In-vitro evaluation method of make-up removal products for cleansing ability of make-up

Abstract

The application discloses a kind of in-vitro evaluation methods of the cleaning ability of makeup product to base makeup, comprising the following steps: (1) providing detection instrument: SPF290S sunscreen index measuring instrument;(2) providing substrate: PMMA plate;(3) the light transmittance T0 of substrate is determined;(4) preparing base makeup test plate: base makeup product is evenly applied to substrate;(5) the light transmittance T1 of base makeup test plate is determined;(6) washing base makeup test plate: base makeup test plate is washed with makeup remover;(7) the light transmittance T2 of base makeup test plate after washing is determined;(8) calculate cleaning power: in formula: X---the cleaning power of makeup remover, %;T0---the light transmittance of substrate;T1---the light transmittance of base makeup test plate;T2---the light transmittance of base makeup test plate after washing.

Description

Technical Field

[0001] This invention relates to the field of cosmetic testing, and more specifically to an in vitro evaluation method for the ability of makeup remover products to remove base makeup. Background Technology

[0002] Makeup, as an important part of cosmetics, comes in a wide variety of products, with base makeup products, which correct skin tone and cover blemishes, being the most widely used for daily wear. Base makeup products contain pigments and other ingredients that require dedicated makeup removers for cleansing. Inadequate cleansing can lead to long-term residue buildup and damage to the skin. Therefore, evaluating the cleansing ability of makeup removers on base makeup is a crucial issue in product development. Common evaluation methods include human trials, where evaluators or consumers conduct self-assessments after trying the product, which involves a degree of subjectivity. Other human methods include using image acquisition instruments combined with image analysis systems or colorimeters, but these methods inevitably suffer from significant individual differences and high testing costs. In vitro methods have been reported to involve applying samples to leather and then evaluating them with a colorimeter, but the consistency of roughness between batches of leather can affect the comparability of data.

[0003] This invention is the first to use an SPF290S sun protection factor analyzer to in vitro test the ability of makeup removers to remove base makeup. The SPF290S is a widely used specialized device in the cosmetics industry for in vitro determination of sun protection factor (SPF). A search revealed no other applications of the SPF in addition to SPF measurement. Using foundation as a typical sample and polymethyl methacrylate (PMMA) plates as a carrier, this invention is the first to use an SPF analyzer to in vitro evaluate the ability of makeup removers to remove base makeup. The sample-coated substrate is irradiated with 290nm-400nm ultraviolet light generated by a xenon lamp. Part of the incident light is reflected or absorbed, while the portion that passes through the substrate is collected by a spherical integrator, which can measure the transmittance of non-transparent samples. The PMMA plate, as a carrier, has a surface roughness of 5μm, which effectively simulates the roughness of the skin surface, and as a commercially available product, it ensures good stability of the 5μm roughness.

[0004] Therefore, this invention provides an in vitro evaluation method for the makeup removal ability of makeup removers, which evaluates the cleansing ability of makeup removers by the change in light transmittance before and after washing, and has the advantages of simple operation and low cost. Summary of the Invention

[0005] This invention discloses an in vitro evaluation method for the makeup removal product's ability to remove base makeup, which evaluates the product's cleaning ability by the change in light transmittance before and after washing.

[0006] On one hand, the present invention provides an in vitro evaluation method for the makeup removal ability of makeup remover products, comprising the following steps:

[0007] (1) Provide testing equipment: SPF290S sun protection index meter;

[0008] (2) Provide substrate: PMMA board (5cm*5cm, 5μm roughness);

[0009] (3) Measure the transmittance T0 of the substrate;

[0010] (4) Preparation of the base makeup test plate: Apply the base makeup product evenly to the substrate, with an application amount of 2 mg / cm². 2 ;

[0011] (5) Measure the light transmittance T1 of the base makeup test plate;

[0012] (6) Cleaning the makeup test strip: Clean the makeup test strip with makeup remover, following the product instructions. The product dosage is 20mg / cm³. 2 ;

[0013] (7) Measure the light transmittance T2 of the base makeup test plate after cleaning;

[0014] (8) Calculate cleaning power:

[0015]

[0016] In the formula:

[0017] X – Cleansing power of the makeup remover, %;

[0018] T0—Light transmittance of the substrate;

[0019] T1 – Light transmittance of the foundation test panel;

[0020] T2 – Light transmittance of the test plate after cleaning the base makeup.

[0021] In a preferred embodiment, after the application of the base makeup in step (4), the base makeup test plate is placed at room temperature to form a film, and more preferably, the film formation time is 30 minutes.

[0022] In a preferred embodiment, after cleaning in step (6), the back of the board is gently wiped with a paper towel to remove moisture, and the base makeup test board is placed at room temperature to dry, more preferably for 30 minutes.

[0023] In a preferred embodiment, the SPF290S instrument scans in the wavelength range of 290nm-400nm with a scanning interval of 2nm. The transmittance at a single wavelength is taken as the average of 9 points, and the cleaning power is calculated using the transmittance across the entire wavelength range, which is calculated by summing the transmittance at each single wavelength range and dividing by 56.

[0024] In a preferred embodiment, the base makeup product is a liquid foundation.

[0025] In a preferred embodiment, the makeup remover is selected from: makeup remover oil, makeup remover balm, makeup remover water, or makeup remover wipes. Detailed Implementation

[0026] This invention relates to the field of detection methods in cosmetics, specifically to the use of an SPF-290S sun protection index meter to evaluate the ability of makeup remover products to remove base makeup in vitro. The method described in this invention is simple, fast, and low-cost.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. While any methods and materials similar to or equivalent to those described herein may be used to practice or test the invention, preferred methods and materials are described herein.

[0028] The apparatus, device, method, component, and / or composition of the present invention may include the components of the present invention and other ingredients described herein, consist substantially of the components of the present invention and other ingredients described herein, or consist of the components of the present invention and other ingredients described herein. As used herein, "consistently of" means that the apparatus, device, method, component, and / or composition may contain additional components, provided that the additional components do not substantially alter the essential and novel features of the apparatus, device, method, component, and / or composition protected by the claims.

[0029] Unless otherwise specified, all percentages and ratios used herein are by weight of the total composition, and all measurements were performed at 25°C.

[0030] Unless otherwise specified, all measurements used in this article are in metric units.

[0031] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.

[0032] 1. Materials

[0033] Foundation: Foundation A (a best-selling product on the market, purchased from the brand's official flagship store on Tmall).

[0034] Makeup removal products: Cleansing oil #1, Cleansing oil #2, Cleansing oil #3, Cleansing oil #4, Cleansing balm #5, Cleansing balm #6, Cleansing balm #7, Makeup removal wipes #8 (all best-selling products, purchased from the brand's official flagship store on Tmall). Specific information is as follows:

[0035]

[0036]

[0037] 2. Instruments and equipment

[0038] SPF290S Sun Protection Factor Tester (Optometrics Corporation);

[0039] CR-300 colorimeter (MINOLTA);

[0040] PMMA board (5cm*5cm, 5μm, Beijing Jinhongfan);

[0041] Ceramic standard whiteboard (National Building Materials Bureau Standardization Research Institute).

[0042] 3. Determination of T0

[0043] A PMMA plate (substrate) without any sample coating was used as a blank sample and placed on an SPF290S measuring holder to measure its transmittance. This transmittance was recorded as T0 and used as the transmittance of the substrate.

[0044] 4. Preparation of the base makeup test plate

[0045] Choose liquid foundation as a typical example of base makeup products, and use 2mg / cm³. 2 To determine the amount to apply, use your index finger to evenly spread the foundation onto the substrate in a circular motion. Before applying the sample to the substrate, smear the sample onto your finger first, then wipe away any excess sample with a tissue to ensure the sample is saturated on your finger. This prevents your finger from carrying away sample during the actual application, which could affect the amount of sample applied. After completing the sample application, place the foundation test panel at room temperature for 30 minutes to allow the film to form.

[0046] 5. Determination of T1

[0047] The transmittance of the base makeup test plate was measured on the SPF290S test holder and recorded as the transmittance of the base makeup test plate, denoted as T1.

[0048] 6. Cleaning the foundation test plate

[0049] The test sample was cleaned with makeup remover at a concentration of 20 mg / cm³. 2 Cleaning method follows the product instructions. After cleaning, gently wipe the back of the test panel with a paper towel to remove moisture, and place the test panel at room temperature to dry for 30 minutes.

[0050] 7. Determination of T2

[0051] The cleaned base makeup test plate was placed on the SPF290S measuring holder to measure its transmittance, which was taken as the transmittance of the cleaned base makeup test plate and denoted as T2.

[0052] 8. Calculation of cleaning power:

[0053]

[0054] In the formula:

[0055] X – Cleansing power of the makeup remover, %;

[0056] T0—Light transmittance of the substrate;

[0057] T1 – Light transmittance of the foundation test panel;

[0058] T2 – Light transmittance of the test plate after cleaning the base makeup.

[0059] 9. Use SPF-290S to measure light transmittance.

[0060] Before measuring the transmittance of the sample, a reference scan is performed: the PMMA plate without any sample coating is placed on the measurement holder, and the center position point is selected for the reference scan.

[0061] Sample scanning: The treated PMMA plate was placed on the measuring holder, and nine points were selected for sample scanning. The samples included: a blank sample (a substrate without any sample coating), a sample of the base makeup test plate, and a sample of the base makeup test plate after cleaning.

[0062] 4. SPF290S Data Processing Method

[0063] The scanning wavelength range is 290nm-400nm, and the scanning interval is 2nm. The transmittance at a single wavelength is taken as the average of 9 points. The cleaning power is calculated using the transmittance at the entire wavelength, which is calculated by summing the transmittance at a single wavelength and dividing by 56.

[0064] Example 1

[0065] 1. Sample preparation

[0066] Purchase foundation A as a typical example of a base makeup product.

[0067] Purchase multiple commercially available makeup removal products: Makeup Remover Oil #1, Makeup Remover Oil #2, Makeup Remover Oil #3, Makeup Remover Oil #4, Makeup Remover Balm #5, Makeup Remover Balm #6, Makeup Remover Balm #7, Makeup Remover Wipes #8.

[0068] 2. Preparation of instruments

[0069] Turn on the SPF290S sun protection factor meter and complete the instrument's self-test. Set the instrument parameters as follows: reference scan is single-point scan, and the number of sample scan points is 9. Place the uncoated PMMA plate on the measuring holder and select the center point for the reference scan.

[0070] 3. Determination of T0

[0071] A PMMA plate without any sample coating was used as a blank sample and its transmittance was measured on an SPF290S measuring holder. This transmittance was recorded as the transmittance of the substrate and denoted as T0.

[0072] 4. Preparation of the base makeup test plate

[0073] Place the PMMA plate with completed T0 determination on a balance. Using a syringe, evenly drop 50 mg (±2.5%) of foundation liquid A onto the 5 cm × 5 cm PMMA plate, adding the sample in a dotted manner. After pre-saturating the finger with foundation liquid A, evenly spread the dotted sample onto the substrate. After sample application, place the base makeup test plate at room temperature for 30 minutes to form a film.

[0074] 5. Determination of T1

[0075] The prepared base makeup test plate was placed on the SPF290S measuring holder and its transmittance was measured. This transmittance was recorded as T1.

[0076] 6. Cleaning the foundation test plate

[0077] Place the completed T1 test PMMA plate on a balance. Using a syringe, evenly drop 500 mg (±2.5%) of makeup remover oil #1 onto the PMMA plate. Clean the test plate according to the product instructions. After cleaning, gently wipe the back of the plate with a tissue to remove moisture, and then allow the test plate to dry at room temperature for 30 minutes.

[0078] 7. Determination of T2

[0079] The cleaned base makeup test plate was placed on the SPF290S measuring holder to measure its transmittance, which was taken as the transmittance of the cleaned base makeup test plate and denoted as T2.

[0080] 8. Processing of other samples

[0081] Several commercially available makeup removers were selected for testing. Other makeup removers were processed using the same steps to determine their transmittance. For makeup remover oil, a sample of 500 mg (±2.5%) was applied using a syringe. For makeup remover balm, a 500 mg (±2.5%) sample was weighed using the subtraction method, placed in the palm of the hand, rubbed, and then transferred to a PMMA plate for cleaning. For makeup remover water, a cotton pad was used to apply the sample, and the area was gently wiped clean, repeating multiple times until clean. All cleaning processes were performed according to the product instructions.

[0082] 9. SPF290S Data Processing Method

[0083] The SPF290S instrument has a scanning wavelength range of 290nm-400nm and a scanning interval of 2nm. The transmittance at a single wavelength is taken as the average of 9 points. The cleaning power is calculated using the transmittance across the entire wavelength range, which is calculated by summing the transmittance at a single wavelength and dividing by 56.

[0084] 10. Calculation of cleaning power

[0085]

[0086] In the formula:

[0087] X – Cleansing power of the makeup remover, %;

[0088] T0—Light transmittance of the substrate;

[0089] T1 – Light transmittance of the foundation test panel;

[0090] T2 – Light transmittance of the test plate after cleaning the base makeup.

[0091] 11. The result of cleaning power

[0092] The results of the cleansing power of the makeup remover on foundation A are shown in the table below (Table 1).

[0093] Table 1: Cleansing power results of makeup remover products on foundation A

[0094]

[0095] Compare with Example 1

[0096] 1. Sample preparation

[0097] Purchase foundation A as a typical example of a base makeup product.

[0098] Purchase multiple commercially available makeup removal products: Makeup Remover Oil #1, Makeup Remover Oil #2, Makeup Remover Oil #3, Makeup Remover Oil #4, Makeup Remover Balm #5, Makeup Remover Balm #6, Makeup Remover Balm #7, Makeup Remover Wipes #8.

[0099] 2. Preparation of instruments

[0100] Turn on the CR-300 colorimeter and use a standard white plate to calibrate the instrument. During the measurement, the sample plate is always placed on the standard white plate for each parameter measurement. Five points are selected on the PAAM plate for measurement, and the average value of L, a, and b at the five points is used to calculate ΔE.

[0101] 3. Determination of blank samples

[0102] Using an uncoated PMMA plate as a blank sample, the L, a, and b values ​​were measured using a CR-300 colorimeter and recorded as L0, a0, and b0.

[0103] 4. Preparation of the base makeup test plate

[0104] Place the PMMA plate with completed T0 determination on a balance. Using a syringe, evenly drop 50 mg (±2.5%) of foundation liquid A onto the 5 cm × 5 cm PMMA plate, adding the sample in a dotted manner. After pre-saturating the finger with foundation liquid A, evenly spread the dotted sample onto the substrate. After sample application, place the base makeup test plate at room temperature for 30 minutes to form a film.

[0105] 5. Determination of samples after application

[0106] The L, a, and b values ​​of the prepared base makeup test plate were measured using a CR-300 colorimeter and denoted as L1, a1, and b1.

[0107] 6. Cleaning the foundation test plate

[0108] Place the PMMA plate used for the above tests on a balance. Using a syringe, evenly drop 500 mg (±2.5%) of makeup remover oil #1 onto the PMMA plate. Clean the base makeup test plate according to the product instructions. After cleaning, gently wipe the back of the plate with a tissue to remove moisture. Place the cleaned base makeup test plate at room temperature to dry for 30 minutes.

[0109] 7. Determination of samples after cleaning

[0110] The cleaned base makeup test plate was tested using a CR-300 colorimeter, and its L, a, and b values ​​were measured and recorded as L2, a2, and b2.

[0111] 8. Processing of other samples

[0112] Several commercially available makeup removers were selected for testing. Other makeup removers were processed using the same steps to determine their transmittance. For makeup remover oil, a sample of 500 mg (±2.5%) was applied using a syringe. For makeup remover balm, a 500 mg (±2.5%) sample was weighed using the subtraction method, placed in the palm of the hand, rubbed, and then transferred to PMMA for washing. For makeup remover water, a cotton pad was used to apply the sample, and the area was gently wiped clean, repeating multiple times until clean. All washing processes were performed according to the product instructions.

[0113] 9. Calculation of ΔE

[0114]

[0115] 10. Calculation of cleaning power

[0116]

[0117] 11. The result of cleaning power

[0118] The results of the cleansing power of the makeup remover on foundation A are shown in Table 2 below.

[0119] Table 2: Cleansing power results of makeup remover products on foundation A

[0120]

[0121]

[0122] 12. Comparison of cleaning power results between Example 1 and Control Example 1

[0123] The results of the two groups of cleaning power, Example 1 and Control Example 1, are shown in Table 3. The correlation coefficient is 0.99, which shows that the method of evaluating the cleaning power of makeup remover products in vitro for the first time using the SPF290S sun protection index meter described in this invention is consistent with the results of the common evaluation method using color difference ΔE.

[0124] Table 3: Cleansing power results of makeup remover products on foundation A

[0125]

Claims

1. An in vitro evaluation method for the makeup remover's ability to remove base makeup, comprising the following steps: (1) Provide testing equipment: SPF290S sun protection index meter; (2) Substrate provided: PMMA board; (3) Measure the transmittance T0 of the substrate; (4) Preparation of the base makeup test plate: Apply the base makeup product evenly to the substrate; (5) Measure the light transmittance T1 of the base makeup test plate; (6) Clean the base makeup test plate: Clean the base makeup test plate with makeup remover; (7) Measure the light transmittance T2 of the base makeup test plate after cleaning; (8) Calculate cleaning power: In the formula: X – Cleansing power of the makeup remover, %; T0—Light transmittance of the substrate; T1 – Light transmittance of the foundation test panel; T2 – Light transmittance of the test plate after cleaning the base makeup.

2. The in vitro evaluation method as described in claim 1, wherein, In step (2), the PMMA has a size of 5cm*5cm and a roughness of 5μm.

3. The in vitro evaluation method as described in claim 1, wherein, In step (4), the amount of foundation product applied is 2 mg / cm³. 2 .

4. The in vitro evaluation method as described in claim 1, wherein, After completing step (4), place the base makeup test plate at room temperature to form a film.

5. The in vitro evaluation method as described in claim 4, wherein, The film formation time is 30 minutes.

6. The in vitro evaluation method as described in claim 1, wherein, The cleaning method in step (6) should be followed according to the product instructions. The amount of makeup remover used is 20mg / cm³. 2 .

7. The in vitro evaluation method as described in claim 1, wherein, After cleaning in step (6), gently wipe the back of the board with a paper towel to remove moisture, and place the base makeup test board at room temperature to dry.

8. The in vitro evaluation method as described in claim 7, wherein, The drying time is 30 minutes.

9. The in vitro evaluation method as described in claim 1, wherein, The SPF290S instrument has a scanning wavelength range of 290nm-400nm and a scanning interval of 2nm.

10. The in vitro evaluation method as described in claim 1, wherein, The makeup removal products are selected from: makeup remover oil, makeup remover balm, makeup remover water, or makeup remover wipes.

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