CN104934093A - Nano silver powder PCB conductive silver paste and preparation method thereof - Google Patents

Abstract

A nano silver powder PCB conductive silver paste comprises the following raw materials by weight: 5-7 parts of nano gamma-Al2O3 powder, 1-2 parts of polyether amine carrageenan, 40-50 parts of 20-30nm flaky silver powder, 3-4 parts of xylene, 3-4 parts of glycerol, 5-6 parts of octanol, 1-2 parts of vulcanized butyl oleate, 2-3 parts of cyclohexanone, 8-12 parts of glass powder, 1-2 parts of nano zinc oxide, 9-12 parts of thermosetting acrylic resin, 1-2 parts of chitin, and 1-2 parts of ricinoleic acid. Through the use of nanoscale silver powder, the silver paste of the invention has good electrical conductivity, and only a small amount of silver powder is used. The silver paste adopts nano gamma-Al2O3 powder, which makes the circuit have good toughness and high strength and not easy to break. The glass powder is lead-free and environment-friendly, has low melting point, and is easy to cure.

Description

A kind of nano-silver powder PCB conductive silver paste and preparation method thereof

Technical field

The invention belongs to electric slurry technical field, particularly relate to a kind of nano-silver powder PCB conductive silver paste and preparation method thereof.

Background technology

In modern microelectronic industry, people require more and more higher to electronic devices and components, production adopts procedure more, standardization is carried out reducing costs, printed circuit board (PCB) (PCB) is exactly that this demand being applicable to microelectronics industry is born, match with the electric slurry such as resistance slurry, grout slurry and printed circuit board (PCB) (PCB) with regard to the conductor paste of the new requirement of demand, electrode slurry, dielectric paste accordingly, the research carrying out new conductor paste is also just imperative.

In general, the main component of electric slurry includes function mutually as metal, noble metal powder etc., inorganic binder as glass powder, oxide powder etc., organic binder bond, other solvent and additive.Usually, function in electric slurry plays electric action mutually, have good electric conductivity, is generally served as by metal dust or noble metal powder, conventional metal dust has copper powder, aluminium powder, zinc powder, nickel powder etc., and conventional precious metal powder has bronze, silver powder, platinum powder, palladium powder etc.Inorganic binder plays fixing electric slurry to base material, and generally served as by oxide powder and glass powder, but this composition is lower at the proportion of electric slurry, what have does not even have; Organic binder bond mainly works to make slurry have certain shape, is easy to printing or coating, mainly contain macromolecule resin, Small molecular resin etc. to serve as, along with this part effect in electric slurry of progress of chemical industry technology is more and more outstanding, especially, when being applied to silk screen printing, the composition changing organic binder bond just can change the printing of electric slurry, drying, sintering character.

In existing electric slurry field, it is high that silver system slurry has conductance, stable performance, with the feature such as substrate bond strength is large, is widely used in the production of the electronic devices and components such as integrated circuit, multi-chip module, thin film switch.But silver is precious metal, and cost is higher, and the silver powder major part in existing silver paste is micron-sized powder, and the thicknesses of layers, printing performance etc. of its slurry made have significant limitation for present high-end precision instrument; On the other hand, the conductive copper paste of the many employing printings of printed circuit board (PCB) in the past makes conducting wire, but it is easily oxidized to there is conductive copper paste, reduces the useful life of printed circuit board (PCB), and conductive copper paste can not be printed as meticulousr circuit.Therefore need the size of metal dust in research electrocondution slurry, shape, kind to realize the object reducing costs, improve conductance, improve printing accuracy.

Binding agent in conductive silver paste has a significant impact for the rate of finished products of circuit printing, such as the volatility etc. of viscosity, caking property, adhesive force, levelability, film forming, solvent all can impact the printing performance of circuit, there is pore, the phenomenons such as open circuit, also there will be glassy phase after organic substance has volatilized sometimes not yet to start to melt, the phenomenon causing conducting wire to come off from stock, makes conducting wire scrap, and therefore the performance need of organic binder bond improves.

A lot of inorganic binder adopts glass dust at present, glass dust is made up of the material such as metal oxide, silica, if fusing point is too high, also occur organic substance volatilized after glassy phase not yet start melt, the phenomenon causing the conducting wire obtained by conductive silver paste to come off from stock, makes conducting wire scrap; And a lot of containing harmful substances such as lead in current glass dust, unfavorable to environment, therefore need to develop the more excellent glass dust of performance.

Summary of the invention

The object of the present invention is to provide a kind of nano-silver powder PCB conductive silver paste and preparation method thereof, this silver slurry good conductivity, and silver powder consumption is little, the good toughness of circuit, intensity is high, not easy fracture.

Technical scheme of the present invention is as follows:

A kind of nano-silver powder PCB conductive silver paste, is characterized in that being made up of the raw material of following weight portion: γ-Al2O3 nanosized powder end 5-7, polyetheramine carragheen 1-2,20-30nm flake silver powder 40-50, dimethylbenzene 3-4, glycerol 3-4, octanol 5-6, sulfurized oil acid butyl ester 1-2, cyclohexanone 2-3, glass dust 8-12, nano zine oxide 1-2, thermosetting acrylic resin 9-12, chitin 1-2, castor oil acid 1-2;

Described glass dust is made up of the raw material of following weight portion: SiO2 10-13, V2O5 15-18, Sb2O3 5-7, gas phase alundum (Al2O3) 2-4, activated alumina 15-18, P2O5 4-6, anoxic cerium oxide 3-6, MgO2-3, four acicular type zinc oxide crystal whisker 2-4; Preparation method is: by SiO2, V2O5, Sb2O3, gas phase alundum (Al2O3), activated alumina, P2O5, anoxic cerium oxide, MgO mixing, put into crucible and become liquid 1100-1400 DEG C of heat fused, add four acicular type zinc oxide crystal whisker again, carry out vacuum defoamation after stirring, vacuum degree is 0.10-0.14MPa, and inclined heated plate is 6-9 minute, pour in mould again and shape, carry out shrend again, send into pulverizing in ball mill, sieve, obtain 7-10 μm of powder, to obtain final product.

The preparation method of described nano-silver powder PCB conductive silver paste, is characterized in that comprising the following steps:

(1) by dimethylbenzene, chitin, castor oil acid, glycerol, octanol, sulfurized oil acid butyl ester, cyclohexanone mixing, add thermosetting acrylic resin, be heated to 80-84 DEG C, be stirred to resin all to dissolve, add polyetheramine carragheen again to stir, filter with 500 object gauzes, removing impurity obtains organic carrier;

(2) by glass dust, nano zine oxide mixing, γ-Al2O3 nanosized powder end is added under stirring at 5000-7000 rev/min, stir 10-20 minute, add 20-30nm flake silver powder again, stir 10-20 minute, then add in organic carrier together with other residual componentss, mixing dispersion 30-50 minute in ball mill, ultrasonic disperse 6-8 minute again, obtains uniform slurry;

(3) slurry that step (2) obtains is carried out vacuum defoamation, vacuum degree is 0.06-0.09MPa, and inclined heated plate is 6-9 minute, then carries out grinding in three-high mill, rolling, is 10000-20000 centipoise, obtains final product to silver-colored slurry viscosity.

Beneficial effect of the present invention

Silver slurry of the present invention is by using nano-scale silver powder, good conductivity, and silver powder consumption is little; The present invention's silver slurry employs γ-Al2O3 nanosized powder end, and make the good toughness of circuit, intensity is high, not easy fracture; Glass dust leadless environment-friendly of the present invention, fusing point is low, easy curing molding.

Embodiment

A kind of nano-silver powder PCB conductive silver paste, is made up of the raw material of following weight portion (kilogram): γ-Al2O3 nanosized powder end 6, polyetheramine carragheen 1.5,20-30nm flake silver powder 45, dimethylbenzene 3.5, glycerol 3.5, octanol 5.5, sulfurized oil acid butyl ester 1.5, cyclohexanone 2.5, glass dust 10, nano zine oxide 1.5, thermosetting acrylic resin 11, chitin 1.5, castor oil acid 1.5;

Described glass dust is made up of the raw material of following weight portion (kilogram): SiO2 11, V2O5 17, Sb2O3 6, gas phase alundum (Al2O3) 3, activated alumina 17, P2O5 5, anoxic cerium oxide 4, MgO2.5, four acicular type zinc oxide crystal whisker 3; Preparation method is: by SiO2, V2O5, Sb2O3, gas phase alundum (Al2O3), activated alumina, P2O5, anoxic cerium oxide, MgO mixing, put into crucible, become liquid 1300 DEG C of heat fused, then add four acicular type zinc oxide crystal whisker, after stirring, carry out vacuum defoamation, vacuum degree is 0.12MPa, inclined heated plate is 7 minutes, then pours in mould and shape, then carries out shrend, sends in ball mill and pulverize, sieve, obtain 9 μm of powder, to obtain final product.

The preparation method of described nano-silver powder PCB conductive silver paste, comprises the following steps:

(1) by dimethylbenzene, chitin, castor oil acid, glycerol, octanol, sulfurized oil acid butyl ester, cyclohexanone mixing, add thermosetting acrylic resin, be heated to 82 DEG C, be stirred to resin all to dissolve, add polyetheramine carragheen again to stir, filter with 500 object gauzes, removing impurity obtains organic carrier;

(2) by glass dust, nano zine oxide mixing, γ-Al2O3 nanosized powder end is added under stirring at 6000 revs/min, stir 15 minutes, add 20-30nm flake silver powder again, stir 15 minutes, then add in organic carrier together with other residual componentss, in ball mill, mix dispersion 40 minutes, ultrasonic disperse 7 minutes, obtains uniform slurry again;

(3) slurry that step (2) obtains is carried out vacuum defoamation, vacuum degree is 0.08MPa, and inclined heated plate is 8 minutes, then carries out grinding in three-high mill, rolling, is 15000 centipoises, obtains final product to silver-colored slurry viscosity.

Test data:

The mode of the silver slurry silk screen printing obtained by the present embodiment is printed onto in PCB, solidifies and forms conducting wire in 6 minutes, thus obtain conducting wire plate at being then warming up to 640 DEG C.The wiring width recording conducting wire is 0.7mm, average film thickness 5 μm, and wire distribution distance is 0.7mm, and resistivity is 4-4.9 × 10 ^-5Ω m.

Produce conducting wire plate 1000 pieces in batches in the manner described above, conducting wire is combined with PCB well, svelteness, continuously, has the conducting wire of 5 pieces of circuit boards to come off from stock, rate of finished products 99.5%.

Claims (2)

1. a nano-silver powder PCB conductive silver paste, is characterized in that being made up of the raw material of following weight portion: γ-Al2O3 nanosized powder end 5-7, polyetheramine carragheen 1-2,20-30nm flake silver powder 40-50, dimethylbenzene 3-4, glycerol 3-4, octanol 5-6, sulfurized oil acid butyl ester 1-2, cyclohexanone 2-3, glass dust 8-12, nano zine oxide 1-2, thermosetting acrylic resin 9-12, chitin 1-2, castor oil acid 1-2;

Described glass dust is made up of the raw material of following weight portion: SiO2 10-13, V2O5 15-18, Sb2O3 5-7, gas phase alundum (Al2O3) 2-4, activated alumina 15-18, P2O5 4-6, anoxic cerium oxide 3-6, MgO2-3, four acicular type zinc oxide crystal whisker 2-4; Preparation method is: by SiO2, V2O5, Sb2O3, gas phase alundum (Al2O3), activated alumina, P2O5, anoxic cerium oxide, MgO mixing, put into crucible and become liquid 1100-1400 DEG C of heat fused, add four acicular type zinc oxide crystal whisker again, carry out vacuum defoamation after stirring, vacuum degree is 0.10-0.14MPa, and inclined heated plate is 6-9 minute, pour in mould again and shape, carry out shrend again, send into pulverizing in ball mill, sieve, obtain 7-10 μm of powder, to obtain final product.

2. the preparation method of nano-silver powder PCB conductive silver paste according to claim 1, is characterized in that comprising the following steps:

(1) by dimethylbenzene, chitin, castor oil acid, glycerol, octanol, sulfurized oil acid butyl ester, cyclohexanone mixing, add thermosetting acrylic resin, be heated to 80-84 DEG C, be stirred to resin all to dissolve, add polyetheramine carragheen again to stir, filter with 500 object gauzes, removing impurity obtains organic carrier;

(2) by glass dust, nano zine oxide mixing, γ-Al2O3 nanosized powder end is added under stirring at 5000-7000 rev/min, stir 10-20 minute, add 20-30nm flake silver powder again, stir 10-20 minute, then add in organic carrier together with other residual componentss, mixing dispersion 30-50 minute in ball mill, ultrasonic disperse 6-8 minute again, obtains uniform slurry;

(3) slurry that step (2) obtains is carried out vacuum defoamation, vacuum degree is 0.06-0.09MPa, and inclined heated plate is 6-9 minute, then carries out grinding in three-high mill, rolling, is 10000-20000 centipoise, obtains final product to silver-colored slurry viscosity.