Beauty and personal care currently represent 9.0% of the health and wellness industry, with global revenues estimated to reach $557.2 billion in 2023 and growing at a 7.7% CAGR through 2030.¹⁰

Both glass and ceramics find use in this sector for their unique functional and aesthetic properties (see the article “Ceramic materials in cosmetic and toiletry products” in this issue). For example, borosilicate glass has long been used as a bulking agent in the form of flakes, either uncoated, silicone-coated, or combined with various pigments.

Another common glass form is represented by microspheres, that is, microscopic rounded particles with diameter ranging from 1 micron to 1,000 microns. They are added to creams, lipsticks, skin care lotions, foundations, and eye shadows to improve their rheology and create a soft and silky texture. In addition, they blend well with other ingredients, contributing to a natural look, and have a slight abrasiveness suitable for exfoliation and scrubbing. Plus, they scatter light, making small skin imperfections and wrinkles less visible. Hollow microspheres are less transparent than the solid ones, but they are preferred when there is also a need to enhance emulsification of oil or fat-based formulations.

A common method for producing glass microspheres is by ejecting very fine glass powder through a gas flame; as the viscosity of the glass decreases, surface tension causes the particles to become rounded. Hollow microspheres are obtained with a similar process, but a blowing agent such as sodium sulfate or sodium silicate is added to the glass powder.

Glass microspheres for cosmetics and personal care can be manufactured from different types of glass, including soda–lime–silica formulations, borosilicate, and bioactive glass. Prizmalite Industries (New York, N.Y.), for example, produces highly transparent soda–lime–silica microspheres with an average diameter of between 3 microns and 6 microns and very tight particle distribution. They are very effective for disguising wrinkles and skin imperfections and for reducing gloss in foundations and eye shadows.

“Most materials are composed of particles of irregular or uneven forms [crystalline structures]. These uneven ‘surfaces’ reflect light as diffuse reflection, where the reflected light bounces off randomly and in all directions,” the Prizmalite website states.³⁸ In contrast, glass has a smooth surface, so light only transmits or reflects in a consistent direction and angle. Thus, it “fools” the eye and “disguises any underlying wrinkles, discoloration, or uneven pigmentation,” according to the Prizmalite website.

By comparison, 3M (St. Paul, Minn.) sells solid microspheres made from amorphous magnesium silicate with an average diameter of 5 microns. These white microspheres are ideal for producing creams as they create low friction, are easily dispersible, allow for high solid loading, and can be surface treated. Another example is Potters Industries (Malverne, Pa.), which supplies calcium aluminum borosilicate microspheres with mean diameters of 11 microns and high chemical resistance with low alkali leaching.

The microsphere market is projected to reach $7.3 billion in 2023 and grow at a CAGR of 9.1%.³⁹ The cosmetics industry will be one of the most significant segments driving industry growth in the U.S. because this country is the largest beauty market worldwide, with the presence of many major cosmetic brands.

Bioactive glass also finds application in many cosmetics and personal care products, including anti-aging creams, antibacterial soaps, make-up, deodorants, skin care products, sunscreens, and nail polishes. Bioactive glass can be used for various functions, such as antimicrobial agents, anti-oxidative components, skin-soothing ingredients, anti-wrinkle aids, anti-odor additives, protective materials against high temperatures and ultraviolet radiation, and nail strengthener.

Schott (Mainz, Germany), a world leader in specialty glass, offers calcium sodium phosphosilicated bioactive glass powder produced in dedicated glass melting tanks and grinding facilities to ensure the high purity requested for cosmetic applications. The company also offers a mica-based version formulated to improve dispersion and enhance aesthetics.

Bioactive glass is also an ingredient in some toothpaste brands. In 2021, BioMin Technologies (Stoke-on-Trent, U.K.) received FDA clearance to sell its bioactive glass toothpaste in the U.S., although it had been available in other countries for more than a decade.

During brushing, BioMin’s bioactive-glass-based toothpaste dissolves in saliva and forms fluoroapatite, an acid-resistant mineral layer that coats the tooth surface, strengthening the enamel and reducing tooth sensitivity. The company also sells an alternate version in which chlorine replaces fluorine. This product generates a hydroxyapatite layer very quickly, but the film is less resistant to acids.

Spherical face-massaging tools made from borosilicate glass are becoming quite popular (Figure 7). Borosilicate ensures resistance to a wide range of temperatures, which allows the tools to be cooled in the refrigerator or immersed in hot water. Thanks to their perfectly rounded shape, these tools can be easily rolled on the skin. They are marketed as being able to improve blood circulation; remove fine lines, eye bags, and dark circles; soothe the skin; shrink pores; and repair sunburns.

Glass cups are also sometimes used in cupping therapy, though durable silicone or plastic cups are more common because they can more easily be moved in stroking sweeps across the body.

Glass is one of the most important materials for packaging of cosmetics and personal care products. In fact, the glass cosmetic packaging market was valued at $5.2 billion in 2022,⁴⁰ of which $3.5 billion is accounted for by glass bottles (67.3% of the total),⁴¹ and this market is projected to grow at a 4.4% CAGR through 2032.

With its inertness, lack of porosity, and impermeability, glass ensures formulation stability. It can be manufactured in gloss or matte finish and in clear, blue, green, amber, and other colors. Additionally, it can be easily molded in a variety of shapes and sizes, such as perfume bottles, jars for creams, nail polish bottles, and painted containers. Containers offer many options in terms of lids and closures (plastic, wood, cork, ceramic, and metal) allowing for the creation of articles that range from being relatively inexpensive to high-end luxury products.

Ceramics also have some relevant applications in the beauty and personal care industry, such as serving as packaging material. One of the most captivating features of ceramics is that they can be made with different compositions (porcelain, earthenware, composites), formed into very complex shapes, and painted or glazed to achieve a multitude of colors. After they are emptied from their content, ceramic containers can be recycled as art or decorative objects or for other uses (e.g., office supply organizers, candle holders, pots for plants, candy boxes).

In addition to their aesthetic qualities, ceramics have a number of functional properties that come in handy in a range of applications, such as: bowls and spatulas for preparing beauty recipes (e.g., facial masks and skin creams); cleaning tools for make-up brushes; anti-slip soap dishes; make-up organizers; dispensers and closures for bottles and jars; stylish nail files for manicures and pedicures; foot files for softening rough and dry skin; wear-resistant nail drill bits for shaping natural and acrylic nail tops; porcelain heating elements for hair straightening irons; and heated round hair brushes to reduce static electricity.

Ceramics also find application in some ethnic cosmetic practices. Gua sha, for example, is a Chinese traditional healing technique that uses ceramic sculpting tools to massage and slightly scrape the skin with the purpose of improving blood flow and lymphatic drainage. Gua sha can be applied to a person’s face to remove surface impurities and wrinkles and achieve a better skin complexion, or to other parts of the body to relieve pain and stiffness.

Clay facial masks are also a popular product in the cosmetic and personal care industry, with silica, alumina, potassium oxide, and calcium oxide being common components in these masks.⁴²

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• Factors driving demand in the health and wellness industry
• Sport, fitness, and recreational activities
• Traditional, complementary, preventive, and personalized medicine
• Wellness tourism
• Nutrition and weight management
• Beauty and personal care
• Wellness real estate
• Mental and spiritual wellbeing
• Workplace wellness