Leather sewing machine

The position of the needle as it enters and exits the leather is fundamental to achieving secure stitches. Ideally, you should hold the leather firmly but not excessively tight, as this can distort the material. When inserting the needle, aim to enter the leather at a 90-degree angle to maintain consistent stitch depth. This angle not only ensures a cleaner penetration but also helps create uniform spacing between stitches.

3. Build Quality The materials used in manufacturing an auto sewing machine can significantly affect its price. Machines made from high-quality metals typically offer greater stability and longevity compared to those made predominantly from plastic.

When choosing an automotive sewing machine, it's important to consider factors such as the size of the workspace, the number of available stitches, and the type of materials you'll be working with. It's also a good idea to invest in a machine that offers features like automatic thread cutting and speed control to streamline the sewing process and improve efficiency.

Animal studies have shown that, when consumed as a food additive, titanium dioxide can induce intestinal inflammation.

Titanium dioxide comes in the form of a white powder and is sometimes used in cosmetics to adjust a color to a lighter shade. This is also why it can produce a white cast.

A few non-dietary studies have reported adverse effects in the gastrointestinal tract of laboratory animals given food-grade TiO₂. However, these same effects were not seen when the same or higher doses of food-grade TiO₂ were administered in the animals' diet. Dietary studies best reflect how humans are exposed to TiO₂ from food. Thus, the Food Directorate placed the most emphasis on the results of these studies in the state of the science report.

In addition to controlling the reaction conditions, it is also important to carefully monitor the precipitation process to ensure that the desired precipitation percentage is achieved. This can be done through various analytical techniques, such as X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, which can provide valuable insights into the particle size distribution, crystallinity, and purity of the titanium dioxide product.

Specific gravity:

Water solubles, %

Having thus described the origin and uses of the pigment, we now come to the question, what is lithopone? It is, in short, a chemical compound usually consisting of 30.5 per cent zinc sulphide, 1.5 per cent zinc oxide and 68 per cent barium sulphate, but these proportions vary slightly in the different makes. Lithopone of this composition is sold as the highest grade, either as red seal or green seal, as it best suits the idea of the manufacturer. Many manufacturers, especially in Europe, sell and also export other brands under other seals, containing 24, 20, 18 and as little as 12 per cent of zinc sulphide with very small percentages of zinc oxide, the balance being usually barium sulphate, but sometimes certain portions of China clay or gypsum (calcium sulphate) or whiting (calcium carbonate). Such brands are not a chemical compound, but mechanical mixtures of the chemically compounded lithopone and the admixtures referred to.

Titanium dioxide can amplify and brighten white opacity because of its exceptional light-scattering properties. In food and drugs, these properties help to define colors clearly and can prevent products from UV degradation. 

In a 2020 study published in the Journal of Trace Elements in Medicine and Biology, researchers conducted an in vitro experiment to analyze the effects of TiO2 nanoparticles on a human neuroblastoma (SH-SY5Y) cell line. The scientists evaluated “reactive oxygen species (ROS) generation, apoptosis, cellular antioxidant response, endoplasmic reticulum stress and autophagy.” The results showed that exposure to the nanoparticles “induced ROS generation in a dose dependent manner, with values reaching up to 10 fold those of controls. Nrf2 nuclear localization and autophagy also increased in a dose dependent manner. Apoptosis increased by 4- to 10-fold compared to the control group, depending on the dose employed.” 

It's also worth noting that even prior to the EU decision, France had already outlawed titanium dioxide in food back in January 2020.

Water solubles, %

Although barium sulfate is almost completely inert, zinc sulfide degrades upon exposure to UV light, leading to darkening of the pigment. The severity of this UV reaction is dependent on a combination of two factors; how much zinc sulfide makes up the pigments formulation, and its total accumulated UV exposure. Depending on these factors Lithopone B301, Lithopone B311 powder itself may vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant might be used, like small amount of cobalt salts, which would be added to the formulation. This process creates cobalt-doped zinc sulfide. The cobalt salts help to stabilize zinc sulfide so it will not have as severe a reaction to UV exposure.

TiO2 is a white pigment that is commonly used in the production of paints, plastics, and paper. It is known for its brightness, opacity, and durability, making it an ideal choice for products that require a high level of whiteness and coverage. TiO2 is also used in sunscreen lotions and cosmetics to provide protection against harmful UV rays. In addition, TiO2 is used in the food industry as a food additive to enhance the appearance of products such as candies and confectionery.

When manufacturers add titanium dioxide to foods and other ingestible products, it’s typically referred to as E171, which relates to food-grade purity.