阅读说明：本技术 一种水性mlcc专用辊印镍浆及其制备方法 (Roll printing nickel slurry special for water-based MLCC and preparation method thereof ) 是由 何伟雄 黄大凯 于 2021-04-28 设计创作，主要内容包括：本发明公开一种水性MLCC专用辊印镍浆,所述专用辊印镍浆包括以下重量份原料：水溶性粘合剂5～18份,镍分散液60～90份,无机填料分散液1～15份,助剂1～5份,固化剂1～15份；所述水溶性粘合剂为水溶性树脂与纯净水2:90 98配制；所述镍分散液为镍粉与纯净水80:15 20配制；所述无机填料分散液为无机填料与纯净水74:20 30配制,本发明相比传统MLCC镍浆VOCs含量大幅下降,其他性能与传统镍浆制备的MLCC性能相当,本发明制得的镍浆,提升MLCC的电容值。(The invention discloses a special roll printing nickel paste for a water-based MLCC (multilayer ceramic capacitor), which comprises the following raw materials in parts by weight: 5-18 parts of water-soluble adhesive, 60-90 parts of nickel dispersion liquid, 1-15 parts of inorganic filler dispersion liquid, 1-5 parts of auxiliary agent and 1-15 parts of curing agent; the water-soluble adhesive is prepared by water-soluble resin and purified water 2: 9098; the nickel dispersion liquid is prepared by nickel powder and purified water 80: 1520; the inorganic filler dispersion liquid is prepared from inorganic filler and purified water 74: 2030, compared with the traditional MLCC nickel paste, the content of VOCs in the MLCC nickel paste is greatly reduced, and other properties are equivalent to those of the MLCC prepared from the traditional nickel paste.)

1. The special roll printing nickel paste for the water-based MLCC is characterized by comprising the following raw materials in parts by weight: 5-18 parts of water-soluble adhesive, 60-90 parts of nickel dispersion liquid, 1-15 parts of inorganic filler dispersion liquid, 1-5 parts of auxiliary agent and 1-15 parts of curing agent.

2. The aqueous MLCC roll printing nickel paste special for the roll printing according to claim 1,

the water-soluble adhesive is prepared by water-soluble resin and purified water 2: 9098;

the nickel dispersion liquid is prepared by nickel powder and purified water 80: 1520;

the inorganic filler dispersion is prepared by mixing inorganic filler and purified water 74: 2030.

3. The roll printing nickel paste special for the aqueous MLCC according to claim 2, wherein the water-soluble resin is one or more of hydroxyethyl cellulose, hydroxypropyl cellulose and hydroxypropyl methyl cellulose.

4. The special roll-printing nickel slurry for the waterborne MLCC according to claim 2, wherein the nickel powder is spherical nickel powder, the particle size D50 of the nickel powder is 20-60nm, and the maximum particle size of the nickel powder is 60-90 nm.

5. The roll printing nickel paste special for the aqueous MLCC according to claim 2, wherein the inorganic filler is one or more of nano barium titanate, nano magnesium oxide and nano yttrium oxide.

6. The roll printing nickel paste special for the aqueous MLCC according to claim 5, wherein the inorganic filler D50 is 20-60nm, and the maximum particle size is 60-90 nm.

7. The aqueous MLCC roll printing nickel paste special for the roll printing nickel paste according to claim 1, wherein the curing agent is aqueous blocked isocyanate.

8. The aqueous MLCC roll printing nickel paste special for the roll printing of the claim 1, wherein the auxiliary agent is an aqueous auxiliary agent; the auxiliary agent is one or more of a dispersing agent, a defoaming agent and a flatting agent.

9. The preparation method of the roll printing nickel slurry special for the aqueous MLCC, which is characterized by comprising the following steps of:

s1, uniformly mixing the water-soluble resin and purified water to obtain a water-soluble adhesive;

s2, uniformly stirring the nickel powder, the purified water and the auxiliary agent, and grinding to obtain a nickel dispersion liquid;

s3, stirring and uniformly dispersing the inorganic filler, purified water and the auxiliary agent to obtain an inorganic filler dispersion liquid;

s4, adding the curing agent and the auxiliary agent into the materials obtained from S1, S2 and S3, stirring and dispersing uniformly;

and S5, filtering the slurry of the S4 system with a 750850-mesh sieve, and performing centrifugal defoaming to obtain the finished product nickel slurry.

10. The preparation method according to claim 9, comprising the following specific steps:

s1, mixing water-soluble resin and purified water, heating to 3550 ℃, stirring for 30min in a high-speed shearing dispersion machine with the rotation speed of 8001400rpm, and uniformly obtaining a water-soluble binder;

s2, stirring the nickel powder, the purified water and the auxiliary agent in a high-speed shearing dispersion machine with the rotation speed of 10001400rpm for 5min, uniformly stirring, and then transferring to a 25003200rpm nano sand mill for grinding for 15min to obtain a nickel dispersion liquid;

s3, stirring the inorganic filler, purified water and the auxiliary agent in a high-speed shearing dispersion machine with the rotation speed of 10001400rpm for 5min, uniformly stirring, transferring to a micro-jet flow ultrahigh-pressure homogenizer, and grinding for 15min at the pressure of 2003000MPa to obtain an inorganic filler dispersion liquid;

s4, adding the curing agent and the auxiliary agent into the materials obtained in S1, S2 and S3, stirring for 15min in a high-speed shearing dispersion machine with the rotating speed of 10001400rpm, uniformly transferring the materials to a high-pressure homogenizer, and dispersing for 60min at the pressure of 80150 MPa;

and S5, filtering the slurry by using a 800-mesh filter screen, and performing centrifugal defoaming to obtain the finished product nickel slurry.

Technical Field

The invention relates to roll printing conductive nickel paste for MLCC, in particular to special roll printing nickel paste for water MLCC and a preparation method thereof.

Background

The chip multilayer ceramic capacitor (MLCC) has larger range of applied voltage and capacitance value, has the advantages of stable work, wide range, small dielectric loss, small volume, low price and the like, is widely applied to the fields of consumer electronics, industry, communication, automobiles, military industry and the like, and is one of the chip components with the largest current yield and the fastest development.

The ceramic capacitor is slightly influenced by temperature, has long service life and is miniaturized, the market proportion of the whole capacitor reaches 60 percent, and the MLCC accounts for 90 percent of the ceramic capacitor; the MLCC sales volume in China rises year by year, the MLCC sales volume in 2018 reaches 3 trillions, and the MLCC sales volume is predicted to reach 3.7 trillions in 2022; the conductive nickel paste applied by MLCC manufacturers is various and is mainly used for printing inner electrodes of the MLCC; with the increase of the MLCC yield, the demand of nickel slurry is also greatly increased.

The MLCC conductive nickel paste which is mainly used in the market at present is a paste containing an organic solvent, particularly roll printing nickel paste, the viscosity is very low, the organic solvent accounts for 15-50% of the formula of the paste, and the volatilization of the organic solvent in the paste has the disadvantages of great harm to human bodies, great influence on ecological environment and prohibition or reduction of the use of the organic solvent required by environmental protection departments.

Disclosure of Invention

The invention aims to provide a special roll printing nickel paste for an aqueous MLCC and a preparation method thereof, and aims to solve the problems that the roll printing nickel paste for the MLCC in the prior art contains an organic solvent and has high content of volatile organic compounds.

The invention provides a special roll printing nickel paste for a water-based MLCC (multilayer ceramic capacitor), which comprises the following raw materials in parts by weight: 5-18 parts of water-soluble adhesive, 60-90 parts of nickel dispersion liquid, 1-15 parts of inorganic filler dispersion liquid, 1-5 parts of auxiliary agent and 1-15 parts of curing agent.

Further, the water-soluble adhesive is prepared by mixing water-soluble resin and purified water 2: 9098;

the nickel dispersion liquid is prepared by nickel powder and purified water 80: 1520;

the inorganic filler dispersion is prepared by mixing inorganic filler and purified water 74: 2030.

Further, the water-soluble resin is one or more of hydroxyethyl cellulose, hydroxypropyl cellulose and hydroxypropyl methyl cellulose.

Further, the nickel powder is spherical nickel powder, the particle size D50 of the nickel powder is 20-60nm, and the maximum particle size of the nickel powder is 60-90 nm.

Further, the inorganic filler is one or more of nano barium titanate, nano magnesium oxide and nano yttrium oxide.

Further, the inorganic filler D50 is 20-60nm, and the maximum particle size is 60-90 nm.

Further, the curing agent is water-based blocked isocyanate.

Further, the auxiliary agent is an aqueous auxiliary agent; the auxiliary agent is one or more of a dispersing agent, a defoaming agent and a flatting agent.

A preparation method of roll printing nickel slurry special for water-based MLCC comprises the following steps:

s1, uniformly mixing the water-soluble resin and purified water to obtain a water-soluble adhesive;

s2, uniformly stirring the nickel powder, the purified water and the auxiliary agent, and grinding to obtain a nickel dispersion liquid;

s3, stirring and uniformly dispersing the inorganic filler, purified water and the auxiliary agent to obtain an inorganic filler dispersion liquid;

s4, adding the curing agent and the auxiliary agent into the materials obtained from S1, S2 and S3, stirring and dispersing uniformly;

and S5, filtering the slurry of the S4 system with a 750850-mesh sieve, and performing centrifugal defoaming to obtain the finished product nickel slurry.

Further, the preparation method comprises the following specific steps:

s1, mixing water-soluble resin and purified water, heating to 3550 ℃, stirring for 30min in a high-speed shearing dispersion machine with the rotation speed of 8001400rpm, and uniformly obtaining a water-soluble binder;

s2, stirring the nickel powder, the purified water and the auxiliary agent in a high-speed shearing dispersion machine with the rotation speed of 10001400rpm for 5min, uniformly stirring, and then transferring to a 25003200rpm nano sand mill for grinding for 15min to obtain a nickel dispersion liquid;

s3, stirring the inorganic filler, purified water and the auxiliary agent in a high-speed shearing dispersion machine with the rotation speed of 10001400rpm for 5min, uniformly stirring, transferring to a micro-jet flow ultrahigh-pressure homogenizer, and grinding for 15min at the pressure of 2003000MPa to obtain an inorganic filler dispersion liquid;

s4, adding the curing agent and the auxiliary agent into the materials obtained in S1, S2 and S3, stirring for 15min in a high-speed shearing dispersion machine with the rotating speed of 10001400rpm, uniformly transferring the materials to a high-pressure homogenizer, and dispersing for 60min at the pressure of 80150 MPa;

and S5, filtering the slurry by using a 800-mesh filter screen, and performing centrifugal defoaming to obtain the finished product nickel slurry.

The roll printing nickel slurry special for the water-based MLCC is prepared from hydroxyethyl cellulose, hydroxypropyl methylcellulose, hydroxypropyl cellulose and hydrophilic organic polymers, and has the film forming performance equivalent to that of roll printing nickel slurry of an organic solvent after being dried.

Detailed Description

Technical solutions in embodiments of the present invention are clearly and completely described in order to enable those skilled in the art to better understand the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terms first, second and the like in the description and in the claims of the present invention are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

Example 1 a method for preparing a roll printing nickel paste for an aqueous MLCC, comprising the steps of:

s1, mixing 1 part of hydroxyethyl cellulose, 0.5 part of hydroxypropyl cellulose and 0.5 part of hydroxypropyl methyl cellulose with 98 parts of purified water, heating to 45 ℃, and uniformly stirring in a high-speed shearing dispersion machine at the rotating speed of 1200rpm for 30min to obtain a water-soluble resin binder with the solid content of 2%;

s2, stirring 80.5 parts of nickel powder, 18.5 parts of purified water and 1 part of auxiliary agent uniformly in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, and then transferring to a nano sand mill with the rotation speed of 3000rpm for grinding for 15min to obtain nano nickel dispersion liquid;

s3, stirring 70 parts of nano barium titanate, 2 parts of nano magnesium oxide, 2 parts of nano yttrium oxide, 25 parts of purified water and 1 part of dispersing agent in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, uniformly stirring, transferring to a micro-jet ultrahigh-pressure homogenizer, and grinding for 15min at the pressure of 250MPa to obtain a nano inorganic filler dispersion liquid;

s4, adding 2 parts of water-based closed isocyanate curing agent, 0.5 part of defoaming auxiliary agent and 0.5 part of flatting agent into 9 parts of the material obtained in S1, 80 parts of the material obtained in S2 and 8 parts of the material obtained in S3, stirring for 15min in a high-speed shearing dispersion machine with the rotating speed of 1200rpm, uniformly moving the mixture into a high-pressure homogenizer, and dispersing for 60min under the pressure of 100 MPa;

and S5, filtering the S4 slurry with 800 meshes, and performing centrifugal defoaming to obtain a finished nickel slurry product.

Embodiment 2, a method for preparing roll printing nickel paste special for aqueous MLCC, comprising the following steps:

s1, mixing 1 part of hydroxyethyl cellulose, 0.5 part of hydroxypropyl cellulose and 0.5 part of hydroxypropyl methyl cellulose with 98 parts of purified water, heating to 45 ℃, and uniformly stirring in a high-speed shearing dispersion machine at the rotating speed of 1200rpm for 30min to obtain a water-soluble resin binder with the solid content of 2%;

s2, stirring 82.5 parts of nickel powder, 16.5 parts of purified water and 1 part of auxiliary agent uniformly in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, and then transferring to a nano sand mill with the rotation speed of 3000rpm for grinding for 15min to obtain nano nickel dispersion liquid;

s3, stirring 70 parts of nano barium titanate, 2 parts of nano magnesium oxide, 2 parts of nano yttrium oxide, 25 parts of purified water and 1 part of dispersing agent in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, uniformly stirring, transferring to a micro-jet ultrahigh-pressure homogenizer, and grinding for 15min at the pressure of 250MPa to obtain a nano inorganic filler dispersion liquid;

s4, adding 2 parts of water-based closed isocyanate curing agent, 0.5 part of defoaming auxiliary agent and 0.5 part of flatting agent into 9 parts of the material obtained in S1, 80 parts of the material obtained in S2 and 8 parts of the material obtained in S3, stirring for 15min in a high-speed shearing dispersion machine with the rotating speed of 1200rpm, uniformly moving the mixture into a high-pressure homogenizer, and dispersing for 60min under the pressure of 100 MPa;

and S5, filtering the S4 slurry with 800 meshes, and performing centrifugal defoaming to obtain a finished nickel slurry product.

Example 3 a method for preparing a roll printing nickel paste for an aqueous MLCC, comprising the steps of:

s1, mixing 1 part of hydroxyethyl cellulose, 0.5 part of hydroxypropyl cellulose and 0.5 part of hydroxypropyl methyl cellulose with 98 parts of purified water, heating to 45 ℃, and uniformly stirring in a high-speed shearing dispersion machine at the rotating speed of 1200rpm for 30min to obtain a water-soluble resin binder with the solid content of 2%;

s2, stirring 84.5 parts of nickel powder, 14.5 parts of purified water and 1 part of auxiliary agent uniformly in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, and then transferring to a nano sand mill with the rotation speed of 3000rpm for grinding for 15min to obtain nano nickel dispersion liquid;

s3, stirring 70 parts of nano barium titanate, 2 parts of nano magnesium oxide, 2 parts of nano yttrium oxide, 25 parts of purified water and 1 part of dispersing agent in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, uniformly stirring, transferring to a micro-jet ultrahigh-pressure homogenizer, and grinding for 15min at the pressure of 250MPa to obtain a nano inorganic filler dispersion liquid;

s4, adding 2 parts of water-based closed isocyanate curing agent, 0.5 part of defoaming auxiliary agent and 0.5 part of flatting agent into 9 parts of the material obtained in S1, 80 parts of the material obtained in S2 and 8 parts of the material obtained in S3, stirring for 15min in a high-speed shearing dispersion machine with the rotating speed of 1200rpm, uniformly moving the mixture into a high-pressure homogenizer, and dispersing for 60min under the pressure of 100 MPa;

and S5, filtering the S4 slurry with 800 meshes, and performing centrifugal defoaming to obtain a finished nickel slurry product.

Comparative example 1

The preparation method of the roll printing nickel slurry special for MLCC of the comparison example comprises the following steps:

s1, mixing 2 parts of ethyl cellulose and 98 parts of dihydroterpinyl acetate solvent, heating to 45 ℃, and uniformly stirring in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 30min to obtain an oily binder with the solid content of 2%;

s2, stirring 82.5 parts of nickel powder, 16.5 parts of dihydroterpinyl acetate solvent and 1 part of dispersing auxiliary agent in a high-speed shearing disperser with the rotation speed of 1200rpm for 5min, and then transferring to a nano sand mill with the rotation speed of 3000rpm for grinding for 15min to obtain oily nano nickel dispersion liquid;

s3, stirring 70 parts of nano barium titanate, 2 parts of nano magnesium oxide, 2 parts of nano yttrium oxide, 25 parts of dihydroterpinyl acetate solvent and 1 part of dispersing agent in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, uniformly stirring, transferring to a micro-jet ultrahigh-pressure homogenizer, and grinding for 15min under the pressure of 250MPa to obtain oily nano inorganic filler dispersion liquid;

s4, adding 2 parts of oily closed isocyanate curing agent, 0.5 part of defoaming agent and 0.5 part of flatting agent into 9 parts of the material obtained in S1, 80 parts of the material obtained in S2 and 8 parts of the material obtained in S3, stirring for 15min in a high-speed shearing dispersion machine with the rotating speed of 1200rpm, uniformly transferring the mixture into a high-pressure homogenizer, and dispersing for 60min under the pressure of 100 MPa;

and S5, filtering the S4 slurry by using a 800-mesh filter screen, and performing centrifugal defoaming to obtain a finished nickel slurry product.

Comparative example 2

The preparation method of the roll printing nickel slurry special for MLCC of the comparison example comprises the following steps:

s1, mixing 2 parts of PVB resin with 98 parts of dihydroterpinyl acetate solvent, heating to 45 ℃, stirring for 30min in a high-speed shearing dispersion machine with the rotation speed of 1200rpm, and obtaining an oily binder with the solid content of 2% after uniform mixing;

s2, stirring 82.5 parts of nickel powder, 16.5 parts of dihydroterpinyl acetate solvent and 1 part of oily dispersant uniformly in a high-speed shearing disperser with the rotation speed of 1200rpm for 5min, and then transferring to a nano sand mill with the rotation speed of 3000rpm for grinding for 15min to obtain oily nano nickel dispersion liquid;

s3, stirring 70 parts of nano barium titanate, 2 parts of nano magnesium oxide, 2 parts of nano yttrium oxide, 25 parts of dihydroterpinyl acetate solvent and 1 part of oily dispersant in a high-speed shearing dispersion machine with the rotation speed of 1200rpm for 5min, uniformly stirring, transferring to a micro-jet ultrahigh-pressure homogenizer, and grinding for 15min under the pressure of 250MPa to obtain oily nano inorganic filler dispersion liquid;

s4, adding 2 parts of oily closed isocyanate curing agent, 0.5 part of oily defoaming agent and 0.5 part of oily leveling agent into 9 parts of the material obtained in S1, 80 parts of the material obtained in S2 and 8 parts of the material obtained in S3, stirring uniformly for 15min in a high-speed shearing dispersion machine with the rotating speed of 1200rpm, transferring the mixture into a high-pressure homogenizer, and dispersing for 60min under the pressure of 100 MPa;

and S5, filtering the S4 slurry by using a 800-mesh filter screen, and performing centrifugal defoaming to obtain the finished product nickel slurry.

And (3) detection and test:

for the nickel pastes prepared in examples 1-3 and comparative examples 1-2, 100 (0402X5R105) MLCC products were prepared according to the conventional method, and the electrical properties of all the products were tested under the same conditions, and the test results are shown in Table 1.

Table 1: test table for electrical properties of MLCC products prepared from nickel slurries of examples and comparative examples 1-2

Compared with the conventional MLCC nickel paste, the special roll printing nickel paste for the MLCC has the advantages that the content of VOCs in the nickel paste is greatly reduced, other performances are equivalent to those of the MLCC prepared from the conventional nickel paste, and even the special roll printing nickel paste is slightly superior, and the capacitance value of the MLCC is improved.

Finally, it should be noted that the above-mentioned embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above-mentioned embodiments, it should be understood by those skilled in the art that the modifications and equivalents of the specific embodiments of the present invention can be made by those skilled in the art after reading the present specification, but these modifications and variations do not depart from the scope of the claims of the present application.