JP2010039396A - Photosensitive paste composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive paste composition capable of obtaining a conductor pattern having a sufficient thixotropy property, preferable printing characteristics and developing property, and a low electric resistance value. <P>SOLUTION: The photosensitive paste composition contains (A) a conductive particle, (B) an alkaline soluble polymer, (C) polyfunctional (meth)acrylate compound, (D) a photopolymerization initiator, and (E) a silver oxide powder having a 1-1,000 nm average particle size. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a photosensitive paste composition, and more specifically, in the manufacture of a display panel such as a flat panel display and a circuit board having a fine circuit pattern used for advanced mounting materials for electronic components, a highly accurate pattern is provided. The present invention relates to a photosensitive paste composition that can be suitably used for forming.

  In recent years, a multilayer circuit board for mounting a large number of highly integrated LSIs and various electronic components, a plasma display panel (hereinafter also referred to as “PDP”), a field emission display (hereinafter also referred to as “FED”), and the like. In the flat panel display (hereinafter also referred to as “FPD”), there is an increasing demand for downsizing, high density, and high definition, and further high reliability is required.

  In the production of such multilayer circuit boards and FPDs, it is indispensable to miniaturize conductor patterns such as signal wiring layers, power supply wiring layers, and electrode layers in order to achieve miniaturization and high density. Conventionally, various methods have been proposed as a method for forming a fine conductor pattern. For example, (1) a conductive paste composition containing a non-photosensitive resin is applied to the surface of a substrate by screen printing. To form a resin layer having a required pattern, and by firing the resin layer, a screen printing method for forming a conductor pattern; (2) a conductive paste containing a photosensitive resin on the entire surface of the substrate; A resin layer is formed by applying the composition, and this resin layer is exposed to light or ultraviolet rays through a photomask having a desired pattern, and then developed to form a resin pattern layer. And the photolithographic method which forms a conductor pattern by baking this resin pattern layer is known (for example, patent document 1). Preliminary see Patent Document 2.).

When the conductive paste composition used for the formation of such a conductor pattern does not have sufficient thixotropy when applied to a substrate, the conductive pattern obtained is poor in printing characteristics such as plate separation. The surface smoothness of the conductive paste composition is low, and the inorganic particles in the conductive paste composition are precipitated, so the storage stability is low. When stored for a long period of time, it is difficult to redisperse the precipitated inorganic particles. Therefore, there is a problem that the conductive paste composition cannot be used.
Thus, in order to improve screen printing characteristics and sedimentation of inorganic particles, it has been proposed to use hydrogenated castor oil, fatty acid amide, surface-treated calcium carbonate, organic bentonite, silica powder, etc. as thixotropic agents. (For example, see Patent Document 3 and Patent Document 4).

  However, in such a conductive paste composition, when an organic thixotropic agent is used, there is a problem that the thixotropic agent inhibits development with an alkaline developer, while an inorganic thixotropic agent is used. In this case, since the thixotropic agent remains after the baking treatment, there is a problem that the electric resistance value of the obtained conductor pattern is increased.

Japanese Patent Laid-Open No. 11-44949 JP-A-11-219619 JP-A-11-317112 JP-A-11-154417

  The present invention has been made based on the above circumstances, and its purpose is to provide a conductor pattern having sufficient thixotropy, good printing characteristics and developability, and low electrical resistance. It is in providing the photosensitive paste composition obtained.

The photosensitive paste composition of the present invention comprises:
(A) conductive particles,
(B) an alkali-soluble polymer,
(C) a polyfunctional (meth) acrylate compound,
(D) a photopolymerization initiator, and (E) silver oxide particles having an average particle diameter of 1 to 1000 nm.

In the photosensitive paste composition of the present invention, (E) silver oxide particles have an average particle diameter of 1 to 1000 nm in a particle size distribution measurement by a laser method using a 0.2 mass% sodium hexametaphosphate aqueous solution as a dispersion medium. It is preferable to be in the range.
Moreover, it is preferable that (E) silver oxide particle contains 0.05-5 mass parts with respect to 100 mass parts of (A) electroconductive particle.
Further, (E) the silver oxide particles preferably have a specific surface area of 1.0 to 25.0 m ² / g by the BET method.
The (E) silver oxide grains preferably have a half-value width of the diffraction peak of the (111) plane by the X-ray diffraction method of 0.25 ° or more.

  According to the photosensitive paste composition of the present invention, since silver oxide particles having a particle size in a specific range are contained as a thixotropic agent, it has sufficient thixotropic properties, printing characteristics and developability are good, In addition, a conductor pattern having a low electrical resistance value can be obtained.

Hereinafter, the photosensitive paste composition of the present invention will be described in detail.
The photosensitive paste composition of the present invention comprises an A component composed of conductive particles, a B component composed of an alkali-soluble polymer, a C component composed of a polyfunctional (meth) acrylate compound, and a D composed of a photopolymerizable initiator. A component and an E component made of silver oxide particles are contained.

[Component A]
The conductive particles used as the component A are preferably made of metal, and specific examples thereof include Ag, Au, Al, Ni, Ag—Pd alloy, Co, Cu, and Cr. Of these, Ag is preferred.
Moreover, it is preferable that the average particle diameter of electroconductive particle is 0.1-10 micrometers, More preferably, it is 0.2-5 micrometers. When the average particle size of the conductive particles is too small, the specific surface area of the conductive particles is large, so that the particles are likely to aggregate and it may be difficult to obtain a stable dispersion state. On the other hand, when the average particle size of the conductive particles is excessive, it may be difficult to obtain a high-definition conductor conductor pattern.

[Component B] The alkali-soluble polymer used as the component B is dissolved in an alkaline developer and is soluble to such an extent that the desired development processing is performed.
Specific examples of such alkali-soluble polymers include (meth) acrylic resins, hydroxystyrene resins, novolac resins, polyester resins and the like.
Among such alkali-soluble polymers, particularly preferred are the following copolymer of monomer (a) and monomer (c), monomer (a), monomer (b) and monomer (c) Acrylic resins such as coalescence can be mentioned.

Monomer (I):
Monomers (a) are carboxyl group-containing monomers, and specific examples thereof include acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid, mesaconic acid, cinnamic acid, succinic acid. Examples include acid mono (2- (meth) acryloyloxyethyl), ω-carboxy-polycaprolactone mono (meth) acrylate, and the like.
Monomer (b):
The monomer (b) is an OH group-containing monomer, and specific examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 3-hydroxypropyl (meth) acrylate. Hydroxyl group-containing monomers such as o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, and the like.
Monomer (C):
The monomer (c) is a monomer copolymerizable with the monomer (b) or the monomer (b). Specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, and (meth) acrylic. Monomers such as n-butyl acid, 2-ethylhexyl (meth) acrylate, n-lauryl (meth) acrylate, benzyl (meth) acrylate, glycidyl (meth) acrylate, dicyclopentanyl (meth) acrylate ( (Meth) acrylic acid esters other than a); α-hydroxymethyl groups such as methyl-α- (hydroxymethyl) acrylate, ethyl-α- (hydroxymethyl) acrylate, n-butyl-α- (hydroxymethyl) acrylate An acrylate having an aromatic vinyl monomer such as styrene or α-methylstyrene; butadiene, Conjugated dienes such as isoprene; polymerizability such as (meth) acryloyl group at one end of polymer chain such as polystyrene, poly (meth) methyl acrylate, poly (meth) ethyl acrylate, poly (meth) acrylate benzyl, etc. And macromonomers having an unsaturated group.

  The copolymer of monomer (a) and monomer (c), and the copolymer of monomer (a), monomer (b) and monomer (c) are due to the presence of copolymer components derived from monomer (a). , Having alkali solubility. Among these, a copolymer of monomer (a), monomer (b), and monomer (c) is particularly preferable from the viewpoint of good dispersion stability of conductive particles as component A and solubility in an alkali developer described later.

  The content of the copolymer component derived from the monomer (a) in such a copolymer is preferably 5 to 60% by mass, particularly preferably 10 to 40% by mass, and the copolymer derived from the monomer (b). The content of the component is preferably 1 to 50% by mass, particularly preferably 5 to 30% by mass.

  Particularly preferred as the alkali-soluble polymer used in the photosensitive paste composition of the present invention is a methacrylic acid / 2-hydroxypropyl methacrylate / n-butyl methacrylate copolymer, methacrylic acid / succinic acid mono (2 -(Meth) acryloyloxyethyl) / 2-hydroxypropyl methacrylate / n-butyl methacrylate copolymer.

As the molecular weight of the alkali-soluble polymer, the polymerization average molecular weight Mw is preferably 5,000 to 5,000,000, and more preferably 10,000 to 300,000.
Moreover, as a content rate of the alkali-soluble polymer in the photosensitive paste composition of this invention, it is 1-200 mass parts normally with respect to 100 mass parts of electroconductive particles, Preferably, 5-100 mass parts, Especially preferably, it is 10-80 mass parts.

[C component]
The polyfunctional (meth) acrylate compound used as component C is polymerized by exposure in the presence of a photopolymerization initiator, which will be described later, so that the solubility in the developer is reduced, that is, it becomes alkali-insoluble or alkali-insoluble. It is a substance. By using a substance that becomes insoluble or hardly soluble in alkali by such exposure, it becomes easier to provide contrast between the exposed portion and the unexposed portion with respect to the alkaline developer, and it becomes easier to increase the definition of the conductor pattern and control the pattern shape. There is an advantage.

As a specific example of such a polyfunctional (meth) acrylate compound,
Di (meth) acrylates of alkylene glycols such as ethylene glycol and propylene glycol;
Di (meth) acrylates of polyalkylene glycols such as polyethylene glycol and polypropylene glycol;
Di (meth) acrylates of hydroxylated polymers at both ends such as both ends hydroxypolybutadiene, both ends hydroxypolyisoprene, and both ends hydroxypolycaprolactone; glycerin, 1,2,4-butanetriol, trimethylolalkane, tetramethylolalkane , Poly (meth) acrylates of trihydric or higher polyhydric alcohols such as pentaerythritol and dipentaerythritol;
Poly (meth) acrylates of polyalkylene glycol adducts of trihydric or higher polyhydric alcohols;
Poly (meth) acrylates of cyclic polyols such as 1,4-cyclohexanediol and 1,4-benzenediol;
Oligo (meth) acrylates such as polyester (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, alkyd resin (meth) acrylate, silicone resin (meth) acrylate, and spirane resin (meth) acrylate;
Or the propylene oxide (PO) modified substance etc. of these (meth) acrylates can be mentioned, These can be used individually or in combination of 2 or more types.
Of these, trimethylolpropane triacrylate, trimethylolpropane PO-modified triacrylate, and the like are particularly preferably used.
The molecular weight of the polyfunctional (meth) acrylate compound is preferably 100 to 2,000.

  Moreover, as a content rate of the polyfunctional (meth) acrylate compound in the photosensitive paste composition of this invention, it is 5-50 mass parts normally with respect to 100 mass parts of electroconductive particles, Preferably, it is 10-10. 40 parts by mass.

[Component D] Specific examples of the photopolymerization initiator used as the component D include benzyl, benzoin, benzophenone, camphorquinone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl. Ketone, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl- [4 ′-(methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4-morphol Carbonyl compounds such as linophenyl) -butan-1-one; azo compounds or azide compounds such as azoisobutyronitrile and 4-azidobenzaldehyde; mercaptan disulfide, bis (2,4,6-trimethylbenzoyl) -phen Organic sulfur compounds such as ruphosphine oxide; organic peroxides such as benzoyl peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, and paraffin hydroperoxide; 1,3-bis (trichloro Methyl) -5- (2′-chlorophenyl) -1,3,5-triazine, 2- [2- (2-furanyl) ethylenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine Trihalomethanes such as: 2,2′-bis (2-chlorophenyl) 4,5,4 ′, 5′-tetraphenyl 1,2′-biimidazole and other imidazole dimers; 2,4-dimethylthioxanthone, 2 , 4-diethylxanthone, 2-chlorothioxanthone, 2,4-diisopropylthiol Thioxanthone such as cantonal can be mentioned. These can be used alone or in combination of two or more.

  As a content rate of the photoinitiator in the photosensitive paste composition of this invention, it is 5-100 mass parts normally with respect to 100 mass parts of polyfunctional (meth) acrylate compounds, Preferably, 10-50 Part by mass.

[E component]
Silver oxide particles used as the E component are contained as a thixotropic agent.
Such silver oxide particles preferably have a specific surface area by the BET method of 1.0 to 25.0 m ² / g, more preferably 5 to 15 m ² / g. If this specific surface area is too small, it will be difficult to impart sufficient thixotropy to the resulting photosensitive paste composition. On the other hand, when this specific surface area is excessive, the interaction between particles in the resulting photosensitive paste composition, for example, the action due to intermolecular force or hydrogen bond is increased, so that the photosensitive paste composition is The problem of gelation arises.

The silver oxide particles have an average particle diameter of 1 to 1000 nm, preferably 50 to 110 nm. When this average particle diameter is too small, the silver oxide particles tend to aggregate, and thus the photosensitive paste composition gels. On the other hand, when the average particle size is excessive, it is difficult to impart sufficient thixotropy to the resulting photosensitive paste composition.
In addition, the silver oxide particles preferably have an average particle size in the above range in a particle size distribution measurement by a laser method using a 0.2 mass% sodium hexametaphosphate aqueous solution as a dispersion medium. In addition, the silver oxide particles may have one particle size distribution peak or a plurality of particle size distribution peaks in the above particle size distribution measurement.
Moreover, it is preferable that the half width of the diffraction peak of the (111) plane by an X-ray diffraction method is 0.25 degree or more, and, more preferably, it is 0.3-0.5 degree.

  As a content rate of the silver oxide particle in the photosensitive paste composition of this invention, it is preferable that it is 0.05-5 mass parts with respect to 100 mass parts of electroconductive particles, More preferably, it is 0.1-3. Part by mass. If this ratio is too small, it may be difficult to impart sufficient thixotropy to the resulting photosensitive paste composition, and it may be difficult to obtain a conductor pattern having a low electrical resistance value. Sometimes. On the other hand, when this ratio is excessive, there arises a problem that the photosensitive paste composition gels.

[Glass Particles] The photosensitive paste composition of the present invention can contain glass particles as necessary.
The average particle size of the glass particles is preferably 0.1 to 5 μm.
Moreover, it is preferable that the softening point of a glass particle is 350-700 degreeC, More preferably, it is 400-620 degreeC.
As a specific example of such glass particles,
I. A mixture of bismuth oxide, boron oxide, silicon oxide (Bi ₂ O ₃ —B ₂ O ₃ —SiO ₂ system),
II. A mixture of zinc oxide, boron oxide, silicon oxide (ZnO—B ₂ O ₃ —SiO ₂ system),
III. A mixture of boron oxide, silicon oxide, aluminum oxide (B ₂ O ₃ —SiO ₂ —Al ₂ O ₃ system),
IV. Examples thereof include particles made of a mixture of zinc oxide, boron oxide, silicon oxide (ZnO—B ₂ O ₃ —SiO ₂ system), and the like.
As a content rate of the glass particle in the photosensitive paste composition of this invention, it is preferable that it is 3-25 mass parts with respect to 100 mass parts of electroconductive particles, More preferably, it is 5-15 mass parts.

〔solvent〕
The photosensitive paste composition of the present invention usually contains a solvent for imparting appropriate fluidity or plasticity and good film forming properties. As the solvent used, the affinity with the conductive particles, the solubility with the alkali-soluble polymer, etc. are good, and the resulting photosensitive paste composition can be given an appropriate viscosity and dried. It is preferable that it can be easily removed by evaporation.

  Particularly preferred solvents include ketones, alcohols and esters (hereinafter referred to as “specific solvents”) having a normal boiling point (boiling point at 1 atm) of 100 to 200 ° C.

  Specific examples of such specific solvents include ketones such as diethyl ketone, methyl butyl ketone, dipropyl ketone, and cyclohexanone; n-pentanol, 4-methyl-2-pentanol, cyclohexanol, diacetone alcohol, dihydroxyterpineol, and the like. 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 aliphatics such as n-butyl acetate and amyl acetate Monocarboxylic acid alkyl esters; Lactic acid esters such as ethyl lactate and lactic acid-n-butyl; Methyl cellosolve acetate, ethyl cellosolve acetate, propylene And ether esters such as ethylene glycol monomethyl ether acetate and ethyl-3-ethoxypropionate. Among these, methyl butyl ketone, cyclohexanone, diacetone alcohol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether , Ethyl lactate, propylene glycol monomethyl ether acetate, ethyl-3-ethoxypropionate, dihydroxyterpineol and the like are preferable. These specific solvents can be used alone or in combination of two or more.

  Specific examples of the solvent that can be used other than the specific solvent include ethyl cellosolve, methyl cellosolve, terpineol, butyl carbitol acetate, butyl carbitol, isopropyl alcohol, and benzyl alcohol.

  The content ratio of the solvent in the photosensitive paste composition of the present invention can be appropriately selected within a range in which good film formability (fluidity or plasticity) is obtained.

〔Additive〕
Further, the photosensitive paste composition of the present invention includes, as optional components, a plasticizer, a dispersant, a development accelerator, an adhesion assistant, a coupling agent, an antihalation agent, a leveling agent, a storage stabilizer, an antifoaming agent, Various additives such as an antioxidant, an ultraviolet absorber, a sensitizer, and a chain transfer agent may be contained.

[Photosensitive paste composition]
The photosensitive paste composition of the present invention comprises the above conductive particles, alkali-soluble polymer, polyfunctional (meth) acrylate compound, photopolymerization initiator, silver oxide particles, solvent, and glass particles used as necessary and The additive can be prepared by kneading using a kneader such as a roll kneader, a mixer, a homomixer, a ball mill, or a bead mill.
The photosensitive paste composition thus prepared has a viscosity of usually 100 to 1,000,000 cp, preferably 500 to 300,000 cp.

[Pattern formation]
In the photosensitive paste composition of the present invention, for example, the photosensitive paste composition is applied to the surface of the substrate and dried to form a resin layer on the substrate, and the resin layer is exposed to light. Forming a latent image of a conductor pattern on the resin layer, developing the resin pattern layer to form a resin pattern layer, and baking the resin pattern layer to form a desired conductor pattern; it can.

(I) Resin layer forming step:
Formation of a resin layer is performed by apply | coating the photosensitive paste composition on a board | substrate, and drying-processing the obtained coating film.
The resin layer may be formed as a single-layer resin layer by performing the steps of applying the photosensitive paste composition and drying the coating film once, but applying the photosensitive paste composition and drying the coating film. A resin layer made of a laminate may be formed by repeating the treatment step a plurality of times.
As a method for applying the photosensitive paste composition to the substrate, various methods such as a screen printing method, a roll coating method, a spin coating method, and a casting coating method can be used.
As drying treatment conditions for the coating film, for example, the drying temperature is 50 to 150 ° C. and the drying time is 0.5 to 30 minutes. Further, the residual ratio of the solvent after drying (content in the resin layer) is usually within 2% by mass.
The thickness of the resin layer varies depending on the content and size of the conductive particles, but is, for example, 1 to 500 μm.

  As the substrate, for example, a plate-like member made of an insulating material such as glass, silicone, polycarbonate, polyester, aromatic amide, polyamideimide, or polyimide can be used. 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.

(Ii) Exposure process:
The exposure treatment of the resin layer is performed by a method of selectively irradiating the resin layer with radiation such as ultraviolet rays through an exposure mask, a method of scanning the resin layer with laser light, or the like. 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, and the like can be used. There is no particular limitation.

(Iii) Development processing step:
The development processing of the resin layer is performed by, for example, washing with water after dissolving an unexposed portion of the resin layer with an alkali developer.
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 above alkaline compounds in water or the like.
As a development processing method, an immersion method, a rocking method, a shower method, a spray method, a paddle method, or the like can be used.
Specific conditions for the development treatment, such as development time and development temperature, are appropriately set according to the type of photosensitive paste composition used, the type of developer, the composition and concentration, the development method, and the like.

(Iv) Firing process:
The baking process of the resin pattern layer is performed by heating the resin pattern layer.
Moreover, a baking process is performed on the conditions which the organic substance in a resin pattern layer burns, and a baking process temperature is 400-600 degreeC and baking time is 10 to 90 minutes normally.

  According to the above photosensitive paste composition, the silver oxide particles having a particle size in a specific range are contained as a thixotropic agent, so that the thixotropic agent has sufficient thixotropy, printing characteristics in screen printing, and an alkaline developer. As a result, a conductive pattern with good developability and low electrical resistance can be obtained.

  Hereinafter, specific examples of the present invention will be described, but the present invention is not limited thereto. In the following, “part” means “part by mass”.

The silver oxide particles used in the following examples and comparative examples have a specific surface area according to the BET method, an average particle size and a particle size by a particle size distribution measurement by a laser method using a 0.2 mass% sodium hexametaphosphate aqueous solution as a dispersion medium. The number of distribution peaks and the half width of the diffraction peak on the (111) plane according to the X-ray diffraction method are as follows.
Silver oxide particles (E1):
Specific surface area 14.0 m ² / g, average particle size 60.0 nm, number of peaks in particle size distribution 1, half width of diffraction peak of (111) plane by X-ray diffraction method 0.31 °
Silver oxide particles (E2):
Specific surface area 11.3 m ² / g, average particle size 80.0 nm, number of peak of particle size distribution 1, half width of diffraction peak of (111) plane by X-ray diffraction method 0.33 °
Silver oxide particles (E3):
Specific surface area of 6.1 m ² / g, average particle diameter of 100.0 nm, number of peak of particle size distribution, half width of diffraction peak of (111) plane by X-ray diffraction method 0.34 °
Silver oxide particles (E4):
Specific surface area 0.9 m ² / g, average particle size 2000.0 nm, number of peak of particle size distribution 1, half width of diffraction peak of (111) plane by X-ray diffraction method 0.34 °

Moreover, each evaluation method in the following Examples and Comparative Examples is shown below.
[TI value of composition]
The viscosity of the photosensitive paste composition was measured under the conditions of shear rate 2 s ^-1 and 20 s ^-1 , and the TI value (= viscosity V ₂ measured at shear rate 2 s ^-1 / viscosity V measured at shear rate 20 s ^-1). ₂₀ ). Here, the TI (thixotropic index) value is an index indicating the structural viscosity. The larger the TI value, the more the structural viscosity is, and the more excellent the printing characteristics and the storage stability. The closer it is, the more the Newtonian fluid behaves, so the printing characteristics are poor and the particles are likely to settle.

[Composition release]
Observe the plate separation when the photosensitive paste composition is applied on a glass substrate by screen printing, ○ if the photosensitive paste composition is separated from the printing plate immediately after application, after application, the photosensitive paste from the printing plate A case where a slight time difference is observed until the composition leaves, Δ, a case where a time difference is recognized until the photosensitive paste composition leaves from the printing plate after coating, and an in-plane variation in film thickness occurs, and x. Indicated.

[Volume resistance of conductor pattern]
A photosensitive paste composition is applied and baked on a glass substrate, a conductor pattern of 100 μm × 10 cm is formed by the above-described method, and an electrical resistance value measured by a “resistance meter 3541” manufactured by HIOKI and the thickness of the conductor pattern The volume resistance [μΩ · cm was calculated from the cross-sectional area obtained from the above.

<Example 1>
(1) Preparation of photosensitive paste composition:
As component A, 50 parts of silver particles having an average particle diameter of 1.2 μm and 50 parts of silver particles having an average particle diameter of 1.6 μm, and Bi ₂ O ₃ —SiO ₂ —B ₂ O ₃ —ZnO-based glass (average particle diameter) as glass particles 1.0 μm, softening point 477 ° C.) 8 parts, as component B 2-ethylhexyl (meth) acrylate / 2-ethoxyethyl methacrylate / 2-hydroxypropyl methacrylate / methacrylic acid = 35.0 / 37.5 / 15 /12.5 (mass%) copolymer (Mw = 43000, Tg = 2.4 ° C., hereinafter referred to as “alkali-soluble resin (B1)”) 13 parts, trimethylolpropane PO modified triacrylate ( Tg = 50 ° C., hereinafter referred to as “polyfunctional (meth) acrylate (C1)”) 6 parts, 2-methyl- [4 ′-(methylthio) phenyl] -2-morpholine as D component 2 parts of non-1-propanone (hereinafter referred to as “photopolymerization initiator (D1)”) and 1 part of 2,4-diethylthioxanthone (hereinafter referred to as “photopolymerization initiator (D2)”), coupling 1 part of 3-methacryloxypropyltrimethoxysilane as an agent, 0.1 part of silver oxide particles (E1) as an E component, and 24 parts of dihydroterpineol as a solvent are kneaded with a stirring deaerator and then dispersed with a three-roller. Thus, a photosensitive paste composition (I) was prepared.
About the obtained photosensitive paste composition (I), while measuring TI value, evaluation of the plate release property in screen printing was performed. The results are shown in Table 1.

(2) Formation of resin layer:
After the photosensitive paste 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 resin layer having a thickness of 9 μm.

(3) Resin layer exposure treatment:
The g-line (436 nm), h-line (405 nm), and i-line are applied to the resin layer formed on the glass substrate 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. The resin layer was exposed by irradiation with (365 nm) mixed light. The exposure amount was 500 mJ / cm ^{2 in} terms of illuminance measured with a 365 nm sensor.

(4) Development processing of resin layer:
For the exposed resin layer, a 0.3% by mass sodium carbonate aqueous solution having a liquid temperature of 30 ° C. was used as a developer, and the resin layer was developed for 60 seconds by a shower method, and then ultrapure water was used. Washed with water. This removed the unexposed part of the resin layer that was not irradiated with ultraviolet rays, thereby forming a resin pattern layer. When this resin pattern layer was observed with an optical microscope, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed, and the shape was good. .

(5) Baking treatment of resin pattern layer:
The glass substrate on which the resin pattern layer was formed was heated in a baking furnace in a temperature atmosphere of 580 ° C. for 10 minutes, whereby the resin pattern layer was baked. When the surface of the substrate was observed with a scanning electron microscope, a conductor pattern with a pattern width of 60 μm and a thickness of 4 μm was formed, and no warp was found in the conductor pattern, and the shape was good.
And the volume resistance of the obtained conductor pattern was measured. The results are shown in Table 1.

<Example 2>
A photosensitive paste composition (II) was prepared in the same manner as in Example 1 except that the amount of silver oxide particles (E1) was changed from 0.1 part to 0.5 part, and the measurement of the TI value and Evaluation of release properties was performed. Further, using the photosensitive paste composition (II), in the same manner as in Example 1, by forming a resin layer, exposing, developing, and baking the resin pattern layer, a conductor pattern is formed, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 3>
A photosensitive paste composition (III) was prepared in the same manner as in Example 1 except that the amount of the silver oxide particles (E1) was changed from 0.1 part to 1.0 part. Evaluation of release properties was performed. In addition, using the photosensitive paste composition (III), in the same manner as in Example 1, by forming a resin layer, exposing, developing, and firing the resin pattern layer, a conductor pattern is formed, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 4>
A photosensitive paste composition (IV) was prepared in the same manner as in Example 1 except that 0.1 part of silver oxide particles (E2) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed. In addition, using the photosensitive paste composition (IV), in the same manner as in Example 1, by forming a resin layer, exposing, developing, and baking the resin pattern layer, a conductor pattern is formed, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 5>
A photosensitive paste composition (V) was prepared in the same manner as in Example 1 except that 0.5 part of silver oxide particles (E2) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed. In addition, using the photosensitive paste composition (V), in the same manner as in Example 1, a conductor pattern is formed by performing resin layer formation, exposure processing, development processing, and resin pattern layer baking processing, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 6>
A photosensitive paste composition (VI) was prepared in the same manner as in Example 1 except that 1.0 part of silver oxide particles (E2) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed. Further, using the photosensitive paste composition (VI), in the same manner as in Example 1, a conductor pattern was formed by performing resin layer formation, exposure processing, development processing, and resin pattern layer firing processing, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 7>
A photosensitive paste composition (VII) was prepared in the same manner as in Example 1 except that 0.1 part of silver oxide particles (E3) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed. Further, using the photosensitive paste composition (VII), in the same manner as in Example 1, by forming a resin layer, exposing, developing, and baking the resin pattern layer, a conductor pattern is formed, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 8>
A photosensitive paste composition (VIII) was prepared in the same manner as in Example 1 except that 0.5 part of silver oxide particles (E3) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed. In addition, using the photosensitive paste composition (VIII), in the same manner as in Example 1, by forming a resin layer, exposing, developing, and baking the resin pattern layer, a conductor pattern is formed, The volume resistance was measured. The results are shown in Table 1. In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Example 9>
A photosensitive paste composition (IX) was prepared in the same manner as in Example 1 except that 1.0 part of silver oxide particles (E3) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed. Also, using the photosensitive paste composition (IX), in the same manner as in Example 1, a conductor pattern was formed by performing resin layer formation, exposure treatment, development treatment, and resin pattern layer firing treatment, The volume resistance was measured. The results are shown in Table 1.
In addition, after the development process, the resin pattern layer was observed with an optical microscope. As a result, no undeveloped residue was observed in the portion where the unexposed portion of the substrate was formed, and no pattern chipping was observed. It was something.
Further, when the surface of the substrate was observed with a scanning electron microscope after the baking treatment, a conductor pattern having a pattern width of 60 μm and a thickness of 4 μm was formed, and the conductor pattern was not warped and the shape was good. It was something.

<Comparative Example 1>
A photosensitive paste composition (X) was prepared in the same manner as in Example 1 except that 0.5 part of silver oxide particles (E4) was used instead of 0.1 part of silver oxide particles (E1). Measurement of TI value and evaluation of release property were performed.
Further, using the photosensitive paste composition (X), in the same manner as in Example 1, a conductor pattern is formed by performing resin layer formation, exposure treatment, development treatment, and resin pattern layer baking treatment, The volume resistance was measured. The results are shown in Table 1.

<Comparative example 2>
Photosensitivity was the same as in Example 1 except that 1.0 part of silica powder having an average particle size of 100.0 nm and a specific surface area of 100 m ² / g was used instead of 0.1 part of silver oxide particles (E1). A paste composition (XI) was prepared, and the TI value was measured and the release property was evaluated.
In addition, using the photosensitive paste composition (XI), in the same manner as in Example 1, a conductor pattern is formed by performing resin layer formation, exposure processing, development processing, and resin pattern layer baking processing, The volume resistance was measured. The results are shown in Table 1.

As is clear from the results in Table 1, the photosensitive paste compositions according to Examples 1 to 9 have a large TI value, sufficient thixotropy, good plate separation in screen printing, and It was confirmed that a conductor pattern having a low resistance value was formed. In addition, it was confirmed that any of the photosensitive paste compositions according to Examples 1 to 9 formed a pattern having a good shape after the development process and the baking process.
On the other hand, since the photosensitive paste composition according to Comparative Example 1 has a large particle size of the silver oxide particles and a small specific surface area, it has a TI value of 1 and does not have sufficient thixotropy. The plate separation in screen printing was bad.
Moreover, since the photosensitive paste composition which concerns on the comparative example 2 uses the silica powder instead of the silver oxide particle, the electrical resistance value of the obtained conductor pattern was high.

Claims (5)

(A) conductive particles,
(B) an alkali-soluble polymer,
(C) a polyfunctional (meth) acrylate compound,
A photosensitive paste composition comprising (D) a photopolymerization initiator, and (E) silver oxide particles having an average particle diameter of 1 to 1000 nm.   (E) The silver oxide particles have an average particle size in the range of 1 to 1000 nm in a particle size distribution measurement by a laser method using a 0.2 mass% sodium hexametaphosphate aqueous solution as a dispersion medium. The photosensitive paste composition described in 1.   (A) 0.05-5 mass parts of (E) silver oxide particles contain with respect to 100 mass parts of electroconductive particles, The photosensitive paste composition of Claim 1 or Claim 2 characterized by the above-mentioned. 4. The photosensitive paste composition according to claim 1, wherein the silver oxide particles have a specific surface area of 1.0 to 25.0 m ² / g by BET method.   5. The photosensitive according to claim 1, wherein the silver oxide particles have a half-value width of a diffraction peak of a (111) plane by an X-ray diffraction method of 0.25 ° or more. Paste composition.