CHM361: HOW PIGMENTS AND METAL OXIDES CREATE COLOUR AND COVERAGE IN MAKE UP

[00:00:00][music] [music] >> Hi everyone. My [music] name is Alicia Luschasry and today I'll be introducing the chemistry behind the makeup products that we use everyday. [music] Have you ever wondered what actually gives cosmetics their color and coverage?

[00:00:21]The secret lies in pigments. [music] Specifically, metal oxides are incredibly important in organic compounds used throughout the cosmetic industry.

[00:00:30]>> [music] >> They don't just provide color, they are also a contributor to the opacity, coverage, and the even UV [music] protection of our favorite products.

[00:00:39]Two of the most common examples that you will find on an ingredient [music] list are titanium dioxide and also iron oxide.

[00:00:47]Before we dive into [music] those specific metal oxides, let's look at what pigments actually are.

[00:00:52]By definition, pigments are insoluble [music] particles that impart color.

[00:00:57]Because they are insoluble, they don't dissolve. Instead, they remain finely [music] dispersed within cosmetic formulation like foundation, lipstick, blushes, and eyeshadows. [music] We can generally categorize pigments into two main types. First, organic pigments, which [music] are known for providing bright vivid color. Second is inorganic pigments, which are favored for providing better chemical stability and overall coverage.

[00:01:22]Now, let's look at the heavy hitters among inorganic pigments, which the metal oxides.

[00:01:28]First, we have titanium dioxide. It functions primarily as a white pigment, prized for its high opacity [music] and strong light scattering ability. Next, we have the iron oxide, which come in three primary colors. First, red iron oxide. Second, yellow iron oxide. And lastly, black iron oxide.

[00:01:46]By blending these three primary [music] iron oxides together, we titanium dioxide cosmetic chemists can create the perfect natural skin tone [music] shades for face makeup.

[00:01:57]To wrap things up, let's a little closer at the specific properties and function of titanium dioxide.

[00:02:02]Chemically, [music] it is a white crystalline solid with a high refractive index. It is also highly stable and completely non-toxic, making it incredibly safe for [music] skin application. Because of these distinct properties, titanium dioxide has four main functions in makeup.

[00:02:18]First, [music] it provides whiteness.

[00:02:20]Second, it enhances the coverage of the product. Third, it improves opacity, so it [music] hides blemishes well. And finally, it offers natural UV protection to shield the skin from sunlight.

[00:02:31]Thank you for listening. I'm happy to take any questions you might have.

[00:02:36]>> Next is [music] iron oxides and color creation.

[00:02:40]Iron oxides are important pigments used in makeup products, especially foundation and powders. [music] Different types of iron oxides produce different colors. Red iron oxide [music] creates red and brown shades. Yellow iron oxide creates yellow and warm tones.

[00:02:56]>> [music] >> While black iron oxide creates darker shades. By mixing these pigments in different proportions, manufacturers [music] can produce a wide range of foundation shades suitable for different skin tones.

[00:03:09]>> [music] >> How pigments create color. Pigments create color [music] through their interaction with visible light. When light strikes a pigment, certain wavelengths are absorbed [music] while others are reflected. The reflected wavelengths are what our eyes perceive [music] as color. For example, red iron oxide reflects red wavelengths, which is why it [music] appears red. In contrast, titanium dioxide reflects most of visible light and therefore [music] appears white.

[00:03:39]This principle is essential in cosmetic formulation [music] because it determines the final color of makeup products.

[00:03:48]Move on to the next, chemistry of color.

[00:03:51]The chemistry of color is based on how pigments interact with visible light, which is ranges from approximately 400 to 700 nm.

[00:04:02]Pigments absorb [music] specific wavelengths of light and reflect other.

[00:04:07]The reflected wavelength determine the color [music] observed by the human eye.

[00:04:12]For example, red iron oxide absorbs [music] most wavelengths except red, so red light is reflected and the pigment appears red.

[00:04:22]>> [music] >> Understanding this interaction helps cosmetic chemists design [music] products with the desired color and appearance.

[00:04:32]Next is electronic transitions in metal oxides.

[00:04:36]The colors [music] produced by metal oxides originate from electronic transitions within the atoms. When light is absorbed, electrons gain [music] energy and move to higher energy level.

[00:04:49]Different metal oxides have different electronic structures, causing them to absorb different wavelengths [music] of light. As a result, each metal oxide displays a unique color. This is why transition metal compounds are often [music] strongly colored and widely used as pigment in cosmetic products.

[00:05:10]Understanding these electronic transitions helps explain how metal oxide contribute to both color and coverage in makeup.

[00:05:21]>> Assalamualaikum and hi. My name is Putra Alyssa. For this slide, I'm going to explain how metal oxides, especially titanium dioxide or TiO2, help provide coverage in cosmetic products. Coverage basically refers to how well a product can hide the skin imperfections such as pores, blemishes, redness, and uneven skin tone.

[00:05:39]One of the main reasons titanium dioxide is effective because it can scatter incoming light. When light hits the skin, the titanium dioxide particles spread the light in different directions.

[00:05:50]This reduces the visibility of imperfections, making them less noticeable to the human eyes. Basically, titanium dioxide helps to blur imperfection [music] by scattering light, which is why products containing titanium dioxide can make the skin look smoother and more even.

[00:06:07]Other than that, titanium dioxide reflects light very efficiently due to >> [music] >> its high refractive index. This creates a soft-focus effect that helps blur the appearance of pores and blemishes. It [music] reveals a refined, beautifully balanced complexion and giving you a flawless look without a need for heavy coverage. [music] As we can see from the image, the skin looks more uniform after the product is applied. Therefore, titanium dioxide is not only used as a pigment, but [music] it also improves the overall appearance of the skin through its light- scattering properties. This is why it is commonly used in foundations, face powders, and tinted sunscreens.

[00:06:47]Now, let's look at the chemistry behind the effectiveness of titanium dioxide or TiO2 in cosmetics. Titanium dioxide has a high refractive index, which means it can scatter light very effectively. This helps blur skin imperfections and provides better coverage. It also has strong metal-oxygen bonds, making [music] it chemically stable and durable.

[00:07:10]In addition, titanium dioxide [music] is resistant to heat, light, and oxidation, so cosmetic products remain effective even after long-term use.

[00:07:19]Because of these properties, titanium dioxide is widely used in long-lasting [music] cosmetic formulations such as foundations, sunscreens, and powders.

[00:07:29]For this one, metal oxides offer many advantages in cosmetics. [music] They provide excellent color stability, so the product keeps its original shade over time. They also have high opacity, giving better coverage while remaining low in toxicity, making them safe for [music] cosmetic use. In addition, metal oxides provide UV protection, extend the product's shelf life, and are compatible with many cosmetic formulations, making them widely used in makeup and [music] sunscreen products.

[00:08:00]In conclusion, pigments are responsible for color in makeup, then metal oxides [music] provide both color and coverage.

[00:08:07]Furthermore, titanium dioxide improves opacity and UV protection. Iron oxides also create a variety of cosmetic [music] shades. Last but not least, their unique optical and chemical properties make them essential ingredients in modern cosmetics.

[00:08:25]>> [music] [music]