Viscosity, Density and Concentration Measurements in the Cosmetics Industry

The cosmetic industry requires various analyses for quality control, product development, research and development activities, and compliance with legal requirements; various analytical techniques and instruments are used to perform these analyses in perfumes, creams and other cosmetic products.

Examples include:

• Essence analysis: GCMS • Preservatives (Paraben, Benzoic and Sorbic Acid, Triclosan, Formaldehyde etc.): HPLC, GC, GCMS • Hyaluronic acid: LCMSMS, SEC • SPF (Sun Protection Factor): UV-VIS-NIR • Lead: AAS • Viscosity: Viscometer • Density: Densitometer • Concentration and substance content: Refractometer. This article will discuss viscosity, density and concentration measurements, which are quality control parameters in the cosmetic industry, as well as the characteristics of related instruments and their other applications.

Viscosity Measurements in Cosmetic Products

Viscosity is defined as the resistance of fluids to flow. In the cosmetic industry, viscosity measurements are an important part of quality control both during the production process and in finished products. For example, lip balm must have high viscosity to adhere properly to the skin and provide protection. Conversely, a body spray must have a very low viscosity. The spray can flow freely from the dispenser and be easily absorbed by the body only in this way. The viscosity of a fluid is a parameter that must be measured in pipeline design or when determining equipment in production lines (pump selection, pipe volume/diameter etc.). For this reason, when the reasons why viscosity is important for the overall quality of cosmetic products are considered, viscosity measurements have become the key to successful cosmetic production companies.

Fungilab V-Compact Viscometer

The award-winning V-Compact series from Fungilab, one of the world's leading viscometer manufacturers, stands out as "the world's first rotational viscometer with wireless access." The instrument allows users to access test data and perform multiple application controls in different research areas. With features such as remote access via mobile application, Wi-Fi and Bluetooth functionality, and a unique digital interface, the V-Compact increases user productivity and efficiency; it also provides online remote support in urgent matters.

Measurement Ranges:

• L Series: 15 - 6,000,000 cP • R Series: 25 - 40,000,000 cP • H Series: 200 - 320,000,000 cP

Applications of Viscometers:

• Cosmetic Industry (Creams, lotions, shampoos, detergents, nail polish etc.), • Chemical Industry (Polymers, polyurethane-based samples etc.), • Paint Industry (Paints, ceramic slips) and Printing Industry (Inks), • Food Industry (Milk, buttermilk, yogurt, chocolate, tomato paste, yeast etc.), • Petrochemical Industry (Mineral oils and derivatives, asphalt etc.), • Pharmaceutical and Pharmacy Industry (Quality control tests of suspensions and emulsions), • Textile Industry (Adhesives, paint pastes, rubber, finishing agents etc.).

Density Measurements in Cosmetic Products and Essences

Density measurements are used in the perfume, essence and aroma industries to control blended and/or diluted oils according to desired concentration and customer specifications. Raw materials are controlled in terms of density as well as alcohol, sugar (ºBrix), % solids and many other parameters; for the standardization of the final product, specific gravity determinations must always be performed.

Rudolph Research DDM-2910 Densitometer

• Bubble detection system with scanning video imaging and 10x magnification, • Optional programmable method options, • Ability to work with less than 1 ml of sample, • Touchscreen LCD display, • Measurement Range: 0-3 g/cm³, • Temperature Range: 0°C - 95°C, • Resolution: 0.0001 g/cm³, • Windows 7 operating system and optional 21 CFR Part 11 (User authentication).

Applications of Density Meters

• Food Industry (Density determination in alcoholic beverages), • Universities (Research Laboratories), • Chemical Industry (Chemical sample analysis), • Pharmaceutical Industry (Raw material analysis), • Oil Industry (Petrochemical sample measurements), • Agricultural Industry (Fertilizer and agricultural chemical measurements), • Cosmetic Industry (Essence measurements).

Concentration and Substance Content Determinations in Cosmetic Products

Refraction is the change in direction of light as it passes through different media, and refractive index is the ratio of the speed of light in vacuum to its speed in a substance. Pure liquid substances such as glycerin, ethyl alcohol, acetone and others have their own specific refractive index. Refractive index is one of the physical properties of a substance and is used in the cosmetic industry for quality control measurements of parameters such as refractive index and concentration determination in raw material analyses and in liquid, gel and fluid-type finished products.

Rudolph Research J257 Refractometer

• Measurement Range: 1.26 - 1.72 RI, 0-100 BRIX, • Measurement accuracy: ±0.0001 RI, ±0.1 BRIX, • Temperature Control: 10°C - 100°C, 8 GB memory, • Touchscreen, • Windows 7 operating system and optional 21 CFR Part 11 (User authentication), • Smart Measure (Feedback on sample quality, correct sample loading and cleaning), • Trend Analysis (Graphical display, monitoring of measurement process in repeated long-term measurements).

Applications of Refractometers

• Cosmetic Industry (Concentration and substance content determination), • Universities (Research laboratories), • Food Industry (Sugar industry, olive oil, fruit juice and honey producers. Purity degree determination, water-soluble dry matter determination), • Chemical Industry (Refractive index determination), • Pharmaceutical Industry (Quality control of raw materials and finished products), • Oil Industry (Measuring oil ratios and concentrations), • Agricultural Industry (Determination of solid matter content in liquid materials).   Serhat Çeşme Sales Engineer Ant Teknik Cihazlar Ltd. Şti.