The process described is seen to consist of preparing separate solutions of readily-soluble salts of zinc and barium together with a third salt, which will further the reaction and at the same time upon uniting the solutions produce by one set of combinations lithopone and a marketable byproduct. This process, moreover, insures the greatest purity of the substances produced and avoids the expense attendant upon more difficult methods in common use. Thisis particularly true with respect to the manufacture of various grades of lithopone, since by properly calculating the amounts of the ingredients used, as above illustrated, any desired quality of lithopone may be produced without mixing additional substances to increase or decrease the percentage of zinc sulfid. The entire product, too, is an absolutely uniform mixture when prepared in accordance with my process.
titanium oxide and 2 per cent' sulphuric acidand 63 per cent water, are slowly added to a solution containing 1050 pounds of barium sulphide, held in a large cylindrical tank, provided with a rotary agitation :capable of producing rapid agitation. The mass isthus v rapidly agitated, and the 2 per cent of sulphuric acid contained in the titanium acid cake reacts with a small portion of the barium sulphide. This reaction may be represented by the following equation TiO H 80 The free sulphuric acid of the titanium acid cake is neutralized by thebarium sul-' phide solution, forming barium sulphate and hydrogen sulphide, as indicated by the above equation. As the sulphuric acid is present only in a small percentage, the major porltiion of the barium sulphide remains as suc very fine colloidal suspension. The barium sulphate produced is also very fine, and the presence of this. very fine barium sulphate in suspension, and also of the very fine colloidal titanium oxide, is believed to be the explanation of the great improvement in the properties of the finished lithopone.
A study published in the Journal of Agricultural and Food Chemistry in 2019 sought to examine the effects of titanium dioxide on intestinal inflammation. Researchers did this by feeding rats titanium dioxide nanoparticles and found that, after the course of two to three months, the animals had lower body weights and induced intestinal inflammation. The researchers also found the nanoparticles altered gut microbiota composition and aggravated chronic colitis. The rats also experienced reduced populations of CD4+T cells (which are cells that help organize immune responses by prompting other immune cells to fight infection), regulatory T cells, and white blood cells in mesenteric lymph nodes. The researchers wrote: “Dietary TiO2 nanoparticles could interfere with the balance of the immune system and dynamic of gut microbiome, which may result in low-grade intestinal inflammation and aggravated immunological response to external stimulus, thus introducing potential health risk.”
Used for coloring paint, ink, rubber, etc. Inorganic white pigments are widely used as white pigments in plastics such as polyolefin, vinyl resin, ABS resin, polystyrene, polycarbonate, nylon and polyformaldehyde, as well as paints and inks. It is less effective in polyurethane and amino resins, and less suitable in fluoroplastics. It is also used for coloring rubber products, papermaking, varnished cloth, oilcloth, leather, watercolor paints, paper, enamel, etc. Used as an adhesive in the production of electric beads.
Lithopone is an inorganic white pigment, obtained from co-precipitation of Zinc sulfide (ZnS) and Barium sulfate (BaSO4). Titanium Dioxide (TiO2) has replaced Lithopone as a white pigment in majority applications as TiO2 is more durable. However, it is much cheaper than TiO2 and has advantages such as low binder requirement and good dispensability. As a white pigment, it can improve the substrate's weather resistance, and improve the fungicidal properties of paint formulations. Some of the major applications of Lithopone include manufacturing of paint pigments, plastic & rubber products, paper, printing inks, cosmetics, and leather & linoleum products. It is commercially available under names such as pigment white 5, Barium zinc sulfate sulfide, Becton White, C.I. 77115, Charlton White, Enamel White, and Zincolith. On the basis of content of ZnS, Lithopone is available at 28%-30% Lithopone and 60% Lithopone.
The gastrointestinal tract is a complex barrier/exchange system, and is the most important route by which macromolecules can enter the body. The main absorption takes place through villi and microvilli of the epithelium of the small and large intestines, which have an overall surface of about 200 m2. Already in 1922, it was recognized by Kumagai, that particles can translocate from the lumen of the intestinal tract via aggregation of intestinal lymphatic tissue (Peyer’s patch, containing M-cells (phagocytic enterocytes)). Uptake can also occur via the normal intestinal enterocytes. Solid particles, once in the sub-mucosal tissue, are able to enter both the lymphatic and blood circulation.
