CN104575665A - Low-viscosity electric conduction silver paste - Google Patents

Abstract

The invention discloses a low-viscosity electric conduction silver paste. The silver paste consists of the following raw materials in parts by weight: 75-80 parts of cladding silver powder, 0.1-0.2 part of bismuth oxide, 0.5-1 part of an ascorbic acid, 0.8-1 part of ferrous sulfate, 2-3 parts of tributyl phosphate, 0.1-0.2 part of glycerin fatty acid ester, 1-2 parts of butyl benzyl phthalate, 0.6-1 part of modified soda, 0.1-0.2 part of hexamethyl disiloxane, 12-16 parts of epoxy resin E51, 23-30 parts of acetone, 0.4-1 part of potassium zirconium carbonate, and 10-15 parts of lead-free glass powder. The cladding silver powder is obtained by enabling nanometer silver powder to be uniformly and compactly clad to the surfaces of macromolecular microspheres, so that not only can the consumption of noble metal silver powder be reduced and the production cost be lowered, but also the dispersibility and the stability of the nanometer silver powder are greatly improved.

Description

A kind of low viscosity conductive silver paste

Technical field

The present invention relates generally to conductive silver paste field, particularly relates to a kind of low viscosity conductive silver paste.

Background technology

Conductive silver slurry refers to and is printed on conduction stock, and making it the silver slurry having conduction current and get rid of accumulate static charge ability, is generally be imprinted on the non-conductive stocks such as plastics, glass, pottery or cardboard.Printing process is very wide, as silk screen printing, letterpress, flexographic printing, intaglio printing and offset printing etc. all can adopt.Then resistance, Solder resistance and rub resistance etc. are also different can to select different printing processes, thickness difference according to the requirement of thickness.This silver slurry has thick film mill base and resin type two kinds.The former is that the high temperature of binder burns till type with frit, the latter take synthetic resin as the low temperature drying of binder or the silk screen silver slurry of radiation-curable, and in conductive filler conductivity it is preferred that silver powder and copper powder, but cost is relatively high, therefore find through experiment, adopt silver-colored coated particle just can to effectively reduce cost as conductive filler, and its its conductivity is had no significant effect.

Summary of the invention

The object of the invention is just to provide a kind of low viscosity conductive silver paste.

The present invention is achieved by the following technical solutions:

A kind of low viscosity conductive silver paste, is characterized in that what it was made up of the raw material of following weight parts:

Coated silver powder 75-80, bismuth oxide 0.1-0.2, ascorbic acid 0.5-1, ferrous sulfate 0.8-1, tributyl phosphate 2-3, fatty acid glyceride 0.1-0.2, BBP(Butyl Benzyl Phthalate 1-2, sodium sesquicarbonate 0.6-1, HMDO 0.1-0.2, epoxy resin E51 12-16, acetone 23-30, potassium zirconium carbonate 0.4-1, lead-free glass powder 10-15;

Described coated silver powder is made up of the raw material of following weight parts:

Nano-sized iron oxide 4-6, lanthanum sulfate 0.1-0.2, deionized water 300-400, butyl acrylate 10-13, sodium carboxymethylcellulose 0.9-2, silane coupler KH560 0.06-0.1, benzoyl peroxide 0.01-0.02, ascorbic acid 45-60, locust bean gum 1-2, sodium tetraborate 0.1-0.14, silver nitrate 100-110;

By nano-sized iron oxide, butyl acrylate mixing, add 31-35%, the sodium carboxymethylcellulose of above-mentioned deionized water weight, benzoyl peroxide is added after stirring, reaction 6-10 hour is left standstill at 70-90 DEG C, add lanthanum sulfate, silane coupler KH560, magnetic agitation 10-15 minute, obtains nanoemulsions;

By locust bean gum, sodium tetraborate mixing, add the 20-30% of residue deionized water weight, drip ammoniacal liquor, adjustment PH is 6.8-7, adds ascorbic acid, stirs, obtain reducing solution;

The mixing of each raw material will be remained, stir, obtain oxidation solution;

Above-mentioned oxidation solution is added drop-wise in reducing solution, nanoemulsions is added after dropwising, rotating speed be 1200-1500rmp, temperature be 20-25 DEG C at dispersed with stirring 25-30 minute, after sedimentation 1-2 hour, supernatant is gone to get its sediment, wash 3-5 time with deionized water and ethanol, dry, abrasive dust.

The preparation method of described low viscosity conductive silver paste, is characterized in that comprising the following steps:

(1) epoxy resin E51 is joined in acetone, stir, add BBP(Butyl Benzyl Phthalate, at 70-80 DEG C, be uniformly mixed 5-10 minute, obtain organic carrier;

(2) by sodium sesquicarbonate, ascorbic acid mixing, stir, add fatty acid glyceride, be uniformly mixed 3-5 minute at 70-75 DEG C, add HMDO, 100-200 rev/min of dispersed with stirring 2-3 minute, add ferrous sulfate, stir, obtain dispersant;

(3) join in organic carrier by coated silver powder, mix, add dispersant and each raw material of residue, high speed dispersion, send on three-roll grinder and mix, ground slurry granularity, to 8-15 micron, gets product.

Advantage of the present invention is:

The nano-silver powder that coated silver powder of the present invention is evenly and is densely coated on the surface of polymer microsphere, not only can reduce the consumption of noble metal silver powder, reduce production cost, also substantially increase dispersiveness and the stability of nano-silver powder simultaneously, adopt the mixing of locust bean gum, sodium tetraborate as dispersant, viscosity is low, is convenient to washing and filtering, good dispersion, not easily forms reunion;

The bismuth oxide that the present invention adds can change the hardness of rete, the viscosity of slurry, and the dispersant added also can improve slurry viscosity, prevents from reuniting, and improves electric conductivity.

Embodiment

Embodiment 1

A kind of low viscosity conductive silver paste, is characterized in that what it was made up of the raw material of following weight parts:

Coated silver powder 80, bismuth oxide 0.2, ascorbic acid 0.5, ferrous sulfate 1, tributyl phosphate 2, fatty acid glyceride 0.2, BBP(Butyl Benzyl Phthalate 2, sodium sesquicarbonate 1, HMDO 0.2, epoxy resin E51 16, acetone 30, potassium zirconium carbonate 0.4, lead-free glass powder 15;

Described coated silver powder is made up of the raw material of following weight parts:

Nano-sized iron oxide 6, lanthanum sulfate 0.2, deionized water 400, butyl acrylate 13, sodium carboxymethylcellulose 0.9, silane coupler KH560 0.06, benzoyl peroxide 0.02, ascorbic acid 60, locust bean gum 2, sodium tetraborate 0.14, silver nitrate 110;

By nano-sized iron oxide, butyl acrylate mixing, add 35% of above-mentioned deionized water weight, sodium carboxymethylcellulose, after stirring, add benzoyl peroxide, reaction 6 hours are left standstill at 70 DEG C, add lanthanum sulfate, silane coupler KH560, magnetic agitation 15 minutes, obtains nanoemulsions;

By locust bean gum, sodium tetraborate mixing, add 30% of residue deionized water weight, drip ammoniacal liquor, regulate PH to be 6.8, add ascorbic acid, stir, obtain reducing solution;

The mixing of each raw material will be remained, stir, obtain oxidation solution;

Above-mentioned oxidation solution is added drop-wise in reducing solution, add nanoemulsions after dropwising, rotating speed be 1200rmp, temperature be 25 DEG C at dispersed with stirring 30 minutes, supernatant goes after 2 hours to get its sediment by sedimentation, 5 times are washed, dry, abrasive dust with deionized water and ethanol.

The preparation method of described low viscosity conductive silver paste, comprises the following steps:

(1) epoxy resin E51 is joined in acetone, stir, add BBP(Butyl Benzyl Phthalate, at 80 DEG C, be uniformly mixed 10 minutes, obtain organic carrier;

(2) by sodium sesquicarbonate, ascorbic acid mixing, stir, add fatty acid glyceride, be uniformly mixed 5 minutes, add HMDO at 75 DEG C, 200 revs/min of dispersed with stirring 3 minutes, add ferrous sulfate, stir, obtain dispersant;

(3) join in organic carrier by coated silver powder, mix, add dispersant and each raw material of residue, high speed dispersion, send on three-roll grinder and mix, ground slurry granularity to 15 micron, gets product.

Performance test:

Without lump, in uniform state after stirring;

Fineness≤15 μm;

Adhesive force 4.8B;

Hardness 1H.

Claims (2)

1. a low viscosity conductive silver paste, is characterized in that what it was made up of the raw material of following weight parts:

Coated silver powder 75-80, bismuth oxide 0.1-0.2, ascorbic acid 0.5-1, ferrous sulfate 0.8-1, tributyl phosphate 2-3, fatty acid glyceride 0.1-0.2, BBP(Butyl Benzyl Phthalate 1-2, sodium sesquicarbonate 0.6-1, HMDO 0.1-0.2, epoxy resin E51 12-16, acetone 23-30, potassium zirconium carbonate 0.4-1, lead-free glass powder 10-15;

Described coated silver powder is made up of the raw material of following weight parts:

Nano-sized iron oxide 4-6, lanthanum sulfate 0.1-0.2, deionized water 300-400, butyl acrylate 10-13, sodium carboxymethylcellulose 0.9-2, silane coupler KH560 0.06-0.1, benzoyl peroxide 0.01-0.02, ascorbic acid 45-60, locust bean gum 1-2, sodium tetraborate 0.1-0.14, silver nitrate 100-110;

By nano-sized iron oxide, butyl acrylate mixing, add 31-35%, the sodium carboxymethylcellulose of above-mentioned deionized water weight, benzoyl peroxide is added after stirring, reaction 6-10 hour is left standstill at 70-90 DEG C, add lanthanum sulfate, silane coupler KH560, magnetic agitation 10-15 minute, obtains nanoemulsions;

By locust bean gum, sodium tetraborate mixing, add the 20-30% of residue deionized water weight, drip ammoniacal liquor, adjustment PH is 6.8-7, adds ascorbic acid, stirs, obtain reducing solution;

The mixing of each raw material will be remained, stir, obtain oxidation solution;

Above-mentioned oxidation solution is added drop-wise in reducing solution, nanoemulsions is added after dropwising, rotating speed be 1200-1500rmp, temperature be 20-25 DEG C at dispersed with stirring 25-30 minute, after sedimentation 1-2 hour, supernatant is gone to get its sediment, wash 3-5 time with deionized water and ethanol, dry, abrasive dust.

2. a preparation method for low viscosity conductive silver paste as claimed in claim 1, is characterized in that comprising the following steps:

(1) epoxy resin E51 is joined in acetone, stir, add BBP(Butyl Benzyl Phthalate, at 70-80 DEG C, be uniformly mixed 5-10 minute, obtain organic carrier;

(2) by sodium sesquicarbonate, ascorbic acid mixing, stir, add fatty acid glyceride, be uniformly mixed 3-5 minute at 70-75 DEG C, add HMDO, 100-200 rev/min of dispersed with stirring 2-3 minute, add ferrous sulfate, stir, obtain dispersant;

(3) join in organic carrier by coated silver powder, mix, add dispersant and each raw material of residue, high speed dispersion, send on three-roll grinder and mix, ground slurry granularity, to 8-15 micron, gets product.