CN1182107A

CN1182107A - Outer conductive paint for glass bulb of display tube and its preparation

Info

Publication number: CN1182107A
Application number: CN 96120475
Authority: CN
Inventors: 马忠好
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-11-13
Filing date: 1996-11-13
Publication date: 1998-05-20

Abstract

The conductive paint is prepared by using graphite with size smaller than 30 micoron as main material, dispersing agent, adhesive, film forming agent and ammonia water as supplementary material as well as water, which densifier and surfactant may be also added. The preparation process includes pretreatment of partial material in vibration mill for 8-12 hr, emulsification of all material in ball mill for 6-14 hr and sieving. The conductive paint thus prepared has high uniformity, good dispersivity, high long-period stability and low film resistance.

Description

Outer conductive paint for glass bulb of display tube and preparation method thereof

The present invention relates to a kind of electrically conducting coating and preparation method thereof, more specifically, relate to a kind of picture tube or show outer graphite mould electrically conducting coating of tube glass cone and preparation method thereof.

At present, in the reinforcement operation of producing picture tube or typotron, the outer electrically conducting coating of pipe glass awl is using a kind of aquadag, and the subject matter of its existence is to place the long period postprecipitation to weigh, and shaking up property is poor, thereby is unfavorable for using very much.

The purpose of this invention is to provide a kind of picture tube or show the prescription and preparation method thereof of the electrically conducting coating of tube glass cone external application, the described aquadag precipitation that it can solve prior art heavily reaches the problem of shaking up property difference.

Technical solution of the present invention is: electrically conducting coating of the present invention has following prescription, is 100% with finished weight, contained each composition weight percent:

Major ingredient is graphite 25-29%;

Auxiliary material has diffusant 0.3-1%, serves as preferred with 0.8%;

Cement 5-15% serves as preferred with 10%;

Membrane-forming agent 10-15% serves as preferred with 12%;

Ammoniacal liquor 0.5-1% is preferred with 0.5-0.6%;

All the other are water.

Wherein, graphite can be used amorphous graphite, crystalline flake graphite or synthetic graphite, is preferred with the crystalline flake graphite, and granularity should be less than 30 microns.The carbon black that can add the total formulation weight 2-5% of coating replaces the graphite of equivalent weight, and carbon black loading is best with 2-3%.

Described diffusant can be selected the two sodium naphthalene sulfonates (NNO) of methylene radical methylnaphthalene, carboxymethyl cellulose (CMC) and suitable material for use.

Described cement can be selected from one of silicon sol, potassium silicate, water glass, lithium silicate.

Described membrane-forming agent is a styrene acrylic resin, can be that the trade mark that the styrene-acrylonitrile copolymer acid butyl ester is polymerized is the material of TB-01 (Richu Group Co., Jiangsu's production), BC-01 (production of Yantai chemical general factory) or PC-01 (Dongfang Chemical Plant, Beijing, The East Chemical Plant,Beijing's production), or the trade mark that the styrene acrylic methyl esters is polymerized be the material of TL-1 (Richu Group Co., Jiangsu's production).

Ammoniacal liquor is used for adjusting the pH value of coating of the present invention, with analytically pure ammoniacal liquor for well.

In order to increase the denseness of coating of the present invention, can use thickening material, usage quantity is the 0.2-0.6% of coating total amount, serves as preferred with 0.2%.Described thickening material can be aforesaid CMC.

May exist under the smeary situation on the surface of picture tube or typotron, in order to strengthen the ADHESION OF PAINTS ability, can increase tensio-active agent in prescription, its consumption is the 0.1-1% of coating total amount, serves as preferred with 0.1%.Tensio-active agent can be the styrene maleic acid resin.

The preparation method of electrically conducting coating of the present invention is made up of following steps:

1. with graphite or graphite and carbon black loading 65%, the diffusant consumption 40%, 40% and water consumption of ammonia volume be mixed with raw material for the first time as feeding intake for the first time;

2. pre-treatment: use in colloidal mill, vibration mill, ball mill or the sand mill a kind of to the first time raw material handled 8-12 hour, preferably use vibration mill, the treatment time served as preferred with 10 hours;

3. emulsification: the surplus of graphite or graphite and carbon black, diffusant and ammoniacal liquor and membrane-forming agent, cement consumption are mixed with for the second time raw material add in pretreated first time raw material as feeding intake for the second time, use a kind of emulsification of carrying out in colloidal mill, stirrer, vibration mill, the ball mill, the preferred ball mill that uses, treatment time is 6-14 hour, serves as preferred with 8 hours;

4. sieve: remove impurity, promptly become finished product coating.

In this preparation method, for the prescription scheme of using thickening material CMC, then in feeding intake for the first time, add 50% of thickening material consumption and participate in pre-treatment, during feeding intake for the second time, its surplus thickening material adding participates in emulsification.

In the prescription scheme of using tensio-active agent, then tensio-active agent is added in the work in-process after the emulsification and stir evenly, be screened into finished product then.

With the outer conductive paint for glass bulb of display tube that prescription of the present invention and preparation method form, because the character of graphite obtains improvement, granularity attenuates, free settling not in the finished product material.Because the emulsification process among the preparation method of the present invention makes the fully emulsified combination of main materials and auxiliary materials, has improved the stability of product, become a kind of good dispersity, electrically conducting coating that foaming is few, satisfactoryly solved the problem that the situation that shakes up is poor, precipitation is heavy that prior art exists.Through sample, in a small amount, the actual importing of middle amount test back proving effect is good, it is sprayed on back, pipe glass awl outside and forms the uniform conductive film, and with inner face graphite linings formation electric capacity.Engineering characteristic and the characteristic after the envrionment test in the physicochemical property of itself, the use all are better than existing coating.Its advantage is 1. easily to shake up, prevented from caking, good dispersity; 2. peculiar smell is little; 3. shake or roll the back foam few; 4. it is strong to spray dry postadhesion power; 5. resistance is low after spraying film forming; 6. place stable performance after the long period.

Several embodiment below are provided.The prescription of embodiment is 100% heavy per-cent with finished product material weight.

	Example 1	Example 2	Example 3	Example 4	Example 5
	Example 1	Example 2	Example 3	Example 4	Example 5	Graphite	????29	????25	????25	????27	????24
Carbon black		????2			????5	Graphite	????29	????25	????25	????27	????24
Carbon black		????2			????5	????NN0	????1	????0.3	????0.5	????0.8	????0.5
Silicon sol	????10	????15	????10	????12	????5	????NN0	????1	????0.3	????0.5	????0.8	????0.5
Silicon sol	????10	????15	????10	????12	????5	????BC-01	????12	????10			????15
????TL-1			????15	????12		????BC-01	????12	????10			????15
????TL-1			????15	????12		Analytical pure ammoniacal liquor	????1	????0.5	????0.5	????0.6	????0.8
The styrene maleic acid resin			????0.1		????1	Analytical pure ammoniacal liquor	????1	????0.5	????0.5	????0.6	????0.8
The styrene maleic acid resin			????0.1		????1	????CMC			????0.2
Water	All the other	All the other	All the other	All the other	All the other	????CMC			????0.2

Each embodiment coating detects amount of solid content 32-38%, and viscosity is between the 300-500 centipoise, and resistance value is less than 100 Ω/10cm, and it is qualified that other are all examined in being coated with the pipe test as cohesive force, water tolerance.

Claims

1. outer conductive paint for glass bulb of display tube, it is characterized in that: with finished product material weight is 1, each composition percentage composition is

Granularity is less than 30 microns graphite 25-29;

Diffusant 0.3-1; With 0.8 is preferred value;

Cement 5-15; With 10 is preferred value;

Membrane-forming agent 10-15; With 12 is preferred value;

Ammoniacal liquor 0.5-1; With 0.5-0.6 is preferred value;

Water all the other,

2. electrically conducting coating according to claim 1 is characterized in that with accounting for the 2-5% of finished product material weight, and wherein 2-3% is the graphite that the carbon black of preferable range replaces same quantity.

3. electrically conducting coating according to claim 1 and 2 is characterized in that described graphite is a kind of in amorphous graphite, crystalline flake graphite or the synthetic graphite; With the crystalline flake graphite is preferred.

4. electrically conducting coating according to claim 1 and 2, the thickening material of adding finished product material weight 0.2-0.6% in it is characterized in that filling a prescription; With 0.2% is preferred value.

5. electrically conducting coating according to claim 4 is characterized in that it is carboxymethyl cellulose that thickening material advances in institute.

6. electrically conducting coating according to claim 1 and 2 is characterized in that described diffusant is two sodium naphthalene sulfonate, perhaps carboxymethyl celluloses of methylene radical methylnaphthalene; Described cement be silicon sol, water glass, and lithium silicate in a kind of; Described membrane-forming agent is a styrene acrylic resin.

7. electrically conducting coating according to claim 1 and 2 is characterized in that also adding tensio-active agent in the prescription, and consumption is the 0.1-1% of finished product material weight; With 0.1% serves as preferred; Described tensio-active agent can be the styrene maleic acid resin.

8. electrically conducting coating according to claim 1 and 2 is characterized in that described ammoniacal liquor is analytically pure.

9. the preparation method of an outer conductive paint for glass bulb of display tube is characterized in that being made up of following steps:

1. with 65% of graphite or graphite and carbon black loading, 40% of diffusant consumption, 40% of ammonia volume, and the consumption of water is mixed with raw material for the first time for feeding intake for the first time;

2. pre-treatment: use in colloidal mill, vibration mill, ball mill or the sand mill a kind of to the first time raw material handled 8-12 hour; The preferred vibration mill that uses; Treatment time served as preferred with 10 hours;

3. emulsification: the surplus of graphite or graphite and carbon black, diffusant and ammoniacal liquor and membrane-forming agent, cement consumption are mixed with for the second time raw material add in pretreated first time raw material as feeding intake for the second time, use a kind of emulsification of carrying out in colloidal mill, stirrer, vibration mill, the ball mill; The preferred ball mill that uses; Treatment time is 6-14 hour; With 8 hours served as preferred;

4. sieve: remove impurity, promptly become finished product coating.

10. preparation method according to claim 9 is characterized in that:

For the prescription that uses thickening material half of adding thickening material consumption in 1. described step feeds intake for the first time; Adding all the other half in 3. step feeds intake for the second time;

For the prescription that uses tensio-active agent, 3. described tensio-active agent adds the emulsification back that finishes in described step, stirs evenly, and performing step 4. then.