acrylate, glycidyl (meth) acrylate, dicyclopentanyl (meth) (Meth) acrylic acid esters other than monomer (a), such as an acrylate; Aromatic vinyl monomers such as styrene and α-methylstyrene; Conjugated dienes such as butadiene and isoprene; Macromonomers which have a polymerizable unsaturated group, such as a (meth) acryloyl group, in one terminal of polymer chains, such as polystyrene, methyl poly (meth) acrylate, poly (meth) acrylate, and benzyl poly (meth) acrylate:

The copolymer of the monomer (A) and the monomer (C) or the copolymer of the monomer (A), the monomer (B) and the monomer (C) has alkali solubility by the presence of a copolymerization component derived from the monomer (A). do. Especially, the copolymer of a monomer (A), a monomer (B), and a monomer (C) is especially preferable from a viewpoint of the dispersion stability of (A) electroconductive powder and (B) glass frit, and the solubility to the alkali developing solution mentioned later. The content rate of the copolymerization component derived from the monomer (a) in this copolymer becomes like this. Preferably it is 5-60 mass%, Especially preferably, it is 10-40 mass%, and the content rate of the copolymerization component derived from a monomer (b) is Preferably it is 1-50 mass%, Especially preferably, it is 5-30 mass%.

The molecular weight of the alkali-soluble resin constituting the conductive paste composition is preferably 5,000 to 5,000,000, more preferably 10,000 to 300,000, in terms of weight average molecular weight (hereinafter referred to as "Mw") in terms of polystyrene by GPC.

In the electrically conductive paste composition of this invention, it is preferable that it is the ratio of 5-50 weight part with respect to 100 weight part of (A) electroconductive powder as a use ratio of (C) binder resin. When the content of the binder resin is less than 5 parts by weight, agglomeration of powder is likely to occur in the conductive paste composition, and it may be difficult to obtain a stable dispersion state, and the flexible film for forming an electrode formed by applying the conductive paste composition may be In some cases, the properties and the transferability may be significantly reduced. When the content of the binder resin exceeds 50 parts by weight, the shrinkage of the pattern tends to be large in the step of the firing treatment in the electrode forming step, and there is a fear that the deformation of the pattern occurs.

(D) solvent

The electrically conductive paste composition of this invention contains a solvent normally. As said solvent, (A) electroconductive powder, affinity with (B) glass frit, and the solubility of (C) bonding resin are favorable, an appropriate viscosity can be provided to an electrically conductive paste composition, and it can be easily evaporated and removed by drying. It is desirable to be able to.

Specific examples of such a solvent include ketones such as diethyl ketone, methyl butyl ketone, dipropyl ketone, and cyclohexanone; alcohols such as n-pentanol, 4-methyl-2-pentanol, cyclohexanol and diacetone alcohol; Ether alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether and propylene glycol monoethyl ether; Saturated aliphatic monocarboxylic acid alkyl esters such as acetic acid-n-butyl and amyl acetate; Lactic acid esters such as ethyl lactate and lactic acid-n-butyl; Ether-based esters such as methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, and ethyl-3-ethoxypropionate, and the like can be exemplified, and these can be used alone or in combination of two or more thereof. Can be used.

Although the content rate of a solvent in an electrically conductive paste composition can be suitably selected within the range from which favorable film formation property (flowability or plasticity) is obtained, it is normally 1-10,000 weight part with respect to 100 weight part of (A) electroconductive powder, Preferably Is 10 to 1,000 parts by weight.

In addition to the above components, the conductive paste composition may contain other inorganic powders, plasticizers, development accelerators, adhesion aids, storage stabilizers, antifoaming agents, antioxidants, ultraviolet absorbers, dispersants, crosslinking agents, photopolymerization initiators, photoacid generators, thermal polymerization initiators, thermal acid generators, and the like. Various additives of can be contained as an arbitrary component.

In particular, it is preferable to use a plasticizer for the conductive paste composition in order to maintain the flexibility and transferability of the transfer film for forming an electrode of the present invention. As the plasticizer used in the conductive paste composition, various compounds can be used, and dibutyl adipate, diisobutyl adipate, di-2-ethylhexyl adipate, di-2-ethylhexyl azelate, dibutyl sebacate and di Di (meth) acrylates of compounds such as butyl diglycol adipate, propylene glycol monolaurate, propylene glycol monooleate and di-2-ethylhexyl phthalate or alkylene glycols such as ethylene glycol and propylene glycol; Di (meth) acrylates of polyalkylene glycols such as polyethylene glycol and polypropylene glycol; Poly (meth) acrylates of trivalent or higher polyhydric alcohols such as glycerin, 1,2,4-butanetriol, trimethylolalkane, tetramethylolalkane, pentaerythritol, dipentaerythritol, or dicarboxyl thereof Acid denaturates; The (meth) acrylate compound which has one or more (meth) acryloyl groups in a molecule | numerator, such as poly (meth) acrylates of polyalkylene glycol adduct of a trivalent or more polyhydric alcohol, is used.

It is preferable to contain content of the plasticizer in an electrically conductive paste composition in the ratio of 0.5-30 weight part with respect to 100 weight part of (A) electroconductive powder, More preferably, it is 1-20 weight part.

Moreover, the electrically conductive paste composition of this invention may be a thing with photosensitivity, and in this case, a photosensitivity is provided by adding the radiation sensitive component which comprises the alkali-developed radiation sensitive resist composition mentioned later. When photosensitive property is provided to the conductive paste composition, an electrode pattern can be formed without using a resist composition.

The conductive paste composition uniformly dissolves the (C) bonding resin and the optional organic component as necessary and makes it a vehicle, followed by mixing with the (A) conductive powder, (B) glass frit and optionally the inorganic powder as necessary. And kneading using a kneading machine such as a roll kneader, a mixer, a homo mixer, a ball mill and a bead mill.

The conductive paste composition prepared as described above is a paste-like composition having fluidity suitable for application, and its viscosity is usually 100 to 100,00 cp, and preferably 500 to 10,000 cp.

<Transfer Film for Electrode Formation>

It is essential for the transfer film for electrode formation of this invention to contain the conductive resin layer obtained by apply | coating the electrically conductive paste composition of this invention.

The transfer film for electrode formation of this invention is comprised from the support layer and the transfer layer which has at least the electrically conductive resin layer obtained by apply | coating the electrically conductive paste composition of this invention, and is used for the formation process of the electrode by a dry film method Material.

It is preferable that the support film which comprises the transfer film for electrode formation of this invention is a resin film which has flexibility and heat resistance and solvent resistance. Since the support film has flexibility, the conductive paste composition of the present invention can be applied by a roll coater, a blade coater, a slit coater, or the like, and the conductive resin layer can be stored and supplied in a rolled state. Examples of the resin forming the support film include fluorine-containing resins such as polyethylene terephthalate, polyester, polyethylene, polypropylene, polystyrene, polyimide, polyvinyl alcohol, polyvinyl chloride, polyfluoroethylene, nylon, cellulose, and the like. Can be mentioned. The thickness of a support film is 20-100 micrometers, for example.

Moreover, it is preferable that the mold release process is given to the surface of the said support film. Thereby, the peeling operation of a support film can be easily performed in the transfer process to a board | substrate.

The conductive resin layer which comprises the transfer film for electrode formation of this invention can be formed by apply | coating the conductive paste composition of this invention mentioned above, drying a coating film, and removing a part or all of a solvent.

As a method of apply | coating an electrically conductive paste composition, it is preferable that the coating film with a large film thickness (for example, 1 micrometer or more) excellent in the uniformity of film thickness can be formed efficiently, Specifically, the coating method by a roll coater, The coating method by a blade coater, the coating method by a slit coater, the coating method by a curtain coater, the coating method by a wire coater, the coating method by a gravure coater, etc. are mentioned as a preferable thing.

Drying conditions of a coating film are about 0.5 to 30 minutes at 50-150 degreeC, and the residual ratio (content in a conductive resin layer) of a solvent after drying is 2 mass% or less normally.

The film thickness of the conductive resin layer formed as mentioned above is 1-100 micrometers normally, Preferably it is 3-50 micrometers, Especially preferably, it is 5-40 micrometers.

Moreover, a protective film can be provided in the transfer film for electrode formation of this invention in contact with the surface of a transfer layer. The protective film can use the same thing as a support film. Moreover, a mold release process is normally given to the surface of a protective film, and it is necessary that peeling strength of a protective film is smaller than peeling strength of a support film.

The transfer film for forming an electrode of the present invention may be one in which a resist layer is formed on a support film and a conductive resin layer is laminated. By transferring this laminated film onto the substrate, a laminated film having a resist layer formed on the conductive resin layer can be obtained.

Moreover, the transfer film for electrode formation of this invention,

(A-1) It is preferable that the conductive resin layer obtained by apply | coating the electrically conductive paste composition of this invention, and (A-2) the colored resin layer containing the inorganic powder which has a coloring pigment, and binding resin at least are laminated | stacked. It is preferable that the colored resin layer contains the above-mentioned conductive powder and glass frit as inorganic powder.

By using this laminated film, it is possible to collectively form a laminated electrode composed of a conductive resin layer and a colored resin layer, and also to form an electrode that is very suitable for a PDP bus electrode having excellent adhesion to a substrate, conductivity, and low external light reflection. .

In addition, in the transfer film for forming an electrode of the present invention, a resist layer is formed on a supporting film, and the conductive resin layer and the colored resin layer may be sequentially formed thereon. By transferring this laminated film to a substrate, a laminated film in which a conductive resin layer is formed on a colored resin layer and a resist layer is formed thereon can be obtained.

The colored resin layer and the resist layer can be formed in the same manner as the conductive resin layer, by applying the colored pigment-containing paste composition and the resist composition described later, drying the coating film, and removing part or all of the solvent.

The film thickness of the colored resin layer thus formed is usually 1 to 20 µm, preferably 3 to 15 µm, particularly preferably 5 to 10 µm.

Moreover, the film thickness of a resist layer is 1-20 micrometers normally, Preferably it is 3-15 micrometers, Especially preferably, it is 5-10 micrometers.

Color Pigment-containing Paste Composition

The colored pigment containing paste composition used for forming a colored resin layer contains the inorganic powder and binder resin which have a colored pigment at least.

The coloring pigment contained in a coloring pigment containing paste composition is added in order to prevent the external light reflection of the electrode obtained, for example, metals, such as Co, Cr, Cu, Fe, Mn, Ni, Ti, Zn, and its oxide, a composite Inorganic powders, such as an oxide, a carbide, a nitride, a sulfide, a silicide, a boride, or carbon black, graphite, are mentioned, and can be used individually or in mixture of 2 or more types. Preferred colored pigments include metal powders, metal oxide powders and composite oxide powders selected from the group of Co, Cr, Cu, Fe, Mn, Ni and Ti (for example, Ni powder, Co ₃ O ₄ powder, Fe ₃ O _4). Powder, Cu-Cr composite oxide powder, Cu-Fe-Mn composite oxide powder, Cu-Cr-Mn composite oxide powder, Co-Fe-Mn composite oxide powder, and the like. By using such a colored pigment, colored pigment containing paste compositions, such as black and gray, are obtained, for example.

The average particle diameter of the said colored pigment becomes like this. Preferably it is 1 micrometer or less, More preferably, it is 0.01-0.5 micrometer. When the inorganic powder containing resin composition whose average particle diameter of a colored pigment exceeds 1 micrometer is used, it is difficult to obtain the electrode which has sufficient external light reflection prevention effect. When the average particle diameter of a colored pigment is less than 0.01 micrometer, since the specific surface area of a colored pigment becomes large, aggregation of powder will occur easily in a colored pigment containing paste composition, and it will become difficult to obtain a stable dispersion state.

In the said coloring pigment containing paste composition, what is necessary is just to contain a coloring pigment as an inorganic powder, but it is preferable that an electroconductive powder and a glass frit are contained. The content ratio of electroconductive powder and colored pigment is the ratio whose value of electroconductive powder: colored pigment is 75: 25-25: 75 preferably. By using the coloring pigment containing paste composition containing electroconductive powder and a coloring pigment in the said content ratio, the bus electrode for PDP which has sufficient external light reflection prevention effect, and has electroconductivity which functions as an electrode can be formed. Moreover, the content rate of glass frit is 50 mass% or less with respect to all the inorganic powders used for a coloring pigment containing paste composition, Preferably it is 1-30 mass%.

Examples of the conductive powder in the colored pigment-containing paste composition include metals and alloys such as Ag, Au, Al, Cu, and Ag-Pd alloys, and can be used alone or in combination of two or more thereof. It is especially preferable to use Ag which is comparatively inexpensive, even if it bakes in air | atmosphere among these electroconductive powders, and electroconductivity does not fall.

The shape of the said electroconductive powder is not specifically limited, such as a granular form, a spherical form, and a flake type, It can use individually or in mixture of 2 or more types of shape. Moreover, the average particle diameter of the said electroconductive powder becomes like this. Preferably it is 0.1-5 micrometers, The electroconductive powder which has another particle diameter can be mixed and used.

As the glass frit, which is preferably contained in the colored pigment-containing paste composition, the same glass frit as the conductive paste composition of the present invention is used.

As a binder resin contained in the said colored pigment containing paste composition, the binder resin similar to the electrically conductive paste composition of this invention is mentioned.

In addition, the colored pigment-containing paste composition may contain a solvent and inorganic powders other than those described above, plasticizers, development accelerators, adhesion aids, storage stabilizers, antifoaming agents, antioxidants, ultraviolet absorbers, dispersants, crosslinking agents, and photopolymerization initiators in the same manner as the conductive paste composition of the present invention. Various additives, such as a photoacid generator, a thermal polymerization initiator, and a thermal acid generator, can be contained as an arbitrary component.

A colored pigment containing paste composition can be manufactured similarly to the electrically conductive paste composition of this invention.

The colored pigment-containing paste composition prepared as described above is a paste-like composition having fluidity suitable for application, and its viscosity is usually 100 to 100,00 cp, and preferably 500 to 10,000 cp.

Resist composition

As a resist composition used for forming a resist layer, although an alkali developing radiation sensitive resist composition, an organic solvent developing radiation sensitive resist composition, an aqueous developing radiation sensitive resist composition, etc. can be illustrated, Preferably it is an alkali developing type A radiation sensitive resist composition is used. "Radiation" as used in the present invention includes visible rays, ultraviolet rays, far ultraviolet rays, electron beams, X rays and the like.

An alkali developing radiation sensitive resist composition contains alkali-soluble resin and a radiation sensitive component as essential components. As alkali-soluble resin which comprises an alkali image development radiation sensitive resist composition, alkali-soluble resin illustrated as what comprises an inorganic powder containing resin composition is mentioned.

As a radiation sensitive component which comprises an alkali-developing radiation sensitive resist composition, it is (a) combination of a reactive monomer and a photoinitiator, (b) melamine resin and the photoacid generator which forms an acid by irradiation, for example. A combination etc. can be illustrated as a preferable thing, and the combination of a (meth) acrylate compound and a photoinitiator is especially preferable among the combination of said (a).

As a specific example of the (meth) acrylate compound which comprises a radiation sensitive component, Di (meth) acrylates of alkylene glycol, such as ethylene glycol and propylene glycol; Di (meth) acrylates of polyalkylene glycols such as polyethylene glycol and polypropylene glycol; Di (meth) acrylates of both terminal hydroxylated polymers such as both terminal hydroxypolybutadiene, both terminal hydroxypolyisoprene and both terminal hydroxypolycaprolactone; Poly (meth) acrylates of trivalent or higher polyhydric alcohols such as glycerin, 1,2,4-butanetriol, trimethylolalkane, tetramethylolalkane, dipentaerythritol, etc .; Poly (meth) acrylates of polyalkylene glycol adducts of trivalent or higher polyhydric alcohols; Poly (meth) acrylates of cyclic polyols such as 1,4-cyclohexanediol and 1,4-benzenediols; Oligos, such as polyester (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, alkyd resin (meth) acrylate, silicone resin (meth) acrylate, and spiran resin (meth) acrylate ( And meth) acrylates. These may be used alone or in combination of two or more thereof.

Specific examples of the photopolymerization initiator constituting the radiation sensitive component include benzyl, benzoin, benzophenone, camphorquinone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 1-hydroxycyclohexylphenyl ketone , 2,2-dimethoxy-2-phenylacetophenone, 2-methyl- [4 '-(methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1 Carbonyl compounds such as-(4-morpholinophenyl) -butan-1-one; Azo compounds or azide compounds such as azoisobutyronitrile and 4-azide benzaldehyde; Organic sulfur compounds such as mercaptan disulfide; Organic peroxides such as benzoyl peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide and paramethane hydroperoxide; 1,3-bis (trichloromethyl) -5- (2'-chlorophenyl) -1,3,5-triazine, 2- [2- (2-furanyl) ethylenyl] -4,6-bis Trihalo methanes such as (trichloromethyl) -1,3,5-triazine; Imidazole dimers such as 2,2'-bis (2-chlorophenyl) 4,5,4 ', 5'-tetraphenyl1,2'-biimidazole, and the like. The above can be used in combination.

The content rate of the radiation sensitive component in such an alkali developing radiation sensitive resist composition is 1-300 weight part normally per 100 weight part of alkali-soluble resin, Preferably it is 10-200 weight part.

Moreover, in alkali developing type radiation sensitive resist composition, in order to provide favorable film formation property, an organic solvent is contained suitably. As such an organic solvent, the solvent illustrated as what comprises an inorganic powder containing resin composition is mentioned.

In addition to the above components, the resist composition may contain various additives, such as a development accelerator, an adhesion aid, a storage stabilizer, an antifoaming agent, an antioxidant, an ultraviolet absorber, and a leveling agent, as optional components.

A resist composition can be manufactured by dissolving the said alkali-soluble resin, a radiation sensitive component, and the said arbitrary component uniformly as needed.

The resist composition prepared as described above is a paste-like composition having fluidity suitable for application, and its viscosity is usually 10 to 10,000 cp, and preferably 100 to 1,000 cp.

<Formation of Electrode>

In the formation method of the electrode for PDP of this invention, it is preferable to use the transfer film for electrode formation of this invention, [1] the conductive resin layer transfer process, [2] the resist film formation process, [3] the resist film exposure process , [4] a resist film development step, a [5] conductive resin layer etching step, and a [6] pattern firing step. [1] In the transfer step of the conductive resin layer, a laminated film of the conductive resin layer and the colored resin layer is preferably used.

[1] transfer process of conductive resin layer

The conductive resin layer is formed by transferring the conductive resin layer constituting the transfer film onto the substrate using the transfer film for forming an electrode of the present invention. At this time, it is preferable to use the transfer film which has a conductive resin layer on a support film, and has a colored resin layer on this conductive resin layer, and the laminated film of a colored resin layer and a conductive resin layer is transferred.

An example of the transfer process is as follows. After peeling the protective film of the transfer film for electrode formation used as needed, the transfer film is superimposed on the board | substrate so that the surface of an electroconductive resin layer (in the case of a laminated | multilayer film) may contact, and this transfer film is heated. After thermocompression bonding with a roller or the like, the supporting film is peeled off from the conductive resin layer. As a result, the conductive resin layer is transferred onto the substrate and brought into close contact with the substrate. Moreover, in the case of a laminated film, a colored resin layer is formed on a board | substrate, a conductive resin layer is formed on it, and it is in the state in which it adhered.

Here, transfer conditions indicate that the surface temperature of the heating roller is 20 to 140 ° C., the roll pressure by the heating roller is 1 to 5 kg / cm 2, and the moving speed of the heating roller is 0.1 to 10.O m / min. Can be. In addition, the substrate may be preheated, and the preheating temperature may be, for example, 40 to 100 ° C.

[2] steps of forming resist films

In this step, a resist film is formed on the surface of the conductive resin layer.

A resist film can be formed by apply | coating the resist composition mentioned above by various methods, such as the screen printing method, the roll coating method, the rotation coating method, the flexible coating method, and then drying a coating film.

The resist film formed on the support film may also be formed by transferring onto the surface of the conductive resin layer, and as described above, the transfer film having the laminated film of the resist layer and the conductive resin layer, or the resist layer, the conductive resin layer and the colored resin layer. Batch transfer can be performed using the transfer film which has a laminated film of this. According to such a formation method, a process can be simplified and the film thickness uniformity of the electrode formed can be aimed at.

[3] exposure steps of resist films

In this step, the surface of the resist film is selectively irradiated (exposed) with radiation such as ultraviolet rays through an exposure mask to form a latent image of the resist pattern.

Here, the irradiation apparatus is not particularly limited, such as an ultraviolet irradiation apparatus used in the photolithography method, an exposure apparatus used when manufacturing a semiconductor and a liquid crystal display device.

[4] processes for developing resist films

In this step, the exposed resist film is developed to present the resist pattern (latent image).

The developer used in the development process of the resist film can be appropriately selected depending on the kind of the resist film (resist composition). Specifically, an alkaline developer can be used for a resist film made of an alkali developing radiation-sensitive resist composition.

As an active ingredient of alkaline developing solution, for example, lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium hydrogen phosphate, diammonium hydrogen phosphate, dipotassium hydrogen phosphate, dibasic sodium hydrogen phosphate, ammonium dihydrogen phosphate, potassium dihydrogen phosphate, dihydrogen phosphate Inorganic alkaline compounds such as sodium, lithium silicate, sodium silicate, potassium silicate, lithium carbonate, sodium carbonate, potassium carbonate, lithium borate, sodium borate, potassium borate and ammonia; Tetramethylammonium Hydroxide, Trimethylhydroxyethylammonium Hydroxide, Monomethylamine, Dimethylamine, Trimethylamine, Monoethylamine, Diethylamine, Triethylamine, Monoisopropylamine, Diisopropylamine, Ethanolamine Organic alkaline compounds, such as these, etc. are mentioned.

The alkaline developer used in the development step of the resist film can be produced by dissolving one or two or more kinds of the alkaline compounds in water or the like. In the alkaline developer, the concentration of the alkaline compound is usually 0.001 to 10% by weight, preferably 0.01 to 5% by weight. In addition, after the development process by alkaline developing solution is performed, the water washing process is performed normally.

Here, the development treatment conditions include the type, composition, and concentration of the developing solution, the developing time, the developing temperature, the developing method (for example, the dipping method, the shaking method, the shower method, the spray method, the paddle method), the developing apparatus, etc. Can be selected appropriately.

By this developing step, a resist pattern (pattern corresponding to the mask for exposure) formed of the resist remaining portion and the resist removing portion is formed.

This resist pattern acts as an etching mask in the next step (etching step), and the constituent material of the resist remaining portion needs to have a smaller dissolution rate in the etching solution than the constituent material of the conductive resin layer or the colored resin layer.

[5] etching steps for conductive resin layers

In this step, the conductive resin layer (and the colored resin layer) is etched to form a pattern of the conductive resin layer (and the colored resin layer) corresponding to the resist pattern.

That is, the part corresponding to the resist removal part of a resist pattern among a conductive resin layer melt | dissolves in an etching liquid, and is selectively removed. Then, if the etching process is continued, the surface of the substrate is exposed at the portion corresponding to the resist removing portion in the conductive resin layer (and the colored resin layer).

It is preferable that the etching liquid used at the etching process of a conductive resin layer is an alkaline solution. Thereby, alkali-soluble resin contained in a conductive resin layer (and colored resin layer) can be easily dissolved and removed.

In addition, since the inorganic powder contained in the conductive resin layer (and the colored resin layer) is uniformly dispersed by the alkali-soluble resin, the inorganic powder is also removed at the same time by dissolving and washing the alkali-soluble resin as the binder in an alkaline solution.

Here, as an alkaline solution used as an etching solution, the solution of the same composition as a developing solution is more preferable.

In the case where the etching solution is the same solution as the alkaline developer used in the developing step, the developing step and the etching step can be continuously performed, and the process can be simplified.

In addition, after the etching process by alkaline solution is performed, the water washing process is performed normally. Moreover, the process of rubbing off the unnecessary part which remain | survives in the conductive resin layer (and colored resin layer) pattern side surface and a board | substrate exposed part after an etching process can be included as needed.

Here, the type, composition, and concentration of the etching solution, the treatment time, the treatment temperature, the treatment method (for example, the dipping method, the rocking method, the shower method, the spray method, the paddle method), and the treatment device can be appropriately selected.

In addition, even if some or all of the resist remaining portion remains after the etching treatment, the resist remaining portion is removed in the next firing step.

[6] firing processes of patterns

In this step, the pattern of the conductive resin layer (and the colored resin layer) is baked to form an electrode. Thereby, the electrode in which the organic substance in a resin layer remainder is lost, and the pattern (lamination pattern in the case of a laminated film) is formed in the surface of a board | substrate can be obtained.

Here, the temperature of the firing treatment should be a temperature at which the organic material in the resin layer remaining portion disappears, and is usually 400 to 600 ° C. in the air. Moreover, baking time is 10 to 90 minutes normally.

<Example>

Hereinafter, although the Example of this invention is described, this invention is not limited by these. In addition, "part" shows a "weight part" below.

In addition, Mw is the weight average molecular weight of polystyrene conversion measured by the gel permeation chromatography (GPC) (brand name HLC-802A) by Toso Corporation.

<Example 1>

(1) Preparation of Conductive Paste Composition:

(A) 100 parts of Ag powder having a specific surface area of 1.8 m 2 / g as the conductive powder, and (B) Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ based glass frit having an average particle diameter of 3 μm as the glass frit (negative, softening point of 520 ° C.) 10 parts, (C) 2-ethylhexyl methacrylate / methacrylic acid 3-hydroxypropyl / methacrylic acid / mono succinate (2-methacryloyloxyethyl) = 60/20/20 / 20 parts by mass of 20 (mass%) copolymer (Mw = 50,000), 1 part of oleic acid as other optional components, 10 parts of di-2-ethylhexyl azelate, and 100 parts of propylene glycol monomethyl ether as a solvent, followed by A conductive paste composition was prepared by filtering into a mesh (500 mesh, 25 μm diameter).

(2) Preparation of alkali developable radiation sensitive resist composition:

Benzyl methacrylate / methacrylic acid = 75/25 (wt%) copolymer (Mw = 30,000) as alkali-soluble resin, 40 parts of tripropylene glycol diacrylates as a polyfunctional monomer (radiation sensitive component), photopolymerization After kneading 5 parts of 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one as an initiator (radiation sensitive component) and 100 parts of propylene glycol monomethyl ether acetate as a solvent, An alkali developing radiation sensitive resist composition (hereinafter referred to as a "resist composition") was prepared by filtration with a cartridge filter (2 µm diameter).

(3) Preparation of the transfer film:

The transfer film for electrode formation of this invention by which the laminated | multilayer film which laminates a resist film and an electroconductive resin layer in this order by the operation of following (a) and (b) is formed on a support film was manufactured.

(A) The resist composition prepared in (2) was applied onto a support film made of a PET film having a film thickness of 38 μm using a blade coater, and the coating film was dried at 100 ° C. for 3 minutes to remove the solvent to remove the solvent. A resist film was formed on the support film.

(B) The conductive paste composition prepared in (1) was applied onto the resist film prepared in (a) using a blade coater, and the coating film was dried at 100 ° C. for 5 minutes to remove the solvent, and the conductive water having a thickness of 25 μm. The base layer was formed on a resist film, and the transfer film for electrode formation which produced the laminated film which has a resist film and a conductive resin layer is formed on a support film.

(4) Transfer process of the laminated film:

The transfer film was overlaid so that the surface of the electroconductive resin layer of the electrode formation transfer film manufactured by (3) may contact the surface of a glass substrate, and this transfer film was thermocompression-bonded to the heating roller. In the crimping conditions, the surface temperature of the heating roller was 100 ° C, the roll pressure was 2.5 kg / cm, and the moving speed of the heating roller was 0.5 m / min. Thereby, the transfer film was transferred to the surface of the glass substrate, and it was in the state which contacted.

(5) Exposure process and development process of resist film:

I-line (wavelength 365) by an ultra-high pressure mercury lamp through a mask for exposure (the stripe pattern of 100 micrometers width and each pattern of 5 cm square) on a support film with respect to the resist film in the laminated film formed on the glass substrate in said (4). nm ultraviolet ray) was irradiated with 400 mJ / cm 2. The support film on the resist film was peeled off, and the development process of the resist film by the shower method which made 0.5 mass% aqueous sodium carbonate aqueous solution (30 degreeC) as a developing solution for the exposed resist film was then performed for 30 second.

As a result, the uncured resist not irradiated with ultraviolet rays was removed to form a resist pattern.

(6) Etching Process of Conductive Resin Layer:

Subsequently to the said process, the etching process of the electrically conductive resin layer by the shower method which makes 0.5 mass% sodium carbonate aqueous solution (30 degreeC) an etching liquid was performed for 60 second.

Subsequently, washing with water and drying treatment with ultrapure water were performed. Thereby, the pattern comprised by the conductive resin layer remainder and the conductive resin layer removal part was formed.

(7) firing process of the pattern:

The glass substrate in which the pattern of the conductive resin layer was formed was calcined at 590 ° C. for 30 minutes in an air atmosphere in the firing furnace. As a result, an electrode pattern having a thickness of 8 μm was formed on the surface of the glass substrate.

(8) Conductivity evaluation of the electrode pattern:

When the resistivity of the obtained electrode pattern (each pattern of 5 cm square) was measured by the four probe method, it was 2.9 microohm * cm and the outstanding electroconductivity of less than 3.0 microohm * cm was shown.

(9) Evaluation of adhesiveness of the electrode pattern:

The cellophane adhesive tape prescribed | regulated to JIS Z1522 was stuck on the obtained electrode pattern (stripe pattern of 100 micrometers width), and adhesiveness evaluation by the tape method based on JISK5400 was performed. As a result, peeling was not confirmed by the electrode pattern, and showed favorable adhesiveness.

<Examples 2 to 4>

In Example 1, except that the Ag particles having a specific surface area shown in Table 1 below were used as the (A) conductive powder, the preparation of the conductive paste composition, the preparation of the transfer film for forming an electrode, and the electrode pattern were carried out in the same manner as in Example 1. Formation and evaluation of the electrode pattern were performed.

Table 1 shows the evaluation results of the electrode patterns.

Example 5

In Example 2, (1) manufacture of the electrically conductive paste composition, (2) alkali developing type radiation sensitive resist composition was performed, and the following coloring pigment containing paste composition was produced as (1 ').

Preparation of (1 ') Color Pigment-Containing Paste Composition:

60 parts of Ag powder having an average particle diameter of 1 µm as the conductive powder, 40 parts of Cu-Fe-Mn composite oxide powder having an average particle diameter of 0.6 µm as the coloring pigment, and a Bi ₂ O ₃ -B ₂ O ₃ -having a mean particle diameter of 3 µm as the glass frit. 10 parts of SiO ₂ -based glass frit (atypical, softening point 520 ° C.), (C) 2-ethylhexyl methacrylate / methacrylic acid 3-hydroxypropyl / methacrylic acid / monosuccinate mono (2-methacrylo) as a binder resin Iloxyethyl) = 60/20/20/20 (mass%) copolymer (Mw = 50,000) 20 parts, 1 part of oleic acid as other optional components, 10 parts of di-2-ethylhexyl azelate and propylene glycol mono as solvent A colored pigment-containing paste composition was prepared by kneading 100 parts of methyl ether with a bead mill and then filtering through a stainless mesh (500 mesh, 25 μm diameter).

In Example 2, in the production of the transfer film (3), after the transfer film was produced in the same manner as in Example 2,

(C) On the electroconductive resin layer of the transfer film manufactured in (B) of Example 2, the coloring pigment containing paste composition manufactured by (1 ') was apply | coated using a blade coater, and a coating film was carried out at 100 degreeC for 5 minutes. The solvent is removed by drying, a 5 탆 thick conductive resin layer is formed on the resist film, and a laminated film formed by laminating a resist film, a conductive resin layer and a colored pigment-containing resin layer in this order is formed on the supporting film. The transfer film for electrode formation of this invention formed was produced, and it carried out similarly to Example 2, and formed the electrode pattern and evaluated the electrode pattern. Table 1 shows the evaluation results of the electrode patterns.

<Comparative Examples 1 to 3>

In Example 1, except having used Ag particle of the specific surface area shown in Table 1 as (A) electroconductive powder, it carried out similarly to Example 1, manufacture of a conductive paste composition, manufacture of the transfer film for electrode formation, formation of an electrode pattern. And electrode patterns were evaluated.

Table 1 shows the evaluation results of the electrode patterns.

<Comparative Example 4>

In Example 5, production of the conductive paste composition, production of the transfer film for forming an electrode, and formation of the electrode pattern were performed in the same manner as in Example 5, except that Ag particles having a specific surface area shown in Table 1 were used as the (A) conductive powder. And electrode patterns were evaluated. Table 1 shows the evaluation results of the electrode patterns.

Adhesion evaluation: ○ no peeling, × has peeling

Type of electrode: single layer single electrode, few stacked electrodes

According to the electrically conductive paste composition of this invention and the transfer film for electrode formation, the electrode pattern which has the outstanding electroconductivity and has favorable adhesiveness can be formed. The electrically conductive paste composition of this invention and the transfer film for electrode formation can be used suitably for electrode pattern formation of a plasma display panel.

Claims (7)

A conductive paste composition comprising (A) a conductive powder having a specific surface area of 1.5 to 5.0 m 2 / g, (B) glass frit, and (C) bonding resin. The conductive paste composition according to claim 1, wherein at least Ag powder is contained as the conductive powder (A). The electrically conductive paste composition of Claim 1 containing the lead-free glass frit whose softening point is 400-600 degreeC at least as a glass frit. The conductive paste composition according to claim 1, wherein at least a carboxyl group-containing (meth) acrylic resin is contained as the (C) bonding resin. The electroconductive resin layer obtained from the electrically conductive paste composition of Claims 1-4 is contained, The transfer film for electrode formation characterized by the above-mentioned. It is formed using the electrically conductive paste composition of Claims 1-4, The electrode for plasma display panels characterized by the above-mentioned. It is formed using the transfer film for electrode formation of Claim 5, The electrode for plasma display panels characterized by the above-mentioned.