Understanding the characteristics of hair coloring products

Hair coloring product classifications

To find the hair coloring product that is best for you, it is important to first understand the different types of hair coloring products available and their characteristics.

There are many different types of products for coloring hair, and each product is used differently and comes with its own warnings and cautions. Please read the instruction leaflet carefully before using. Always use the product correctly.

 

Difference between hair dyes (quasi-drugs) and hair dyes (cosmetics)

Hair dyes (quasi-drugs) and hair dyes (cosmetics) differ mainly in how they are used and how long the color remains in your hair.

 

How to distinguish hair dyes (quasi-drugs)

Hair dyes (quasi-drugs) and hair dyes (cosmetics) are both available at retail stores. Hair dyes (quasi-drugs) are marked with the phrase quasi-drug (医薬部外品) or active ingredients (有効成分), so these labels are key to distinguish them from other products. Labels with the phrases quasi-drug or active ingredients can generally be found on the sides of the product packages.

 

Hair coloring product classifications

Permanent hair dye [A]

Permanent hair dye is categorized as a quasi-drug. Of the various hair coloring products available, permanent hair dye are best in terms of their ability to color and lighten (bleach) hair. Perform a skin allergy test (patch test) every time before coloring your hair with permanent hair dyes.

 

A-1 Oxidative hair dye (hair color)

Common name(s)
Hair color/Hair dye/Gray hair dye/Fashionable hair dye/Gray and fashionable hair dye/Fashionable coloring

Product type(s)
Cream/Lotion/Liquid/Aerosol/Foam/Powder

Characteristics

  • The color of these products generally lasts for two to three months.
  • They are made up of two agents. The 1st agent (colorant) contains oxidative dyestuff such as p-Phenylenediamine, m-Aminophenol, p-Aminophenol, and Toluene-2,5-diamine, and the 2nd agent (oxidant) contains hydrogen peroxide. These two agents are mixed together when coloring your hair.
  • As oxidative dyestuff may cause allergic reactions due to changes in physical condition, a skin allergy test should be performed every time oxidative hair dye is to be used.

 

A-2 Non-oxidative hair dye

Common name(s)
ohaguro gray hair dye

Product type(s)
Cream

Characteristics

  • Black to dark brown in color, this product is used as a gray hair dye. The color lasts up to one month.
  • It may be used even by those who are prone to allergic reactions from oxidative hair dye.

 

Bleaching agents and dye removers [D]

Bleaching agents and dye removers are categorized as quasi-drugs. Of the various hair coloring products available, bleaching agents are great in terms of their ability to lighten (bleach) hair. Dye removers are great at breaking down any remaining dyestuffs in the hair.

 

D-1 Bleaching agent

Common Name(s)
Hair bleach/Hair lightener

Product type(s)
Liquid/Cream/Foam/Spray/Powder

Characteristics

  • Bleaching agents lighten hair.
  • Products containing persulfates* can significantly lighten hair.
    *Persulfates: ammonium persulfate, potassium persulfate, sodium persulfate

 

D-2 Dye remover

Common Name(s)
Hair bleach

Product type(s)
Cream/Powder

Characteristics

  • Dye removers are used to remove dyestuff left on the hair. However, it is difficult to remove black and dark dyestuff left on the hair or the color deposited by hair manicure.

 

Semi-permanent hair dye [B]

Semi-permanent hair dyes are categorized as cosmetics. They color hair by allowing the pigment to penetrate into the interior of the hair after a single use, or by allowing the pigment to gradually penetrate into the superficial layers of the hair after several consecutive uses.

 

Semi-permanent hair dye (colors hair with single use)

Common Name(s)
Hair manicure

Product type(s)
Aerosol/Gel

Characteristics

  • The color lasts up to two to four weeks.
  • The hair does not experience significant damage, even after repeated use.
  • If it gets on the skin, it may be difficult to remove.

 

Semi-permanent hair dye (colors hair gradually with repeated use)

Common Name(s)
Hair coloring treatment/Hair coloring rinse

Product type(s)
Cream

Characteristics

  • Coloring occurs gradually with repeated use.
  • The hair does not experience significant damage, even after repeated use.

 

Temporary hair dye [C]

Temporary hair dyes are categorized as cosmetics. They change color of your hair temporarily by depositing a colorant on the surface of the hair.

 

Temporary hair dye (color deposited on hair can be shampooed out)

Common Name(s)
Hair mascara/Hair coloring spray/Hair marker/Hair foundation

Product type(s)
Mascara/Aerosol/Powder/Marker

Characteristics

  • Easy to use, just apply.
  • washed off when shampooed