Electronic component manufacturing kits and their uses

Abstract

To provide a technique capable of stably producing an electronic part having a precise conductive layer.SOLUTION: The production kit comprises a paste for substrate formation and a photosensitive conductive paste. In the electronic part production kit, an HSP distance between a binder resin of the paste for substrate formation, and an organic solvent of the photosensitive conductive paste, is 1.0 or greater and 2.5 or smaller. In addition, an HSP distance between the binder resin of the paste for substrate formation and a surface treatment agent of conductive inorganic powder of the photosensitive conductive paste is 1.0 or greater. Therefore, sheet attack of the photosensitive conductive paste to a green sheet can be properly controlled, and adhesion of the conductive inorganic powder to the green sheet surface via the surface treatment agent, can be suppressed. As the result, generation of a residue can be preferably suppressed while securing a long development margin. Therefore, an electronic part having a precise conductive layer can be stably produced.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a kit for manufacturing electronic components. Specifically, the present invention relates to a kit for manufacturing electronic components comprising a substrate forming paste for forming an inorganic substrate for electronic components, and a photosensitive conductive paste for forming a conductive layer on the surface of the inorganic substrate. [Background technology]

[0002] Electronic components such as high-frequency inductors typically consist of an insulating inorganic substrate and a linear conductive layer formed on the surface of the inorganic substrate in a predetermined pattern. Photolithography has been proposed as one method for manufacturing these electronic components. In such a photolithography method, for example, an electronic component manufacturing kit (hereinafter also simply referred to as a "manufacturing kit") is used, which includes a substrate-forming paste containing insulating inorganic powder and a binder resin, and a photosensitive conductive paste containing conductive inorganic powder, a photocurable resin, and an organic solvent.

[0003] In the manufacturing of electronic components using the above manufacturing kit, first, a green sheet, which is a precursor material for an inorganic substrate, is formed using a substrate forming paste. Then, a photosensitive conductive paste is applied in layers to the surface of the green sheet and dried to form a film. Next, a photomask having slits (openings) in a predetermined pattern is placed over the film, and light is irradiated onto a portion of the film exposed through the slits to form a photocured film. Next, a developing process is performed to remove the unexposed parts (uncured film) that were shielded from light by the photomask using a developing solution. As a result, a photocured film with a predetermined pattern remains on the surface of the green sheet. Finally, by firing this photocured film and the green sheet, an electronic component having a conductive layer with a predetermined pattern is manufactured.

[0004] Patent Document 1 discloses an example of a technique for manufacturing electronic components using photolithography. The technique described in Patent Document 1 uses a conductive paste in which the viscosity of the reactive compound (photocurable resin) at 60°C is adjusted to within the range of 5.0 Pa·s to 100.0 Pa·s. This suppresses the absorption of the reactive compound in the photosensitive conductive paste into the green sheet, enabling the formation of a high-resolution pattern. Furthermore, in the technique described in Patent Document 1, the solubility parameter (SP value) of the solvent (organic solvent) of the photosensitive conductive paste is 19.5 to 21.3 (J / cm²). 3 ) 1 / 2 It is adjusted within a certain range. This suppresses the residue of unexposed areas after development (generation of residue), and also facilitates the formation of a highly detailed conductive layer (development of the photocured film). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Patent No. 6662491 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, there was still room for improvement in the manufacturing of electronic components using photolithography. Specifically, even when the solubility of the organic solvent was adjusted as described in Patent Document 1 above, problems such as the generation of residue after development and a decrease in ease of development due to a shortened development margin sometimes occurred. The "development margin" refers to the time from the point in development when the unexposed portion is completely removed (breakpoint (BP)) until the point in time when peeling or disconnection occurs in the exposed portion (photocured film). In other words, when the development margin is shortened, peeling of the photocured film occurs immediately after the unexposed portion is removed, making it difficult to develop a precise photocured film (conductive layer).

[0007] The present invention was made to solve the above-mentioned problems, and its objective is to provide a technology that suppresses the generation of residue after development processing, ensures a sufficiently long development margin, and enables the stable manufacture of electronic components having a precise conductive layer. [Means for solving the problem]

[0008] As described above, even when the solubility of the organic solvent in the photosensitive conductive paste was adjusted according to the technology described in Patent Document 1, residue generation and shortening of the development margin sometimes occurred. The inventors investigated the causes of these problems and obtained the following findings.

[0009] First, in the manufacturing of electronic components, a green sheet is formed using a substrate-forming paste, and a photosensitive conductive paste is applied to the surface of the green sheet. At this time, some of the organic solvent in the photosensitive conductive paste may dissolve into the green sheet, causing a sheet attack that dissolves the binder resin of the green sheet. When this sheet attack occurs appropriately, the adhesion of the photocured film to the surface of the green sheet is improved, and peeling of the photocured film during the development process is suppressed, thus lengthening the development margin. On the other hand, if the sheet attack is excessive, the adhesion of not only the photocured film but also the unexposed areas increases, promoting the retention of unexposed areas (generation of residue) after the development process. The inventors speculated that the change in the frequency of residue generation and the length of the development margin when adjusting the solubility of the organic solvent in the photosensitive conductive paste is due to fluctuations in the degree of the sheet attack described above. However, the sheet attack is due to the interaction between the organic solvent in the photosensitive conductive paste and the binder resin of the substrate-forming paste (green sheet). Therefore, as described in Patent Document 1, it is difficult to accurately control the degree of sheet attack by adjusting only the solubility of the organic solvent in the photosensitive conductive paste. Based on this finding, the inventors conceived of adjusting both the solubility of the organic solvent in the photosensitive conductive paste and the solubility of the binder resin in the substrate forming paste to accurately control the degree of sheet attack.

[0010] Next, the inventors, after further investigation, found that residue after development can be generated by factors other than sheet attack. Specifically, the particle surface of general conductive inorganic powders is treated with a surface treatment agent to suppress aggregation of particles. Depending on the combination of the surface treatment agent of such conductive inorganic powder and the binder resin of the green sheet, the conductive inorganic powder may adhere to the green sheet surface via the surface treatment agent. In this case, even if excessive sheet attack is prevented and organic components in the unexposed areas are appropriately removed during the development process, conductive inorganic powder directly adhering to the green sheet surface may become residue. Based on this finding, the inventors considered that if the degree of sheet attack could be appropriately controlled and adhesion between the green sheet and the conductive inorganic powder via the surface treatment agent could be suppressed, the generation of residue could be appropriately suppressed.

[0011] The electronic component manufacturing kit disclosed herein is based on the above-described findings. The manufacturing kit comprises a substrate forming paste (A) for forming an insulating inorganic substrate and a photosensitive conductive paste (B) for forming a conductive layer on the surface of the inorganic substrate. The substrate forming paste (A) contains insulating inorganic powder (A1) and a binder resin (A2). The photosensitive conductive paste (B) contains conductive inorganic powder (B1) with a surface treatment agent attached to the particle surface, a photocurable resin (B2), a photopolymerization initiator (B3), and an organic solvent (B4). In the electronic component manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is 1.0 or more and 2.5 or less. Furthermore, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is 1.0 or greater.

[0012] Here, "HSP distance" as used herein is the absolute value of the difference between the Hansen solubility parameters (HSP values) of two components. Specifically, the HSP value is a parameter that defines solubility using three elements: the energy due to intermolecular dispersion forces (dispersion term dD), the energy due to intermolecular dipole interactions (polarity term dP), and the energy due to intermolecular hydrogen bonding (hydrogen bonding term dH). These three elements can each be plotted in three-dimensional space (Hansen space). The distance between the coordinates (dD,dP,dH) plotted in the Hansen space, with the starting point being (0,0,0) and the ending point being the "HSP value." The "HSP distance" is the distance between the coordinates of the two components in the Hansen space and can be calculated based on the following formula. In the following formula, "dD1" is the dispersion term of one substance (substance 1), "dP1" is the polarity term of substance 1, and "dH1" is the hydrogen bonding term of substance 1. "dD2" is the dispersion term of the other substance (substance 2), "dP2" is the polarity term of substance 2, and "dH2" is the hydrogen bonding term of substance 2. Note that the HSP value and HSP distance in this specification are both values ​​at 25°C, and their unit is (J / cm²). 3 ) 1 / 2 That is the case. HSP distance=[4×(dD1-dD2) 2 +(dP1-dP2) 2 +(dH1-dH2) 2 ] 1 / 2

[0013] Furthermore, when the HSP distance between two components is small, it can be said that the two components are easily soluble with each other. In the above-described manufacturing kit, the upper limit of the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is adjusted to 2.5 or less. As a result, a proper sheet attack occurs in which the binder resin (A2) dissolves in the organic solvent (B4), ensuring a sufficiently long development margin. On the other hand, two components with a large HSP distance are not easily soluble with each other. In the above-described manufacturing kit, the lower limit of the HSP distance between the binder resin (A2) and the organic solvent (B4) is adjusted to 1.0 or more. As a result, excessive sheet attack can be prevented, thus suppressing the generation of residue due to increased adhesion of unexposed areas to the green sheet surface. Furthermore, since the HSP distance is calculated based on the dispersion term dD, the polarity term dP, and the hydrogen bonding term dH, it is possible to evaluate not only the solubility between the two components but also their adhesion. In the manufacturing kit with the above configuration, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is adjusted to 1.0 or more. As a result, adhesion between the green sheet and the conductive inorganic powder (B1) via the surface treatment agent is less likely to occur, thus more effectively suppressing the generation of residue. As described above, the electronic component manufacturing kit disclosed herein allows for the effective suppression of residue generation while ensuring a sufficiently long development margin, thereby enabling the stable manufacturing of electronic components with precise conductive layers.

[0014] In one preferred embodiment of the electronic component manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is 3.5 or less. This makes it easy to secure a longer development margin.

[0015] In the electronic component manufacturing kit disclosed herein, it is sufficient that the HSP distance between each component satisfies the above-mentioned range, and the HSP values ​​of each component themselves are not particularly limited. For example, the HSP value of the binder resin (A2) may be 17.0 to 22.0. The HSP value of the organic solvent (B4) may be 17.0 to 21.0. The HSP value of the surface treatment agent for the conductive inorganic powder (B1) may be 17.5 to 21.0.

[0016] In one preferred embodiment of the electronic component manufacturing kit disclosed herein, the conductive inorganic powder (B1) contains silver-based particles. This enables the manufacture of electronic components that offer an excellent balance between cost and electrical resistance.

[0017] Furthermore, as another aspect of the technology disclosed herein, a photosensitive conductive paste used in a manufacturing kit for the above configuration is provided. Such a photosensitive conductive paste (B) comprises a conductive inorganic powder (B1) with a surface treatment agent attached to its surface, a photocurable resin (B2), a photopolymerization initiator (B3), and an organic solvent (B4). The HSP distance between the binder resin (A2) of the substrate forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is 1.0 or more and 2.5 or less, and the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is 1.0 or more.

[0018] As another aspect of the technology disclosed herein, a method for manufacturing an electronic component is provided. The method for manufacturing such an electronic component is a method for manufacturing an electronic component using the manufacturing kit having the above-described configuration. The method for manufacturing such an electronic component includes a green sheet preparation step of preparing a green sheet obtained by shaping a base material forming paste (A) into a sheet form, a film-like body forming step of applying a photosensitive conductive paste (B) to the surface of the green sheet and drying the photosensitive conductive paste (B) to form a film-like body, an exposure step of covering the film-like body with a photomask having slits of a predetermined pattern and irradiating light to a part of the film-like body exposed from the slits to form a photocured film, a development step of removing an uncured film-like body shielded by the photomask with a developer, and a firing step of firing the green sheet and the photocured film remaining on the surface of the green sheet.

Brief Description of Drawings

[0019] [Figure 1] It is a cross-sectional view for explaining a film-like body forming step in a method for manufacturing an electronic component according to an embodiment. [Figure 2] It is a cross-sectional view for explaining an exposure step in a method for manufacturing an electronic component according to an embodiment. [Figure 3] It is a cross-sectional view for explaining a development step in a method for manufacturing an electronic component according to an embodiment.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, preferred embodiments of the technology disclosed herein will be described. Matters other than those specifically mentioned in this specification and necessary for implementing the technology disclosed herein can be understood based on the technical content taught in this specification and the general technical common sense of those skilled in the art in this field. The technology disclosed herein can be implemented based on the content disclosed in this specification and the technical common sense in this field. Also, the notation "A to B" (A and B are arbitrary numbers) indicating a range in this specification includes the meaning of "not less than A and not more than B", as well as the meaning of "preferably greater than A" and "preferably less than B".

[0021] 1. Kit for manufacturing electronic components First, the electronic component manufacturing kit disclosed herein will be described. In this specification, "electronic component manufacturing kit" refers to a combination of several types of paste compositions used in the manufacture of electronic components. Here, "paste" is a term that includes inks and slurries. The manufacturing kit disclosed herein comprises at least a substrate forming paste (A) and a photosensitive conductive paste (B). The components of each paste will be described in detail below.

[0022] (1) Paste for forming the base material (A) The substrate-forming paste (A) is a paste for forming an insulating inorganic substrate. This substrate-forming paste (A) contains at least insulating inorganic powder (A1) and a binder resin (A2). By molding this substrate-forming paste (A) into a sheet, a green sheet, which is a precursor of the inorganic substrate, can be produced. When this green sheet is fired, the binder resin (A2) burns away and the insulating inorganic powder (A1) sintersects to form the inorganic substrate. The components of the substrate-forming paste (A) are described below.

[0023] (1-1) Insulating inorganic powder (A1) The insulating inorganic powder (A1) is an inorganic material that becomes the main component of the inorganic substrate after firing. The insulating inorganic powder (A1) has a predetermined insulation property and can be used without particular limitation as long as it remains without burning out during the firing process. As an example of such an insulating inorganic powder (A1), oxide-based ceramics such as alumina (Al2O3), silica (SiO2), zirconia (ZrO2), titania (TiO2), etc. can be mentioned. Also, as other examples of the insulating inorganic powder (A1), nitride-based ceramics such as aluminum nitride (AlN), silicon nitride (Si3N4), etc. can be mentioned. Further, when forming a transparent substrate as the inorganic substrate, glass powder can also be used as the insulating inorganic powder (A1). As a preferred example of such glass powder, SiO2-based glass containing a silicon component (SiO2) as the main component can be mentioned. Specific examples of such SiO2-based glass include B2O3-SiO2-based glass, SiO2-RO-based glass (R is a group 2 element (Mg, Ca, Sr, Ba, Ra, etc.)), SiO2-RO-Al2O3-based glass, SiO2-RO-Y2O3-based glass, SiO2-RO-B2O3-based glass, SiO2-Al2O3-based glass, SiO2-ZnO-based glass, SiO2-ZrO2-based glass, etc. Also, as other examples of glass powder, RO-based glass, lead-based glass, lead-lithium-based glass, etc. can be mentioned.

[0024] The particle size of the insulating inorganic powder (A1) in the paste (A) for forming the substrate is not particularly limited, but a micron size is preferable. For example, from the viewpoint of ease of sheet forming and sintering, the D 50 lower limit of the particle size of the insulating inorganic powder (A1) is preferably 1 μm or more, more preferably 2 μm or more, and particularly preferably 3 μm or more. On the other hand, from the viewpoint of reducing the surface roughness of the substrate after firing, the D 50 upper limit of the particle size of the insulating inorganic powder (A1) is preferably 10 μm or less, more preferably 8 μm or less, and particularly preferably 5 μm or less. Note that the "D 50 particle size" in this specification is the particle size corresponding to 50% of the integrated value from the smaller side in the volume-based particle size distribution based on the laser diffraction / scattering method.

[0025] Furthermore, the content of insulating inorganic powder (A1) in the substrate-forming paste (A) is preferably 15% by mass or more, more preferably 20% by mass or more, even more preferably 25% by mass or more, and particularly preferably 30% by mass or more. This reduces the resin component on the substrate surface and suppresses excessive sheet attack. On the other hand, the upper limit of the content of insulating inorganic powder (A1) is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, and particularly preferably 35% by mass or less. This ensures that a resin component that can easily form electrodes is secured. In this specification, "content" refers to the mass ratio (mass%) when the total weight of the paste is 100% by mass, unless otherwise specified.

[0026] (1-2) Binder resin (A2) A binder resin (A2) is added to maintain the shape of the green sheet before firing. This binder resin (A2) is made of a resin material that has a predetermined viscosity and burns off during the firing process. Examples of such resin materials include butyral resin, vinyl resin, cellulose resin, alkyd resin, acrylic resin, epoxy resin, fluororesin, silicone resin, polyester resin, ketone resin, polyamide resin, coumarone resin, and polyimide resin. The binder resin (A2) may also be a mixture of two or more of these resin materials. Among the above-mentioned resin materials, butyral resin is preferred. Butyral resin is a polymer that contains butyral groups, hydroxyl groups, and acetate groups as monomer unit structures. An example of such a butyral resin is polyvinyl butyral resin (PVB), which is obtained by reacting polyvinyl alcohol and butyraldehyde. However, the specific components of the binder resin (A2) are not particularly limited as long as they satisfy the conditions regarding the HSP distance described later, and conventionally known resin materials that can function as a binder can be used without any particular restrictions. For example, commercially available binder resins sold by companies such as Shin-Nakamura Chemical Industry Co., Ltd., Mitsubishi Chemical Corporation, and Shin-Etsu Chemical Co., Ltd. can be used.

[0027] Furthermore, the lower limit of the binder resin (A2) content in the substrate forming paste (A) is preferably 5% by mass or more. This allows for appropriate sheet attack, where the organic solvent (B4) of the photosensitive conductive paste (B), described later, dissolves the binder resin (A2) of the green sheet. Also, considering the shape stability of the green sheet, the lower limit of the binder resin (A2) content is preferably 6% by mass or more, more preferably 8% by mass or more, and even more preferably 10% by mass or more. On the other hand, considering the density of the inorganic substrate after firing, the upper limit of the insulating inorganic powder (A1) content is preferably 20% by mass or less, more preferably 17% by mass or less, and even more preferably 15% by mass or less.

[0028] (1-3) Dispersion medium (A3) Furthermore, the substrate-forming paste (A) may contain a dispersion medium (A3) that disperses the above-mentioned components. The dispersion medium (A3) is a liquid component that imparts appropriate viscosity and fluidity to the paste, improving its handling and moldability. However, in the substrate-forming paste (A) disclosed herein, the dispersion medium (A3) is not an essential component. That is, if sufficient viscosity and fluidity to form a green sheet can be obtained when mixing the components other than the dispersion medium (A3) (for example, insulating inorganic powder (A1) and binder resin (A2)), then it is not necessary to add the dispersion medium (A3). Therefore, the content of the dispersion medium (A3) in the substrate-forming paste (A) can be adjusted considering the moldability of the green sheet. For example, the content of the dispersion medium (A3) in the substrate-forming paste (A) can be approximately 0% to 70% by mass, typically 15% to 65% by mass, for example, 30% to 60% by mass.

[0029] Furthermore, the type of dispersion medium (A3) is not particularly limited, and conventionally known organic dispersion mediums can be used alone or in combination of two or more. Examples of such organic dispersion mediums include alcohol-based solvents such as terpineol; glycol-based solvents such as ethylene glycol, propylene glycol, and diethylene glycol; ether-based solvents such as dipropylene glycol methyl ether and methyl cellosolve (ethylene glycol monomethyl ether); ester-based solvents such as diethylene glycol monobutyl ether acetate, butyl carbitol acetate (diethylene glycol monobutyl ether acetate), and isobornyl acetate; hydrocarbon-based solvents such as toluene, xylene, naphtha, and petroleum hydrocarbons; mineral spirits; and the like. The dispersion medium (A3) may also be selected considering its boiling point. For example, by using a dispersion medium (A3) with a boiling point of 150°C or higher, the natural evaporation of the dispersion medium (A3) can be prevented, improving the shelf life of the paste. On the other hand, if a dispersion medium (A3) with a boiling point of 250°C or lower is used, the dispersion medium (A3) can be easily removed during the drying process after green sheet formation.

[0030] (1-4) Other ingredients Furthermore, the substrate-forming paste (A) may contain components other than those described above, as long as they do not significantly impair the effects of the technology disclosed herein. These other components are not particularly limited, and conventionally known additives can be used alone or in combination of two or more. Examples of such other additives include antioxidants, plasticizers, surfactants, leveling agents, thickeners, dispersants, defoaming agents, gelling inhibitors, stabilizers, and preservatives.

[0031] (2) Photosensitive conductive paste (B) Next, a photosensitive conductive paste (B) will be described. The photosensitive conductive paste (B) disclosed herein is a paste for forming a conductive layer on the surface of an inorganic substrate. This photosensitive conductive paste (B) contains at least a conductive inorganic powder (B1), a photocurable resin (B2), a photopolymerization initiator (B3), and an organic solvent (B4).

[0032] (2-1) Conductive inorganic powder (B1) The conductive inorganic powder (B1) is an inorganic powder that forms the main component of the conductive layer after firing. The conductive inorganic powder (B1) can be used without particular limitations as long as it has a predetermined electrical conductivity and remains intact without burning during the firing process. Examples of such conductive inorganic powder (B1) include elemental metals such as gold (Au), silver (Ag), copper (Cu), platinum (Pt), palladium (Pd), aluminum (Al), nickel (Ni), ruthenium (Ru), rhodium (Rh), tungsten (W), iridium (Ir), and osmium (Os), as well as compounds and alloys containing these. A preferred example of conductive inorganic powder (B1) is silver-based particles. These "silver-based particles" encompass all particulate materials containing the element silver (Ag). Examples of such silver-based particles include particles made of elemental silver, particles made of silver alloys, and core-shell particles containing silver components. Examples of silver alloys include silver-palladium (Ag-Pd) alloys, silver-platinum (Ag-Pt) alloys, and silver-copper (Ag-Cu) alloys. Examples of core-shell particles include silver-ceramic core-shell particles, which consist of a core particle containing silver and a ceramic shell covering the core particle. These silver-based particles are relatively inexpensive and have high electrical conductivity, thus contributing to the manufacture of electronic components with an excellent balance between conductivity and cost.

[0033] Furthermore, the photosensitive conductive paste (B) disclosed herein uses conductive inorganic powder (B1) on which a surface treatment agent is attached to the particle surface. This suppresses aggregation between particles and improves the dispersibility of particles in the paste, thereby contributing to the uniformity of the density of the conductive layer after firing. Examples of surface treatment agents include organic acids, surfactants, organometallic compounds, chelating agents, and polymer dispersants. Examples of the above organic acids include fatty acids such as propionic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, acrylic acid, oleic acid, linoleic acid, arachidonic acid, and ricinoleic acid. Salts of these organic acids (organic acid salts) can also be used as surface treatment agents. Examples of chelating agents include azoles such as benzotriazole or their salts, as well as succinic acid, malonic acid, glutaric acid, and adipic acid. However, the specific components of the surface treatment agent are not particularly limited as long as they satisfy the conditions regarding the HSP distance described later, and conventionally known organic components that can function as a surface treatment agent for conductive inorganic powder (B1) can be used without any particular restrictions.

[0034] Furthermore, although not particularly limited, D of conductive inorganic powder (B1) 50 The upper limit of the particle size is preferably 5 μm or less, more preferably 4.5 μm or less, and particularly preferably 4 μm or less. As the particle size of the conductive inorganic powder (B1) decreases, the density of the conductive layer after firing tends to improve. On the other hand, if the particle size of the conductive inorganic powder (B1) becomes too small, coarse particles due to aggregation are more likely to occur, which may reduce the surface smoothness of the conductive layer. From this viewpoint, the D of the conductive inorganic powder (B1) 50 The particle size is preferably 0.1 μm or larger, more preferably 0.5 μm or larger, and particularly preferably 1 μm or larger.

[0035] Furthermore, the content of conductive inorganic powder (B1) in the photosensitive conductive paste (B) is preferably 74% by mass or more, more preferably 78% by mass or more, more preferably 79% by mass or more, even more preferably 80% by mass or more, and particularly preferably 81% by mass or more. This makes it possible to form a dense and thick conductive layer, enabling the manufacture of low-resistance electronic components. However, if the concentration of conductive inorganic powder (B1) is increased too much, the fluidity of the paste will decrease significantly, which may make it difficult to uniformly apply the photosensitive conductive paste (B) to the surface of the green sheet. For this reason, the content of conductive inorganic powder (B1) is preferably 90% by mass or less, and more preferably 85% by mass or less. Note that pastes containing a high concentration of conductive inorganic powder (B1) tend to have difficulty transmitting light into the interior of the film during the exposure process, which reduces the adhesion of the photocured film to the green sheet and shortens the development margin (making peeling of the photocured film more likely). However, according to the technology disclosed herein, sheet attack can be appropriately generated to improve the adhesion of the photocured film to the green sheet, thereby ensuring a sufficiently long development margin even when a high concentration of conductive inorganic powder (B1) is included.

[0036] (2-2) Photocurable resin (B2) The photocurable resin (B2) is an organic compound that hardens when irradiated with light (ultraviolet light) through polymerization reactions, crosslinking reactions, etc. The photosensitive conductive paste (B) disclosed herein can use any conventionally known photocurable resin that can be used in photosensitive pastes without particular limitation. For example, the photocurable resin (B2) may be a relatively high molecular weight (e.g., a weight-average molecular weight of 6000 or more) photocurable polymer, or a relatively low molecular weight (e.g., a weight-average molecular weight of less than 6000) photocurable oligomer. When a photocurable polymer is used as the photocurable resin (B2), the adhesion of the film-like material to the green sheet before photocuring can be improved. Considering such adhesion to the green sheet, the weight-average molecular weight Mw of the photocurable resin (B2) is preferably 500 or more, more preferably 750 or more, even more preferably 1000 or more, and particularly preferably 1500 or more. On the other hand, the upper limit of the weight-average molecular weight Mw of the photocurable resin (B2) is preferably 60,000 or less, more preferably 50,000 or less, even more preferably 40,000 or less, and particularly preferably 30,000 or less.

[0037] A suitable example of a photocurable resin (B2) is a (meth)acrylic resin. Because (meth)acrylic resins have excellent flexibility and durability after photocuring, peeling and damage of the photocured film before firing can be suppressed. A "(meth)acrylic resin" is a photocurable resin having a (meth)acryloyl group. Here, "(meth)acryloyl group" is a term that includes both "methacryloyl group (-C(=O)-C(CH3)=CH2)" and "acryloyl group (-C(=O)-CH=CH2)". Suitable examples of the (meth)acrylic resin include alkyl (meth)acrylate homopolymers and copolymers in which alkyl (meth)acrylate is the main monomer and a copolymer containing a co-monomer that is copolymerizable with the main monomer. Specific examples of the above homopolymers include, for example, polymethyl (meth)acrylate, polyethyl (meth)acrylate, and polybutyl (meth)acrylate. Specific examples of copolymers include, for example, block copolymers containing polymers of methacrylate esters and polymer blocks of acrylic acid esters as repeating structural units. Specific examples of methacrylate esters include methyl methacrylate, propyl methacrylate, n-butyl methacrylate, and t-butyl methacrylate. Specific examples of acrylic acid esters include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, t-butyl acrylate, and n-hexyl acrylate. The term "(meth)acrylate" above encompasses both "methacrylate" and "acrylate." Furthermore, from the viewpoint of improving photocurability, it is preferable that the (meth)acrylic resin has a (meth)acryloyl group (preferably an acryloyl group) in its side chain. Commercially available (meth)acrylic resins can be used without particular limitation as described above. Examples of such commercially available (meth)acrylic resins include those from Nippon Kayaku Co., Ltd., Kyoeisha Chemical Co., Ltd., Shin Nakamura Chemical Industry Co., Ltd., and Toagosei Co., Ltd.

[0038] Furthermore, the content of the photocurable resin (B2) in the photosensitive conductive paste (B) is preferably 2% by mass or more, more preferably 4% by mass or more, and particularly preferably 6% by mass or more. This allows for the formation of a photocured film that adheres properly to the surface of the green sheet with a short exposure time. On the other hand, the upper limit of the content of the photocurable resin (B2) is preferably 30% by mass or less, more preferably 20% by mass or less, and particularly preferably 15% by mass or less. This prevents photocuring in areas that are shielded from light during the exposure process and improves the precision of the photocured film after development.

[0039] (2-3) Photopolymerization initiator (B3) The photopolymerization initiator (B3) is a component that decomposes upon irradiation with light (e.g., ultraviolet light), generating active species such as radicals and cations, thereby promoting the polymerization reaction of the photocurable resin (B2). The photocurable resin (B2) can be selected from conventionally known types, and one type can be used alone or two or more types can be used in appropriate combinations depending on the type of photocurable resin (B2). A suitable example of the photopolymerization initiator (B2) is 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4-diethylthioxanthone, benzophenone, etc.

[0040] Furthermore, from the viewpoint of preventing photocuring of the portion shielded by the photomask during the exposure process, the content of the photopolymerization initiator (B3) in the photosensitive conductive paste (B) is preferably 5% by mass or less, more preferably 4% by mass or less, even more preferably 3% by mass or less, and particularly preferably 2% by mass or less. On the other hand, from the viewpoint of more favorably shortening the exposure time, the content of the photopolymerization initiator (B3) is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more, and particularly preferably 1% by mass or more.

[0041] (2-4) Organic solvents (B4) The organic solvent (B4) can be the same type as the dispersion medium (A3) of the paste (A) for forming the substrate. Specifically, the organic solvent (B4) for the photosensitive conductive paste (B) can be an alcohol-based solvent such as terpineol; a glycol-based solvent such as ethylene glycol, propylene glycol, or diethylene glycol; an ether-based solvent such as dipropylene glycol methyl ether, methyl cellosolve (ethylene glycol monomethyl ether), diethylene glycol dibutyl ether, or propylene glycol monophenyl ether; an ester-based solvent such as glycol ether acetate, 2,2,4-trimethyl-1,3-pentanediol 1-monoisobutyrate, butyl carbitol acetate (diethylene glycol monobutyl ether acetate), or isobornyl acetate; a hydrocarbon-based solvent such as toluene, xylene, naphtha, or petroleum hydrocarbons; or a mineral spirit. Furthermore, similar to the binder resin (A2) and surface treatment agent mentioned above, the specific components of the organic solvent (B4) are not particularly limited as long as they satisfy the conditions regarding the HSP distance described later, and conventionally known organic components that can function as an organic solvent for the photosensitive conductive paste (B) can be used without any particular restrictions. For example, commercially available organic solvents sold by companies such as Toho Chemical Industry Co., Ltd., Nippon Koryo Yakuhin Co., Ltd., Musashino Chemical Research Institute Co., Ltd., Dow Chemical Japan Ltd., and Nippon Terpene Co., Ltd. can be used.

[0042] Furthermore, the content of the organic solvent (B4) in the photosensitive conductive paste (B) is preferably 10% by mass or more. This allows for appropriate sheet attack on the green sheet. Also, considering the ease of handling of the photosensitive conductive paste (B), the content of the organic solvent (B4) is preferably 11% by mass or more, and more preferably 12% by mass or more. On the other hand, considering the density of the conductive layer after firing, the upper limit of the content of the organic solvent (B4) is preferably 20% by mass or less, more preferably 18% by mass or less, and even more preferably 15% by mass or less.

[0043] (2-5) Other additives Furthermore, the photosensitive conductive paste (B) may contain components other than the above-mentioned components (B1) to (B4), as long as they do not significantly impair the effects of the technology disclosed herein. These other additive components are not particularly limited, and conventionally known additive components can be used individually or in appropriate combinations of two or more. Examples of such other additive components include binder resins, ultraviolet absorbers, polymerization inhibitors, radical scavengers, antioxidants, plasticizers, surfactants, leveling agents, dispersants, defoamers, gelation inhibitors, stabilizers, and preservatives. For example, the photosensitive conductive paste (B) may contain the same type of binder resin as the binder resin (A2) of the substrate forming paste (A). For example, the binder resin content in the photosensitive conductive paste (B) is preferably 8.5% by mass or less, more preferably 8.0% by mass or less, even more preferably 7.5% by mass or less, and particularly preferably 7.0% by mass or less. This ensures sufficient density of the conductive layer after firing. On the other hand, the lower limit of the content of the organic binder (B5) may be 0% by mass (no binder resin), 2.0% by mass or more, 3.0% by mass or more, or 5.0% by mass or more. This allows for a more appropriate improvement in the adhesion of the photosensitive conductive paste (B) to the green sheet.

[0044] (3) HSP distance of each component The components of each paste have been described above. In the manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B), and the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B), are each adjusted to a predetermined range. This ensures a sufficiently long development margin while effectively suppressing the generation of residue, thereby enabling the stable manufacture of electronic components with precise conductive layers. A detailed explanation follows below.

[0045] First, in the manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) and the organic solvent (B4) is adjusted to 2.5 or less. This allows sufficient sheet attack to occur in the organic solvent (B4) of the photosensitive conductive paste (B), causing the binder resin (A2) of the green sheet (substrate forming paste (A)) to dissolve. As a result, the adhesion of the photocured film to the surface of the green sheet is improved, and a sufficiently long development margin can be secured. Note that if the HSP distance between the binder resin (A2) and the organic solvent (B4) is made smaller, the development margin tends to become even longer. From this viewpoint, the HSP distance between the binder resin (A2) and the organic solvent (B4) is preferably 2.3 or less, more preferably 2.2 or less, even more preferably 2.1 or less, and particularly preferably 2.0 or less.

[0046] On the other hand, if the HSP distance between the binder resin (A2) and the organic solvent (B4) is made too small, excessive sheet attack may occur, which may increase the fixation of unexposed areas (uncured film-like material) and accelerate the generation of residue after development. For this reason, in the manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) and the organic solvent (B4) is adjusted to 1.0 or higher. Furthermore, from the viewpoint of further appropriately suppressing the generation of residue, the HSP distance between the binder resin (A2) and the organic solvent (B4) is preferably 1.2 or higher, more preferably 1.3 or higher, even more preferably 1.4 or higher, and particularly preferably 1.5 or higher.

[0047] Next, in the manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent for the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is adjusted to 1.0 or higher. This prevents the conductive inorganic powder (B1) from adhering to the green sheet surface via the surface treatment agent, and more effectively suppresses the generation of residue. Furthermore, increasing the HSP distance between the binder resin (A2) and the surface treatment agent for the conductive inorganic powder (B1) further can more effectively suppress the generation of residue. From this viewpoint, the HSP distance between the binder resin (A2) and the surface treatment agent is preferably 1.2 or higher, more preferably 1.3 or higher, even more preferably 1.4 or higher, and particularly preferably 1.5 or higher.

[0048] As described above, in the manufacturing kit disclosed herein, the HSP distance between the binder resin (A2) and the organic solvent (B4) is adjusted so that a sheet attack occurs that achieves a high level of both residue suppression and development margin. Furthermore, in this manufacturing kit, the HSP distance between the binder resin (A2) and the surface treatment agent of the conductive inorganic powder (B1) is adjusted so as to prevent adhesion between the conductive inorganic powder (B1) and the green sheet via the surface treatment agent. This makes it possible to more effectively prevent the generation of residue after development. As a result, the manufacturing kit disclosed herein enables the stable manufacture of electronic components having a precise conductive layer.

[0049] Although not limited to the technologies disclosed herein, the upper limit of the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is preferably 3.5 or less, more preferably 3.0 or less, even more preferably 2.7 or less, and particularly preferably 2.5 or less. Experiments have confirmed that by reducing the HSP distance between the binder resin (A2) and the surface treatment agent in this way, an even longer development margin can be secured.

[0050] Furthermore, the technology disclosed herein only requires that the HSP distance satisfies the above-mentioned conditions, and the specific HSP values ​​of each component are not particularly limited. For example, the lower limit of the HSP value of the binder resin (A2) of the substrate forming paste (A) may be 15 or higher, 16 or higher, or 17 or higher. On the other hand, the upper limit of the HSP value of the binder resin (A2) may be 25 or lower, 24 or lower, 23 or lower, or 22 or lower. Similarly, the lower limit of the HSP value of the organic solvent (B4) of the photosensitive conductive paste (B) may be 15 or higher, 16 or higher, or 17 or higher. On the other hand, the upper limit of the HSP value of the organic solvent (B4) may be 25 or lower, 24 or lower, 23 or lower, or 21 or lower. And the lower limit of the HSP value of the surface treatment agent for the conductive inorganic powder (B1) may be 15 or higher, 16 or higher, or 17 or higher. On the other hand, the upper limit of the HSP value of the surface treatment agent for conductive inorganic powder (B1) may be 25 or less, 24 or less, 23 or less, or 21 or less.

[0051] In this specification, the "HSP value of binder resin (A2)" is a value calculated based on turbidity titration, where binder resin (A2) is dropped into a solvent with a high HSP value and a solvent with a low HSP value, and the HSP value is calculated based on the point at which the solvent becomes cloudy. The "HSP value of organic solvent (B4)" is a value calculated based on the molecular structure of organic solvent (B4). The "HSP value of surface treatment agent for conductive inorganic powder (B1)" is a value calculated based on the sedimentation velocity when conductive inorganic powder (B1) with the surface treatment agent applied is added to an organic solvent. As described above, the means of measuring the HSP value differs for each component in the technology disclosed herein. The reason for this is as follows. First, binder resin (A2) has a large molecular structure, making it difficult to calculate its HSP value based on molecular structure calculations; therefore, turbidity titration is required to measure its HSP value. On the other hand, in the technology disclosed herein, the HSP value of the surface treatment agent for conductive inorganic powder (B1) is controlled in order to suppress adhesion between the green sheet and the conductive inorganic powder (B1) via the surface treatment agent. Considering this objective, measuring the HSP value of the surface treatment agent before it is attached to the conductive inorganic powder (B1) is meaningless; it is necessary to measure the HSP value of the surface treatment agent after it has been attached to the surface of the conductive inorganic powder (B1). For this reason, in this specification, the HSP value of the surface treatment agent for conductive inorganic powder (B1) is measured based on the sedimentation velocity when the conductive inorganic powder (B1) with the surface treatment agent applied is added to an organic solvent.

[0052] As stated above, each paste used in the manufacturing kit disclosed herein may contain various organic components (such as photocurable resin (B2)) in addition to the binder resin (A2), organic solvent (B4), and conductive inorganic powder (B1) surface treatment agents. However, the HSP values ​​of these other organic components do not significantly affect the effects of the disclosed technology. For example, the disclosed technology ensures a sufficiently long development margin by appropriately generating a sheet attack in which the binder resin (A2) dissolves in the organic solvent (B4). Furthermore, the generation of residue is suppressed by inhibiting excessive sheet attack and preventing adhesion between the green sheet and the conductive inorganic powder (B1) via the surface treatment agent. Considering these mechanisms of action, it is understood that organic components other than the binder resin (A2), organic solvent (B4), and surface treatment agent do not significantly affect the effect of extending the development margin or suppressing residue.

[0053] 2. Manufacturing methods for electronic components Next, an embodiment of a method for manufacturing electronic components using the manufacturing kit disclosed herein will be described. Figures 1 to 3 are cross-sectional views illustrating each step of the manufacturing method for electronic components according to this embodiment. Note that the dimensional relationships (length, width, thickness, etc.) in these figures do not necessarily reflect actual dimensional relationships.

[0054] (1) Green sheet preparation process In this process, a green sheet is prepared by forming a substrate-forming paste (A) into a sheet. In this process, for example, the green sheet (see Figure 1) can be formed by applying the paste to the surface of a PET film (thickness of about 0.1 mm) using the doctor blade method. However, this process is not limited to the procedure described above, and the green sheet 10 can be formed using various methods. Alternatively, a pre-formed green sheet may be prepared separately.

[0055] (2) Membrane formation process In this process, a photosensitive conductive paste (B) is applied to the surface of the green sheet, and the photosensitive conductive paste (B) is dried. As a result, a film-like body 20 is formed on the surface of the green sheet 10, as shown in Figure 1. The appropriate drying temperature for this process is approximately 30°C to 60°C, and the appropriate drying time is approximately 5 to 20 minutes.

[0056] In this embodiment, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is adjusted to 2.5 or less. Therefore, when the photosensitive conductive paste (B) is applied to the surface of the green sheet 10, the organic solvent (B4) of the photosensitive conductive paste (B) dissolves into the green sheet 10, causing a sheet attack that dissolves the binder resin (A2) of the green sheet 10. As a result, the binder resin (A2) is distributed so as to straddle the boundary between the dried film-like body 20 and the green sheet 10, thereby improving the adhesion of the film-like body 20 to the surface of the green sheet 10.

[0057] (3) Exposure process As shown in Figure 2, in this process, a photomask M1 having a predetermined pattern of slits M1a is placed over the film-like body 20, and a portion of the film-like body 20 exposed through the slits M1a is exposed. As a result, the portion shielded by the photomask M1 remains as the film-like body 20, while the exposed portion directly below the slits M1a is photocured to become a photocured film 22. For this exposure process, an exposure machine that emits light in the wavelength range of 10 to 500 nm (typically ultraviolet light), such as an ultraviolet irradiation lamp such as a high-pressure mercury lamp, metal halide lamp, or xenon lamp, can be used.

[0058] (4)Developing process In this step, the uncured film-like material 20, which was shielded from light by the photomask, is removed with a developer. In this step, for example, a developing process is performed by spraying the developer onto the film-like material 20 and the photocured film 22 formed on the surface of the green sheet 10. The developing time (developer spraying time) at this time is set to a time such that the unexposed portion of the film-like material 20 is removed, and the exposed portion of the photocured film 22 remains. As a result, a photocured film 22 having a predetermined pattern is developed on the surface of the green sheet 10 (see Figure 3). An alkaline aqueous developer can be used as the developer. Examples of such aqueous developers include aqueous sodium hydroxide solution and aqueous sodium carbonate solution. The alkalinity of these aqueous developers should be adjusted to, for example, 0.01 to 0.5% by mass.

[0059] In this embodiment, the fixation of the photocured film 22 by sheet attack is improved in the film-forming process, so that peeling of the photocured film 22 during development can be appropriately prevented and a sufficient development margin can be secured. However, if the sheet attack occurs excessively, the fixation of the unexposed portion (film-like substance 20) increases, and the film-like substance 20 may remain on the surface of the green sheet 10 after development, becoming a residue. In response to this, in this embodiment, the HSP distance between the binder resin (A2) of the substrate forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is adjusted to 1.0 or more to prevent the occurrence of excessive sheet attack. Furthermore, if a surface treatment agent is applied to the particle surface of the conductive inorganic powder (B1), the conductive inorganic powder (B1) may adhere to the surface of the green sheet 10 via the surface treatment agent and become a residue. In contrast, in this embodiment, the HSP distance between the binder resin (A2) and the conductive inorganic powder (B1) surface treatment agent is adjusted to 1.0 or more to prevent the conductive inorganic powder (B1) from adhering via the surface treatment agent, which would cause residue generation.

[0060] (5) Firing process In this process, the green sheet 10 and the photocured film 22 remaining on the surface of the green sheet 10 are fired. This produces an electronic component having an insulating inorganic substrate and a linear conductive layer formed on the surface of the inorganic substrate in a predetermined pattern. The firing temperature in this process (the maximum temperature in the firing process) is preferably around 600°C to 1000°C.

[0061] As described above, the technology disclosed herein allows for the stable manufacture of electronic components with precise conductive layers, as it is possible to suitably suppress the generation of residue while ensuring a sufficiently long development margin. The manufactured electronic components can then be used, for example, as inductors, capacitors, multilayer circuit boards, etc. Typical examples of inductors include high-frequency inductors, common-mode filters, inductors (coils) for high-frequency circuits, inductors (coils) for general circuits, high-frequency filters, choke coils, transformers, etc. Furthermore, the shape (structure) of such electronic components is not particularly limited and may be surface-mount type or through-hole mounting type, etc. Also, the electronic components may be multilayer type with multiple conductive layers stacked on top of each other, or thin-film type with a single conductive layer.

[0062] [Example Test] The following describes test examples relating to the technology disclosed herein. However, the following description is not intended to limit the technology disclosed herein to those shown in the test examples.

[0063] 1. Sample preparation In this study, 26 different electronic component manufacturing kits (Test Examples 1-26) were prepared, each with different HSP values ​​for the binder resin (A2), organic solvent (B4), and surface treatment agent for the conductive inorganic powder (B1). The procedure for preparing each test example is described below.

[0064] (1) Preparation of paste (A) for base material formation First, as insulating inorganic powder (A1), alumina powder (D 50A particle size of 3 μm was prepared and weighed so that its content was 30% by mass relative to 100% by mass of paste. Next, three types of binder resins (resins a to c) shown in Table 1 below were prepared, and one of resins a to c below was used as binder resin (A2) in each of Test Examples 1 to 26. The binder resin (A2) used in each sample is shown in Table 4 below. The content of binder resin (A2) was standardized to 10% by mass in all of Test Examples 1 to 26. Then, the insulating inorganic powder (A1) and binder resin (A2) were mixed and ultrasonic dispersion was performed for 1 hour to prepare a paste (A) for substrate formation.

[0065] [Table 1]

[0066] (2) Preparation of photosensitive conductive paste (B) First, as conductive inorganic powder (B1), silver powder (D) with a surface treatment agent applied is used. 50 A particle size of 2.5 μm was prepared and weighed so that its content was 80% by mass relative to 100% by mass of the paste. In this test, three types of silver powder (silver powder a to c) with different surface treatment agents were prepared (see Table 2). Next, a (meth)acrylic resin (bifunctional acrylate) was prepared as the photocurable resin (B2) and weighed so that its content was 4.7% by mass. In addition, 2,4,6-trimethylbenzoyldiphenylphosphine oxide was prepared as the photopolymerization initiator (B3) and weighed so that its content was 0.12% by mass. Furthermore, in this test, six types of organic solvents (solvents a to f) shown in Table 3 below were prepared as the organic solvent (B4), and one of solvents a to f was used individually or in mixture so that the total content of organic solvent (B4) was 13.3% by mass. In addition, a cellulose resin (methylcellulose-based water-soluble resin) was prepared as the binder resin and weighed so that its content was 1.9% by mass. Then, after mixing the above-mentioned components, ultrasonic dispersion was performed for 1 hour to prepare a photosensitive conductive paste (B). The conductive inorganic powder (B1) and organic solvent (B4) used in each test example are shown in Table 4 below.

[0067] [Table 2]

[0068] [Table 3]

[0069] 2. Evaluation Test Electronic components with a conductive layer formed on the surface of an inorganic substrate were fabricated using 26 different manufacturing kits (Test Examples 1-26) that combined a substrate-forming paste (A) and a photosensitive conductive paste (B). Specifically, first, the substrate-forming paste (A) was molded into a sheet to create a green sheet measuring 50 mm wide x 75 mm long x 0.2 mm thick. Then, using screen printing, the photosensitive conductive paste was applied to the surface of the green sheet in a 20 mm wide x 20 mm long x 32 μm thick area, followed by a drying treatment at 55°C for 10 minutes to form a film. Finally, a photomask with a predetermined pattern of slits was placed over the film, and an illuminance of 30 mW / cm² was applied. 2 , exposure amount 300mJ / cm 2 Light was irradiated under these conditions, exposing the film-like material located directly below the slit to create a photocured film. In this test, a photomask was used with the slit's L / S (line / space) set to 15 μm / 15 μm.

[0070] Next, a developing process was carried out to remove the film-like substance on the green sheet using a developer. In this process, the developer (0.1% by mass Na2CO3 aqueous solution) was continuously sprayed onto the film-like substance on the green sheet for a predetermined developing time. Specifically, after measuring the developing time at which the film-like substance on the green sheet was completely removed (breakpoint), the developing process was continued until peeling or breakage occurred in the photocured film. The time from the breakpoint to the point at which peeling or breakage was confirmed was considered the "developing margin," and the length of this developing margin was evaluated. The evaluation results are shown in the "Developing Margin Evaluation" column in Table 4. The evaluation criteria for the "Developing Margin Evaluation" in Table 4 are as follows. "×": Peeling or other damage occurred to the photocured film within 3 seconds of the breakpoint. "△": Peeling or other damage occurred to the photocured film between 3 seconds and 7 seconds after the breakpoint. "○": No peeling or other damage occurred to the photocured film even after more than 7 seconds had elapsed since the breakpoint.

[0071] Next, in each test example, samples were prepared in which the development process was completed within the development margin range described above. These samples were then observed with an optical microscope, and the number of residues adhering to the space between adjacent photocured films was counted. The average number of residues across three fields of view was calculated, and the residue suppression performance in each test example was evaluated based on the calculation results. The results are shown in the "Residue Evaluation" column of Table 4. The evaluation criteria used in this evaluation are as follows. "×": The average number of residues was 4 or more. "○": The average number of residues was 3 or less.

[0072] [Table 4]

[0073] As shown in Table 4 above, the development margin evaluation results showed that a development margin of 3 seconds or more could be secured in test examples 1-3, 5-7, 9-11, 13-15, 17, 18, and 20-25. From this, it was found that a sufficient development margin can be secured by setting the HSP distance between the organic solvent (B4) of the photosensitive conductive paste (B) and the binder resin (A2) of the substrate forming paste (A) to 2.5 or less. This is presumed to be because the binder resin (A2) became more easily soluble in the organic solvent (B4), resulting in appropriate sheet attack on the green sheet. Furthermore, a comparison of test examples 10 and 13 confirmed that an even longer development margin can be secured by setting the HSP distance between the surface treatment agent of the conductive inorganic powder (B1) and the binder resin (A2) to 3.5 or less.

[0074] Next, the residue evaluation results showed that in test examples 2, 4-6, 8, 10, 12-14, 16, 17, 19-24, and 26, the average number of residue particles after development was suppressed to 3 or less. From this, it was found that the generation of residue can be suitably suppressed by setting the HSP distance between the organic solvent (B4) and the binder resin (A2) to 1.0 or more, and also by setting the HSP distance between the conductive inorganic powder (B1) surface treatment agent and the binder resin (A2) to 1.0 or more. This is presumed to be because it prevents excessive sheet attack caused by making the HSP distance between the organic solvent (B4) and the binder resin (A2) too close, and prevents the conductive inorganic powder (silver powder) from adhering to the surface of the green sheet via the surface treatment agent.

[0075] Furthermore, the results of this test showed that for the effects of the technology disclosed herein to be properly realized, it is sufficient that the HSP distance between the organic solvent (B4) and the binder resin (A2), and the HSP distance between the surface treatment agent and the binder resin (A2) are properly adjusted, and that the specific types and structures of the binder resin (A2), organic solvent (B4), and surface treatment agent do not significantly affect the effects of the technology disclosed herein.

[0076] Although the present invention has been described in detail above, these are merely examples, and the present invention can be modified in various ways without departing from its spirit. [Explanation of symbols]

[0077] 10 Green Sheets 20 Membrane 22 Photocured film

Claims

1. A kit for producing electronic components, comprising: a base-forming paste (A) for forming an insulating inorganic base; and a photosensitive conductive paste (B) for forming a conductive layer on the surface of the inorganic base, The substrate-forming paste (A) is an insulating inorganic powder (A1); Binder resin (A2) Including, The photosensitive conductive paste (B) is A conductive inorganic powder (B1) having a surface treatment agent attached to the particle surface; a photocurable resin (B2), a photopolymerization initiator (B3), and Organic solvent (B4) Including, The HSP distance between the binder resin (A2) of the base material forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is 1.0 or more and 2.5 or less, and The kit for producing electronic components, wherein the HSP distance between the binder resin (A2) of the base material-forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is 1.0 or more.

2. 2. The electronic component manufacturing kit according to claim 1, wherein the HSP distance between the binder resin (A2) of the base material forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is 3.5 or less.

3. 3. The kit for producing electronic components according to claim 1, wherein the binder resin (A2) has an HSP value of 17.0 to 22.

0.

4. The kit for producing electronic components according to any one of claims 1 to 3, wherein the organic solvent (B4) has an HSP value of 17.0 to 21.

0.

5. The kit for producing electronic components according to any one of claims 1 to 4, wherein the HSP value of the surface treatment agent for the conductive inorganic powder (B1) is 17.5 to 21.

0.

6. The kit for producing electronic components according to any one of claims 1 to 5, wherein the conductive inorganic powder (B1) contains silver-based particles.

7. A photosensitive conductive paste used in the kit for producing electronic components according to any one of claims 1 to 6, The conductive inorganic powder (B1) has a surface treatment agent attached to its surface, the photocurable resin (B2), the photopolymerization initiator (B3), and the organic solvent (B4), The HSP distance between the binder resin (A2) of the base material forming paste (A) and the organic solvent (B4) of the photosensitive conductive paste (B) is 1.0 or more and 2.5 or less, and A photosensitive conductive paste, wherein the HSP distance between the binder resin (A2) of the base material forming paste (A) and the surface treatment agent of the conductive inorganic powder (B1) of the photosensitive conductive paste (B) is 1.0 or more.

8. A method for manufacturing an electronic component using the electronic component manufacturing kit according to any one of claims 1 to 6, comprising: a green sheet preparation step of preparing a green sheet by forming the base material forming paste (A) into a sheet; a film-like body forming step of applying the photosensitive conductive paste (B) to the surface of the green sheet and drying the photosensitive conductive paste (B) to form a film-like body; an exposure step of covering the film-like body with a photomask having slits of a predetermined pattern and irradiating light onto a portion of the film-like body exposed through the slits to form a photocured film; a developing step of removing the uncured film-like body that was shielded from light by the photomask with a developer; a firing step of firing the green sheet and the photocured film remaining on the surface of the green sheet; A method for manufacturing an electronic component, comprising:

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