JP5826738B2 - Plate member - Google Patents

Description

  One embodiment of the present invention relates to a plate-like member used for evaluating ultraviolet transmission characteristics and / or reflection characteristics of a skin external preparation, and a method for evaluating a skin external preparation.

  Conventionally, an in vivo SPF value is used as a measure representing the ultraviolet protection effect of a skin external preparation such as a sun care product for preventing sunburn caused by ultraviolet rays. The in vivo SPF value is an index indicating the effect of protecting the skin from sunburn caused by ultraviolet rays and preventing sunburn. When using a skin external preparation, the amount of ultraviolet light necessary to cause a slight redness is determined. When not used, it is defined by the value divided by the amount of ultraviolet rays necessary to cause faint redness.

  The in vivo SPF value is obtained by irradiating the skin to which skin external preparation is not applied and the applied skin with a certain amount of ultraviolet rays using artificial light (solar simulator) that imitates some spectral characteristics of sunlight. The next day, it can be measured by examining whether sunburn (erythema) has occurred.

  If the in vivo SPF value is used, it is possible to objectively evaluate the UV protection effect of the external preparation for skin. However, in order to measure an in vivo SPF value, since cooperation of many subjects of a specific skin type is indispensable, it requires a great amount of cost and days.

  In Patent Document 1, a groove-like concave portion and a flat portion having a V-shape with a chamfered cross section are formed on one surface, and an arithmetic average roughness Sa is 10 μm or more and 50 μm or less. Is disclosed. At this time, the recess has a width of 50 μm or more and 500 μm or less and a depth of 30 μm or more and 150 μm or less. The skin substitute film has a spectral transmittance of 50% to 100% for light having a wavelength of 290 nm to 400 nm.

  However, it is desired to accurately measure the ultraviolet transmission characteristics and / or reflection characteristics of a skin external preparation having a high content of aqueous components.

WO2009 / 150883

  One embodiment of the present invention is a plate-like member capable of accurately measuring the ultraviolet transmission characteristics and / or reflection characteristics of an external preparation for skin having a high content of aqueous components, in view of the above-described problems of the prior art. The purpose is to provide.

One embodiment of the present invention is a plate-like member that is used by applying the skin external preparation when measuring the ultraviolet transmission property and / or reflection characteristic of the skin external preparation, and has a contact angle with water of 30 °. The spectral transmittance of light having a wavelength of 290 nm or more and 400 nm or less is 50% or more, the arithmetic average roughness Sa is 0.01 μm or more and 400 μm or less, and a carboxyl group or a sulfonic acid group is on the surface. Has been introduced .
Another embodiment of the present invention is a method of manufacturing a plate-like member that is used in applying the external preparation for skin in measuring the transmission characteristic and / or reflection properties of ultraviolet skin external preparation, the The plate member has a spectral transmittance of 50% or more for light having a wavelength of 290 nm to 400 nm, an arithmetic average roughness Sa of 0.01 μm to 400 μm, and a contact angle with water of 30 ° to 60 °. to be less than, and fluorine gas are front surface treated with a mixed gas containing oxygen gas or sulfur dioxide gas.

  According to one embodiment of the present invention, it is possible to provide a plate-like member capable of accurately measuring the ultraviolet transmission characteristics and / or reflection characteristics of a skin external preparation with a high content of aqueous components.

It is sectional drawing which shows an example of a plate-shaped member. It is a figure which shows an example of the evaluation apparatus of the ultraviolet-ray transmission characteristic of a skin external preparation.

  Next, the form for implementing this invention is demonstrated.

  FIG. 1 shows an example of a plate member.

  The flat plate P is used by applying the skin external preparation A when measuring the ultraviolet transmission characteristics and / or reflection characteristics of the skin external preparation A.

  The contact angle of the flat plate P with respect to water is 60 ° or less, and preferably 50 ° or less. When the contact angle of the flat plate P with respect to water exceeds 60 °, it becomes difficult to uniformly apply the skin external preparation A having a high content of aqueous components, and as a result, the ultraviolet light transmission characteristics of the skin external preparation A and It becomes difficult to accurately measure the reflection characteristics. In addition, the contact angle with respect to the water of the flat plate P is 30 degrees or more normally.

  The flat plate P is manufactured by surface-treating the flat plate with a mixed gas containing fluorine gas and oxygen gas or sulfurous acid gas. Thereby, a carboxyl group or a sulfonic acid group can be introduced into the surface of the flat plate P. Moreover, the contact angle with respect to the water of the flat plate P can be maintained for a long time.

  The spectral transmittance of light with a flat plate P having a wavelength of 290 to 400 nm is usually 50% or more and preferably 60% or more. Thereby, the ultraviolet-ray transmission characteristic and / or reflection characteristic of the external preparation A for skin can be measured accurately.

  The thickness of the flat plate P is usually 0.1 to 5.0 mm, and preferably 0.2 to 3.0 mm. If the thickness of the flat plate P is less than 0.1 mm, the plate P may be difficult to manufacture because it is brittle and easily damaged. If the thickness exceeds 5.0 mm, the wavelength of the flat plate P is 290 to 400 nm. It may be difficult to increase the spectral transmittance of the liquid crystal to 50% or more.

  The material constituting the flat plate to be surface-treated is not particularly limited as long as the spectral transmittance of light having a wavelength of 290 to 400 nm is 50% or more, but polymethyl methacrylate (PMMA), polyethylene (PE), etc. These resins are mentioned. Among them, polymethyl methacrylate (PMMA) is preferable because it is excellent in spectral transmittance of light having a wavelength of 290 to 400 nm.

  The arithmetic average roughness Sa of the flat plate P is usually 0.01 to 400 μm, and preferably 0.1 to 30 μm. When the arithmetic average roughness Sa of the flat plate P is 0.01 μm or exceeds 400 μm, the difference from the arithmetic average roughness Sa of the skin surface becomes large, so the ultraviolet rays of the skin external preparation A in vivo. It may be difficult to reproduce the conditions when evaluating the transmission characteristics and / or reflection characteristics of the film.

  In addition, as for the flat plate P, arithmetic mean roughness Sa of one side is 0.01-400 micrometers normally, However, 0.01-400 micrometers of arithmetic mean roughness Sa of both surfaces may be sufficient.

  The arithmetic average roughness Sa is obtained by extending the two-dimensional arithmetic average roughness Ra to three dimensions, and dividing the volume of the portion surrounded by the surface shape curved surface and the average surface by the measurement area. When the average plane is the xy plane, the vertical direction is the z axis, and the measured surface shape curve is z = f (x, y), the formula

（式中、Ｌ_ｘは、ｘ方向の測定長であり、Ｌ_ｙは、ｙ方向の測定長である。）
で定義される。

(In the formula, L _x is the measurement length in the x direction, and L _y is the measurement length in the y direction.)
Defined by

  The method of imparting roughness to the surface of the flat plate is not particularly limited, and examples thereof include a method of sandblasting the flat plate, a method of molding the flat plate, a method of laser processing the flat plate, and the like. Good.

  Examples of commercially available PMMA flat plates used for sandblasting include Sumipex 010 (manufactured by Sumitomo Chemical Co., Ltd.), Paragrass UV00 (manufactured by Kuraray Co., Ltd.), Acrylite 000 (manufactured by Mitsubishi Rayon Co., Ltd.), and the like.

  As a commercial product of PMMA used for molding, Acripet VH000 (manufactured by Mitsubishi Rayon Co., Ltd.) and the like can be mentioned.

  The material constituting the mold used for molding is not particularly limited; however, metals such as aluminum, nickel and copper; resins such as acrylic resins and epoxy resins; mixtures of metal powders and resins (metal resins), etc. Is mentioned.

  The mold can be manufactured using a master manufactured by machining or the like.

  Although it does not specifically limit as a material which comprises a master, Metals, such as aluminum, nickel, copper; Resins, such as an acrylic resin and an epoxy resin; Mixtures (metal resin) of metal powder and resin, etc. are mentioned.

  The method for imparting roughness to the surface of the mold is not particularly limited, and examples thereof include a method of transferring a master that has been sandblasted, a method of sandblasting the mold, and the like.

  The temperature at which the flat plate P is surface-treated with a mixed gas is usually 0 to 60 ° C, preferably 10 to 35 ° C. If the temperature at which the surface treatment of the flat plate P is performed with a mixed gas is less than 0 ° C, it may not be possible to sufficiently introduce carboxyl groups or sulfonic acid groups to the surface of the flat plate P. May be fluorinated.

  The time for surface treatment of the flat plate P with the mixed gas is usually 1 s to 8 h, and preferably 0.1 to 60 min.

  The time for surface treatment of the flat plate P with the mixed gas can be adjusted by the partial pressure of the fluorine gas.

  The partial pressure of the fluorine gas when surface-treating the flat plate P with a mixed gas is usually 0.1 to 50 kPa, and preferably 1 to 20 kPa.

  The partial pressure of the oxygen gas when the plate P is surface-treated with a mixed gas is usually 0.2 to 100 kPa, and preferably 2 to 100 kPa.

  At this time, the ratio of the partial pressure of oxygen gas to the partial pressure of fluorine gas is usually 2 or more. If the ratio of the partial pressure of oxygen gas to the partial pressure of fluorine gas is less than 2, the surface of the flat plate P may be fluorinated.

  In addition, when the surface treatment of the flat plate P is performed with a mixed gas, usually, fluorine gas and oxygen gas or sulfurous acid gas are simultaneously introduced. Alternatively, fluorine gas and oxygen gas or sulfurous acid gas may be alternately introduced to form a mixed gas. Good.

  The mixed gas may further contain an inert gas such as nitrogen gas or argon gas.

  Furthermore, the flat plate surface-treated with the mixed gas may be washed or neutralized using water, warm water, an alkaline aqueous solution, or the like.

  Although it does not specifically limit as skin external preparation A, Sunscreen cosmetics, makeup cosmetics, skin care cosmetics, pre-makeup cosmetics, body cosmetics, etc. are mentioned.

  Although it does not specifically limit as a form of the skin external preparation A, An emulsion, lotion, solid, oil, spray, etc. are mentioned.

  The method for evaluating skin external preparation A includes the steps of applying skin external preparation A to flat plate P, and the ultraviolet light transmission characteristics of skin external preparation A by irradiating light containing ultraviolet rays onto flat plate P applied with skin external preparation A. And / or measuring reflection characteristics.

  The method of applying the external preparation for skin to the flat plate P is not particularly limited, but there are a method of applying with a finger, a method of applying with a finger with a finger sack, etc., in accordance with the rules for measuring SPF etc. in vivo. Can be mentioned.

  The evaluation device for the ultraviolet transmission property and / or reflection property of the external preparation A for skin is not particularly limited, but an evaluation device disclosed in JP2008-96151A, JP2008-1111834A, or the like is used. be able to.

  In FIG. 2, an example of the evaluation apparatus of the ultraviolet transmission characteristic of the external preparation A for skin is shown.

  The evaluation apparatus 10 includes a light source 11, a filter 12, an optical chopper 13, an optical fiber 14, an irradiation port 15, an integrating sphere 16, a detection port 17, an optical fiber 18, a spectrometer 19, a photodetector 20, a lock-in amplifier 21, and a computer. Machine 22. At this time, the flat plate P to which the external preparation A for skin is applied is disposed between the irradiation port 15 and the integrating sphere 16, but is disposed on a flat plate of quartz or the like having excellent ultraviolet transmission characteristics as necessary. May be.

  Although it does not specifically limit as the light source 11, The xenon lamp etc. which are light sources of white light containing an ultraviolet-ray, visible light, and infrared rays can be used.

  In addition, the white light irradiated from a xenon lamp can be used as pseudo sunlight.

  The filter 12 is in the vicinity of the traveling direction of the light emitted from the light source 11, corrects the light emitted from the light source 11 to ultraviolet rays (for example, ultraviolet rays having a wavelength of 290 to 400 nm), and passes through the filter 12. Is irradiated to the light chopper 23.

  Although it does not specifically limit as the filter 12, WG320, UG11 (above, the product made by SCHOTT) etc. are mentioned.

  The optical chopper 13 is a shutter that intermittently transmits the ultraviolet rays that have passed through the filter 12, and irradiates the ultraviolet rays in pulses. The ultraviolet light irradiated with the pulse by the optical chopper 13 is irradiated to the optical fiber 14.

  The optical fiber 14 is disposed in the vicinity of the traveling direction of the ultraviolet light pulsed by the optical chopper 13 and guides the ultraviolet light to the irradiation port 15. The ultraviolet light guided to the irradiation port 15 by the optical fiber 14 is irradiated to the flat plate P on which the skin external preparation A is applied.

  The detection port 17 is fixed at a predetermined distance from the irradiation port 15, and the flat plate P coated with the external preparation for skin A is fixed at a certain distance from the irradiation port 15. At this time, the irradiation port 15, the external preparation A for skin, the flat plate P, and the integrating sphere 16 are sequentially arranged with respect to the traveling direction of the ultraviolet rays.

  The integrating sphere 16 receives the ultraviolet rays transmitted through the external preparation A for skin and the flat plate P, collects it, and integrates it spatially to make it uniform.

  Note that the integrating sphere 16 can be omitted.

  The detection port 17 receives the ultraviolet light made uniform by the integrating sphere 16 and guides it to the optical fiber 18.

  The optical fiber 18 is in the vicinity of the traveling direction of the ultraviolet light emitted from the detection port 17 and guides the ultraviolet light received by the detection port 17 to the spectrometer 19.

  The spectroscope 19 separates the ultraviolet rays irradiated from the optical fiber 18 (for example, in a wavelength range of 290 to 400 nm) at 1 nm intervals. The ultraviolet rays dispersed by the spectroscope 19 are applied to the photodetector 20.

  As the spectroscope 19, by using a diffraction grating having excellent sensitivity characteristics to ultraviolet rays (for example, a diffraction grating having excellent sensitivity characteristics to ultraviolet rays having a wavelength of 290 to 400 nm), the spectral performance can be made high sensitivity.

  Although it does not specifically limit as a diffraction grating, A concave-surface diffraction grating (model number 10-015) (made by Shimadzu Corporation Corp.) etc. are mentioned.

  The light detector 20 detects the ultraviolet rays separated by the spectroscope 19 with an optical sensor, and converts the intensity of the ultraviolet rays of the respective wavelengths into signals. The signal converted by the photodetector 20 is transmitted to a computer 22 connected by wiring via a lock-in amplifier 21.

  As the photodetector 20, a photomultiplier tube having excellent sensitivity characteristics with respect to ultraviolet rays (for example, a photomultiplier tube having excellent sensitivity characteristics with respect to ultraviolet rays having a wavelength of 290 to 400 nm) is used to improve the sensitivity of detecting ultraviolet rays. be able to.

  Although it does not specifically limit as a photomultiplier tube, What has a photocathode (for example, InGaN photocathode) containing In, Ga, N, Al, O, Cs etc. is mentioned.

  As the photodetector 20, a semiconductor photodetector including In, Ga, N, Al, O, or the like may be used.

  The lock-in amplifier 21 is connected to the photodetector 20, the computer 22, and the optical chopper 13 by wiring. The lock-in amplifier 21 is controlled so as to acquire the synchronization signal of the ultraviolet light pulsed by the optical chopper 13 and perform the synchronous analysis of the signal converted by the photodetector 20. Specifically, the two signals are synchronized using a phase detection circuit in the lock-in amplifier 21.

  The computer 22 receives the data that has been synchronously analyzed by the lock-in amplifier 21, processes the data so as to be easily understood by the user, displays the result on the screen, puts the result on a recording sheet, and stores the result. Or save to media.

  As the computer 22, a general-purpose personal computer or the like can be used, and each function of the evaluation apparatus 10 can be executed in accordance with an instruction from the user by an input means or the like.

  Although there is no particular limitation on the method for evaluating the ultraviolet transmission property of the external preparation for skin, the in vitro SPF evaluation method disclosed in Japanese Patent No. 3337832, Japanese Patent Application Laid-Open No. 2008-1111834, or the like can be used. Thereby, an in vitro SPF predicted value can be measured.

  Moreover, as an evaluation method of the ultraviolet transmission property and / or reflection property of the external preparation for skin other than the in vitro SPF evaluation method, an in vitro UVA evaluation method, an in vitro PPD method, an in vitro PFA method, an in vitro UVAPF method, a Critical Wavelength method, UVA / UVB ratio method, Australian / New Zealand method, German DIN UVA balance method, SPF / UVAPF (PPD) ratio method and the like may be used (Ferrero L. et al.,). Importance of Substrate Roughness for In Vitro Sun Protection Assessment, IFSCC Magazine, ol.9, reference No.2,2-13 (2006)).

  In addition, after apply | coating a skin external preparation, the flat plate P can also be used when evaluating the uniformity of application | coating of a skin external preparation by irradiating light, such as an ultraviolet-ray and visible light.

  In this case, the flat plate P does not need to have a spectral transmittance of 50% or more for light having a wavelength of 290 to 400 nm. For this reason, as a material constituting the flat plate to be surface-treated, it is possible to perform surface treatment with a mixed gas containing fluorine gas and oxygen gas or sulfurous acid gas so that the contact angle with water becomes 30 to 60 °. If there is no particular limitation, polyethylene, polypropylene, polyvinyl chloride, ABS resin, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, nylon, polyetheretherketone, polyimide, polyphenylene sulfide, natural rubber, chloroprene rubber, Examples thereof include resins such as nitrile rubber, ethylene propylene rubber, and cycloolefin polymer.

[Example 1]
In the F Technical Support Center facility (manufactured by Takamatsu Teikoku Co., Ltd.), using a mixed gas of fluorine gas and oxygen gas, the arithmetic average roughness Sa is 2 μm, the contact angle with water is 70 °, and the thickness is 2 mm. Was subjected to surface treatment at 60 ° C. for 60 minutes to obtain a flat plate having a contact angle with water of 45 °. At this time, the partial pressure of fluorine gas was 7 kPa, and the partial pressure of oxygen gas was 83 kPa.

[Example 2]
A flat plate having a contact angle with respect to water of 45 ° was obtained in the same manner as in Example 1 except that a flat plate made of PMMA having an arithmetic average roughness Sa of 6 μm, a contact angle with respect to water of 70 °, and a thickness of 1 mm was used. It was.

[Example 3]
A flat plate having a contact angle with respect to water of 45 ° was obtained in the same manner as in Example 1 except that a flat plate made of PMMA having an arithmetic average roughness Sa of 17 μm, a contact angle with respect to water of 70 °, and a thickness of 1 mm was used. It was.

[Example 4]
A flat plate having a contact angle with respect to water of 45 ° was obtained in the same manner as in Example 1 except that a flat plate made of PMMA having an arithmetic average roughness Sa of 30 μm, a contact angle with respect to water of 70 °, and a thickness of 1 mm was used. It was.

[Example 5]
The contact angle with respect to water was 60 ° in the same manner as in Example 3 except that the temperature was changed to 25 ° C., the treatment time was changed to 10 minutes, the partial pressure of fluorine gas was changed to 1 kPa, and the partial pressure of oxygen gas was changed to 89 kPa. A flat plate was obtained.

[Example 6]
A flat plate having a water contact angle of 30 ° was obtained in the same manner as in Example 3 except that the temperature was changed to 25 ° C and the treatment time was changed to 60 minutes.

[Comparative Example 1]
A PMMA flat plate having an arithmetic average roughness Sa of 17 μm, a contact angle with water of 70 °, and a thickness of 1 mm was used as it was without surface treatment.

[Comparative Example 2]
Using a corona discharge treatment device Corona Master PS-1M (manufactured by Shinko Electric Instrumentation Co., Ltd.), a plate made of PMMA having an arithmetic average roughness Sa of 17 μm, a contact angle with water of 70 °, and a thickness of 1 mm at 15 kV is 15 Surface treatment was performed for 2 seconds to obtain a flat plate having a contact angle with water of 65 °.

[Comparative Example 3]
A flat plate having a contact angle with water of 60 ° was obtained in the same manner as in Comparative Example 2 except that the surface treatment was performed at 10 kV for 30 seconds.

[Comparative Example 4]
A flat plate having a contact angle with water of 45 ° was obtained in the same manner as in Comparative Example 2 except that the surface treatment was performed at 15 kV for 1 minute.

[Comparative Example 5]
A flat plate having a contact angle with water of 30 ° was obtained in the same manner as in Comparative Example 2 except that the surface treatment was performed at 15 kV for 2 minutes.

<Contact angle to water>
Under the condition of 25 ° C., using an automatic contact angle measuring device DM-501 (manufactured by Kyowa Interface Chemical Co., Ltd.), after measuring 3.0 μL of pure water, the contact angle after 60 seconds was measured at 5 locations. The average value was obtained.

<Contact angle for water after one month>
One month after measuring the contact angle with water, the contact angle with water was determined in the same manner as described above.

[Preparation of external preparation A for skin]
As ultraviolet absorber, Octyl methoxycinnamate, Bisethylhexylphenol methenylphenyl triazine, Butyl methoxy dibenzethane, and octocycle are contained in water. An external preparation A was obtained.

[Preparation of external preparation for skin B]
As an ultraviolet absorber, Phenylbenzimidazole sulphonic acid, Polysilicone-15, Butylmethydibenzoylmethane, Octocyclene is blended, and the content of the water-based component (other than oil) is set to v to be 71.5% by weight. Skin external preparation B was obtained.

<In vivo SPF value>
The in vivo SPF value of the external preparation for skin was measured according to ISO 24444, COSMETICS-SUN protection test methods-In vivo determination of the sun protection factor (SPF).

<Uniform application of external preparation for skin>
By applying the evaluation method of variation in the coated surface described in WO2010 / 113396, a CV value of variation in the coated surface by a simple in vitro SPF value was obtained, and coating uniformity was evaluated.

  Here, the CV value is a value obtained by dividing the standard deviation by the average value. In addition, as described later, the simple in vitro SPF value simply reduces the UV protection ability from the ratio of the erythema effect amount when the skin external preparation is applied to the erythema effect amount when the skin external preparation is not applied. It is a numerical value calculated automatically and is different from the in vivo SPF value in that it does not reflect the photodegradation phenomenon of the external preparation for skin.

  Specifically, first, in accordance with the method described in ISO 24444 In vivo SPF, the evaluation specialist uses the fingers to apply the external skin preparation A and the external skin preparation B to the three 50 mm long and 50 mm wide flat plates. Applied. Next, a spectral transmission spectrum with a wavelength of 290 to 400 nm was measured using a spectrophotometer U-4100 (manufactured by Hitachi, Ltd.). At this time, the wavelength step was set to 1 nm. Moreover, the measurement location of the spectral transmission spectrum was 1 center and 4 locations in the vicinity of the middle point connecting the center and the four corners as in the 5th of the dice, and the number of measurements was once per location. Furthermore, the spectrum of the xenon arc ultraviolet light source described in ISO 24444 In vivo SPF is multiplied by the spectral transmittance of the spectral transmission spectrum having a wavelength of 290 to 400 nm, and the erythema action curve weighted by the erythema coefficient (see CIE-1987) is obtained. The erythema effect amount was determined by integrating with the wavelength. Moreover, the simple in vitro SPF was calculated by dividing the erythema effect amount when the skin external preparation was not applied by the erythema effect amount when the skin external application was applied, and the average value was obtained. Furthermore, CV value was calculated | required from the average value and standard deviation in three flat plates of the average value of simple in vitro SPF value.

  The application uniformity of the external preparation for skin was judged as ◯ when the CV value was less than 15%, Δ when it was 15% or more and less than 20%, and x when it was 20% or more.

<Degree of agreement of SPF value of external preparation for skin>
First, in accordance with the method described in ISO 24444 In vivo SPF, the evaluation specialist applied the skin external preparation A and the skin external preparation B with fingers on three plates each having a length of 50 mm and a width of 50 mm. Next, a spectral transmission spectrum having a wavelength of 290 to 400 nm was measured using an in vitro SPF evaluation apparatus SPFMASTER (manufactured by Shiseido Medical Rika Technology Co., Ltd.). At this time, the wavelength step was set to 1 nm. Moreover, the measurement location of the spectral transmission spectrum was 1 location (center portion), and the number of measurements was 1 time. Furthermore, based on the evaluation algorithm, the in vitro SPF value was calculated, and the average value of the three flat plates was obtained. Similar to the in vivo SPF value, the evaluation algorithm is an algorithm having 1 MED (minimum erythema amount) as an evaluation endpoint by integrating the transmitted ultraviolet light with time while continuously irradiating the ultraviolet light.

  In addition, the agreement degree of the SPF value of the external preparation for skin is ◯ when the average value of the in vitro SPF value divided by the in vivo SPF value is 0.75 or more and less than 1.25, 0.50 or more and 0.00. The case of less than 75, or 1.25 or more and less than 1.50 was judged as Δ, less than 0.50, or 1.50 or more as x.

  In Table 1, the evaluation result of the flat plate of an Example and a comparative example is shown.

表１から、実施例１〜６の平板は、皮膚外用剤Ａ及び皮膚外用剤Ｂを均一に塗布でき、皮膚外用剤Ａ及び皮膚外用剤Ｂのｉｎ ｖｉｖｏ ＳＰＦ値を精度良く測定できることがわかる。また、実施例１〜６の平板は、水に対する接触角を長期間維持できることがわかる。

From Table 1, it can be seen that the flat plates of Examples 1 to 6 can uniformly apply the skin external preparation A and the skin external preparation B, and can accurately measure the in vivo SPF values of the skin external preparation A and the skin external preparation B. Moreover, it turns out that the flat plate of Examples 1-6 can maintain the contact angle with respect to water for a long period of time.

  On the other hand, since the flat plates of Comparative Examples 1 and 2 have a contact angle with water of 65 to 70 °, the skin external preparation A and the skin external preparation B cannot be uniformly applied. In addition, the in vivo SPF value of the external preparation for skin B cannot be measured with high accuracy.

  Moreover, since the flat plates of Comparative Examples 2 to 5 are subjected to corona treatment, the contact angle with water cannot be maintained for a long time.

A Skin preparation P Plate

Claims (4)

A plate-like member used by applying the external preparation for skin when measuring the ultraviolet transmission and / or reflection characteristics of the external preparation for skin,
The contact angle with water is 30 ° or more and 60 ° or less,
The spectral transmittance of light having a wavelength of 290 nm or more and 400 nm or less is 50% or more,
Arithmetic mean roughness Sa is 0.01 μm or more and 400 μm or less,
A plate-like member, wherein a carboxyl group or a sulfonic acid group is introduced on the surface . Plate member according to claim 1, wherein the early days including polymethyl methacrylate. A method for producing a plate-like member to be used by applying the external preparation for skin when measuring the ultraviolet transmission and / or reflection characteristics of the external preparation for skin,
The plate member has a spectral transmittance of 50% or more for light having a wavelength of 290 nm or more and 400 nm or less, and an arithmetic average roughness Sa of 0.01 μm or more and 400 μm or less,
As contact angle to water is 30 ° to 60 °, the manufacturing method of the plate-like member, characterized in that the fluorine gas, a mixed gas containing oxygen gas or sulfurous acid gas is processed front surface. Applying a skin external preparation to the plate-like member according to claim 1 or 2 ,
Evaluation of a skin external preparation characterized by comprising a step of irradiating a plate-like member coated with the external preparation for skin with light containing ultraviolet rays and measuring the ultraviolet transmission characteristics and / or reflection characteristics of the external preparation for skin. Method.

Images