Patent of the week- Hair dye composition comprising acid dyes
From Ancient Egypt to modern-day America, hair color has been a consistent beauty trend. Our methods and options have changed dramatically through history, but the interest in the potential of hair color remains unchanged. Ancient Egyptians were some of the first known people to use hair dye. Like many great modern inventions, hair color as we now know it was invented by accident. The dyeing of hair is an ancient art that involves treatment of the hair with various chemical compounds pulled from different plant extracts to modify the color of their hair.
Present day hair coloring, or hair dyeing, is the practice of changing the hair color with artificially developed hair dyes but the purpose of hair coloring remains the same.People have continued to color their hair throughout history, but thankfully dyeing techniques have become a bit more pleasant because of the constant improvements being scientifically made in the composition of hair dyes and one of such invention is the hair dye composition comprising acid dyes patented by Kao Corporation on 1st August 2000 bearing patent number, US6096099A.
Prior to this invention, acid hair dye compositions comprising an acid dye and various kinds of organic solvents have been good in penetrability into hair, but insufficient in hair-dyeing ability and fastness to shampoo. Thus, the present invention provides a hair dye composition comprising benzyloxyethanol and/or benzyl alcohol, propylene carbonate and an acid dye, and having a pH of 2.0 to 6.0 which improves the hair dye’s fastness to the shampoo and improves the extent of durability. In order to use the hair dye composition, it is only necessary to apply a proper amount of the hair dye composition to the hair to extract best results.