Characteristics of Titanium Dioxide Used in Paper Making Industry

Papermaking is the third largest user of titanium dioxide. Titanium dioxide is generally not used in low-grade paper due to production cost considerations. China clay, talcum powder, calcium carbonate, etc. are mainly used, but they will reduce the strength of the paper and increase the weight of the paper. Titanium dioxide must be used in decorative paper, Bible paper and banknotes (such as dictionaries, illustrated magazines, magazine covers, computers, banknotes, copier paper and decorative paper, etc.). Paper using titanium dioxide has good whiteness, high strength, glossy, thin and smooth, and does not penetrate when printing. Under the same conditions, the opacity is 10 times higher than calcium carbonate and talc powder, and the weight can also be reduced by 15% to 30%.

Decorative paper, also called titanium dioxide paper, is mainly used to make furniture, flooring, wallpaper and other raw materials. For papers with anti-aging requirements, rutile must be used; more rutile is used in high-ash content paper. This high-ash content paper must use rutile because the hiding power of anatase titanium dioxide does not meet the requirements. . Anatase titanium dioxide is used in low-ash paper, such as Bible paper and banknotes. Bible paper requires the paper to have good opacity, which can generally be met by using anatase titanium dioxide; coinage paper also requires very good opacity. Good opacity, mostly using anatase type too. In China, the amount of titanium dioxide used in decorative paper is much higher than the other two varieties. This situation is determined by my country's consumption level. Due to the large demand for house decoration and high-end furniture, the use of decorative paper has gradually increased; because Bible paper uses titanium dioxide as raw material, the cost is much higher than that of ordinary paper. In view of domestic consumption levels, the market for Bible paper is very limited; and the manufacturing of Bible paper The manufacturing and use of banknotes are controlled by the state, and the usage is relatively stable and will not have an impact on the titanium dioxide market. According to incomplete estimates, domestic titanium dioxide used for decorative paper exceeds 30,000 tons per year. The dosage of titanium dioxide in decorative paper is 20 to 40%, and that in other papers is 1 to 5%. As traditional cultural paper manufacturers have transformed into the production of decorative paper, the output of decorative paper has grown rapidly, and the price of decorative paper has shown a downward trend in recent years.

No matter what kind of paper (base paper), the production process is the same. Rutile is used for weather-resistant, high-ash content paper, and anatase type is used for paper with low weather-resistant requirements and low ash content. The main reason for deciding which titanium dioxide to choose for a paper mill is the cost of papermaking, that is, the cost-effectiveness of titanium dioxide. . Since the cost proportion of titanium dioxide in papermaking is as high as 30 to 50%, paper mills are very careful about choosing titanium dioxide when meeting user requirements. They will never use rutile if they can use anatase type. The papermaking industry’s requirements for titanium dioxide quality, in order of importance, are:

1）Hiding power: The ability of paper containing the same titanium dioxide to cover the background color. This indicator determines the cost-effectiveness of titanium dioxide. To put it simply, titanium dioxide with high hiding power generally has a high price but is used in small quantities, so the cost of titanium dioxide per ton of paper may be lower; titanium dioxide with low covering power, although the price is low, is used in large quantities, resulting in a low cost per ton of paper. The cost of titanium dioxide in paper increases.

2）Whiteness: The whiteness of titanium dioxide determines the appearance of the paper after molding.

3）Dispersibility: Current papermaking processes generally use dispersants, so the water dispersibility of titanium dioxide is not much different.

4）Weather resistance: Domestic rutile can meet the weather resistance requirements of most papers, and only a few papers require rutile to provide high weather resistance.

5）Retention rate: The papermaking industry reuses filtered water or uses retention aids. Generally, the recovery rate of titanium dioxide is above 99%. The reason why this indicator is retained is because the major international titanium dioxide companies are promoting it. Special titanium dioxide for papermaking is also provided with retention aid formulas and usage methods to improve service quality and increase product competitiveness.