R&D Information

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-Inside Lock- -Inside Lock-

The secret lay inside the hair itself. The secret lay inside the hair itself. The secret lay inside the hair itself.

Perpetual challenge facing
hair styling agents
Natural finish+ Holding power that keeps style
Holding power that all day long keeps style all day long

Gel, wax, foam… there are many different types of styling agents.
However, all of them add on substances on outside of the hair to create styling.
Therefore, it is very difficult to achieve a styling that holds while leaving a natural luster like untreated hair.
It has been the perpetual challenge for hair styling agents to achieve both the natural finish and powerful hold.

The hair styling technology that had previously existed…

Used methods of styling
on the outside Conventional hair-styling technology
(acting on hair externally)

Hair appearance/Hair cross-section

Applying hair-setting polymers or wax onto hair externally,
Setting or fixing together hair in order to keep the style that was created.

The big enemy
for keeping hold of the created styling is

『Humidity』

Why? Because this is how hair behaves

  • 1Internal condition of hair 1Internal condition of hair
  • 2Internal condition of hair 2Internal condition of hair
  • 3 3

Challenge faced by
conventional styling technology

If the volume content of styling agent is increased to strengthen the hold on
style The luster that inevitably accompanies styling agent increases also.

Natural finish
cannot be achieved…

So, Mandom
thought outside the box!

If we could lock the movement of hair by
penetrating ingredients into hair,
Then can’t we achieve both
Natural finish, and Holding power that can stand up to humidity?

So, Mandom thought outside the box! So, Mandom thought outside the box!

Styling from inside hair insidelock technology Styling from inside hair insidelock technology

Inside Lock technology is a different approach from before, working from inside the hair!!

How Inside Lock technology works

Ionic bonding that can withstand humidity
is formed inside of the hair

Image of internal condition of hair with
ionic bonding

Proteins inside hair that create movement of hair are bonded using ionic bonding that can withstand humidity.

Image of bonding between dibasic acid 
and protein in hair

Dibasic acid has ions at both ends, allowing ionic bonding.

Mandom discovered the
ingredient that creates bonding! ingredient that creates ionic bonding!

Screening various dibasic acids,
we discovered α-ketoglutaric acid.

α-α-ketoglutaric acid penetrates into hair and forms ionic bonding. α-α-ketoglutaric acid penetrates into hair and forms ionic bonding.
New technology developed
by Mandom
With Inside Lock technology using α-ketoglutaric acid
Mandom has achieved both a natural finish + holding power that
keeps style all day long.

How was this done? We will tell you more!
Inside Lock technology:
4 Key Actions

ACTION1
Ingredients penetrate
into the core of the hair.

We compared the cross-sections of hair that was treated with α-ketoglutaric acid, the key ingredient of Inside Lock technology, with hair that was not treated: we verified that α-ketoglutaric acid had penetrated right into the core of the hair.

Permeation of α-ketoglutarate into hair

We compared the cross-sections of hair that was treated with α-ketoglutaric acid, the key ingredient of Inside Lock technology, with hair that was not treated: we verified that α-ketoglutaric acid had penetrated right into the core of the hair.

Test method
After hair had been immersed in α-ketoglutarate solution for 2 hours, the cut surface was mapped by Raman spectroscopy at the specific α-ketoglutarate peak of 1739 cm-1

ACTION2
Even in high humidity, forms and holds ionic bonding within hair.

We examined whether the α-ketoglutaric acid that has penetrated into the hair has bonded with the proteins in the
hair Using SAXS (Small-angle X-ray Scattering) method which can analyze substances in nano-size scale
At Kyoto University, where Mandom conducted joint research on Inside Lock technology.

What SAXS measures (image)

What SAXS measures (image) What SAXS measures (image)

By radiating X-ray beams onto hair, SAXS measures the bonding (regular array) of proteins within hair by analyzing the intensity of the scattered beam.
The scattering angle can tell us what substances the beams are acting on within the hair.
As shown in the graph above, high intensity of scattering indicates that the proteins are arrayed in regular order and bonded within the hair.

What We Found

Scattering intensity results after humid storage

Scattering intensity results after humid storage Scattering intensity results after humid storage

Under high humidity conditions, the hair treated with purified water showed irregularities in the structure of matrix protein inside the hair, whereas the hair with α-ketoglutaric acid penetration showed an orderly array of matrix protein, with structural integrity maintained.

Test method
After hair had been immersed in either 0.5% α-ketoglutarate solution or purified water for 2 hours, it was dried and placed in the SAXS sample cell.
X-ray was irradiated to the hair placed in the closed cell filled with warm water at 40°C.

Ordered structure of matrix protein
under high humidity
(Image on the basis of test results)

Ordered structure of matrix protein under high humidity(Image on the basis of test results)
This is evidence of the effect of α-ketoglutarate on hair matrix protein. α-ketoglutarate binded to hair protein and formed a robust, regularly arranged structure that was not affected by humidity.

ACTION3
Improves hold due to
high moisture resistance

To verify humidity resistance, we measured how much hair that is affected by humidity can hold onto shape.

The result was that groups of hair treated with α-ketoglutaric acid had
strong resistance against humidity.

Control over uncurling of hair
stored under high humidity

Control over uncurling of hair stored under high humidity Control over uncurling of hair stored under high humidity
Test method
30-cm long hair bundles were immersed in 0.5% aqueous solutions containing each treatment ingredient (or pure water for untreated hair) for 2 hours, then curled around a rod and dried for a day at a room temperature of 25°C and 60% RH.
After removing the rods, the hair bundles were left for 2 hours at a room temperature of 25°C and 80% RH, and hair length was measured over time.
*A=B:Length of the hair bundle before treatment(cm)-C:Length of the hair bundle at different measurement time points(cm) 試験方法

Under normal conditions, the curls straighten out because the hydrogen bonding inside hair breaks when the hair becomes damp. However, hair treated with α-ketoglutaric acid has an improved hold on the curls with strong control over uncurling.

ACTION4
Achieves natural texture just like untreated hair

We evaluated whether we had achieved a natural texture and finish that looked “like no hair styling agent had been used.” We put α-ketoglutaric acid, purified water, Mandom hair gel, and Mandom hair wax respectively on different bundles of hair and compared the luster on the surface of the hair.

Evaluation of shine
in hair bundles coated with samples

Test method
Hair appearance was observed after 0.4g of each sample was applied and soaked into the 20-cm long flat hair bundles and naturally air-dried.

Hair applied with setting polymer or wax showed up with strong luster. However, the hair that was treated with α-ketoglutaric acid had the same luster like the hair treated only with purified water,producing a natural texture.

Inside Lock technology
in summary

  • ACTION1Ingredients penetrate
    into the core of the hair
  • ACTION2Forms bonding with
    protein of the hair
  • ACTION3Improves hold due to
    high moisture resistance
  • ACTION4Achieves natural texture

Inside Lock technology produced 4 actions that beat the perpetual challenge faced
by styling agents: styling technology offering a natural finish but with a firm hold.

This newly developed styling technology will add more freedom and fun to your hair styling.
For the benefit of our customers, Mandom will continue tirelessly with our R&D to extend and advance this fun much, much further!

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