A method for predicting hair and facial characteristics using scalp stratum corneum cell characteristics

Abstract

To provide a method for estimating from stratum corneum cell properties of scalp skin, other areas, for example, a skin age, scalp skin, hair, facial skin and internal body properties, selection method of an appropriate care method of the scalp as well as the other areas by caring the scalp skin, and estimation support tool.SOLUTION: There is provided an estimation method of at least one of the following properties (i) to (iv) using stratum corneum cell properties of scalp skin as indices. (i) Facial skin properties, (ii) hair properties, (iii) scalp skin properties (excluding stratum corneum cell properties of the scalp skin), and (iv) internal body properties.EFFECT: A method makes it possible to provide property estimation information of multiple areas while minimizing a burden on a measurement object person, to provide cosmetics, etc. suitable for subjects and to be usable as a counseling tool. The method can thus provide users with beauty information such as care methods and care areas capable of providing higher effects according to users' worries and conditions.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for predicting hair properties, scalp properties (excluding scalp stratum corneum cell properties; the same applies hereinafter unless otherwise specified), facial skin properties, and internal body properties using information on scalp stratum corneum cell properties. [Background technology]

[0002] Conventionally, various observations, measurements, analyses, and evaluations have been made on 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 through a microscope. In the case of the properties of facial skin, the condition of each part has been confirmed, analyzed, and evaluated using visual inspection, a microscope, moisture measuring equipment, skin viscoelasticity measuring equipment, etc., and the properties inside the body have been confirmed, analyzed, and evaluated using a multi-function weighing scale, etc., but the relationship between the parts other than the parts being measured or observed, such as the scalp and facial skin, or the scalp and the properties inside the body, has rarely been considered.

[0003] Although the scalp is covered with hair, it is the part of the human body closest to the sun. Therefore, except for a few 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 it is thought to be the part of the body that is most susceptible to changes due to age and environment.

[0004] 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 hair increases, 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).

[0005] Regarding the relationship between the characteristics of facial stratum corneum cells and other characteristics, 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 to 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).

[0006] Regarding the relationship between scalp stratum corneum cell properties and other properties, the only information known is the relationship between scalp stratum corneum cell area and age (Non-Patent Document 2), and nothing is known about the relationships other than age.

[0007] Thus, although there are reports on the properties of the scalp, hair, facial skin, and body, there are very few reports relating them to the properties of scalp stratum corneum cells. Furthermore, in many cases of diagnosis of the properties of the scalp, hair, face, and body, the target area is directly used as the target area, and no method has been proposed for diagnosing the properties of other areas from the properties of scalp stratum corneum cells. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] Gen Soga, Age-related changes in scalp and hair and effective care.:Fragrance Journal.,(10)11-15,2012. [Non-Patent Document 2] Hideo Kuroda, Keiichiro Yoshihama, Mitsuko Sasagawa, Masami Suzuki, Changes in scalp and hair over time.: J.Soc.Cosmet.Chem.Jan.,26(4)254-261,1993. [Non-Patent Document 3] Genji Takahashi, Hiroko Watanabe, Hiroko Kumagai, Yasuhisa Nakayama, Physiological and morphological changes in facial skin with aging (Part 2): Journal of the Japanese Society of Cosmetic Technologists, 22-30, 1989. [Non-Patent Document 4] Jun Hirose, Hiroshi Tanaka, Tomio Okada, Hiroaki Konishi, Incidence and site difference of parakeratinocytes in human facial skin.: J.Soc.Cosmet.Chem.Jan.,23(1)5-8,1989. [Non-Patent Document 5] Kashibuchi, Nobuo, Matsumura, Yoshie, Development of a skin evaluation method using keratinocytes.: J.Soc.Cosmet.Chem.Jan.,23(1)55-57,1989. [Patent documents]

[0009] [Patent Document 1] JP 2019-51294 A Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention aims to provide a method for predicting the properties of other 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 not only the scalp but also other parts by caring for the scalp, and a prediction support tool. [Means for solving the problem]

[0011] [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 properties (ii) Hair properties (iii) Scalp characteristics (excluding scalp stratum corneum cell characteristics) (iv) Internal body condition [2nd Invention] The prediction method described in [1st Invention], wherein the indicator of stratum corneum cell properties is at least one selected from the area of ​​stratum corneum cells, layer delamination rate, and nucleated rate. [3rd Invention] A prediction method according to [1st Invention] or [2nd Invention], wherein the facial skin condition is the amount of sagging. [4th Invention] A method for predicting hair properties described in any one of [1st Invention] to [3rd Invention], wherein the hair properties are at least one selected from the total number of hairs, hair growth rate, and gray hair rate. [5th ​​Invention] A method for predicting scalp properties described in any one of [1st Invention] to [4th 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 body characteristic is at least one selected from body fat percentage, visceral fat level, BMI value, total body subcutaneous fat percentage, total body skeletal muscle percentage, and basal metabolism. [Seventh Invention] A method for predicting at least one selected from scalp moisture content and body basal metabolism using the scalp stratum corneum cell layer desquamation rate as an indicator. [8th 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] Obtain 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 regarding scalp characteristics (excluding information regarding scalp stratum corneum cell characteristics) (6) Information about internal physical conditions A method for predicting at least one of a subject's facial skin age, hair age, scalp age, and physical age by using at least one statistical relationship selected from (1) and / or (2) and (3) to (6) as population data and comparing the population data with scalp stratum corneum cell characteristic information of a given subject. [Tenth Invention] Obtain 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 regarding scalp characteristics (excluding information regarding scalp stratum corneum cell characteristics) (6) Information about internal physical conditions A method for predicting at least one of the following: (2) and (3) to (6) above, which is used as population data for each age group from (1) above, and which estimates at least one of the subject's facial skin age, hair age, scalp age, and physical age by comparing the population data with scalp stratum corneum cell characteristic information of a given subject. [Eleventh Invention] Obtain 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 regarding scalp characteristics (excluding information regarding scalp stratum corneum cell characteristics) (6) Information about internal physical conditions 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; By comparing the representative values ​​and / or representative characteristics with scalp stratum corneum cell characteristic information of any subject, An estimation support tool for estimating at least one selected from a facial skin age, a hair age, a scalp age, and a physical age of a 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 the method described in any one of claims 1 to 11, and suggesting a care method and care product suitable for the subject based on the prediction. Effect of the Invention

[0012] According to the method of the present invention, the properties of other parts such as the scalp, hair, facial skin, and internal body properties can be evaluated from the information on the properties of scalp stratum corneum cells, so that even if measurements are not performed for each part for which information is desired, information on the properties of scalp stratum corneum cells can be obtained by taking advantage of opportunities to observe the scalp, such as haircuts and hair care, or by utilizing the time spent with a customer for a long period of time at a body esthetic salon, etc., thereby making it possible to provide information on the properties of more parts while minimizing the burden on the subject, and this can be used as a counseling tool or to provide cosmetics suitable for the subject. Through this, it becomes possible to provide users with beauty information such as care methods and care parts that can provide greater effects according to their concerns and conditions. [Brief description of the drawings]

[0013] [Figure 1] Illustration of the ratio of ellipse length to width [Diagram 2] Illustrative diagram of displacement angle [Diagram 3] Relationship between scalp stratum corneum cell area and transepidermal water loss [Figure 4] Relationship between scalp stratum corneum cell area and scalp collagen density [Diagram 5] Relationship between scalp stratum corneum cell area and gray hair rate [Figure 6] Relationship between scalp stratum corneum cell area and total number of hairs [Figure 7] Relationship between scalp stratum corneum cell area and total body skeletal muscle ratio [Figure 8] Relationship between scalp stratum corneum cell area and visceral fat level [Figure 9] Relationship between scalp stratum corneum cell area and facial displacement angle [Figure 10] Relationship between scalp stratum corneum cell layer peeling rate and scalp stratum corneum moisture content [Figure 11] Relationship between scalp stratum corneum cell nucleation rate and age [Figure 12] Relationship between scalp stratum corneum cell ellipse ratio and facial displacement angle DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] 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.

[0015] 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.

[0016] The method of measuring the scalp stratum corneum cell area is not particularly limited and can be performed by any method. For example, the method of obtaining the area by observing the collected stratum corneum cells under a known microscope or microscope and analyzing the image after staining the collected stratum corneum cells, or the method of measuring the area by omitting the staining step of the collected stratum corneum cells, is specifically exemplified by the method of photographing the cells under ultraviolet light through a microscope or video microscope (JP Patent Publication No. 2003-315331), the method of irradiating the stratum corneum cells with ultraviolet light under observation through a microscope or microscope, and using the fluorescence intensity of the stratum corneum cells excited by ultraviolet light as an index (JP Patent Publication No. 2006-17688), and the method of using the autofluorescence image of the stratum corneum cells by a confocal laser microscope (JP Patent Publication No. 2009-247570). 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 vivascope) 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.

[0017] Stratum corneum cell peeling refers to the phenomenon in which keratinocytes are peeled off in layers when the stratum corneum of the skin is collected using adhesive tape or the like, and the ratio of peeled keratinocytes to the collected scalp keratinocytes is defined as the scalp stratum corneum cell peeling rate.

[0018] A nucleated cell refers to a cell that has a nucleus remaining within it, and the nucleated rate of scalp stratum corneum cells refers to the proportion of nucleated cells among the collected scalp stratum corneum cells.

[0019] The delamination rate and nucleated rate of the scalp stratum corneum can be confirmed by visual inspection, image processing of the obtained photographed image, computer technology such as artificial intelligence, etc. The specific calculation method is not particularly limited, but for example, a stratum corneum sample peeled and collected from the scalp is stained and observed under a known microscope, and the rate of delaminately peeled 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.

[0020] Facial skin properties refer to the facial morphological features and skin surface state that affect the appearance impression, and main examples include wrinkles, sagging, age spots, etc. As parameters for evaluating the morphological features and skin surface state, for example, in the case of sagging, the degree of sagging and viscoelasticity information of the facial skin are used, and in the case of age spots, color difference information such as brightness, saturation, melanin index, and redness of the facial skin is used.

[0021] 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 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 based on subcutaneous fat thickness, subcutaneous blood flow, collagen strength, and methods for applying shock waves to the evaluation site and evaluating it based on its propagation time (e.g., 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 (e.g., 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, it is possible to determine the distance of sagging, the direction of sagging, and its angle (for example, JP 10-43141 A, JP 2014-4105 A, Patent Application No. 2019-63072, etc.).

[0022] 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 range displayed on a screen when an image acquisition means such as a microscope is used at a specified 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 taking the average growth length per unit time of all hairs growing per unit area of ​​the scalp being evaluated, or by taking the average growth length per unit time of a specific hair.

[0023] Scalp collagen density refers to the density of collagen in the scalp dermis, and is said to be affected by aging and photoaging and change. 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, methods using a two-photon excitation microscope, OCT, or methods using an ultrasonic device. Invasive methods include, for example, methods of directly observing skin sections, but non-invasive methods that place less strain on subjects are preferred.

[0024] 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 measurement method, the transepidermal water loss is calculated from the water concentration gradient on the skin surface using 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 method, a sealed probe is placed on the skin surface, dry air or nitrogen gas is circulated over the skin surface inside the probe, and the transepidermal water loss can be calculated from the water content of the collected gas.

[0025] Internal physical characteristics refer to body fat percentage, visceral fat level, BMI value, total body subcutaneous fat percentage, total body skeletal muscle percentage, basal metabolism, etc., and are items that indicate the state of the fat and muscle that make up the body and are useful for health management, including the prevention and improvement of obesity. 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 that is 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.

[0026] There are several methods for measuring internal body properties, such as the method of calculating body fat percentage by pinching the subcutaneous fat with a tool called a subcutaneous fat thickness meter (caliper) and calculating the body density from the thickness, the 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, the air displacement method in which air pressure is applied to a sealed capsule and the body is calculated from the change in pressure, the dual energy X-ray absorptiometry in which two different wavelengths of X-rays are applied to the body and the body fat percentage is measured from the difference in the transmittance of each tissue in the body, and the method of taking cross-sectional images of the body using CT, MRI, or ultrasound to measure the thickness of fat, but these require large equipment and are a heavy burden on the subject. On the other hand, a body composition scale that uses the bioelectrical impedance 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.

[0027] The prediction support tool in the present invention is 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, for example, by simply observing the scalp stratum corneum cell area of ​​the subject, it becomes possible to immediately predict the overall position of any of the above skin age, scalp, hair, facial skin, and internal body properties during counseling. Conversely, it becomes possible to predict the 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. EXAMPLES

[0028] The relationship between scalp stratum corneum cell properties and parameters of skin age, scalp, hair, facial skin, and internal body properties will be specifically explained below based on examples. However, it goes without saying that the present invention is not limited to these examples.

[0029] <Subject> The subjects were 25 healthy women aged between 20 and 60. The number of subjects in each age group is shown in Table 1.

[0030] [Table 1]

[0031] <Measurement conditions> (1) Measurement room environmental conditions The environment in the measurement room was set to a temperature of 22°C and a humidity of 50%.

[0032] <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 of hair was shaved with clippers approximately 4 cm from the top of the 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 by the microscope was pressed against the shaved area with enough force to push down the growing hair, and photographs were taken.

[0033] <Measurement items of collected scalp stratum corneum cells> The stratum corneum adhesive portion of the tape was soaked in ethanol for 10 minutes, then air-dried for 10-30 minutes, and soaked in stratum corneum staining solution (0.1g naphthol blue black, 0.82g sodium acetate, 9g acetic acid, the remainder distilled water) for 30 minutes. After washing with running water for 10 minutes, it 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 scalp stratum corneum cell area and ellipse ratio The outline of the cell on the acquired and printed image was traced onto tracing paper and scanned using a scanner (Docucenter-V C4476 Fuji Xerox). After extracting the outline of the cell using image analysis software (WinROOF Mitani Shoji, the same applies below), the area within the outline and the ellipse ratio (ratio of the major and minor axes of an ellipse = "minor axis of ellipse" / "major axis of ellipse") were measured (see Figure 1). (2) Method for calculating the rate of scalp stratum corneum cell delamination The acquired image was decomposed into RGB using image analysis software to obtain an R image. This image was then binarized, and the area of ​​the entire stratum corneum cells obtained was calculated. The image was then binarized using various thresholds, and the threshold that most accurately extracted the layered area was selected by visual inspection, and binarization was then performed. The area of ​​the extracted cell layer detachment area was calculated, and its proportion in the total stratum corneum cell area was measured. (3) Method for calculating the nucleated rate of scalp stratum corneum cells In the acquired images, the ratio of the number of cells in which nuclei could be confirmed to the total number of cells in the stratum corneum was visually evaluated and calculated.

[0034] <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 microscopic image of the shaved area. The gray hair rate was calculated as the ratio of the number of gray hairs to the total number of hairs. (2) Hair growth rate (2-1) The first microscope image of the shaved area and the second microscope image of the same area were observed side by side, and for hairs that were visually confirmed in both images, the length from the root to the tip 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 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.

[0035] <Measurements for internal physical characteristics> Body fat percentage, visceral fat level, BMI value, total body subcutaneous fat percentage, total body skeletal muscle percentage, and basal metabolic rate 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, total body subcutaneous fat percentage, total body skeletal muscle percentage, and basal metabolic rate were calculated.

[0036] <Measurement items for facial skin properties> 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 can grasp the direction of skin sagging. The horizontal and vertical skin surface images obtained by the above 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 arrow pointing from the starting point to the end point was set as the radius, and the horizontal line (the line perpendicular to the direction of the Earth's gravity) passing through the end point was set as the X-axis. The positive angle (= θ1 in the figure) was calculated (see Figure 2).

[0037] <Scalp Measurement Items> (1) Transepidermal water loss from the scalp The amount of transepidermal water loss from the scalp was measured using a transepidermal water loss measuring device (Tewameter-TM300 Cortex Technology). With the subject lying supine, the shaved area was measured once, and the measured value was taken as the amount of transepidermal water loss from the scalp. (2) Scalp stratum corneum moisture content The moisture content of the scalp stratum corneum was measured using a skin surface moisture content measuring device (SKICON-200EX Yayoi). With the subject lying supine, 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 the scalp dermis Collagen density in the scalp dermis was measured using an ultrasound dermal imaging device (DermaLab Cortex Technology). The gain (sensitivity) was set to 7, and 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.

[0038] <Analysis> Analysis between each parameter was performed using Pearson's correlation analysis, and significant differences were examined using multiple comparison tests using the Tukey-Kramer method.

[0039] <Relationship between scalp stratum corneum cell area and other properties> (1) Relationship between scalp stratum corneum skin and scalp properties Figures 3 and 4 are scatter plots of scalp stratum corneum cell area, transepidermal water loss, and collagen density. A correlation was observed between scalp stratum corneum cell area, transepidermal water loss, and collagen density (R=-0.73 p<0.01, R=0.22 p<0.01). These results clearly show that as scalp stratum corneum cell area increases, transepidermal water loss decreases and collagen density increases. This suggests that scalp stratum corneum cell area can be used to predict scalp properties such as 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. A correlation was 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 as the scalp stratum corneum cell area increases, 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 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 plots 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 (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). These results clearly show that as scalp stratum corneum cell area increases, total body skeletal muscle ratio decreases, and visceral fat level, body fat percentage, total body subcutaneous fat percentage, and BMI increase. On the other hand, no correlation was confirmed between cheek and forehead stratum corneum cell area and these parameters of internal body properties. This suggests that scalp stratum corneum cell area can be used to estimate internal body properties more than facial stratum corneum cell area. (4) Relationship between scalp stratum corneum cell area and facial skin characteristics 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 scalp stratum corneum cell area and facial displacement angle. This result clearly shows that facial displacement angle increases with an increase in 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 area of ​​scalp stratum corneum cells can be used to predict facial displacement angle rather than facial stratum corneum cell properties.

[0040] <Relationship between scalp stratum corneum cell delamination rate, scalp stratum corneum cell nucleated rate, scalp stratum corneum cell ellipse ratio and other properties> (1) Relationship between scalp stratum corneum cell layer peeling rate and scalp and body characteristics FIG. 10 is a scatter plot of the scalp stratum corneum cell layer peeling rate and scalp stratum corneum moisture content. A correlation was found between the 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 found between the stratum corneum cell layer peeling rate of the cheek and forehead and age. This result clearly shows that as the scalp stratum corneum cell layer peeling rate increases, the scalp stratum corneum moisture content and age decrease. It was also found that the relationship with age is 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 scalp stratum corneum moisture content and scalp skin age. Furthermore, it was clear that as the scalp stratum corneum cell layer peeling rate increased, the basal metabolic rate decreased. On the other hand, no correlation was found between the cheek stratum corneum cell layer peeling rate and basal metabolic rate. This suggests that the scalp stratum corneum cell layer peeling rate can be used to predict internal physical conditions more effectively than the facial stratum corneum cell layer peeling rate. (2) Relationship between scalp stratum corneum cell nucleation rate and scalp and facial skin characteristics Figure 11 is a scatter plot of the scalp nucleated cell rate and age. A correlation was found 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 found between the nucleated cell rate of the cheeks or forehead and age. This makes it clear that the nucleated cell rate of the scalp is more likely to reflect the effects of aging than the face, and increases with age. From these results, it is believed 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 is more useful for predicting scalp properties such as scalp collagen density and for predicting the facial displacement angle than the nucleated rate of keratinocytes in the face. It is believed that this can be used to estimate the following: (3) Relationship between scalp stratum corneum cell ellipse ratio 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 found between the ellipse ratio of scalp stratum corneum cells and the facial displacement angle. These results clearly show that as the ellipse ratio of scalp stratum corneum cells decreases (cell shape shifts in the elongated direction), the facial displacement angle increases. This suggests that the ellipse ratio of scalp stratum corneum cells can be used to predict the facial displacement angle.

[0041] From these results, it is believed that by understanding the relationship between the information on the characteristics of scalp stratum corneum cells (area, rate of layer delamination, rate of nucleation, 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 will be possible to infer the characteristics of a subject's scalp, hair, facial skin, or internal body characteristics from the stratum corneum cells of the subject's 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.

[0042] 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

1. A method for predicting at least one of the total number of hairs, hair growth rate, and gray hair rate using scalp stratum corneum cell properties as an indicator.

2. The method according to claim 1 , wherein the indicator of stratum corneum cell properties is at least one selected from the group consisting of stratum corneum cell area, layer delamination rate, and nucleated rate.

3. A method for predicting hair properties of any subject using the method according to claim 1 or 2, and proposing a care method and a care product suitable for the subject based on the prediction.

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