Forefront of Foam Research

Interface Science

In a variety of washing settings, foam gives the user “comfort” and a “feeling of cleaning well”, whereas when foam does not form or disappears quickly, the user senses stress, such as “difficult to wash” or “I do not feel that it is being cleaned”. Therefore, foam plays an important role in comfortable daily cleansing. On the other hand, for rinsing, it is required that all bubbles disappear down the drain.
Kao is working on development of technology to freely and efficiently create comfortable foam, as well as eliminate foam, and exploring new possibilities. When considering formation of foam, the tendency is to think of chemical research, but in addition to that, we have combined a physical perspective by capturing the entire foam as a structure. By investigating from such a wide perspective, we are aiming to understand the essence of foam.
Our research has led to discovery of a phenomenon in which fine bubbles spontaneously take in oil without collapsing*1 . When trying to eliminate distortion in the gas-liquid interface, it was revealed that this is not a simple capillary phenomenon, but actually suction pressure generated by polygonal-shaped bubbles [Fig. 1. (c) (d)] that are densely packed*2 . Discovery of this occurrence greatly contradicts conventional wisdom.
In addition, Kao continues attempts to elucidate the essence of foaming as well as the feeling of foam from both chemical and physical aspects. Findings obtained thus far have been applied to whole body cleaners, such as facial cleansers and shampoos, as well as dishwashing detergents.

  • * 1 The Journal of Physical Chemistry B, 118, 9438 (2014)
  • * 2 The Journal of Physical Chemistry B, 122, 9786 (2018)

Figure 1. State of foam when brought into contact with oil (orange color)

Related Actions and Goals

Kao’s ESG Strategy Kirei Lifestyle Plan

IMPROVED QUALITY OF LIFE

HABITS FOR CLEANLINESS, BEAUTY & HEALTH

Sustainable Development Goals

SDGs GOAL 3:Good Health and Well-being

SDGs GOAL 12:Responsible Consumption and Production

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