Titanium dioxide (CI 77891)

Origin and Production

Sulfate Process

• This older method starts with mixing ilmenite (FeTiO3) with sulfuric acid.
• Iron(II) sulfate, a by-product, is crystallized and filtered.
• The remaining titanium sulfate is hydrolyzed to form hydrated titanium dioxide, which is then heated to form titanium dioxide crystals, either anatase or rutile, depending on the temperature.

Chloride Process

• A more modern and efficient method, the chloride process requires high-grade rutile ore.
• Titanium dioxide is reduced with carbon and then chlorinated.
• Liquid titanium tetrachloride (TiCl4) is distilled and oxidized in a pure oxygen flame or plasma at high temperatures to revert to titanium dioxide.
• This process is known for producing a purer and higher quality product.

Production of Nanostructured Titanium Dioxide

• It involves evaporating TiCl4 and mixing it with air and hydrogen.
• The mixture is heated at high temperatures, converting TiCl4 to titanium dioxide.
• The resulting titanium dioxide consists of nanoparticles that are invisible to the naked eye and maintain transparency when suspended in liquid or coated onto glass.

The particle size of titanium dioxide

• Optimal Light Scattering. The larger particle size of titanium dioxide in pigments is purposeful. It provides optimal visible light scattering, crucial for achieving high opacity and brightness. These characteristics are particularly important in pigmentation applications, where strong coverage and a bright, vivid color are desired.
• Purity and Quality Considerations. The quality of titanium dioxide varies based on its processing and the raw materials. High purity is crucial, especially in cosmetics and pharmaceuticals, to avoid undesirable side effects from impurities.
• Special Processing for Specific Uses. In some applications, titanium dioxide undergoes further processing. It might be coated with silica or alumina to enhance dispersion in particular mediums. In cosmetics, achieving the right particle size and shape is key for effective skin coverage and reducing the risk of skin irritation.

Food Products and Sweets

• Candies, especially white or brightly colored ones.
• Icings on cakes, cookies, and donuts.
• Chewing gum for its white color.
• Pre-packaged snacks like chips and crackers for color stabilization.
• Dairy products like yogurt, cheese, and dairy-based coffee creamers.

Personal Care Products and Cosmetics

• Toothpaste, for its bright white color.
• Physical sunscreens reflect UV rays.

Other Household Items

• Paints to provide a bright white base.
• Plastic items like utensils and furniture for coloration and durability.
• High-quality paper for a smoother and whiter appearance.

• Enhanced Longevity. Titanium dioxide increases the reflectivity of pigments, leading to longer-lasting color stability. This helps prevent the pigment from shifting into undesirable hues, especially lip and eyebrow pigments.
• Stable and Bright Colors. Pigments with titanium dioxide are reported to produce more stable, vivid results. Aside from the white provided by titanium dioxide, the pigment's colors tend to remain stable in the skin, ensuring consistent color over time. This particularly benefits eyeliner and lip coloring, where brighter, enduring results are desired.
• Predictable Fading. Pigments containing titanium dioxide fade more predictably and evenly. As they lighten, the ratio of white titanium dioxide molecules to colored molecules changes, leading to a clear and consistent fading process. This gradual lightening is due to the extended presence of titanium dioxide in the skin.
• High Refractive Index. The high refractive index of titanium dioxide scatters light effectively, making the pigment appear brighter and more opaque. This allows for achieving true-to-tone color in fewer passes and prevents the pigment from appearing dull or bleached.
• Chemical Stability. Chemically, titanium dioxide is a stable compound that doesn't react easily with other elements, preserving the pigment's original color and affecting its metabolization in the skin. It demonstrates low solubility in water, as seen when pigments containing titanium dioxide separate and settle when poured into water.
• Temperature Influence. Titanium dioxide can lend a cool undertone to the pigment, which is crucial when selecting pigments for a specific final appearance in semi-permanent makeup.

• Longer Retention in Skin. Titanium dioxide persists in the dermal layers, unlike other colorants that fade over time. Its long-term retention can be a concern, especially when pigment changes are desired.
• Resistance to Fading. The physical and chemical properties of titanium dioxide make it less susceptible to the mechanisms that typically cause pigments to fade, such as UV radiation and the body's immune response. Its larger particle size and high refractive index make it more visible and harder to break down.
• Challenges in Removal. Titanium dioxide is resistant to conventional laser removal methods. Its high refractive index makes it less absorbent to laser treatments, which can cause pigments containing titanium dioxide to darken instead of being eliminated.
• Carcinogenic Concerns. While titanium dioxide is classified as a possible carcinogen (Group 2B) by the IARC, this primarily concerns inhalation in industrial settings. However, the risks associated with its use in semi-permanent makeup pigments, particularly through inhalation during application, should not be overlooked.
• Concentration in Lip Pigments. A high titanium dioxide concentration in lip pigments can benefit lighter or nude effects but may not be optimal for darker skin types. Dermatologists caution against its use in high concentrations on darker skin, as it may lead to undesirable healing outcomes, like lips healing to a black color.
• Not Ideal for Dark Skin. Titanium dioxide is often less suitable for darker skin types (Fitzpatrick types 5 and 6). The pigment's properties can result in unexpected and unwanted color changes during healing.

• Purpose of Titanium Dioxide. Titanium dioxide is primarily used to lighten the tone of pigments. Brow pigmentation aims to match or enhance the natural brow color rather than lighten it. Adding titanium dioxide can "dilute" the intended color, making the result appear lighter than desired.
• Healing Concerns. After the pigment application, as the skin undergoes its natural healing process, the organic components of the pigment fade or metabolize. This leaves the inorganic titanium dioxide particles behind, which can lead to a patchy and uneven light gray shade in the brows.
• Undesirable Appearance. The remaining titanium dioxide can give the eyebrows a "light dirty grayish" look. It resembles a black color veiled with a semi-transparent film, resembling soap residue. This effect can create an uneven appearance, with some areas appearing darker and more prominent.
• Professional Preference. Due to these reasons, many brow pigmentation professionals prefer not to use pigments containing titanium dioxide. They opt for formulations that align more closely with the natural brow color and heal more predictably, avoiding the potential patchiness and lightening effect caused by titanium dioxide.

• Nanoparticle Size. In its nanoparticle form, titanium dioxide particles typically range from 10 to 100 nanometers. Nanoparticles are so small that they might interact with biological tissues uniquely, raising concerns about their safety.
• Pigment Particle Size. In contrast, the titanium dioxide particles used in semi-permanent makeup pigments are considerably larger, usually around 200-250 nanometers and sometimes up to 400-500 nanometers. This significant size difference changes how these particles interact with the body.
• Safety Concerns. The concerns about the carcinogenicity of titanium dioxide mostly pertain to its nanoparticle form. These smaller particles have different properties and potential health risks compared to the larger particles used in pigments.
• Ongoing Research. As of January 2022, research on the safety of titanium dioxide in various forms is ongoing. This includes investigations into its potential links to diseases like inflammatory bowel disease and colorectal cancer. However, these concerns have not been conclusively connected to the larger particle forms used in semi-permanent makeup.
• Marketing and Misinformation. Marketing that labels titanium dioxide as categorically "carcinogenic" may not accurately represent the current scientific understanding. It's essential to differentiate between the potential risks associated with nanoparticles and the larger particles used in pigments.

• Chemical Removal System. The most effective approach for removing titanium dioxide involves using various acids and salts. These substances are designed to break down the granulated pigment particles in the skin, facilitating their removal.
• Multiple Sessions Required. The removal process typically requires multiple sessions to achieve optimal results. The number of treatments needed varies depending on several factors, including the intensity of the makeup, the type of pigment used, and the depth of its application in the skin.
• Post-Removal Reactions. After a removal session, it's common to observe some skin bleaching. This reaction occurs due to the release of gas when the pigment is heated during the removal process.
• Frequency of Sessions. Each removal session can be repeated after a minimum interval of six weeks. This interval allows the skin to recover and respond adequately to subsequent treatments.
• Effectiveness Across Color Spectrum. One of the significant advantages of chemical removal methods is their effectiveness across a broader range of colors. Unlike laser removal, which is primarily effective on black, red, and gray pigments, chemical removers can effectively tackle very dark pigmentation, including those containing titanium dioxide.
• Limitations of Laser Removal. Traditional laser removal techniques have limited effectiveness on pigments containing titanium dioxide. This is due to the unique properties of titanium dioxide, which make it resistant to absorption by laser treatments.

• Longevity in the Body. Titanium dioxide is known for its longer retention in the body than other PMU substances. This characteristic is not unique to titanium dioxide; other chemicals and colorants used in PMU share similar properties.
• Critical Approach to Claims. It's essential to maintain a critical perspective when encountering claims about pigments, whether pro or anti-titanium dioxide. Both sides of the argument may have financial incentives influencing their stance.
• Pro-Titanium Dioxide Argument. Advocates of titanium dioxide often highlight its benefits, such as brighter and more vibrant results. They might downplay the negatives and criticize other colorants.
• Anti-Titanium Dioxide Argument. Opponents of titanium dioxide may label it a lower quality or potentially harmful option, sometimes overstating claims about its carcinogenicity. This perspective often stems from the smaller nanoparticle form of titanium dioxide, which differs from the larger particles used in PMU pigments.
• Balanced Perspective. Titanium dioxide is not the sole problematic element in PMU pigments. Other substances, including carbon and metals, can pose risks in certain forms or sizes. While titanium dioxide does stay longer in the body, it's not inherently harmful in the context of PMU. Both artists and clients should know its longevity and plan accordingly for touch-ups or removal.
• Informed Decision-Making. Understanding the properties and implications of titanium dioxide in PMU allows artists and clients to make informed decisions. It's crucial to weigh its use's benefits and potential drawbacks in pigmentation work.

• Longevity. It enhances the durability of pigments, ensuring the color remains vibrant over time.
• Stable, Brighter Colors. It contributes to the stability and brightness of colors in pigments.
• Predictable Fading- The gradual fading process with titanium dioxide is more uniform, allowing consistent color change over time.

• Long Retention in the Skin. Titanium dioxide persists longer in the skin than other colorants, which may be a concern during removal processes.
• Resistance to Laser Removal. Its resistance to conventional laser removal techniques can pose challenges in pigment removal.
• Health Concerns. There are semantic debates regarding its health effects, with some claims labeling it as carcinogenic. These concerns primarily arise from its use in nanoparticle form, which differs from the larger particles used in pigments.