Method for constructing moisture sensitivity distribution map under the interaction between clothing and skin

Abstract

The present invention relates to a method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin, and takes into account the influence of clothing design factors and environmental conditions on skin moisture sensitivity. The method comprises the following steps: (1) testing the local skin temperature and humidity, sweat rate, and subjective heat and moisture sensation of a human body during active sweating during exercise under cold and hot environmental conditions, thereby laying the foundation for establishing a skin moisture sensitivity distribution map; (2) constructing a distribution map of local moisture sensitivity of human skin under two environmental conditions and four clothing levels; and (3) analyzing the influence of environmental conditions and clothing design factors on human skin moisture sensitivity. The present invention can provide a theoretical basis for thermal physiological modeling of human skin and is suitable for guiding the thermal and moisture comfort design of sportswear, medical and health care, and functional clothing.

Description

Technical Field

[0001] The present invention relates to a method for constructing a local distribution characteristic map of moisture sensitivity caused by sweating on human skin. The method takes into account the influence of clothing and environmental factors on the distribution characteristic, and belongs to the technical field of thermal and moisture comfort of clothing. The present invention is a project funded by the Shanghai Science and Technology Plan (22ZR1403100). Background Art

[0002] In daily life, high-intensity exercise or exposure to hot environments can lead to profuse sweating. This perspiration can penetrate clothing and even run down the skin, causing intense discomfort (e.g., dampness, stickiness, and stuffiness), impacting the wearing experience. Sensing changes in environmental and skin humidity is crucial for the body's autonomous physiological and behavioral regulation. However, the skin, the body's largest sensory organ, lacks dedicated moisture receptors and instead "learns" to sense wetness through a multi-channel sensory integration. When the skin sweats or comes into contact with a wet object, cold receptors respond due to evaporation of sweat or heat exchange with the contacted object. Mechanoreceptors respond due to the movement of sweat across the skin surface, pressure and adhesion exerted by the contacted object, and acquired perceptual learning allow the brain to synthesize and generate a sense of wetness. Therefore, studying the mechanism and distribution characteristics of human skin moisture sensitivity is a fundamental issue in the field of thermal and moisture comfort in clothing.

[0003] Local thermophysiological differences in human skin are a hot topic of widespread interest among researchers both domestically and internationally. These studies, such as those examining the distribution of skin temperature and sweat rate throughout the human body, have demonstrated the non-uniform physiological distribution of the human skin surface. However, due to the complex mechanisms underlying moisture perception, it remains unclear whether local differences exist across different body segments, and how these distribution characteristics share similarities and differences with the local distribution of skin warmth and coldness. Addressing these issues will not only supplement basic data on human skin physiology but also have practical applications in the design of local comfort for functional clothing and in human neuropsychological simulation. International researchers have studied the distribution of moisture perception from two perspectives. Filingeri's team used thermal probes to apply cold and dry stimulation to different regions of the body, exploring local differences in the skin's sensitivity to moisture. While this approach can convey valuable information, it does not fully represent real-life situations. For example, sweat is produced at varying rates throughout the body, and even then, moisture can be perceived as a sensation on the skin. Compared to passive contact with cold, dry surfaces, the moisture perception of the human-clothing system during active perspiration is equally worthy of investigation. Lee's team used quantified skin wetness as an indicator of thermal strain, evaluating the differences in local skin moisture when wearing breathable and non-breathable clothing in warm environments. However, the distribution of moisture sensitivity across localized areas of the skin surface in both cold and hot environments, taking into account the interaction between clothing fit and breathability, remains to be studied. Summary of the Invention

[0004] The purpose of the present invention is to establish a moisture sensitivity distribution map of ten skin areas of the human body in cold and hot environments, which is suitable for evaluating the impact of clothing design elements on the overall and local moisture sensitivity of the skin when the human body wears clothing for exercise under different environmental conditions.

[0005] In order to achieve the above-mentioned object, the technical solution of the present invention is to provide a method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin, characterized by comprising the following steps:

[0006] Step 1: Conduct a clothing exercise experiment on the subject under cold and hot environment conditions, specifically including the following steps:

[0007] Step 101: According to the body shape of the subject, different types of experimental clothing are made using low-breathable fabrics and high-breathable fabrics, including tight-fitting breathable experimental clothing, tight-fitting non-breathable experimental clothing, loose-fitting breathable experimental clothing, and loose-fitting non-breathable experimental clothing;

[0008] Step 102: fixing temperature and humidity sensors on N different body segments of the subject's skin surface to measure the local skin temperature of each body segment and calculating the local skin humidity of each body segment based on the local skin temperature;

[0009] Step 103: The subject wears different types of experimental clothing and repeats the same exercise in a cold environment and a hot environment, with each exercise lasting a fixed length of time.

[0010] During each exercise session, at fixed intervals, the subjects pointed out the body segments that felt wet and rated the local heat sensation, wetness sensation, and overall comfort of each segment, thereby obtaining subjective experimental data on active sweating during exercise. Simultaneously, temperature and humidity sensors were used to collect and calculate the local skin temperature and humidity of each segment, the average skin temperature of the entire body, and the average skin humidity of the entire body, thereby obtaining objective experimental data on active sweating during exercise.

[0011] Step 2: Analyze the subjective and objective experimental data obtained in step 1 to:

[0012] 1) Obtain the average skin temperature changes of different experimental clothing levels under cold and hot environmental conditions, and then draw the following conclusions:

[0013] Under hot conditions, reducing the breathability of fabrics significantly increased the average skin temperature of exercising people, while the fit of clothing had no significant effect on the average skin temperature.

[0014] In cold conditions, changing the fit of clothing can significantly affect average skin temperature. Loose clothing provides an air layer between the skin and the clothing, increasing the thermal and moisture resistance of the clothing, resulting in a higher skin temperature than close-fitting clothing.

[0015] 2) Obtain the average skin moisture changes under cold and hot environmental conditions for different types of experimental clothing, and then draw the following conclusions:

[0016] In hot conditions, wearing loose breathable clothing can significantly reduce the accumulation of sweat on the human skin surface and reduce the humidity under the clothes during exercise;

[0017] In cold conditions, inhibiting the breathability of clothing will significantly increase the average skin humidity, while clothing looseness has no significant effect on skin humidity;

[0018] 3) Constructing a distribution map of local moisture sensitivity of human skin

[0019] The percentage of wet sensation in each body segment is defined as the evaluation index of the local wet sensitivity of the current body segment. The percentage of wet sensation in the current body segment is the number of times that the current body segment was perceived as wet by all subjects during the entire wearing and exercise experiment divided by the total number of evaluations. The higher the percentage of wet sensation in a body segment, the higher the local wet sensitivity of the current body segment.

[0020] Based on the percentage of wet sensation, local wet sensitivity is divided into different levels, and then multi-level distribution maps of human wet sensitivity under hot and cold environment conditions are constructed respectively. Based on the multi-level distribution map analysis, the local wet sensitivity differences of different body segments under hot and cold environment conditions and different types of experimental clothing wearing conditions are obtained;

[0021] Step 3: Analyze the impact of environmental conditions and clothing design on human skin moisture sensitivity, and establish a mathematical model to predict subjective moisture sensitivity based on skin physical moisture, where:

[0022] When establishing a mathematical model for predicting subjective moisture sensitivity based on skin physical moisture, the local skin moisture of different body segments was used as the independent variable and the percentage of moisture sensation was used as the dependent variable under hot and cold environmental conditions. Scatter plots were drawn, and after data fitting, a functional relationship between local skin moisture and the percentage of moisture sensation under hot environmental conditions and a functional relationship between local skin moisture and the percentage of moisture sensation under cold environmental conditions were established, thus completing the mathematical model.

[0023] By analyzing the influence of clothing design factors on moisture sensitivity, the following conclusions were obtained:

[0024] In hot environments, you should wear loose and breathable sportswear to promote the evaporation of sweat, reduce skin moisture and thus reduce the body's discomfort caused by moisture; in cold environments, you should wear tight and breathable clothing to reduce intermittent contact and stickiness between the skin and clothing, thereby reducing the body's discomfort caused by moisture.

[0025] Preferably, in step 101, the low-air-permeability fabric and the high-air-permeability fabric are obtained based on the same elastic knitted fabric.

[0026] Preferably, the experimental clothing is in the form of a one-piece suit, with cuffs and trouser legs closed with pure cotton ribbed fabric, and a collar that fits the human neck.

[0027] Preferably, an artificial climate chamber with controllable temperature and humidity is used to simulate the cold environment and the hot environment.

[0028] Preferably, the average skin temperature of the whole body is calculated using the eight-point method As shown in formula (1):

[0029]

[0030] In formula (1), T 前额 、T 右上臂 、T 左小臂 、T 右肩胛 、T 左前胸 、T 右前大腿 、T 左小腿 、T 左手背 They respectively represent the temperature values of the corresponding body segments collected by the temperature and humidity sensors.

[0031] Preferably, the local skin moisture value is calculated using the following formulas (2) to (4):

[0032]

[0033]

[0034]

[0035] In formula (2) to formula (4), w local is the local skin moisture, no unit; P sk,s is the saturated water vapor pressure on the skin surface, in Pa; P a is the water vapor pressure in the environment, in Pa; P sk is the water vapor pressure on the skin surface, in Pa; RH is the relative humidity, which is the humidity measurement value of the corresponding body segment, in %; T sk is the temperature measurement value of the corresponding body segment, in °C;

[0036] In formula (1), T 前额 、T 右上臂 、T 左小臂 、T 右肩胛 、T 左前胸 、T 右前大腿 、T 左小腿 、T 左手背 The local skin humidity values w of the forehead, right upper arm, left forearm, right shoulder blade, left chest, right front thigh, left calf and left arm calculated by equations (2) to (4) are respectively local Replace , then according to the modified formula (1) we can get the average skin humidity of the whole body.

[0037] Preferably, the percentage of wet sensation in each body segment is used as the basis for dividing the local wet sensitivity, and the local wet sensitivity is divided into 5 levels: Level 5 is the percentage of wet sensation exceeding 70%, Level 4 is the percentage of wet sensation between 50-70%, Level 3 is the percentage of wet sensation between 30-50%, Level 2 is the percentage of wet sensation between 10-30%, and Level 1 is the percentage of wet sensation below 10%.

[0038] This paper proposes a method for measuring the local distribution characteristics of human skin moisture sensitivity under the interaction of clothing fit and breathability in cold environments (15°C) and hot environments (30°C). This method aims to guide the design of thermal and moisture comfort for sportswear, medical and health care, and functional clothing. This method analyzes the characteristics of skin moisture sensitivity under the combined influence of environmental conditions and clothing design factors, establishing a moisture sensitivity distribution map for human skin. This method provides a basis for the zoning design of functional sportswear and the optimization of clothing performance to meet skin moisture comfort requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is the experimental flow chart of the present invention;

[0040] Figure 2 This is a schematic diagram of the human body segment divisions in the present invention, in which 1-forehead 2-upper arm 3-forearm 4-front chest 5-abdomen 6-thigh 7-calf 8-upper back 9-lower back 10-buttocks;

[0041] Figure 3 is a schematic diagram of the distribution of skin moisture sensitivity in a thermal environment of the present invention;

[0042] Figure 4 is a schematic diagram of the distribution of skin moisture sensitivity in a cold environment according to the present invention;

[0043] Figure 5 The finished product of the experimental garment in the embodiment is shown;

[0044] Figure 6(a) to Figure 6(c)The subjective evaluation scales are shown, where FIG6(a) shows the wetness rating scale, FIG6(b) shows the thermal sensation rating scale, and FIG6(c) shows the comfort rating scale;

[0045] Figure 7 The average skin temperature changes in a thermal environment are shown;

[0046] Figure 8 The average skin temperature changes in cold environment are shown;

[0047] Figure 9 The average skin humidity changes in a thermal environment are shown;

[0048] Figure 10 The average skin moisture changes in cold environment are shown;

[0049] Figures 11(a) and 11(b) illustrate the relationship between the percentage of wet sensation and physical skin humidity. Figure 11(a) is a hot environment, and Figure 11(b) is a cold environment. In the figures, the subjective wet sensation perception rate is the percentage of wet sensation. DETAILED DESCRIPTION

[0050] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0051] The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin disclosed in this embodiment specifically includes the following steps:

[0052] Step 1: Conduct a clothing-based exercise experiment with subjects in both cold and hot environments. This human exercise experiment measures local skin temperature and humidity, sweat rate, subjective moisture sensation, and comfort while actively sweating while wearing the experimental clothing. This provides a data foundation for establishing a moisture-sensitive local distribution map.

[0053] In this embodiment, the experimental plan for the clothing exercise experiment includes: 1) designing and producing four experimental garments with different fits and breathabilities; 2) simulating low and high temperature working conditions in an artificial climate chamber with controllable temperature and humidity. When the subjects wear the four experimental garments and exercise on a treadmill, the subjective and objective physiological and psychological reactions of 10 body segments and the whole body are tested.

[0054] Experimental clothing: The same elastic knitted fabric (85% polyester, 15% spandex) was used to prepare the experimental clothing. One of the fabrics was coated with a PU film on the outer surface to inhibit breathability, while the other was not coated to maintain high breathability. The experimental fabric parameters are shown in Table 1, where the fabric with a PU film on the outer surface is represented by code F, and the fabric without a PU film is represented by code WF.

[0055] Table 1 Experimental fabric parameters

[0056]

[0057] Two kinds of fabrics were used to design close-fitting clothing (codenamed T) that was one size smaller than the standard body size (female: 160 / 84A; male: 175 / 92A) and loose clothing (codenamed L) that was two sizes larger for male and female subjects respectively. In order not to affect the test of the buttocks, in this embodiment, the clothing style adopted was a jumpsuit, and the cuffs and trouser legs were closed with pure cotton rib fabric, and the collar also fit the human neck. Therefore, four types of experimental clothing were finally obtained, namely tight-fitting and breathable (TWF) type experimental clothing, tight-fitting and non-breathable (TF) type experimental clothing, loose-fitting and breathable (LWF) type experimental clothing, and loose-fitting and non-breathable (LF) type experimental clothing, a total of four types of experimental clothing, constituting different clothing design elements. The specific size specifications of the experimental clothing are shown in Table 2, and the finished product display takes women's clothing as an example, as shown in Table 2. Figure 5 As shown, Figure 5 From left to right in the middle are TWF type experimental clothing, TF type experimental clothing, LWF type experimental clothing and LF type experimental clothing.

[0058] Table 2 Clothing specifications and dimensions Unit: cm

[0059]

[0060] Environmental Conditions: Experiments were conducted in a temperature- and humidity-controlled artificial climate chamber. Low-temperature conditions: 15°C, 87% relative humidity; high-temperature conditions: 30°C, 35% relative humidity. In both environments, wind speeds were less than 0.3 m / s, and the water vapor partial pressure was 1482 Pa.

[0061] Experimental Procedure: Twelve subjects were recruited, including six male and six female subjects. Subjects were required to exercise regularly, participating in at least two sessions per week, with each session lasting at least one hour. Each subject was required to wear four different types of clothing for the experiment, both in hot and cold environments. The two experiments were conducted at least 48 hours apart, and the experiments for the same subject were scheduled at the same time on different days. The order of the clothing was randomized. Female subjects were required to avoid wearing the clothing during their menstrual period.

[0062] The experimental process is as follows Figure 1As shown, the subjects first balanced in the environmental chamber for 30 minutes, during which time the experimenter familiarized themselves with the evaluation scale and trained them on how to use it. After the balance was completed, the experimenter weighed the weight of the experimental clothing, towels, shoes and socks, and drinking water. After the weighing was completed, the subjects were assisted to wear the heart rate monitor (Polar Electro, Finland) correctly, and the naked weight of the subjects was recorded. Ten temperature and humidity sensors (Ibuttons, USA) were attached to 10 designated locations on the skin surface using medical tape to measure the local skin temperature (Tsk) and calculate the local skin humidity (W local ). The subjects then randomly selected a piece of experimental clothing to wear, and evaluated the thermal sensation, wetness and comfort of the whole body and 10 body segments at the 15th minute. The subjects then put on the experimental clothing and conducted a 50-minute formal experiment: the subjects first warmed up on a treadmill (h / p / cosmos, Germany) for 10 minutes, and then exercised on the treadmill at a walking speed of 5Km / h for 40 minutes, increasing the slope by 2% every 5 minutes until it reached a slope of 14%. During the experiment: the ear canal temperature of the subjects was collected every 5 minutes using an ear thermometer, and the subjects were asked to compare the temperature with the 10 body segment division diagram of the human body (such as Figure 2 (as shown), participants were asked to indicate the body segments that felt wet and to rate their local heat sensation, wetness sensation, and overall comfort in each segment. (The experimenter asked participants whether they felt wet in each of ten body segments (in a random order). If they answered "yes," they were further evaluated for the intensity of the local wet sensation, as well as their overall heat, wetness sensation, and comfort.) Physiological data, including skin temperature, relative humidity of the air beneath the clothing, and heart rate, were collected every minute. After the experiment, participants removed their lab coats and the clothing and naked weight were immediately measured.

[0063] Each subject was required to complete eight running tests, with at least 24 hours between each. Each experiment involved measuring the subjective, objective, and psychological responses of ten body segments (forehead, upper arm, forearm, chest, abdomen, thigh, calf, upper back, lower back, and buttocks) and the entire body while wearing four experimental garments under a single environmental condition (high or low temperature).

[0064] In the aforementioned clothing sports experiment, subjective evaluations of local wetness sensation and overall heat, wetness, and comfort sensation were conducted, and subjective experimental data were obtained. In this embodiment, the evaluation method and specific scoring scales used are as follows: Figure 6(a) to Figure 6(c) shown.

[0065] In the aforementioned dressed exercise experiment, the average skin temperature and skin humidity are further calculated based on the temperature data and humidity data collected by the temperature and humidity sensors arranged at 10 body segments of the human body.

[0066] The calculation of average skin temperature includes:

[0067] Calculate the average skin temperature using the eight-point method according to standard ISO 9886:2004 As shown in Formula 1:

[0068]

[0069] In formula (1), T 前额 、T 右上臂 、T 左小臂 、T 右肩胛 、T 左前胸 、T 右前大腿 、T 左小腿 、T 左手背 They respectively represent the temperature values of the corresponding body segments collected by the temperature and humidity sensors.

[0070] The calculation of skin moisture includes:

[0071] Based on the relative humidity values under the clothes collected by the temperature and humidity sensors, the local and average skin humidity values are calculated. The local skin humidity values are calculated using the following equations (2) to (4):

[0072]

[0073]

[0074]

[0075] In formula (2) to formula (4), w local is the local skin moisture, no unit; P sk,s is the saturated water vapor pressure on the skin surface, in Pa; P a is the water vapor pressure in the environment, in Pa; P sk is the water vapor pressure on the skin surface, in Pa; RH is the relative humidity, collected by the humidity sensor, in %; T sk is the temperature measurement value of the corresponding body segment, in °C.

[0076] In formula (1), T 前额 、T 右上臂 、T 左小臂 、T 右肩胛 、T 左前胸 、T 右前大腿 、T 左小腿 、T 左手背 The local skin humidity values w of the forehead, right upper arm, left forearm, right shoulder blade, left chest, right front thigh, left calf and left arm calculated by equations (2) to (4) are respectively localReplace , then according to the modified formula (1) we can get the average skin humidity of the whole body.

[0077] Step 2: Analyze the subjective and objective experimental data, and construct two environmental conditions of cold and hot and four experimental clothing levels:

[0078] 1) Changes in average skin temperature in cold and hot environments

[0079] The average skin temperature during the experiment was significantly higher in the hot environment (33.21±0.59)℃ than in the cold environment (25.64±0.82)℃ [F(1,11)=3008.923, p<0.001]. Figure 7 As shown, the initial values for the four types of experimental clothing were between 32.5 and 32.6°C, with no significant differences [F(3, 33) = 1.54, p = 0.22]. After the start of exercise, the non-breathable clothing showed a linear increase over time, ultimately reaching 34°C, higher than the breathable clothing. Clothing type [F(3, 33) = 25.32, p < 0.001] had a significant effect on average skin temperature. The average skin temperature of non-breathable clothing was significantly higher than that of breathable clothing (p < 0.05), but there was no significant difference between close-fitting and loose-fitting clothing (p > 0.05), indicating that reducing the breathability of the fabric significantly increased the average skin temperature of the exercising body, while the fit of the clothing had no significant effect on average skin temperature.

[0080] The average skin temperature of the four types of experimental clothing in a cold environment is as follows Figure 8 As shown, there was no difference in skin temperature between the four types of experimental clothing during the P1 rest phase. During the P2 exercise phase, both loose-fitting clothing had higher skin temperatures than close-fitting clothing, with the LF type having the highest temperature and the TWF type having the lowest temperature. Clothing type [F(3,33)=24.04, p<0.001] had a significant effect on average skin temperature. The average skin temperature of the LF type experimental clothing was significantly higher than that of the other three types of experimental clothing (p<0.05), and the LWF type experimental clothing was significantly higher than the TWF type experimental clothing (p=0.02). There was no significant difference between the TF type experimental clothing and the TWF and LWF types of experimental clothing (p>0.05). This indicates that changing the fit of clothing can significantly affect average skin temperature. Loose-fitting clothing provides an air layer between the human skin and the clothing, increasing the thermal and moisture resistance of the clothing, resulting in higher skin temperature compared to close-fitting clothing.

[0081] 2) Changes in average skin moisture in cold and hot environments

[0082] The average skin humidity in hot environment (0.872±0.12) was significantly higher than that in cold environment (0.576±0.23) by 0.296 (p<0.001), and the average skin humidity of each type of experimental clothing in hot environment was higher than that in cold environment. Figure 9 The type of clothing had a significant effect on average skin humidity [F(3,33)=12.174, p<0.001]. The average skin humidity under the LWF type experimental clothing was significantly lower than that under the other types of experimental clothing (p<0.05), while there was no significant difference between the other types of experimental clothing (p>0.05). This shows that wearing loose and breathable clothing can significantly reduce the accumulation of sweat on the human skin surface and reduce the humidity under the clothing during exercise.

[0083] The average skin humidity changes over time when wearing four types of experimental clothing in a cold environment are as follows Figure 10 As shown. Clothing type had a significant effect on average skin moisture [F(3,33)=14.798, p<0.001]. Average skin moisture was highest under the TF-type experimental garment, significantly higher by 0.103% than the TWF-type experimental garment (p=0.002) and by 0.113% than the LWF-type experimental garment (p<0.001), but not significantly different from the LF-type experimental garment (p=0.267). Average skin moisture was lowest under the LWF-type experimental garment, but not significantly different from the TWF-type experimental garment (p=1.000). This indicates that inhibiting the breathability of clothing significantly increases average skin moisture, while clothing looseness has no significant effect on skin moisture.

[0084] 3) Distribution of local moisture sensitivity of human skin

[0085] An evaluation index for wet sensitivity is established, with the percentage of subjects perceiving local wetness, i.e., the percentage of wet sensation occurring at each position, as a basis for the division of local wet sensitivity. The percentage of wet sensation occurring at a certain position is the number of times that the current position of the human body is perceived as wet by all subjects during the entire dressing exercise experiment, divided by the total number of evaluations. The higher the percentage of wet sensation occurring, the higher the local wet sensitivity of the position. In the present embodiment, under the dressing conditions of each type of experimental clothing, there are 12 subjects, and each test position is evaluated 11 times, so the total number of evaluations at each position is 132 times. The number of times that each position is perceived as wet during the entire test process, divided by the total number of evaluations (132 times), is counted to obtain the percentage of wet sensation occurring at the position, which is used as a basis for the division of local wet sensitivity. The present invention uses the percentage of wet sensation in each part as the basis for dividing local wet sensitivity, and divides the wet sensitivity into five levels: Level 5 is the percentage of wet sensation exceeding 70%, Level 4 is the percentage of wet sensation between 50-70%, Level 3 is the percentage of wet sensation between 30-50%, Level 2 is the percentage of wet sensation between 10-30%, and Level 1 is the percentage of wet sensation below 10%.

[0086] Figure 3 The figure shows the five-level distribution of human moisture sensitivity in a thermal environment. The forehead has the highest moisture sensitivity, at level 5, under all four types of experimental clothing. The chest and lower back are at level 4 under all four types of experimental clothing. The upper back is at level 5 under the TF type experimental clothing and at level 4 under the other types of experimental clothing. The thigh, abdomen, and forearm are at level 4 under the LF type experimental clothing and at level 3 under the other three types of experimental clothing. The calf is at level 3 under the LF type experimental clothing and at level 2 under the other three types of experimental clothing. The buttocks are at level 3 under all four types of experimental clothing. The upper arm is at level 4 under the LF and TWF types of experimental clothing and at level 3 under the TF and LWF types of experimental clothing. The moisture sensitivity ranking under the four types of experimental clothing is: LF > TF > TWF > LWF. There was no significant difference between different parts of the body at the same moisture sensitivity level (p>0.05). When comparing the moisture sensitivity of the four types of experimental clothing, it was found that the moisture sensitivity of the thighs and calves when wearing LF type experimental clothing was significantly higher than that of the other three types of experimental clothing (p<0.05). It is speculated that running increases the mechanical friction between loose clothing and leg skin, resulting in enhanced moisture perception.

[0087] Figure 4The figure shows the distribution of human moisture sensitivity in cold environments. Compared with hot environments, moisture sensitivity in cold environments is the highest at level 3. The frequency of moisture perception in individual garments on the buttocks, thighs, and calves does not exceed 10%. The forehead is at level 3 for all four types of experimental clothing. The upper back is at level 2 for the TWF type experimental clothing and at level 3 for the other three types. The chest is at level 3 for the LF type experimental clothing and at level 2 for the other three types. The upper arms, forearms, front abdomen, and lower back are all at level 2. The buttocks are at level 1 for the TWF type experimental clothing and at level 2 for the other three types. The thighs are at level 2 for the non-breathable garments and at level 1 for the breathable garments. The calves are at level 2 for the LF type experimental clothing and at level 1 for the other three types. The moisture sensitivity ranking for the four types of experimental clothing was: LF > TF > LWF > TWF. There were no significant differences between the various parts of the body within the same moisture sensitivity level (p>0.05). Comparing the moisture sensitivity of the four types of experimental clothing, it was found that in the upper arm, the frequency of perceived moisture was significantly lower in the TWF experimental clothing than in the TF experimental clothing (p<0.05). The frequency of perceived moisture in the thigh and calf was significantly lower in the LWF experimental clothing than in the LF experimental clothing (p<0.05). Similar to the hot environment, non-breathable clothing significantly increased moisture sensitivity, but in the cold environment, clothing fit had no significant effect on moisture sensitivity.

[0088] Although the moisture sensitivity levels of different parts of the body in cold and hot environments are different, the division of local moisture sensitivity remains consistent, that is, the forehead has the highest moisture sensitivity, followed by the upper back, chest and lower back, third are the upper arms, forearms, front abdomen and buttocks, and finally the thighs and calves.

[0089] Step 3: Analyze the impact of environmental conditions and clothing design on human skin moisture sensitivity, and establish a mathematical model to predict subjective moisture sensitivity based on skin physical moisture. This specifically includes the following steps:

[0090] 1) Impact of environmental conditions on moisture sensitivity

[0091] Using the physical skin humidity of 10 body segments as the independent variable and the percentage of wet sensation as the dependent variable, a scatter plot was plotted and a linear regression equation was applied to the data. The fitting results are shown in Figure 11. As can be seen from the figure, the slope of the fitted line for the hot environment is greater than that for the cold environment, indicating that human skin is more sensitive to moisture in hot environments than in cold environments (the slope is approximately 2.7 times that of the cold environment). This is because people sweat more easily in hot environments, and skin humidity is significantly higher in cold environments. However, at the same skin humidity, the sensitivity to moisture perception in cold environments is higher than in hot environments. For example, at a skin humidity of 0.8, the frequency of wet sensation in hot environments is 32%, while the frequency of wet sensation in cold environments is 50%. Therefore, under the same skin sweating amount, the human body is more sensitive to wet sensation in cold environments, which is commonly referred to as a more intense wet-cold sensation. The frequency of subjective wet sensation in hot and cold environments can be predicted using the following equation:

[0092] Thermal environment: y = 318.63x - 222.98

[0093] Cold environment: y = 117.86x - 43.87

[0094] Wherein, y is the percentage (%) of wet sensation, and x is the physical skin wetness (unitless).

[0095] 2) Impact of clothing design factors on moisture sensitivity

[0096] The overall moisture sensitivity of garments in hot environments ranked from high to low as LF > TF > TWF > LWF, while in cold environments it ranked from high to low as LF > TF > LWF > TWF. This indicates that, regardless of the environment, garments coated with a vapor-impermeable film (F) exhibited higher moisture sensitivity than uncoated, breathable garments (WF). Suppressing evaporative vapor permeability in garments is detrimental to reducing the sense of moisture. Furthermore, loose-fitting garments were more susceptible to moisture sensation than close-fitting garments (LF > TF). This suggests that loose-fitting garments increase intermittent adhesion to (wet) skin, stimulating mechanoreceptor responses and thus enhancing the skin's ability to sense moisture. Under uncoated conditions, close-fitting garments exhibited higher moisture sensitivity in hot environments than loose-fitting garments (TWF > LWF). This is primarily due to the significantly lower skin humidity in hot environments associated with loose-fitting, breathable garments, resulting in the lowest subjective moisture sensitivity. In cold environments, loose-fitting clothing has a higher moisture sensitivity than close-fitting clothing (LWF>TWF). This is because there is no significant difference in skin moisture between loose and close-fitting clothing in cold environments. Loose-fitting clothing, however, provides more frequent mechanical input to the skin during exercise, increasing moisture sensitivity. Therefore, in hot environments, loose, breathable sportswear should be worn to promote sweat evaporation, reduce skin moisture, and thus reduce moisture discomfort. In cold environments, tight, breathable clothing should be worn to reduce intermittent contact and adhesion between skin and clothing, thereby reducing moisture discomfort.

Claims

1. A method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin, characterized in that: The following steps are involved: Step 1: Conduct a clothing exercise experiment on the subject under cold and hot environment conditions, specifically including the following steps: Step 101: according to the body shape of the subject, different types of experimental clothing are made using low-breathable fabrics and high-breathable fabrics, including tight-fitting breathable experimental clothing, tight-fitting non-breathable experimental clothing, loose-fitting breathable experimental clothing, and loose-fitting non-breathable experimental clothing; Step 102: fixing temperature and humidity sensors on N different body segments of the subject's skin surface to measure the local skin temperature of each body segment and calculate the local skin humidity of each body segment based on the local skin temperature; Step 103: The subject wears different types of experimental clothing and repeats the same exercise in a cold environment and a hot environment, with each exercise lasting a fixed length of time. During each exercise session, at fixed intervals, the subjects pointed out the body segments that felt wet and rated the local heat sensation, wetness sensation, and overall comfort of each segment, thereby obtaining subjective experimental data on active sweating during exercise. Simultaneously, temperature and humidity sensors were used to collect and calculate the local skin temperature and humidity of each segment, the average skin temperature of the entire body, and the average skin humidity of the entire body, thereby obtaining objective experimental data on active sweating during exercise. Step 2: Analyze the subjective and objective experimental data obtained in step 1 to: 1) Obtain the average skin temperature changes of different experimental clothing levels under cold and hot environmental conditions, and then draw the following conclusions: Under hot conditions, reducing the breathability of fabrics significantly increased the average skin temperature of exercising people, while the fit of clothing had no significant effect on the average skin temperature. In cold conditions, changing the fit of clothing can significantly affect average skin temperature. Loose clothing provides an air layer between the skin and the clothing, increasing the thermal and moisture resistance of the clothing, resulting in a higher skin temperature than close-fitting clothing. 2) Obtain the average skin moisture changes under cold and hot environmental conditions for different types of experimental clothing, and then draw the following conclusions: In hot conditions, wearing loose breathable clothing can significantly reduce the accumulation of sweat on the human skin surface and reduce the humidity under the clothes during exercise; In cold conditions, inhibiting the breathability of clothing will significantly increase the average skin humidity, while clothing looseness has no significant effect on skin humidity; 3) Constructing a distribution map of local moisture sensitivity of human skin The percentage of wet sensation in each body segment is defined as the evaluation index of the local wet sensitivity of the current body segment. The percentage of wet sensation in the current body segment is the number of times that the current body segment was perceived as wet by all subjects during the entire wearing and exercise experiment divided by the total number of evaluations. The higher the percentage of wet sensation in a body segment, the higher the local wet sensitivity of the current body segment. Based on the percentage of wet sensation, local wet sensitivity is divided into different levels, and then multi-level distribution maps of human wet sensitivity under hot and cold environment conditions are constructed respectively. Based on the multi-level distribution map analysis, the local wet sensitivity differences of different body segments under hot and cold environment conditions and different types of experimental clothing wearing conditions are obtained; Step 3: Analyze the impact of environmental conditions and clothing design on human skin moisture sensitivity, and establish a mathematical model to predict subjective moisture sensitivity based on skin physical moisture, where: When establishing a mathematical model for predicting subjective moisture sensitivity based on skin physical moisture, the local skin moisture of different body segments was used as the independent variable and the percentage of moisture sensation was used as the dependent variable under hot and cold environmental conditions. Scatter plots were drawn, and after data fitting, a functional relationship between local skin moisture and the percentage of moisture sensation under hot environmental conditions and a functional relationship between local skin moisture and the percentage of moisture sensation under cold environmental conditions were established, thus completing the mathematical model. By analyzing the influence of clothing design factors on moisture sensitivity, the following conclusions were obtained: In hot environments, you should wear loose and breathable sportswear to promote the evaporation of sweat, reduce skin moisture and thus reduce the body's discomfort caused by moisture; in cold environments, you should wear tight and breathable clothing to reduce intermittent contact and stickiness between the skin and clothing, thereby reducing the body's discomfort caused by moisture.

2. The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin according to claim 1, characterized in that: In step 101, the low-air-permeability fabric and the high-air-permeability fabric are obtained based on the same elastic knitted fabric.

3. The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin according to claim 1, characterized in that: The experimental clothing is a one-piece suit, with cuffs and trouser legs closed with pure cotton rib fabric, and the collar also fits the human neck.

4. The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin according to claim 1, characterized in that: The cold environment and the hot environment are simulated by using an artificial climate chamber with controllable temperature and humidity.

5. The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin according to claim 1, characterized in that: Calculate the average skin temperature of the whole body using the eight-point method As shown in formula (1): In formula (1), T 前额 、T 右上臂 、T 左小臂 、T 右肩胛 、T 左前胸 、T 右前大腿 、T 左小腿 、T 左手背 They respectively represent the temperature values of the corresponding body segments collected by the temperature and humidity sensors.

6. The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin according to claim 5, characterized in that: The local skin humidity value is calculated using the following formulas (2) to (4): In formula (2) to formula (4), w local is the local skin moisture, no unit; P sk,s is the saturated water vapor pressure on the skin surface, in Pa; P a is the water vapor pressure in the environment, in Pa; P sk is the water vapor pressure on the skin surface, in Pa; RH is the relative humidity, which is the humidity measurement value of the corresponding body segment, in %; T sk is the temperature measurement value of the corresponding body segment, in °C; In formula (1), T 前额 、T 右上臂 、T 左小臂 、T 右肩胛 、T 左前胸 、T 右前大腿 、T 左小腿 、T 左手背 The local skin humidity values w of the forehead, right upper arm, left forearm, right shoulder blade, left chest, right front thigh, left calf and left arm calculated by equations (2) to (4) are respectively local Replace , then according to the modified formula (1) we can get the average skin humidity of the whole body.

7. The method for constructing a moisture sensitivity distribution map under the interaction between clothing and skin according to claim 1, characterized in that: The percentage of wet sensation in each body segment is used as the basis for dividing the local wet sensitivity, and the local wet sensitivity is divided into 5 levels: Level 5 is the percentage of wet sensation exceeding 70%, Level 4 is the percentage of wet sensation between 50-70%, Level 3 is the percentage of wet sensation between 30-50%, Level 2 is the percentage of wet sensation between 10-30%, and Level 1 is the percentage of wet sensation below 10%.

Images