JP2024054324A - Method for predicting hair and facial characteristics using scalp stratum corneum cell characteristics - Google Patents

Abstract

[Problem] The present invention provides a method for predicting other body parts, such as skin age, scalp, hair, facial skin, and internal body properties, from scalp stratum corneum cell property information, and provides a method for selecting an appropriate care method for the scalp as well as other body parts by caring for the scalp, and a prediction support tool. [Solution] A method for predicting at least one of the following properties (i) to (iv) using scalp stratum corneum cell properties as an index: (i) facial skin properties (ii) hair properties (iii) scalp properties (excluding scalp stratum corneum cell properties) (iv) internal body properties [Effect] The method according to the present invention makes it possible to provide prediction information for properties of many more body parts while minimizing the burden on the subject, and can be used to provide cosmetics suitable for the subject, and as a counseling tool. Through this, it becomes possible to provide users with beauty information such as care methods and care areas that provide higher effects according to their concerns and conditions. [Selected Figure] Figure 3

Description

The present invention relates to a method for predicting hair properties, scalp properties (excluding scalp stratum corneum cell properties; the same applies below unless otherwise specified), facial skin properties, and internal body properties using information on scalp stratum corneum cell properties.

Traditionally, various observations, measurements, analyses, and evaluations have been made of the properties of the scalp, hair, and face. For example, the degree of damage to hair is often evaluated visually, and the condition of the scalp is often evaluated visually using a microscope. In the case of facial skin properties, in addition to visual inspection and a microscope, moisture measuring devices and skin viscoelasticity measuring devices have been used, and for internal body properties, a multi-function weighing scale has been used to confirm, analyze, and evaluate the condition of each part. However, there has been little consideration of the relationship between parts other than the parts being measured or observed, such as between the scalp and facial skin, or between the scalp and internal body properties.

Although the scalp is covered with hair, it is the part of the human body that is closest to the sun, and therefore, except for some people who use hats, parasols, or special sunscreens, it is the part of the body that is directly exposed to the harsh effects of ultraviolet rays, and is thought to be the part of the body that changes most due to age and environment.

Regarding the relationship between scalp characteristics and other characteristics of the head, it is known that with age, the scalp becomes redder, the number of hairs decreases, gray hairs increase, hair thickness varies, and the proportion of thin hairs increases (Patent Document 1), the scalp becomes harder (Non-Patent Document 1), and the area of stratum corneum cells on the scalp increases (Non-Patent Document 2).

Regarding the relationship between facial stratum corneum cell properties and other properties, it is known that the area of stratum corneum cells in the cheeks increases with age (Non-Patent Document 3), that the rate of nucleated stratum corneum cells above the cheekbones in women peaks in their 20s and 30s and thereafter decreases with age (Non-Patent Document 4), and that the rate of delamination of stratum corneum cells on the face is not correlated with age but is related to skin type (Non-Patent Document 5).

Regarding the relationship between scalp stratum corneum cell properties and other properties, the only information available is the relationship between scalp stratum corneum cell area and age (Non-Patent Document 2), and nothing is known about relationships other than age.

Though there are reports on the characteristics of the scalp, hair, facial skin and body, there are very few reports relating them to the characteristics of scalp stratum corneum cells. Furthermore, in most cases of diagnosis of the characteristics of the scalp, hair, face and body, the target area is directly examined, and currently no method has been proposed for diagnosing the characteristics of other areas from the characteristics of scalp stratum corneum cells.

Hajime Soga, Age-related changes in scalp and hair and effective care. Fragrance Journal., (10) 11-15, 2012. Hideo Kuroda, Keiichiro Yoshihama, Mitsuko Sasagawa, Masami Suzuki, Changes in scalp and hair with age. J. Soc. Cosmet. Chem. Jan., 26(4) 254-261, 1993. Takahashi, Motoji, Watanabe, Hiroko, Kumagai, Hiroko, Nakayama, Yasuhisa. Physiological and morphological changes in facial skin with aging (part 2). Journal of the Japanese Society of Cosmetic Technologists, 22-30, 1989. Hirose, Jun., Tanaka, Hiroshi, Okada, Tomio, Konishi, Hiroaki. Incidence and site difference of parakeratinocytes in human facial skin. J. Soc. Cosmet. Chem. Jan., 23(1) 5-8, 1989. Kashibuchi, Nobuo, Matsumura, Yoshie, Development of a skin evaluation method using keratinocytes. J. Soc. Cosmet. Chem. Jan., 23(1) 55-57, 1989.

JP 2019-51294 A

The present invention aims to provide a method for predicting other body parts, such as skin age, scalp, hair, facial skin, and internal body properties, from scalp stratum corneum cell property information, and to provide a method for selecting appropriate care techniques for the scalp as well as other body parts by caring for the scalp, and a prediction support tool.

[First Invention]
A method for predicting at least one of the following properties (i) to (iv) using scalp stratum corneum cell properties as an indicator:
(i) facial skin characteristics; (ii) hair characteristics; and (iii) scalp characteristics (excluding scalp stratum corneum cell characteristics).
(iv) Intrabody properties [Second invention] The method of prediction described in [First invention], wherein the indicator of stratum corneum cell properties is at least one selected from the area of stratum corneum cells, the rate of layer delamination, and the rate of nucleation.
[3rd Invention] A method of predicting facial skin condition according to [1st Invention] or [2nd Invention], wherein the facial skin condition is the amount of sagging.
[Invention 4] The method for predicting hair condition described in any one of [Invention 1] to [Invention 3], wherein the hair property is at least one selected from the total number of hairs, hair growth rate, and gray hair rate.
[Fifth Invention] A method for predicting scalp properties described in any one of [First Invention] to [Fourth Invention], wherein the scalp properties are at least one selected from scalp collagen density and scalp transepidermal water loss.
[6th Invention] A prediction method described in any one of [1st Invention] to [5th Invention], wherein the internal physical characteristic is at least one selected from body fat percentage, visceral fat level, BMI value, whole-body subcutaneous fat percentage, whole-body skeletal muscle percentage, and basal metabolism.
[Seventh Invention] A method for predicting at least one selected from scalp moisture content and basal body metabolism using the scalp stratum corneum cell layer peeling rate as an indicator.
[Eighth Invention] A method for predicting at least one selected from the amount of sagging facial skin and scalp collagen density using the nucleated rate of scalp stratum corneum cells as an indicator.
[Ninth Invention]
Obtaining at least one piece of information selected from the following (1) and (2) and (3) to (6) from a plurality of subjects in advance;
(1) Age information (2) Information on scalp stratum corneum cell characteristics (3) Information on facial skin characteristics (4) Information on hair characteristics (5) Information on scalp characteristics (excluding information on scalp stratum corneum cell characteristics)
(6) Information regarding internal body characteristics: A method for predicting at least one selected from the group consisting of (1) and/or (2) and (3) to (6) by using population data as population data and comparing the population data with scalp stratum corneum cell characteristic information of a given subject to predict at least one selected from the facial skin age, hair age, scalp age, and physical age of the subject.
[Tenth Invention]
Obtaining at least one piece of information selected from the following (1) and (2) and (3) to (6) from a plurality of subjects in advance;
(1) Age information (2) Information on scalp stratum corneum cell characteristics (3) Information on facial skin characteristics (4) Information on hair characteristics (5) Information on scalp characteristics (excluding information on scalp stratum corneum cell characteristics)
(6) A method for estimating at least one of the following: facial skin age, hair age, scalp age, and physical age of a subject by comparing at least one statistical relationship selected from (2) and (3) to (6) above, which is obtained from (1) above as population data for each age group, with scalp stratum corneum cell property information of a given subject.
[Eleventh Invention]
Obtaining at least one piece of information selected from the following (1) and (2) and (3) to (6) from a plurality of subjects in advance;
(1) Age information (2) Information on scalp stratum corneum cell characteristics (3) Information on facial skin characteristics (4) Information on hair characteristics (5) Information on scalp characteristics (excluding information on scalp stratum corneum cell characteristics)
(6) Information regarding internal physical characteristics: At least one or more statistical relationships selected from (2) and (3) to (6) are used as population data by age group from (1);
determining representative values and/or representative characteristics for each age group from the population data;
An estimation support tool that estimates at least one selected from a subject's facial skin age, hair age, scalp age, and physical age by comparing the representative value and/or representative characteristic with scalp stratum corneum cell characteristic information of any subject.
[Twelfth Invention]
A method for predicting at least one of the facial skin characteristics, hair characteristics, scalp characteristics (excluding scalp stratum corneum characteristics), and internal body characteristics of a given subject using a method according to any one of claims 1 to 11, and for suggesting a care method and care product suitable for the subject based on the prediction.

The method of the present invention makes it possible to evaluate the properties of other parts of the body, such as the scalp, hair, facial skin, and internal body properties, from information on scalp stratum corneum cell properties. Therefore, even without measuring each part for which information is desired, information on scalp stratum corneum cell properties can be obtained during opportunities to observe the scalp, such as haircuts and hair care, or by utilizing the time spent with a customer at a body esthetic salon or other such salon. This makes it possible to provide inferred information on the properties of more parts of the body while minimizing the burden on the subject, and can be used to provide cosmetics and other products suitable for the subject, or as a counseling tool. Through this, it becomes possible to provide users with beauty information such as care methods and care parts that will provide greater results, tailored to their concerns and conditions.

Illustration of the ratio of ellipse length to width Illustrative diagram of displacement angle Relationship between scalp stratum corneum cell area and transepidermal water loss Relationship between scalp stratum corneum cell area and scalp collagen density Relationship between scalp stratum corneum cell area and gray hair rate Relationship between scalp stratum corneum cell area and total number of hairs Relationship between scalp stratum corneum cell area and total body skeletal muscle ratio Relationship between scalp stratum corneum cell area and visceral fat level Relationship between scalp stratum corneum cell area and facial displacement angle Relationship between scalp stratum corneum cell layer peeling rate and scalp stratum corneum moisture content Relationship between scalp stratum corneum cell nucleation rate and age Relationship between scalp stratum corneum cell ellipse ratio and facial displacement angle

The method for collecting scalp stratum corneum cells is not particularly limited and can be any method. For example, they can be collected by tape stripping or rubbing the skin with cotton. In addition, the area to be collected can be directly immersed in a dilute surfactant aqueous solution and rubbed to disperse the cells. Even if hair or other substances other than the stratum corneum are included during collection, there is no problem as long as they do not affect the measurement.
In order to minimize the effect of scalp sunburn on the evaluation, it is preferable to collect stratum corneum peeling samples from areas other than the parting and whorl. In order to increase the objectivity of the evaluation, it is preferable to compare samples from the same areas.

The scalp stratum corneum cell area is the area of the internal region surrounded by the outline of a single cell that constitutes the stratum corneum.
The number of cells to be used for calculating the area from the collected scalp stratum corneum cells is not particularly limited, but 10 or more cells are preferable, and the more the number, the higher the accuracy. When determining the relationship with other parameters, the scalp stratum corneum cell area may be determined using the average area per stratum corneum cell, or the total area if the number of cells used is constant.

The method for measuring the scalp stratum corneum cell area is not particularly limited and can be performed by any method. For example, the area can be obtained by staining the collected stratum corneum cells, observing them under a known microscope or a microscope, and analyzing the images, or the area can be measured directly without the staining step of the collected stratum corneum cells. Specifically, the area can be measured by a method of photographing the stratum corneum cells under ultraviolet light through a microscope or a video microscope (JP Patent Publication No. 2003-315331), a method of irradiating ultraviolet light on the stratum corneum cells under observation through a microscope or a microscope, and using the fluorescence intensity of the stratum corneum cells excited by ultraviolet light as an index (JP Patent Publication No. 2006-17688), a method of using an autofluorescence image of the stratum corneum cells by a confocal laser microscope (JP Patent Publication No. 2009-247570), and the like.
Furthermore, the steps from staining to using image processing software can be omitted by using computer technology such as artificial intelligence (AI), etc. In other words, the area of the collected stratum corneum cells may be calculated without staining the stratum corneum cells.
In addition, by using a confocal laser microscope (such as a vivascoscope) or a multiphoton microscope, the stratum corneum peeling process may be omitted and the properties of the stratum corneum cells may be calculated by a method such as directly observing the skin.

Stratum corneum cell peeling refers to the phenomenon in which keratinocytes peel off in layers when the stratum corneum of the skin is collected using adhesive tape or the like, and the rate of scalp keratinocytes that have peeled off is defined as the scalp keratinocyte peeling rate.

Nucleated cells refer to cells that have a nucleus remaining within them, and the nucleated rate of scalp stratum corneum cells refers to the percentage of nucleated cells among the collected scalp stratum corneum cells.

The rate of delamination and the rate of nucleated cells of the scalp stratum corneum can be confirmed by visual inspection, image processing of the captured images, computer technology such as artificial intelligence, etc. There are no particular limitations on the specific calculation method, but for example, a stratum corneum sample peeled and collected from the scalp can be stained and observed under a known microscope, and the rate of delamination of stratum corneum cells and the rate of nucleated cells can be calculated based on the total number of collected stratum corneum cells or the number of stratum corneum cells per visual field.

Facial skin properties refer to the facial morphological features and skin surface condition that affect the appearance, and include wrinkles, sagging, age spots, etc. that increase with age. Parameters for evaluating the morphological features and skin surface condition include, for example, the degree of sagging and viscoelasticity information of the facial skin for sagging, and color difference information such as brightness, saturation, melanin index, and redness of the facial skin for age spots.

Sagging skin, which sags due to gravity, is one of the main changes in appearance that occur with aging. It is said to occur mainly due to the decline in physiological functions of the body caused by aging, such as a decline in skin viscoelasticity and muscle function and an increase in subcutaneous fat. The amount of sagging skin is a quantitative representation of these phenomena.
The amount of sagging skin can be, for example, changes in the position, direction, distortion, etc. on the skin caused by sagging of the upper or middle part of the skin, and can be understood as displacement distance, displacement direction, displacement angle, azimuth angle, etc. (see, for example, Patent Application No. 2019-63072).
As a method for evaluating the amount of sagging skin, there are methods for evaluating it by subcutaneous fat thickness, subcutaneous blood flow, collagen strength, and methods for applying shock waves to the evaluation site and evaluating it by its propagation time (for example, JP 2010-51717 A, JP 10-95713 A, JP 2011-15862 A, etc.). On the other hand, as a method for directly measuring the measurement surface, a method for photographing and analyzing a three-dimensional vertical face using a sampling moire camera or the like, and a method for evaluating it using a 3D scanner camera are known (for example, Dent. J. Iwate. Med. Univ., 13: 197, 1988., J. Soc. Cosmet. Chem. Jan., 50 (3) 222-226, 2016., etc.). In addition, there is a two-dimensional method in which reference points and measurement points are marked on the surface of the skin, horizontal and vertical photographs of the face are taken, and the distance and direction of movement of the measurement points are calculated based on the reference points. Using this method, the sagging distance, sagging direction, and angle can be determined (for example, JP 10-43141 A, JP 2014-4105 A, JP 2019-63072 A, etc.).

Hair properties refer to the state of hair, such as the total number of hairs, the percentage of gray hairs, the rate of hair growth, the thickness of hair, the shape of the cross section of hair, etc. This includes the state of hair growing from the scalp, falling out, and after washing with a hair wash.
The total number of hairs may be the total number of hairs growing per unit area of the scalp to be evaluated, or may be the black portion obtained by performing black and white binarization on an image obtained by an image acquisition means such as a microscope. The unit area is not particularly limited, and may be, for example, the area displayed on a screen when an image acquisition means such as a microscope is used at a certain magnification (hereinafter the same).
The gray hair rate can be calculated by measuring the ratio of the number of gray hairs to the total number of hairs growing per unit area of the scalp to be evaluated.
The hair growth rate may be calculated by using the average growth length per unit time of all hairs growing per unit area of the scalp being evaluated, or by using the average growth length per unit time of a specific hair.

Scalp collagen density indicates the density of collagen in the scalp dermis, and is said to change due to the effects of aging and photoaging. The measurement method may be any method, whether non-invasive or invasive. Non-invasive methods may be, for example, methods using a confocal laser microscope, a two-photon excitation microscope, an OCT, or an ultrasound device. An invasive method is, for example, a method of directly observing a skin slice, but a non-invasive method that places less strain on the subject is preferred.

Transepidermal water loss is the amount of water that evaporates from the body unconsciously through the stratum corneum, and the devices used to measure it can be broadly divided into open and closed types.
In the open type measurement method, the transepidermal water loss is calculated from the water concentration gradient on the skin surface according to Fick's law. A hollow cylindrical probe designed to have two humidity sensors positioned at regular intervals on the skin surface is placed on the skin to measure the water content at two points. On the other hand, in the closed type, a sealed probe is placed on the skin surface, dry air or nitrogen gas is circulated on the skin surface inside the probe, and the transepidermal water loss can be calculated from the water content of the collected gas.

Internal physical characteristics refer to body fat percentage, visceral fat level, BMI value, total body subcutaneous fat percentage, total body skeletal muscle percentage, basal metabolic rate, etc., and are items that indicate the state of the fat and muscle that make up the body, which can be used as a reference when preventing and improving obesity and managing health.
Specifically, body fat percentage is the proportion of body weight that is made up of body fat, visceral fat level is the area of body fat that is around the internal organs, BMI value is a standard for determining obesity by checking the balance between weight and height, total body subcutaneous fat percentage is the proportion of body weight that is made up of subcutaneous fat accumulated under the skin, total body skeletal muscle percentage is the proportion of body weight that is made up of skeletal muscle, and basal metabolism refers to the minimum amount of energy needed to maintain life, such as maintaining body temperature and breathing.

Methods for measuring internal body properties include, for example, a method for calculating body fat percentage by pinching the subcutaneous fat with a device called a subcutaneous fat thickness measuring device (caliper) and calculating the body density from the thickness; underwater weighing method (underwater weight measurement method) in which body weight is measured underwater and body density is calculated from the difference between body weight on land; air displacement method in which air pressure is applied in a sealed capsule and the body is calculated from the change in pressure; dual energy X-ray absorptiometry in which the body is exposed to X-rays of two different wavelengths and body fat percentage is measured from the difference in the transmittance of each tissue in the body; and a method in which cross-sectional images of the body are taken using CT, MRI, or ultrasound to measure fat thickness. However, these require large equipment and place a heavy burden on the person being measured. On the other hand, a body composition scale that uses bioimpedance method, which can calculate the electrical resistance value from a weak current passed through the whole body from electrodes on both hands and feet, can easily measure multiple parameters in a short time.

The prediction support tool of the present invention is intended to assist in predicting and evaluating the degree of scalp properties, hair properties, facial skin properties, and internal body properties from scalp stratum corneum cell information in a simple manner. Specifically, by using a prediction standard tool that diagrams and visualizes the relationship between the items to be predicted, such as age, scalp properties, hair properties, facial skin properties, and internal body properties, according to the degree of scalp stratum corneum cell properties, it becomes possible to instantly predict the overall position of any of the above skin age, scalp, hair, facial skin, and internal body properties during counseling, simply by observing the scalp stratum corneum cell area of the subject. Conversely, it becomes possible to predict scalp stratum corneum cell properties based on any of the scalp, hair, facial skin, and internal body properties. In addition, for example, a plurality of stages divided according to the degree of scalp stratum corneum cell area may be investigated and prepared in advance, and other properties may be predicted by identifying the stage to which the scalp stratum corneum cell area of the subject corresponds.

The following provides a detailed explanation of the relationship between scalp stratum corneum cell properties and parameters of skin age, scalp, hair, facial skin, and internal body properties based on examples. However, it goes without saying that the present invention is not limited to these examples.

<Subjects>
The subjects were 25 healthy women aged from their 20s to 60s. The number of subjects in each age group is shown in Table 1.

<Measurement conditions>
(1) Measurement Room Environmental Conditions The measurement room environment was set to a temperature of 22° C. and a humidity of 50%.

<How to collect scalp stratum corneum cells and photograph the shaved area>
(1) The subject was placed in a supine position. An area of 6 mm x 6 mm hair was shaved with clippers at a position approximately 4 cm from the top of the subject's head toward the right ear, and the shaved area was lightly wiped with water-soaked cotton.
(2) Using a stratum corneum checker (plastic plate type, manufactured by Promo Tools), stratum corneum cells were collected from the shaved area.
(3) On the day of shaving (first time) and the day after (second time), the surface of a petri dish attached to the area to be photographed with the microscope was pressed against the shaved area with enough force to push down the growing hair, and photographs were taken.

<Measurement items of collected scalp stratum corneum cells>
The stratum corneum adhesive portion of the tape was immersed in ethanol for 10 minutes, then air-dried for 10-30 minutes, and then immersed in stratum corneum staining solution (0.1 g naphthol blue black, 0.82 g sodium acetate, 9 g acetic acid, the remainder distilled water) for 30 minutes. After washing with running water for 10 minutes, the tape was air-dried overnight. Images of the stratum corneum cells after the above treatment were taken using a microscope with a photographing function (BZ-X700 KEYENCE, 20x magnification).
(1) Method for calculating the area and ellipse ratio of scalp stratum corneum cells The outline of the cells on the obtained and printed out image was traced on tracing paper and scanned with a scanner (Docucenter-V C4476 Fuji Xerox). The outline of the cells was extracted using image analysis software (WinROOF Mitani Shoji, the same applies below), and the area within the outline and the ellipse ratio (ratio of the major axis and minor axis of an ellipse = "minor axis of ellipse" / "major axis of ellipse") were measured (see Figure 1).

(2) Calculation method of the keratinocyte layer peeling rate of scalp keratinocytes The acquired image was decomposed into RGB on image analysis software to obtain an R image. This image was binarized, and the area of the entire keratinocyte obtained was calculated. Furthermore, the image was binarized with various thresholds, and the threshold that most accurately extracted the layered part was selected by visual inspection, and binarization was performed. The area of the extracted cell layer peeled part was calculated, and the ratio of the area to the total keratinocyte area was measured.

(3) Method for calculating the rate of nucleated scalp stratum corneum cells The rate of cells in which nuclei could be confirmed in the total number of stratum corneum cells in the acquired images was calculated by visual evaluation.

<Hair measurement items>
(1) Total number of hairs and gray hair rate The total number of hairs and the number of gray hairs were visually calculated from the second microscope image of the shaved area. The gray hair rate was defined as the ratio of the number of gray hairs to the total number of hairs.
(2) Hair growth rate (2-1) The first microscopic image of the shaved area and the second microscopic image of the same area were observed in parallel, and the length from the root to the tip of the hair that was visually confirmed in both images was calculated using image analysis software.
(2-2) For the same hair, the difference in length obtained from both images was calculated.
(2-3) The time elapsed from the first photographing time to the second photographing time was calculated, and the growth rate was calculated by dividing the time elapsed by the value obtained in (2-2).
(2-4) The average growth rate determined in (2-3) was calculated for all hairs in each panel.

<Measurements of internal physical properties>
Body fat percentage, visceral fat level, BMI value, total body subcutaneous fat percentage, total body skeletal muscle percentage, and basal metabolism were measured using a body composition monitor (Karada Scan HBF-375, Omron Corporation).
Participants stood barefoot on the measuring device and were measured once, after which their body fat percentage, visceral fat level, BMI value, whole-body subcutaneous fat percentage, whole-body skeletal muscle percentage, and basal metabolic rate were calculated.

<Facial skin condition measurement items>
The subject was placed in a seated position, and measurement points were marked at the intersections of the vertical downward direction from the corners of the eyes and the horizontal outward direction from the corners of the mouth, where sagging is thought to occur significantly, and reference points were marked on multiple areas that do not move much when the posture is changed. Next, the subject's face was photographed in a supine position, and then while keeping the angle and distance between the face and the camera lens constant, the subject's face was photographed in a seated position. The former was a horizontal position skin surface image, and the latter was a vertical position skin surface image.
The angle between the horizontal line and the line connecting each measurement point on the horizontal and vertical skin surface images was defined as the "displacement angle" that allows the direction of skin sagging to be grasped, and the horizontal and vertical skin surface images obtained by the above-mentioned method were superimposed using a reference point as a guide, and the measurement point on the horizontal skin surface image was set as the starting point, and the measurement point on the vertical skin surface image was set as the end point. The positive angle (= _θ1 in the figure) was calculated when the horizontal line (the line perpendicular to the direction of gravity of the earth) passing through the end point was set as the X-axis (see Figure 2).

<Scalp measurement items>
(1) Scalp transepidermal water loss Scalp transepidermal water loss was measured using a transepidermal water loss measuring device (Tewameter-TM300 Cortex Technology). The shaved area was measured once in a supine position, and the measured value was taken as the scalp transepidermal water loss.
(2) Moisture content of scalp stratum corneum The moisture content of scalp stratum corneum was measured using a skin epidermal stratum corneum moisture content meter (SKICON-200EX Yayoi). With the patient in supine position, the moisture content at the measurement point (shaved area) was measured five times, and the average value was taken as the moisture content of the stratum corneum.
(3) Collagen density in scalp dermis Collagen density in the scalp dermis was measured using an ultrasonic dermis imaging device (DermaLab Cortex Technology).
The gain (sensitivity) was set to 7, the shaved area was measured five times in the supine position, and the average value of the Int. parameter was taken as the collagen density value in the dermis.

<Analysis>
Analysis between each parameter was performed by Pearson's correlation analysis, and significant differences were examined by multiple comparison test using the Tukey-Kramer method.

<Relationship between scalp stratum corneum cell area and other properties>
(1) Relationship between scalp stratum corneum cell skin and scalp properties Figures 3 and 4 are scatter plots of scalp stratum corneum cell area, scalp transepidermal water loss, and scalp collagen density. A correlation was observed between scalp stratum corneum cell area, scalp transepidermal water loss, and scalp collagen density (R = -0.73 p < 0.01, R = 0.22 p < 0.01). This result clearly shows that as the scalp stratum corneum cell area increases, the scalp transepidermal water loss decreases and the scalp collagen density increases. This suggests that the scalp stratum corneum cell area can be used to estimate scalp properties such as scalp transepidermal water loss and collagen density.

(2) Relationship between scalp stratum corneum cell area and hair properties Figures 5 and 6 are scatter plots of scalp stratum corneum cell area, gray hair rate, and total hair number. Correlations were observed between scalp stratum corneum cell area and gray hair rate, total hair number, and hair growth rate (R=0.31 p<0.01, R=-0.30 p<0.01, R=-0.25 p<0.01). These results clearly show that with an increase in scalp stratum corneum cell area, the gray hair rate increases and the total hair number and hair growth rate decrease. On the other hand, no correlation was observed between age and the total hair number or hair growth rate. This suggests that scalp stratum corneum cell area can be used to predict hair properties rather than using age information.

(3) Relationship between scalp stratum corneum cell area and internal body properties Figures 7 and 8 are scatter diagrams of scalp stratum corneum cell area, total body skeletal muscle ratio, and visceral fat level. Correlations were observed between scalp stratum corneum cell area and total body skeletal muscle ratio, visceral fat level, body fat percentage, total body subcutaneous fat percentage, and BMI value (R = -0.42 p < 0.01, R = 0.38 p < 0.01, R = 0.37 p < 0.01, R = 0.34 p < 0.01, R = 0.27 p < 0.01). From these results, it was clear that with an increase in scalp stratum corneum cell area, the total body skeletal muscle ratio decreased, and the visceral fat level, body fat percentage, total body subcutaneous fat percentage, and BMI value increased. On the other hand, no correlation was confirmed between the stratum corneum cell area of the cheeks and forehead and these internal body property parameters. This suggests that the scalp stratum corneum cell area can be used to predict internal body properties more effectively than the facial stratum corneum cell area.

(4) Relationship between scalp stratum corneum cell area and facial skin properties Figure 9 is a scatter plot of scalp stratum corneum cell area and facial displacement angle. A correlation (R = 0.30 p < 0.01) was found between the scalp stratum corneum cell area and the facial displacement angle. This result clearly shows that the facial displacement angle increases with an increase in the scalp stratum corneum cell area. On the other hand, no correlation was found between the stratum corneum cell area of the cheeks and forehead and the facial displacement angle. This suggests that the scalp stratum corneum cell area can be used to estimate the facial displacement angle rather than the facial stratum corneum cell properties.

<Relationship between scalp stratum corneum cell delamination rate, scalp stratum corneum cell nucleated rate, scalp stratum corneum cell ellipse length ratio and other properties>
(1) Relationship between scalp stratum corneum cell layer peeling rate and scalp properties and internal body properties Figure 10 is a scatter diagram of scalp stratum corneum cell layer peeling rate and scalp stratum corneum moisture content. Correlations were observed between scalp stratum corneum cell layer peeling rate and scalp stratum corneum moisture content, as well as age and basal metabolism (R = -0.28 p < 0.01, R = -0.27 p < 0.01, R = -0.24 p < 0.01). On the other hand, the scalp stratum corneum cell layer peeling rate was significantly higher than that of the cheek and forehead, and no correlation was confirmed between the stratum corneum cell layer peeling rate of the cheek and forehead and age. From these results, it was clear that the scalp stratum corneum moisture content and age decreased with an increase in the scalp stratum corneum cell layer peeling rate. It was also found that the relationship with age was stronger in the scalp than in the face. This suggests that the scalp stratum corneum cell layer peeling rate can be used to estimate the moisture content of the scalp stratum corneum and the skin age of the scalp. Furthermore, it was clear that basal metabolism decreases as the scalp stratum corneum cell layer peeling rate increases. However, no correlation was found between the cheek stratum corneum cell layer peeling rate and basal metabolism. This suggests that the scalp stratum corneum cell layer peeling rate can be used to estimate internal physical conditions more effectively than the facial stratum corneum cell layer peeling rate.

(2) Relationship between the scalp nucleated cell rate and scalp and facial skin characteristics Figure 11 is a scatter plot of the scalp nucleated cell rate and age. A correlation was observed between the scalp nucleated cell rate and age, as well as between scalp collagen density and facial displacement angle (R = 0.45 p < 0.01, R = -0.40 p < 0.01, R = 0.24 p < 0.01). On the other hand, no correlation was confirmed between the nucleated cell rate and age in the cheeks and forehead. Therefore, it was clear that the nucleated cell rate in the scalp is more likely to reflect the effects of aging than the face, and increases with age. From these results, it is considered that the scalp nucleated cell rate can be used to estimate the skin age of the scalp.
Furthermore, it was clear that as the nucleated rate of scalp keratinocytes increased, the collagen density of the scalp decreased and the facial displacement angle increased. On the other hand, no correlation was found between the nucleated rate of keratinocytes in the cheeks and forehead and the facial displacement angle. This suggests that the nucleated rate of scalp keratinocytes can be used to predict scalp properties such as scalp collagen density and to predict the facial displacement angle rather than the nucleated rate of facial keratinocytes.

(3) Relationship between the ellipse ratio of scalp stratum corneum cells and facial skin characteristics Figure 12 is a scatter plot of the ellipse ratio of scalp stratum corneum cells and the facial displacement angle. A correlation (R = -0.30 p < 0.01) was observed between the ellipse ratio of scalp stratum corneum cells and the facial displacement angle. This result clearly shows that the facial displacement angle increases with a decrease in the ellipse ratio of scalp stratum corneum cells (cell shape shifts in the elongated direction). This suggests that the ellipse ratio of scalp stratum corneum cells can be used to predict the facial displacement angle.

From these results, it is believed that by understanding the relationship between information on the characteristics of scalp stratum corneum cells (area, layer delamination rate, nucleation rate, etc.) previously obtained using the method of the present application and skin age, scalp, hair, facial skin characteristics, or internal body characteristics, and using the results, it is possible to infer the scalp, hair, facial skin characteristics, or internal body characteristics of a subject from the stratum corneum cells of the scalp, and by understanding these by age, it is possible to infer the level of each characteristic of the subject.
In addition to the amount of sagging skin, the above method can also be used to understand the relationship between spots, wrinkles, dullness, pores, and other skin properties.

As described above, by using the method of the present invention, it is possible to comprehensively predict scalp properties, hair properties, facial skin properties, and internal body properties, as well as the relationship between these and age, from the properties of scalp stratum corneum cells, making it possible to make better suggestions for improving the scalp, hair, face, and body.

Claims (4)

A method for predicting hair properties using the properties of scalp stratum corneum cells as an indicator. The method according to claim 1, wherein the indicator of stratum corneum cell properties is at least one selected from the area of stratum corneum cells, the rate of delamination, and the rate of nucleation. The method according to claim 1 or 2, wherein the hair property is at least one selected from the total number of hairs, the hair growth rate, and the gray hair rate. A method for predicting hair properties of a given subject using the method according to any one of claims 1 to 3, and proposing a hair care method and a hair care product suitable for the subject based on the prediction.