Keratotic Plug Disintegrating and Cleansing (KPDC) Technology Combined with Hydrophilic Micropowders
Enables Removal of Keratotic Plugs Deep Within Pores

Keratotic plugs are often noticed on the nose where sebum production is higher, but can be found anywhere on the face, including the cheeks and forehead. In a study^*1 of elementary and junior high school students aged 7 to 13, Kao confirmed that the severity of acne increases as the number of keratotic plugs increases. Moreover, it was observed that skin with more keratotic plugs has a higher ratio of Cutibacterium acnes—bacteria linked to acne—on the skin surface^*2 . Kao also discovered that people in their 40s and 50s have more keratotic plugs on their cheeks than those in their 20s and 30s. These keratotic plugs are a catalytic source of sebum and stratum corneum oxidation, and may cause the skin to appear dull^*3 . Therefore, skincare that targets keratotic plugs is important for people across a wide range of ages.

Keratotic plugs are comprised of mainly solid fats and exfoliated stratum corneum which are layered within the pore in a compact, onion-like structure. This structure makes them difficult to remove by regular facial cleansing alone. In 2017, Kao developed the KPDC Technology using tromethamine to loosen keratotic plugs and cause them to spontaneously disintegrate (video).

Kao has focused its research on blackheads, a major pore-related concern for consumers. To make blackheads less noticeable, it is important to remove keratotic plugs from deep within pores. Kao has therefore been striving to establish a new cleansing technology that can remove keratotic plugs more effectively, based on our KPDC Technology using tromethamine.

When tromethamine comes into contact with keratotic plugs and the solidified oils become softer, the layered structure of the keratotic plug loosens. While the plug is loosened, it is not yet dispersed. Consequently, Kao researchers focused on finding a way to scatter the tromethamine-loosened keratotic plugs to promote its removal from the pores.

After evaluating various ingredients, the research team found that when tromethamine is combined with hydrophilic micropowders with an average particle size of several tens of µm, the swollen keratotic plugs adhere to the hydrophilic micropowders, making them easier to disperse. This is thought to enable the tromethamine to reach further into the pores and remove keratotic plugs embedded within the pores (Figure 2).

To further investigate the cleansing effect, a single-use half-face-cleansing test on 9 Japanese men and women in their 20s and 30s was conducted. A formulation containing tromethamine and hydrophilic micropowders was applied to one half of the face and a formulation without these components to the other. Using 3D images of the nose constructed from photographs taken before and after cleansing, changes in the depth of the pores were analyzed^*7 . With the new technology, many pores exhibited a depth increase of 50 µm or more after cleansing. This change can be attributed to the removal of keratotic plugs lodged deep within the pores. Little change was observed when the new technology was not used (Figure 1). The evaluation also revealed that with the new technology, the appearance of blackheads was less noticeable after cleansing.

These results suggest that the new technology can remove keratotic plugs from deep within pores, improving the appearance of blackheads.

Kao has developed a new cleansing technology that combines tromethamine with hydrophilic micropowders to remove keratotic plugs located deep inside pores. These findings suggest that for consumers troubled by blackheads, daily facial cleansing with products using this technology may help minimize their appearance. Kao will continue to research cleansing technologies tailored to the needs of consumers.

Kao, a Japan-based manufacturer of personal care and household products, cosmetics, and specialty chemicals creates high-value-added products and services that provide care and enrichment for the life of all people and the planet. Through its brands such as Attack laundry detergent, Bioré and Jergens skin care products, Laurier sanitary products, Curél, SENSAI, and MOLTON BROWN cosmetics, and Oribe hair care products, Kao is part of the everyday lives of people across Asia, the Americas, Europe, the Middle East, and Africa. Combined with its chemical business, which contributes to a wide range of industries, Kao generates about 1,630 billion yen in annual sales. Kao employs about 32,600 people worldwide and has more than 130 years of history in innovation. As an enterprise that provides products people use on a daily basis, the Kao Group takes responsibility to actively reduce the environmental footprint of its products throughout the product lifecycle. This is laid out in Kao’s ESG strategy, the Kirei Lifestyle Plan, which launched in 2019.
Please visit the Kao Group website for additional information.