Hair gel

Hair gel is a hairstyling product that is used to stiffen hair into a particular hairstyle.

History

Analysis of ancient Egyptians mummies has shown that they styled their hair using a fat-based gel. The researchers behind the analysis say that the Egyptians used the product to ensure that their style stayed in place in both life and death. Natalie McCreesh, an archaeological scientist from the KNH Centre for Biomedical Egyptology at the University of Manchester, England, and her colleagues studied hair samples taken from 18 mummies. The oldest is approximately 3,500 years old, but most were excavated from a cemetery in the Dakhleh Oasis in the Western Desert and date from Greco-Roman times, around 2,300 years ago.

The Irish bog body Clonycavan Man, which has been radiocarbon dated to between 392 BC and 201 BC, was found to have been using a hair gel made from pine tree resin imported from Spain or South-west France.

In 1929, the British company Chemico Works invented Brylcreem, which became the market leader among hair styling products in both the U.K. and the U.S. during the following decades.

Hair

Hair is a protein filament that grows from follicles found in the dermis, or skin. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and fine vellus hair. Most common interest in hair is focused on hair growth, hair types and hair care, but hair is also an important biomaterial primarily composed of protein, notably keratin. Attitudes towards hair, such as hairstyles and hair removal, vary widely across different cultures and historical periods, but it is often used to indicate a person's personal beliefs or social position, such as their age, gender, or religion.

Overview

The word "hair" usually refers to two distinct structures:

Gel

A gel (coined by 19th-century Scottish chemist Thomas Graham, by clipping from gelatine) is a solid, jelly-like material that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state. By weight, gels are mostly liquid, yet they behave like solids due to a three-dimensional cross-linked network within the liquid. It is the crosslinking within the fluid that give a gel its structure (hardness) and contribute to the adhesive stick (tack). In this way gels are a dispersion of molecules of a liquid within a solid in which the solid is the continuous phase and the liquid is the discontinuous phase.

Gel: Nonfluid colloidal network or polymer network that is expanded throughout its whole volume by a fluid.

Note 1: A gel has a finite, usually rather small, yield stress.

Note 2: A gel can contain:

Note 3: Corrected from ref., where the definition is via the property identified in Note 1 (above) rather than of the structural characteristics that describe a gel.