Where the plastic is extruded in the manufacturing process, talc's very low hardness produces less abrasion on equipment than harder mineral fillers. When used as a filler in ceramics, talc can improve the firing characteristics of the greenware and the strength of the finished product. Most paints are suspensions of mineral particles in a liquid.
The liquid portion of the paint facilitates application, but after the liquid evaporates, the mineral particles remain on the wall. Talc is used as an extender and filler in paints. The platy shape of talc particles improves the suspension of solids in the can and helps the liquid paint adhere to a wall without sagging. Powdered talc is a very bright white color. This makes talc an excellent filler in paint because it simultaneously serves to whiten and brighten the paint.
Talc's low hardness is valued because it causes less abrasion damage on spray nozzles and other equipment when paint is applied. Most papers are made from a pulp of organic fibers.
This pulp is made from wood, rags, and other organic materials. Finely ground mineral matter is added to the pulp to serve as a filler.
When the pulp is rolled into thin sheets, the mineral matter fills spaces between the pulp fibers, resulting in a paper with a much smoother writing surface. Talc as a mineral filler can improve the opacity, brightness, and whiteness of the paper. Talc also can also improve the paper's ability to absorb ink. Finely ground talc is used as the powder base of many cosmetic products. The tiny platelets of a talc powder readily adhere to the skin but can be washed off easily.
Talc's softness allows it to be applied and removed without causing skin abrasion. Talc also has the ability to absorb oils and perspiration produced by human skin. The ability of talc to absorb moisture, absorb odor, adhere to the skin, serve as a lubricant, and produce an astringent effect in contact with human skin make it an important ingredient in many antiperspirants.
Talc and asbestos occur naturally and may occur in close proximity in some metamorphic rocks. Studies published in the s and s identified health concerns about the use of talc that contains asbestos in some cosmetic products. According to the FDA, "These studies have not conclusively demonstrated such a link, or if such a link existed, what risk factors might be involved.
Talc is added to the asphaltic materials used to make roofing materials to improve their weather resistance. It is also dusted onto the surface of roll roofing and shingles to prevent sticking. A rock known as "soapstone" is a massive variety of talc with varying amounts of other minerals such as micas, chlorite , amphiboles, and pyroxenes. Ground talc is used as a lubricant in applications where high temperatures are involved. It is able to survive at temperatures where oil-based lubricants would be destroyed.
Talc powder is used as a carrier for insecticides and fungicides. It can easily be blown through a nozzle and readily sticks to the leaves and stems of plants. Its softness reduces wear on application equipment. How Does it Form? How is Talc Used? Article by: Hobart M.
Virta, U. Geological Survey, Minerals Yearbook, November Find Other Topics on Geology. Maps Volcanoes World Maps. The products were selected based on various factors including, type of talc-containing cosmetic product, price range, popular products on social media and in advertisements, products marketed to the children, and, if any, third party reports of potential asbestos contamination. For additional information, see:.
FDA release data from a year-long sampling assignment of testing talc-containing cosmetic products for the presence of asbestos. The FDA sampled cosmetic products following reports of asbestos contamination in talc-containing cosmetics.
On February 4, , the FDA opened a public docket and held a public meeting to discuss and obtain scientific data and information on topics related to cosmetic products with talc as an ingredient, specifically, testing methodologies, terminology, and criteria that could be applied to characterize and measure asbestos and other potentially harmful elongate mineral particles EMPs that may be present as contaminants in such products.
Neither the Executive Summary nor any of the presentations at the public meeting by members of the IWGACP, represent proposed or preliminary recommendations or policies of the FDA or any other federal agency. The Executive Summary and related presentations at the public meeting were meant solely to solicit scientific feedback on the issues raised and should not be used for any other purpose. The FDA does not have any recommendations at this time.
Should the FDA decide to develop recommendations with respect to standards or testing methods for asbestos in talc, as a result of the information it received as part of the public meeting and comments to the public docket or otherwise, it would issue draft guidance for public comment. Likewise, the FDA would propose any related regulations through a public notice and comment process. Warning to Consumers. On October 18, , the FDA updated a Safety Alert and issued a Constituent Update warning consumers not to use certain cosmetic products tested positive for asbestos.
Soap manufacturers use talc as a filler, where it enhances the softness and lather of soaps and cuts formulation costs. Talc is used in the pulp, paper and board industry as a filler and to control pitch and stickies which clog machines impacting runnability.
Talc is an effective coating agent in rotogravure and offset papers where it improves runnability and the quality of the finished paper. In certain specialty papers such as colored papers and labels, talc improves quality and productivity.
Talc is an ideal excipient for tablets, a carrier for medicated powders and a glidant and lubricant in tablet production. In pharmaceutical coatings, talc is an excellent anti-tack agent.
It is used in enteric coatings for targeted delivery of drugs. It is used for antiblocking in polyethylene; restores mechanical properties to recycled plastics; and is an ideal nucleating agent in biopolymers and semi-crystalline polymers. Talc is added to wood-plastic composites - increasingly used as a sustainable substitute for lumber in outdoor decking - to improve structural integrity.
Talc is used in seals, hoses, membranes, cables, tires and other mechanical rubber goods to improve processing, permeability, weathering, electrical properties, fire resistance and mechanical properties such as tear.
In tires, high aspect ratio talcs improve the impermeability of inner liners, improving rolling resistance and contributing to better fuel efficiency.
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