Titanium dioxide is the coating film material can notonly make the coated surface bright white, but also can enhance coating abilityof weathering resistance, resistance to pulverization and rheologicalproperty.Realize the factors influencing the titanium dioxide dispersion in thecoating, not only can improve the quality of coating, can also reduce pollutionemissions, make cleaning industry for better implementation of the country.

1.The influencing factors of dispersion

In solventpaint, the application and performance characteristics of titanium dioxidedecided the dispersion and the decentralized stabilizationof titanium dioxidein the resin and solvent oil performance.

Firstly,Theaverage particle size and particle size distribution property of titanium whitepigment.When the quality of titanium dioxide particle size less than 200 nmpercentage is about 30%, Zeta potential around - 70 mv;If the qualitypercentage is less than 20%, the Zeta potential around - 40 mv,so titaniumdioxide particle size of the serious influence the surface electrical,thenaffects surface adsorption performance.The partical size can’t toosmall,otherwise it will affect the other performance of the titanium dioxide,the best control granularity in Lm (0115 ~ 013).

Second,soluble matter content of titanium dioxide application performance.In mixedcoating dispersed system, strong polarity inorganic ions will not only offsetthe charge on the surface of the titanium dioxide, and unable to form apowerful electric double layer, the adsorption on the surface of the titaniumdioxide is abate, the resin can't firmly adsorbed on the surface of titaniumdioxide particles,Reducing the titanium pigment dispersion stabilization,causing them to return to coarse in solvent coatings.

Finally,thehigh and low of oil absorption impact titanium dioxide dispersion anddispersion stability.High oil absorption of the titanium dioxide grinding afterdispersion, part of solvent oil will be absorbed by titanium dioxide and makeless than the oil soluble resin resin solvation degree is reduced, weaken thetitanium dioxide adsorption, results in the decrease of the dispersion anddispersion stability.

2.Forimprovement of the dispersion

(1)Strictcontrol of particle size and size distribution.

Factorsaffecting titanium pigment particle size and size distribution is morecomplicated it is difficult to fully grasp, so first of all, to improve thehydrolysis process and technology to ensure that the uniform particlesgenerated the original level.Secondly to reinforce titanium dioxide particlesuniform growth calcined critical temperature point of control.The final productof shatter, select high efficiency and good classification effect jet millinstead of Raymond system to stable titanium white surface features.

(2)Strictlycontrol the oil absorption and water insoluble substance

Titaniumdioxide oil absorption with calcination atmosphere in the sintering process andhigh temperature calcining temperature.If improper control.So,Must control theappropriate calcination temperature to adjust feed rate and rotational speed ofkiln body is reasonable matching, thus reducing the particles of latticedefects and rule the geometric shape of particles.

3.Strictsurface treatment

At present,most of Chinese paint manufacturers coating with a anatase grade titaniumdioxide, its dispersion in the coating is poorer,industry under the backgroundof the state advocates the clean, rutile type titanium dioxide application incoatings industry gradually replace anatase type titanium dioxide.To still useanatase titanium pigment coating enterprise, can change its surface propertiesby surface treatment, such as choosing organic silicon and nitrogen couplingreagent or some polyphosphate, etc.

　　Dispersion is one of the most importantindicators in titanium dioxide production.Dispersion is not good, not onlyaffect the effect of titanium dioxide and pollution will also increase.With thehigh-speed development of economy and policy in our country, especially moreperfect of environmental policy, especially related to titanium dioxideindustry changing paint manufacturing and it to titanium dioxide industry inChina has brought unprecedented opportunities and challenges.Therefore,Titaniumdioxide enterprises should carefully study the product performance,in a timelymanner to improve production technology and the ramming foundation.Let thenational policy change from resistance thrust achieve the stability of theenterprise.