A kind of artificial skin for sensory evaluation and preparation method thereof

Abstract

The present invention provides a simulated skin for sensory evaluation and a preparation method thereof. The simulated skin is provided with a substrate and a lipid surface layer applied on the surface of the substrate, simulating the epidermal structure and sebum membrane structure of a real human body, and can replace real human skin for cosmetic sensory evaluation testing. The simulated skin can reduce the impact of differences in skin conditions of different sensory evaluators on sensory evaluation test results, and can also reduce the potential risk of cosmetics causing human allergies. Without increasing the number of evaluators, the data of sensory evaluation test results are greatly enriched, the technical requirements of sensory evaluation are fully met, and labor costs are saved. The preparation method of the simulated skin for sensory evaluation of the present invention comprises the step of applying grease on the surface of the substrate. The preparation method has simple steps, and the key steps of simulating human skin are reasonably arranged, and a simulated skin product suitable for cosmetic sensory evaluation can be produced.

Description

Technical Field

[0001] The invention relates to the technical field of cosmetic sensory evaluation, in particular to a simulated skin for sensory evaluation and a preparation method thereof. Background Art

[0002] In the field of cosmetics, sensory evaluation usually involves applying the product to be tested directly to human skin, and relying on the subjective feelings of the human body to evaluate the sensory performance of the product. Since the evaluation is performed on the evaluator's own skin, and the skin conditions of different individuals vary greatly, and each evaluator has a limited skin area suitable for evaluation, in order to achieve accurate and effective sensory evaluation results, it is necessary to increase the number of evaluations and the number of evaluators, which prolongs the test time and increases the amount of data processing in the later stage, resulting in a significant increase in manpower and time costs. In addition, sensory evaluation requires the product to be tested to be applied to the surface of human skin for testing, which increases the risk of skin sensitization. The problems existing in the sensory evaluation of cosmetics have affected the promotion and application of sensory evaluation technology in the industry.

[0003] Existing bionic skin is mostly used in the field of medical devices and tissue engineering materials, that is, it mainly helps the delivery of nutrients and promotes the healing of skin wounds, etc. It does not involve the reconstruction of epidermal texture and water-oil ratio. The water-oil distribution and elastic touch of its epidermis are quite different from the real epidermis of the human body, and cannot be applied to the sensory evaluation of the sensory experience of cosmetic application. Even in the field of cosmetics, the current application of bionic skin is mainly focused on the study of the mechanism of the effect of cosmetic raw materials on the skin. This application only simulates the internal structure of the skin and explores the mechanism of action of cosmetic raw materials inside the skin, and cannot be applied to the sensory evaluation of applied cosmetics.

[0004] Therefore, in view of the shortcomings of the prior art, it is necessary to provide a simulated skin for sensory evaluation and a preparation method thereof to overcome the shortcomings of the prior art. Summary of the invention

[0005] One of the purposes of the present invention is to avoid the shortcomings of the prior art and provide a simulated skin for sensory evaluation. The simulated skin can truly simulate the epidermal structure and sebum membrane structure of real human skin, and can be used in cosmetic sensory evaluation as a substitute for cosmetic sensory evaluation tools.

[0006] The above-mentioned purpose of the present invention is achieved through the following technical measures.

[0007] Provided is a simulated skin for sensory evaluation, which is a simulated skin imitating human skin and is prepared by a process at least comprising the step of applying oil on the surface of a substrate. The simulated skin is consistent with human skin.

[0008] Specifically, the simulated skin for sensory evaluation is provided with a base and a lipid surface layer applied on the surface of the base.

[0009] The matrix comprises a base layer and an elastic layer coated and solidified on the surface of the base layer, and the lipid surface layer is located on the surface of the elastic layer.

[0010] Specifically, the lipid surface layer comprises, by weight: 5 to 100 parts of triglycerides, 1.5 to 40 parts of squalene, 0.6 to 20 parts of fatty acids, and 5 to 200 parts of emulsifiers.

[0011] Preferably, the lipid surface layer further comprises, by weight: 2.5 to 50 parts of wax ester, 0.2 to 20 parts of cholesterol, 0.1 to 5 parts of antioxidant, 100 to 1000 parts of water, and a pH regulator that makes the pH value of the simulated skin range from 4.5 to 6.5.

[0012] More preferably, the lipid surface layer comprises, by weight: 40-60 parts of triglycerides, 10-20 parts of squalene, 4.8-10 parts of fatty acids, 40-60 parts of emulsifiers, 20-30 parts of wax esters, 1.6-5 parts of cholesterol, 1-5 parts of antioxidants, and 500-1000 parts of water.

[0013] Preferably, the triglyceride is at least one of caprylic / capric triglyceride, glyceryl tripelargonate, and glyceryl trioleate;

[0014] The wax ester is at least one of jojoba oil, palm wax, candelilla wax and beeswax;

[0015] The fatty acid is at least one of palmitic acid, lauric acid and myristic acid;

[0016] The antioxidant is at least one of tocopherol acetate, di-tert-butyl-p-cresol, and tert-butyl hydroxyanisole;

[0017] The emulsifier is at least one of coconut glucoside, cetearyl glucoside and arachidyl glucoside;

[0018] The pH regulator is lactic acid.

[0019] Preferably, the base layer is a spunlace nonwoven fabric, and the elastic layer is a polyurethane resin layer.

[0020] The simulated skin for sensory evaluation of the present invention is provided with a base and a lipid surface layer applied on the surface of the base. The base of the simulated skin of the present invention simulates the epidermal structure of a real human body, and the lipid surface layer on the surface of the base simulates the sebum membrane structure of a real human body. Compared with the bionic skin in the field of tissue engineering materials, the simulated skin can simulate the physical properties of the real human epidermis and can replace the real human skin for cosmetic sensory evaluation tests. As a substitute for real human skin in cosmetic sensory evaluation, the simulated skin can reduce the impact of the differences in skin conditions of different sensory evaluators on the sensory evaluation test results, and can also reduce the potential risk of cosmetics causing human allergies.

[0021] Another object of the present invention is to avoid the shortcomings of the prior art and provide a method for preparing simulated skin for sensory evaluation. The method is simple to operate, has reasonable key control steps, can mass-produce simulated skin suitable for sensory evaluation with stable performance, and has low production cost.

[0022] The above-mentioned purpose of the present invention is achieved through the following technical measures.

[0023] Provided is a method for preparing simulated skin for sensory evaluation, which comprises the step of applying grease on the surface of a substrate.

[0024] Specifically, the method for preparing the simulated skin for sensory evaluation comprises the following steps:

[0025] Step 1: prepare a substrate.

[0026] Step 2: Coloring the base to simulate human skin color.

[0027] Step three, embossing the colored substrate to imitate the pore texture of the human body.

[0028] Step 4: Wash and dry the colored and embossed substrate to obtain a substrate simulating the skin color and pore texture of human skin.

[0029] Step 5, detecting whether the friction coefficient of the substrate surface obtained in step 4 is within the target friction coefficient range. When the measured friction coefficient is within the target friction coefficient range, proceed to step 6; otherwise, changing the depth of the human pore-simulating texture on the pattern roller to re-emboss the substrate until the friction coefficient of the substrate surface meets the target friction coefficient range, and proceeding to step 6.

[0030] Step six, applying a lipid surface layer on the surface of the elastic layer of the substrate whose friction coefficient meets the target friction coefficient range requirements to obtain a finished simulated skin.

[0031] Specifically, in the above step 1, the step of preparing the substrate includes:

[0032] Evenly apply the pre-formulated polyurethane resin slurry on the base layer and spread the slurry with a squeeze roller.

[0033] The slurry is uniformly coagulated on the base layer through a water coagulation tank to obtain unmodified polyurethane artificial leather.

[0034] Specifically, the target friction coefficient of the simulated skin for sensory evaluation is in the range of 0.4 to 0.6.

[0035] The preparation method of the simulated skin for sensory evaluation of the present invention comprises the step of applying grease on the surface of a substrate. The preparation method applies grease on the surface of a substrate whose pore pattern, color and friction coefficient have been adjusted, and can simulate the epidermal structure and sebum membrane structure of real human skin. The preparation method has simple steps, and the key steps of simulating human skin are reasonably arranged, and can produce a simulated skin product suitable for the sensory evaluation of cosmetics. DETAILED DESCRIPTION

[0036] The present invention will be further described with reference to the following examples.

[0037] Example 1.

[0038] A simulated skin for sensory evaluation is prepared by a process including at least the step of applying oil simulating human skin surface lipids on the surface of a base body, and the simulated skin is consistent with human skin. The simulated skin for sensory evaluation is provided with a base body and a lipid surface layer applied on the surface of the base body. The base body includes a base layer and an elastic layer coated and solidified on the base layer, and the lipid surface layer is located on the surface of the elastic layer.

[0039] The surface friction coefficient of the simulated skin ranges from 0.4 to 0.6, and the pH value ranges from 4.5 to 6.5. The simulated skin truly simulates the skin color, texture, friction, pH value, elastic touch and other properties of human skin, and can be used in cosmetic sensory evaluation as a substitute for cosmetic sensory evaluation tools.

[0040] The base layer of this embodiment can be a spunlace nonwoven fabric. Spunlace nonwoven fabric is a product with a strong mesh structure formed by the process of "jet spunlace to fabric". The spunlace nonwoven fabric is soft in texture, has high hygroscopicity and quick wetting, high fabric strength, washable and not easy to mildew, and is an excellent support.

[0041] The elastic layer of this embodiment can be a polyurethane resin layer. In parts by weight, the elastic layer includes: 85-115 parts of polyurethane resin, 15-35 parts of wood powder, 50-80 parts of dimethylformamide (DMF), and 15-35 parts of color powder. The elastic layer prepared with this ratio has a soft texture and meets the performance requirements of human epidermis.

[0042] The simulated skin base part prepared by combining the above-mentioned base layer and elastic layer has the characteristics of wear resistance and washing resistance. After cleaning and re-applying grease, its performance remains the same as before, and it can be recycled in the cosmetic sensory evaluation test, solving the problem that real human skin is prone to fatigue during frequent application of cosmetics and cleaning. At the same time, it reduces the risk of allergy caused by cosmetics to real human skin. In addition, the elastic layer made of polyurethane resin also has hygroscopicity, moisture permeability and elasticity, so that after the simulated skin comes into contact with cosmetics, it can simulate the absorption process of cosmetics by real human skin.

[0043] The lipid surface layer includes, by weight: 5-100 parts of triglycerides, 1.5-40 parts of squalene, 0.6-20 parts of fatty acids, and 5-200 parts of emulsifiers. Preferably, the lipid surface layer also includes: 2.5-50 parts of wax esters, 0.2-20 parts of cholesterol, 0.1-5 parts of antioxidants, 100-1000 parts of water, and a pH regulator that makes the pH value of the simulated skin range from 4.5 to 6.5.

[0044] Among them, triglyceride can be selected from at least one of caprylic / capric triglyceride, glyceryl tripelargonate, and glyceryl trioleate. Wax ester can be selected from at least one of jojoba oil, palm wax, candelilla wax, and beeswax. Fatty acid can be selected from at least one of palmitic acid, lauric acid, and myristic acid. Antioxidant can be selected from at least one of tocopherol acetate, di-tert-butyl paracresol, and tert-butyl hydroxyanisole. Emulsifier can be selected from at least one of coconut oil glucoside, cetearyl glucoside, and arachidyl glucoside. pH regulator can be selected from lactic acid. The lipid surface layer in this embodiment can be prepared using commercially available raw materials, and those skilled in the art can select suitable raw materials according to actual needs, which will not be listed here one by one.

[0045] The lipid surface layer is a kind of oil that simulates the sebum on the surface of real human skin. The oil can adjust the water-oil distribution and pH value on the surface of the substrate so that the above performance parameters are consistent with the state of real human skin.

[0046] The simulated skin for sensory evaluation of the present invention is provided with a base layer, an elastic layer coated and solidified on the base layer, and a lipid surface layer applied on the surface of the elastic layer. Among them, the spunlace non-woven fabric is used as the base layer to form a support surface. The polyurethane resin is used as the elastic layer to simulate the skin color, texture, friction and elastic touch of human skin. The oil simulating the sebum lipids on the surface of human skin is used as the lipid surface layer to simulate the sebum membrane of human skin. The present invention stacks the base layer, the elastic layer and the lipid surface layer in sequence, which can simulate the skin color, texture, friction and elastic touch of real human skin. Therefore, the simulated skin for sensory evaluation of the present invention can be used to test the sensory evaluation indicators such as the ease of application, whitening, coverage, skin brightness, skin stickiness, etc. of cosmetics after being applied to human skin. The sensory evaluation test effect of the simulated skin is close to the test effect of real human skin, avoiding the fatigue caused by long-term sensory testing with human skin and the safety problem of cosmetics causing allergic risks to human skin, and can be used as a substitute for real human skin in sensory testing.

[0047] Example 2.

[0048] A simulated skin for sensory evaluation, the other structures and materials are the same as those of Example 1, except that the lipid surface layer of this embodiment includes, by weight: 40-60 parts of triglycerides, 10-20 parts of squalene, 4.8-10 parts of fatty acids, 40-60 parts of emulsifiers, 20-30 parts of wax esters, 1.6-5 parts of cholesterol, 1-5 parts of antioxidants, 500-1000 parts of water, and a pH regulator that makes the pH value of the simulated skin range from 4.5 to 6.5.

[0049] In the lipid surface layer of this embodiment, the ratio of oils and fats simulating the sebum lipids on the surface of human skin is closer to the pH value and water-oil distribution of real human skin, thereby improving the accuracy of the cosmetic sensory evaluation test results.

[0050] The simulated skin of the present invention is a cosmetic sensory evaluation tool that can test sensory evaluation indicators such as ease of application, whitening, coverage, skin brightness, and skin stickiness of cosmetics after they are applied to human skin. The sensory evaluation test effect of the simulated skin is close to that of real skin, avoiding the fatigue caused by long-term sensory testing with human skin and the safety problem of cosmetics causing allergic reactions to human skin, and can be used as a substitute for sensory test objects.

[0051] Example 3.

[0052] A method for preparing simulated skin for sensory evaluation as in Example 1 or 2 comprises the step of applying oil simulating sebum on the surface of human skin to the surface of a substrate.

[0053] The method for preparing the simulated skin for sensory evaluation specifically comprises the following steps:

[0054] Step 1, preparing the substrate. Specifically, the pre-formulated polyurethane resin slurry is coated on the base layer, the slurry is rolled down to a thickness of 0.1 to 0.3 mm by an extrusion roller, and the slurry is uniformly solidified on the base layer through a water solidification tank to obtain an unmodified polyurethane artificial leather.

[0055] Step 2: coloring the base to simulate human skin color. Specifically, the color powder is mixed into a color paste according to the required skin color ratio, the color paste temperature is maintained between 45°C and 50°C, and is coated on the polyurethane resin layer of the unmodified polyurethane artificial leather obtained in step 1 by a roller.

[0056] Step 3: embossing the colored substrate with a human pore texture. Specifically, the colored polyurethane artificial leather obtained in step 2 is pulled through a pattern roller with a human pore texture to obtain a polyurethane artificial leather with a human skin pore texture.

[0057] Step 4: Wash and dry the colored and embossed substrate to obtain a substrate simulating the skin color and pore texture of human skin. Specifically, the colored and embossed polyurethane artificial leather obtained in step 3 is passed through a washing tank to replace the solvent inside the polyurethane artificial leather with water, thereby forming a porous film, and then dried at 120° C. to finally form a polyurethane artificial leather simulating the skin color and pore texture of human skin.

[0058] Step 5: Check whether the friction coefficient of the substrate surface obtained in step 4 is within the target friction coefficient range. If the measured friction coefficient is within the target friction coefficient range, proceed to step 6; otherwise, change the depth of the human pore texture on the pattern roller to re-emboss the substrate until the friction coefficient of the substrate surface meets the target friction coefficient range, and proceed to step 6. It should be noted that the target friction coefficient range is 0.4 to 0.6. This friction coefficient range truly simulates the friction index requirements of human skin.

[0059] Step six, smearing oil simulating sebum on the surface of the elastic layer of the substrate whose friction coefficient meets the target friction coefficient range as a lipid surface layer to obtain a finished simulated skin.

[0060] In view of the requirement of simulating the state of real human skin, the key control points of the simulated skin preparation method of this embodiment are the color adjustment of the base and the adjustment of the surface friction coefficient, so as to simulate the key parameters such as skin color, texture, friction coefficient and so on of real human skin, and can provide an effective evaluation test tool alternative for the sensory evaluation of cosmetics.

[0061] The preparation method of the present invention is simple to operate, the key control steps are reasonably set, the production efficiency is high, and the simulated skin products with stable performance for sensory evaluation can be mass-produced, and the production cost is low. Since the quality and performance of the simulated skin products are stable, the simulated skins prepared in the same batch have consistent performance in parameters such as skin color, texture, friction, pH, and elastic touch, which can solve the problem of sensory evaluation test result errors caused by individual differences in the skin of evaluators.

[0062] Since the test area for cosmetic sensory evaluation is not large, the simulated skin produced by the preparation method of the present invention can be cut into sheets with smaller areas and supplied in large quantities for cosmetic sensory evaluation testing. At the same time, the preparation method of the present invention is flexible and convenient for controlling product performance and can simulate skin of different ages, different races, and different parts. Without increasing the number of evaluators, the data of sensory evaluation test results is greatly enriched, fully meeting the technical requirements of sensory evaluation.

[0063] Example 4.

[0064] A simulated skin prepared by the method for preparing a simulated skin for sensory evaluation of Example 2, wherein the other steps are the same as those of Example 2, except that:

[0065] In this embodiment, the elastic layer of the prepared simulated skin includes, by weight, 100 parts of polyurethane resin, 25 parts of wood powder, 65 parts of dimethylformamide (DMF), and 25 parts of color powder.

[0066] In this embodiment, the base layer of step one is made of Huahao brand spunlace non-woven fabric, and the ratio of viscose to polyester is 3:7.

[0067] In this embodiment, the pre-formulated polyurethane resin slurry in step one includes polyurethane resin (selected from htresin brand, model Dolphin-1378, solid content 35±2%), wood powder (selected from Xingdong brand, special white powder) and dimethylformamide (DMF for short, selected from Hualu Hengsheng brand, industrial grade, content ≥99%).

[0068] The thickness of the polyurethane resin layer prepared in this embodiment is about 0.2 mm, which truly simulates the average epidermal thickness in the skin structure of the human face, limbs, etc. Therefore, the simulated skin prepared by the simulated skin preparation method of the present invention can be used in the cosmetic sensory evaluation test, and can test the ease of application, whitening, coverage, skin brightness, skin stickiness and other index parameters of the cosmetics after they are applied to the human skin through the skin testing instrument.

[0069] In this embodiment, step 2 specifically comprises mixing red, yellow and white toners in a mass ratio of 1:1:3 into a color paste, maintaining the color paste temperature at 45°C-50°C, and coating the color paste on the polyurethane resin layer of the unmodified polyurethane artificial leather obtained in step 1 by a roller. Among them, the red toner is acid fuchsin 6B (selected from Tianjin Yazhong brand, industrial grade), the yellow toner is acid tender yellow 2G (selected from Tianjin Yazhong brand, industrial grade), and the white toner is rutile titanium dioxide (selected from Shandong Jinpu brand, industrial grade).

[0070] The color powder composition and proportion of this embodiment can produce a simulated skin that truly simulates the yellowish skin color of Asians. It should be noted that even among Asians, there are some differences in skin color. For example, the skin color of Asians in East Asia is white, and the skin color of Asians in South Asia is dark yellow to brown. Those skilled in the art can mix and match the appropriate skin color as needed in actual applications, and the color powder mixing ratios are not listed here one by one. Similarly, if other skin colors need to be simulated, the color powders can be mixed and matched as needed.

[0071] The preparation method of the artificial skin for sensory evaluation of the present invention has simple steps and the quality of the finished product is stable. The artificial skin prepared in the same batch has consistent performance in parameters such as skin color, texture, friction and elastic touch, which can solve the problem of sensory evaluation test effect error caused by individual differences in the skin of evaluators.

[0072] Example 5.

[0073] Comparative experiment on cosmetic sensory evaluation of the simulated skin of the present invention and real human skin

[0074] 1 Experimental Purpose

[0075] The simulated skin of the present invention and real human skin are used as cosmetic sensory evaluation tools, and the differences between the two are compared in terms of sensory evaluation indicators such as ease of application, whitening, coverage, skin brightness, and skin stickiness.

[0076] 2 Experimental Preparation

[0077] In this embodiment, the method of Example 4 was used to prepare simulated skin samples 1 to 9. The other structures and materials of these 9 samples are the same as those of Example 1, except that in samples 1 to 9, the oils used as the lipid surface layer are prepared according to the ratio of Table 1. In this embodiment, the triglyceride is caprylic / capric triglyceride (British Croda brand, cosmetic grade, content ≥99%), the wax ester is jojoba oil (Jiangxi Baolin brand, cosmetic grade, content ≥95%), the fatty acid is palmitic acid (Malaysian Emuri brand, cosmetic grade, content ≥99%), the antioxidant is tocopherol acetate (German BASF brand, cosmetic grade, content ≥98%), and the emulsifier is MONTANOV containing coconut oil glucoside. TMS (French Seppic brand, cosmetic grade, content ≥99%), pH regulator is lactic acid (Henan Jindan brand, cosmetic grade, content ≥80%), squalene is Shaanxi Jiahe Biological brand (cosmetic grade, content ≥80%), and cholesterol is American McLean brand (SigmaGrade, content ≥99%).

[0078] Table 1 Component ratio of lipid surface layer in simulated skin (unit: weight parts)

[0079]

[0080] 3 Experimental steps

[0081] The cosmetics used for the test were sample 374 (Cruya Brightening Essence) and sample 591 (Cruya Whitening Lotion), and the sensory evaluation indicators of the test were ease of application, whitening, coverage, skin brightness and skin stickiness.

[0082] The test is divided into two groups: the first group consists of 7 professionally trained evaluators who conduct sensory evaluation of the cosmetics on the inner skin of their own arms, use instruments for verification, and record the instrument verification scores; the second group consists of evaluators who apply the cosmetics on the surface of simulated skin samples 1 to 9 for sensory evaluation, use instruments for verification, and record the instrument verification scores.

[0083] The evaluation methods, scoring criteria and instrument verification methods for each sensory evaluation index are shown in Table 2.

[0084] Table 2 Evaluation methods, scoring criteria and instrument verification methods for sensory evaluation indicators

[0085]

[0086] 4 Experimental results

[0087] The sensory evaluation results of samples 374 and 591 in this experiment are shown in Tables 3 and 4.

[0088] Table 3 Sensory evaluation results of sample 374

[0089] Sensory evaluation index Difficulty of application Whitening Coverage Skin radiance Skin stickiness Reviewer 1 12.2 3.9 2.5 7.6 8.4 Reviewer 2 12.5 3.9 2.5 7.3 7.8 Reviewer 3 12.5 3.8 2.3 7.2 8.0 Reviewer 4 12.4 3.2 2.8 7.6 7.8 Reviewer 5 12.7 3.7 2.3 7.3 7.5 Reviewer 6 12.5 3.5 2.1 7.5 8.5 Reviewer 7 12.6 3.7 2.8 7.7 8.0 The average value of 7 evaluators is Xi 12.5 3.7 2.5 7.5 8.0 Sample 1 11.9 3.1 1.8 6.7 7.5 Sample 2 12.1 3.4 2.1 6.6 7.5 Sample 3 12.2 3.2 2.4 6.9 7.4 Sample 4 12.1 3.1 2.1 7.3 7.6 Sample 5 12.4 3.7 2.3 7.2 8.0 Sample 6 12.4 3.6 2.4 7.6 8.2 Sample 7 12.7 3.9 2.8 7.9 8.2 Sample 8 13.2 4.4 3.3 8.1 8.6 Sample 9 13.1 4.5 3.2 8.3 8.5

[0090] Table 4 Sensory evaluation results of sample 591

[0091] Sensory evaluation index Difficulty of application Whitening Coverage Skin radiance Skin stickiness Reviewer 1 10.0 9.7 7.3 7.6 7.3 Reviewer 2 10.3 9.2 6.2 7.8 8.4 Reviewer 3 10.5 9.3 6.2 8.7 8.6 Reviewer 4 10.1 9.7 7.3 8.4 8.1 Reviewer 5 10.5 9.2 6.6 7.5 8.5 Reviewer 6 10.6 9.5 7.5 8.5 7.8 Reviewer 7 10.2 9.0 6.6 7.4 7.4 The average value of 7 evaluators is Xi 10.3 9.4 6.8 8.0 8.0 Sample 1 9.2 9.0 6.2 7.8 7.3 Sample 2 9.5 9.4 7.6 8.0 7.5 Sample 3 9.8 9.5 6.1 8.0 7.4 Sample 4 9.8 9.5 7.5 7.8 7.2 Sample 5 10.2 9.8 6.4 8.1 7.9 Sample 6 10.1 9.7 6.7 7.6 8.3 Sample 7 10.4 9.4 6.8 8.4 8.2 Sample 8 10.9 10.3 7.7 8.9 8.8 Sample 9 11.1 10.2 7.5 8.9 8.7

[0092] 5 Results Analysis

[0093] The average value Xi is taken from the sensory evaluation test data of real human skin of 7 evaluators, and the range of plus or minus 1 of the average value Xi is defined as the sensory evaluation test result conforming to the sensory evaluation effect of real human skin. Among them, i represents the ease of application, whitening degree, coverage, skin brightness or skin stickiness.

[0094] From the sensory evaluation test results in Tables 3 and 4, it can be seen that the lipid surface layer composition of the simulated skin of the present invention is within the range of 5-100 parts of triglycerides, 1.5-40 parts of squalene, 0.6-20 parts of fatty acids, 5-200 parts of emulsifiers, 2.5-50 parts of wax esters, 0.2-20 parts of cholesterol, 0.1-5 parts of antioxidants, 100-1000 parts of water, and a pH regulator that makes the pH value of the simulated skin range from 4.5 to 6.5, and its sensory evaluation test data all fall within the range of [Xi±1]. It is proved that the simulated skin samples 1 to 9 of this embodiment are close to the results measured by real human skin in the five sensory evaluation indicators of ease of application, whitening, coverage, skin brightness and skin stickiness after testing by various skin testing instruments. It shows that the simulated skin samples 1 to 9 of this embodiment can be applied to cosmetic sensory testing and can be used as substitutes for human skin.

[0095] Among them, the preferred ratio range of the lipid surface layer is: 40-60 parts of triesters, 10-20 parts of squalene, 4.8-10 parts of fatty acids, 40-60 parts of emulsifiers, 20-30 parts of wax esters, 1.6-5 parts of cholesterol, 1-5 parts of antioxidants, and 500-1000 parts of water. The test results of samples 5 to 7 prepared with the preferred ratio range for the lipid surface layer are closest to the average value Xi of the sensory evaluation test of the real human skin of each sensory evaluation index.

[0096] The simulated skin of the present invention is a cosmetic sensory evaluation tool, which can test sensory evaluation indicators such as whitening, coverage, skin brightness, and skin stickiness of cosmetics after they are applied to human skin. The sensory evaluation test effect of the simulated skin is close to the test effect of real skin, avoiding the fatigue caused by long-term sensory testing with human skin and the safety problem of cosmetics causing sensitization risks to human skin. It can be used as a substitute for sensory test objects, is suitable for promotion in the field of cosmetic sensory evaluation, is beneficial to promoting the development of cosmetic sensory evaluation technology, and has broad market prospects.

[0097] Example 6.

[0098] Comparison of cosmetic sensory evaluation between the simulated skin of the present invention and the substrate of the present invention without grease applied on the surface experiment

[0099] 1 Experimental Purpose

[0100] The simulated skin of the present invention and the substrate of the present invention without grease applied on the surface were used as cosmetic sensory evaluation tools, and the differences between the two were compared in terms of sensory evaluation indicators such as ease of application, whitening, coverage, skin brightness, and skin stickiness.

[0101] 2 Experimental Preparation

[0102] Simulated skin samples 1 to 6 were prepared as in Example 5.

[0103] The process of step 1 to step 5 of this embodiment 4 was used to prepare comparative examples 1, 2 and 3. Comparative examples 1, 2 and 3 were substrates that were not greased. The surface friction coefficient of comparative example 1 was 0.43, the surface friction coefficient of comparative example 2 was 0.52, and the surface friction coefficient of comparative example 3 was 0.59.

[0104] 3 Experimental steps

[0105] The cosmetics used for testing were sample 374 and sample 591, and the sensory evaluation indicators of the test were ease of application, whitening, coverage, skin brightness and skin stickiness.

[0106] The evaluator applies the cosmetics on the surfaces of Comparative Examples 1 to 3 for sensory evaluation, uses instrument verification, and records the instrument verification scores.

[0107] The evaluation methods, scoring criteria and instrument verification methods for each sensory evaluation index are shown in Table 2 of Example 5.

[0108] 4 Experimental results

[0109] The sensory evaluation results of samples 374 and 591 in this experiment are shown in Tables 5 and 6.

[0110] Table 5 Sensory evaluation test data of sample 374 on simulated skin and ordinary polyurethane artificial leather

[0111] Sensory evaluation index Difficulty of application Whitening Coverage Skin radiance Skin stickiness Comparative Example 1 11.1 1.9 1.2 10.5 11.0 Comparative Example 2 11.4 1.8 1.0 10.8 11.6 Comparative Example 3 13.8 2.5 3.7 10.0 11.4 The average value of 7 evaluators is Xi 12.5 3.7 2.5 7.5 8.0

[0112] Table 6 Sensory evaluation test data of sample 591 on simulated skin and ordinary polyurethane artificial leather

[0113] Sensory evaluation index Difficulty of application Whitening Coverage Skin radiance Skin stickiness Comparative Example 1 12.2 6.0 5.1 12.0 10.1 Comparative Example 2 12.5 6.5 5.0 11.6 10.5 Comparative Example 3 11.7 7.1 5.2 11.5 10.0 The average value of 7 evaluators is Xi 10.3 9.4 6.8 8.0 8.0

[0114] 5 Results Analysis

[0115] The average value Xi is taken from the sensory evaluation test data of real human skin of 7 evaluators, and the range of plus or minus 1 of the average value Xi is defined as the sensory evaluation test result conforming to the sensory evaluation effect of real human skin. Wherein, i represents the ease of application, whitening degree, coverage, skin brightness or skin stickiness. The reference standard of this embodiment is the average value Xi of the sensory evaluation test of real human skin of 7 evaluators in Example 5.

[0116] The results show that, in Comparative Examples 1 to 3 of this embodiment, the substrates that have not been treated with grease, although their surface friction coefficients are in the range of the friction coefficients of real human skin, and the friction coefficients are between 0.4 and 0.6, their sensory evaluation test data deviate from the range of [Xi±1], that is, they do not meet the sensory evaluation effect of real human skin. As can be seen from Example 5, the cosmetic sensory evaluation test data of the simulated skin of the present invention is close to that of real human skin, thus proving that the substrates that have not been treated with grease do not meet the conditions for being used as cosmetic sensory evaluation test tools and cannot be used as substitutes for human skin.

[0117] Example 7.

[0118] Experimental study on the effect of the lipid surface oil composition of the simulated skin of the present invention on the sensory evaluation of cosmetics

[0119] 1 Experimental Purpose

[0120] An element reduction experiment was conducted on the lipid surface layer composition of the present invention to verify the importance of each component in the lipid surface layer of the present invention in simulating the effect of real human skin.

[0121] 2 Experimental Preparation

[0122] According to Example 4, simulated skin sample 10 and comparative examples 4 to 14 were prepared, wherein the lipid surface layer composition of each simulated skin was prepared according to the ratio in Table 7. This experiment used the lipid surface layer composition of the simulated skin sample 10 of the present invention as a reference basis.

[0123] Table 7 The ratio of oils and fats used to simulate the sebum on the surface of human skin in the simulated skin (unit: weight parts)

[0124]

[0125] 3 Experimental steps

[0126] The cosmetics used for testing were sample 374 and sample 591, and the sensory evaluation indicators of the test were ease of application, whitening, coverage, skin brightness and skin stickiness.

[0127] The test is divided into three groups: the first group consists of professionally trained evaluators performing sensory evaluation on the inner skin of their own arms, using instruments for verification, and recording the instrument verification scores; the second group consists of evaluators applying cosmetics to the surface of simulated skin sample 10 for sensory evaluation, using instruments for verification, and recording the instrument verification scores; the third group consists of evaluators applying cosmetics to the surfaces of simulated skin comparison samples 4 to 14 for sensory evaluation, using instruments for verification, and recording the instrument verification scores.

[0128] The evaluation methods, scoring criteria and instrument verification methods for each sensory evaluation index are shown in Table 2 of Example 5.

[0129] 4 Experimental results

[0130] The sensory evaluation results of samples 374 and 591 in this experiment are shown in Tables 8 and 9.

[0131] Table 8 Sensory evaluation test data of sample 374

[0132]

[0133] Table 9 Sensory evaluation test data of sample 591

[0134]

[0135] 5 Results Analysis

[0136] The sensory evaluation test data of real human skin is used as the reference value Zj. The range of Zj value plus or minus 1 is defined as the sensory evaluation test result is consistent with the sensory evaluation effect of real human skin. Among them, j represents the ease of application, whitening, coverage, skin brightness or skin stickiness.

[0137] From the results of Table 8 and Table 9, it can be seen that the sensory evaluation test data of the simulated skin sample 10 of the present invention all fall within the range of [Zj±1], which is consistent with the sensory evaluation effect of real human skin. The sensory evaluation test data of Comparative Examples 4 to 14 all have 2 to 5 sensory evaluation indicators that fail to meet the standards. Among them, the lipid surface layer composition lacks caprylic / capric triglyceride, squalene, palmitic acid and MONTANOV TM The five sensory evaluation indicators of Comparative Examples 11 to 14 of S emulsifier all failed to meet the standards and deviated greatly from the test data of real human skin. TM S emulsifier is an important component of the present invention for simulating the structure of human sebum membrane.

[0138] The lipid surface layer compositions of Comparative Examples 4 to 10 are designed with several additions of jojoba oil (wax ester), cholesterol, and tocopherol acetate (antioxidant). The sensory evaluation test data of Comparative Examples 4 to 10 do not fully meet the standards. Among the index data that do not meet the standards, the degree of deviation from the test data of real human skin is not as serious as that of Comparative Examples 11 to 14 that lack important components. Further explanation: caprylic / capric triglyceride (triglyceride), squalene, palmitic acid (fatty acid) and MONTANOV TM S emulsifier is an essential material for preparing simulated skin that can be used for sensory evaluation of cosmetics.

[0139] In summary, the simulated skin of the present invention is a cosmetic sensory evaluation tool that can test sensory evaluation indicators such as ease of application, whitening, coverage, skin brightness, and skin stickiness of cosmetics after they are applied to human skin. The sensory evaluation test effect of the simulated skin is close to the test effect of real skin, avoiding the fatigue caused by long-term sensory testing with human skin and the safety problem of cosmetics causing sensitization risks to human skin. It can be used as a substitute for sensory test objects, is suitable for promotion in the field of cosmetic sensory evaluation, is beneficial to promoting the development of cosmetic sensory evaluation technology, and has broad market prospects.

[0140] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A simulated skin for sensory evaluation, characterized in that: A substrate and a lipid surface layer applied on the surface of the substrate are provided; the substrate comprises a base layer and an elastic layer coated and solidified on the surface of the base layer, and the lipid surface layer is located on the surface of the elastic layer; The lipid surface layer comprises, by weight: 40-60 parts of triglycerides, 10-20 parts of squalene, 4.8-10 parts of fatty acids, 40-60 parts of emulsifiers, 20-30 parts of wax esters, 1.6-5 parts of cholesterol, 1-5 parts of antioxidants, 500-1000 parts of water, and a pH regulator that makes the pH value of the simulated skin range from 4.5 to 6.5; The surface friction coefficient of the simulated skin is in the range of 0.4 to 0.6, and the pH value is in the range of 4.5 to 6.5; The base layer is a spunlace nonwoven fabric, and the elastic layer is a polyurethane resin layer; In parts by weight, the elastic layer comprises: 85 to 115 parts of polyurethane resin, 15 to 35 parts of wood powder, 50 to 80 parts of dimethylformamide, and 15 to 35 parts of color powder.

2. The artificial skin for sensory evaluation according to claim 1, characterized in that: The triglyceride is at least one of caprylic / capric triglyceride, glyceryl tripelargonate, and glyceryl trioleate; the wax ester is at least one of jojoba oil, palm wax, candelilla wax, and beeswax; the fatty acid is at least one of palmitic acid, lauric acid, and myristic acid; the antioxidant is at least one of tocopheryl acetate, di-tert-butylparacresol, and tert-butylhydroxyanisole; the emulsifier is at least one of coconut glucoside, cetearyl glucoside, and arachidyl glucoside; and the pH regulator is lactic acid.

3. The method for preparing the artificial skin for sensory evaluation according to any one of claims 1 to 2, characterized in that: Contains the step of applying grease on the surface of the substrate; the preparation method includes the following step: Step 1, preparing a substrate; Step 2, coloring the base body to simulate human skin color; Step 3, embossing the colored substrate with a texture imitating human pores; Step 4, washing and drying the colored and embossed substrate to obtain a substrate simulating the skin color and pore texture of human skin; Step 5, detecting whether the friction coefficient of the substrate surface obtained in step 4 is within the target friction coefficient range, and when the measured friction coefficient is within the target friction coefficient range, proceeding to step 6; otherwise, changing the depth of the human pore-simulating texture on the pattern roller to re-emboss the substrate until the friction coefficient of the substrate surface meets the target friction coefficient range, and proceeding to step 6; Step six, applying a lipid surface layer on the surface of the elastic layer of the substrate whose friction coefficient meets the target friction coefficient range requirements to obtain a finished simulated skin.

4. The method for preparing the artificial skin for sensory evaluation according to claim 3, characterized in that: In the step 1, the step of preparing the substrate includes: The pre-formulated polyurethane resin slurry is evenly coated on the base layer, and the slurry is thinned by an extrusion roller; the slurry is evenly solidified on the base layer through a water solidification tank to obtain an unmodified polyurethane artificial leather; in the step five, the target friction coefficient is in the range of 0.4 to 0.6.

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