As we all know, Titanium Dioxide, with its excellent performance, has become the most widely used white pigment, coating, papermaking, plastics
1、 Application of titanium dioxide in coatings
The coating is used on the surface of various products, playing the role of outer layer protection and beautiful color. Titanium dioxide is widely used in the coating to improve the chemical stability of the coating, improve its hiding power, weather resistance and corrosion resistance. In addition, the addition of titanium dioxide can also enhance the adhesion of the coating film on the device surface, improve the mechanical strength of the coating film, expand the application range and prolong the service life.
In the paint industry, the paint is usually coated on a black and white background, and the reflectance of the two is measured with a spectrophotometer. The ratio represents the hiding power. The higher the ratio, the stronger the hiding power. The hiding power is related to the light scattering, and the light scattering is closely related to the particle size of titanium dioxide, that is, when the particle size is 0.2~0.3 μ M (about half of the incident light wavelength), titanium dioxide can produce the best light scattering rate and the best hiding power.
However, the agglomeration effect of particles often makes the particle size of titanium dioxide in the coating matrix larger than the optimal particle size, so surface modification is often used to ensure the particle size. In addition to the relevant modification methods summarized above, it can also be compounded with other White Pigments, and the structural difference of double pigment particles can be used to ensure the particle size of titanium dioxide and further improve the light scattering rate, so as to improve the hiding power of pigments.
2、 Application of titanium dioxide in plastics
The plastic industry is the second largest user of titanium dioxide, and the pace of plastic replacing steel is accelerating. As the basic pigment of plastics, the demand for titanium dioxide is also increasing year by year. Adding a certain amount of titanium dioxide to plastics can not only improve the whiteness and hiding power of plastic products, but also improve the light, heat and weather resistance of plastic products, and improve the mechanical and electrical properties of plastics.
Due to the poor affinity between pigment and resin, the processing performance of the product is poor, which will affect the physical and mechanical properties of the product.
3、 Application of titanium dioxide in Papermaking
China has a large population base and a huge consumption of paper. It is the largest paper product production base in the world. In the paper industry, calcium carbonate, talc powder and titanium dioxide are often added as fillers in the paper to improve the physical and mechanical properties of the paper, improve its elasticity, whiteness and gloss, and reduce its moisture absorption and printing penetration. Among many white fillers / pigments, titanium dioxide has high whiteness, good refractive index, high hiding power and stable properties. Under the same addition amount, the opacity of the paper with titanium dioxide is 10 times higher than that of the paper with calcium carbonate or talc as filler. It is one of the important white fillers in the paper industry.
In order to ensure the stability of papermaking process and paper quality, the requirements of the papermaking industry for titanium dioxide are generally: good water dispersion, fine and uniform particles, low iron content, usually only used in high-grade paper and thin paper, or used in combination with other fillers. Different grades and types of paper correspond to different crystal forms of titanium dioxide. For example, adding anatase titanium dioxide to ordinary paper can play the effect of fluorescent brightener. For advanced laminated paper, the paper requires high light resistance and high heat resistance, and the titanium dioxide should be rutile.
Titanium dioxide has stable chemical properties and can be used for paper making under various conditions. Adding TiO2 to functional paper can give it a special effect. This functional paper can be applied to household indoor stickers to absorb harmful gases (formaldehyde, benzene, etc.). Adding titanium dioxide to paper can also give paper sterilization function.
4、 Application of titanium dioxide in ink
Ink is an important material for printing, which is usually composed of resin, filler, pigment and solvent. It is widely used in various printing, such as packaging and decoration, books and periodicals, electronic information circuit board, structure decoration, etc. Titanium dioxide particles are uniform and fine, with high colouring power, strong hiding power and high refractive index. It can be evenly dispersed in the color developing agent, and has excellent physical and chemical stability, making it an essential blending agent in ink products.
The development history of China's ink industry can be traced back to the early 20th century, when relief printing ink was mainly used. In the early 1990s, foreign famous enterprises and domestic large enterprises implemented Sino foreign joint ventures, and the domestic ink industry grew steadily.
In recent years, with the further promotion of China's environmental protection policies, UV curable offset printing ink, UV LED curable offset printing ink, UV screen printing ink and water-based ink have all developed rapidly. Therefore, the demand and application of titanium dioxide for ink are also increasing.
