JP6814237B2 - Photosensitive compositions and their use - Google Patents

Description

The present invention relates to a photosensitive composition and its use.

Conventionally, a method of forming a conductive layer on a substrate by a photolithography method using a photosensitive composition containing a photosensitive component and a photopolymerization initiator has been known (see Patent Documents 1 to 7). In such a method, for example, first, a photosensitive composition is applied onto a substrate and dried to form a film-like body (step of molding the film-like body). Next, the molded film-like body is covered with a photomask having a predetermined opening pattern, and the film-like body is exposed through the photomask (exposure step). As a result, the exposed portion of the film-like body is photocured. Next, the unexposed portion that has been shielded from light by the photomask is corroded and removed with an alkaline aqueous developer (development step). Then, the film-like body having a desired pattern is fired (firing step). According to the photolithography method including the above steps, a finer conductive layer can be formed as compared with various conventional printing methods.

Japanese Unexamined Patent Publication No. 2000-199954 JP-A-2002-072472 Japanese Unexamined Patent Publication No. 2006-344590 Japanese Unexamined Patent Publication No. 2014-170051 International Publication 2015-151892 Japanese Unexamined Patent Publication No. 2016-180908 Japanese Unexamined Patent Publication No. 2016-201104

By the way, in recent years, various electronic devices have been rapidly miniaturized and improved in performance, and electronic components mounted on the electronic devices are also required to be further miniaturized and have a higher density. Along with this, in the manufacture of electronic components, it is required to reduce the resistance of the conductive layer and to make the wire thinner (narrower). More specifically, for example, a line representing the ratio of the line width of the wiring to the interval portion of the adjacent line by forming a thick conductive layer to reduce the resistance and improving the resolution of the pattern. It is required to form a fine-line conductive layer having an and space (L / S) of 20 μm / 20 μm or less.

However, according to the study by the present inventors, when the conductive layer is thickened or when an attempt is made to form the conductive layer with a small L / S as described above, the developability tends to decrease and a desired pattern is stably formed. It's difficult. As an example, when the thickness of the conductive layer is increased, the curing of the deep portion close to the base material becomes insufficient, and peeling or disconnection of the conductive film is likely to occur in the developing process. Further, if the L / S is small, it becomes difficult to supply the developer to the space between the lines in the developing process. As a result, the development time, that is, the time required to completely remove the unexposed portion (time until the breakpoint (BP)) becomes long, or the residue that cannot be completely removed remains in the space portion. I may do it.

The present invention has been made in view of the above points, and an object of the present invention is to provide a photosensitive composition having excellent developability and resolvability. Another related object is to provide a composite comprising a conductive film made of a dried product of such a photosensitive composition. Another related object is to provide an electronic component including a conductive layer made of a fired body of such a photosensitive composition, and a method for producing the same.

According to the present invention, a photosensitive composition containing a conductive powder, a cellulosic organic binder, a (meth) acrylic photocurable resin having an acid value, a photopolymerizable compound, and a photopolymerization initiator. Is provided. This photosensitive composition is obtained when the total of the cellulosic organic binder, the (meth) acrylic photocurable resin having an acid value, and the photopolymerizable compound is 100% by mass. The content of the cellulosic organic binder is 10 to 40% by mass; the content of the (meth) acrylic photocurable resin having the acid value is 5 to 40% by mass; the content of the photopolymerizable compound is 30 to 60% by mass;

In the above photosensitive composition, three kinds of organic components, that is, a cellulose-based organic binder, a (meth) acrylic-based photocurable resin having an acid value, and a photopolymerizable compound are appropriately balanced. There is. As a result, in the developing process, the unexposed portion can be easily removed, the developing time can be shortened, and the generation of residue can be reduced. In addition, it becomes easy to cure to a deep part (a part close to the base material) of the exposed part, the adhesion between the base material and the exposed part can be improved, and the occurrence of peeling and disconnection can be suppressed. As a result, the above-mentioned photosensitive composition can suitably form a fine-line conductive layer having an L / S of 20 μm / 20 μm or less.

In a preferred embodiment disclosed herein, the cellulosic organic binder has an acid value of 20 mgKOH / g or higher. As a result, the unexposed portion can be removed more quickly and cleanly in the developing process.

In a preferred embodiment disclosed here, the acid value of the (meth) acrylic photocurable resin having the above acid value is 50 mgKOH / g or more and 150 mgKOH / g or less. As a result, the removability of the unexposed portion and the etching resistance of the exposed portion can be balanced at a higher level. That is, in the developing step, the unexposed portion can be removed more quickly and cleanly, and peeling and disconnection of the exposed portion can be better suppressed.

In a preferred embodiment disclosed here, the weight average molecular weight of the (meth) acrylic photocurable resin having the above acid value is 10,000 or more and 30,000 or less. As a result, even with a small amount of exposure, the exposed portion can be suitably cured to a deep part.

In a preferred embodiment disclosed here, the total of the cellulosic organic binder, the (meth) acrylic photocurable resin having an acid value, and the photopolymerizable compound is set to 100% by mass. Occasionally, the content of the cellulosic organic binder is 20 to 35% by mass; the content of the (meth) acrylic photocurable resin having the acid value is 10 to 30% by mass; of the photopolymerizable compound. The content ratio is 50 to 60% by mass; Thereby, the developability and / or the resolvability can be further improved, and the effect of the technique disclosed herein can be exhibited at a higher level.

In a preferred embodiment disclosed herein, the conductive powder comprises silver-based particles. As a result, it is possible to realize a conductive layer having an excellent balance between cost and low resistance.

The present invention also provides a composite comprising a green sheet and a conductive film arranged on the green sheet and made of a dried product of the photosensitive composition.

Further, the present invention provides an electronic component including a conductive layer made of a fired body of the photosensitive composition. According to the above-mentioned photosensitive composition, a fine-line conductive layer having a small L / S can be formed with good reproducibility. Therefore, by using the above-mentioned photosensitive composition, it is possible to preferably realize an electronic component having a small size and / or a high-density conductive layer.

Further, according to the present invention, an electron including a step of applying the photosensitive composition onto a substrate, exposing and developing the mixture, and then firing the mixture to form a conductive layer made of a fired body of the photosensitive composition. A method of manufacturing parts is provided. By such a manufacturing method, an electronic component provided with a small and / or high-density conductive layer can be stably manufactured, and productivity and yield can be improved.

It is sectional drawing which shows typically the structure of the laminated chip inductor which concerns on one Embodiment. It is an optical microscope image of the wiring pattern of Example 1.

Hereinafter, preferred embodiments of the present invention will be described. It should be noted that matters other than those specifically mentioned in the present specification (for example, the composition of the photosensitive composition) and necessary for carrying out the present invention (for example, the method for preparing the photosensitive composition, the conductive film and the conductive layer). Method of forming, electronic component manufacturing method, etc.) can be understood based on the technical contents taught in this specification and the general technical common sense of those skilled in the art in the art. The present invention can be carried out based on the contents disclosed in the present specification and common general technical knowledge in the art.

In the following description, a film-like body (dried product) obtained by drying the photosensitive composition at a temperature below the boiling point of the organic component, specifically, at about 200 ° C. or lower, for example, 100 ° C. or lower, is referred to as a "conductive film". .. The conductive film includes all unfired (before firing) film-like bodies. The conductive film may be an uncured product before photo-curing or a cured product after photo-curing. Further, in the following description, a sintered body (calcined product) obtained by firing the photosensitive composition at a temperature equal to or higher than the sintering temperature of the conductive powder is referred to as a “conductive layer”. The conductive layer includes a wiring (linear body), a wiring pattern, and a solid pattern.
Further, in the present specification, the notation of "A to B" (A and B are arbitrary numbers) indicating the range means "preferably larger than A" and "preferably smaller than B" with the meaning of A or more and B or less. It shall include the meaning of.

≪Photosensitive composition≫
The photosensitive composition disclosed herein can be suitably used for producing, for example, a conductive layer including wiring of a fine line having an L / S of 20 μm / 20 μm or less, particularly an ultrafine line having an L / S of 15 μm / 15 μm or less. .. The photosensitive composition disclosed herein contains (A) a conductive powder, (B) an organic binder, (C) a photocurable resin, (D) a photopolymerizable compound, and (D) as essential components. E) Contains a photopolymerization initiator. Hereinafter, each component will be described in order.

<(A) Conductive powder>
The conductive powder is, for example, a component that imparts electrical conductivity to a conductive layer obtained by firing a photosensitive composition. The conductive powder is not particularly limited, and from among conventionally known powders, for example, one type may be used alone or two or more types may be used in combination depending on the intended use. Preferable examples of the conductive powder are gold (Au), silver (Ag), copper (Cu), platinum (Pt), palladium (Pd), aluminum (Al), nickel (Ni), ruthenium (Ru), rhodium ( Examples thereof include simple metals such as Rh), tungsten (W), iridium (Ir), and osmium (Os), and mixtures and alloys thereof. Examples of the alloy include silver alloys such as silver-palladium (Ag-Pd), silver-platinum (Ag-Pt), and silver-copper (Ag-Cu).

In a preferred embodiment, the conductive powder comprises silver-based particles. Silver is relatively inexpensive and has high electrical conductivity. Therefore, when the conductive powder contains silver-based particles, it is possible to realize a conductive layer having an excellent balance between cost and low resistance.
In addition, in this specification, "silver-based particles" include all those containing a silver component. Examples of silver-based particles include simple silver, the above-mentioned silver alloy, and core-shell particles having silver-based particles as a core, for example, silver-ceramic core-shell particles and the like.

Although not particularly limited, (in volume-based particle size distribution based on the laser diffraction scattering method, a particle diameter corresponding the small particle size side on the integrated value _50%.) D 50 particle size of the conductive powder , It is preferably about 0.1 to 5 μm. D ₅₀ particle size to within the above range, to improve the exposure performance of the exposure portion, it is possible to form a fine line even more stably. By suppressing the aggregation of a photosensitive composition, from the viewpoint of improving the stability, D ₅₀ particle size of the conductive powder is, for example, 0.5 [mu] m or more, it may be 1μm or more. You can also increase the fine wire forming, in view of or promoting densification and low resistance of the conductive layer, D ₅₀ particle size of the conductive powder is, for example, 4.5 [mu] m or less, even 4μm or less Good.

An organic surface treatment agent may be attached to the surface of the conductive powder. The organic surface treatment agent, for example, improves the dispersibility of the conductive powder in the photosensitive composition, enhances the affinity between the conductive powder and other contained components, and surface oxidizes the metal constituting the conductive powder. It can be used for at least one of the purposes of preventing. Examples of the organic surface treatment agent include fatty acids such as carboxylic acids and benzotriazole compounds.

Although not particularly limited, the proportion of the conductive powder in the entire photosensitive composition is approximately 50% by mass or more, typically 60% by mass or more, for example 70% by mass or more, and 80% by mass or more in one example. It is preferable that the content is approximately 95% by mass or less, for example, 90% by mass or less and 85% by mass or less. By satisfying the above range, a conductive layer having excellent density and electrical conductivity can be suitably formed. In addition, the handleability of the photosensitive composition and the workability when molding the conductive film can be improved.

<(B) Organic binder>
The organic binder is a component that enhances the adhesiveness between the base material and the conductive film (uncured product) before photocuring. Further, the photosensitive composition containing (C) a photocurable resin, which will be described later, has a trade-off that the developing time becomes long. Therefore, in the technique disclosed herein, the organic binder is a component for compensating for the above-mentioned conflicts and shortening the developing time and improving the developability. Unlike the (C) photocurable resin and (D) photopolymerizable compound described later, the organic binder does not have photosensitivity (for example, photocurability). In the present embodiment, the organic binder is composed of a cellulosic compound. By containing the cellulosic compound, (A) the conductive powder can be easily blended with (C) a photocurable resin and (D) a photopolymerizable compound described later, and the storage stability of the photosensitive composition is improved. can do. Further, since the cellulosic compound typically has a plurality of hydroxyl groups in the glucose ring, which is a repeating constituent unit of cellulose, and exhibits good water solubility, it can be easily removed with an aqueous developer in the developing step. it can.

Cellulosic compounds include celluloses, cellulosic derivatives, and salts thereof. As the cellulosic compound, one of the conventionally known compounds can be used alone, or two or more thereof can be used in combination as appropriate. As one preferable example of the cellulosic compound, hydroxyalkyl cellulose such as hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose; alkyl cellulose such as methyl cellulose and ethyl cellulose; carboxyalkyl cellulose such as carboxymethyl cellulose; and the like can be mentioned.

When an alkaline aqueous developer is used in the development process, the cellulose-based compound has highly alkaline-soluble structural parts, such as acidic groups such as phenolic hydroxyl groups, carboxyl groups, sulfo groups, phosphono groups and boronic acid groups. It is good to do it. Of these, a carboxyl group is preferable. An acidic group is a substituent having a dissociative proton and showing acidity in water. The acidic group may be partially esterified. The acidic group may be bonded to the carbon atom of the main chain (the carbon chain having the maximum number of carbon atoms; the same applies hereinafter) of the cellulosic compound, and the side chain (the carbon chain branched from the main chain; the same applies hereinafter). It may be bonded to the carbon atom of.). By including a structural portion having a high alkali solubility, it becomes easier to remove the unexposed portion more quickly and without residue with an alkaline aqueous developer.

In a preferred embodiment, the cellulosic compound has an acid value. The acid value of the cellulosic compound is approximately 10 mgKOH / g or more, preferably 20 mgKOH / g or more, more preferably 25 mgKOH / g or more, for example 30 mgKOH / g or more, and is typically a (meth) acrylic-based compound described later. It is smaller than the photocurable resin and is generally 150 mgKOH / g or less, preferably 100 mgKOH / g or less, for example 75 mgKOH / g or less, and in one example, 50 mgKOH / g or less. The acid value of the entire organic binder is more preferably in the above range. In other words, it is preferable that the entire organic binder exhibits a predetermined acidity. When the acid value is at least a predetermined value, the removability of the unexposed portion is enhanced in the developing step, and the developability can be further improved. Further, when the acid value is not more than a predetermined value, the solubility in an aqueous developer is suppressed, and peeling or disconnection of an exposed portion can be better suppressed in the developing process. Therefore, the effects of the techniques disclosed herein can be exerted at a higher level.
In the present specification, the "acid value" is the content (mg) of potassium hydroxide (KOH) required to neutralize the free fatty acid contained in the unit sample (1 g). The unit is mgKOH / g.

In a preferred embodiment, the cellulosic compound comprises a cellulosic polymer compound having a weight average molecular weight of 5000 or more. By containing the cellulosic polymer compound, the adhesiveness (tack property) of the conductive film before photocuring to the base material is enhanced, and it is possible to suitably suppress the occurrence of defects such as peeling and disconnection in the conductive layer. .. The cellulosic polymer compound may contain an acidic group as a repeating structural unit. Further, the weight average molecular weight of the cellulosic polymer compound is preferably larger than that of the (meth) acrylic-based photocurable resin described later. For example, it is preferable that the weight average molecular weight of the (meth) acrylic photocurable resin is approximately twice or more, for example, three times or more. The weight average molecular weight of the cellulosic polymer compound is approximately 10,000 or more, typically 20,000 or more, for example, 50,000 or more, and in one example, 100,000 or more, approximately 1 million or less, typically 500,000 or less. For example, it may be 200,000 or less.
In addition, in this specification, "weight average molecular weight" means weight-based average molecular weight measured by gel permeation Chromatography (GPC) and converted using the standard polystyrene calibration curve.

The organic binder may be composed of only the above-mentioned cellulosic compounds, and can be conventionally used in this kind of application in addition to the cellulosic compounds as long as the effects of the techniques disclosed herein are not significantly reduced. It may contain other known compounds. Examples of such a compound include acrylic resin, phenol resin, epoxy resin, polyester resin, polyamide resin, polycarbonate resin and the like. The proportion of the cellulosic compound in the entire organic binder is preferably about 50% by mass or more, typically 80% by mass or more, for example 90% by mass or more, substantially 100% by mass (95% by mass). % Or more).

Although not particularly limited, the proportion of the organic binder in the entire photosensitive composition is typically lower than that of the (D) photopolymerizable compound described later, and is generally 0.1 to 20% by mass, which is typical. It is preferable that the content is 0.5 to 10% by mass, for example, 1 to 5% by mass. By setting the ratio of the organic binder to a predetermined value or more, the developability can be improved and the development time can be shortened in the development process. In addition, the holding power (etching resistance) of the photosensitive composition with respect to the substrate is enhanced, and peeling and disconnection of the exposed portion can be better suppressed. By setting the ratio of the organic binder to a predetermined value or less, the ratio of the photosensitive component, that is, the ratio of the (C) photocurable resin and (D) photopolymerizable compound described later is relatively improved, and in the exposure step, The conductive film before photocuring can be cured more stably.

<(C) Photocurable resin>
A photocurable resin is a photocurable component that is cured by causing a polymerization reaction, a cross-linking reaction, or the like by light irradiation. The photocurable resin can be cured with a smaller exposure amount than the (D) photopolymerizable compound described later. Therefore, in the technique disclosed herein, the photocurable resin is a photocurable component for steadily curing a deep portion (a portion close to the substrate) of the exposed portion. The polymerization reaction may be, for example, addition polymerization or ring-opening polymerization. In the present specification, the photocurable resin includes a polymer and an oligomer (prepolymer) except for a monomer. Photocurable resins typically have one or more unsaturated bonds and / or cyclic structures. The unsaturated bond and / or the cyclic structure may be bonded to the carbon atom of the main chain of the photocurable resin, or may be bonded to the carbon atom of the side chain.

In the present embodiment, the photocurable resin contains a (meth) acrylic photocurable resin (hereinafter, also referred to as (meth) acrylic resin) having a monomer having a (meth) acryloyl group as a constituent unit. There is. By containing the (meth) acrylic resin, the flexibility of the conductive layer and the followability to the base material can be improved, and the occurrence of peeling and disconnection can be better suppressed. In addition, the durability of the conductive layer can be improved.
In addition, in this specification, "(meth) acryloyl group" means "methacryloyl group (-C (= O) -C (CH ₃ ) = CH ₂ )" and "acryloyl group (-C (= O)-". "CH = CH ₂ )" and "(meth) acrylate" are terms that include "methacrylate" and "acrylate".

As the (meth) acrylic resin, one of the conventionally known resins can be used alone, or two or more thereof can be used in combination as appropriate. As a preferred example of the (meth) acrylic resin, a homopolymer of an alkyl (meth) acrylate or a copolymer containing an alkyl (meth) acrylate as a main monomer and a copolymer having a copolymerizable submonomer in the main monomer is used. Can be mentioned. Among them, a (meth) acrylic resin having a (meth) acryloyl group (preferably acryloyl group) in the side chain is preferable from the viewpoint of improving the photocurability.

Specific examples of the homopolymer include polymethyl (meth) acrylate, polyethyl (meth) acrylate, polybutyl (meth) acrylate and the like. Specific examples of the copolymer include, for example, a block copolymer containing a polymer of a methacrylic acid ester and a polymer block of an acrylic acid ester as a repeating constituent unit. Specific examples of the methacrylic acid ester include methyl methacrylate, propyl methacrylate, n-butyl methacrylate, t-butyl methacrylate and the like. Specific examples of the acrylic acid ester include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, t-butyl acrylate, n-hexyl acrylate and the like.

In the present embodiment, the (meth) acrylic resin contains a monomer unit derived from an acidic group-containing monomer having an acidic group. For example, in addition to the (meth) acryloyl group, it further contains a monomer unit containing at least one of a phenolic hydroxyl group, a carboxyl group, a sulfo group, a phosphono group and a boronic acid group. As a result, the removability of the uncured portion can be effectively enhanced in the developing step, the developability can be enhanced, and the developing time can be shortened. The acidic group may be bonded to a carbon atom in the main chain or a carbon atom in the side chain.

Specific examples of the (meth) acrylic resin include a carboxyl group-containing (meth) acrylic resin, a phosphono group-containing (meth) acrylic resin, an acid-modified epoxy (meth) acrylic resin, and a carboxyl group-containing urethane-modified epoxy. Examples include (meth) acrylic resins. Among them, it is preferable to contain a (meth) acrylic resin containing a (meth) acryloyl group and a carboxyl group. Examples of commercially available (meth) acrylic resins having an acidic group include Cyclomer P ™ ACA Z200M, Z230AA, Z250, Z251, Z300, Z320, and Z254F manufactured by Daicel Ornex Co., Ltd.

In the present embodiment, the (meth) acrylic resin has an acid value. The resin acid value of the (meth) acrylic resin is approximately 30 mgKOH / g or more, typically 40 mgKOH / g or more, preferably 50 mgKOH / g or more, for example 60 mgKOH / g or more, and 80 mgKOH / g or more in one example. It is generally 300 mgKOH / g or less, typically 200 mgKOH / g or less, preferably 150 mgKOH / g or less, for example 135 mgKOH / g or less, and in one example 100 mgKOH / g or less. It is more preferable that the resin acid value of the entire photocurable resin is in the above range. In other words, it is preferable that the entire photocurable resin exhibits a predetermined acidity. When the resin acid value is equal to or higher than a predetermined value, the unexposed portion can be removed more quickly and cleanly in the developing step. Further, when the resin acid value is not more than a predetermined value, the solubility in an aqueous developer is suppressed, and peeling or disconnection of an exposed portion can be better suppressed in the developing process.

In a preferred embodiment, the photocurable resin comprises a polymer having a weight average molecular weight of 5000 or more. When the photocurable resin contains a polymer, the adhesion to the substrate is increased, and the developing time tends to be long or the developability tends to be lowered in the developing process. Therefore, the application of the techniques disclosed herein is effective. The weight average molecular weight of the photocurable resin is usually larger than that of the photopolymerizable compound described later and smaller than the weight average molecular weight of the cellulosic organic binder. Specifically, it is approximately 7,000 or more, preferably 10,000 or more, for example, 14,000 or more, in one example, 15,000 or more, 20,000 or more, approximately 100,000 or less, typically 50,000 or less, preferably 50,000 or less. It should be 30,000 or less. As a result, the exposed portion can be suitably cured to the deep part even with a small amount of exposure.

In one preferred embodiment, the double bond equivalent of the (meth) acrylic resin (weight average molecular weight / calculated value calculated by the number of C = C double bonds) is approximately 200 or more, typically 300 or more. Further, it is 350 or more, for example, 380 or more, and is approximately 1500 or less, typically 1200 or less, for example, 1100 or less. When the double bond equivalent is in the above range, the removability of the unexposed portion and the etching resistance of the exposed portion can be balanced at a high level in the developing step. That is, the development time can be shortened better, and the occurrence of peeling and disconnection can be better suppressed.

In one preferred embodiment, the glass transition point (Tg value based on Differential Scanning Calorimetry (DSC)) of the (meth) acrylic resin is approximately 40 ° C. or higher, typically 50 ° C. or higher, for example. It is 60 ° C. or higher, further 100 ° C. or higher, 120 ° C. or higher, 130 ° C. or higher in one example, and generally 200 ° C. or lower, for example 150 ° C. or lower. As a result, the flexibility and adhesiveness of the exposed portion can be further enhanced, and the occurrence of peeling and disconnection can be better suppressed. Further, when the Tg value is in the above range, the adhesiveness of the conductive film before photocuring to the substrate is increased, and the removability of the unexposed portion is lowered in the developing step. Therefore, the application of the techniques disclosed herein is effective.

The photocurable resin may be composed of only the (meth) acrylic resin described above, and in addition to the (meth) acrylic resin, this type has been conventionally used as long as the effect of the technique disclosed herein is not significantly reduced. Other resins known to be usable in the above applications may be included. The ratio of the (meth) acrylic resin to the total amount of the photocurable resin is preferably about 50% by mass or more, typically 80% by mass or more, for example 90% by mass or more, substantially 100. It may be mass% (95 mass% or more).

Although not particularly limited, the proportion of the photocurable resin in the entire photosensitive composition is typically lower than that of the (D) photopolymerizable compound described later, and is approximately 0.1 to 50% by mass. Typically, it is 0.5 to 30% by mass, for example, 1 to 20% by mass, and more preferably 2 to 10% by mass. By setting the ratio of the photocurable resin to a predetermined value or more, the exposed portion can be accurately cured to the deep part, and peeling and disconnection of the exposed portion can be better suppressed. By setting the ratio of the photocurable resin to a predetermined value or less, the ratio of (B) an organic binder and (D) a photopolymerizable compound described later is relatively improved, the developability is further improved, and the developing time is improved. Can be further shortened.

Although not particularly limited, when the total of the polymer components, that is, the total of (B) the organic binder and (C) the photocurable resin ((B) + (C)) is 100% by mass, ( C) The content ratio of the photocurable resin is approximately 5% by mass or more, preferably 10% by mass or more, more preferably 20% by mass or more, in one example, 30% by mass or more, 35% by mass or more, and approximately 90% by mass. % Or less, preferably 70% by mass or less, more preferably 65% by mass or less, and in one example, 60% by mass or less, 50% by mass or less. As a result, the effect of improving the developability by using the organic binder and the effect of preventing peeling by using the photocurable resin can be stably achieved at a higher level.

<(D) Photopolymerizable compound>
The photopolymerizable compound is a photocurable component that is cured by causing a polymerization reaction, a cross-linking reaction, or the like due to an active species generated by decomposition of the photopolymerization initiator (E) described later. Further, in the technique disclosed herein, the photopolymerizable compound is a photocurable component for completing curing in a short development time. A photopolymerizable compound is a monomer having one or more polymerizable functional groups. The photopolymerizable compound includes a monofunctional monomer having one polymerizable functional group per molecule, a polyfunctional monomer having two or more polymerizable functional groups per molecule, and modified products thereof. Photopolymerizable compounds typically have one or more unsaturated bonds and / or cyclic structures. As a preferred example of the photopolymerizable compound, a radically polymerizable monomer having one or more unsaturated bonds such as a (meth) acryloyl group or a vinyl group, or a cationically polymerizable monomer having a cyclic structure such as an epoxy group. Can be mentioned.

In a preferred embodiment, the photopolymerizable compound comprises a (meth) acrylate monomer having a (meth) acryloyl group. As a result, the affinity with the (meth) acrylic-based photocurable resin is enhanced, and the storage stability of the photosensitive composition can be improved. As a preferable example of the (meth) acrylate monomer, triethylene glycol monoacrylate, triethylene glycol monomethacrylate, tetraethylene glycol monoacrylate, tetraethylene glycol monomethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol pentaacrylate. , Dipentaerythritol hexaacrylate, tripentaerythritol heptaacrylate, tripentaerythritol octaacrylate, tetrapentaerythritol nonaacrylate, tetrapentaerythritol decaacrylate and the like. Among them, from the viewpoint of enhancing photocurability, a monomer having 3 or more, more preferably 5 or more (meth) acryloyl groups per molecule is preferable.

In another preferred embodiment, the photopolymerizable compound comprises a urethane bond-containing compound having a urethane bond (-NH-C (= O) -O-). By containing the urethane bond-containing compound, it is possible to better improve the etching resistance of the exposed portion and to realize a conductive layer having further excellent flexibility and elasticity. Therefore, the adhesion between the base material and the conductive layer can be improved, and the occurrence of peeling and disconnection can be suppressed at a high level. As a preferable example of the urethane bond-containing compound, urethane-modified (meth) acrylate in which the above-mentioned (meth) acrylate monomer contains a urethane bond, urethane-modified epoxy, and the like can be mentioned.

Although not particularly limited, the weight average molecular weight of the photopolymerizable compound is usually smaller than that of the above-mentioned cellulosic organic binder or (meth) acrylic photocurable resin, and is generally 2000 or less, typically 2000 or less. It is preferably 100 to 1500, for example, 500 to 1300.

Although not particularly limited, the proportion of the photopolymerizable compound in the entire photosensitive composition is typically higher than that of (B) organic binder and (C) photocurable resin, and is generally 0.1 to 0.1. It is preferably 50% by mass, typically 0.5 to 30% by mass, for example 1 to 20% by mass, and further 2 to 10% by mass. By setting the ratio of the photopolymerizable compound to a predetermined value or more, the developability can be improved and the development time can be further shortened. By setting the ratio of the photopolymerizable compound to a predetermined value or less, the ratio of the polymer component, that is, the ratio of (B) organic binder and (C) photocurable resin is relatively improved, and the photosensitive composition with respect to the substrate is relatively improved. The holding power of is enhanced. As a result, peeling and disconnection of the exposed portion can be better suppressed.

Although not particularly limited, when the total of photosensitive components, that is, the total of (C) photocurable resin and (D) photopolymerizable compound ((C) + (D)) is 100% by mass. In addition, the content ratio of the (D) photopolymerizable compound is preferably higher than that of the (C) photocurable resin. Specifically, the content ratio of the (D) photopolymerizable compound exceeds 50% by mass, preferably 55% by mass or more, more preferably 60% by mass or more, and in one example, 65% by mass or more, 70% by mass or more. It is preferable that the content is approximately 95% by mass or less, preferably 90% by mass or less, more preferably 85% by mass or less, and in one example, 80% by mass or less. As a result, the effect of preventing peeling by using the photocurable resin and the effect of shortening the development time by using the photopolymerizable compound can be stably achieved at a higher level.

<(E) Photopolymerization Initiator>
The photopolymerization initiator is a component that is decomposed by irradiation with light energy such as ultraviolet rays to generate active species such as radicals and cations to initiate the polymerization reaction of the photopolymerizable compound. As the photopolymerization initiator, one of the conventionally known ones may be used alone or two or more thereof may be appropriately combined depending on the type of the photosensitive resin and the like. As one preferred example, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane Examples thereof include -1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4-diethylthioxanthone, and benzophenone.

Although not particularly limited, the proportion of the photopolymerization initiator in the entire photosensitive composition is approximately 0.01 to 5% by mass, typically 0.1 to 3% by mass, for example, 0.2 to 3. It is preferably 2% by mass. As a result, the photocurability of the photosensitive composition is sufficiently exhibited, and the conductive layer can be formed more stably.

<(F) Organic dispersion medium>
In addition to the above-mentioned essential components, the photosensitive composition may contain an organic dispersion medium for dispersing these components. The organic dispersion medium is a component that imparts appropriate viscosity and fluidity to the photosensitive composition to improve the handleability of the photosensitive composition and improve the workability when molding the conductive film. is there. As the organic dispersion medium, one of the conventionally known ones may be used alone or two or more thereof may be appropriately combined depending on the type of the photopolymerizable compound and the like.

As a preferred example of the organic dispersion medium, alcohol-based solvents such as tarpineol, dihydroterpineol (mentanol), texanol, 3-methyl-3-methoxybutanol, and benzyl alcohol; glycol-based solvents such as ethylene glycol, propylene glycol, and diethylene glycol; Ether solvents such as dipropylene glycol methyl ether, methyl cellosolve (ethylene glycol monomethyl ether), cellosolve (ethylene glycol monoethyl ether), butyl carbitol (diethylene glycol monobutyl ether); diethylene glycol monobutyl ether acetate, dipropylene glycol methyl ether acetate, Ester solvents such as butyl glycol acetate, butyl diglycol acetate, butyl cellosolve acetate, butyl carbitol acetate (diethylene glycol monobutyl ether acetate), isobornyl acetate; hydrocarbon solvents such as toluene, xylene, naphtha, petroleum hydrocarbons, etc. Organic solvents such as; mineral spirit;

Among them, an organic solvent having a boiling point of 150 ° C. or higher, and further an organic solvent having a boiling point of 170 ° C. or higher are preferable from the viewpoint of improving the storage stability of the photosensitive composition and the handleability at the time of molding the conductive film. Further, as another preferable example, from the viewpoint of keeping the drying temperature after printing the conductive film low, an organic solvent having a boiling point of 250 ° C. or lower, and further an organic solvent having a boiling point of 220 ° C. or lower are preferable. As a result, productivity can be improved and production cost can be reduced.

Suitable commercially available organic solvents include, for example, Dowanol DPM ™ (boiling point: 190 ° C., manufactured by Dow Chemical Company), Dawanol DPMA ™ (boiling point: 209 ° C., manufactured by Dow Chemical Company), Mentanol. (Boiling point: 207 ° C.), Mentanol P (boiling point: 216 ° C.), Isopar H (boiling point: 176 ° C., manufactured by Kanto Fuel Co., Ltd.), SW-1800 (boiling point: 198 ° C., manufactured by Maruzen Oil Co., Ltd.) and the like. ..

When the photosensitive composition contains an organic dispersion medium, the proportion of the organic dispersion medium in the entire photosensitive composition is approximately 1 to 50% by mass, typically 3 to 3, although not particularly limited. It may be 30% by mass, for example 5 to 20% by mass.

<(G) Other additive components>
The photosensitive composition may further contain various additive components, if necessary, in addition to the above-mentioned components, as long as the effects of the techniques disclosed herein are not significantly impaired. As the additive component, one of the conventionally known components can be used alone, or two or more thereof can be used in combination as appropriate. Examples of additive components include inorganic fillers, photosensitizers, polymerization inhibitors, radical scavengers, antioxidants, UV absorbers, plasticizers, surfactants, leveling agents, thickeners, dispersants, etc. Examples thereof include antifoaming agents, antigelling agents, stabilizers, preservatives, pigments and the like. Although not particularly limited, the proportion of the additive component in the entire photosensitive composition is approximately 5% by mass or less, typically 3% by mass or less, for example, 2% by mass or less, preferably 1% by mass or less. It is good to do.

In the photosensitive composition disclosed herein, three kinds of organic components are properly balanced. That is, when the total of the cellulose-based organic binder, the (meth) acrylic-based photocurable resin, and the photopolymerizable compound is 100% by mass, the content ratio of the cellulose-based organic binder is 10 to 40% by mass. % (Preferably 20 to 35% by mass); (meth) acrylic photosetting resin content is 5 to 40% by mass (preferably 10 to 30% by mass); photopolymerizable compound content is 30 to 30 to 40% by mass. 60% by mass (preferably 50-60% by mass); As a result, the unexposed portion can be easily removed in the developing process, the developing time can be shortened, and the generation of residue can be reduced. In addition, it becomes easy to cure to the deep part of the exposed portion, the adhesion between the base material and the exposed portion can be improved, and the occurrence of peeling and disconnection can be suppressed. Therefore, a fine-line conductive layer having an L / S of 20 μm / 20 μm or less and an ultra-fine-line conductive layer having an L / S of 15 μm / 15 μm or less can be preferably formed. Further, a thick film-like conductive layer having a thickness of 5 μm or more and further 10 μm or more can be preferably formed. As a result, productivity and yield can be improved.

≪Application of photosensitive composition≫
According to the photosensitive composition disclosed herein, a fine-line conductive layer can be stably formed. Therefore, the photosensitive composition disclosed herein can be suitably used for forming a conductive layer in various electronic components such as an inductance component, a capacitor component, and a multilayer circuit board.

The electronic component may be of various mounting forms such as a surface mount type and a through-hole mount type. The electronic component may be a laminated type, a wound type, or a thin film type. Typical examples of inductance components include high-frequency filters, common-mode filters, inductors for high-frequency circuits (coils), inductors for general circuits (coils), high-frequency filters, choke coils, transformers, and the like.

An example of an electronic component is a ceramic electronic component. In the present specification, the "ceramic electronic component" refers to all electronic components made of a ceramic material, and is an amorphous ceramic base material (glass-ceramic base material) or a crystalline (that is, non-glass) ceramic. Includes all electronic components that have a substrate. Typical examples of ceramic electronic components are high-frequency filters with ceramic substrates, ceramic inductors (coils), ceramic capacitors, low temperature co-fired ceramics substrate (LTCC substrates), and high temperature co-fired laminated ceramic substrates. Materials (High Temperature Co-fired Ceramics Substrate: HTCC base material) and the like can be mentioned.

The ceramic material is not particularly limited, but for example, zirconium oxide (zirconia), magnesium oxide (magnesia), aluminum oxide (alumina), silicon oxide (silica), titanium oxide (titania), cerium oxide. Oxide-based materials such as (ceria), ittrium oxide (itria), barium titanate; composite oxide-based materials such as cordierite, mulite, forsterite, steatite, sialon, zircone, ferrite; silicon nitride (silicon knight) Rides), nitride-based materials such as aluminum nitride (aluminum nitride); carbide-based materials such as silicon carbide (silicon carbide); hydroxide-based materials such as hydroxyapatite; and the like.

FIG. 1 is a cross-sectional view schematically showing the structure of the laminated chip inductor 1. The dimensional relationship (length, width, thickness, etc.) in FIG. 1 does not necessarily reflect the actual dimensional relationship. Further, the reference numerals X and Y in the drawings represent the horizontal direction and the vertical direction, respectively. However, this is just for convenience of explanation.

The laminated chip inductor 1 includes a main body portion 10 and external electrodes 20 provided on both side surface portions of the main body portion 10 in the left-right direction X. The laminated chip inductor 1 has a size of, for example, 1608 shape (1.6 mm × 0.8 mm), 2520 shape (2.5 mm × 2.0 mm), or the like.

The main body 10 has a structure in which a ceramic layer (dielectric layer) 12 and an internal electrode layer 14 are integrated. The ceramic layer 12 is made of a ceramic material. In the vertical direction Y, the internal electrode layer 14 is arranged between the ceramic layers 12. The internal electrode layer 14 is formed by using the above-mentioned photosensitive composition. The internal electrode layers 14 adjacent to each other in the vertical direction Y with the ceramic layer 12 interposed therebetween are conducted through vias 16 provided in the ceramic layer 12. As a result, the internal electrode layer 14 is formed in a three-dimensional spiral shape (spiral shape). Both ends of the internal electrode layer 14 are connected to the external electrode 20.

Such a laminated chip inductor 1 can be manufactured, for example, by the following procedure.
That is, first, a paste containing a ceramic material as a raw material, a binder resin, and an organic solvent is prepared and supplied onto a carrier sheet to form a ceramic green sheet. Next, after rolling this ceramic green sheet, it is cut to a desired size to obtain a plurality of ceramic layer forming green sheets. Next, via holes are appropriately formed at predetermined positions of the plurality of ceramic layer forming green sheets by using a drilling machine or the like.

Next, using the above-mentioned photosensitive composition, a conductive film having a predetermined coil pattern is formed at a predetermined position on a plurality of green sheets for forming a ceramic layer. As an example, the following step: (Step S1: Molding step of film-like body) A conductive film composed of a dried body of the photosensitive composition by applying the photosensitive composition on a green sheet for forming a ceramic layer and drying the mixture. (Step S2: Exposure step) A step of covering the conductive film with a photomask having a predetermined opening pattern, exposing the conductive film through the photomask, and partially photocuring the conductive film; (Step S3: Development). Step) A conductive film in an unfired state can be formed by a manufacturing method including a step of etching a conductive film after photocuring to remove an unexposed portion.

In molding a conductive film using the above photosensitive composition, a conventionally known method can be appropriately used. For example, in (step S1), the photosensitive composition can be applied by using various printing methods such as screen printing, a bar coater, or the like. The photosensitive composition may be dried at a temperature below the boiling point of the photopolymerizable compound and the photopolymerization initiator, typically 50 to 100 ° C. In (step S2), for exposure, for example, an exposure machine that emits light in a wavelength range of 10 to 500 nm, for example, an ultraviolet irradiation lamp such as a high-pressure mercury lamp, a metal halide lamp, or a xenon lamp can be used. In (Step S3), an alkaline aqueous developer can typically be used for etching. For example, an aqueous solution containing sodium hydroxide, sodium carbonate or the like can be used. The concentration of the alkaline aqueous solution may be adjusted to, for example, 0.01 to 0.5% by mass.

Next, (step S4: firing step) a plurality of ceramic layer forming green sheets on which a conductive film in an unfired state is formed are laminated and pressure-bonded. As a result, a laminated body of unfired ceramic green sheets is produced. Next, the laminate of ceramic green sheets is fired at, for example, 600 to 1000 ° C. As a result, the ceramic green sheet is integrally sintered, and the main body 10 including the ceramic layer 12 and the internal electrode layer 14 made of the fired body of the photosensitive composition is formed. Then, an appropriate external electrode forming paste is applied to both ends of the main body portion 10 and fired to form the external electrode 20.
As described above, the multilayer chip inductor 1 can be manufactured.

Hereinafter, some examples of the present invention will be described, but the present invention is not intended to be limited to those shown in the examples.

(Preparation of photosensitive composition)
First, as a conductive powder, silver powder _{(D 50} particle size: 2 [mu] m) was prepared. Further, as an organic binder, a cellulosic polymer compound (resin acid value: 30 mgKOH / g, weight average molecular weight: 90,000, double bond equivalent: 0) was prepared. Moreover, urethane acrylate monomer was prepared as a photopolymerizable compound. Moreover, IRGACURE (trademark) 369 manufactured by BASF Japan Ltd. was prepared as a photopolymerization initiator. Further, as the photocurable resin, four types of acrylic resins a to d shown in Table 1 below were prepared. In addition, "ND" in the column of resin acid value in Table 1 indicates that it is below the lower limit of detection (not detected).

Then, the silver powder, the cellulosic polymer compound, the acrylic resins a to d, the photopolymerizable compound, the photopolymerization initiator, and other additive components (here, the photosensitizer and the antigelling agent) prepared above are used. A polymerization inhibitor and an ultraviolet absorber were used.) And were dissolved in an organic dispersion medium to prepare photosensitive compositions (Examples 1 to 8 and Comparative Examples 1 to 4). At this time, the cellulosic polymer compounds, the acrylic resins a to d, and the photopolymerizable compounds were blended so as to have the content ratios shown in Table 2. The mass ratio shown in Table 2 is the content ratio (mass%) of each component when the total of the cellulosic polymer compound, the acrylic resins a to d and the photopolymerizable compound is 100% by mass.

(Creation of wiring pattern)
First, the photosensitive compositions prepared above were coated on a commercially available ceramic green sheet in a size of □ 4 cm × 4 cm by screen printing. Next, this was dried at 60 ° C. for 15 minutes to form a conductive film (solid film) on the green sheet (film-like body forming step).
Next, a photomask was put on the conductive film. At this time, as the photomask, a photomask having a pattern in which the ratio (L / S) of the line width of the wiring to the interval portion (space) of the adjacent lines is 20 μm / 20 μm was used. In a state of covering the photomask on the conductive film, the exposure apparatus, the illumination 9 mJ / cm ^2, was irradiated with light under the conditions of exposure amount 1800 mJ / cm ^2, to cure the exposed portion (exposure step).
After the exposure, 0.1% by mass of an alkaline Na ₂ CO ₃ aqueous solution (developing solution) was sprayed onto the surface of the ceramic green sheet until a breakpoint (BP) was reached (development step). In addition, B. P. The time was set until the unexposed portion was developed with 0.1% by mass of an alkaline developer and it could be visually confirmed that the unexposed portion had disappeared.
After removing the unexposed portion in this way, it was washed with pure water and dried at room temperature. In this way, a conductive film (dry film) having a wiring pattern of L / S = 20 μm / 20 μm was formed on the ceramic green sheet.

(Evaluation of developability)
The developability of the wiring pattern produced above was evaluated.
That is, in the above-mentioned developing step, the time (development time) until reaching the breakpoint (BP) was measured. The results are shown in the "Development time (seconds)" column of Table 2. In addition, based on this result, the developability was evaluated by the following indexes. The results are shown in the column of "evaluation of developability" in Table 2.
"◎": Development time is within 45 seconds (developability is particularly good).
"○": Development time is within 60 seconds (good developability).
"X": Development time is longer than 60 seconds (developability is poor).

(Evaluation of resolution)
In the above exposure step, a photomask having a pattern of L / S of 15 μm / 15 μm, 20 μm / 20 μm, 25 μm / 25 μm, 30 μm / 30 μm, and 40 μm / 40 μm was used. Further, in the development step, the development time was set to 1.4 times the breakpoint (BP) in consideration of the development margin. Other than that, a conductive film (dry film) of the wiring pattern having a predetermined L / S was formed in the same manner as the formation of the wiring pattern.

Next, a total of 10 fields of view were observed with an optical microscope for each of the prepared wiring patterns, and the presence or absence of peeling and residues was confirmed from the obtained observation images. As an example, FIG. 2 shows an optical microscope image of the wiring pattern of Example 1. Then, the smallest L / S in which no peeling or residue was confirmed was defined as the resolution. The results are shown in the "Resolution (μm)" column of Table 2. In addition, based on this result, the resolution was evaluated using the following indexes. The results are shown in the column of "Evaluation of resolution" in Table 2.
"⊚": The resolution (L / S) is 15 μm / 15 μm.
"○": The resolution (L / S) is 20 μm / 20 μm.
"X": The resolution (L / S) is 25 μm / 25 μm or more.

(Comprehensive evaluation)
Based on the evaluation of developability and resolution, a comprehensive evaluation was performed using the following indexes. The results are shown in the "Comprehensive Evaluation" column of Table 2.
"◎": Both developability and resolution are ◎.
"○": One of the developability and the resolvability is ○, and one is ⊚ or ○.
"X": At least one of developability and resolution is x.

Comparative Example 1 is a test example that does not contain an acrylic resin. As shown in Table 2, in Comparative Example 1, although the developing time was overwhelmingly short, peeling occurred when the L / S was 25 μm / 25 μm or less, and the resolution was insufficient. Further, Comparative Example 3 is a test example in which the proportion of the photopolymerizable compound is higher than that of Comparative Example 1. As shown in Table 2, in Comparative Example 3, although the developing time was short, peeling occurred when the L / S was 25 μm / 25 μm or less, and the resolution was still insufficient.

Further, Comparative Example 2 is a test example containing no cellulosic polymer compound. As shown in Table 2, in Comparative Example 2, when the developing time was long and the L / S was 20 μm / 20 μm or less, a residue was confirmed, and the resolution was insufficient. Further, Comparative Example 4 is a test example using an acrylic resin d having no acid value (acid-free) as the acrylic resin. As shown in Table 2, in Comparative Example 4, the developing time was longer than that in Comparative Example 2.

When the total of the cellulosic polymer compounds, the acrylic resins a to c having an acid value, and the photopolymerizable compounds is 100% by mass with respect to these Comparative Examples 1 to 4, the cellulosic polymer compounds In Examples 1 to 8 containing 10 to 40% by mass of acrylic resins a to 40 having an acid value, 5 to 40% by mass of acrylic resins a to c, and 30 to 60% by mass of a photopolymerizable compound, a cellulosic polymer compound was contained. The development time was relatively short as compared with Comparative Example 2 without Comparative Example 2 and Comparative Example 4 using the acid-free acrylate d, and the development could be completed within 60 seconds. Further, in Examples 1 to 8, peeling and generation of residue were suppressed, and a fine line having an L / S of 20 μm / 20 μm or less could be suitably formed.

Among them, when the total of the cellulosic polymer compound, the acrylic resins a to c having an acid value and the photopolymerizable compound is 100% by mass, the cellulosic polymer compound is 20 to 35% by mass. Examples 2, 3, 7, and 8 containing 10 to 30% by mass of acrylic resins a to c having an acid value and 50 to 60% by mass of a photopolymerizable compound are particularly excellent in developability and resolution. Was there. That is, the development time was suppressed to 45 seconds or less, and the development time was significantly shortened. Further, an ultrafine line having an L / S of 15 μm / 15 μm could also be suitably formed.
These results show the significance of the technology disclosed herein.

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 the gist thereof.

1 Multilayer chip inductor 10 Main body 12 Ceramic layer 14 Internal electrode layer 20 External electrode

Claims (9)

With conductive powder
Cellulose-based organic binder and
A (meth) acrylic photocurable resin with an acid value,
With photopolymerizable compounds
Including a photopolymerization initiator,
When the total of the cellulosic organic binder, the (meth) acrylic photocurable resin having an acid value, and the photopolymerizable compound is 100% by mass,
The content ratio of the cellulosic organic binder is 10 to 40% by mass;
The content ratio of the (meth) acrylic photocurable resin having an acid value is 5 to 40% by mass;
The content ratio of the photopolymerizable compound is 30 to 60% by mass;
The photosensitive composition. The cellulosic organic binder has an acid value of 20 mgKOH / g or more.
The photosensitive composition according to claim 1. The acid value of the (meth) acrylic photocurable resin having an acid value is 50 mgKOH / g or more and 150 mgKOH / g or less.
The photosensitive composition according to claim 1 or 2. The weight average molecular weight of the (meth) acrylic photocurable resin having an acid value is 10,000 or more and 30,000 or less.
The photosensitive composition according to any one of claims 1 to 3. When the total of the cellulosic organic binder, the (meth) acrylic photocurable resin having an acid value, and the photopolymerizable compound is 100% by mass,
The content ratio of the cellulosic organic binder is 20 to 35% by mass;
The content ratio of the (meth) acrylic photocurable resin having an acid value is 10 to 30% by mass;
The content ratio of the photopolymerizable compound is 50 to 60% by mass;
Is,
The photosensitive composition according to any one of claims 1 to 4. The conductive powder contains silver-based particles.
The photosensitive composition according to any one of claims 1 to 5. With the green sheet
A conductive film arranged on the green sheet and made of a dried product of the photosensitive composition according to any one of claims 1 to 6.
A complex that comprises. An electronic component comprising a conductive layer made of a fired body of the photosensitive composition according to any one of claims 1 to 6. The photosensitive composition according to any one of claims 1 to 6 is applied onto a substrate, exposed and developed, and then fired to form a conductive layer made of a fired body of the photosensitive composition. A method of manufacturing an electronic component, including the process of performing.