It’s true that titanium dioxide does not rank as high for UVA protection as zinc oxide, it ends up being a small difference (think about it like being 10 years old versus 10 years and 3 months old). This is not easily understood in terms of other factors affecting how sunscreen actives perform (such as the base formula), so many, including some dermatologists, assume that zinc oxide is superior to titanium dioxide for UVA protection. When carefully formulated, titanium dioxide provides excellent UVA protection. Its UVA protection peak is lower than that of zinc oxide, but both continue to provide protection throughout the UVA range for the same amount of time.
A great number of other brands with fancy names have gone out of the German market, because of some defects in the processes of manufacture. The English exporters, as a rule, offer three or four grades of lithopone, the lowest priced consisting of about 12 per cent zinc sulphide, the best varying between 30 and 32 per cent zinc sulphide. A white pigment of this composition containing more than 32 per cent zinc sulphide does not work well in oil as a paint, although in the oilcloth and shade cloth industries an article containing as high as 45 per cent zinc sulphide has been used apparently with success. Carefully prepared lithopone, containing 30 to 32 per cent sulphide of zinc with not over 1.5 per cent zinc oxide, the balance being barium sulphate, is a white powder almost equal to the best grades of French process zinc oxide in whiteness and holds a medium position in specific gravity between white lead and zinc oxide. Its oil absorption is also fairly well in the middle between the two white pigments mentioned, lead carbonate requiring 9 per cent of oil, zinc oxide on an average 17 per cent and lithopone 13 per cent to form a stiff paste. There is one advantage in the manipulation of lithopone in oil over both white lead and zinc oxide, it is more readily mis-cible than either of these, for some purposes requiring no mill grinding at all, simply thorough mixing with the oil. However, when lithopone has not been furnaced up to the required time, it will require a much greater percentage of oil for grinding and more thinners for spreading than the normal pigment. Pigment of that character is not well adapted for use in the manufacture of paints, as it lacks in body and color resisting properties and does not work well under the brush. In those industries, where the paint can be applied with machinery, as in shade cloth making, etc., it appears to be preferred, because of these very defects. As this sort of lithopone, ground in linseed oil in paste form, is thinned for application to the cloth with benzine only, and on account of its greater tendency to thicken, requires more of this comparatively cheap thinning medium, it is preferred by most of the manufacturers of machine painted shade cloth. Another point considered by them is that it does not require as much coloring matter to tint the white paste to the required standard depth as would be the case if the lithopone were of the standard required for the making of paint or enamels. On the other hand, the lithopone preferred by the shade cloth trade would prove a failure in the manufacture of oil paints and much more so, when used as a pigment in the so-called enamel or varnish paints. Every paint manufacturer knows, or should know, that a pigment containing hygroscopic moisture does not work well with oil and driers in a paint and that with varnish especially it is very susceptible to livering on standing and to becoming puffed to such an extent as to make it unworkable under the brush. While the process of making lithopone is not very difficult or complicated, the success of obtaining a first class product depends to a great extent on the purity of the material used. Foreign substances in these are readily eliminated by careful manipulation, which, however, requires thorough knowledge and great care, as otherwise the result will be a failure, rendering a product of bad color and lack of covering power.
Titanium dioxide morning tips
1 Rutile type titanium dioxide
As of the close of last Friday, the average price of the sulfuric acid rutile titanium dioxide market assessment is 15683 yuan/ton, the domestic market mainstream negotiation reference 15200-16200 yuan/ton, the mainstream factory in hand orders are okay, coupled with the upstream raw materials expected to be strong, the new single offer to maintain a strong state, the market low price supply reduction.
According to the feedback of manufacturers, the recent mainstream factory new single price, the overall market transaction focus has moved up. On the demand side, the terminal in August is still the off-season, many downstream last month to replenish just need inventory, the current batch purchase intention is limited, the market turnover is low. From the supply side, the mainstream manufacturers still have production reduction or maintenance adjustment inventory in the off-season, and the supply side output is low. Some plastics and papermaking related downstream feedback some models have high prices. Recent titanium dioxide raw material price upward support has been enhanced, comprehensive market factors, the current titanium dioxide market into the stable price state after rising.
2 Anatase titanium dioxide
As of the close of last Friday, the average price of the domestic anatene titanium dioxide market was estimated at 13,000 yuan/ton, and the mainstream reference range for negotiation was mostly centered on 12,500-13,500 yuan/ton. The actual direct selling link price is still more reference in 13,000 yuan/ton. Some lower-priced producers offer even lower prices. On the demand side, because the current price is still relatively low, some downstream bargain purchasing. On the supply side, some manufacturers operate at low load or have maintenance plans. The comprehensive market supply and demand situation and the trend of raw material prices rise, the current market actual transaction price is stable and strong, some manufacturers of titanium diox
One such technology is the use of fluidized bed reactors, which allow for more efficient heat and mass transfer, resulting in higher production rates and lower energy consumption One such technology is the use of fluidized bed reactors, which allow for more efficient heat and mass transfer, resulting in higher production rates and lower energy consumption
