Measurement method for determining protection factor and protection factor evaluation system

Abstract

The invention describes a method for determining a protection factor, the method comprising a spectral measurement having the following method steps: emitting radiation from a beam source, the emitted radiation comprising light at a radiation wavelength between 280 nm and 2000 nm; irradiating the measurement body with the emitted radiation; detecting radiation diffusely reflected by the irradiated measurement body at a detection wavelength; a protection factor of the protection means is evaluated from the diffusely reflected radiation and the transmission spectrum at an evaluation wavelength, the data of the transmission spectrum being used to evaluate the protection factor of the protection means, the evaluation wavelength being different from the wavelength range of the radiation wavelength and / or the detection wavelength, and the data of the transmission spectrum being electronic data. The invention also describes an SPF evaluation system for checking a protection factor of a protection means, comprising the following components: a measuring device having a light beam source arrangement comprising a light beam source, a detector unit; a control unit for controlling the measuring device; and an evaluation unit.

Description

[0001] The present invention relates to a method for determining a protection factor, the method comprising the following method steps: emitting radiation from a light beam source, wherein the emitted radiation comprises light at radiation wavelengths between 280 nm and 2000 nm; irradiating a measurement subject with the emitted radiation; detecting, at a detection wavelength, the radiation diffusely reflected by the irradiated measurement subject; evaluating, at an evaluation wavelength, the protection factor of a protection means based on the diffusely reflected radiation and a transmission spectrum, wherein data of the transmission spectrum is used to evaluate the protection factor of the protection means, wherein the evaluation wavelength is different from the wavelength range of the radiation wavelength and / or the detection wavelength, and wherein the data of the transmission spectrum is electronic data. The present invention also describes an SPF evaluation system for checking the protection factor of a protection means, which comprises the following components: a measuring device having a light beam source device and a detector unit, the light beam source device comprising a light beam source; a control unit for controlling the measuring device; and an evaluation unit. Prior art

[0002] Previously approved by the European Union (EU) and US Food and Drug Administration (FDA) authorities for determining the sun protection factor (SPF), the protection methods are harmful to the test subjects involved by causing erythema (i.e., a light-induced skin inflammatory response) (COLIPA-15 European Cosmetics, Toiletries and Perfumery Association: Colipa SPF Test Method 94 / 289, 1994; ISO standards 24442, 24443, 24444). Therefore, both the FDA and the EU have repeatedly stated that future research activities must focus on new methods for characterizing the protection efficacy of sunscreen products to avoid long-term effects on test subjects (European Commission, Standardisation Mandate Assigned To CEN Concerning Methods For Testing Efficacy Of Sunscreen Products, M / 389EN, Brussels, July 12, 2006).

[0003] The present invention aims to achieve this purpose. Existing procedures are defined in various sources:

[0004] Procedures are defined in standards and regulations:

[0005] a. ISO 24444 defines a method for in vivo determination of SPF. The method is based on the fact that radiation in the UVB range produces erythema on the skin of the test subject. Therefore, the method is harmful to the test subject.

[0006] b. ISO 24443 defines a method for the in vitro determination of the UVA protection factor (UVAPF). The protection means is applied to a plastic plate so that the transmission spectrum of the protection means can be measured. Due to uncontrollable fluctuations in the procedure, the transmission spectrum is scaled to match the results of the erythema test in accordance with ISO 24444 and thus depends on its implementation. The plastic plate used has a rough surface and is an unrealistic skin model.

[0007] c. ISO 24442 defines an in vivo method in which the UVA protection factor is determined using the minimum UVA dose required to produce irreversible skin pigmentation (tanning). This method also causes changes to the skin of the test subject.

[0008] Patented methods:

[0009] DE 198 28 497 A1 describes a method in which, as in ISO 24444, erythema is induced in a test subject by UV irradiation of the skin. Compared with ISO 24444, erythema is detected by reflectance spectrometry. Therefore, this method is also harmful. The optical effect (protective action) of the protection means is not recorded by direct optical measurement, but by the biological reaction of the body.

[0010] DE 10 2004 020 644 A1 describes a method in which electron spin resonance (ESR) is used to quantitatively measure free radicals generated in vivo by UV exposure. Here, the optical effect of the protection means is also only indirectly recorded. In addition, measuring ESR is technically complex and requires a relatively large fixture (bench-top device). They are also sensitive to interference from high-frequency radiation or rapid transient magnetic field changes (such as those caused by an electrical switching process).

[0011] To determine the labeled SPF of a topically applied protection means in vivo, test methods such as ISO 24444, FDA guidelines or Australian standards are used worldwide. The basis of all these methods is to induce an erythemal skin reaction by irradiating the skin with UV light. This is necessary to determine the minimum erythema dose of untreated skin (MEDu) and product-treated skin (MEDp). A reliable in vitro method using a synthetic substrate carrier to replace human skin cannot be used for SPF determination.

[0012] It is well known that monochromatic devices use conventional xenon lamps and are therefore expensive to purchase and operate. The built-in monochromator measures different wavelengths in sequence, which is disadvantageous when the test object is moving. Multichromatic devices also use xenon lamps. Filters are used to weight the measured values in vivo such that the measured values in vivo match the in vivo UVA PF. The multi-LED device for the test mechanism represents another variant, however, due to spectral detection, it is larger in size and higher in cost.

[0013] Accordingly, it is an object of the present invention to provide a method for determining a protection factor, which method can reduce the radiation exposure of human skin, which method provides high-quality analysis results and can be carried out quickly and easily at the same time.

[0014] It is also an object of the present invention to provide an SPF evaluation system for evaluating the protection factor of a protection means, which SPF evaluation system provides high-quality analysis results, reduces the radiation exposure of human skin, and is low in manufacturing and operating costs.

[0015] The object is achieved by a method for determining a protection factor according to the present invention. Advantageous embodiments of the present invention are set forth in the dependent claims below.

[0016] The method for determining a protection factor according to the present invention (including spectral measurement) has four method steps: In the first method step, radiation is emitted from a beam source, wherein the emitted radiation includes light at radiation wavelengths in the range between 280 nm and 2000 nm, preferably from 280 nm to 800 nm, particularly preferably from 280 nm to 500 nm. In the context of this document, a beam source is a technical device for generating electromagnetic radiation. Therefore, a beam source is not an optical element for guiding, deflecting or changing the intensity and / or wavelength of electromagnetic radiation. Therefore, a beam source is not, for example, an optical fiber, a grating, a prism or a filter. The beam source generates electromagnetic radiation at radiation wavelengths between the blue spectral range (from about 400 nm to 500 nm wavelength) and the UV range (280 nm to 400 nm).

[0017] The wavelength ranges are defined as follows:

[0018] - <320 nm (UVB), which accounts for <0.1% of the total UV intensity,

[0019] - 320 nm to 340 nm (UVA II), accounting for 8% to 20% of the total UVA intensity,

[0020] - 340 nm to 400 nm (UVA I), accounting for 80% to 92% of the total UVA intensity,

[0021] - 400 nm to 500 nm, blue light.

[0022] Preferably, the radiation wavelength covers a wavelength range between 280 nm and 500 nm.

[0023] In the second method step, the measurement object is irradiated with the emitted radiation. In the case of in-vivo measurement, the measurement object is the human skin covering the protection means to be tested; in the case of in-vitro measurement, the measurement object is a standardized test object covering the protection means to be tested.

[0024] In the third method step, the diffusely reflected radiation of the irradiated measurement object is detected at a detection wavelength. The ratio of the intensity of the diffusely reflected radiation to the intensity of the radiation coupled into the measurement object is a measure of the protection ability of the protection means component. Similar to the radiation wavelength, the detection wavelength preferably includes a wavelength range, where the wavelength range of the detection wavelength is preferably located within the radiation wavelength range or includes the entire radiation wavelength range. Therefore, the spectral measurement particularly includes recording the diffusely reflected spectrum I(λ) (diffuse backscattering).

[0025] In the fourth step of the method, an evaluation wavelength is used to evaluate the protection factor of the protection means based on the diffusely reflected radiation and the transmission spectrum, where the data of the transmission spectrum is used to evaluate the protection factor of the protection means. The transmission spectrum is determined based on the UV transmittance of the in-vitro protection film. The substrate applied to the protection film only approximately replicates the inhomogeneous surface structure of the human skin, such as a polymethyl methacrylate (PMMA) sheet with a rough surface according to ISO 24443. The transmission spectrum data preferably includes the ratio of intensity to wavelength in a digital format.

[0026] The evaluation wavelength is the wavelength at which the protection factor is determined. The evaluation wavelength is different from the wavelength ranges of the radiation wavelength and / or the detection wavelength. Similar to the radiation wavelength and the detection wavelength, the evaluation wavelength is preferably a wavelength range, where the wavelength range of the evaluation wavelength at least includes the wavelength ranges of the radiation wavelength and / or the detection wavelength.

[0027] Advantageously, the transmission spectrum data is electronic data. Therefore, the data of the transmission spectrum is neither measured in the test object in vivo nor determined in vitro according to ISO 24443, but is estimated or measured by a mathematical method. If the properties of the filter material of the protection means are known, the transmittance can be calculated and simulated. Based on the simulated transmittance, the sun protection factor and all parameters characterizing the sun protection factor can be calculated.

[0028] The Sun Protection Factor (SPF) is a scientific measure and indicates how much the risk of skin damage is reduced when using a protective means. This factor focuses on comparing the time required for UVB rays to penetrate the protective means and cause skin redness (minimal erythema, MED) with the time required in the absence of the protective means. The dose of solar radiation required to cause skin redness is divided by the dose required to cause skin redness without the protective means. This calculation is based on using 2 milligrams of the protective agent per square centimeter of skin surface. Currently, the SPF value of a protective means is determined by in vivo irradiation using a solar simulator (ISO 24444:2010 "Cosmetics - Methods for sun protection testing - In vivo determination of the sun protection factor (SPF)"), which represents the current state of the art. The current basis for testing protective means is that the subject is irradiated before and after applying the protective means.

[0029] The advantages of the method according to the invention also lie particularly in that the electronic data do not represent a standard and can currently only be used for estimation. However, with the method according to the invention, the deviation between the estimated value and the actual data is significantly improved.

[0030] In a further development of the invention, the wavelength range of the transmission spectrum includes the evaluation wavelength. The evaluation of the sun protection factor of a protective means is based on in vivo diffuse reflectance radiation and electronic transmission spectra. Due to its high absorption properties, human skin does not emit enough UVB radiation to measure the absorption spectrum of the applied product in the UVB range. Therefore, it is necessary to use different techniques to separately record the absorption spectrum of the test material in the UVB part (280 nm to 320 nm) of the spectrum. The method employed in this document is to perform in vivo evaluation using the absolute UVA absorption spectrum measured by in vivo measurement, where the calculated electronic transmission spectrum is used to determine the sun protection factor of the protective means for the user. The in vivo remission spectrum and the electronic transmission spectrum are evaluated and combined to obtain a complete UV spectrum, enabling the calculation of the sun protection factor according to the equation of the applicable standard (ISO 24443). For this purpose, the wavelength range of the transmission spectrum includes the evaluation wavelength, which preferably covers the range from 280 nm to 500 nm.

[0031] In a further embodiment of the invention, the evaluation wavelength includes a wavelength range from 280 nm to 2000 nm, preferably a wavelength range from 280 nm to 800 nm, or particularly preferably a wavelength range from 280 nm to 500 nm. In a further development, the evaluation wavelength covers the wavelength range from 400 nm to 500 nm, and preferably the wavelength range from 400 nm to 450 nm. The blue light wavelength range in the approximate UVA range (up to 400 nm) is preferably evaluated. In order to determine the protection ability of the protective means in the UVB wavelength range (<320 nm), this wavelength range can also be optionally evaluated.

[0032] In yet another embodiment of the present invention, the evaluation of the protection ability of the protection means against light in the wavelength range from 400 nm to 500 nm and the evaluation of the protection ability against light in the wavelength range from 280 nm to 400 nm are carried out in separate processes. Due to its high absorption property, human skin does not emit sufficient UVB radiation to measure the absorption spectrum of the applied product in the UVB range. Therefore, it is necessary to use different techniques to separately record the absorption spectrum of the test material in the UVB part (280 nm to 320 nm) of the spectrum. For this purpose, in vivo remission spectra in the wavelength range from 320 nm to 400 nm, from 280 nm to 320 nm, and from 400 nm to 500 nm are recorded using electronic transmission spectroscopy.

[0033] In yet another embodiment of the present invention, the evaluation of the protection ability of the protection means against light in the wavelength range from 400 nm to 500 nm and the evaluation of the protection ability against light in the wavelength range from 280 nm to 400 nm are carried out in different processes. Due to its high absorption property, human skin does not emit sufficient UVB radiation to measure the absorption spectrum of the applied product in the UVB range. Therefore, it is necessary to use different techniques to separately record the absorption spectrum of the test material in the UVB part (280 nm to 320 nm) of the spectrum. For this purpose, in vivo remission spectra in the wavelength range from 320 nm to 400 nm, from 280 nm to 320 nm, and from 400 nm to 500 nm are recorded using electronic transmission spectroscopy.

[0034] In yet another embodiment of the present invention, the wavelength range of the radiation wavelength or the wavelength range of the detection wavelength is less than the wavelength range of the evaluation wavelength. The wavelength ranges of the radiation wavelength and the detection wavelength are preferably the same in the wavelength range from 320 nm to 400 nm at most. The wavelength range of the evaluation wavelength covers the maximum range from 280 nm to 500 nm.

[0035] In yet another embodiment of the present invention, the wavelength range of the radiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is less than the wavelength range of the evaluation wavelength. The wavelength ranges of the radiation wavelength and the detection wavelength are preferably equal, both in the wavelength range from 320 nm to 400 nm, where the wavelength ranges of the radiation wavelength and the detection wavelength are less than the wavelength range from 320 nm to 400 nm. In the wavelength range of the evaluation wavelength (maximum 280 nm to 500 nm), the wavelength range of the radiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is less than the wavelength range of the evaluation wavelength.

[0036] In a further development of the present invention, the wavelength range of the radiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm. Thus, only one steel source is required to emit electromagnetic radiation with a very narrow wavelength range of the radiation wavelength. Similarly, for recording the reflection spectrum, a detector capable of detecting a small wavelength range of the detection wavelength is required. Thus, the design of the light beam source and the detector is cost-effective both in manufacturing and operation.

[0037] In a further embodiment of the present invention, the radiation wavelength and / or the detection wavelength only includes light with a wavelength outside the wavelength range of 400 nm to 450 nm. For recording in-vivo measurements, it is necessary to couple the UVA wavelength range (320 nm to 400 nm) into the measurement subject.

[0038] In a further embodiment of the present invention, the radiation wavelength and / or the detection wavelength only includes light with a wavelength outside the wavelength range of 400 nm to 500 nm. Specifically, UVA and UVB in this wavelength range are irradiated. This wavelength range is the most harmful to human skin, so it is particularly important to determine the protective ability of the protection means.

[0039] In a further embodiment of the present invention, the evaluation wavelength includes wavelengths outside the wavelength range of 400 nm to 500 nm. Specifically, UVA and UVB in this wavelength range are irradiated. This wavelength range is the most harmful to human skin, so it is particularly important to determine the protective ability of the protection means.

[0040] In a further embodiment of the present invention, the evaluation wavelength includes a wavelength λ, where λ < 400 nm. For recording in-vivo measurements, it is necessary to specifically evaluate the UVA wavelength range (320 nm to 400 nm).

[0041] In a further embodiment of the present invention, the evaluation wavelength includes a wavelength λ, where 320 nm < λ < 400 nm. For recording in-vivo measurements to determine the protective ability of the protection means, the UVA wavelength range (320 nm to 400 nm) is specifically evaluated. To determine the protective ability of the protection means in the UVB wavelength range (< 320 nm), this wavelength range can also be optionally evaluated.

[0042] In yet another embodiment, radiation is emitted from a single light source, wherein the radiation emitted from one light source includes light in the wavelength range between 280 nm and 500 nm. In the context of this document, a light source is a technical device for generating electromagnetic radiation. Thus, a light source is not an optical element for guiding, deflecting, or changing the intensity and / or wavelength of electromagnetic radiation. Thus, a light source is not, for example, an optical fiber, a grating, a prism, or a filter. The light source generates electromagnetic radiation in the wavelength range within the blue spectral range (from approximately 400 nm to 500 nm wavelength) and the UV range (280 nm to 400 nm). In a further development of the invention, the emitted radiation of one light source only includes a partial wavelength range between 280 nm and 500 nm. In a preferred embodiment, the wavelength range of the radiation emitted by one light source is less than 50 nm, and in a particularly preferred embodiment, one light source is a single LED.

[0043] In a further development of the invention, individual light sources can be controlled. This enables targeted control of the light sources and targeted adjustment of the overall spectrum to suit different applications. By appropriately selecting the intensity of the light source, a radiation dose can also be achieved, which can be in the form of a single dose (e.g., 0.1 MED) or in the form of an adjustable limit value. This minimizes the radiation dose to the test subject.

[0044] In yet another aspect of the invention, the light source is controlled by a light source controller. The light source control specifically controls the light source and is capable of targeted adjustment of the spectrum generated by the light source, for example, by controlling the wavelength range and intensity of the electromagnetic radiation generated by the light source.

[0045] In yet another embodiment of the invention, the wavelength, exposure time, and / or intensity of individual light sources are controlled by controlling the light source. On the one hand, this enables targeted control of the light source for in-vivo measurements and in-vitro measurements. By appropriately selecting the intensity of the light source and the exposure time of the measurement subject, a radiation dose can also be selected, which can be in the form of an individual dose (e.g., 0.1 MED) or in the form of an adjustable limit value. This minimizes the radiation dose to the test subject.

[0046] In yet another aspect of the invention, the detected diffusely reflected radiation is used to adjust the transmission spectrum. The adjustment is carried out in such a way that the mixed transmission spectrum T hyb is determined according to the following equation:

[0047]

[0048] where T in vivo is the transmission spectrum determined as a function of the spectrum of the detected diffusely reflected radiation determined by in-vivo measurements, and T insilico As the calculated transmission spectrum.

[0049] In a further embodiment of the invention, according to ISO 24442, the radiation is emitted in vivo on human skin. ISO 24442 defines an in vivo method in which the minimum UVA dose required to produce irreversible skin pigmentation (tanning) is used to determine the UVA protection factor.

[0050] In a further advantageous embodiment of the invention, the protective ability of the protective means is evaluated based on two measurements. The protective ability of the protective means is measured by the time it takes for UVB rays to penetrate the protective means and cause skin reddening (minimal erythema, MED). In the second measurement, the dose of solar radiation required to cause skin reddening in the first measurement is divided by the dose required to cause skin reddening in the absence of the protective means, compared to the time taken in the absence of the protective means.

[0051] In a further development of the invention, the first measurement is carried out before applying the protective means to the measurement subject. This first measurement records the time at which minimal erythema (MED) appears on the untreated skin of the test subject.

[0052] In a further aspect of the invention, the second measurement is carried out after applying the protective means to the measurement subject. The second measurement records the time at which minimal erythema (MED) appears on the skin of the test subject treated with the protective means.

[0053] In a further embodiment of the invention, the light beam source generates polychromatic radiation, and the generated polychromatic radiation is radiated onto the measurement subject without being filtered. The light beam source generates radiation in the maximum wavelength range from 280 nm to 500 nm (UVB to blue light). From the generation of the polychromatic radiation until it hits the measurement subject, the generated polychromatic radiation is not altered by optical elements (filters, monochromators) within the generated wavelength range. This results in the generated radiation having the maximum intensity, and similarly the diffusely reflected or transmitted radiation also has the maximum intensity, and thus has a high signal-to-noise ratio.

[0054] In a further development of the invention, the measurement of the remission spectrum and / or remission value is carried out only in vivo. In the first measurement, the remission spectrum and / or remission value of the human skin without the protective means is recorded, and in the second measurement, the remission spectrum and / or remission value of the human skin without the protective means is recorded.

[0055] The object is further achieved by an SPF evaluation system for evaluating the protection factor of a protective means according to claim 25. Further advantageous embodiments of the invention are also set forth in the dependent claims.

[0056] The SPF evaluation system for evaluating the protection factor of a protection means according to the present invention includes a measuring device, wherein the measuring device includes a light beam source device. The light beam source device includes a light beam source, a detector unit, a control unit for controlling the measuring device, and an evaluation unit.

[0057] The measuring device is adapted to introduce electromagnetic radiation into a measurement subject, preferably human skin, by means of the light beam source. The light beam source is a technical device for generating electromagnetic radiation.

[0058] In addition, the measuring device is adapted to detect diffusely reflected electromagnetic radiation. The measuring device can be controlled by means of the control unit, and the radiation detected by the detector unit can also be processed by means of the control unit. The detection window and resolution of the spectrometer are determined by the control unit, and the detected signal is stored, processed (e.g., amplified), displayed, and evaluated by the evaluation unit.

[0059] In a further development of the present invention, the SPF evaluation system is adapted to evaluate the protection ability of a protection means to protect against light in an evaluation wavelength range. The evaluation wavelength range is the wavelength range for measuring the protection factor. The evaluation wavelength range is different from the wavelength range of the radiation wavelength and / or the detection wavelength, wherein the wavelength range of the evaluation wavelength range at least includes the wavelength ranges of the radiation wavelength and the detection wavelength.

[0060] In an advantageous embodiment of the present invention, the SPF evaluation system has exactly one measuring device. In a further development of the present invention, exactly one measuring device has exactly one light beam source device. In a further aspect of the present invention, exactly one light beam source device includes exactly one light beam source. According to the present invention, the measurement and detection of electromagnetic radiation are not carried out using the sum spectra generated by different light beam sources, but only using exactly one measuring device, exactly one light beam source device, and exactly one light beam source, wherein the light beam source is preferably an LED. This makes the SPF evaluation system according to the present invention more compact and more cost-effective than known systems.

[0061] In a further embodiment of the present invention, exactly one light beam source device can be controlled by exactly one control unit for controlling the measuring device. The control unit can control the wavelength range and intensity of the radiation emitted by the light beam source device.

[0062] In yet another embodiment of the present invention, exactly one measuring device has exactly one detector unit. In yet another development of the present invention, exactly one detector unit has exactly one detector. In yet another embodiment of the present invention, exactly one detector can be controlled by exactly one control unit for controlling the measuring device. The detector unit includes, for example, a monochromator, a filter, a photomultiplier tube, a spectrometer and / or a photodiode. All of these known devices are suitable for detecting electromagnetic radiation and measuring its intensity depending on the wavelength. Preferably, a photodiode is used to perform the detection of in-vivo measurements. This makes the SPF evaluation system according to the present invention more compact and more cost-effective than known systems. The detection window and resolution of the spectrometer are set by the control unit, and the detected signal is stored, processed (e.g., amplified) and displayed by the control unit.

[0063] In yet another embodiment of the present invention, exactly one beam source device is suitable for emitting light at a radiation wavelength, wherein the wavelength range of the radiation wavelength is less than the wavelength range of the evaluation wavelength. Exactly one beam source device generates electromagnetic radiation at a radiation wavelength between the blue spectral range (from approximately 400 nm to 500 nm wavelength) and the UV range (280 nm to 400 nm). The evaluation wavelength is the wavelength at which the protection factor is determined. The evaluation wavelength is different from the wavelength range of the radiation wavelength. The evaluation wavelength is similar to the radiation wavelength and preferably is a wavelength range, wherein the wavelength range of the evaluation wavelength at least includes the wavelength range of the radiation wavelength.

[0064] In yet another embodiment of the present invention, exactly one detector unit is suitable for detecting light at a detection wavelength, wherein the wavelength range of the detection wavelength is less than the wavelength range of the evaluation wavelength. Similar to the radiation wavelength, the detection wavelength preferably includes a wavelength range, wherein the wavelength range of the detection wavelength preferably lies within or includes the range of the radiation wavelength.

[0065] In yet another embodiment of the present invention, the wavelength range of the radiation wavelength or the detection wavelength within the wavelength range of the evaluation wavelength is less than the wavelength range of the evaluation wavelength. For recording in-vivo measurements, the wavelength range of the radiation wavelength particularly includes the UVA wavelength range (320 nm to 400 nm) irradiated into the measurement subject. The wavelength range of the detection wavelength covers the maximum value of the wavelength range of the radiation wavelength (320 nm to 400 nm). The wavelength range of the evaluation wavelength covers a wider range, particularly for evaluating the wavelength range from 280 nm to 500 nm (UVB to blue light).

[0066] In a further development of the invention, the wavelength range of the radiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm. Thus, only one steel source is required to emit electromagnetic radiation with a very narrow wavelength range of the radiation wavelength. Similarly, for recording the reflection spectrum, a detector capable of detecting a small wavelength range of the detection wavelength is required. Thus, a light beam source and a detector can be realized such that they can be manufactured and operated cost-effectively.

[0067] In a further embodiment of the invention, the SPF evaluation system has exactly one control unit. The control unit is typically a PC or a laptop with a suitable computer program. With the aid of the control unit, the SPF evaluation system can be controlled; in addition, the control unit can also process the radiation detected by the detector unit. By means of the control device, the wavelength range of the detection wavelength and the resolution of the detector unit are determined, and the detected signal is stored, processed (e.g., amplified) and displayed. This enables targeted control of the light beam source and targeted adjustment of the overall spectrum to suit different applications. By appropriately selecting the intensity of the light beam source, a radiation dose can also be achieved, which can be in the form of a single dose (e.g., 0.1 MED) or in the form of an adjustable limit value. This minimizes the radiation dose to the test object.

[0068] In an advantageous embodiment of the invention, the SPF evaluation system is suitable for evaluating the protective ability of a protective means against light and / or for evaluating the protection factor of a protective means using only the measurement data from a measurement data device. The evaluation is carried out by means of the inventive method for determining the protection factor according to claims 1 to 24. With the aid of the SPF evaluation system, the diffusely reflected radiation of an irradiated measurement subject (human skin without and with a protective means) can be detected. The evaluation of the protective means is carried out using data from the remission spectrum and taking into account data from the transmission spectrum, wherein according to the invention, the data from the transmission spectrum are electronic data.

[0069] Exemplary embodiments of the method according to the invention for determining the protection factor including spectral measurement and the SPF evaluation system according to the invention for evaluating the protection factor of a protective means are schematically shown in a simplified form in the figures and are explained in more detail in the following description.

[0070] In the figures:

[0071] Figure 1 : SPF evaluation system, with the evaluation unit arranged outside the measurement device

[0072] Figure 2 : SPF evaluation system, with the control unit and the evaluation unit arranged in one device

[0073] Figure 3: SPF evaluation system, the beam source control unit is controlled by the control unit

[0074] Figure 4 : SPF evaluation system, the control unit and the evaluation unit are arranged separately in one device

[0075] Figure 5 : SPF evaluation system, the control unit, the beam source control unit and the evaluation unit are arranged in one device

[0076] Figure 6 : Method for performing spectral measurement (in vivo) to record the reflection spectrum

[0077] Figure 7 : Combined method for determining the protection factor by using the measurement to record the reflection spectrum and the electronic data in the form of the transmission spectrum

[0078] Figure 1 Schematically shows an embodiment of the SPF evaluation system 1 for performing in vivo measurement according to the present invention. The SPF evaluation system 1 includes a measurement device 6 having a beam source device 12. The beam source device 12 includes a beam source 12.1 and optical elements designed and / or suitable for adjusting and / or redirecting the radiation generated by the beam source 12.1, such as optical fibers, filters, monochromators, mirrors and / or other optical elements.

[0079] By means of the optical fiber 4.1, the light at the radiation wavelength between 280 nm and 500 nm emitted by the beam source device 12 is introduced into the measurement subject 3 through the probe 5. The light reflected by the measurement subject 3 reaches the detector unit 13 through another optical fiber 4.2. The detector unit 13 has a monochromator, a filter, a photomultiplier tube, a spectrometer and / or a photodiode. In this embodiment and all subsequent embodiments, the detector unit 13 includes a photodiode. The detector unit 13 and the beam source device 12 are connected to the control unit 2 via data lines 23, 24, and the control unit is in turn connected to the evaluation unit 10 via another data line 25. The control unit 2 is usually a PC or a laptop with a suitable computer program. The control unit 2 and the detector unit 13 are also connected to each other via the data line 22.

[0080] Figure 2 Shows another embodiment of the SPF evaluation system 1 according to the present invention. The SPF evaluation system 1 also has a measurement device 6 with a beam source device 12. By means of the optical fiber 4.1, the light emitted by the beam source device 12 is introduced into the measurement subject 3 through the probe 5, and the light reflected by the measurement subject 3 reaches the detector unit 13 through another optical fiber 4.2. The detector unit 13 and the beam source device 12 are connected to the control unit 2 via data lines 23, 24, and the control unit forms a structural unit together with the evaluation unit 10 in this embodiment.

[0081] Figure 3 Shows yet another embodiment of the SPF evaluation system 1 also for performing in-vivo measurements according to the present invention. The SPF evaluation system 1 has a measuring device 6 with a light beam source device 12. By means of an optical waveguide 4.1, the light emitted by the light beam source device 12 is introduced into the measurement subject 3 via a probe 5, and the light reflected by the measurement subject 3 reaches a detector unit 13 via another optical waveguide 4.2. The detector unit 13 and the light beam source device 12 are connected to a light beam source control 11 via data lines 23, 24. The light beam source control 11 and the detector unit 13 are each connected to a control unit 2 via a data line 21. The evaluation unit 10 is arranged separately and is also connected to the control unit 2 and the light beam source control 11 via a data line 21.

[0082] Figure 4 Shows yet another embodiment of the SPF evaluation system 1 according to the present invention. The SPF evaluation system 1 also has a light beam source device 12. By means of an optical waveguide 4.1, the light emitted by the light beam source device 12 is introduced into the measurement subject 3 via a probe 5, and the light reflected by the measurement subject 3 reaches a detector unit 13 via another optical waveguide 4.2. The detector unit 13 and the light beam source device 12 are connected to a light beam source control 11 via data lines 23, 24. In this embodiment, the control unit 2 is arranged together with the evaluation unit in a structural unit remote from the SPF evaluation system 1 and is connected to the structural unit via an interface 16. The connection can be wired or wireless, for example via an IP connection, Bluetooth, etc. On the one hand, the interface 16 is connected to the detector unit 13 to each other, and on the other hand, the interface 16 and the light beam source control 11 are connected to each other via data lines 21, 22.

[0083] Figure 5 Shows a preferred embodiment of the SPF evaluation system 1 also for performing in-vivo measurements according to the present invention. The SPF evaluation system 1 corresponds to the system presented in the first embodiment (see Figure 1 )), that is, the SPF evaluation system 1, only the control unit 2 is arranged together with the light beam source control 11 and the evaluation unit 10 in the structural unit of the measuring device 6. The SPF evaluation system 1 has exactly one measuring device 6, and the exactly one measuring device has exactly one light beam source 12.1 and exactly one detector unit 13. The light beam source 12.1 is an LED, and the detector unit 13 is a photodiode. Exactly one control unit 2 having exactly one evaluation unit 10 and exactly one light beam source control 11 in the structural unit controls exactly one light beam source 12.1 via a data line 23 and receives data from exactly one detector unit 13 via a data line 24. The SPF evaluation system 1 presented here has a particularly compact design, requires only a small number of components, and is therefore cost-effective to manufacture and use.

[0084] Figure 6 An embodiment showing an implementation of the in-vivo measurement method 100, the in-vivo measurement being used to detect the remission spectrum by means of the SPF evaluation system 1 according to the invention from a previous embodiment (see Figures 1 to 5 ). The test is carried out in-vivo according to ISO24442 or 24444. The measurement method 100 requires recording the remission spectrum of the skin of the test subject 3 without treatment by protective means and the remission spectrum of the treated skin by protective means.

[0085] For this purpose, the probe 5 is applied to the untreated skin of the test subject 3, i.e., the protective means to be tested is not applied to the skin of the test subject 3. For this purpose, a location on the inner forearm or back of the test subject 3 is usually selected. Then, the first measurement 110 is carried out by controlling the LED 12.1 through the light source control 11, so that the light emitted by the LED 12.1 (see Figure 4 ) is guided to the skin of the test subject 3 through the light guide 4.1.

[0086] The generated electromagnetic radiation has a radiation wavelength range with an FWHM of up to 20 nm, wherein the generated electromagnetic radiation is in the wavelength range from 330 nm to 350 nm. The wavelength range of the detection wavelength of the diffusely reflected radiation detected by the detector unit 13 through the light guide 4.2 also has a range of 20 nm, for example, in the range from 330 nm to 350 nm. Moreover, the range of the radiation wavelength and / or the range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm.

[0087] For some applications, the FWHM can be up to 30 nm, wherein the generated electromagnetic radiation is in the wavelength range from 400 nm to 800 nm. For other applications, an FWHM of up to 100 nm or higher can be used, and / or the FWHM can be reduced by a filter as needed, wherein the generated electromagnetic radiation is in the wavelength range from 800 nm to 2000 nm.

[0088] The light generated by the LED 12.1 irradiates the measurement subject 3 without filtering to ensure a high S / N ratio. Specifically, the light generated by the LED 12.1 is polychromatic, with the maximum intensity at a wavelength in the UVA range of 340 nm. Alternatively, an LED that generates light with the maximum intensity in the UVA range of 365 nm can also be used. The radiation intensity does not cause acute damage to the skin, which is lower than the simple MED, or lower than the MPE [maximum permissible exposure] value, or significantly lower than the value caused by solar radiation. The light diffusely reflected by the skin of the test subject 3 is guided through the light guide 4.2 to the photodiode of the detector unit 13, detected by the photodiode and converted into a measured value, and the measured value is sent to the control unit 2 and stored in the control unit 2.

[0089] Then, the control unit 2 queries 120 whether a second measurement has been performed on the skin of the test subject 3 that has been treated with the protection means. If this is not the case, the control unit 2 will indicate this. In order to perform the second measurement 110 in the presence of the protection means, the protection means is applied 130 to the skin of the test subject 3, for example, in an amount of 2.0 mg / cm on the skin surface to be tested, in accordance with ISO 24442 or 24444. 2 The application 130 of the protection means and the subsequent second measurement 110 are performed at the same location of the measurement sample 3, in particular at the same location on the skin of the test subject, to ensure the reproducibility of the first and second measurements 110. Also to ensure reproducibility, the control unit 2 controls the light source control 11 in such a way that the light source control 11 controls the LED 12.1 such that the light generated by the LED 12.1 is guided through the light guide 4.1 onto the skin of the test subject 3, where the intensities and / or exposure times of the first and second measurements 110 are coordinated with each other.

[0090] The light diffusely reflected by the skin of the test subject 3 is also detected by the photodiodes of the detector unit 13 and converted into a measured value. The measured value is sent to the control unit 2 and stored in the control unit 2.

[0091] If the query 120 shows that the second measurement 110 has been performed, an evaluation 140 of the protection means is performed. For this purpose, the control unit 2 executes a program to calculate the reflection spectrum T according to Equation 1 in vivo :

[0092]

[0093] Equation 1

[0094] where T in vivo is a function of the wavelength λ, SPF in vivo is the protection factor determined by the in-vivo method 100, R0 is the reflected intensity of the untreated skin of the test subject 3 as a function of the wavelength λ, and R is the reflected intensity of the skin of the test subject 3 treated with the protection means as a function of the wavelength λ. The method 100 presented here takes from a few seconds to several tens of seconds.

[0095] As Figure 6 an alternative to the method using one LED as shown, this method can also be performed in the same way using a multi-LED radiation source.

[0096] Figure 7 shows a combined in-vivo reflectance measurement 100 for performing data including the transmission spectrum 200 according to the present invention (seeFigure 5 ) The method 400 of the implementation. According to the present invention, the value of the transmission spectrum 200 is calculated (electronically).

[0097] If the amount and nature of the UV filter substance of the protection means are known, the UV transmittance can be calculated, taking into account the irregularity of the film and its photodegradability. Based on the simulated UV transmittance, the SPF and all parameters characterizing the protection against UVA and / or UVB can be calculated electronically.

[0098] The data of the transmission spectrum 200 are determined electronically according to ISO 24443. It is assumed that 2.0 g / cm 2 of the protection means is applied. It is assumed that the emitted radiation is in the wavelength range from 280 nm to 500 nm (UVB to blue light), so the wavelength range includes the maximum wavelength range from 280 nm to 500 nm of the evaluation wavelength.

[0099] The results of the evaluation of the in vivo remission spectrum 140 and the electronic transmission spectrum 200 are evaluated together 300. For this purpose, first the mixed transmission spectrum T hyb is calculated, where the electronic transmission spectrum T in silico is scaled by the reflection spectrum T in vivo as follows:

[0100] The two results of the individual evaluations 140, 230 are combined and evaluated 300. For this purpose, the mixed transmission spectrum T hyb is calculated, where the in vitro transmission spectrum T in silico is scaled by the reflection spectrum T in vivo as follows:

[0101]

[0102] Then, according to Equation 4, the protection ability of the protection means against SF in the spectral range from UVA (320 nm) to the HEV spectral range (450 nm) is calculated (where E = IPD(λ) is the IPD spectrum; S = I(λ) is the solar spectrum):

[0103]

[0104] According to Equation 5, the protection ability of the protection means in the blue light spectral range (400 nm to 500 nm) of interest of the present invention is determined (where E = IPD(λ) is the IPD spectrum; S = I(λ) is the solar spectrum):

[0105]

[0106] Determine the protection ability of the protection means against SF (from 400 nm to 450 nm) from 400 nm to 450 nm according to Equation 6 (where E = IPD(λ) is the IPD spectrum; S = I(λ) is the solar spectrum):

[0107]

[0108] Then, calculate the protection ability of the protection means against the UVA (from 320 nm to 400 nm) UVA-SF spectral range according to Equation 4 (where E = PPD(λ) is the PPD spectrum; S = I(λ) is the solar spectrum for PPD-test or the UVA source):

[0109]

[0110] The protection ability of the protection means against the UVB to UVA (from 280 nm to 400 nm) UV-SF spectral range is given by Equation 4:

[0111]

[0112] In all SF or UVA-SR equations, use an optional correction function F(SF)=SF_korr or F(UVA-SF)=UVA-PF_korr that describes, for example, the skin type-dependent difference. The correction function makes the values for different skin types comparable and outputs the corrected value SF korr or UVA-PF korr .

[0113] For example, F can be a linear factor (i.e., F(SF)=SF×C) or an exponential function (i.e., F(SF)=SF C ). For example, C can depend on the skin type or the ITA° value. As shown in Equation 4, the formulas in Equations 2 to 8 can be written in the following form:

[0114]

[0115] Since the in vivo values are measured without photodegradation, photodegradation should be appropriately considered. This can be achieved by calculating T_in silico in the case of T in silico_irr (λ) and without photodegradation, and calculating the spectral quotient from it:

[0116]

[0117] In this case,

[0118] T hyb_irr (=T hyb (λ)*SRPD(λ)

[0119] Equation 11

[0120] Then it is calculated.

[0121] The method can be calibrated using a suitable reference method (such as electron spin resonance spectroscopy).

[0122] List of reference numerals

[0123] 1 SPF evaluation system

[0124] 2 Control device

[0125] 3 Sample / measurement subject

[0126] 4.1, 4.2 Light guide / fiber optic bundle

[0127] 5 Probe

[0128] 6 Measuring device

[0129] 10 Evaluation device

[0130] 11 Beam source control

[0131] 12 Beam source device

[0132] 12.1 Beam source

[0133] 13 Detection unit

[0134] 21 Connection beam source control - control device

[0135] 22 Connection detector / spectrometer - control device

[0136] 23 Connection beam source control - beam source device

[0137] 24 Connection beam source control - detection unit

[0138] 25 Connection control device - evaluation device

[0139] 100 Method for recording spectral measurements (in vivo)

[0140] 110 Perform reflection spectral measurement

[0141] 120 Query

[0142] 130 Apply protective means

[0143] 140 Evaluation of reflection spectrum

[0144] 200 Method for determining data of transmission spectrum

[0145] 300 Determine protection factor

[0146] 400 Method for determining a protection factor

Claims

1. A method (400) for determining a protection factor, comprising the following steps: · Emitting radiation from a light beam source (12.1), wherein the emitted radiation includes light at a radiation wavelength between 280 nm and 2000 nm, preferably between 280 nm and 800 nm, and particularly preferably between 280 nm and 500 nm. · Irradiating a measurement subject (3) with the emitted radiation. · Detecting the radiation diffusely reflected by the irradiated measurement subject (3) at a detection wavelength. · Evaluating the protection factor of a protection means based on the diffusely reflected radiation and a transmission spectrum using an evaluation wavelength. Wherein data of the transmission spectrum is used to evaluate the protection factor of the protection means. Wherein the evaluation wavelength is different from the wavelength range of the radiation wavelength and / or the detection wavelength, and wherein the transmission spectrum data is electronic data.

2. The method (400) for determining a protection factor according to claim 1. Characterized in that The wavelength range of the transmission spectrum includes the evaluation wavelength.

3. The method (400) for determining a protection factor according to claim 1 or 2. Characterized in that The evaluation wavelength covers a wavelength range from 280 nm to 2000 nm, preferably from 280 nm to 800 nm, or particularly preferably from 280 nm to 500 nm, and / or from 400 nm to 500 nm, and / or from 400 nm to 450 nm.

4. The method (400) for determining a protection factor according to claim 3. Characterized in that The evaluation of the protection ability of the protection means for light in the wavelength range from 400 nm to 500 nm is carried out in a process separate from the evaluation of the protection ability of the protection means for light in the wavelength range from 280 nm to 400 nm.

5. The method (400) for determining a protection factor according to claim 4. Characterized in that The evaluation of the protection ability of the protection means for light in the wavelength range from 400 nm to 500 nm is carried out in a process separate from the evaluation of the protection ability of the protection means for light in the wavelength range from 280 nm to 400 nm.

6. The method (400) for determining a protection factor according to one or more of the preceding claims. Characterized in that The wavelength range of the radiation wavelength or the wavelength range of the detection wavelength is smaller than the wavelength range of the evaluation wavelength.

7. The method (400) for determining a protection factor according to claim 6. Characterized in that The wavelength range of the radiation wavelength or the wavelength range of the detection wavelength within the wavelength range of the evaluation wavelength is smaller than the wavelength range of the evaluation wavelength.

8. The method (400) for determining a protection factor according to one or more of the preceding claims. Characterized in that The range of the radiation wavelength and / or the wavelength range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm.

9. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the radiation wavelength and / or the detection wavelength only includes light outside the wavelength range of 400 nm to 450 nm.

10. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the radiation wavelength and / or the detection wavelength only includes light outside the wavelength range of 400 nm to 500 nm.

11. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the evaluation wavelength includes wavelengths outside the wavelength range of 400 nm to 500 nm.

12. The method (400) for determining a protection factor according to claim 11, characterized in that the evaluation wavelength includes a wavelength λ, where λ < 400 nm.

13. The method (400) for determining a protection factor according to claim 12, characterized in that the evaluation wavelength includes a wavelength λ, where 320 nm < λ < 400 nm.

14. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the emission of the radiation is generated by a single light beam source (12.1), and the radiation wavelength of the light beam source (12.1) includes light in the wavelength range between 280 nm and 500 nm.

15. The method (400) for determining a protection factor according to claim 14, characterized in that the individual light beam source (12.1) can be controlled.

16. The method (400) for determining a protection factor according to claim 14 or 15, characterized in that the control of the light beam source (12.1) is controlled by a light beam source control member (11).

17. The method (400) for determining a protection factor according to claim 16, characterized in that by controlling the light beam source (12.1), the wavelength, exposure time and / or intensity of the individual light beam source (12.1) are controlled.

18. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the detected diffusely reflected radiation is used to adjust the transmission spectrum.

19. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the radiation is emitted into the human skin in vivo.

20. The method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the evaluation of the protection ability of the protection means is carried out based on two measurements.

21. The method (400) for determining a protection factor according to claim 20, characterized in that a first measurement is carried out before applying the protection means to the measurement subject (3).

22. The method (400) for determining a protection factor according to claim 20 or 21, characterized in that A second measurement is carried out after applying the protection means (130) to the measurement subject (3).

23. A method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the light beam source (12.1) generates polychromatic radiation, and the generated polychromatic radiation irradiates the measurement subject (3) without being filtered.

24. A method (400) for determining a protection factor according to one or more of the preceding claims, characterized in that the spectral measurement (100) is carried out only in vivo.

25. An SPF evaluation system (1) for evaluating the protection factor of a protection product, the SPF evaluation system comprising the following components: · A measurement device (6), the measurement device having - A light beam source device (12), wherein the light beam source device (12) includes a light beam source (12.1), - A detector unit (13); · A control unit (2) for controlling the measurement device (6); · An evaluation unit (10).

26. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 25, characterized in that the SPF evaluation system (1) is adapted to evaluate the protection ability of the protection means to protect against light in the evaluation wavelength range.

27. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 25 or 26, characterized in that the SPF evaluation system (1) has exactly one measurement device (6).

28. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 27, characterized in that the exactly one measurement device (6) has exactly one light beam source device (12).

29. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 28, characterized in that the exactly one light beam source device (12) has exactly one light beam source (12.1).

30. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 28 or 29, characterized in that the exactly one light beam source device (12) can be controlled by exactly one control unit (2) for controlling the measurement device (6).

31. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to one or more of claims 27 to 30, characterized in that the exactly one measurement device (6) has exactly one detection unit (13).

32. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 31, characterized in that the exactly one detection unit (13) has exactly one detector.

33. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 31 or 32, characterized in that the exactly one detection unit (13) can be controlled by exactly one control unit (2) for controlling the measurement device (6).

34. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to one or more of claims 26 to 33, characterized in that the exactly one light source device (12) is adapted to emit light at a radiation wavelength, wherein the wavelength range of the radiation wavelength is less than the wavelength range of the evaluation wavelength.

35. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to one or more of claims 26 to 34, characterized in that the exactly one detection unit (13) is adapted to detect light at a detection wavelength, wherein the wavelength range of the radiation wavelength is less than the wavelength range of the evaluation wavelength.

36. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to claim 34 or 35, characterized in that the wavelength range of the radiation wavelength or the wavelength range of the detection wavelength in the wavelength range of the evaluation wavelength is less than the wavelength range of the evaluation wavelength.

37. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to one or more of claims 34 to 36, characterized in that the range of the radiation wavelength and / or the range of the detection wavelength is less than 100 nm, preferably less than 50 nm, and particularly preferably less than 25 nm.

38. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to one or more of claims 25 to 37, characterized in that the SPF evaluation system (1) has exactly one control unit (2).

39. The SPF evaluation system (1) for evaluating the protection factor of a protection means according to one or more of claims 25 to 38, characterized in that the SPF evaluation system (1) is adapted to evaluate the protection ability of the protection means against light and / or the protection factor of the protection means only using the measurement data from the measurement data device (6).

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