JP2023012954A - Lip roughness evaluation method - Google Patents

Abstract

To provide a method of classifying a roughness state of a lip with a fine appearance that has no skin peeling.SOLUTION: A lip roughness evaluation method according to the present invention comprises: a step 1 of evaluating the presence/absence of skin peeling of a lip from a visible light irradiation image; and a step 2 of evaluating a luminance value of the lip from an ultraviolet ray irradiation image. It is preferable that the step 2 is performed after the step 1, and the ultraviolet ray irradiation image of a lower lip is used in the step 2.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for evaluating chapped lips.

The lips greatly contribute to the impression of an individual and are a site that is emphasized in daily life and beauty.

Conventionally, the methods described in Non-Patent Documents 1 to 3 are known as methods for evaluating chapped lips.

Tatsuya Himeno et al., "Development of a new evaluation method for chapped lips," 56th SCCJ Research Symposium Abstracts, 2005, p20-23 Ikuko Ueda et al., "Study on Rough Lips and Carbonylated Modified Proteins of Lip Corneocytes", 62nd SCCJ Conference Abstracts, 2008, p21-24 Eriko Tomoki et al., "Objective evaluation method for dry lips and its factors", Journal of Japanese Cosmetic Science Society, 2018, Vol. 42, No. 1, p1-8

Lip balms and the like are used to alleviate the roughness, but there are some cases where the effect of improving the roughness is not satisfactory. The inventors of the present invention proceeded with a more detailed study of the roughness state in order to examine whether it is possible to propose an improvement method suitable for each state by finely classifying the roughness state. They also found that even lips with a clean appearance without peeling can be classified into several rough states. They also found that the conventional methods described in Non-Patent Documents 1 to 3 are not suitable for classifying chapped lips without peeling.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method for classifying chapped lips that are clean in appearance without peeling.

That is, the present invention is as follows.
[1]
Step 1 of evaluating the presence or absence of peeling of the lips from the image irradiated with visible light;
Step 2 of evaluating the luminance value of the lips from the ultraviolet irradiation image;
A method for evaluating chapped lips, comprising:
[2]
The evaluation method for chapped lips according to [1], wherein the step 2 is performed after the step 1.
[3]
The method for evaluating chapped lips according to [1] or [2], wherein in step 2, an image of the lower lip irradiated with ultraviolet light is used.
[4]
The evaluation method for chapped lips according to any one of [1] to [3], wherein the ultraviolet irradiation image is an image obtained by irradiation with ultraviolet rays containing 365 nm.
[5]
The evaluation method for chapped lips according to any one of [1] to [4], wherein, in step 2, luminance values are evaluated from the ultraviolet irradiation image of the lower lip of the subject who did not have peeling in step 1.
[6]
Rough lip evaluation according to [5], wherein in step 2, the luminance value of the lip is evaluated using a luminance area ratio, which is a ratio of the area showing a luminance value equal to or higher than the luminance threshold to the total area of the lower lip. Method.
[7]
The method for evaluating rough lips according to [6], wherein in step 2, the luminance value of the lip is evaluated from the magnitude of the luminance area ratio with respect to the luminance area ratio threshold.
[8]
The method for evaluating chapped lips according to [6] or [7], wherein the brightness threshold is any one point in the range of 70 to 80.
[9]
The method for evaluating chapped lips according to any one of [6] to [8], wherein the brightness threshold is 75 and the brightness area ratio threshold is any one point in the range of 5 to 15%.
[10]
A method for determining a luminance threshold in the method for evaluating rough lips according to [6] or [7].
[11]
A method for determining a luminance area ratio threshold value in the evaluation method for chapped lips according to [7].
[12]
A lip counseling method including the method for evaluating chapped lips according to any one of [1] to [11].
[13]
The lip counseling method according to [12], comprising recommending a lip cosmetic and/or an external preparation following the method for evaluating chapped lips according to any one of [1] to [11].

ADVANTAGE OF THE INVENTION According to this invention, the method of classifying the chapped lip state which has a beautiful appearance without peeling can be provided.

It is a schematic diagram showing an example of a method for evaluating chapped lips according to the present embodiment. Moreover, it is explanatory drawing of rough lip evaluation of Example 1. FIG. 4 is a diagram for explaining evaluation of the presence or absence of skin peeling in step 1. FIG. FIG. 10 is a diagram for explaining evaluation of luminance values of lips from an ultraviolet irradiation image in step 2; (a) is an acquired ultraviolet irradiation image, (b) is an image obtained by cutting out the lower lip, and (c) is an image binarized with a luminance threshold. FIG. 10 is a diagram for explaining evaluation of luminance values of lips from an ultraviolet irradiation image in step 2; (a) is an image of a subject's lips irradiated with visible light, (b) is an image irradiated with ultraviolet light, and (c) is an image binarized with a luminance threshold. FIG. 10 is a diagram for explaining evaluation of luminance values of lips from an ultraviolet irradiation image in step 2; (a) is an image of a subject's lips irradiated with visible light, (b) is an image irradiated with ultraviolet light, and (c) is an image binarized with a luminance threshold. 4 is a table showing the results of Example 2. FIG. FIG. 10 is a table showing the matching rate between the luminance threshold, the luminance area ratio threshold, and the evaluation by a professional evaluator. FIG. 3 is a table showing the results of Example 3. FIG. 10 is a table showing the results of Example 6. FIG.

The evaluation method for chapped lips according to this embodiment includes step 1 of evaluating the presence or absence of peeling of the lips from a visible light irradiation image, and step 2 of evaluating the luminance value of the lips from an ultraviolet irradiation image. The evaluation method of the present embodiment may further include other steps such as lip parameter measurement.

The order of Step 1 and Step 2 is not particularly limited, but it is preferable to perform Step 2 after Step 1 because Step 1 is easier to analyze for determining whether or not the skin is peeled off.

(Step 1)
In step 1 above, the presence or absence of peeling of the lips is determined from the image irradiated with visible light. In addition, peeling of the lips may be used in combination with visual determination.

In step 1 above, if even one spot of skin peeling is observed on the lip from the visible light irradiation image, it is determined that the skin is peeling (Fig. 2).
Normally, old keratinocytes remain on the lips without exfoliation, resulting in a thickened portion, and the thickened portion peels off. Peeling includes a state in which the skin is completely peeled off, a state in which only the edges are peeled off, and the like, and refers to a state in which even a portion of the skin on the lip surface is peeled off. In the three circles in Fig. 2, the part inside the large circle in the center is the part where the skin is completely peeled off, and the part inside the small circle on the right is peeled only at the edges. This is the part where
An evaluator who determines peeling may be, for example, a lip expert evaluator. For example, evaluation may be performed by three evaluators (preferably professional evaluators), and peeling may be determined to be present when all of them determine that there is peeling.

The image irradiated with visible light is not particularly limited as long as it is an image capable of evaluating rough lips, and may be an image taken with a digital camera or the like under appropriate lighting.
The visible light irradiation image may be an image photographed under the same conditions as the ultraviolet irradiation image to be described later, except that the illumination conditions are changed. For example, the visible light irradiation image and the ultraviolet irradiation image may be acquired using different devices, or may be acquired using the same device (eg, VISIA-CR (manufactured by Canfield Scientific)).

As for the brightness at the time of photographing, it is preferable to photograph at an illuminance of 500 to 2000 lux. In addition, the image is an image of 3 million pixels or more (preferably 15 million pixels or more) (for example, an image of 2736 pixels or more in the horizontal direction and 1824 pixels or more in the vertical direction. Images occupying ~90% (preferably 60-80%).
When evaluating a plurality of subjects, images of all subjects are preferably images taken under the same conditions.

The visible light irradiation image is not particularly limited, and may be, for example, an image taken in the past, an image taken at a place different from the place to be evaluated, an image of a plurality of people, or the like.

The subject is not particularly limited as long as it is human, and it does not matter whether it is male or female. Also, the age of the subject is not particularly limited.

(Step 2)
In step 2 above, the brightness value of the lips is evaluated from the ultraviolet irradiation image. Step 2 above may be performed for the subject determined to have no skin peeling in step 1 above.
In the ultraviolet irradiation image, it can be evaluated that the lip is rough in areas with high luminance, and that the lip is not rough in areas with low luminance.

The ultraviolet irradiation image may be an image photographed under moderate ultraviolet irradiation. The ultraviolet rays preferably include at least a wavelength of 400 nm or less, more preferably ultraviolet rays including a wavelength of 365 nm.

In step 2 above, it is preferable to use an ultraviolet irradiation image of the lower lip from the viewpoint of enabling more accurate classification, as it has been reported that chapped lips occur specifically in the lower lip.

The luminance value can be obtained by converting the ultraviolet irradiation image into an image of 256 gradations. Specifically, it can be determined by the method described in Examples below.

At the time of imaging the UV irradiation image, by placing the scale that serves as the luminance reference near the lips and acquiring the image, the blur between subjects can be reduced and the luminance value can be analyzed more accurately.

In step 2 above, the UV irradiation image is analyzed to evaluate the luminance value of the lips. As a method of evaluating the luminance value, the luminance area ratio, which is the ratio of the area showing the luminance value equal to or higher than the luminance threshold to the total area of the lower lip (area showing the luminance value equal to or higher than the luminance threshold / total area of the lower lip ×100) (%) is preferably used as an index. The higher the luminance area ratio, the rougher the lips can be evaluated.
For example, the luminance area ratio of the lips is analyzed from the ultraviolet irradiation images of a plurality of subjects, and the degree of roughness of the lips can be compared by comparing the luminance area ratio values. This makes it possible to evaluate the degree of chapped lips even among subjects who have clean lips without peeling, and to propose lip cosmetic methods, moisturizers, etc. suitable for subjects.
The area showing a luminance value equal to or higher than the luminance threshold refers to the total area of the divisions showing a luminance value equal to or higher than the luminance threshold when the luminance value is measured for each fixed section of the lower lip. In the above analysis, one pixel of the lower lip image may be defined as one section, or a plurality of pixels (for example, any one of 2 to 100 pixels) may be defined as one section.
The brightness value may be measured by the same method for all subjects, and the target site (for example, the lower lip) may be cut from the ultraviolet irradiation image and the brightness value of each section may be measured using image analysis software. . It is preferable to use image processing software ImageJ for analysis of luminance values.

In step 2 above, as a method of evaluating the luminance value, it is preferable to evaluate the luminance value of the lip from the magnitude of the luminance area ratio with respect to the luminance area ratio threshold.
For example, create a univariate scatter diagram in which the luminance area ratios of multiple subjects are plotted on the vertical axis, and divide them into a group of subjects with a higher value than the luminance area ratio threshold and a group of subjects with a lower value. can be done. By adjusting the brightness area ratio threshold, it is possible to classify the lips into a group with less roughness and a group with more roughness, making it possible to classify the lips according to the proposed lip beauty method, moisturizer, and the like.

The method of determining the brightness threshold of this embodiment is the method of determining the above-described brightness threshold in the method of evaluating rough lips of this embodiment described above. The method of determining the luminance area ratio threshold value of this embodiment is the method of determining the above-mentioned luminance area ratio threshold value in the evaluation method for chapped lips of this embodiment described above. The luminance threshold and the luminance area ratio threshold may be determined separately or simultaneously.
The brightness threshold and/or the brightness area ratio threshold may be determined based on the characteristics of the lips.

When the brightness threshold is lowered, the brightness area ratio is calculated including a small brightness value, and the subject can be classified based on the brightness area ratio calculated including a relatively low brightness value in the ultraviolet irradiation image. For example, when trying to propose a beauty method that can be applied to a wide range of lips, from severely chapped lips to nearly healthy lips, by lowering the brightness threshold, the desired target person can can be classified.
On the other hand, if the luminance threshold is increased, the subject can be classified based on the luminance area ratio obtained only from the considerably high luminance value in the ultraviolet irradiation image. For example, when trying to propose a cosmetic method that can be applied to clean, unpeeled lips when the degree of chapped lips is severe, the target subject can be classified by increasing the brightness threshold.
Also, if there is a beauty treatment method to be proposed to a subject who has a high ratio of area showing luminance values in a specific range, two luminance thresholds are set and only subjects showing a ratio of luminance area between the thresholds are classified. is also possible.
One luminance threshold may be provided, or a plurality of luminance thresholds may be provided. By providing a plurality of brightness thresholds, it is possible to classify the rough state of the lips without peeling in more detail.

The above luminance threshold is classified based on visual and palpation evaluations, and the amount of water transpiration is different even though the amount of water is the same. From the viewpoint of being able to more accurately identify the classification based on that, it is preferably any one point in the range of 60 to 90, more preferably any one point in the range of 70 to 80, and still more preferably 75.

By lowering the brightness area ratio threshold, it is possible to classify subjects in a range including subjects with relatively low brightness area ratios to subjects with high brightness area ratios in the ultraviolet irradiation image. For example, when trying to propose a beauty method that can be applied to a wide range of lips, from severely chapped lips to nearly healthy lips, by lowering the brightness area ratio threshold, the target lips can be obtained. Subjects can be classified.
By increasing the brightness area ratio threshold, it is possible to classify subjects having a considerably high brightness area ratio in the ultraviolet irradiation image. For example, when trying to propose a cosmetic method that can be applied to clean lips without peeling and severely chapped lips, it is possible to classify the target subject by increasing the luminance area ratio threshold.
In addition, if there is a beauty treatment method to be proposed to a subject whose luminance area ratio is in a specific range, it is also possible to set two luminance area ratio thresholds and classify only the subjects showing a luminance area ratio between the thresholds. Become.
One luminance area ratio threshold may be provided, or a plurality of luminance area ratio thresholds may be provided. By providing a plurality of brightness area ratio thresholds, it is possible to classify the rough state of the lips without peeling in more detail.

The above luminance area ratio threshold is classified based on visual and palpation evaluations based on "lips are tight, dry to the touch, and the lips do not feel moist". From the viewpoint of being able to more accurately identify the classification based on the fact that the 10%.
Further, it is preferable that the luminance threshold is 75 and the luminance area ratio threshold is any one point in the range of 5 to 15%.

The sum of the brightness threshold value and the brightness area ratio threshold value (%) is preferably 65 to 110, more preferably 75, from the viewpoint of more accurately classifying the rough state of lips with a clean appearance without peeling. ~95, more preferably 80-90.

As a criterion for determining the brightness threshold and/or the brightness area ratio threshold, for example, lip parameters can be used.
Examples of decisions are given below.

The present inventors have studied the classification of lips with a clean appearance without peeling by professional evaluators. It was found that there was a tendency between one (state B) and one in a healthy state (state C). Criteria for classifying this tendency were found to be "a state in which the lips are tense, dry to the touch, and do not have a moist feeling on the lips".
Then, when comparing the univariate scatter diagram in which the luminance area ratio of multiple subjects is plotted on the vertical axis and the classification according to the above criteria, the luminance area ratio is high in state B, and the luminance area ratio is low in state C. found to do. That is, there was a tendency that the stronger the tension of the lips and the severer the dryness, the higher the luminance area ratio.
The brightness threshold value and the brightness area ratio threshold value can be determined so as to increase the rate of matching with the classification of state B and state C using the above criteria by a lip professional evaluator.
With this threshold setting, it is possible to propose lip cosmetic methods, moisturizing agents, etc. suitable for each condition based only on images without visual and palpable evaluation by a professional evaluator.

The present inventors further studied the characteristics of lips with a clean appearance without peeling, and found that although the moisture content did not change between the group with a high luminance area ratio and the group with a low luminance area ratio, the luminance area ratio It was found that there was a tendency for the amount of water loss (TEWL) to be high in the group with a high brightness, and to be low in the group with a low luminance area ratio. They also found that a positive correlation was observed in a scatter diagram plotting the luminance area ratio on the vertical axis and the amount of water evaporation on the horizontal axis.
The luminance threshold value and the luminance area ratio threshold value can be set based on the amount of water evaporation. For example, by measuring the amount of water loss on the lips of a plurality of people (e.g. 100 people) with a clean appearance without peeling, a standard for the amount of loss of water with a significant difference between the group with high water loss and the group with low water loss is set. Then, a luminance value or a luminance area ratio corresponding to the reference may be set as a threshold.
By setting this threshold value, it is possible to classify subjects with a high amount of water loss, although the amount of water does not change, without measuring the amount of water content and the amount of water loss. It becomes possible.
In addition, the moisture content and moisture loss of the lips can be measured by the method described in Examples below.

The present inventors further studied the characteristics of lips with a clean appearance without peeling, and found that the group with a high luminance area ratio had high elasticity (Δf), and the group with a low luminance area ratio had elasticity (Δf). was found to be low.
The luminance threshold value and the luminance area ratio threshold value can be set based on the value of elasticity (Δf). For example, the elasticity (Δf) of the lips with a clean appearance without peeling is measured for a plurality of people (for example, 100 people), and there is a significant difference between the group with high elasticity (Δf) and the group with low elasticity (Δf). A reference may be set, and a luminance value or luminance area ratio corresponding to the reference may be set as a threshold. In addition, between the group with high elasticity (Δf) and the group with low elasticity, a criterion is set so that the difference in Δf value is 20 or more (preferably 30 or more), and the luminance value or luminance area ratio corresponding to the criterion is set. may be set as the threshold.
With this threshold setting, subjects with high elasticity (Δf) can be classified only from images without measuring elasticity (Δf), and suitable lip cosmetic methods, moisturizers, etc. can be proposed.
The elasticity (Δf) can be measured by the method described in Examples below.

The method for evaluating rough lips, the method for determining the brightness threshold value, and the method for determining the brightness area ratio threshold value according to the present embodiment are, for example, classifying lips that are free from peeling and have a clean appearance, and are suitable for the subject. It can be used when suggesting cosmetics or beauty medicine.

In the method for evaluating rough lips described above, for example, a luminance threshold and a luminance area ratio threshold are determined in advance from ultraviolet irradiation images of a plurality of persons (for example, 100 persons, etc.), and then evaluation of rough lips in the present embodiment described above. The method may assess chapped lips in a subject. The measured values and captured images of the subject may be input as a database, and additional measured values and captured images may be stored in the database each time a new subject is measured. By determining the threshold in advance, it is possible to evaluate the lips even if the subject is in a remote location if there is an image irradiated with visible light and an image irradiated with ultraviolet light. Measured values and photographed images can be stored in the device, and the accuracy of lip classification can be improved. From the measurements of the remote subject, the above database, the above system are used to evaluate the classification of chapped lips, and the data associated with the pre-determined chapped lips classification and the lip cosmetic and/or topical preparation. can be used to display recommended lip cosmetics and/or topical preparations that can be proposed to the target person at a remote location, and to propose counseling including recommendations for beauty methods and beauty medicines.
In addition, the tendency of chapped lips may differ depending on the region and time. For example, by changing the threshold for each region and time, it is possible to propose beauty methods and cosmetic medicines suitable for each region and time.
Further, in the method for evaluating rough lips of the present embodiment, one type of evaluation is performed using a combination of a luminance threshold value and a luminance area ratio threshold value from one visible light irradiation image and one ultraviolet irradiation image. Alternatively, a plurality of combinations of luminance thresholds and luminance area sum thresholds may be used to simultaneously perform a plurality of types of evaluations (e.g., evaluation of water loss and elasticity).
In addition, recommended lip cosmetics and external preparations include, for example, skin peeling observed by visual and palpation evaluation, a hard surface, and a low moisture content. Specifically, it is preferable to add an aqueous component, a water-retaining substance, or a substance with high lip permeability. In order to suppress the amount of water transpiration, it is preferable to give a highly water-occlusive formulation or drug to the subjects in the high group. It is preferable to use a material that is difficult to absorb, but it is not particularly limited.

The lip counseling method of the present embodiment includes the rough lip evaluation method of the present embodiment described above. For example, after evaluating chapped lips, a method of lip counseling may be suggested based on the results of the chapped lips evaluation.
Examples of the counseling method include proposal of lip cosmetics and external preparations, explanation of the subject's current lip condition, advice on improvement of the lip condition, and the like. The above counseling may be performed at the same place as the subject, or may be performed from a remote location.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

(Example 1)
Three subjects A, B, and C were evaluated for chapped lips according to the following method.
Visible light irradiation images and ultraviolet irradiation images of each subject were obtained using VISIA-CR (manufactured by Canfield Scientific). The images were acquired with LIGHTING MODES set to Standard 1 or UV Fluorescence and a Resolution of about 20 million pixels.
The presence or absence of skin peeling was determined from the obtained visible light irradiation image. In addition, "with skin peeling" means a state in which even a part of the skin on the lip surface is peeled off. Circled locations in FIG. 2 are locations where the skin is peeled off. Skin peeling was observed in subject A, and subjects B and C had no peeling (Fig. 1). FIG. 2 is an enlarged view of the lips of subject A with peeling.
Next, for two subjects B and C who had no skin peeling, luminance values were evaluated by the following method using ultraviolet irradiation images. The lower lip portion was cut out from the ultraviolet irradiation image, and the brightness of each pixel was measured using the image analysis software "ImageJ" (Figs. 1 and 3). The brightness was obtained by converting the brightness of the image into a 256-gradation grayscale image. Specifically, the analysis was performed using the Color Threshold function of ImageJ.
Then, the brightness value was binarized with a brightness threshold value of 75 (FIG. 3). Then, the luminance area ratio of each subject was calculated using the following formula.
Brightness area ratio (%) = area showing brightness value of 75 or more / total area of lower lip x 100
Then, they were classified into subject B (FIG. 4) with a high luminance area ratio (35.04%) and subject C (FIG. 5) with a low luminance area ratio (0.09%).

Visual evaluation of the lips by a professional evaluator was performed on the three subjects after classification, and it was confirmed that only subject A had peeling. In addition, when a professional evaluator performed a visual evaluation and a palpation evaluation, the lips of subject B were tense and dry when touched, and the lips did not feel moist, and subject C was healthy. Met. Based on the above evaluation, lips with a clean appearance without peeling could be classified.
Further, when the water loss (TEWL) and elasticity (Δf) of Subjects B and C were measured by the method described later, Subject B was higher in both values.

(Example 2)
57 subjects (25 males and 32 females) in their twenties to fifties were evaluated for chapped lips a total of four times at different times.
A visible light irradiation image and an ultraviolet irradiation image of each subject were acquired in the same manner as in Example 1, and the presence or absence of skin peeling was determined from the visible light irradiation image.
In the image irradiated with visible light, luminance values of the lips were evaluated in the same manner as in Example 1 for a total of 141 subjects who had no skin peeling.
The brightness thresholds are set to 55, 60, 70, 75, 80, and 90, and the brightness area ratio thresholds are 2.5%, 5%, 7.5%, 10%, 12.5%, Analyzes were performed with the settings set to 15%, 17.5%, and 20%. Then, after analysis with each threshold, it was classified into a group that was more than the luminance area ratio threshold and a group that was less than the luminance area ratio threshold. Visual and palpation evaluations were carried out, and a group in which the lips were "tight, dry to the touch, and no moist feeling on the lips" (state B) and a group in a healthy state (state C). classified into
Then, the number of subjects who were above the luminance area ratio threshold and the evaluation by the professional evaluator was in state B and the number of subjects who were less than the luminance area ratio threshold and the evaluation by the professional evaluator was The matching rate, which is the ratio of the total number of subjects who were in condition C, was calculated from the following formula.
Match rate (%) = {(Number of subjects whose luminance area ratio threshold is equal to or higher and whose evaluation by the professional evaluator is state B) + (Less than the luminance area ratio threshold and whose evaluation by the professional evaluator is state C Subjects)}/Number of all subjects without peeling x 100
The results are shown in FIG. Note that "-" in the figure indicates unevaluated.
When the brightness threshold was 75 and the brightness area percentage threshold was 10%, the rate of agreement with the status BC classification by the professional evaluator was the highest. In particular, when the sum of the luminance threshold value and the luminance area ratio threshold value was 82.5 to 90, the match rate was extremely high at 83% or more.

(Example 3)
Subjects were classified in the same manner as in Example 2, except that the brightness threshold was set to 75 and the brightness area ratio threshold was set to 10%. Then, they were classified into those with peeling (group A), no peeling and a brightness area ratio threshold of 10% or more (group B), and no skin peeling and a brightness area ratio of less than 10% (group C).
In addition, visual evaluation, palpation evaluation, water content, water loss (TEWL) and elasticity (Δf) of all subjects were measured by the method described later. The results are shown in FIG.
Group B had the same average water content as Group C, but the average water loss was significantly higher. Although a significant difference in elasticity (Δf) between B and C could not be confirmed, a tendency of group A>group B>group C was observed.

(Example 4)
In the same manner as in Example 3, the amount of water and the amount of water loss were measured for the subject who did not have peeling in the image irradiated with visible light in Example 2. Then, when the luminance threshold value and the luminance area ratio threshold value were set so that there was no change in the water content and there was a significant difference in the water evaporation amount, the luminance threshold value was 75 and the luminance area ratio threshold value was 10%.

(Example 5)
Δf was measured in the same manner as in Example 3 for the subject who did not have peeling in the image irradiated with visible light in Example 2. Then, the luminance threshold value and the luminance area ratio threshold value were set so that the group having the luminance area ratio threshold value or more and the group having the luminance area ratio value less than the luminance area ratio threshold value had a significant difference in Δf. was 15%.

(Example 6)
Six subjects were evaluated for chapped lips on 12 consecutive days.
For the evaluation of rough lips, subjects were classified in the same manner as in Example 2, except that the brightness threshold was set to 75 and the brightness area ratio threshold was set to 10%. Then, they were classified into those with peeling (group A), no peeling and a brightness area ratio threshold of 10% or more (group B), and no skin peeling and a brightness area ratio of less than 10% (group C).
The results are shown in FIG. Note that "-" in the figure indicates unevaluated.

[evaluation]
Evaluation in each example was performed by the following method.

(1. Visual evaluation)
After three professional evaluators shared the reference lip condition in advance, visual evaluation was performed according to the following criteria based on the impression when the subject's lips were visually observed. Scores were determined in consultation with three expert raters.
In addition, since there is an oversight in the visual evaluation, even if it is "peeled" in the method of evaluating the peeling of the lips from the image irradiated with visible light, the visual evaluation may give the following rank 4 or less. Therefore, even if there is peeling in the image irradiated with visible light, the visual evaluation value is Rank 5 or less (FIG. 7).
-standard-
1: No dryness observed, moist feeling, no roughness observed 2: No dryness observed, slight moisture observed, no roughness observed 3: No dryness observed, no roughness observed 4 : Slightly dry, but not rough 5: Slight peeling, dry roughness 6: Peeling, more dry, rough 7: Clear peeling Injury is seen, and dryness is strong and roughness is recognized

(2. Palpation evaluation)
After three professional evaluators shared the smoothness of the lip surface, etc., as a reference in advance, based on the impression when touching the lip surface of the subject, the lip smoothness, etc. was evaluated by palpation according to the following criteria. Scores were determined in consultation with three expert raters.
-standard-
1: Moisturizing and sticky, but not bulky and smooth condition 2: Moisturizing and moist, but not dry and smooth condition 3: Dry No dryness, no dryness and smooth state 4: Feels a little dry, but no dryness and smooth state 5: Feels a little dry and feels dry State of dryness 7: A state in which there is strong dryness and a strong feeling of roughness and stiffness

(3. Water content)
Using a Skin Moisture Sensor MY-808S (manufactured by Scalar Corporation), the moisture content of the lower lip center was measured. The measurement conditions were a temperature of 22±2° C. and a humidity of 50% RH.
Measurements were taken 5 times, and the average value of the 3 measurements excluding the maximum and minimum values was adopted.

(4. Amount of water evaporation)
Using VAPOMETER (manufactured by Delfin), the amount of water loss in the center of the lower lip was measured. The measurement conditions were STD mode, nail probe, temperature 22±2° C., and humidity 50% RH.
Measurements were taken 5 times, and the average value of the 3 measurements excluding the maximum and minimum values was adopted.

(5. Elasticity evaluation)
Using VENUSTRON (manufactured by AXIOM), the elasticity of the center of the lower lip was measured. The change in frequency (Δf) was measured when it penetrated 2 mm at 2 mm/s.
Measurements were performed 10 times, 5 measurements were selected so that the standard deviation was the smallest, and the average value was adopted.

Claims (13)

Step 1 of evaluating the presence or absence of peeling of the lips from the image irradiated with visible light;
Step 2 of evaluating the luminance value of the lips from the ultraviolet irradiation image;
A method for evaluating chapped lips, comprising: 2. The method for evaluating chapped lips according to claim 1, wherein said step 2 is performed after said step 1. 3. The method for evaluating chapped lips according to claim 1 or 2, wherein in step 2, an image of the lower lip irradiated with ultraviolet light is used. The method for evaluating chapped lips according to any one of claims 1 to 3, wherein the ultraviolet irradiation image is an image obtained by irradiating ultraviolet rays containing 365 nm. 5. The method for evaluating chapped lips according to claim 1, wherein, in said step 2, luminance values are evaluated from said ultraviolet irradiation image of the lower lip of a subject who did not have peeling in said step 1. 6. Evaluation of rough lips according to claim 5, wherein in said step 2, the luminance value of the lip is evaluated using a luminance area ratio, which is a ratio of the area showing a luminance value equal to or higher than a luminance threshold to the total area of the lower lip. Method. 7. The method for evaluating rough lips according to claim 6, wherein in said step 2, the luminance value of the lips is evaluated from the magnitude of said luminance area ratio with respect to a luminance area ratio threshold. 8. The method for evaluating chapped lips according to claim 6, wherein the luminance threshold is any one point in the range of 70-80. The evaluation method for chapped lips according to any one of claims 6 to 8, wherein the brightness threshold is 75, and the brightness area ratio threshold is any one point in the range of 5 to 15%. 8. A method for determining a brightness threshold in the method for evaluating rough lips according to claim 6 or 7. A method for determining a luminance area ratio threshold in the evaluation method for chapped lips according to claim 7. A lip counseling method comprising the method for evaluating chapped lips according to any one of claims 1 to 11. The lip counseling method according to claim 12, comprising recommending lip cosmetics and/or external preparations following the method for evaluating chapped lips according to any one of claims 1 to 11.

Images