JP3974835B2 - Method for evaluating the percentage of free unsaturated fatty acids in sebum - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for evaluating sebum on the skin surface.
[0002]
[Prior art]
Sebum is secreted from the sebum line on the human skin surface. Sebum has been said to be an important component that suppresses the transpiration of moisture from the skin and imparts smoothness to the skin.
[0003]
However, according to recent research, when ultraviolet rays are excessively irradiated to the skin, free radicals and active oxygen are generated, and the mechanism by which these substances oxidize sebum and produce lipid peroxide is clarified. It has been pointed out that it can cause skin disorders.
[0004]
And among the sebum lipids composed of free fatty acids, triglycerides, etc., the more free fatty acids, the greater the amount of transpiration of water from the skin (transdermal water loss: TEWL), thus inhibiting the barrier function of the stratum corneum. (For example, refer nonpatent literature 1).
[0005]
In addition, it has been reported that unsaturated fatty acids are particularly problematic among free fatty acids (see, for example, Non-Patent Document 2).
[0006]
Furthermore, it is common knowledge that excessive sebum is the cause of makeup loss, but it has recently been reported that among the components in sebum, especially free unsaturated fatty acids are the main cause of makeup loss. (Non-Patent Document 3).
[0007]
For this reason, knowing the behavior of free unsaturated fatty acids in the sebum on the skin surface is the degree of lipid peroxide in the skin, in other words, the degree of aging, the degree of destruction of the barrier function of the stratum corneum, in other words, the degree of rough skin, This is useful in evaluating important cosmetic factors such as the ease of makeup breakup.
[0008]
By the way, in order to know the behavior of free fatty acids in the sebum on the skin surface, in general, the present condition is based on a chemical analysis or instrumental analysis method for a skin sample separated from the skin.
[0009]
For example, the measurement result of sebum composition by infrared spectroscopy has been reported. In this case, the amount of sebum is measured by analyzing a sebum sample or the like transferred by pressing aluminum foil on the skin (see, for example, Patent Document 1). In addition, triglycerides, free fatty acids, squalene, and wax esters, which are main components of sebum, are quantified (see, for example, Non-Patent Document 4 and Patent Document 2).
[0010]
However, as described above, all of the conventional methods use a sample isolated from a human as a measurement target (measurement in an ex vivo state), for example, as a part of cosmetic canceling at a cosmetic store. It is not necessarily suitable as a method used for performing.
[0011]
For this reason, as a method for measuring the amount of sebum in an in vivo state simply and accurately, the surface of the skin is irradiated with ultraviolet rays, the amount of excited fluorescence emitted is detected as an electrical signal, and the amount of sebum is measured from a calibration curve. A method has been proposed (see, for example, Patent Document 3).
[0012]
[Patent Document 1]
JP-A-2-220630 [Patent Document 2]
JP-A-5-60686 [Patent Document 3]
Japanese Patent Laid-Open No. 3-123533 [Non-Patent Document 1]
Yahaneda et al. Proceedings of the 21st Annual Meeting of the Japanese Cosmetic Science Society, 1996p.50)
[Non-Patent Document 2]
Maruyama et al. JSCCJ. 2001 35 (2), 133-140
[Non-Patent Document 3]
Nomura et al. JSCCJ. 1999 33 (3), 254-266
[Non-Patent Document 4]
Mijo et al. J. Soc. Cosmet. Japan Vol.31, No.2 1997
[Problems to be solved by the invention]
However, as described above, the method described in Patent Document 3 is for determining the amount of sebum at the measurement site, and not for measuring the amount of free unsaturated fatty acid in the sebum.
[0013]
This invention is made | formed in view of said subject, and it aims at providing the method of evaluating the free unsaturated fatty acid rate of the sebum on the skin surface.
[0014]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have conducted intensive studies. As a result, there is a significant difference between the light emission state of the skin surface and the percentage of free unsaturated fatty acids in the sebum on the skin surface when the skin surface is irradiated with ultraviolet rays. The inventors have found that there is a relationship, and have reached the present invention.
[0015]
The method for evaluating the percentage of free unsaturated fatty acids in sebum according to the present invention is a method for evaluating the percentage of free unsaturated fatty acids in sebum for evaluating cosmetic failure factors, and is used for observing the site of the skin surface of a plurality of preliminary subjects. Irradiate ultraviolet rays, obtain an image by imaging the site to be observed that developed color, and evaluate the free unsaturated fatty acid rate of sebum on the site to be observed on the skin surface of a plurality of preliminary subjects by a predetermined means, A preliminary process for associating the image with the result of the evaluation, and irradiating the observation target site on the skin surface of the subject with ultraviolet rays, imaging the observation target site exhibiting color development, obtaining an image, and obtaining in the preliminary step And an evaluation step for evaluating the ratio of free unsaturated fatty acids in the sebum on the skin surface of the subject based on the association information.
[0016]
Here, the light applied to the surface of the skin is preferably ultraviolet light that is irradiated in a state where external light is substantially blocked, but includes light having a wavelength other than the ultraviolet region such as visible light as well as ultraviolet light. May be. In addition, sebum is, in other words, total lipid, and contains free fatty acid as a component together with components such as triglyceride, squalene, and wax ester as described above. Therefore, the percentage of free unsaturated fatty acids in sebum means the content of free unsaturated fatty acids in the total lipid. Among the free fatty acids, examples of free saturated fatty acids include palmitic acid and stearic acid, and examples of free unsaturated fatty acids include permitoleic acid and oleic acid. The predetermined evaluation means refers to an existing method such as chemical analysis for quantifying total lipids containing free unsaturated fatty acids. Further, associating the image with the evaluation result is obtained by measuring the area of the light emitting portion in the image to obtain quantitative data, and quantitatively associating the quantitative data with the evaluation result, that is, Although it is preferable to obtain correlation data, the present invention is not limited to this. For example, a method may be used in which representative images having different free unsaturated fatty acid ratios are selected and used as limit samples. In the former case, the subject also measures the area of the luminescent part in the image to obtain quantitative data, and evaluates the percentage of free unsaturated fatty acids numerically based on the correlation data. In the latter case, the subject's image The free unsaturated fatty acid ratio is evaluated at a plurality of levels by contrasting with an image as a limit sample. Near ultraviolet rays are preferably used as the ultraviolet rays.
[0017]
Thereby, it is possible to evaluate the free unsaturated fatty acid ratio of sebum simply and quickly with the subject's skin as a direct target.
[0018]
In this case, in the preliminary step, the image is subjected to image processing to obtain quantification data to obtain correlation data with the evaluation result, and in the evaluation step, the image is subjected to image processing to obtain quantification data, When the percentage of free unsaturated fatty acids on the skin surface of the subject is quantitatively evaluated based on the correlation data, the percentage of free unsaturated fatty acids in sebum is more preferably determined based on more quantitative data obtained by image processing. Can be evaluated.
[0019]
Further, in this case, if an image is taken using a microscope equipped with a black light as an ultraviolet ray source, the free unsaturated fatty acid ratio of sebum can be evaluated by a simple method using a simple device. It is suitable as a tool when performing cosmetics counseling or the like at a store or developing cosmetics.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment (hereinafter referred to as this embodiment) of a method for evaluating the percentage of free unsaturated fatty acids of sebum according to the present invention will be described below with reference to the drawings.
[0021]
First, an apparatus (hereinafter simply referred to as an apparatus) used for performing the method for evaluating the percentage of free unsaturated fatty acids in sebum according to the present embodiment will be described with reference to FIGS.
[0022]
As illustrated in FIG. 1, the apparatus 10 includes an illumination unit 12, an image acquisition unit 14, a recording unit 16, an analysis unit 18, an output unit 19, and a control unit 20.
[0023]
As an apparatus provided with the illumination unit 12 and the image acquisition unit 14, for example, a microscope shown in FIG. 2 can be used.
[0024]
The microscope 22 includes a housing 28 having a distal end side as an observation cylinder part 24 and a proximal end side bent by a required angle with respect to the observation cylinder part 24 as a gripping cylinder part 26.
[0025]
The observation cylinder part 24 forms an opening 30 at the tip on the optical axis A set at the axial center. The opening 30 is formed with a size sufficient to obtain an imaging region having a size of 8.0 mm × 6.2 mm. A black light fluorescent tube (hereinafter, simply referred to as black light) 32 formed in an annular shape and a reflecting plate 34 are provided around the observation cylinder portion 24. The black light 32 can be used by switching near-ultraviolet rays of 352 nm, 360 nm, 365 nm, and 368 nm as peak wavelengths. Among these, a peak wavelength of 368 nm is preferably used. Instead of the black light fluorescent tube 32, a plurality of black light LEDs may be arranged in a ring shape.
[0026]
On the optical axis A of the observation cylinder portion 24, an observation lens barrel 40 having a magnifying optical system 36 and a color CCD element 38 is provided. An annular white light fluorescent tube or white light LED is provided together with the black light 32.
[0027]
In FIG. 2, reference numeral 41 is a CCU (Central Control Unit) for displaying an image signal output from the color CCD 28 on a monitor, and reference numeral 42 indicates an inverter unit serving as a driving power source for the black light 32. .
[0028]
The microscope 22 configured as described above irradiates near ultraviolet rays in a dark room state where external light is blocked by irradiating near ultraviolet rays from the black light 32 in a state where the observation site surface B is in close contact with the opening 30. The observation site surface B can be irradiated.
[0029]
The reflected light from the observation site surface B is output as an enlarged color image signal and sent to the recording unit 16. If necessary, when the black light 32 is turned off and the white light fluorescent tube or the like is turned on, the observation site surface B can be observed only with visible light.
[0030]
The recording unit 16 is a recording element such as a hard disk. In the recording unit 16, each image data such as an original image from the image acquisition unit 14 and a processed image from the analysis unit 18 is recorded, and the area of the light emitting portion and free unsaturated fatty acid in the image data prepared in advance. Correlation data with rate measurements are recorded. Instead of the correlation data, a plurality of image data with known free unsaturated fatty acid ratios may be recorded as limit samples.
[0031]
The analysis unit 18 is a personal computer, for example. The analysis unit 18 performs numerical analysis (numerical processing) after performing image processing such as binarization processing on the image data recorded in the recording unit. Further, the analysis unit 18 calculates the free unsaturated fatty acid ratio for new image data based on the correlation data of the recording unit 16.
[0032]
The output unit 19 is, for example, a CRT display or a printer. The output unit 19 calculates an original image stored in the recording unit 16, an image after analysis processing such as a binarized image recorded in the recording unit 16 after analysis by the analysis unit 18, and a free unsaturated fatty acid ratio. These correlation data or limit sample images can be displayed in appropriate combination. The output unit 19 can present the free unsaturated fatty acid ratio obtained from the image data in the analysis unit 18 in the form of a numerical table or a graph.
[0033]
Further, when acquiring the original image from the observation target, the image information can be displayed on the output unit 19 online. At this time, by presenting previously acquired images at the same time, it is possible to specify the same part when measuring the same part.
[0034]
The control unit 20 includes a CPU and controls each of the above units. The control unit 20 can input attribute data such as the name and age of the subject to be observed, measurement date and time, measurement site, and the like, and stores these data in the recording unit 16 in correspondence with the original image data. And can be presented from the output unit 19. Similarly, the binarized image data analyzed by the analysis unit 18 can be associated with attribute data and the like, stored in the recording unit 16, and presented from the output unit 19.
[0035]
A method for evaluating the percentage of free unsaturated fatty acids in sebum according to the present embodiment using the apparatus 10 configured as described above will be described below.
[0036]
First, see FIG. 3 and FIG. 4 regarding the knowledge obtained by the present inventor regarding the relationship between the light emission state of the skin surface when the skin surface is irradiated with ultraviolet rays and the percentage of free unsaturated fatty acids of sebum on the skin surface. To explain.
[0037]
The subjects were 56 women in their 20s and 30s, and after waiting for 60 minutes after washing their face in a constant temperature and humidity room, they were measured and evaluated according to the following procedures.
[0038]
Near-ultraviolet rays were irradiated to the observation target region on the skin surface of each subject's cheek, and the observation target region exhibiting a color was imaged. Of the many images obtained, four representative images (images of four subjects) with different color development states were selected. The four images selected are shown in FIG. Each image in FIG. 3 has a size of 8.0 mm × 6.2 mm as an imaging region. Each image can clearly grasp the light emission state as a bright spot in the figure, the image of FIG. 3A has no light emission point, and the image of FIG. 3B has almost no light emission point. In the image of FIG. 3C, there are some light emission points, and in the image of FIG. 3D, the light emission points are clear. In color imaging, the light emitting portion is obtained as an image exhibiting yellow to orange red coloring.
[0039]
Next, for each of the above subjects, sebum was collected from the site corresponding to the observed site on the cheek skin surface by the transfer method described in the conventional example, and free unsaturated fatty acids in the total free fatty acids in the sebum were collected. The ratio was measured using gas chromatography to obtain free unsaturated fatty acid percentage data.
[0040]
Then, the images obtained for each of the 56 subjects are classified by visual observation by several researchers and applied to the types of images shown in FIGS. 3A to 3D, and the four images described above are plotted on the horizontal axis. FIG. 4 shows the results of arrangement of the following types, with the ratio of free unsaturated fatty acids ((free) unsaturated fatty acid amount / total lipid amount) on the vertical axis.
[0041]
From FIG. 4, it can be seen that there is a significant main effect of the group with a risk rate of 1% or less between the type of the image showing the degree of the luminescent state and the free unsaturated fatty acid rate by the F test.
[0042]
A method for evaluating the percentage of free unsaturated fatty acids in sebum according to the present embodiment based on the above findings will be specifically described.
[0043]
First, irradiate the observation target areas on the skin surface of a plurality of preliminary subjects with images of the observation target areas exhibiting color development to obtain images, and release sebum from the observation target areas on the skin surfaces of the plurality of preliminary subjects. The unsaturated fatty acid ratio is evaluated by a predetermined means, and the image is associated with the evaluation result (preliminary step).
[0044]
That is, the observation target part of the skin surface, for example, a predetermined part of the face is irradiated with light by the illuminating unit 12, and the skin surface that emits fluorescence is imaged by the image acquiring unit 14 to obtain image data. On the other hand, free unsaturated fatty acid ratio data of sebum on the skin surface corresponding to each image is obtained using a technique such as chemical analysis, and the corresponding data obtained by processing by the analysis unit 18 is recorded in the recording unit 16.
[0045]
In this case, for example, the correspondence data between the image type in FIG. 4 and the free unsaturated fatty acid ratio data of sebum on the skin surface can be used as correlation data. However, in that case, more preferably, the image type is increased to, for example, 16 classifications.
[0046]
More preferably, the analysis unit 18 calculates the area (area ratio) of the light emitting portion from the image data of a plurality of preliminary subjects, and the area of the light emitting portion (area ratio) and free unsaturation of sebum on the skin surface. Correlation data with fatty acid percentage data is used.
[0047]
In these cases, after the imaged original image is subjected to image processing such as binarization in the analysis unit 18, the processed image is used, for example, by calculating the area (area ratio) of the light emitting portion. preferable.
[0048]
After passing through the above preparation steps (preliminary steps), next, the observation target region on the skin surface of the subject to be evaluated is irradiated with ultraviolet rays, and the observation target region exhibiting color development is imaged to obtain an image. The free unsaturated fatty acid ratio of sebum on the skin surface of the subject is evaluated based on the information on the correspondence (evaluation process).
[0049]
That is, the observation target part of the skin surface of the subject, for example, a predetermined part of the face is irradiated with light by the illuminating unit 12, and the skin surface that has emitted fluorescence is imaged by the image acquiring unit 14 to obtain image data. And based on this image data, with reference to the corresponding data of the recording part 16, the free unsaturated fatty acid rate of the sebum on the skin surface of the subject is calculated and evaluated.
[0050]
In this case, the handling of the image data corresponds to that in the preliminary process. That is, when the image type is adopted in the preliminary process, the image showing the light emission state (original image) is used as it is, or the processed image is processed and used on the basis of the association information obtained in the preliminary process. To evaluate the percentage of free unsaturated fatty acids in the sebum on the skin surface of the subject. On the other hand, when the area (area ratio) data of the light emitting part is adopted in the preliminary process, the area (area ratio) data of the light emitting part is calculated and used here, and the subject is based on the association information obtained in the preliminary process. The percentage of free unsaturated fatty acids in the sebum on the surface of the skin is evaluated.
[0051]
According to the method for evaluating free unsaturated fatty acid of sebum on the skin surface according to the embodiment described above, it is possible to easily and quickly evaluate the free unsaturated fatty acid on the skin surface directly on the subject's skin. it can. In addition, this makes it important for cosmetic disorders such as the degree of lipid peroxide in the skin, in other words, the degree of aging, the degree of destruction of the barrier function of the stratum corneum, in other words, the degree of rough skin, or the likelihood of makeup collapse. Factors can be evaluated.
[0052]
In addition, according to the evaluation method of free unsaturated fatty acid of sebum on the skin surface according to the present embodiment, the free unsaturated fatty acid of sebum on the skin surface can be evaluated by a simple method using a simple device, For example, it is suitable as a tool when counseling cosmetics at a cosmetic sales store or when developing cosmetics.
[0053]
In the evaluation method of the present invention, the amount of free unsaturated fatty acid (the content of free unsaturated fatty acid in the measurement sample) itself may be grasped and evaluated in place of the free unsaturated fatty acid ratio. Moreover, the evaluation method of this invention is applicable also to evaluation of sebum components other than a free unsaturated fatty acid, and in other words, can be applied to the measurement of sebum composition.
[0054]
【The invention's effect】
According to the method for evaluating the percentage of free unsaturated fatty acids in sebum according to the present invention, the observation target sites on the skin surface of a plurality of preliminary subjects are irradiated with ultraviolet rays in a state where the external light is substantially blocked, and observations exhibiting color development are observed. Preliminary step of capturing an image of a target part to obtain an image, evaluating a free unsaturated fatty acid ratio of sebum on the target part of the skin on the skin surface of a plurality of preliminary subjects by a predetermined means, and associating the result of the evaluation with the image And irradiating the observation target site on the skin surface of the subject with ultraviolet rays in a state where external light is substantially blocked, capturing an image of the observation target site exhibiting color development, obtaining an image, Evaluation of the rate of free unsaturated fatty acids in the sebum on the skin surface of the subject based on the information, so that the rate of free unsaturated fatty acids in the sebum is simply and quickly evaluated directly on the subject's skin. Can do.
[0055]
In addition, according to the method for evaluating the percentage of free unsaturated fatty acids in sebum according to the present invention, black light is used as an ultraviolet light source, and images are taken with a camera through a microscope. The ratio of free unsaturated fatty acids can be evaluated. For example, it is suitable as a tool when performing cosmetics counseling or the like at a cosmetic sales store or developing cosmetics.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of an apparatus used in a method for evaluating a rate of free unsaturated fatty acids of sebum according to an embodiment of the present invention.
2 is a diagram showing a schematic configuration of a microscope that constitutes an illumination unit of the apparatus of FIG. 1. FIG.
FIGS. 3A to 3D are images captured by the apparatus of FIG. 1 and show four images having different light emission states from those in which the light emitting portion cannot be observed to those that can be clearly observed.
FIG. 4 is a graph showing the relationship between the image types of many subjects and the percentage of free unsaturated fatty acids in sebum on the skin surface.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Apparatus 12 Illumination part 14 Image acquisition part 16 Recording part 18 Analysis part 19 Output part 20 Control part 22 Microscope 32 Black light 36 Magnification optical system 38 Color CCD element

Claims (3)

A method for evaluating the percentage of free unsaturated fatty acids in sebum for evaluating cosmetic obstacle factors,
Irradiating the observation target site on the skin surface of a plurality of preliminary subjects with ultraviolet rays, imaging the observation target site exhibiting color development to obtain an image, and the sebum of the observation target site on the skin surface of the plurality of preliminary test subjects A preliminary step of evaluating a free unsaturated fatty acid ratio by a predetermined means, and associating the result of the evaluation with the image;
Irradiating the observation target site on the subject's skin surface with ultraviolet rays, imaging the observation target site showing color development, obtaining an image, and sebum on the subject's skin surface based on the association information obtained in the preliminary step A method for evaluating the rate of free unsaturated fatty acids in sebum, comprising an evaluation step for evaluating the rate of free unsaturated fatty acids in the sebum. In the preliminary step, the image is image-processed to obtain quantification data and obtain correlation data with the result of the evaluation,
In the evaluation step, the image is subjected to image processing to obtain quantification data, and based on the correlation data, the ratio of free unsaturated fatty acids of sebum on the skin surface of the subject is quantitatively evaluated. The method for evaluating free unsaturated fatty acid of sebum according to 1.   3. The method for evaluating the ratio of free unsaturated fatty acids in sebum according to claim 1, wherein imaging is performed using a microscope equipped with black light as an ultraviolet ray source.

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