Cooling sensation composition and use thereof

Abstract

An object of the present invention is to provide a cool feeling composition having a specific composition which is excellent in durability of cooling function.SOLUTION: The present invention provides a cool feeling composition characterized by blending (a) octadecane and / or (b) polyacrylic acid amide as a phase change material in order to constitute a base of cool feeling characteristics which is an object of the present invention, and two inventions are constituted on the basis of the constitution of the base to exhibit effects. In the first invention, it is intended to provide an optimal single-layer type cooling composition having an adjusted melting point, and in the second invention, it is intended to provide an optimal two layer type cooling composition having an adjusted melting point, which is a cooling sustain-enhancing type.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a cooling composition of a specific composition that exhibits excellent long-lasting cooling properties and its applications. More specifically, the present invention provides a cooling composition that can exhibit excellent cooling properties by incorporating (a) octadecane and / or (b) polyacrylic acid amide as a phase change material (hereinafter referred to as PCM material), and its applications. [Background technology]

[0002] Needless to say, climate change caused by global warming in recent years has led to unexpected disasters and has had a major impact on daily life. Measures to combat the summer heat, which is particularly life-threatening, are an urgent issue that requires national attention.

[0003] In this regard, the Ministry of the Environment issues heatstroke prevention information and heatstroke warning information based on the heat index, which is used to predict hot seasons and tropical nights, and to take measures against the heat environment in urban planning, etc.

[0004] Here, the "heat index" is an index that expresses heat and is generally calculated taking into account temperature and humidity. The heat index is used to objectively evaluate the degree of heat and is useful, for example, for determining the risk of heatstroke and comfort.

[0005] The calculation method and names of heat indices may vary depending on the region or country, but the following indicators are commonly used: (1) Heat Index: A temperature index that takes humidity into account. It was proposed by the American Meteorological Society and expresses the heat felt by the human body through a combination of temperature and relative humidity. (2) Discomfort Index: An index that combines temperature and humidity and is used in some countries, including Japan. It evaluates heat and humidity and indicates the degree of discomfort. (3) Humidity Index (Humidex): This index is mainly used in Canada and is a combination of temperature and relative humidity. It is used to express the feeling of humidity and to determine the risk of heatstroke.

[0006] These heat indices are useful for planning activities in hot environments and preventing heatstroke, so weather information and heatstroke prevention information regularly released by local meteorological and health agencies often provides advice and alert levels based on the heat index.

[0007] However, it is up to each individual to put this information into practice, and their awareness and knowledge are extremely important in personal care. The higher the heat index, the more likely you are to feel hot and the greater the risk of heatstroke, so naturally, preventive measures to lower the heat index are important.

[0008] Generally, the following are preventative measures that individuals can take to lower the heat index: (1) Appropriate clothing: Choose thin, breathable clothing, light-colored clothing, and clothing with UV protection to reduce the glare of sunlight. (2) Adequate fluid intake: Drink plenty of water and sports drinks to prevent dehydration. In hot environments, you need to drink more fluid than usual. (3) Activities in the shade: Avoid direct sunlight and spend as much time in the shade as possible. It is important to stay in the shade of a tree or under a sunshade, or in a cool place. (4) Rest and rest in a cool place: After a long time outdoors or exercise, rest in a cool place. Resting your body will help prevent your body temperature from rising. (5) Use of heatstroke prevention products: Using heatstroke prevention products such as cooling towels and neck coolers can help cool the body. These products can be used by soaking them in water or by cooling them in the refrigerator. (6) Activities at appropriate times: Avoid strong direct sunlight, especially during the day, and be active in the cooler mornings or evenings. (7) Maintaining a cool indoor environment: It is also important to adjust the indoor temperature and maintain a cool environment. It is important to lower the room temperature using an air conditioner or fan.

[0009] By following these preventative measures, you can prevent heatstroke and illness caused by the heat and stay comfortable, but special personal care is needed for those at particular risk of heatstroke, such as the elderly, children, and those in poor health.

[0010] On the other hand, goods that support the aforementioned personal care are also available on the market, and the development and utilization of even more convenient products is also very important in terms of countermeasures. In this regard, products specializing in cooling functions, as mentioned in the above measure (5), are attracting particular attention.

[0011] Conventionally, cooling ingredients have been used, but these lacked long-lasting effectiveness and were not noticeable. For example, Patent Document 1 discloses a cooling cosmetic product that provides a noticeable cooling sensation immediately after application, has excellent durability, and is less irritating. However, the composition of the cooling cosmetic product is a solid cooling composition containing a cooling substance that dissolves in water and causes an endothermic reaction, and the cooling sensation lacks durability, and the cosmetic product is not composed of materials that are particularly focused on preventing heatstroke.

[0012] Therefore, because they are unsuitable as materials for dealing with the high temperatures experienced in the summer, which have become commonplace in recent years, further improvements have been made, and development of cooling sensation compositions that allow the device itself to maintain its functionality, as well as their applications, has been promoted.

[0013] In recent years, particular attention has been focused on phase change materials, or PCM materials. A phase change material (PCM) is a substance that undergoes a phase transition within a specific temperature range, exchanging thermal energy at its melting or freezing point. When a PCM reaches its melting point, it transitions from solid to liquid, and when it reaches its freezing point, it transitions from liquid to solid. During this phase transition, heat is stored or released, giving it the property of stabilizing the surrounding temperature.

[0014] Examples of cooling materials that utilize this property include those disclosed in Patent Documents 2 and 3. Patent Document 2 discloses a technology for a sustained cool temperature regulating yarn and a manufacturing method thereof. According to this technology, the fiber of the invention includes a specific outer skin and a core, the outer skin completely enveloping the core, and the core is made of a PCM or a phase change latent heat wax. The cross-sectional area of ​​the PCM or the phase change latent heat wax accounts for 5-70% of the cross-sectional area of ​​the fiber, allowing a greater amount of the phase change material PCM to be directly injected into the fiber core. These techniques enable textile products to achieve a higher cool sensation value, significantly improving the product's sustained cool sensation and satisfying the user's cooling sensation.

[0015] However, it is not clear how the cooling sensation is manifested in relation to the PCM composition and the control temperature, and what actual effects have been found, making this technology impractical as a tool for preventing heatstroke.

[0016] Patent Document 3 discloses a cushion body with a cooling sensation and high breathability that can be used in mattresses, carpets, mattress pads, pillows, sleeping mats, and even various electrical appliances. It discloses that each of the above products uses a cooling gel on the surface of the cushion, and that the cooling gel contains a phase change material PCM, so that a stable cooling sensation can be maintained at all times.

[0017] However, since the cooling gel layer is present in a continuous layer on the surface, it undergoes a phase transition in a short period of time, and therefore the cooling sensation is not sustained with sufficient stability.

[0018] For these reasons, there is a need for a composition that is particularly effective in providing a long-lasting cooling sensation. As mentioned above, a particularly prioritized use of cooling compositions in personal care is as a commercial product for preventing heatstroke, and one of the devices that has been developed and appeared on the market as being most likely to be effective in preventing heatstroke is the neck cooling device.

[0019] In view of this, the applicant has provided a neck cooling device to quickly meet these market needs. However, while conventional products have the desired cooling power and durability, depending on the freezing point (for example, when adjusted to 28 degrees), they remain in a solidified, hard state, which results in a poor fit around the neck, and improvements were needed. This technique has the same drawbacks when used on bedding such as pillows and mattress pads. Although the desired cool sensation can be achieved, the material feels very hard and stiff, so improvements are needed in terms of the sensation and affinity to the material leading up to falling asleep. [Prior art documents] [Patent documents]

[0020] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-207788 [Patent Document 2] Japanese Patent Application Publication No. 2023-36527 [Patent Document 3] Registered Utility Model No. 3241240 Summary of the Invention [Problem to be solved by the invention]

[0021] The present invention has been made in view of the above-mentioned unsolved problems, and aims to provide a cooling sensation composition composed of a phase-change material that has good affinity with the skin and is essential for exhibiting a stable cooling function, and uses thereof. [Means for solving the problem]

[0022] In order to solve the above-mentioned problems, the present inventors adjusted the balance of components of a good PCM material that provides a cooling sensation that lasts, and found that a cooling sensation composition composed of a specific component composition exerts the desired effect, thereby completing the present invention.

[0023] That is, a cooling composition comprising (1) to (6) as follows is provided. (1) A cooling composition characterized by containing (a) octadecane and / or (b) polyacrylic acid amide as a phase change material. (2) The cooling sensation composition according to (1), characterized in that the melting point is adjusted to 28°C or less by blending a phase change material composed of (a) 60% to 80% by weight of octadecane and / or (b) 40% to 20% by weight of polyacrylic acid amide. (3) A cooling sensation composition according to (1), characterized in that the duration of the cooling sensation is improved by the two-layer structure, in which the inner layer comprises a continuous layer composed of (a) 80% by weight of octadecane and / or (b) 20% by weight of polyacrylic acid amide in order to adjust the melting point to 28°C or lower, and the outer layer comprises a continuous layer composed of (a) 60% by weight of octadecane and / or (b) 40% by weight of polyacrylic acid amide in order to adjust the melting point to a range of 28°C or lower but higher than the adjustment temperature of the inner layer. (4) The cooling composition according to (1) or (2), which is in the form of a sheet, a column, or a cylinder. (5) The cooling composition according to any one of (1) to (4), which is molded for use in bedding, clothing, or neckwear. (6) The cooling composition according to any one of (1) to (5), which is a preventive product for preventing heatstroke. [Effects of the Invention]

[0024] The cooling sensation composition of the present invention provides a cooling sensation composition characterized by blending (a) octadecane and / or (b) polyacrylic acid amide as a phase change material to form the basis for the cooling sensation properties aimed at by the present invention, and two inventions are constituted and exhibit effects based on the structure of this basis.

[0025] That is, as a first preferred invention, there is provided a cooling composition suitable for preventing heatstroke, which has excellent cooling performance and is characterized by having a melting point adjusted to 28°C or less by blending a phase change material composed of (a) 60% to 80% by weight of octadecane and / or (b) 40% to 20% by weight of polyacrylic acid amide.

[0026] Furthermore, in order to improve the durability of the cooling sensation performance according to the first invention, a preferred second invention provides a cooling sensation composition having a two-layer structure, in which the inner layer has a continuous layer composed of (a) 80% by weight of octadecane and / or (b) 20% by weight of polyacrylic acid amide in order to adjust the melting point to 28°C or lower, and the outer layer has a continuous layer composed of the same as the inner layer, 60% by weight of (a) octadecane and / or (b) 40% by weight of polyacrylic acid amide in order to adjust the melting point to a range of 28°C or lower but not lower than the adjustment temperature of the inner layer.

[0027] The first and second inventions described above are preferably in the form of a sheet, a column or a cylinder, so as to be suitable for a desired application. DETAILED DESCRIPTION OF THE INVENTION

[0028] As described above, the present invention relates to a cooling composition that, due to its specific component composition, exhibits cooling properties useful as a countermeasure against heat stroke and can provide a cooling sensation for a long period of time, and uses thereof.

[0029] That is, according to the present invention, a cooling sensation composition is provided that contains (a) octadecane and / or (b) polyacrylic acid amide as a phase change material to provide a sustained cooling sensation, and two main inventions are provided based on this composition.

[0030] First, we provide a cooling composition characterized by having a melting point adjusted to 28°C or lower by blending a phase change material composed of (a) 60 to 80% by weight of octadecane and / or (b) 40 to 20% by weight of polyacrylic acid amide. Second, we provide a cooling composition with a two-layer structure for long-lasting cooling sensation, in which the inner layer has a continuous layer composed of (a) 80% by weight of octadecane and / or (b) 20% by weight of polyacrylic acid amide to adjust the melting point to 28°C, and the outer layer has a continuous layer composed of (a) 60% by weight of octadecane and / or (b) 40% by weight of polyacrylic acid amide, the same as the continuous phase of the inner layer, to adjust the melting point to a range of 28°C or lower but higher than the adjustment temperature of the inner layer, thereby improving the long-lasting cooling sensation. The following describes the embodiments in detail based on these specific aspects of the invention.

[0031] The present inventors attempted to provide a cooling composition that is optimal for preventing heatstroke by utilizing the cooling mechanism of a cooling device that uses a PCM material. The cooling mechanism of the cooling device is as follows: (1) Phase change phenomenon: PCM materials undergo a phase transition (change from solid to liquid or from liquid to solid) within a specific temperature range, and during this phase transition, thermal energy called latent heat is absorbed and released. (2) Utilizing the cooling effect: The PCM material incorporated into the cooling device is pre-treated to become liquid, which cools the device and absorbs the surrounding heat. (3) Cooling effect when worn: When the cooling device is worn, body heat and environmental heat are transferred to the device, and the PCM material changes from a solid to a liquid state, absorbing latent heat. This allows the device to absorb the surrounding heat and provide cooling. (4) Continuous cooling effect: PCM material has the property of undergoing repeated phase transitions within a certain temperature range. When the PCM material absorbs the surrounding heat while wearing it, it returns to a solid state and releases latent heat. This repeated phase transition provides a continuous cooling effect.

[0032] In this way, cooling devices using PCM materials absorb and release heat from the surrounding area, providing coolness. By utilizing the phase transition within a specific temperature range, the cooling effect can be maintained for a relatively long period of time.

[0033] Generally, PCM materials for cooling devices include paraffin-based PCM, sorbitol-based PCM, and glycerin-based PCM, each of which has its own characteristics.

[0034] For example, the paraffin-based PCM is the most widely used, suitable for general cooling devices, inexpensive, and has a wide melting point range of 30°C to 70°C, making it suitable for use in a wide range of temperatures.

[0035] Sorbitol-based PCMs have a low melting point range (approximately 20°C to 35°C) and provide a cooling effect even at relatively low temperatures, making them suitable for cooling in hot climates and during exercise.

[0036] Glycerin-based PCMs have a low melting point range (approximately 15°C to 30°C) similar to sorbitol-based PCMs, and glycerin is relatively safe for the skin, making it suitable for people with sensitive skin.

[0037] As such, there are various characteristics and types of components, so it is necessary to select the type according to the application, but it is reasonable to combine two or more types to make the most of each characteristic.

[0038] In the present invention, it was discovered that the range in which the skin contact temperature is maintained, which is particularly suitable for preventing heatstroke, is around 28°C, and from this perspective, (a) octadecane and / or (b) polyacrylic acid amide was selected as the PCM material.

[0039] Here, (a) octadecane is a type of hydrocarbon, a straight-chain alkane with 18 carbon atoms (molecular formula: C18H38; melting point: 28°C). It is known to be used as a cooling material, but there are no examples of its application under the specific conditions relevant to the object of the present invention.

[0040] On the other hand, (b) polyacrylamide is a polymer of acrylic acid amide. Polyacrylamide is water-soluble and water-retentive, and its aqueous solution is viscous. Therefore, it is used to adjust viscosity and maintain the emulsion stability of products, particularly in cosmetics and pharmaceuticals, but its use as a PCM material is not generally known.

[0041] The above (a) octadecane and (b) polyacrylic acid amide are highly compatible and can achieve a temperature setting suitable for the cooling device designed by the inventor, so this material was used to construct the device and was used as the basic structure.

[0042] The first invention provides a cooling sensation composition containing a phase change material composed of (a) 60% to 80% by weight of octadecane and / or (b) 40% to 20% by weight of polyacrylic acid amide, in order to adjust the melting point to 28°C to 32°C.

[0043] The second invention provides a two-layer cooling composition. Specifically, the inner layer comprises a continuous layer composed of (a) 80% by weight of octadecane and / or (b) 20% by weight of polyacrylic acid amide to adjust the melting point to 28°C or lower, and the outer layer comprises a continuous layer composed of the same as the inner layer, 60% by weight of (a) octadecane and / or (b) 40% by weight of polyacrylic acid amide to adjust the melting point to 28°C or lower but above the adjustment temperature of the inner layer, thereby providing a cooling composition with improved durability of the cooling sensation.

[0044] In both the first and second inventions, the form is preferably a sheet, a columnar, or a cylindrical shape. Examples of sheet-shaped applied products include those applied partially to the forehead, those embedded in a vest or belt, and those applied to the whole body, such as bedding. A columnar or cylindrical shape is preferably used as a neck ring. Both types of products are optimally usable as products for preventing heatstroke, a recent trend. [Example]

[0045] The present invention will be specifically described below with reference to examples, but the scope of the present invention is not limited to these examples.

[0046] <Test Example 1> Surface temperature test In accordance with the conditions of the present invention, the melting point of the PCM material used in the cooling composition was adjusted, and the surface temperature of the following ice neck rings was measured after solidification to confirm their performance. "Test sample" Sample (1) 28°C (product of the present invention composed of octadecane and water) Sample (2) 28°C (product of the present invention composed of polyacrylamide and water) Sample (3) 28°C (conventional product composed of stearin and tripalmitin; applicant's invention)

[0047] (Test Method) After leaving the samples overnight in a thermo-hygrostat set at 5°C, each sample is transferred to a thermo-hygrostat set at 30°C, and the surface temperature of each sample is measured every 10 minutes for 3 hours.

[0048] (Results and Discussion) As shown in Table 1, it was confirmed that the products of the present invention all have the same cooling capacity as conventional products. Since they maintain the appropriate temperature range required to prevent heatstroke, it can be inferred that they can be designed to be suitable for practical use in the summer. [Table 1] [Table 2]

[0049] <Test Example 2> Appearance and texture test The same sample as in Test Example 1 was used to carry out a confirmation test of appearance and feel. "Test sample" Sample (1) 28°C (product of the present invention composed of octadecane and water) Sample (2) 28°C (product of the present invention composed of polyacrylamide and water) Sample (3) 28°C (conventional product composed of stearin and tripalmitin; applicant's invention)

[0050] (Test Method) After leaving each sample in a thermo-hygrostat set at 5°C for 1 hour, the sample was taken out and immediately thereafter visually inspected for changes in appearance, and the feel when wrapped around the neck was confirmed and evaluated.

[0051] (Results and Discussion) As shown in Table 3, it was confirmed that the conventional products were solid, while the inventive products were liquids with good affinity to the skin. The desired effects aimed at by the present invention were confirmed. [Table 3]

Claims

1. A cooling composition characterized by selecting (a) octadecane and / or (b) polyacrylic acid amide as a phase change material and blending these components with an appropriate amount of (C) water.

2. 2. The cooling sensation composition according to claim 1, wherein the melting point is adjusted to 28°C or less by blending a phase change material composed of (a) 60 to 80% by weight of octadecane and / or (b) 40 to 20% by weight of polyacrylic acid amide with (C) water in an amount of 30% by weight or less based on the total weight of the phase change material.

3. 2. The cooling composition according to claim 1, characterized in that the cooling composition has a two-layer structure, in which the inner layer comprises a continuous layer made of (a) 80% by weight of octadecane and / or (b) 20% by weight of polyacrylic acid amide in order to adjust the melting point to 28°C or lower, and the outer layer comprises a continuous layer made of (a) 60% by weight of octadecane and / or (b) 40% by weight of polyacrylic acid amide in order to adjust the melting point to a range of 28°C or lower but higher than the adjustment temperature of the inner layer, thereby improving the duration of the cooling sensation.

4. 3. The cooling sensation composition according to claim 1, which is in the form of a sheet, a column or a cylinder.

5. 5. The cooling composition according to claim 1, which is molded for use in bedding, clothing, or as a neck wrap.

6. The cooling composition according to any one of claims 1 to 5, which is a preventive product for preventing heat stroke.

Images