JP7230347B2 - PHOTOSENSITIVE PASTE, CURED FILM USING THE SAME, FIRED BODY, ELECTRONIC COMPONENT, AND MANUFACTURING METHOD THEREOF - Google Patents

Description

TECHNICAL FIELD The present invention relates to a photosensitive paste, a cured film using the same, a sintered body, an electronic component, and a method for producing the same.

With the spread of communication devices such as smartphones and tablets, the electronic components mounted on them are becoming smaller and more efficient. required to form.

Examples of photosensitive pastes used for pattern formation by photolithography include photosensitive conductive pastes containing alkali-soluble resins, photopolymerizable monomers, oxime ester photopolymerization initiators, cellulose resins, and conductive powders (e.g., patent documents 1) has been proposed.

Therefore, as a photosensitive paste capable of forming a fine pattern, for example, a photosensitive paste containing an inorganic powder, an alkali-soluble resin, a reactive compound having an isocyanuric acid structure or a maleimide structure, a photosensitive agent and a solvent (for example, Patent Document 2 See), and a polymer having a photopolymerizable functional group and a carbon-nitrogen bond, a polymer having a glass transition temperature of 70 to 150 ° C. and having no carbon-nitrogen bond, and a photopolymerizable functional group and a photosensitive resin composition containing a photopolymerization initiator (see, for example, Patent Document 3).

Japanese Unexamined Patent Application Publication No. 2013-80020 WO2018/038074 JP 2017-181960 A

However, the photosensitive pastes and photosensitive resin compositions described in Patent Documents 2 and 3 are diced (cut while heating the formed pattern) in response to an increase in the number of pattern layers that accompanies the miniaturization of electronic components. There was a problem that it was easy to stick in the process. Adhesion in the dicing process causes contamination of the dicing apparatus and a decrease in production efficiency, and thus reduction of the adhesion is required.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a photosensitive paste that can form a fine pattern and can suppress adhesion in a dicing process.

The above object is achieved by the following technical means.
An inorganic powder (a), an alkali-soluble resin (b-1) having no photoreactive functional group and an acid value of 200 to 300 mgKOH/g, a reactive compound (c) and a photoreaction initiator (d) further comprising (b-2) an alkali-soluble resin having a photoreactive functional group , wherein the alkali-soluble resin (b-1) comprises (meth)acrylic acid/methyl (meth)acrylate/styrene copolymer , a photosensitive paste containing 20 to 40 parts by weight of the alkali-soluble resin (b-1) with respect to a total of 100 parts by weight of the alkali-soluble resin (b-1) and the alkali-soluble resin (b-2).

According to the photosensitive paste of the present invention, it is possible to form a fine pattern and suppress adhesion in the dicing process.

The photosensitive paste of the present invention comprises an inorganic powder (a), an alkali-soluble resin (b-1) having no photoreactive functional group and an acid value of 200 to 300 mgKOH/g (hereinafter referred to as "alkali-soluble resin ( b-1)”), a reactive compound (c) and a photoreaction initiator (d) , and further comprising (b-2) an alkali-soluble resin having a photoreactive functional group, 20 to 40 parts by weight of the alkali-soluble resin (b-1) is contained with respect to a total of 100 parts by weight of the alkali-soluble resin (b-1) and the alkali-soluble resin (b-2). The inorganic powder (a) is melted or fused by heat firing to form an inorganic sintered body having functions such as conductivity, dielectricity and magnetism. By containing the alkali-soluble resin (b-1), solubility in an alkaline developer can be imparted, and adhesion in the dicing process can be suppressed. Inclusion of the reactive compound (c) and the photoreaction initiator (d) imparts photocurability and enables pattern formation by photolithography. In the present invention, it is important that the alkali-soluble resin (b-1) has no photoreactive functional group and an acid value of 200 to 300 mgKOH/g. As described above, conventionally known photosensitive pastes have the problem that they tend to stick together in the dicing process as the number of pattern layers increases. The present inventors have found that by including the specific alkali-soluble resin (b-1), sticking in the dicing process can be suppressed. In the present invention, attention is paid to the acid value of an alkali-soluble resin having no photoreactive functional group. Alkali-soluble resins having a photoreactive functional group are crosslinked by exposure to light, and the acid value increases after curing. The acid value fluctuates little before and after curing, and the desired effect can be easily obtained by limiting the numerical value of the acid value. By setting the acid value of the alkali-soluble resin that does not have a photoreactive functional group to 200 mgKOH/g or more, the degree of freedom of the resin is reduced due to the interaction of hydrogen bonds between the alkali-soluble resins, and adhesion in the dicing process is suppressed. can do. On the other hand, by setting the acid value of the alkali-soluble resin having no photoreactive functional group to 300 mgKOH/g or less, it is possible to suppress pattern peeling in the development process and form a fine pattern.

Inorganic powder (a) refers to a powder composed of an inorganic component. Examples of the inorganic powder (a) include silver, copper, gold, platinum, palladium, tungsten, molybdenum, tin, nickel, aluminum, ruthenium, silicon, titanium, indium, iron, cobalt, chromium, carbon, alumina ( _Al2 O ₃ ), zirconia (ZrO ₂ ), silica (SiO ₂ ), titania (TiO ₂ ), magnesia (MgO), beryllia (BeO), mullite ( _{3Al 2} O 3.2SiO ₂ ), cordierite ( _5SiO 2.2Al _2O3.2MgO ), spinel ( _MgO.Al2O3 ) _, forsterite ( _{2MgO.SiO2 ) ,} anorthite ( _{CaO.Al2O3.2SiO2 )} , _Sergian ( _{BaO.Al2O3.2SiO 2} ) Powders of metals such as aluminum nitride (AlN), ferrite (garnet type: Y ₃ Fe ₅ O ₁₂ system, spinel type: MeFe ₂ O ₄ system), metal compounds, and alloys thereof; glass-ceramic composite powder etc. You may contain 2 or more types of these.

Among these, a conductive powder is preferable for imparting conductivity after heating and firing, a dielectric powder is preferable for imparting dielectric properties after heating and firing, and a dielectric powder is preferable for imparting magnetism after heating and firing. , magnetic powder is preferred. As the conductive powder, powders of silver, copper, gold, platinum, palladium, tungsten, molybdenum, etc. are preferable, and silver powder is more preferable. Preferred dielectric powders include powders of alumina, silica, zirconia, titania, etc., and glass-ceramic composite powders. Powders of nickel, iron, cobalt, chromium, ferrite, etc. are preferable as the magnetic powder. Among these, conductive powder is more preferred, and silver powder is even more preferred.

The median diameter (D50) in the particle size distribution (number basis) of the inorganic powder (a) is preferably 1.0 to 3.5 μm. By setting the D50 of the inorganic powder (a) to 1.0 μm or more, the exposed light in the exposure/development steps described later can be efficiently transmitted, curing can be sufficiently progressed to the bottom, and pattern peeling can be suppressed. , a finer pattern can be formed. D50 of the inorganic powder (a) is more preferably 1.3 μm or more, further preferably 1.6 μm or more. On the other hand, by setting the D50 of the inorganic powder (a) to 3.5 μm or less, it is possible to suppress the residue in the exposure/development process and form a finer pattern. D50 of the inorganic powder (a) is more preferably 2.7 μm or less, further preferably 2.4 μm or less. The D50 of the inorganic powder (a) can be measured by a laser light scattering method using Microtrac HRA (Model No. 9320-X100; manufactured by Nikkiso Co., Ltd.).

The content of the inorganic powder (a) in the photosensitive paste is preferably 85-92% by weight based on the total solid content. By setting the content of the inorganic powder (a) to 85% by weight or more, adhesion in the dicing process can be further suppressed. Moreover, in the firing step described later, the probability of contact between the inorganic powders (a) can be improved, and disconnection of the pattern can be suppressed. The content of the inorganic powder (a) is more preferably 87% by weight or more. On the other hand, by setting the content of the inorganic powder (a) to 92% by weight or less, it is possible to suppress pattern peeling in the exposure/development process and form a finer pattern. The content of the inorganic powder (a) is more preferably 90% by weight or less. Here, the total solid content of the photosensitive paste refers to all constituent components of the photosensitive paste, excluding the organic solvent.

The content of the inorganic powder (a) in the photosensitive paste was measured by measuring the weight of the paste dry film obtained by applying and drying the photosensitive paste and removing the organic solvent, and then measuring the cross section perpendicular to the dry film surface with a transmission type. Observe with an electron microscope (for example, "JEM-4000EX" manufactured by JEOL Ltd.), and perform image analysis by distinguishing the inorganic powder (a) from other components by the density of the image. Volume of the inorganic powder (a) The fraction can be calculated and obtained from the product of the densities of the inorganic powder (a) and other components. At this time, the observation area of the transmission electron microscope is about 20 μm×100 μm, and the magnification is about 1,000 to 3,000 times. Moreover, when the blending amount of each component of the photosensitive paste is known, the content of the inorganic powder (a) can also be calculated from the blending amount.

In the photosensitive paste of the present invention, the alkali-soluble resin means a resin having an alkali-soluble group. Examples of alkali-soluble groups include carboxyl groups, phenolic hydroxyl groups, sulfonic acid groups, and thiol groups. A carboxyl group is preferred because of its high solubility in an alkaline developer.

Alkali-soluble resin (b-1) does not have a photoreactive functional group. Since it does not have a photoreactive functional group, it does not undergo cross-linking due to exposure, so that the acid value fluctuates less before and after curing, and the desired effect can be easily obtained by limiting the acid value. Here, the photoreactive functional group refers to a functional group having radical polymerizability. Examples of photoreactive functional groups include (meth)acryl groups, allyl groups, vinyl groups, and mercapto groups. You may have 2 or more types of these. Among these, a (meth)acryl group is preferred.

It is important that the acid value of the alkali-soluble resin (b-1) is 200-300 mgKOH/g. When the acid value is less than 200 mgKOH/g, interaction due to hydrogen bonding between the alkali-soluble resins (b-1) becomes small, and the degree of freedom of the resin increases, so sticking tends to occur in the dicing step. The acid value of the alkali-soluble resin (b-1) is preferably 220 mgKOH/g or more. On the other hand, when the acid value of the alkali-soluble resin (b-1) exceeds 300 mgKOH/g, the elution rate of the alkali-soluble resin (b-1) is high in the exposure/development steps described below, and pattern peeling is likely to occur. Formation of fine patterns becomes difficult. The acid value of the alkali-soluble resin (b-1) is preferably 280 mgKOH/g or less. The acid value of the alkali-soluble resin (b-1) can be determined by neutralization titration using an aqueous potassium hydroxide solution.

The weight average molecular weight (Mw) of the alkali-soluble resin (b-1) is preferably 20,000 to 50,000. By setting the Mw of the alkali-soluble resin (b-1) to 20,000 or more, sticking in the dicing process can be further suppressed. In addition, it is possible to suppress pattern peeling in the exposure/development process and form a finer pattern. The Mw of the alkali-soluble resin (b-1) is more preferably 23,000 or more, even more preferably 32,000 or more. On the other hand, by setting the Mw of the alkali-soluble resin (b-1) to 50,000 or less, it is possible to improve the solubility in the developer in the exposure/development process, suppress the residue, and form a finer pattern. can be done. The Mw of the alkali-soluble resin (b-1) is more preferably 45,000 or less, even more preferably 42,000 or less. The Mw of the alkali-soluble resin (b-1) is a polystyrene-equivalent value and can be measured using high-performance liquid chromatography (Alliance 2695; manufactured by Nippon Waters Co., Ltd.) or the like.

As the alkali-soluble resin (b-1), an acrylic resin is preferable, and a copolymer of an acrylic monomer having a carbon-carbon double bond and another monomer is preferable. Acrylic monomers having a carbon-carbon double bond include, for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, n-pentyl acrylate, isodecyl acrylates, isooctyl acrylate, 2-ethylhexyl acrylate, allyl acrylate, lauryl acrylate, stearyl acrylate, and other chain aliphatic hydrocarbon group-containing acrylates having 1 to 18 carbon atoms; benzyl acrylate, phenyl acrylate, 1-naphthyl acrylate , 2-naphthyl acrylate and the like having a cyclic aromatic hydrocarbon group of 6 to 10 carbon atoms; cyclohexyl acrylate, dicyclopentanyl acrylate, 4-tert-butylcyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopenta Examples include acrylates having a cycloaliphatic hydrocarbon group with 6 to 15 carbon atoms such as dienyl acrylate, isobornyl acrylate, 3,3,5-trimethylcyclohexyl acrylate, and those obtained by replacing these acrylates with methacrylates. . You may use 2 or more types of these. Among these, methyl acrylate and methyl methacrylate are preferred. Examples of copolymerization components other than acrylic monomers include styrenes such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, chloromethylstyrene, and hydroxymethylstyrene; acrylic acid; Examples include unsaturated carboxylic acids such as methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid and vinylacetic acid, and acid anhydrides thereof. You may use 2 or more types of these. Among these, styrene, acrylic acid, and methacrylic acid are preferred.

The alkali-soluble resin (b-1) is preferably a (meth)acrylic acid/methyl (meth)acrylate/styrene copolymer, which can further suppress sticking in the dicing process.

The content of the alkali-soluble resin (b-1) in the photosensitive paste is preferably 0.5 to 5.0% by weight based on the total solid content. By setting the content of the alkali-soluble resin (b-1) to 0.1% by weight or more, sticking in the dicing process can be further suppressed. The content of the alkali-soluble resin (b-1) is more preferably 1.0% by weight or more, more preferably 1.3% by weight or more. On the other hand, by setting the content of the alkali-soluble resin (b-1) to 5.0% by weight or less, pattern peeling due to excessive elution of the alkali-soluble resin (b-1) in the development process is suppressed, and the Fine patterns can be formed. The content of the alkali-soluble resin (b-1) is more preferably 4.0% by weight or less, and even more preferably 3.0% by weight or less.

The photosensitive paste of the present invention may further contain an alkali-soluble resin (b-2) having a photoreactive functional group (hereinafter sometimes referred to as "alkali-soluble resin (b-2)"). preferable. By including the alkali-soluble resin (b-2) in addition to the alkali-soluble resin (b-1), curing in the exposure step described later is promoted, pattern peeling in the development step is suppressed, and a finer pattern is formed. be able to. The photoreactive functional group is as described in the alkali-soluble resin (b-1).

The glass transition point of the alkali-soluble resin (b-2) is preferably 80 to 160°C. By setting the glass transition point of the alkali-soluble resin (b-2) to 80° C. or higher, adhesion in the dicing step can be further suppressed. The glass transition point of the alkali-soluble resin (b-2) is more preferably 100° C. or higher. On the other hand, by setting the glass transition point of the alkali-soluble resin (b-2) to 160° C. or lower, the thermal decomposability is improved, firing defects caused by residual organic components during firing are suppressed, and a finer pattern can be obtained. can be formed. The glass transition point of the alkali-soluble resin (b-2) is more preferably 140° C. or lower. When two or more alkali-soluble resins (b-2) having different glass transition points are contained, the glass transition points of all the alkali-soluble resins (b-2) are preferably within the above range. The glass transition point of the alkali-soluble resin (b-2) can be measured by differential scanning calorimetry (DSC) using a differential scanning calorimeter (DSC-50; Shimadzu Corporation).

Examples of alkali-soluble resins having a glass transition point of 80 to 160° C. include “Cychromer” (registered trademark) P (ACA) Z200M, P (ACA) Z230AA, P (ACA) Z250, P (ACA) Z251, P (ACA)Z300, P(ACA)Z320, P(ACA)Z254F (manufactured by Daicel-Ornex Co., Ltd.) and the like.

The content of the alkali-soluble resin (b-2) in the photosensitive paste is preferably 1.0 to 10.0% by weight based on the total solid content. By setting the content of the alkali-soluble resin (b-2) to 1.0% by weight or more, cross-linking in the exposure/development process is promoted, pattern peeling is suppressed, and finer patterns can be formed. The content of the alkali-soluble resin (b-2) is more preferably 2.0% by weight or more, more preferably 3.5% by weight or more. On the other hand, by setting the content of the alkali-soluble resin (b-2) to 10.0% by weight or less, sticking in the dicing process can be further suppressed. The content of the alkali-soluble resin (b-2) is more preferably 8.0% by weight or less, more preferably 6.0% by weight or less.

Moreover, it is preferable to contain 20 to 40 parts by weight of the alkali-soluble resin (b-1) with respect to a total of 100 parts by weight of the alkali-soluble resin (b-1) and the alkali-soluble resin (b-2). By setting the content of the alkali-soluble resin (b-1) to 20 parts by weight or more, sticking in the dicing process can be further suppressed. On the other hand, by setting the content of the alkali-soluble resin (b-1) to 40 parts by weight or less, pattern peeling due to excessive elution of the alkali-soluble resin (b-1) in the development process is further suppressed, and finer pattern can be formed.

A reactive compound (c) in the present invention refers to a monomer or oligomer having a carbon-carbon double bond. Structures having a carbon-carbon double bond include, for example, an acrylic group, a methacrylic group, a vinyl group, a maleimide ring, and the like. A maleimide ring is more preferable from the viewpoint of further suppressing adhesion in the dicing step. Examples of the reactive compound (c) having an acrylic group include 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, dipenta Erythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, triglycerol diacrylate, trimethylolpropane triacrylate, bisphenol A diacrylate, isocyanurate acid EO-modified triacrylate and the like. Examples of the reactive compound (c) having a methacrylic group include those obtained by replacing these acrylates with methacrylates. Examples of the reactive compound (c) having a vinyl group include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, cyclohexyl vinyl ether, phenyl vinyl ether, ethylene glycol monovinyl ether, and triallyl isocyanurate. Examples of the reactive compound (c) having a maleimide ring include, for example, “Imilex” (registered trademark) P (N-phenylmaleimide), “Imilex” C (N-cyclohexylmaleimide) (trade names, Japan Co., Ltd. Catalyst), BMI-1000 (4,4-diphenylmethanebismaleimide), BMI-2000 (phenylmethanemaleimide), BMI-4000 (bisphenol A diphenyletherbismaleimide), BMI-7000 (4-methyl-1,3-phenylene bismaleimide) (these are trade names, manufactured by Daiwa Kasei Kogyo Co., Ltd.) and the like. Two or more of these may be included. Among these, N-phenylmaleimide is more preferable from the viewpoint of further suppressing adhesion in the dicing process and from the viewpoint of suppressing residue in the developing process to form a finer pattern.

The content of the reactive compound (c) in the photosensitive paste is preferably 0.5 to 5.0% by weight based on the total solid content. By setting the content of the reactive compound (c) to 0.5% by weight or more, it is possible to accelerate the hardening of the pattern in the exposure/development process, suppress pattern peeling, and form a finer pattern. The content of the reactive compound (c) is more preferably 1.0% by weight or more. On the other hand, by setting the content of the reactive compound (c) to 5.0% by weight or less, the sensitivity of the photosensitive paste can be appropriately maintained, the residue in the development process can be further suppressed, and a finer pattern can be formed. can be done. The content of the reactive compound (c) is more preferably 3.5% by weight or less.

The photoreaction initiator (d) in the present invention refers to a compound that absorbs short wavelength light such as ultraviolet rays and decomposes, or that generates radicals through a hydrogen abstraction reaction. Examples of the photoreaction initiator (d) that absorbs and decomposes light such as ultraviolet rays include 1,2-octanedione, benzophenone, methyl ortho-benzoylbenzoate, 4,4′-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4-benzoyl-4'-methyldiphenylketone, dibenzylketone, 2,2'-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy- 2-methylpropiophenone, Michler's ketone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 4-azidobenzalacetophenone, 2,6-bis(p-azidobenzylidene)cyclohexanone, Alkylphenone photoinitiators such as 6-bis(p-azidobenzylidene)-4-methylcyclohexanone; 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)- Acylphosphine oxide photoinitiators such as phenylphosphine oxide; 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-2(2-methyl benzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime), 1-phenyl-1,2-butanedione-2-(O-methoxycarbonyl)oxime, 1-phenyl-propanedione-2- (O-ethoxycarbonyl)oxime, 1-phenyl-propanedione-2-(O-benzoyl)oxime, 1,3-diphenyl-propanetrione-2-(O-ethoxycarbonyl)oxime, 1-phenyl-3-ethoxy -propanetrione-2-(O-benzoyl)oxime oxime ester photoreaction initiators. Examples of photoinitiators (d) that generate radicals by hydrogen abstraction include benzophenone, anthraquinone, thioxanthone, and phenylglyoxylic acid methyl ester. Two or more of these may be included. Among these, oxime ester-based photoreaction initiators are preferable from the viewpoint of improving the sensitivity during exposure, suppressing pattern peeling, and forming finer patterns.

The content of the photoinitiator (d) in the photosensitive paste is preferably 0.1 to 5.0% by weight. By setting the content of the photoreaction initiator (d) to 0.1% by weight or more, the sensitivity in the exposure/development process can be improved, pattern peeling can be suppressed, and a finer pattern can be formed. The content of the photoreaction initiator is more preferably 0.5% by weight or more. On the other hand, by setting the content of the photoreaction initiator (d) to 5.0% by weight or less, light absorption on the surface of the dry film in the exposure/development process is moderately suppressed, residue is suppressed, and a finer pattern is obtained. can be formed. The content of the photoinitiator (d) is more preferably 3.5% by weight or less.

The photosensitive paste of the present invention preferably further contains an organic solvent (e). Examples of the organic solvent (e) include N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2-pyrrolidone, dimethylimidazolidinone, dimethylsulfoxide, diethylene glycol methyl ether, diethylene glycol ethyl ether, and diethylene glycol propyl. Ether, diethylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, propylene glycol butyl ether, ethylene glycol butyl ether, tripropylene glycol methyl ether, tripropylene glycol butyl ether, diethylene glycol monoethyl ether acetate, dipropylene glycol methyl Ether acetate, propylene glycol phenyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol butyl ether acetate, γ-butyrolactone, ethyl acetoacetate, ethyl lactate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, ethylene glycol mono-n- Propyl ether, diacetone alcohol, tetrahydrofurfuryl alcohol, propylene glycol monomethyl ether acetate, cyclohexanol acetate, 2-(4-methylcyclohex-3-enyl)propan-2-ol and the like. You may contain 2 or more types of these.

The SP value of the organic solvent (e) is preferably 20.5 to 24.6 (J/cm ³ ) ^1/2 from the viewpoint of suppressing the residue and forming a finer pattern. Examples of the organic solvent (e) having an SP value of 20.5 to 24.6 (J/cm ³ ) ^1/2 include N,N-dimethylformamide, N-methyl-2-pyrrolidone, tripropylene glycol methyl ether, tripropylene glycol butyl ether, propylene glycol phenyl ether, 1-ethoxy-2-propanol, ethylene glycol propyl ether, diacetone alcohol, dipropylene glycol methyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, 2-(4-methylcyclohex-3-enyl)propan-2-ol, propylene glycol butyl ether, ethylene glycol butyl ether, γ-butyrolactone, ethyl acetoacetate and the like. You may contain 2 or more types of these. Among these, dipropylene glycol methyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, 2-(4-methylcyclohex-3-enyl)propane -2-ol, propylene glycol butyl ether, ethylene glycol butyl ether are more preferred. The SP value of the organic solvent (e) can be calculated from the molecular structure of the organic solvent (e) using the Fedors calculation method.

The content of the organic solvent (e) in the photosensitive paste of the present invention is preferably 5-20% by weight. By setting the content of the organic solvent (e) to 5% by weight or more, an increase in viscosity during the coating process can be suppressed. On the other hand, by setting the content of the organic solvent (e) to 20% by weight or less, adhesion in the dicing process can be further suppressed and finer patterns can be formed.

The organic solvent (e) includes a low boiling point organic solvent (e-1) having a boiling point of 150°C to 200°C and a high boiling point organic solvent (e-2) having a boiling point of 201°C to 250°C. is preferred. By including the low-boiling organic solvent (e-1), the residual organic solvent after drying can be reduced, and adhesion in the dicing step can be further suppressed. On the other hand, by including the high boiling point organic solvent (e-2), excessive volatilization of the organic solvent in the coating process can be suppressed, and an increase in viscosity can be suppressed. Here, the boiling point of the organic solvent (e) is disclosed in various documents and shall be rounded off to the first decimal place. Examples of the low boiling point organic solvent (e-1) include dipropylene glycol methyl ether, diethylene glycol methyl ether, propylene glycol butyl ether, ethylene glycol butyl ether and the like. Examples of the high-boiling organic solvent (e-2) include dipropylene glycol propyl ether, dipropylene glycol butyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, and 2-(4-methylcyclohex-3-enyl)propane. -2-ol and the like.

The content of the low boiling point organic solvent (e-1) in the photosensitive paste of the present invention is preferably 1.0 to 15.0% by weight. By setting the content of the low boiling point organic solvent (e-1) to 1.0% by weight or more, the residual amount of the organic solvent (e) after drying can be reduced, and adhesion in the dicing step can be further suppressed. . On the other hand, by setting the content of the low boiling point organic solvent (e-1) to 15.0% by weight or less, it is possible to suppress an increase in viscosity due to excessive volatilization of the organic solvent (e) in the coating step.

The content of the high boiling point organic solvent (e-2) in the photosensitive paste of the present invention is preferably 1.0 to 15.0% by weight. By setting the content of the high-boiling organic solvent (e-2) to 1.0% by weight or more, it is possible to suppress an increase in viscosity due to excessive volatilization of the organic solvent (e) in the coating step. On the other hand, by setting the content of the high boiling point organic solvent (e-2) to 15.0% by weight or less, the residual amount of the organic solvent (e) after drying is reduced, and adhesion in the dicing process is further suppressed. can be done.

Further, 25 to 65 parts by weight of the low boiling point organic solvent (e-1) is added to a total of 100 parts by weight of the low boiling point organic solvent (e-1) and the high boiling point organic solvent (e-2) in the photosensitive paste. It is preferable to contain. By setting the content of the low-boiling-point organic solvent (e-1) to 25 parts by weight or more, the residual amount of the organic solvent (e) after drying can be reduced, and adhesion in the dicing step can be further suppressed. The content of the low boiling point organic solvent (e-1) is more preferably 35 parts by weight or more. On the other hand, by setting the content of the low-boiling organic solvent (e-1) to 65 parts by weight or less, the increase in viscosity due to excessive volatilization of the organic solvent (e) during continuous printing in the coating process is suppressed, and continuous Printability can be improved. The content of the low boiling point organic solvent (e-1) is more preferably 55 parts by weight or less.

The photosensitive paste of the present invention may contain additives such as a plasticizer, a leveling agent, a sensitizer, a dispersant, a silane coupling agent, an antifoaming agent, and a pigment as long as the desired properties are not impaired. .

The photosensitive paste of the present invention can be obtained, for example, by mixing and/or dispersing the aforementioned components (a) to (e) and, if necessary, other additives. Apparatuses for mixing and/or dispersing include, for example, dispersers such as three rollers and ball mills, kneaders, and the like.

Next, the cured film of the present invention will be described. The cured film of the present invention is a film obtained by curing the photosensitive paste of the present invention and preferably has a film thickness of 5 to 30 μm. By setting the film thickness of the cured film to 5 μm or more, disconnection during firing can be further suppressed. On the other hand, by setting the film thickness of the cured film to 30 μm or less, adhesion in the dicing process can be further suppressed.

The cured film of the present invention may have a predetermined pattern shape. Examples of pattern shapes include linear shapes and spiral shapes. Regarding the pattern shape, the minimum width is preferably 10 to 30 μm. By setting the pattern width to 10 μm or more, disconnection during firing can be suppressed. On the other hand, by setting the pattern width to 30 μm or less, a finer pattern can be formed.

The cured film of the present invention can be obtained, for example, by coating the photosensitive paste of the present invention on a substrate, drying it, and photocuring it by exposure. When producing a pattern-shaped cured film, the pattern may be formed by developing after pattern exposure.

Examples of coating methods in the coating step include spray coating, roll coating, screen printing, and coating methods using blade coaters, die coaters, calendar coaters, meniscus coaters, and bar coaters. The film thickness of the coating film can be appropriately selected according to the coating method, the solid content concentration and viscosity of the photosensitive paste, and the like.

Examples of the drying method include heat drying using a heating device such as an oven, a hot plate, and infrared rays, and vacuum drying. The heating temperature is preferably 50 to 100°C. By setting the drying temperature to 50° C. or higher, the organic solvent (e) can be efficiently volatilized and removed, and adhesion in the dicing step can be further suppressed. On the other hand, by setting the drying temperature to 100° C. or lower, thermal crosslinking of the photosensitive paste can be suppressed, and residue in the non-exposed areas in the exposure/development steps can be suppressed to form finer patterns. The heating time is preferably 3 minutes to several hours.

As the exposure method, there are a method of exposure through a photomask and a method of exposure without using a photomask. As an exposure method without using a photomask, there is a method of exposing the entire surface and direct drawing using a laser beam or the like. methods and the like. Examples of the exposure apparatus include a stepper exposure machine, a proximity exposure machine, and the like. Actinic rays for exposure include, for example, near-ultraviolet rays, ultraviolet rays, electron beams, X-rays, and laser light, and ultraviolet rays are preferred. Examples of the ultraviolet light source include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, halogen lamps, germicidal lamps, etc. Ultra-high-pressure mercury lamps are preferred.

Examples of developing solutions for alkali development include tetramethylammonium hydroxide, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, and dimethyl acetate. Aqueous solutions of aminoethyl, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, hexamethylenediamine and the like can be mentioned. Polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide and γ-butyrolactone; alcohols such as methanol, ethanol and isopropanol; and ethyl lactate. , esters such as propylene glycol monomethyl ether acetate; cyclopentanone, cyclohexanone, isobutyl ketone; ketones such as methyl isobutyl ketone; surfactants and the like.

The development method includes, for example, a method of spraying the developer while the substrate on which the cured film is formed after exposure is left stationary or rotated, a method of immersing the substrate on which the cured film is formed after exposure in the developer, For example, a method of applying ultrasonic waves while immersing the base material on which the cured film after exposure is formed in the developing solution can be used.

The cured film obtained by development may be rinsed with a rinse liquid. Examples of the rinse liquid include water; aqueous solutions of alcohols such as ethanol and isopropyl alcohol; aqueous solutions of esters such as ethyl lactate and propylene glycol monomethyl ether acetate.

The cured film of the present invention can also be laminated to form a laminate. The number of layers to be laminated is preferably 1 to 30 layers. By setting the number of layers to be one or more, the thickness of the predetermined pattern can be increased. On the other hand, by setting the number of layers to be 30 or less, the influence of misalignment between layers can be reduced.

Next, the sintered body of the present invention will be explained. The sintered body of the present invention is obtained by sintering the cured film of the present invention, and its shape does not matter. The thickness of the sintered body is preferably 2 to 20 μm. By setting the thickness of the sintered body to 2 μm or more, disconnection during sintering can be suppressed. On the other hand, by setting the thickness of the sintered body to 20 μm or less, swelling during sintering can be suppressed.

The line width of the sintered body of the present invention is preferably 5 to 20 μm. By setting the line width of the sintered body to 5 μm or more, disconnection during sintering can be suppressed. On the other hand, by setting the line width of the fired body to 20 μm or less, a finer pattern can be formed.

The sintered body of the present invention can be obtained, for example, by sintering the cured film of the present invention or a laminate thereof. Examples of the firing method include a method of heat-treating at 300-600° C. for 5 minutes-several hours and then further heat-treating at 850-900° C. for 5 minutes-several hours.

The electronic component of the present invention preferably has a sintered body, an insulating ceramic layer and terminal electrodes. As the sintered body, the sintered body of the present invention described above is preferable, and as the insulating ceramic layer, one obtained by sintering a ceramic green sheet is preferable. By having an insulating ceramics layer, it is possible to suppress unintended short circuits between fired bodies. The terminal electrodes are preferably placed outside the sintered body and the insulating ceramic layer. Examples of materials that constitute the terminal electrodes include nickel and tin.

The method of manufacturing an electronic component of the present invention preferably includes the steps of applying a photosensitive paste, drying, and exposing and developing. As an example of the method of manufacturing an electronic component according to the present invention, a method of manufacturing a multilayer chip inductor will be described below.

First, a via hole is formed in a ceramic green sheet, and an interlayer connection wiring is formed by embedding a conductor in the via hole. Examples of the via hole forming method include laser irradiation. As a method of embedding a conductor in a via hole, for example, a method of embedding a conductor paste by a screen printing method and drying the paste can be used. Conductive pastes include, for example, pastes containing copper, silver, and silver-palladium alloys. The above-described photosensitive paste of the present invention is preferable because the interlayer connection wiring and the internal wiring can be formed at once to simplify the process.

Internal wiring is formed on the ceramic green sheet on which the interlayer connection wiring is formed. Examples of the method for forming the internal wiring include a photolithography method using a photosensitive paste. As the photosensitive paste, the above-described photosensitive paste of the present invention can be preferably used because it can suppress adhesion in the dicing process. If necessary, further dielectric patterns or insulator patterns are formed. A method for forming the dielectric pattern and the insulator pattern includes, for example, a screen printing method.

Next, a plurality of ceramic green sheets on which interlayer connection wirings and internal wirings are formed are laminated and thermocompression bonded to obtain a laminate. As a lamination method, for example, there is a method of stacking ceramic green sheets using guide holes. Examples of the thermocompression bonding apparatus include a hydraulic press machine. The thermocompression bonding temperature is preferably 90 to 130° C., and the thermocompression pressure is preferably 5 to 20 MPa.

A laminated chip inductor can be obtained by dicing the obtained laminate into a desired chip size, firing, applying terminal electrodes, and plating. Examples of the dicing device include a dice cutting machine. The temperature for dicing is preferably 80.degree. C. to 110.degree. Examples of the firing method include a method of heat-treating at 300-600° C. for 5 minutes-several hours and then further heat-treating at 850-900° C. for 5 minutes-several hours. Examples of the method of applying the terminal electrode include a sputtering method. Examples of metals used for plating include nickel and tin.

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these.

<Raw materials for photosensitive paste>
The raw materials used are as follows.

<Inorganic powder>
(a-1) Inorganic powder: Ag powder with D50 of 2.0 μm (a-2) Inorganic powder: Ag powder with D50 of 2.4 μm (a-3) Inorganic powder: Ag powder with D50 of 1.6 μm (a -4) Inorganic powder: Ag powder with D50 of 2.7 μm (a-5) Inorganic powder: Ag powder with D50 of 1.3 μm (a-6) Inorganic powder: Ag powder with D50 of 3.5 μm (a-7 ) Inorganic powder: Ag powder with D50 of 1.0 μm (a-8) Inorganic powder: Alumina powder with D50 of 4.2 μm (a-9) Inorganic powder: Silica powder with D50 of 0.8 μm In addition, inorganic powder (a ), the median diameter in the particle size distribution (number basis) was measured by a laser scattering method using a particle size distribution analyzer (Microtrac HRA Model No. 9320-X100; manufactured by Nikkiso Co., Ltd.).

<Alkali-soluble resin>
(b-1a) Alkali-soluble resin: acrylic resin copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/23/23 High performance liquid chromatography (Alliance 2695; manufactured by Nippon Waters Co., Ltd.) The weight average molecular weight (Mw) of the alkali-soluble resin (b-1a) was 35,000. In addition, the acid value measured by dissolving the (b-1a) alkali-soluble resin in an aqueous solution of methanol/water = 50/50 (weight ratio) and performing neutralization titration using a 1% by weight aqueous potassium hydroxide solution is It was 250 mg KOH/g. The Mw and acid value of the alkali-soluble resins (b-1) and (b-2) were also measured in the same manner.
(b-1b) Alkali-soluble resin: acrylic resin (Mw 35,000, acid value 220 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 50/27/23
(b-1c) Alkali-soluble resin: Acrylic resin (Mw 35,000, acid value 280 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 58/19/23
(b-1d) Alkali-soluble resin: Acrylic resin (Mw 35,000, acid value 200 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 46/31/23
(b-1e) Alkali-soluble resin: Acrylic resin (Mw 35,000, acid value 300 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 62/19/19
(b-1f) Alkali-soluble resin: Acrylic resin (Mw 35,000, acid value 100 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 30/35/35
(b-1g) Alkali-soluble resin: acrylic resin (Mw 35,000, acid value 400 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 85/8/7
(b-1h) Alkali-soluble resin: Acrylic resin (Mw 32,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/20/26
(b-1i) Alkali-soluble resin: Acrylic resin (Mw 42,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/26/20
(b-1j) Alkali-soluble resin: Acrylic resin (Mw 22,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/16/30
(b-1k) Alkali-soluble resin: Acrylic resin (Mw 46,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/30/16
(b-1l) Alkali-soluble resin: Acrylic resin (Mw 16,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/6/46
(b-1m) Alkali-soluble resin: acrylic resin (Mw 66,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate/styrene = 54/40/6
(b-1n) Alkali-soluble resin: Acrylic resin (Mw 35,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/methyl methacrylate = 54/46
(b-1o) Alkali-soluble resin: Acrylic resin (Mw 35,000, acid value 250 mgKOH/g) copolymerized at a molar ratio of methacrylic acid/styrene = 54/46
(b-2a) Alkali-soluble resin: "Cychromer" (registered trademark) P (ACA) Z250 (acrylic resin, Mw 22,000, acid value 35 mgKOH/g; manufactured by Daicel Allnex Co., Ltd.)
(b-2b) Alkali-soluble resin: "Cychromer" P(ACA) Z320 (acrylic resin, Mw 23,000, acid value 126 mgKOH/g; manufactured by Daicel Allnex Co., Ltd.).

<Reactive compound>
(c-1) Reactive compound: “Imilex” (registered trademark) P (N-phenylmaleimide; manufactured by Nippon Shokubai Co., Ltd.)
(c-2) Reactive compound: “Imilex” C (N-cyclohexylmaleimide; manufactured by Nippon Shokubai Co., Ltd.)
(c-3) Reactive compound: DPHA (dipentaerythritol hexaacrylate; manufactured by Daicel-Ornex Co., Ltd.)
(c-4) Reactive compound: M-315 (isocyanuric acid EO-modified triacrylate; manufactured by Toagosei Co., Ltd.)
(c-5) Reactive compound: BMI-1000 (4,4'-diphenylmethanebismaleimide; manufactured by Daiwa Kasei Kogyo Co., Ltd.).

<Photoinitiator>
(d-1) Photoinitiator: OXE-01 (1.2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)]; manufactured by BASF Japan Ltd.)
(d-2) Photoinitiator: OXE-02 (ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime) ; manufactured by BASF Japan Ltd.)
(d-3) Photoreaction initiator: IC-819 (bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; manufactured by BASF Japan Ltd.).

<Organic solvent>
(e-1a) Hi-solve DPM (dipropylene glycol methyl ether, boiling point 188°C, SP value 21.9 (J/cm ³ ) ^1/2 ; manufactured by Toho Chemical Industry Co., Ltd.)
(e-1b) Hisolve DM (diethylene glycol methyl ether, boiling point 193° C., SP value 23.0 (J/cm ³ ) ^1/2 ; manufactured by Toho Chemical Industry Co., Ltd.)
(e-1c) Ethyl acetoacetate (ethyl acetoacetate, boiling point 188° C., SP value 21.5 (J/cm ³ ) ^1/2 ; manufactured by Tokyo Chemical Industry Co., Ltd.)
(e-2a) Hisolve DB (diethylene glycol butyl ether, boiling point 230°C, SP value 21.5 (J/cm ³ ) ^1/2 ; manufactured by Toho Chemical Industry Co., Ltd.)
(e-2b) "Cerutol" (registered trademark) DPNB (dipropylene glycol butyl ether, boiling point 230°C, SP value 20.9 (J/cm ³ ) ^1/2 ; manufactured by Daicel Corporation)
(e-2c) terpineol (2-(4-methylcyclohex-3-enyl)propan-2-ol, boiling point 217° C., SP value 21.7 (J/cm ³ ) ^1/2 ; Nippon Koryo Yakuhin Co., Ltd. ) made)
(e-2d) GBL (γ-butyrolactone, boiling point 204° C., SP value 21.5 (J/cm ³ ) ^1/2 )
(e-2e) “Cerutol” DPMA (dipropylene glycol methyl ether acetate, boiling point 213° C., SP value 18.5 (J/cm ³ ) ^1/2 )
The SP value of the solvent was calculated from the molecular structure using the Fedors calculation method.

Evaluation methods in each example and comparative example are shown below.

<Adhesion in the dicing process>
On a PET film (S10 “Lumirror” (registered trademark) #125; manufactured by Toray Industries, Inc.), the photosensitive paste obtained in each example and comparative example was dried and screened so that the film thickness was 12 μm. A plurality of sheets were coated by a printing method, and each was dried in a hot air dryer at 55° C. for 10 minutes to obtain a dry film on a PET film. Each of these dried films was cut into strips having a width of 1 cm, the coated surfaces were overlapped, and a 50 g stainless steel plate was placed from above. In this state, it was heated for 1 minute with a hot air dryer heated to 85°C, 90°C, 95°C, 100°C, and 105°C. After that, the coating film surface was visually observed, and the presence or absence of adhesion was evaluated as follows.
Adhesion on the coating film surface is not observed: ○
Adhesion on the surface of the coating film is observed: ×
In this evaluation, adhesion was suppressed to the extent that no adhesion was observed on the surface of the coating film under higher temperature conditions.

<Continuous printability>
On a PET film (S10 “Lumirror” #125; manufactured by Toray Industries, Inc.), the photosensitive paste obtained in each example and comparative example was temperature-controlled for 3 minutes using a constant temperature bath at 25 ° C. Under atmospheric pressure, the viscosity was measured at a rotation speed of 10 rpm using a Brookfield viscometer (Brookfield viscometer, model HB DV-I; manufactured by Eiko Seiki Co., Ltd.).

The photosensitive pastes obtained in each example and comparative example were repeatedly applied by screen printing, and the pastes after printing 100 times, 200 times, and 500 times were collected. The viscosity of each paste was measured by the method described above, and the ratio to the viscosity before printing (viscosity after printing/viscosity before printing) was calculated. In this evaluation, the closer the viscosity ratio is to 1, the better the continuous printability.

<Fine pattern formation>
The photosensitive paste obtained in each example and comparative example was applied on a PET film (S10 Lumirror (registered trademark) #125; manufactured by Toray Industries, Inc.) by a screen printing method so that the film thickness after drying was 12 μm. A plurality of sheets were coated and each was dried in a hot air dryer at 55° C. for 10 minutes to obtain a dry film of the photosensitive paste on the PET film. The obtained dried film had a line width/space width (hereinafter, “L/S”) of the coil pattern of 25 μm/35 μm, 25 μm/28 μm, 20 μm/30 μm, 20 μm/23 μm, 15 μm/25 μm, 15 μm/18 μm. Six types of exposure masks were passed through each with a gap of 50 μm, and exposure was performed with an irradiation dose of 500 mJ/cm ² (converted to a wavelength of 365 nm) using an ultra-high pressure mercury lamp with an output of 21 mW/cm ² .

Thereafter, shower development was performed using a 0.1% by weight sodium carbonate aqueous solution as a developer until the unexposed areas were completely dissolved, thereby producing 6 types of patterned sheets with different L/S.

Six types of pattern-formed sheets with different L/S were each observed with an optical microscope at a magnification of 10 times, and the presence or absence of disconnection/short-circuiting of the pattern, and filling/residue between patterns was evaluated according to the following criteria.
No disconnection/short circuit in pattern, filling/residue between patterns: ○
Disconnection and short circuit of pattern are observed: Peeling and filling/residue between patterns are observed: Residue.

<Firing defects>
Except for applying the photosensitive paste obtained in each example and comparative example on a green sheet (GCS71F; manufactured by Yamamura Photonics Co., Ltd.), L / S by the method described in <Micro pattern formation evaluation> described above. 10 sheets each of 6 types of pattern-formed sheets with different thicknesses were produced. Ten of these pattern-formed sheets were stacked using the guide holes and press-bonded using a hydraulic press under conditions of a temperature of 90° C. and a pressure of 15 MPa to produce a ten-layer laminated sheet. The obtained 10-layer laminated sheet was heat-treated at 350° C. for 10 hours and then further heat-treated at 880° C. for 10 minutes and baked to produce a 10-layer laminated fired sheet.

A cross section of the laminated fired sheet was observed with a scanning electron microscope (S2400; manufactured by Hitachi, Ltd.) at a magnification of 500 times, and evaluated according to the following criteria.
Defects such as cracks are not observed in the layer: ○
A disconnection defect such as a crack is observed in the layer: Disconnection.

If no disconnection is observed after firing, it is possible to suppress the occurrence of defects during firing when used in electronic components, thereby improving productivity.

(Example 1)
Alkali-soluble resin (b), reactive compound (c), photoinitiator (d), and organic solvent (e) are placed in a glass flask so that the composition ratio shown in Table 1 is obtained. After stirring for hours, a photosensitive organic component solution was obtained. Inorganic powder (a) was further added to this photosensitive organic component solution so as to have the composition ratio shown in Table 1, stirred, and then kneaded using three rollers (EXAKT M-50; manufactured by EXAKT). to produce a photosensitive paste P-1. Table 8 shows the evaluation results of the obtained photosensitive paste P-1 by the method described above.

(Example 2-75, Comparative Example 1-3)
Photosensitive pastes P-2 to P-78 were obtained in the same manner as in Example 1, except that the compositions of the photosensitive pastes were changed as shown in Tables 1 to 7. Using the obtained photosensitive pastes P-2 to P-78, the evaluation results were shown in Tables 8 to 15 in the same manner as in Example 1.

(Example 76)
Photosensitive paste P-1 obtained in Example 1 was applied to a green sheet (GCS71F; manufactured by Yamamura Photonics Co., Ltd.) on which via holes had been formed by screen printing so that the film thickness after drying was 12 μm. A membrane was obtained. The resulting coating film was dried for 10 minutes using a hot air dryer at 55° C. to form a dry film P-1 on the green sheet while filling the via holes with the photosensitive paste. The dry film P-1 was exposed through an exposure mask having a coil pattern L/S of 15/18 μm with an ultra-high pressure mercury lamp with an output of 21 mW/cm ² at a dose of 500 mJ/cm ² (converted to a wavelength of 365 nm). gone. After that, shower development was carried out until the total dissolution time was reached using a 0.1% by weight sodium carbonate aqueous solution as a developer to produce a patterned sheet P-1. Ten of the pattern-formed sheets P-1 were prepared, stacked using guide holes, and pressed under conditions of a temperature of 90° C. and a pressure of 15 MPa using a hydraulic press to produce a 10-layer laminate sheet P-1. . The obtained 10-layer laminate sheet P-1 was cut into a size of 0.2 mm × 0.4 mm × 0.2 mm at a temperature of 90 ° C. using a die cutter, and after heat treatment at 350 ° C. for 10 hours. , and then fired at 880° C. for 10 minutes to produce a 10-layer laminated fired sheet P-1.

After terminal electrodes were applied to the obtained 10-layer laminated sintered sheet P-1 by sputtering, it was plated with nickel and tin to manufacture a laminated chip inductor. Copper wiring was connected to both ends of the terminal electrodes of this multilayer chip inductor by soldering, and it was confirmed by using a digital multimeter (CDM-16D; manufactured by Custom Co., Ltd.) that there was no problem in conduction.

The photosensitive paste of the present invention can be suitably used for manufacturing internal wiring patterns of electronic parts and the like.

Claims (11)

An inorganic powder (a), an alkali-soluble resin (b-1) having no photoreactive functional group and an acid value of 200 to 300 mgKOH/g, a reactive compound (c) and a photoreaction initiator (d) further comprising (b-2) an alkali-soluble resin having a photoreactive functional group , wherein the alkali-soluble resin (b-1) comprises (meth)acrylic acid/methyl (meth)acrylate/styrene copolymer , a photosensitive paste containing 20 to 40 parts by weight of the alkali-soluble resin (b-1) with respect to a total of 100 parts by weight of the alkali-soluble resin (b-1) and the alkali-soluble resin (b-2). 2. The photosensitive paste according to claim 1, wherein the alkali-soluble resin (b-1) has a weight average molecular weight (Mw) of 20,000 to 50,000. Furthermore, the SP value is 20.5 to 24.6 (J / cm ³ ) ^1/2 3. The photosensitive paste according to claim 1 or 2, which contains an organic solvent (e). The organic solvent (e) is dipropylene glycol methyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, 2-(4-methylcyclohexa-3 -enyl)propan-2-ol, propylene glycol butyl ether and/or ethylene glycol butyl ether. The organic solvent (e) comprises a low boiling point organic solvent (e-1) having a boiling point of 150°C to 200°C and a high boiling point organic solvent (e-2) having a boiling point of 201°C to 250°C. The photosensitive paste as described in 3 or 4. According to claim 5, containing 25 to 65 parts by weight of the low boiling point organic solvent (e-1) with respect to a total of 100 parts by weight of the low boiling point organic solvent (e-1) and the high boiling point organic solvent (e-2). Photosensitive paste as described. The photosensitive paste according to any one of claims 1 to 6, containing 85 to 92% by weight of the inorganic powder (a) in the total solid content. A cured film obtained by curing the photosensitive paste according to any one of claims 1 to 7. A fired body obtained by firing the cured film according to claim 8 . An electronic component comprising the fired body according to claim 9 . A method of manufacturing an electronic component, comprising the steps of applying the photosensitive paste according to any one of claims 1 to 7, drying, exposing, and developing.