JP2009300789A - Photosensitive composition, patterning method, and method of manufacturing electrode for flat panel display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition for forming an electrode pattern of high definition by forming a photosensitive resin layer causing no curvature at both ends of a pattern after baking while having high smoothness, and to provide a patterning method for forming the electrode pattern of high definition. <P>SOLUTION: The photosensitive composition contains (A) conductive particles, (B) glass particles, (C) a polymer containing (c1) a (meth)acrylate alkyl oxy-alkyl ester constitutional unit and (c2) a constitutional unit containing a carboxyl group, (D) a photopolymerizable monomer and (E) a photopolymerization initiator. The patterning method uses this photosensitive composition. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a photosensitive composition, a pattern forming method, and a method for producing an electrode for a flat panel display. More specifically, in the manufacture of a display panel such as a flat panel display or a circuit board having a fine circuit pattern used for advanced mounting materials for electronic components, it is preferably used when forming a highly accurate pattern. The present invention relates to a photosensitive composition, a pattern forming method using the same, and a method for producing a flat panel display member by the pattern forming method.

  In recent years, there is an increasing demand for higher density and higher definition for pattern processing in circuit boards and display panels. Among such display panels that have been increasing in demand, particularly flat panel displays (hereinafter referred to as “FPD”) such as plasma display panels (hereinafter also referred to as “PDP”) and field emission displays (hereinafter also referred to as “FED”). ) Is attracting attention.

Among such PDP member patterns, in particular, in recent years, a technique for forming electrode patterns with high definition has been strongly demanded.
As a method of forming an electrode as an FPD member, a photosensitive resin layer is formed on a substrate by screen printing or the like, and the photosensitive resin layer is irradiated with infrared rays or ultraviolet rays through a photomask on which a desired pattern is drawn. Then, development is performed to leave a desired pattern on the substrate, and a photolithography method for firing the pattern is known (see, for example, Patent Documents 1 to 3).
JP 09-142878 A JP 11-194493 A JP 2001-154345 A

In order to form a high-definition electrode pattern, high smoothness is required for the photosensitive resin layer formed on the substrate.
However, when a photosensitive resin layer is formed using a conventional photosensitive composition, a mesh mark may remain on the surface of the photosensitive resin layer, particularly when the photosensitive resin layer is formed on a glass substrate by a screen printing method. In addition, since the release of the plate is poor, the surface of the photosensitive resin layer is fuzzy, and the thickness of the photosensitive resin layer is uneven.

Moreover, the problem that the both ends of a pattern warp in the baking process after pattern formation also occurred.
An object of the present invention is to provide a photosensitive composition capable of forming a photosensitive resin layer that has high smoothness and does not warp at both ends of the pattern after firing, and can form a high-definition electrode pattern, Another object of the present invention is to provide a pattern forming method capable of forming a high-definition electrode pattern.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that by using a photosensitive composition containing conductive particles, glass particles, a specific polymer, a photopolymerizable monomer and a photopolymerizable compound, accuracy can be improved. The present inventors have found that a high pattern can be formed and have completed the present invention.

That is, the photosensitive composition according to the present invention includes at least
(A) conductive particles,
(B) glass particles,
(C) (c1) a polymer containing a structural unit represented by the following formula (1), and (c2) a structural unit containing a carboxyl group,

(In the above formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a methylene group or an alkylene group having 1 to ³ carbon atoms, and R ³ represents an alkyl group having 1 to 8 carbon atoms.)
It contains (D) a photopolymerizable monomer, and (E) a photopolymerization initiator.

As a preferred embodiment of the photosensitive composition according to the present invention, the polymer (C) further contains (c3) a structural unit derived from a hydroxyl group-containing (meth) acrylate compound,
The (C) polymer further contains (c4) a structural unit represented by the following formula (2),

(In the above formula (2), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents a C 1-8 alkyl group.)
Furthermore, (F) hydroxypropyl cellulose is contained in an amount of 0.5 to 10% by mass based on the total mass of the composition,
The (B) glass particles contain 50 to 80% by mass of bismuth oxide,
The said (B) glass particle is contained 5-20 mass% with respect to the total mass of a composition.

The pattern forming method according to the present invention includes:
Forming a photosensitive resin layer obtained from the photosensitive composition on a substrate;
A step of exposing the photosensitive resin layer to form a latent image of a pattern;
Developing the photosensitive resin layer on which the latent image of the pattern is formed to form a pattern;
And a step of firing the pattern.

  Moreover, the manufacturing method of the electrode for flat panel displays which concerns on this invention forms an electrode with the said pattern formation method, It is characterized by the above-mentioned.

  By using the photosensitive composition of the present invention, it is possible to form a photosensitive resin layer that does not warp at both ends of the pattern after firing while having high smoothness, and a high-definition electrode pattern can be formed. .

According to the pattern forming method of the present invention, a high definition pattern can be formed.
According to the flat panel display electrode manufacturing method of the present invention, it is possible to form a flat panel display electrode that can form a high-definition pattern and has excellent surface uniformity.

Hereinafter, the present invention will be described in detail.
<Photosensitive composition>
(A) Conductive Particles (A) Conductive particles constituting the photosensitive composition of the present invention include metals such as Ag, Au, Al, Ni, Ag—Pd alloy, Co, Cu and Cr, and their oxidation. The particle which consists of a thing can be mentioned.

  The average particle diameter of the conductive particles (A) in the photosensitive composition of the present invention is preferably 0.1 to 20 μm, more preferably 1 to 6 μm. (A) When the average particle diameter of the conductive particles is less than 2 μm, the ultraviolet rays irradiated at the time of exposure do not reach the depth of the film sufficiently due to light scattering in the photosensitive composition layer, resulting in a narrow development margin or a pattern The cross section becomes an inversely tapered shape, and both ends of the pattern may be warped in the subsequent baking process. (A) When the average particle diameter of the conductive particles exceeds 4 μm, the pattern linearity may be inferior or the resistance value after firing may be high.

  The content of the conductive particles (A) in the photosensitive composition of the present invention is usually 50 to 98% by mass, preferably 60 to 95% with respect to the total amount of the inorganic powder, that is, the conductive particles and the glass particles. % By mass.

(B) Glass Particles The (B) glass particles constituting the photosensitive composition of the present invention are not particularly limited as long as an electrode can be formed. A mixture of boron oxide, silicon oxide and aluminum oxide (B ₂ O ₃ —SiO ₂ —Al ₂ O ₃ series), II. A mixture of boron oxide, silicon oxide and zinc oxide (B ₂ O ₃ —SiO ₂ —ZnO system), III. Boron oxide, silicon oxide, aluminum oxide,
Examples thereof include a mixture of zinc oxide (B ₂ O ₃ —SiO ₂ —Al ₂ O ₃ —ZnO system).

  As a glass component of the (B) glass particle which comprises the photosensitive composition of this invention, it is preferable that content of a boron oxide is 30-70 mass%. Even if the content of boron oxide is outside this range, it is possible to form a good pattern shape. However, when boron oxide is less than 30% by mass, the refractive index increases and the glass softening point increases. There is a case. When boron oxide exceeds 70 mass%, chemical stability may be inferior.

  As the (B) glass particles constituting the photosensitive composition of the present invention, those containing bismuth oxide are particularly preferable. The content of bismuth oxide with respect to the total amount of (B) glass particles is preferably 50 to 80% by mass. is there.

  The glass particles (B) constituting the photosensitive composition of the present invention preferably have a softening point in the range of 400 to 600 ° C, and particularly preferably in the range of 450 to 580 ° C. Even if the softening point is less than 400 ° C. or exceeds 600 ° C. (B) Even if the glass powder has a good pattern shape, (B) the softening point of the glass powder is less than 400 ° C. In the firing process of the film-forming material layer with the composition, the glass powder is melted at a stage where organic substances such as the binder resin are not completely decomposed and removed. Part of the material may remain, resulting in an increase in the resistance of the resulting electrode. On the other hand, when the softening point of (B) the glass powder exceeds 600 ° C., it is necessary to perform baking at a temperature higher than 600 ° C., and thus the glass substrate is likely to be distorted.

  The refractive index of the glass particles (B) constituting the photosensitive composition of the present invention is preferably 1.5 to 1.8. If the refractive index of the glass particles is outside this range, the difference in refractive index from the refractive index of the binder resin becomes large, light scattering occurs in the photosensitive composition layer, and ultraviolet rays do not reach the depth of the film sufficiently. May be disadvantageous.

The particle size of the (B) glass particle which comprises the photosensitive composition of this invention becomes like this. Preferably it is 0.1-5 micrometers.
The content of (B) glass particles in the photosensitive composition of the present invention is based on the total amount of the inorganic powder.
Usually, it is 50 mass% or less, Preferably, it is 5-40 mass%.

Further, the content of the (B) glass particles in the photosensitive composition of the present invention is preferably 5 to 20% by mass with respect to the total amount of the composition.
(C) Polymer The (C) polymer constituting the photosensitive composition of the present invention contains (c1) a structural unit represented by the following formula (1) and (c2) a structural unit containing a carboxyl group. .

  (C) The polymer functions as a binder resin. (C) The polymer is an alkali-soluble resin. “Alkali-soluble” refers to a property of being dissolved in an alkaline developer and having solubility to such an extent that the intended development processing is performed. When an alkali-soluble resin is used as the binder resin, there is an advantage that, for example, the dissolution rate and the pattern shape in the alkali developer can be controlled by adjusting the content ratio of the structural unit that constitutes the carboxyl group. .

In the above formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a methylene group or an alkylene group having 1 to ³ carbon atoms, and R ³ represents an alkyl group having 1 to 8 carbon atoms.
R ² is particularly preferably an ethylene group, and R ³ is particularly preferably an ethyl group.

  (C1) The content ratio of the structural unit represented by the above formula (1), that is, the ratio of the portion constituted by (c1) the structural unit represented by the above formula (1) in the resin made of (C) polymer is 10 to 50% by mass is preferable.

Examples of monomers capable of forming a structural unit containing a carboxyl group by polymerization (c2) include, for example, acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid, mesaconic acid, cinnamic acid, Mention may be made of succinic acid mono (2- (meth) acryloyloxyethyl), ω-carboxy-polycaprolactone mono (meth) acrylate and the like.

  (C2) The content ratio of the structural unit containing a carboxyl group, that is, the ratio of the portion composed of the structural unit containing (c2) the carboxyl group in the resin comprising (C) the polymer is 5 to 30% by mass. It is preferable that

  The (C) polymer preferably further contains (c3) a structural unit derived from a hydroxyl group-containing (meth) acrylate compound. Examples of such hydroxyl group-containing (meth) acrylate compounds include hydroxyl group-containing monomers such as (meth) acrylic acid 2-hydroxyethyl, (meth) acrylic acid 2-hydroxypropyl, and (meth) acrylic acid 3-hydroxypropyl. And phenolic hydroxyl group-containing monomers such as o-hydroxystyrene, m-hydroxystyrene, and p-hydroxystyrene.

  The content ratio of the structural unit derived from the hydroxyl group-containing (meth) acrylate compound, that is, (C3) in the resin comprising the polymer, (c3) the portion composed of the structural unit derived from the hydroxyl group-containing (meth) acrylate compound The ratio is preferably 5 to 25% by mass.

  The polymer (C) preferably further contains (c3) a structural unit represented by the following formula (2) instead of or together with a structural unit derived from a hydroxyl group-containing (meth) acrylate compound. .

(In the above formula (2), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents a C 1-8 alkyl group.)
Examples of the compound that can form such a structural unit represented by (c4) formula (2) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) 2-ethylhexyl acrylate and the like.

  The content ratio of the structural unit represented by the formula (2) (c4), that is, the ratio of the portion composed of the structural unit represented by the formula (2) in the resin (C4) (c4) is: It is preferable that it is 10-70 mass%.

Furthermore, a polymer (C) can also contain the structural unit derived from monomers other than the above. As such monomers, monomers such as n-lauryl (meth) acrylate, benzyl (meth) acrylate, glycidyl (meth) acrylate, dicyclopentanyl (meth) acrylate (meth) acrylic acid other than those mentioned above Esters; acrylates having an α-hydroxymethyl group such as methyl-α- (hydroxymethyl) acrylate, ethyl-α- (hydroxymethyl) acrylate, n-butyl-α- (hydroxymethyl) acrylate; styrene, α-methyl Aromatic vinyl monomers such as styrene; Conjugated dienes such as butadiene and isoprene; One of polymer chains such as polystyrene, methyl poly (meth) acrylate, poly (meth) ethyl acrylate, poly (meth) acrylate benzyl, etc. Polymerizable unsaturated compounds such as (meth) acryloyl groups at the end of Examples thereof include a macromonomer having a sum group.

  Particularly preferred as the polymer (C) used in the composition of the present invention is methacrylic acid / 2-hydroxypropyl methacrylate / 2-ethylhexyl methacrylate copolymer / 2-ethoxyethyl methacrylate, methacrylic acid / Examples include 2-hydroxypropyl methacrylate / n-butyl methacrylate / 2-ethoxyethyl methacrylate copolymer.

  The polymer (C) preferably has a polystyrene-equivalent weight average molecular weight Mw measured by gel permeation chromatography of 5,000 to 5,000,000, more preferably 10,000 to 300,000. is there.

  Moreover, the glass softening point (Tg) of the said (C) polymer is -50 degreeC-50 degreeC. When the glass softening point (Tg) is lower than −50 ° C., the glass softening point (Tg) tends to swell during development and may have poor pattern linearity. When the glass softening point (Tg) is 50 ° C. or higher, warpage tends to occur at both ends of the pattern during the firing process.

  Moreover, as a content rate of the said (C) polymer in the photosensitive composition of this invention, it is 1-200 mass parts normally with respect to 100 mass parts of inorganic particles of (A) and (B), Preferably, it is 5-100 mass parts, Most preferably, it is 10-80 mass parts.

  (C) The polymer is, for example, (c1) a monomer that can form the structural unit represented by the above formula (1) and (c2) a monomer that can form a structural unit containing a carboxyl group, The hydroxyl group-containing (meth) acrylate compound and the (meth) acrylate compound represented by the above formula (3) can be obtained by copolymerization by a known copolymerization method.

(D) Photopolymerizable monomer The (D) photopolymerizable monomer that constitutes the composition of the present invention is a substance that is polymerized and cured by exposure and decreases in solubility in a developer. Examples of the photopolymerizable monomer (D) include substances that are polymerized by exposure to make the exposed part alkali-insoluble or alkali-insoluble. (D) When a substance that becomes alkali-insoluble or the like by such exposure is used as the photopolymerizable monomer, it becomes easy to provide contrast between the exposed and unexposed areas of the alkali developer, thereby increasing the pattern definition and pattern shape. There is an advantage that it becomes easy to control. Examples of the substance that is rendered insoluble in alkali by such exposure include, for example, an ethylenically unsaturated group-containing compound, preferably a polyfunctional (meth) acrylate compound.

Specific examples of the ethylenically unsaturated group-containing compound include di (meth) acrylates of alkylene glycol such as ethylene glycol and propylene glycol; di (meth) acrylates of polyalkylene glycol such as polyethylene glycol and polypropylene glycol; Di (meth) acrylates of hydroxylated polymers at both ends, such as hydroxypolybutadiene, hydroxyterminated polyisoprene at both ends, hydroxypolycaprolactone at both ends;
Poly (meth) acrylates of trihydric or higher polyhydric alcohols such as glycerin, 1,2,4-butanetriol, trimethylolalkane, tetramethylolalkane, pentaerythritol, dipentaerythritol; Poly (meth) acrylates of polyalkylene glycol adducts; poly (meth) acrylates of cyclic polyols such as 1,4-cyclohexanediol and 1,4-benzenediol; polyester (meth) acrylate, epoxy (meth) Examples thereof include oligo (meth) acrylates such as acrylate, urethane (meth) acrylate, alkyd resin (meth) acrylate, silicone resin (meth) acrylate, and spirane resin (meth) acrylate. It can be used in combination on.

  Among these, tripropylene glycol diacrylate (Tg: 90 ° C), tetraethylene glycol diacrylate (Tg: 50 ° C), trimethylolpropane PO-modified triacrylate (Tg: 50 ° C), urethane acrylate (Tg: 15 ° C) Bisphenol AEO-modified diacrylate (Tg: 75 ° C.) and the like are particularly preferably used.

  Moreover, the glass softening point (Tg) of the hardened | cured material formed by hardening | curing the (D) photopolymerizable monomer in the photosensitive composition of this invention becomes like this. Preferably it is 0-100 degreeC. When the glass softening point (Tg) is less than 0 ° C., the glass softening point tends to swell during development and the pattern linearity may be inferior. When the glass softening point (Tg) exceeds 100 ° C., warpage tends to occur at both ends of the pattern during the firing process.

The molecular weight of the (D) photopolymerizable monomer is preferably 100 to 2,000.
The content ratio of the photopolymerizable monomer (D) in the photosensitive composition of the present invention is usually 5 to 50 parts by mass with respect to 100 parts by mass of the inorganic particles (A) and (B), preferably 10 to 40 parts by mass.

(E) Photopolymerization initiator Specific examples of the (E) photopolymerization initiator used in the photosensitive composition of the present invention include benzyl, benzoin, benzophenone, camphorquinone, 2-hydroxy-2-methyl-1-phenyl. Propan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl- [4 ′-(methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl- Carbonyl compounds such as 2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one; azo compounds or azide compounds such as azoisobutyronitrile and 4-azidobenzaldehyde; mercaptan disulfide, bis (2, 4,6-trimethylbenzoyl) -phenylphosphine oxide Any organic sulfur compounds; organic peroxides such as benzoyl peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, paraffin hydroperoxide; 1,3-bis (trichloromethyl) -5 Trihalomethanes such as-(2'-chlorophenyl) -1,3,5-triazine, 2- [2- (2-furanyl) ethylenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine An imidazole dimer such as 2,2′-bis (2-chlorophenyl) 4,5,4 ′, 5′-tetraphenyl1,2′-biimidazole; These can be used alone or in combination of two or more.

As a content rate of the (E) photoinitiator in the composition of this invention, it is 5-100 mass parts normally with respect to 100 mass parts of photopolymerizable monomers, Preferably, it is 10-50 mass parts. .
(F) Hydroxypropylcellulose The photosensitive composition of the present invention can further contain (F) hydroxypropylcellulose.

The content ratio of the (F) hydroxypropyl cellulose is preferably 0.5 to 10% by mass with respect to the total mass of the composition.
<Solvent>
The photosensitive composition of the present invention usually contains a solvent for imparting appropriate fluidity or plasticity and good film forming properties. The solvent used has good affinity with inorganic particles, good solubility of alkali-soluble resin, can impart appropriate viscosity to the photosensitive composition, and can be easily removed by evaporation. It is preferable that

  Specific examples of the solvent include α-terpineol, β-terpineol, γ-terpineol, 1-hydroxy-p-menthane, 8-hydroxy-p-menthane, p-menthan-1-yl-acetate, p-menthane- 8-yl-acetate, terpinyloxyethanol, dihydroterpinyloxyethanol, terpinyl methyl ether, dihydroterpinyl methyl ether, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate Terpenes such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and other ether-based alcohols; acetic acid-n-butyl, acetic acid Saturated aliphatic monocarboxylic acid alkyl esters such as mill; Lactic acid esters such as ethyl lactate and lactic acid-n-butyl; Methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, ethyl-3-ethoxypropionate, etc. And ether esters, terpineol, butyl carbitol acetate, butyl carbitol, and the like.

The content ratio of the solvent in the photosensitive composition of the present invention can be appropriately selected within a range in which good film formability (fluidity or plasticity) is obtained.
<Additives>
In addition, the photosensitive composition of the present invention includes, as other optional components, pigments, thickeners, plasticizers, dispersants, development accelerators, adhesion assistants, antihalation agents, leveling agents, storage stabilizers, anti-foaming agents. Various additives such as a foaming agent, an antioxidant, an ultraviolet absorber, a sensitizer, and a chain transfer agent may be contained.

  The photosensitive composition of the present invention comprises (A) conductive particles, (B) glass particles, (C) a polymer, (D) a photopolymerization monomer and (E) a photopolymerization initiator, and if necessary ( F) It can be prepared by kneading the hydroxypropyl cellulose, the solvent and the above-mentioned other optional components using a kneader such as a roll kneader, a mixer, a homomixer, a ball mill, or a bead mill.

  The photosensitive composition prepared as described above is applied to the surface of the glass substrate directly by a conventionally known method for forming a film-forming material layer, that is, a screen printing method, and the coating film is dried. By doing so, it can be most suitably used in a method of forming a film forming material layer, that is, a photosensitive resin layer.

  The photosensitive composition prepared as described above is a paste-like composition having fluidity suitable for coating, and its viscosity is usually 1000 to 500,000 mPa · s, preferably 5,000 to 100. 1,000 mPa · s.

As drying conditions of a coating film, it is about 0.5 to 30 minutes at 50-150 degreeC, for example, and the residual ratio (content rate in the photosensitive resin layer) of the solvent after drying is usually within 2 mass%. is there.
The thickness of the photosensitive resin layer formed on the glass substrate as described above is, for example, 5 to 20 μm, although it varies depending on the content and size of inorganic particles.

<Pattern Forming Method and FPD Electrode Manufacturing Method>
In the pattern forming method of the present invention, the photosensitive composition of the present invention is used, and the composition is directly applied to the surface of a glass substrate by a screen printing method or the like to form a photosensitive resin layer on the substrate. The resin layer is exposed to form a pattern latent image, the photosensitive resin layer is developed to form a pattern layer, and the pattern layer is baked to form an inorganic pattern. The FPD electrode manufacturing method is characterized in that a panel electrode having an inorganic pattern is formed by this pattern forming method. Below, each process is demonstrated.

(I) Formation process of photosensitive resin layer A photosensitive resin layer can be formed by apply | coating the photosensitive composition of this invention on a board | substrate.

  Examples of the method for applying the photosensitive composition include various methods such as a screen printing method, a roll coating method, a spin coating method, and a casting coating method. After coating the photosensitive composition of the present invention, the coating film is dried. By this method, the photosensitive resin layer can be formed. Note that an n-layer stack may be formed by repeating the above steps n times.

(Ii) Exposure process A latent image of the pattern is formed on the surface of the photosensitive resin layer by a method of selectively irradiating (exposing) radiation such as ultraviolet rays through an exposure mask or a method of scanning with laser light. To do. Here, as the radiation irradiation apparatus, an ultraviolet irradiation apparatus generally used in a photolithography method, an exposure apparatus used when manufacturing a semiconductor and a liquid crystal display device, a laser apparatus, etc. are used. It is not limited.

(Iii) Development step The photosensitive resin layer on which the latent image of the pattern is formed by exposure is developed to form a pattern of the photosensitive resin layer. Here, as development processing conditions, depending on the type of photosensitive resin layer, the type / composition / concentration of developer, development time, development temperature, development method (for example, dipping method, rocking method, shower method, spray method) , Paddle method, etc.), developing device and the like can be selected as appropriate.

(Iv) Baking process The pattern of the photosensitive resin layer is baked to burn off the organic material in the remaining portion of the photosensitive resin layer. By this step, an electrode is formed from the pattern of the photosensitive resin layer.

  Here, the temperature of the baking treatment needs to be a temperature at which the organic substance in the photosensitive resin layer (residual portion) is burned off, and is usually 400 to 600 ° C. The firing time is usually 10 to 90 minutes.

Hereinafter, materials used in the above steps, various conditions, and the like will be described.
<Board>
Examples of the substrate material include plate-like members made of an insulating material such as glass, silicone, polycarbonate, polyester, aromatic amide, polyamideimide, and polyimide. For the surface of the plate-like member, chemical treatment with a silane coupling agent or the like, if necessary, plasma treatment; thin film formation treatment by an ion plating method, a sputtering method, a gas phase reaction method, a vacuum deposition method, etc. Such an appropriate pretreatment may be performed.

  In the present invention, it is preferable to use glass having heat resistance as the substrate. Preferred examples of the glass substrate include CP600V manufactured by Central Glass Co., Ltd. and PD200 manufactured by Asahi Glass Co., Ltd.

<Mask for exposure>
The exposure pattern of the exposure mask used in the exposure process according to the manufacturing method of the present invention is a stripe having a width of 10 to 500 μm, although it varies depending on the material.

<Developer>
As the developer used in the development step according to the production method of the present invention, an alkali developer can be preferably used.

  When an alkali-soluble resin is used as the binder resin, the inorganic particles contained in the photosensitive resin layer are uniformly dispersed by the alkali-soluble resin. By dissolving and washing, inorganic particles are simultaneously removed.

  As an active ingredient of the alkaline developer, for example, lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium hydrogen phosphate, diammonium hydrogen phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, ammonium dihydrogen phosphate , Inorganic such as potassium dihydrogen phosphate, sodium dihydrogen phosphate, lithium silicate, sodium silicate, potassium silicate, lithium carbonate, sodium carbonate, potassium carbonate, lithium borate, sodium borate, potassium borate, ammonia Alkaline compounds: tetramethylammonium hydroxide, trimethylhydroxyethylammonium hydroxide, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropyl Triethanolamine, and organic alkaline compounds such as ethanol amine.

  The alkaline developer can be prepared by dissolving one or more of the alkaline compounds in water. Here, the density | concentration of the alkaline compound in an alkaline developing solution is 0.001-10 mass% normally, Preferably it is 0.01-5 mass%. In addition, after the development process with an alkali developer is performed, a washing process is usually performed.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In the following, “part” means “part by mass”. Moreover, each evaluation method in an Example is shown below.

[Mw of alkali-soluble resin]
The weight average molecular weight in terms of polystyrene was measured by gel permeation chromatography (GPC) (trade name HLC-802A) manufactured by Tosoh Corporation.

[Glass transition temperature (Tg)]
The glass transition temperature (Tg) of the alkali-soluble resin and the ethylenically unsaturated group-containing compound was measured using a differential scanning calorimeter (DSC-60, manufactured by Shimadzu Corporation). The temperature was raised from room temperature to 300 ° C. at 30 ° C./min, held for 5 minutes, then cooled to −100 ° C. at 10 ° C./min, and then obtained from an endothermic curve when the temperature was raised at 10 ° C./min.

Moreover, Tg after photocuring was measured regarding the glass transition temperature (Tg) of an ethylenically unsaturated group containing compound. 100 parts of an ethylenically unsaturated group-containing compound, 10 parts of a photopolymerization initiator (2-methyl- [4 ′-(methylthio) phenyl] -2-morpholino-1-propanone), 500 parts of a solvent (terpineol) are prepared, A screen sample printed on a glass substrate, dried at 120 ° C. for 10 minutes, and exposed to 1000 mJ / cm ² with an ultra-high pressure mercury lamp (in terms of illuminance in i-line) was used as a measurement sample.

[Printability]
The coating film immediately after the photosensitive composition was applied on a glass substrate by screen printing was visually checked for the presence or absence of fuzz.
Fluff occurs: ×
No fuzzing: ○
[Pattern warpage after firing]
The fired panel on which the pattern is formed is cut into small pieces, the pattern cross section is observed with a scanning electron microscope (“S4200” manufactured by Hitachi, Ltd.), and the film thickness at the center of the pattern and the film thickness at the edge of the pattern after firing. Was measured. From these values, the warpage of the pattern after firing was evaluated by the following formula. In addition, the film thickness of the pattern edge part employ | adopted the larger value among the film thicknesses of both edge parts. (Height of electrode end portion / film thickness of electrode center portion) × 100
A numerical value of 1.5 or more according to the above formula: ×
Less than 1.5: ○
<Example 1>
(1) Preparation of photosensitive composition 100 parts of Ag powder (A1) (average particle size 1.2 μm) as conductive particles, Bi ₂ O ₃ —SiO ₂ —B ₂ O ₃ —ZnO-based glass (as glass particles) B1) 20 parts (average particle size 1.0 μm, softening point 477 ° C.), polymer (hereinafter referred to as “polymer (C1)”) 2-ethylhexyl (meth) acrylate / 2-ethoxyethyl methacrylate / methacrylic acid 2-hydroxypropyl / methacrylic acid = 32.5 / 30/15 / 22.5 (mass%) copolymer (Mw = 53,886, Tg = 20.0 ° C.) 17 parts, ethylenically unsaturated group-containing compound (Hereinafter referred to as “ethylenically unsaturated group-containing compound (D1)) 7.5 parts of trimethylolpropane PO-modified triacrylate (Tg = 50 ° C.), photopolymerization initiator (hereinafter referred to as“ photopolymerization initiator (E1) 2-methyl- [4 ′-(methylthio) phenyl] -2-morpholino-1-propanone, 1 part of 2,4-diethylthioxanthone, 1 part of 3-methacryloxypropyltrimethoxysilane, hydroxypropylcellulose A photosensitive composition (I) was prepared by kneading 1 part and 18 parts of dihydroterpineol as a solvent with a stirring deaerator and then dispersing with a three-roll.

(2) Formation of photosensitive resin layer After the photosensitive composition (I) was applied on a glass substrate by screen printing, it was dried in a clean oven at 100 ° C. for 10 minutes to form a photosensitive resin layer having a thickness of 9 μm. did.

(3) Exposure process of photosensitive resin layer For photosensitive resin layer formed on a glass substrate, g line is applied by an ultrahigh pressure mercury lamp through a striped negative exposure mask having a line width of 60 μm and a space width of 60 μm. (43
6 nm), h-line (405 nm), and i-line (365 nm). The exposure amount at that time was 500 mJ / cm ^{2 in} terms of illuminance measured by a 365 nm sensor.

(4) Development step For the exposed photosensitive resin layer, the photosensitive resin layer is developed for 60 seconds by a shower method using a 0.3 mass% sodium carbonate aqueous solution at a liquid temperature of 30 ° C. as a developer, Subsequently, it was washed with ultrapure water. Thereby, the uncured photosensitive resin layer not irradiated with ultraviolet rays was removed to form a photosensitive resin layer pattern. When this pattern was observed with an optical microscope, no development residue was observed on the unexposed portion of the substrate, and no pattern chipping was observed. Thus, the pattern shape after development was good.

(5) Firing step The glass substrate on which the pattern of the photosensitive resin layer was formed was baked for 10 minutes in a 580 ° C. temperature atmosphere in a baking furnace. When this pattern was observed with a scanning electron microscope, an electrode having a pattern width of 60 μm and a thickness of 4 μm was formed, and no warping was observed in the pattern shape, and a good panel material could be obtained. Thus, the pattern shape after baking was favorable.

The evaluation results are shown in Table 1.
<Example 2>
Ag powder (A2) (average particle diameter 1.6 μm) as conductive particles in the photosensitive composition (I)
) 100 parts, B2O3-ZnO-Bi2O3-based glass (B2) as glass particles (average composition of particle size 0.9 μm, softening point 414 ° C. was used in the same manner as in Example 1 to prepare photosensitive composition (II). Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same steps as in Example 1.

<Example 3>
Ag powder (A3) (average particle size 2.2 μm) as conductive particles in the photosensitive composition (I)
) 100 parts, instead of polymer (C1), as polymer (C2) (2-ethylhexyl (meth) acrylate / 2-ethoxyethyl methacrylate / 2-hydroxypropyl methacrylate / methacrylic acid = 40/35/15) A photosensitive composition (III) was prepared in the same manner as in Example 1, except that a / 10 (mass%) copolymer (Mw = 23,000, Tg = 5 ° C.) was used.
Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 1.

<Example 4>
As the conductive particles in the photosensitive composition (I), Ag powder (A1) (average particle size 1.2 μm)
m) A photosensitive composition (IV) was prepared in the same manner as in Example 1 except that 50 parts and (A2) (average particle size 1.6 μm) 50 parts were used. Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 1.

<Example 5>
As the conductive particles in the photosensitive composition (I), Ag powder (A1) (average particle size 1.2 μm)
m) A photosensitive composition (V) was prepared in the same manner as in Example 2 except that 50 parts and 50 parts of (A2) (average particle diameter 1.6 μm) were used. Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 1.

<Example 6>
As the conductive particles in the photosensitive composition (I), Ag powder (A1) (average particle size 1.2 μm)
m) A photosensitive composition (VI) was prepared in the same manner as in Example 3 except that 50 parts and 50 parts of (A2) (average particle diameter 1.6 μm) were used. Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 1.

<Example 7>
As the conductive particles in the photosensitive composition (I), Ag powder (A2) (average particle diameter 1.6 μm)
m) A photosensitive composition (VII) was prepared in the same manner as in Example 3 except that 20 parts and (A3) (average particle size 2.2 μm) 80 parts were used. Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 1.

<Comparative Example 1>
Instead of the alkali-soluble resin (C1) in the photosensitive composition (I), as the alkali-soluble resin (C3), methyl (meth) acrylate / 2-hydroxypropyl methacrylate / methacrylic acid = 62.5 / 15/22. A photosensitive composition (V) was prepared in the same manner as in Example 2 except that a 5 (mass%) copolymer (Mw = 51000, Tg = 110 ° C.) was used. Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 1.

  After firing, when observed with a scanning electron microscope, the upper pattern line width was 60 μm, and the lower pattern line width was 50 μm, which was an inversely tapered shape. Further, it was confirmed that the warp was 3 μm at both ends of the pattern, and a good panel material could not be obtained.

<Comparative Example 2>
Instead of the alkali-soluble resin (C1), as the alkali-soluble resin (C4), 2-ethylhexyl (meth) acrylate / methyl (meth) acrylate / 2-hydroxypropyl methacrylate / methacrylic acid = 32.5 / 30/15 A photosensitive composition (VI) was prepared in the same manner as in Example 1 except that a /22.5 (mass%) copolymer (Mw = 54000, Tg = 65.0 ° C.) was used. Table 1 shows the evaluation results of the photosensitive resin layer transferred, exposed, developed and baked in the same process as in Example 2.

  After firing, when observed with a scanning electron microscope, the upper pattern line width was 65 μm and the lower pattern line width was 60 μm. Further, warpage was observed at both ends of the pattern of 4 μm, and a good panel material could not be obtained.

Claims (8)

(A) conductive particles,
(B) glass particles,
(C) (c1) a polymer containing a structural unit represented by the following formula (1), and (c2) a structural unit containing a carboxyl group,

(In the above formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a methylene group or an alkylene group having 2 to 10 carbon atoms, and R ³ represents an alkyl group having 1 to 8 carbon atoms.)
A photosensitive composition comprising (D) a photopolymerizable monomer and (E) a photopolymerization initiator.   The photosensitive composition according to claim 1, wherein the (C) polymer further contains (c3) a structural unit derived from a hydroxyl group-containing (meth) acrylate compound. The photosensitive composition according to claim 1 or 2, wherein the polymer (C) further contains (c4) a structural unit represented by the following formula (2).

(In the above formula (2), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents a C 1-8 alkyl group.)   Furthermore, (F) 0.5-10 mass% of hydroxypropyl cellulose is contained with respect to the total mass of a composition, The photosensitive composition in any one of Claims 1-3 characterized by the above-mentioned.   The photosensitive composition according to claim 1, wherein the (B) glass particles contain 50 to 80 mass% of bismuth oxide.   The photosensitive composition according to any one of claims 1 to 5, wherein the glass particles (B) are contained in an amount of 5 to 20% by mass relative to the total mass of the composition. Forming a photosensitive resin layer obtained from the photosensitive composition according to any one of claims 1 to 6 on a substrate;
A step of exposing the photosensitive resin layer to form a latent image of a pattern;
Developing the photosensitive resin layer on which the latent image of the pattern is formed to form a pattern;
And a step of baking the pattern.   An electrode is formed by the pattern forming method according to claim 7, wherein the method for producing an electrode for a flat panel display.