Method for producing ceramic green sheet with conductive pattern

Abstract

Provided is a method for producing a ceramic green sheet with a conductive pattern, the ceramic green sheet having a highly fine conductive pattern and the occurrence of disconnection therein being suppressed. This method for producing a ceramic green sheet with a conductive pattern involves the following steps in the stated order: a step (transferring step) for preparing a base material with a photosensitive layer, and transferring the photosensitive layer on a ceramic green sheet from above the base material, wherein the photosensitive layer contains (a) conductive particles, (b) non-conductive particles, (c) an alkali-soluble resin, (d) a photosensitizing agent, and (e) a solvent and is provided on the base material, and the content of the solvent (e) is 5.0% by mass or less; a step (exposing step A) for bringing the photosensitive layer into contact with an exposure mask and exposing same; and a step (developing step) for developing the photosensitive layer after exposure to form a conductive pattern.

Description

Method for manufacturing ceramic green sheet with conductive pattern

[0001] The present invention relates to a method for producing a ceramic green sheet having a conductive pattern.

[0002] In recent years, with the demand for smaller and higher-performance electronic components, there has been a demand for higher-definition and higher-aspect ratio internal wiring. Inductors, a type of electronic component, have a coil-shaped internal electrode inside a ceramic insulator, and are generally formed by laminating multiple layers of planar ceramic insulating layers with wound internal electrodes. To achieve higher definition inductors, it is effective to use a photosensitive conductive paste that allows for finer internal electrodes. One such photosensitive conductive paste proposed is one that "contains an inorganic powder, an alkali-soluble resin that does not have a photoreactive functional group and has an acid value of 200 to 300 mg KOH / g, a reactive compound, and a photoreaction initiator" (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2019-215446

[0004] Examples of inductor manufacturing methods include forming internal electrodes on ceramic green sheets and laminating them in multiple layers, or alternately forming internal electrodes and ceramic green sheets on ceramic green sheets. The inventors' research has revealed that these methods, when a photosensitive paste as described in Patent Document 1 is directly applied to ceramic green sheets to form a pattern, result in a narrow line width at the bottom of each layer of internal electrode, making it difficult to form high-definition internal wiring. This is thought to be due to the fact that when a photosensitive paste coating is formed on a ceramic green sheet, the solvent contained in the photosensitive paste dissolves organic components contained in the ceramic green sheet, and the dissolved organic components are mixed into the photosensitive conductive paste. Furthermore, the surface of the photosensitive paste coating is sticky due to residual solvent, making it difficult to contact with an exposure mask during exposure, making it difficult to form high-definition internal wiring. Furthermore, a large amount of solvent erodes the surface of the ceramic green sheet, making it difficult to form internal electrodes and increasing the risk of breakage due to micro-defects. On the other hand, one way to suppress the effects of the solvent is to form a photosensitive paste coating on a ceramic green sheet and then quickly dry and remove the solvent at high temperature. However, when the photosensitive paste coating is dried at high temperature on the ceramic green sheet, the ceramic green sheet shrinks due to the heat, making it difficult to form high-definition internal wiring.

[0005] Therefore, an object of the present invention is to provide a method for producing a ceramic green sheet having a conductive pattern with high-definition conductive patterns that suppresses the occurrence of disconnections.

[0006] In order to solve the above problems, the present invention mainly has the following configuration: (1) A method for producing a ceramic green sheet having a conductive pattern, the method comprising the steps of: preparing a substrate having a photosensitive layer on the substrate, the photosensitive layer containing conductive particles (a), non-conductive particles (b), an alkali-soluble resin (c), a photosensitizer (d), and a solvent (e), with the content of the solvent (e) being 5.0 mass % or less; transferring the photosensitive layer from the substrate to a ceramic green sheet (transfer step); exposing the photosensitive layer by bringing an exposure mask into contact with the photosensitive layer (exposure step A); and developing the exposed photosensitive layer to form a conductive pattern (development step). (2) A method for producing a ceramic green sheet having a conductive pattern, the method comprising the steps of: preparing a substrate with a photosensitive layer on a substrate, the photosensitive layer containing conductive particles (a), non-conductive particles (b), an alkali-soluble resin (c), a photosensitizer (d), and a solvent (e), the content of the solvent (e) being 5.0 mass% or less; and laminating the substrate with the photosensitive layer on the ceramic green sheet so that the photosensitive layer is in contact with the ceramic green sheet (laminating step); exposing the substrate with the photosensitive layer by contacting an exposure mask with the substrate (exposing step B); and developing the exposed photosensitive layer to form a conductive pattern (developing step). (3) A method for producing a ceramic green sheet having a conductive pattern according to (1) or (2), wherein the content of the solvent (e) in the photosensitive layer is 0.1 mass% or more. (4) The method for producing a ceramic green sheet having a conductive pattern according to any one of (1) to (3), wherein the alkali-soluble resin (c) contains a carboxyl group-containing resin having no unsaturated double bond and has a glass transition temperature of 110° C. or lower. (5) The method for producing a ceramic green sheet having a conductive pattern according to (4), wherein the alkali-soluble resin (c) has a glass transition temperature of 30° C. or higher and 70° C. or lower. (6) The method for producing a ceramic green sheet having a conductive pattern according to any one of (1) to (5), wherein the photosensitive layer contains polyether-modified polydimethylsiloxane.(7) A method for producing a ceramic green sheet having a conductive pattern according to any one of (1) to (6), further comprising the step of applying a photosensitive paste containing conductive particles (a), non-conductive particles (b), an alkali-soluble resin (c), a photosensitizer (d), and a solvent (e) onto a substrate by screen printing, and drying the paste to form a photosensitive layer, thereby obtaining the substrate with the photosensitive layer. (8) A method for producing a ceramic green sheet having a conductive pattern according to any one of (1) to (7), wherein the solvent (e) includes a solvent having a boiling point of 150 to 300°C under atmospheric pressure. (9) A method for producing a ceramic green sheet having a conductive pattern according to any one of (1) to (8), wherein the photosensitive layer has a thickness of more than 10 μm and not more than 25 μm. (10) A method for producing a ceramic green sheet having a conductive pattern according to any one of (1) to (9), wherein the ceramic green sheet contains a photosensitive organic component. (11) A method for manufacturing a laminate formed by stacking a plurality of ceramic green sheets with a conductive pattern, comprising the steps of: forming a first conductive pattern by the method for manufacturing a ceramic green sheet with a conductive pattern according to any one of (1) to (10) to obtain a ceramic green sheet with a conductive pattern; forming a ceramic green sheet on the conductive pattern side of the first ceramic green sheet with a conductive pattern; and forming a second conductive pattern on the ceramic green sheet on which the first ceramic green sheet with a conductive pattern has been formed by the method for manufacturing a ceramic green sheet with a conductive pattern according to any one of (1) to (10). (12) A method for manufacturing a laminate formed by stacking a plurality of ceramic green sheets with a conductive pattern, comprising the steps of: obtaining a plurality of ceramic green sheets with a conductive pattern by the method for manufacturing a ceramic green sheet with a conductive pattern according to any one of (1) to (10); and stacking and thermocompression bonding the plurality of ceramic green sheets with a conductive pattern. (13) A method for producing a sintered body, comprising the steps of obtaining a ceramic green sheet with a conductive pattern by the production method according to any one of (1) to (10), and firing the obtained ceramic green sheet with a conductive pattern.

[0007] According to the present invention, it is possible to obtain a ceramic green sheet having a highly precise conductive pattern in which the occurrence of disconnection is suppressed.

[0008] FIG. 2 is a schematic diagram of a mask pattern of an exposure mask used in the examples.

[0009] The ceramic green sheet with a conductive pattern of the present invention has ceramic green sheets and conductive patterns on a substrate. For example, when used in an inductor, a plurality of such layers are laminated and fired, whereby the ceramic green sheets form insulating layers and the conductive patterns form internal electrodes.

[0010] The method for producing a ceramic green sheet with a conductive pattern of the present invention comprises, in this order, a transfer step or lamination step, an exposure step, and a development step, as described below. Instead of directly applying a photosensitive paste onto the ceramic green sheet, a photosensitive layer containing a solvent in advance within a predetermined range is laminated onto the ceramic green sheet by the transfer step or lamination step. This suppresses the adhesiveness of the photosensitive layer and thinning of the bottom of the conductive pattern caused by the solvent (e), allowing the formation of a high-resolution pattern and preventing breakage. Furthermore, since high-temperature drying of the ceramic green sheet is not required, shrinkage of the ceramic green sheet due to heat is suppressed, allowing the formation of a high-resolution pattern.

[0011] A first aspect of the method for producing a ceramic green sheet with a conductive pattern of the present invention includes the following steps, in order: preparing a substrate with a photosensitive layer on the substrate, the photosensitive layer containing conductive particles (a), non-conductive particles (b), an alkali-soluble resin (c), a photosensitizer (d), and a solvent (e), with the solvent (e) content being 5.0 mass% or less; transferring the photosensitive layer from the substrate to a ceramic green sheet (transfer step); exposing the photosensitive layer by contacting an exposure mask with the photosensitive layer (exposure step A); and developing the exposed photosensitive layer to form a conductive pattern (development step). In the transfer step, the photosensitive layer is exposed on the surface so that it can be transferred to the ceramic green sheet. In the exposure step A, contact exposure is possible by contacting the photosensitive layer with the exposure mask. This allows for the formation of a finer pattern.

[0012] A second aspect of the method for producing a ceramic green sheet with a conductive pattern of the present invention includes the following steps, in this order: preparing a substrate with a photosensitive layer on a substrate, the photosensitive layer containing conductive particles (a), non-conductive particles (b), an alkali-soluble resin (c), a photosensitizer (d), and a solvent (e), with the solvent (e) content being 5.0 mass% or less; laminating the substrate with the photosensitive layer on the ceramic green sheet so that the photosensitive layer is in contact with the ceramic green sheet (laminating step); exposing the substrate with the photosensitive layer by contacting an exposure mask with the substrate (exposure step B); and developing the exposed photosensitive layer to form a conductive pattern (developing step). In the laminating step, the substrate is present on the photosensitive layer, and the photosensitive layer is exposed through the substrate in exposure step B. Because the photosensitive layer is protected by the substrate, breaks in the conductive pattern can be further suppressed.

[0013] The substrate with a photosensitive layer used in the present invention can be obtained, for example, by applying a photosensitive paste containing conductive particles (a), non-conductive particles (b), an alkali-soluble resin (c), a photosensitizer (d) and a solvent (e) onto a substrate by a screen printing method, and drying the paste to form a photosensitive layer.

[0014] Substrate Examples of the substrate include a metal substrate, a glass substrate, and a plastic film. Among these, from the viewpoint of the releasability of the photosensitive layer and the light transmittance of the exposure light in the exposure step B when used in the second embodiment, plastic films containing resins such as polyethylene terephthalate (PET), cycloolefin polymers, polycarbonates, polyimides, aramids, fluororesins, acrylic resins, and polyurethane resins are preferred, and films containing PET, cycloolefin polymers, and polycarbonates are more preferred. From the viewpoint of improving the releasability of the photosensitive layer, it is preferred that one or both sides of the plastic film be subjected to a release treatment using a silicone resin, a fluororesin, or the like.

[0015] The thickness of the substrate is preferably 10 μm or more, more preferably 20 μm or more, from the viewpoint of ease of handling, while it is preferably 200 μm or less, more preferably 100 μm or less, and even more preferably 75 μm or less, from the viewpoints of the thickness of the substrate, the ability to follow the ceramic green sheet in the transfer step or lamination step, and reducing the gap between the exposure mask and the photosensitive layer in the exposure step B when used in the second embodiment.

[0016] Conductive particles (a) In the present invention, the conductive particles (a) have a specific resistance of 1.0 × 10 at 20 ° C. －４ The conductive particles (a) refer to particles having a resistance of Ω·m or less, and have the effect of imparting conductivity to the conductive pattern upon firing. Examples of conductive particles (a) include particles of metals such as silver, gold, copper, platinum, palladium, tin, nickel, aluminum, tungsten, molybdenum, ruthenium, chromium, titanium, and indium, as well as alloys thereof, carbon, titanium nitride, and the like. Two or more of these may be contained. Among these, silver, copper, and gold particles are preferred from the viewpoint of conductivity, and silver particles are more preferred from the viewpoint of stability.

[0017] The median diameter (D50) of the conductive particles (a) is preferably 1 μm or more from the viewpoint of improving conductivity. On the other hand, the D50 of the conductive particles (a) is preferably 5 μm or less from the viewpoint of improving the light transmittance of the exposure light and forming a finer pattern. The D50 of the conductive particles (a) can be measured by a laser light scattering method using a particle size distribution analyzer (Microtrac HRA Model No. 9320-X100; manufactured by Nikkiso Co., Ltd.).

[0018] The content of the conductive particles (a) in the photosensitive paste is preferably 60% by mass or more, more preferably 65% ​​by mass or more, and even more preferably 70% by mass or more from the viewpoint of electrical conductivity, while the content of the conductive particles (a) is preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less from the viewpoint of optical transparency of the exposure light.

[0019] Non-conductive particles (b) Non-conductive particles (b) have a specific resistance of 1.0 × 10 at 20 °C. －４ These particles have a resistance exceeding Ω·m or are insulating, and have the effect of suppressing the shrinkage of conductive patterns during firing.

[0020] The non-conductive particles (b) may be, for example, alumina (Al ２ O ３ ), zirconia (ZrO ２ ), magnesia (MgO), beryllia (BeO), mullite (3Al ２ O ３ 2SiO ２ ), cordierite (5SiO ２ ・2Al ２ O ３ ・2MgO), spinel (MgO・Al ２ O ３ ), forsterite (2MgO.SiO ２ ), anorthite (CaO·Al ２ O ３ 2SiO ２ ), Celsius (BaO·Al ２ O ３ 2SiO ２ ), silica (SiO ２ ), barium titanate (BaTiO ３, aluminum nitride (AlN), ferrite (garnet type: Y ３ FeO １２ System, spinel type: MeFe ２ O ４ system), “SiO ２ , Al ２ O ３ , CaO, B ２ O ３ , MgO, TiO ２ ", etc. Two or more of these may be contained. Among these, from the viewpoint of further suppressing firing defects, particles of titania, alumina, silica, cordierite, mullite, spinel, barium titanate, and zirconia are preferred, and silica particles are more preferred.

[0021] From the viewpoint of suppressing shrinkage of the conductive pattern during firing, the D50 of the non-conductive particles (b) is preferably 5 μm or less, more preferably 0.1 μm or less, and even more preferably 0.05 μm or less. When the D50 of the non-conductive particles (b) is 0.1 μm or less, the D50 can be determined by adding the non-conductive particles (b) to water, subjecting the non-conductive particles (b) to ultrasonic treatment for 300 seconds, and then using a Nanotrac Wave II-UZ251 (manufactured by Microtrac BEL) by dynamic light scattering.

[0022] The content of the non-conductive particles (b) in the photosensitive paste is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.4% by mass or more, from the viewpoint of suppressing shrinkage of the conductive pattern during firing. On the other hand, the content of the non-conductive particles (b) is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 2% by mass or less, from the viewpoint of conductivity.

[0023] Alkali-Soluble Resin (c) The alkali-soluble resin (c) refers to a resin having a carboxyl group and / or a hydroxyl group on the side chain, and serves as a binder resin for the photosensitive paste, and also has the effect of dissolving during development to form a pattern.

[0024] The alkali-soluble resin (c) is preferably an acrylic resin, and more preferably a copolymer of an acrylic monomer having a carbon-carbon double bond and another monomer. Examples of the acrylic monomer having a carbon-carbon double bond and the other monomer include those exemplified as raw materials for the acrylic resin, which is an example of the alkali-soluble resin (b-1), in JP 2019-215446 A.

[0025] The alkali-soluble resin (c) preferably has a carbon-carbon double bond in the side chain and / or molecular terminal, which can improve the curing reaction rate during exposure. Examples of structures having a carbon-carbon double bond include a vinyl group, an allyl group, an acrylic group, and a methacrylic group. Two or more of these may be present. In the case of an acrylic resin, a method for introducing a carbon-carbon double bond into the alkali-soluble resin (c) includes, for example, reacting a mercapto group, an amino group, a hydroxyl group, or a carboxyl group in the acrylic resin with a compound having a glycidyl group or an isocyanate group and a carbon-carbon double bond, acrylic acid chloride, methacrylic acid chloride, allyl chloride, or the like.

[0026] Examples of compounds having a glycidyl group and a carbon-carbon double bond include glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, glycidyl crotonate, glycidyl isocrotonate, and Cyclomer (registered trademark) M100 and A200 (all manufactured by Daicel Chemical Industries, Ltd.). Examples of compounds having an isocyanate group and a carbon-carbon double bond include acryloyl isocyanate, methacryloyl isocyanate, acryloylethyl isocyanate, and methacryloylethyl isocyanate. Two or more of these may be used.

[0027] A preferred example of the alkali-soluble resin (c) is one containing a carboxyl group-containing resin that does not have an unsaturated double bond. Examples of carboxyl group-containing resins having no unsaturated double bonds include solid JONCRYL67 (glass transition temperature 73°C), JONCRYL678 (glass transition temperature 85°C), JONCRYL611 (glass transition temperature 50°C), JONCRYL693 (glass transition temperature 84°C), JONCRYL682 (glass transition temperature 56°C), JONCRYL690 (glass transition temperature 102°C), JONCRYL819 (glass transition temperature 57°C), JONCRYLJDX-C3000A (glass transition temperature 65°C), and JONCRYLJDX-C3080 (glass transition temperature 134°C), manufactured by BASF Japan Ltd.; JONCRYLJDX-6157 (glass transition temperature 84°C), JONCRYL60J (glass transition temperature 85°C), JONCRYL63J (glass transition temperature 73°C), JONCRYL70J (glass transition temperature 102°C), JONCRYLJDX-6180 (glass transition temperature 134°C), JONCRYLHPD-196 (glass transition temperature 85°C), JONCRYLHPD-96J (glass transition temperature 102°C), JONCRYLPDX-6137A (glass transition temperature 102°C), JONCRYL6610 (glass transition temperature 85°C), JONCRYLJDX-6500 (glass transition temperature 65°C), and JONCRYLPDX-6102B (glass transition temperature 19°C). Two or more of these may be used.

[0028] From the viewpoint of improving transferability, the glass transition temperature of the carboxyl group-containing resin having no unsaturated double bond is preferably 110°C or lower, and more preferably 30 to 70°C.

[0029] The content of the alkali-soluble resin (c) in the photosensitive paste is preferably 1 to 10% by mass from the viewpoints of photolithography processability, viscosity characteristics, and the like.

[0030] Photosensitizer (d) Examples of the photosensitizer (d) include photopolymerization initiators, dissolution inhibitors, etc. From the viewpoint of forming a thicker conductive pattern, photopolymerization initiators are preferred.

[0031] Photopolymerization initiators absorb short wavelength light such as ultraviolet light and decompose, or generate radicals through a hydrogen abstraction reaction, thereby imparting photocurability and enabling pattern formation by negative photolithography. Examples of photopolymerization initiators include those exemplified as photoreaction initiator (d) in JP 2019-215446 A. From the viewpoint of photocurability, oxime-based photopolymerization initiators are preferred.

[0032] The dissolution inhibitor increases the solubility of the exposed portion in the developer, enabling pattern formation by positive photolithography. Dissolution inhibitors that generate acid upon exposure to the exposure energy used in the exposure step described below are preferred. Examples of dissolution inhibitors include diazodisulfone compounds, triphenylsulfonium compounds, and quinone diazide compounds. Examples of diazodisulfone compounds include bis(cyclohexylsulfonyl)diazomethane, bis(tert-butylsulfonyl)diazomethane, and bis(4-methylphenylsulfonyl)diazomethane. Examples of triphenylsulfonium compounds include diphenyl-4-methylphenylsulfonium trifluoromethanesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium p-toluenesulfonate, and diphenyl(4-methoxyphenyl)sulfonium trifluoromethanesulfonate. Examples of the quinone diazide compound include a compound in which the sulfonic acid of quinone diazide is bonded to a polyhydroxy compound via an ester bond, a compound in which the sulfonic acid of quinone diazide is bonded to a polyamino compound via a sulfonamide bond, and a compound in which the sulfonic acid of quinone diazide is bonded to a polyhydroxypolyamino compound via an ester bond and / or a sulfonamide bond. Two or more of these compounds may be used.

[0033] The content of the photosensitizer (d) in the photosensitive paste is preferably 0.1 to 2% by mass.

[0034] Solvent (e) The solvent (e) has the effect of adjusting the viscosity of the photosensitive paste. The boiling point of the solvent (e) under atmospheric pressure is preferably 150°C or higher from the viewpoint of improving the coatability when the photosensitive paste is continuously applied, improving the peelability from the substrate, and improving the transferability. On the other hand, the boiling point of the solvent (e) under atmospheric pressure is preferably 300°C or lower from the viewpoint of drying and removability. Examples of solvents having a boiling point within the above range include ethylene glycol hexyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol n-butyl ether, diethylene glycol ethyl ether, diethylene glycol diethyl ether, diethylene glycol butyl methyl ether, diethylene glycol methyl ether, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol monomethyl ether, dipropylene glycol n-butyl ether, dipropylene glycol propyl ether, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether, dipropylene glycol methyl ether acetate, dipropylene glycol Examples of suitable ethylene glycol copolymers include 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, diethylene glycol hexyl ether, diethylene glycol mono-2-ethylhexyl ether, diethylene glycol monohexyl ether, dipropylene glycol phenyl ether, tetraethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, triethylene glycol monobutyl ether, tripropylene glycol butyl ether, tripropylene glycol monobutyl ether, and diethylene glycol dibutyl ether. Two or more of these may be contained.

[0035] The content of the solvent (e) in the photosensitive paste is preferably 5 to 40% by mass from the viewpoint of the viscosity of the paste.

[0036] It is preferable that the photosensitive paste of the present invention contains a leveling agent, which has the effects of suppressing repellency when the photosensitive paste is applied to a substrate and improving the releasability of the photosensitive layer.

[0037] Examples of leveling agents include anionic surfactants such as ammonium lauryl sulfate and polyoxyethylene alkyl ether triethanolamine sulfate; cationic surfactants such as stearylamine acetate and lauryl trimethylammonium chloride; amphoteric surfactants such as lauryl dimethylamine oxide and lauryl carboxymethyl hydroxyethyl imidazolium betaine; nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and sorbitan monostearate; silicone surfactants having a main skeleton such as polydimethylsiloxane or polymethylalkylsiloxane; fluorine-based surfactants; and acrylic surfactants. The polymethylalkylsiloxane may be an arachyl-modified polymethylalkylsiloxane. Among these, silicone surfactants having a main skeleton such as polydimethylsiloxane or acrylic surfactants are preferred. Furthermore, it is more preferred that the photosensitive layer in the present invention contains polyether-modified polydimethylsiloxane as the silicone surfactant having a main skeleton such as polydimethylsiloxane.

[0038] The photosensitive paste of the present invention may also contain additives such as a photopolymerizable compound having an unsaturated bond, a plasticizer, a leveling agent, a dispersant, a surfactant, a silane coupling agent, an antifoaming agent, a pigment, or a dye, within a range that does not impair the desired properties.

[0039] The photosensitive paste of the present invention can be obtained, for example, by dissolving and / or dispersing the above-mentioned components (a) to (d) and, if necessary, other additives, in a solvent (e). Examples of devices for dissolving and / or dispersing include dispersers and kneaders such as triple rollers and ball mills. Dissolving and / or dispersing may be performed at room temperature or under heating.

[0040] Next, the photosensitive paste is applied onto the substrate and dried to form a photosensitive layer.

[0041] Examples of the coating method include spray coating, roll coating, screen printing, and coating methods using a blade coater, die coater, calendar coater, meniscus coater, bar coater, etc. Among these, screen printing is preferred from the viewpoints of suitability for thick film coating, continuous productivity, etc.

[0042] Examples of the drying method include heat drying using a heating device such as an oven, a hot plate, or infrared drying, vacuum drying, etc. The heating temperature is preferably 40 to 100° C., and it is preferable to select conditions such as the heating device, drying temperature, and drying time so that the content of the solvent (e) in the photosensitive layer is 5.0 mass % or less.

[0043] In the present invention, the content of solvent (e) in the photosensitive layer is preferably 5.0% by mass or less. As described above, by transferring or laminating such a photosensitive layer onto a ceramic green sheet, the adhesiveness of the photosensitive layer and thinning of the bottom of the conductive pattern caused by solvent (e) are suppressed, thereby enabling the formation of a high-resolution pattern and preventing wire breakage. Furthermore, since high-temperature drying on the ceramic green sheet is not required, heat-induced shrinkage of the ceramic green sheet is suppressed, allowing the formation of a high-resolution pattern. If the content of solvent (e) exceeds 5.0% by mass, the adhesiveness of the photosensitive layer and thinning of the bottom of the conductive pattern may make it difficult to form a high-resolution pattern. Furthermore, wire breakage may occur more easily. The content of solvent (e) is preferably 2.0% by mass or less, which can further improve line width uniformity. On the other hand, the content of solvent (e) in the photosensitive layer is preferably 0.10% by mass or more, which can improve releasability from the substrate and transferability.

[0044] The thickness of the photosensitive layer in the substrate with the photosensitive layer is preferably more than 10 μm, which can prevent disconnection of the conductive pattern, while the thickness of the photosensitive layer is preferably 25 μm or less, which allows the exposure light to easily penetrate deep into the photosensitive layer in the exposure step described below, thereby enabling the formation of a more precise pattern.

[0045] Next, each step of the method for producing a ceramic green sheet having a conductive pattern according to the first embodiment of the present invention will be described.

[0046] (Transfer Step) The substrate with the photosensitive layer described above is prepared, and the photosensitive layer is transferred from the substrate to a ceramic green sheet. The photosensitive layer may be peeled off from the substrate and then laminated on the ceramic green sheet, or the substrate with the photosensitive layer may be laminated on the ceramic green sheet so that the photosensitive layer is in contact with the ceramic green sheet, and then the substrate may be peeled off. In either method, transfer is preferably performed by pressure bonding, and examples of transfer devices include a press and a roll laminator. The transfer temperature is preferably 20°C to 200°C. The transfer pressure is preferably 0.1 MPa to 2.0 MPa. The pressure application time is preferably 10 to 300 seconds. Examples of the atmosphere include air, nitrogen, and vacuum.

[0047] Examples of ceramic green sheets include sheets of insulating compositions containing inorganic powders such as glass, ceramic, and glass ceramic, and binder resins. The ceramic green sheets also preferably contain a photosensitive organic component, which can impart photosensitivity. In this case, the insulating composition preferably contains a photosensitive organic component. Furthermore, a sheet of the insulating composition may be provided on a substrate, such as a plastic film or optical resin plate, which are exemplified as the substrate for the photosensitive layer-attached substrate. The ceramic green sheets can be obtained, for example, by applying an insulating composition prepared by dispersing the inorganic powder in a binder resin to a substrate, such as a plastic film or optical resin plate, to form a paste. Examples of application methods include those exemplified as the methods for applying the photosensitive paste. When the ceramic green sheets are photosensitive, patterns may be formed by photolithography.

[0048] Examples of the photosensitive organic component include the alkali-soluble resin (c), the photosensitizer (d), and the photopolymerizable compound having an unsaturated bond, which are given as examples of the raw materials for the conductive paste.

[0049] (Exposure Step A) The photosensitive layer is exposed by contacting an exposure mask. Eliminating the gap between the exposure mask and the photosensitive layer suppresses the spread of exposure light due to diffraction and line thickening due to the influence of reflection of the exposure light on the surface of the photosensitive layer and the exposure mask, allowing for the formation of a more precise pattern. Furthermore, the uniformity of the pattern line width is improved. Examples of actinic rays used for exposure include ultraviolet light, visible light, electron beams, and X-rays. In the present invention, the i-line (wavelength 365 nm), h-line (wavelength 405 nm), and g-line (wavelength 436 nm) of a mercury lamp are preferred.

[0050] (Developing Step) The exposed photosensitive layer is developed to form a conductive pattern.

[0051] The developer is preferably an alkaline developer, and examples thereof include those exemplified as developers for use in alkaline development in JP-A-2019-215446.

[0052] Examples of the developing method include a method in which a developer is sprayed onto the ceramic green sheet having the photosensitive layer after exposure while the sheet is left standing, transported, or rotated; a method in which the ceramic green sheet having the photosensitive layer after exposure is immersed in a developer; and a method in which ultrasonic waves are applied to the ceramic green sheet having the photosensitive layer after exposure while the ceramic green sheet is immersed in a developer.

[0053] The pattern obtained by development may be subjected to a rinse treatment with a rinse liquid. Examples of the rinse liquid include those exemplified as rinse liquids in JP-A-2019-215446.

[0054] Furthermore, if necessary, a step of drying the remaining solvent or developer in the photosensitive layer (drying step) may be included. By drying and removing the remaining solvent or developer, the shrinkage rate can be reduced when producing a fired body, which will be described later. Examples of drying methods include the methods exemplified as drying methods for forming the photosensitive layer.

[0055] Next, a second embodiment of the method for producing a ceramic green sheet having a conductive pattern according to the present invention will be described.

[0056] (Laminating step) The above-described substrate with a photosensitive layer is prepared, and the substrate with a photosensitive layer is laminated on the ceramic green sheet so that the photosensitive layer is in contact with the ceramic green sheet. In the laminating step, it is not necessary to peel off the substrate from the substrate with a photosensitive layer. The rest is the same as in the (transferring step) in the first embodiment.

[0057] (Exposure step B) The substrate with a photosensitive layer is exposed by contacting an exposure mask with the substrate. By contacting the exposure mask with the substrate, the gap between the exposure mask and the photosensitive layer can be kept constant, improving the uniformity of the pattern line width. In addition, since the exposure mask and the photosensitive layer are not in direct contact, damage to the photosensitive layer can be suppressed, and disconnection of the conductive pattern can be further suppressed. Except for peeling off the substrate after exposure, the other steps are the same as those in (Exposure step A) of the first embodiment.

[0058] The (developing step) and (laminating step) are the same as in the first embodiment, and a drying step may be further included.

[0059] The ceramic green sheet with a conductive pattern of the present invention can be used as a laminate by stacking multiple layers. By stacking, the thickness of the conductive pattern can be increased. The number of layers is preferably 2 to 30. By limiting the number of layers to 30 or less, the influence of misalignment between layers can be suppressed.

[0060] A first aspect of the method for producing a laminate of the present invention preferably comprises the steps of: forming a first conductive pattern by the above-described method to obtain a ceramic green sheet with a conductive pattern; forming a ceramic green sheet on the conductive pattern side of the ceramic green sheet with the first conductive pattern; and forming a second conductive pattern by the above-described method on the ceramic green sheet on which the first ceramic green sheet with the conductive pattern has been formed.

[0061] A second aspect of the method for producing a laminate of the present invention preferably includes the steps of: obtaining a plurality of ceramic green sheets with conductive patterns by the above-described method; and laminating and thermocompression bonding the plurality of ceramic green sheets with conductive patterns. Examples of the lamination method include stacking ceramic green sheets using guide holes. Examples of the thermocompression bonding device include a hydraulic press. The thermocompression bonding temperature is preferably 90 to 130°C, and the thermocompression bonding pressure is preferably 5 to 20 MPa.

[0062] The ceramic green sheet or laminate with a conductive pattern of the present invention can be fired to be used as a fired body. The thickness of the fired body is preferably 2 μm or more from the viewpoint of suppressing disconnection during firing. On the other hand, the thickness of the fired body is preferably 20 μm from the viewpoint of suppressing swelling during firing. Furthermore, the line width of the conductive pattern in the fired body is preferably 5 μm or more from the viewpoint of suppressing disconnection during firing. On the other hand, the line width of the conductive pattern in the fired body is preferably 40 μm or less from the viewpoint of improving the aspect ratio.

[0063] The method for producing a sintered body of the present invention preferably includes the steps of: obtaining a ceramic green sheet or a laminate thereof with a conductive pattern by the above-described production method; and firing the obtained ceramic green sheet or laminate thereof. Examples of the firing method include a method in which the sheet is heat-treated at 300 to 600°C for 5 minutes to several hours, and then further heat-treated at 850 to 900°C for 5 minutes to several hours.

[0064] As an example of the method for producing the sintered body of the present invention, a method for producing a multilayer chip inductor will be described below.

[0065] First, a first conductive pattern is formed by the method for producing a ceramic green sheet with a conductive pattern of the present invention to obtain a ceramic green sheet with a conductive pattern. Next, a ceramic green sheet is formed on the conductive pattern side of the first ceramic green sheet with a conductive pattern. Via holes are then formed in the formed ceramic green sheet, and conductors are embedded in the via holes to form interlayer connection wiring. Examples of via hole formation methods include laser irradiation. When the ceramic green sheet is photosensitive, vias can be formed with high precision by exposing and developing through a mask with a via shape. Examples of methods for forming interlayer connection wiring include embedding a conductive paste by screen printing and drying. Examples of conductive pastes include pastes containing copper, silver, or a silver-palladium alloy. Next, a second conductive pattern is formed on the ceramic green sheet with the conductive pattern formed thereon by the production method of the present invention. These processes can be repeated to obtain a laminate. Alternatively, a laminate can be obtained by preparing multiple ceramic green sheets with a conductive pattern of the present invention, stacking them, and thermocompression bonding them.

[0066] The resulting laminate is diced into a desired chip size, fired, coated with terminal electrodes, and plated to obtain a multilayer chip inductor. Examples of these methods include the method exemplified in JP 2019-215446 A as a method for manufacturing a multilayer chip inductor.

[0067] The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to these.

[0068] The materials used in each of the examples and comparative examples are as follows.

[0069] Conductive particles (a): particle size (D50) 2.1 μm, specific resistance 1.6×10 －８ Ω·m Ag particles (hereinafter referred to as Ag particles). The particle size (D50) of the conductive particles was measured by a laser light scattering method using a particle size distribution measuring device (Microtrac HRA Model No. 9320-X100; manufactured by Nikkiso Co., Ltd.).

[0070] Non-conductive particles (b): Particle size (D50) 12 nm, insulating silica powder "AEROSIL (registered trademark)" R972 (manufactured by Nippon Aerosil Co., Ltd.) (hereinafter referred to as Aerosil R972). The particle size (D50) of the non-conductive particles was measured by dynamic light scattering using a Nanotrac Wave II-UZ251 (manufactured by Microtrac BEL) after adding the non-conductive particles to water and subjecting them to ultrasonic treatment for 300 seconds.

[0071] Alkali-soluble resin (c): c-1: A carboxyl group-containing acrylic copolymer (c-1) was obtained by addition reaction of 40 mole parts of glycidyl methacrylate with 100 mole parts of carboxyl groups in a copolymer of methacrylic acid / methyl methacrylate / styrene (molar ratio: 54 / 23 / 23) (containing unsaturated double bonds, weight-average molecular weight: 30,000, glass transition temperature: 110°C).

[0072] c-2: JONCRYL690 (no unsaturated double bonds, weight average molecular weight 16,500, glass transition temperature 102°C; manufactured by BASF Japan Ltd.).

[0073] c-3: JONCRYL819 (no unsaturated double bonds, weight average molecular weight 14,500, glass transition temperature 57°C; manufactured by BASF Japan Ltd.).

[0074] Photosensitizer (d): Oxime-based photopolymerization initiator "OPTOMER (registered trademark)" N-1919 (manufactured by ADEKA Corporation) (hereinafter referred to as N-1919).

[0075] Solvent (e): e-1: Cyclohexanol acetate "Cellul (registered trademark)" CHXA (manufactured by Daicel Corporation, boiling point at atmospheric pressure: 173°C).

[0076] e-2: Propylene glycol monomethyl ether acetate (boiling point at atmospheric pressure: 146°C).

[0077] Photosensitive monomer: ester structure-containing urethane acrylate NK Oligo UA-122P (viscosity 7.0 Pa·s, weight average molecular weight 1,100, manufactured by Shin-Nakamura Chemical Co., Ltd.) (hereinafter referred to as UA-122P).

[0078] Leveling agent: "Disparlon (registered trademark)" L-1980N (manufactured by Kusumoto Chemicals Co., Ltd.) (hereinafter referred to as L-1980N).

[0079] Dispersant: FLORENE G-700 (manufactured by Kyoeisha Chemical Co., Ltd.) (hereinafter referred to as G-700).

[0080] <Production of Substrate with Ceramic Green Sheet> 250 g of ceramic powder "PARCERAM (registered trademark)" BT149 (manufactured by Nippon Chemical Industry Co., Ltd.), 240 g of the above-mentioned alkali-soluble resin (c), 80 g of dibutyl phthalate as a plasticizer, 30 g of "IRGACURE (registered trademark)" 651 (manufactured by BASF) as a photopolymerization initiator, and 160 g of ethylene glycol monobutyl ether as a solvent were weighed out, mixed, and kneaded using three rollers to obtain a composition.

[0081] The resulting composition was applied to a PET film having a thickness of 100 μm and dried to prepare a substrate with a ceramic green sheet.

[0082] The evaluation methods used in each of the examples and comparative examples are shown below.

[0083] <Thickness of Photosensitive Layer> The thickness of the photosensitive layer prepared in each of the Examples and Comparative Examples was measured using a stylus-type step gauge ("Surfcom (registered trademark)" 1400; manufactured by Tokyo Seimitsu Co., Ltd.).

[0084] <Solvent Content in Photosensitive Layer> The photosensitive layer alone was peeled from the substrate with the photosensitive layer prepared in each Example and Comparative Example, and its weight was measured. It was then heated at 100°C for 3 hours in a hot air oven, and the weight was measured again. The change in weight before and after heating was calculated, and the solvent content in the photosensitive layer was calculated from the ratio (%) of the weight of the photosensitive layer before heating. Solvent content [wt %] = {(weight of photosensitive layer before heating [g] - weight of photosensitive layer after heating [g]) ÷ (weight of photosensitive layer before heating) [g]} × 100.

[0085] <Transferability> In the transfer step or lamination step of each of the Examples and Comparative Examples, the transfer step and lamination step were performed under low temperature and low pressure conditions within the range of conditions of a thermocompression temperature of 50 to 130°C, a thermocompression pressure of 0.1 to 0.3 MPa, and a thermocompression time of 30 seconds (fixed). After peeling the substrate from the photosensitive layer, the surface of the substrate was visually observed. Transferability was evaluated based on the condition under which no remaining photosensitive layer was observed on the substrate.

[0086] <Fine Pattern Processability> For the ceramic green sheets with conductive patterns obtained in each of the Examples and Comparative Examples, the conductive pattern portions were observed at a magnification of 1,000 times using an optical microscope, and the minimum line width at which breakage and peeling were not observed was determined.

[0087] Furthermore, for the ceramic green sheets with conductive patterns obtained in each example and comparative example, conductive patterns corresponding to an exposure mask opening width of 15 μm were cut in the line width direction, and the cross sections of the patterns were observed at a magnification of 3,000 times using a scanning electron microscope (S2400; manufactured by Hitachi, Ltd.), and the top and bottom widths of the conductive patterns were measured, and the difference between the top and bottom widths was calculated.

[0088] <Line width uniformity> For the ceramic green sheets with conductive patterns for evaluating line width uniformity obtained in each of the Examples and Comparative Examples, the conductive patterns corresponding to an exposure mask opening width of 15 μm in each of the 25 blocks were magnified 1,000 times using an optical microscope, the line widths of the upper parts of the conductive patterns were measured, and the difference between the maximum and minimum values ​​was calculated.

[0089] <Probability of Disconnection> One hundred ceramic green sheets with conductive patterns for evaluating the probability of disconnection obtained in each Example and Comparative Example were fired at 880°C for 10 minutes to obtain fired bodies. The resistance values ​​of the resulting fired bodies were measured using a digital multimeter (CDM-16D; manufactured by Custom Co.), and cases where the resistance value could not be measured were judged to have been disconnected. The percentage (%) of samples in which disconnection occurred among 100 fired bodies was taken as the probability of disconnection.

[0090] Example 1 Preparation of Photosensitive Paste 14.8 g of c-1, 2.0 g of N-1919, 60.0 g of e-1, 7.5 g of UA-122P, 0.4 g of L-1980N, and 0.4 g of G-700 were placed in a 200 mL clean bottle and mixed using a planetary centrifugal vacuum mixer "Awatori Rentaro (registered trademark)" ARE-310 (manufactured by Thinky Corporation) to obtain 85.1 g of a resin solution. The obtained resin solution was mixed with 248.1 g of Ag particles and 1.6 g of Aerosil R972, and the mixture was kneaded using a three-roller mixer (EXAKT M-50; manufactured by EXAKT) to obtain 334.8 g of a photosensitive paste.

[0091] <Production of a substrate with a photosensitive layer> The photosensitive paste obtained by the above-described method was applied to a 50 μm-thick PET substrate by screen printing, and dried at a temperature of 55° C. for 15 minutes to form a 11 μm-thick photosensitive layer, thereby obtaining a substrate with a photosensitive layer. The content of the solvent (e) in the photosensitive layer was 1.0 mass %.

[0092] <Transfer Step> Next, the substrate with the ceramic green sheet and the obtained substrate with the photosensitive layer were placed opposite each other so that the photosensitive layer was in contact with the ceramic green sheet, and the photosensitive layer was transferred onto the ceramic green sheet using a press under the following transfer conditions: thermocompression temperature: 100°C, thermocompression time: 30 seconds, and thermocompression pressure: 0.3 MPa.

[0093] <Exposure Step A> An exposure mask is brought into contact with the exposed photosensitive layer, and an exposure device (PEM-6M; manufactured by Union Optical Co., Ltd.) is used to expose the layer to 300 mJ / cm2 at a wavelength of 365 nm. ２ Full line exposure was performed. The exposure mask used had thin lines with an opening width ranging from 5 to 40 μm and in 1 μm increments. Furthermore, as a sample for evaluating line width uniformity, an exposure mask was used in which a total of 25 blocks, five vertical and five horizontal, had thin lines with the above line widths. Furthermore, as a sample for evaluating the probability of disconnection, an exposure mask with an opening having a width (L) of 40 μm and a length of 4.0 cm and having the shape shown in FIG. 1 was used.

[0094] <Developing step> 0.2% by mass of Na ２ CO ３ The substrate having the exposed photosensitive layer was immersed in the solution, and then rinsed with ultrapure water to obtain a ceramic green sheet substrate having a conductive pattern.

[0095] The results of the evaluation by the above-mentioned method are shown in Table 1.

[0096] (Examples 2 to 3, Comparative Example 1) In <Production of substrate with photosensitive layer>, the same procedure as in Example 1 was carried out except that the drying conditions were changed as shown in Table 1, and the content of the solvent (e) in the photosensitive layer was as shown in Table 1. Using the obtained substrate with a photosensitive layer, a ceramic green sheet with a conductive pattern was obtained in the same manner as in Example 1. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0097] (Examples 4 to 6, Comparative Example 2) Ceramic green sheets with conductive patterns were obtained in the same manner as in Examples 1 to 3 and Comparative Example 1, except that the <transfer step> was replaced by a <lamination step> in which the base material of the substrate with a photosensitive layer was not peeled off, and the <exposure step A> was replaced by an <exposure step B> in which an exposure mask was brought into contact with the base material of the substrate with a photosensitive layer and the base material was peeled off after exposure. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0098] (Examples 7-8) <Preparation of Photosensitive Paste> 7.4 g of c-1, 7.4 g of c-2, 2.0 g of N-1919, 60.0 g of e-1, 7.5 g of UA-122P, 0.4 g of L-1980N, and 0.4 g of G-700 were placed in a 200 mL clean bottle and mixed using a planetary centrifugal vacuum mixer "Awatori Rentaro (registered trademark)" ARE-310 (Thinky Corporation) to obtain 85.1 g of resin solution. The obtained resin solution was mixed with 248.1 g of Ag particles and 1.6 g of Aerosil R972 and kneaded using a three-roller mixer (EXAKT M-50; EXAKT) to obtain 334.8 g of photosensitive paste.

[0099] In <Production of substrate with photosensitive layer>, the same procedures as in Example 1 were carried out except that the drying conditions were changed as shown in Table 1, and the content of the solvent (e) in the photosensitive layer was as shown in Table 1. Using the obtained substrate with photosensitive layer, a ceramic green sheet with a conductive pattern was obtained in the same manner as in Example 1. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0100] (Examples 9-10) <Preparation of Photosensitive Paste> 7.4 g of c-1, 7.4 g of c-3, 2.0 g of N-1919, 60.0 g of e-1, 7.5 g of UA-122P, 0.4 g of L-1980N, and 0.4 g of G-700 were placed in a 200 mL clean bottle and mixed using a planetary centrifugal vacuum mixer "Awatori Rentaro (registered trademark)" ARE-310 (Thinky Corporation) to obtain 85.1 g of resin solution. The obtained resin solution was mixed with 248.1 g of Ag particles and 1.6 g of Aerosil R972 and kneaded using a three-roller mixer (EXAKT M-50; EXAKT) to obtain 334.8 g of photosensitive paste.

[0101] In <Production of substrate with photosensitive layer>, the same procedures as in Example 1 were carried out except that the drying conditions were changed as shown in Table 1, and the content of the solvent (e) in the photosensitive layer was as shown in Table 1. Using the obtained substrate with photosensitive layer, a ceramic green sheet with a conductive pattern was obtained in the same manner as in Example 1. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0102] (Examples 11 and 12) The same procedures as in Example 1 were carried out except that in <Preparation of photosensitive paste>, solvent e-2 was used instead of solvent e-1, and in <Preparation of substrate with photosensitive layer>, the drying conditions were changed as shown in Table 1, and the solvent (e) content in the photosensitive layer was as shown in Table 1. Using the obtained substrate with photosensitive layer, a ceramic green sheet with a conductive pattern was obtained in the same manner as in Example 1. The results of evaluation by the above-mentioned method are shown in Table 1.

[0103] (Examples 13 and 14) Ceramic green sheets with conductive patterns were obtained in the same manner as in Examples 11 and 12, except that the <transfer step> was replaced by a <lamination step> in which the base material of the substrate with a photosensitive layer was not peeled off, and the <exposure step A> was replaced by an <exposure step B> in which an exposure mask was brought into contact with the base material of the substrate with a photosensitive layer and the base material was peeled off after exposure. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0104] (Examples 15 to 22) Base materials for substrates with photosensitive layers were obtained in the same manner as in Example 1, except that the thickness of the photosensitive layer and the drying conditions in <Production of substrate with photosensitive layer> were changed as shown in Table 1. Using the obtained base materials for substrates with photosensitive layers, ceramic green sheets with conductive patterns were obtained in the same manner as in Example 1, except that the exposure step was changed as shown in Table 1. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0105] (Comparative Example 3) Instead of the <transfer step>, a photosensitive paste was directly applied onto the ceramic green sheet of the ceramic green sheet-attached substrate, and dried at a temperature of 120°C for 4 minutes to form a photosensitive layer with a thickness of 11 µm. The content of the solvent (e) in the photosensitive layer was as shown in Table 1. Using the base material of the obtained substrate with a photosensitive layer, a ceramic green sheet with a conductive pattern was obtained in the same manner as in Example 1. The results of evaluation by the above-mentioned method are shown in Table 1.

[0106] Comparative Examples 4 and 5 Ceramic green sheets with conductive patterns were obtained in the same manner as in Examples 1 and 2, except that in the exposure step, exposure was performed without contact with an exposure mask. The results of evaluation by the above-mentioned methods are shown in Table 1.

[0107]

[0108] L opening width

Claims

1. A photosensitive layer is prepared on a substrate containing conductive particles (a), non-conductive particles (b), alkali-soluble resin (c), photosensitive agent (d), and solvent (e), wherein the alkali-soluble resin (c) has a glass transition temperature of 30°C to 70°C and contains a carboxyl group-containing resin that does not have an unsaturated double bond, and the solvent (e) has a content of 5.0% by mass or less. A step of transferring the photosensitive layer from the substrate onto a ceramic green sheet (transfer step) is performed. The process of exposing the photosensitive layer by bringing the exposure mask into contact with it (exposure process A), and, The process of developing the photosensitive layer after exposure to form a conductive pattern (development process). A method for manufacturing a ceramic green sheet with a conductive pattern, having the following elements in this order.

2. A photosensitive layer is prepared on a substrate containing conductive particles (a), non-conductive particles (b), alkali-soluble resin (c), photosensitive agent (d), and solvent (e), wherein the alkali-soluble resin (c) has a glass transition temperature of 30°C to 70°C and contains a carboxyl group-containing resin that does not have an unsaturated double bond, and the solvent (e) has a content of 5.0% by mass or less. The photosensitive layer is then laminated onto a ceramic green sheet (lamination step). The process involves bringing an exposure mask into contact with the substrate of a photosensitive layer and exposing it (exposure process B), and The process of developing the photosensitive layer after exposure to form a conductive pattern (development process). A method for manufacturing a ceramic green sheet with a conductive pattern, having the following elements in this order.

3. A method for producing a conductive patterned ceramic green sheet according to claim 1 or 2, wherein the solvent (e) content in the photosensitive layer is 0.1% by mass or more.

4. A method for producing a conductive patterned ceramic green sheet according to claim 1 or 2, wherein the photosensitive layer contains a polyether-modified polydimethylsiloxane.

5. A method for producing a conductive patterned ceramic green sheet according to claim 1 or 2, further comprising the step of applying a photosensitive paste containing conductive particles (a), non-conductive particles (b), alkali-soluble resin (c), photosensitive agent (d), and solvent (e) onto a substrate by screen printing, and drying to form a photosensitive layer, thereby obtaining a substrate with a photosensitive layer.

6. The method for producing a conductive patterned ceramic green sheet according to claim 1 or 2, wherein the solvent (e) includes a solvent having a boiling point of 150 to 300°C at atmospheric pressure.

7. A method for manufacturing a conductive patterned ceramic green sheet according to claim 1 or 2, wherein the thickness of the photosensitive layer is greater than 10 μm and less than or equal to 25 μm.

8. A method for producing a conductive patterned ceramic green sheet according to claim 1 or 2, wherein the ceramic green sheet contains a photosensitive organic component.

9. A method for manufacturing a laminate comprising multiple ceramic green sheets with conductive patterns stacked together, A step of forming a first conductive pattern and obtaining a conductive patterned ceramic green sheet by the method for manufacturing a conductive patterned ceramic green sheet according to claim 1 or 2, A step of forming a ceramic green sheet on the conductive pattern side of a first conductive patterned ceramic green sheet, and A step of forming a second conductive pattern on a ceramic green sheet having a first conductive pattern formed on it, using the method for manufacturing a ceramic green sheet with a conductive pattern according to claim 1 or 2. A method for manufacturing a laminate having the following characteristics.

10. A method for manufacturing a laminate comprising multiple ceramic green sheets with conductive patterns stacked together, A step of obtaining a plurality of conductive patterned ceramic green sheets by the method for manufacturing conductive patterned ceramic green sheets according to claim 1 or 2, and A process of laminating and heat-pressing multiple ceramic green sheets with conductive patterns. A method for manufacturing a laminate having the following characteristics.

11. A method for manufacturing a fired body, comprising the steps of obtaining a ceramic green sheet with a conductive pattern by the manufacturing method described in claim 1 or 2, and firing the obtained ceramic green sheet with a conductive pattern.