Photo-hardening conductive composition

Abstract

The invention relates to a photo-hardening conductive composition, which comprises a photo-curing component, a conductive material and a flatting agent. The photocuring component comprises a reactive monomer with an acid ester group, an adhesive and a photoinitiator. And the weight ratio of the adhesive to the reactive monomer with the acid ester group is more than 4. By matching the components of the photo-hardening conductive composition and designing the weight ratio of the adhesive to the reactive monomer with the acid ester group, the conductive hardened material formed by the photo-hardening conductive composition has the advantage of thermal dimensional stability, so that the thermal dimensional stability of the conductive hardened material is improved in the co-sintering process of manufacturing a passive electronic component. The problem of low yield or poor conductivity caused by large size change can be reduced.

Description

Technical Field

[0001] The present invention relates to a conductive composition, and in particular to a photocurable conductive composition. Background Art

[0002] With the booming development of information and communication technology, artificial intelligence and electric vehicles, the demand for passive electronic components such as inductors, resistors, capacitors or transformers is increasing, and these passive electronic components are one of the key links for the booming development of these fields. At present, most of these passive electronic components are mainly formed by multilayer ceramic component process technology.

[0003] The laminated ceramic component manufacturing process technology includes applying a photohardening conductive paste on a ceramic green substrate by screen printing, and performing a light treatment to form a photohardening patterned circuit layer, and then performing a co-sintering treatment under the condition of 800° C. to 900° C. to form a conductive circuit layer on the ceramic green substrate. During the co-sintering process, the photohardening patterned circuit layer and the ceramic green substrate each have their own thermal shrinkage rate, and the ceramic green substrate is often relatively fragile at a temperature of 300° C. to 450° C. due to the existence of unfavorable factors such as the resin in the ceramic green substrate may be cracked. In this case, the size of the photohardening patterned circuit layer changes greatly, which will cause the ceramic green substrate to crack. Therefore, the thermal matching between the photohardening patterned circuit layer and the ceramic green substrate becomes one of the important considerations to avoid the size of the photohardening patterned circuit layer changing greatly due to heat, resulting in cracks or delamination of the laminated ceramic component or deformation of the conductive circuit, thereby reducing the yield or electrical performance of the laminated ceramic component. To solve the above problems, most methods adopt the method of controlling the temperature rise conditions of the co-sintering process. However, this method will increase the process time. Summary of the invention

[0004] An object of the present invention is to provide a photocurable conductive composition that can be used to form a conductive cured product having thermal dimensional stability.

[0005] The photocurable conductive composition of the present invention comprises a photocurable component, a conductive material and a leveling agent. The photocurable component comprises a reactive monomer having an acid ester group, a binder and a photoinitiator. The weight ratio of the binder to the reactive monomer having an acid ester group is greater than 4.

[0006] In the light-curable conductive composition of the present invention, the weight ratio of the binder to the reactive monomer having an acid ester group is in a range of 4 to 28.

[0007] In the light-curable conductive composition of the present invention, the weight ratio of the binder to the reactive monomer having an acid ester group is in a range of 4 to 14.

[0008] In the light-curable conductive composition of the present invention, the binder is selected from acrylate copolymer, phenolic epoxy acrylate resin, methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, or any combination thereof.

[0009] In the photocurable conductive composition of the present invention, the acid ester group of the reactive monomer having an acid ester group is an acrylate group or a methacrylate group.

[0010] In the photocurable conductive composition of the present invention, the reactive monomer having an acid ester group is selected from dipentaerythritol hexaacrylate, decaethoxylated bisphenol A dimethacrylate, tetraethoxylated bisphenol A diacrylate, tetraethoxylated bisphenol A dimethacrylate, tetraethylene glycol diacrylate, or any combination thereof.

[0011] The light-curable conductive composition of the present invention, the leveling agent is selected from fluorine-based leveling agents, polyoxyethylene ether leveling agents, sulfonate leveling agents, siloxane leveling agents, or any combination thereof.

[0012] The photocurable conductive composition of the present invention has a conductive material which is a metal material.

[0013] The photocurable conductive composition of the present invention comprises a metal material selected from silver, gold, nickel, aluminum, copper, platinum, palladium, rhodium, osmium, or any combination thereof.

[0014] The beneficial effect of the present invention is that through the combination of the ingredients of the photocurable conductive composition and the design of the weight ratio of the binder to the reactive monomer having an acid ester group, the conductive cured product formed by the photocurable conductive composition of the present invention has the advantage of thermal dimensional stability, so that in the co-sintering process of manufacturing passive electronic components, the problem of low yield or poor conductivity caused by large dimensional changes can be reduced. DETAILED DESCRIPTION

[0015] The present invention will be described in detail below.

[0016] <Photocurable conductive composition>

[0017] The photocurable conductive composition comprises a photocurable component, a conductive material and a leveling agent. The photocurable component comprises a reactive monomer having an acid ester group, a binder and a photoinitiator. The weight ratio of the binder to the reactive monomer having an acid ester group is greater than 4.

[0018] [Photocuring component]

[0019] In some embodiments of the present invention, the acid ester group of the reactive monomer having an acid ester group is an acrylate group or a methacrylate group. In some embodiments of the present invention, the reactive monomer having an acid ester group further has a plurality of ethoxy groups.

[0020] The reactive monomer having an acid ester group can be used alone or in combination, and the reactive monomer having an acid ester group is, for example but not limited to, dipentaerythritol hexaacrylate, decaethoxylated bisphenol A dimethacrylate, tetraethoxylated bisphenol A diacrylate, tetraethoxylated bisphenol A dimethacrylate, or tetraethylene glycol diacrylate, etc. In some embodiments of the present invention, the reactive monomer having an acid ester group is selected from dipentaerythritol hexaacrylate, decaethoxylated bisphenol A dimethacrylate, tetraethoxylated bisphenol A diacrylate, tetraethoxylated bisphenol A dimethacrylate, tetraethylene glycol diacrylate, or any combination thereof.

[0021] The binder can be used alone or in combination, and the binder is, for example, but not limited to, acrylate copolymer, phenolic epoxy acrylate resin, methyl cellulose, ethyl cellulose, or hydroxymethyl cellulose. In some embodiments of the present invention, the binder is selected from acrylate copolymer, phenolic epoxy acrylate resin, methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, or any combination thereof. In some embodiments of the present invention, the weight ratio of the binder to the reactive monomer having an acid ester group is in the range of 4 to 28. In some embodiments of the present invention, the weight ratio of the binder to the reactive monomer having an acid ester group is in the range of 4 to 14.

[0022] The photoinitiator can be used alone or in combination, and the photoinitiator is, for example but not limited to, a carbazole oxime ester photoinitiator, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl 2,4,6-trimethylformylphenylphosphinate (TPO-L), acetophenone dimethyl ketal, benzophenone, 2,4-dimethylthioxanthone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, (2,6-dimethoxybenzoyl)-2,4,4-pentylphosphine oxide, or 2,4,6-trimethylbenzoyldiphenylphosphine oxide. In some embodiments of the present invention, the photoinitiator is selected from phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl 2,4,6-trimethylformylphenylphosphonate, acetophenone dimethyl ketal, benzophenone, 2,4-dimethylthioxanthone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, (2,6-dimethoxybenzoyl)-2,4,4-pentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, carbazole oxime ester photoinitiator, or any combination thereof.

[0023] [Conductive materials]

[0024] The shape of the conductive material is not particularly limited, for example, it is in powder form. In some embodiments of the present invention, the conductive material is a metal material. The metal material can be used alone or in combination, and the metal material is, for example, but not limited to, silver, gold, nickel, aluminum, copper, platinum, palladium, rhodium, or osmium. In some embodiments of the present invention, the metal material is selected from silver, gold, nickel, aluminum, copper, platinum, palladium, rhodium, osmium, or any combination thereof. In some embodiments of the present invention, the total amount of the conductive material is 70wt% to 81wt%, based on the total amount of the photohardenable conductive composition being 100wt%. In some embodiments of the present invention, the total amount of the conductive material is 75wt% to 81wt%, based on the total amount of the photohardenable conductive composition being 100wt%.

[0025] [Leveling agent]

[0026] The leveling agent can be used alone or in combination, and the leveling agent is, for example, but not limited to, a fluorine-based leveling agent, a polyoxyethylene ether leveling agent, a sulfonate leveling agent, or a siloxane leveling agent. The fluorine-based leveling agent can be used alone or in combination, and the fluorine-based leveling agent is, for example, but not limited to, a leveling agent containing polytetrafluoroethylene and polyoxyethylene. In some embodiments of the present invention, the leveling agent is selected from a fluorine-based leveling agent, a polyoxyethylene ether leveling agent, a sulfonate leveling agent, a siloxane leveling agent, or any combination thereof. In some embodiments of the present invention, based on the total amount of the photocurable conductive composition being 100wt%, the total amount of the leveling agent is greater than 0wt% and less than 0.6wt%. In some embodiments of the present invention, based on the total amount of the photocurable conductive composition being 100wt%, the total amount of the leveling agent is 0.4wt% to 0.6wt%.

[0027] In some embodiments of the present invention, the photocurable conductive composition further includes a solvent.

[0028] [Solvent]

[0029] The solvent can be used alone or in combination, and the solvent may be, for example but not limited to, propylene glycol methyl ether acetate (2-Acetoxy-1-methoxypropane, PGMEA for short), diethylene glycol monohexyl ether, dipropylene glycol butyl ether, 2-(2-hydroxypropoxy)-1-propanol, or 1-[1-methyl-2-(2-propenyloxy)ethoxy]-2-propanol, etc.

[0030] The photocurable conductive composition of the present invention can be used in passive electronic components such as capacitors or inductors, and as a material for forming internal electrodes in these passive electronic components. The conductive hardened material formed by the photocurable conductive composition of the present invention can be used as an internal electrode of a ceramic passive electronic component.

[0031] The present invention will be further described with reference to the following examples, but it should be understood that the examples are only for illustration and should not be construed as limitations on the implementation of the present invention.

[0032] Example 1 Photocurable conductive composition

[0033] 15.6 grams of silver powder, 2.8 grams of acrylate copolymer (ingredients: formed by polymerization of methyl methacrylate, methyl acrylate and styrene), 0.6 grams of dipentaerythritol hexaacrylate, 0.2 grams of photoinitiator (ingredients: carbazole oxime ester series), 0.1 grams of leveling agent (ingredients: fluorine series), and 0.6 grams of PGMEA are mixed evenly to form a photocurable conductive composition.

[0034] Examples 2 to 4 and Comparative Examples 1 to 6

[0035] The preparation steps of Examples 2 to 4 and Comparative Examples 1 to 6 are substantially the same as those of Example 1, and the main difference is that the type of reactive monomer having an acid ester group or the weight ratio of the binder to the reactive monomer having an acid ester group is changed.

[0036] [Evaluation items]

[0037] Measurement of thermal dimensional stability: The photocurable compositions of Examples 1 to 4 and Comparative Examples 1 to 6 are applied into a coating with a thickness of 0.3 mm, and then placed in an oven set at a temperature of 120°C for a baking treatment for 6 hours. Then, the coating is taken out of the oven and irradiated with light having a wavelength of 365 nm for 10 minutes to perform a photocuring reaction to obtain a conductive cured film. The conductive cured film is cut into test pieces with a size of 0.3 cm x 0.3 cm. Each test piece is placed in a thermal mechanical analyzer (brand: TA; model: Q-400), and then heated to 900°C at a heating rate of 10°C / min. Then, the built-in software in the thermal mechanical analyzer is used to calculate the dimensional change rate of the test piece when the temperature is 395±15°C.

[0038] Table 1

[0039]

[0040]

[0041] From the experimental results of Examples 1 to 4 in Table 1, it can be seen that when the weight ratio of the binder of the photocurable conductive composition to the reactive monomer having an acid ester group is controlled to be greater than 4, the dimensional change rate of the conductive cured product formed by the photocurable conductive composition is less than 20%. In contrast, in Comparative Examples 1 to 6, when the weight ratio of the binder of the photocurable conductive composition to the reactive monomer having an acid ester group is controlled to be 3.18, 3.4 or 3.4, the dimensional change rate of the conductive cured product formed by the photocurable conductive composition is greater than 25%.

[0042] In summary, through the combination of the ingredients of the photocurable conductive composition and the design of the weight ratio of the binder to the reactive monomer having an acid ester group, the conductive cured product formed by the photocurable conductive composition of the present invention has the advantage of thermal dimensional stability, so that in the co-sintering process of manufacturing passive electronic components, the problem of low yield or poor conductivity caused by large dimensional changes can be reduced, so the purpose of the present invention can be achieved.

[0043] However, the above is only an embodiment of the present invention and should not be used to limit the scope of the present invention. All simple equivalent changes and modifications made according to the claims and the patent specification of the present invention are still within the scope of the present invention.

Claims

1. A photocurable conductive composition, characterized in that: The photocurable conductive composition comprises: A photocurable component, a conductive material and a leveling agent, wherein the photocurable component comprises a reactive monomer having an acid ester group, a binder and a photoinitiator, and the weight ratio of the binder to the reactive monomer having an acid ester group is greater than 4.

2. The photocurable conductive composition according to claim 1, wherein: The weight ratio of the binder to the reactive monomer having an acid ester group is in a range of 4 to 28.

3. The photocurable conductive composition according to claim 2, wherein: The weight ratio of the binder to the reactive monomer having an acid ester group is in the range of 4 to 14.

4. The photocurable conductive composition according to claim 1, wherein: The binder is selected from acrylate copolymer, phenolic epoxy acrylate resin, methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, or any combination thereof.

5. The photocurable conductive composition according to claim 1, wherein: The acid ester group of the reactive monomer having an acid ester group is an acrylate group or a methacrylate group.

6. The photocurable conductive composition according to claim 1, wherein: The reactive monomer having an acid ester group is selected from dipentaerythritol hexaacrylate, decaethoxylated bisphenol A dimethacrylate, tetraethoxylated bisphenol A diacrylate, tetraethoxylated bisphenol A dimethacrylate, tetraethylene glycol diacrylate, or any combination thereof.

7. The photocurable conductive composition according to claim 1, wherein: The leveling agent is selected from fluorine-based leveling agents, polyoxyethylene ether leveling agents, sulfonate leveling agents, siloxane leveling agents, or any combination thereof.

8. The photocurable conductive composition according to claim 1, wherein: The conductive material is a metal material.

9. The photocurable conductive composition according to claim 8, wherein: The metal material is selected from silver, gold, nickel, aluminum, copper, platinum, palladium, rhodium, osmium, or any combination thereof.

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