JP2002241746A - Chilling composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a chilling composition and a sheet-like chilling preparation each containing a large quantity of water stably and having high chilling effect, particularly sustained chilling effect. SOLUTION: The chilling composition comprises 1-19.5 wt.% of a polyacrylic acid compound, 0.1-17.5 wt.% of an N-vinyl acetamide polymer, 0.05-1 wt.% of a polyvalent metal and >80 wt.% and <=95 wt.% of water. The sheet-like chilling preparation is obtained by laminating a sheet-like substrate with the above composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet-like coolant capable of cooling an object utilizing the latent heat of water by directly or indirectly attaching the object to a human body or other objects, and a sheet-like coolant therefor. The present invention relates to a cooling composition as a substrate.

[0002]

2. Description of the Related Art Wet towels, ice pillows, ice sac or chemical ice sac have been used for a long time to cool the forehead and head during heat generation. In particular, the method using a wet towel is the most commonly used cooling method because of its simplicity.However, the wet towel contains air together with water, so that a layer of air prevents the dissipation of heat, and as a result, the inside of the towel There is a disadvantage that the cooling effect is not sustained due to heat buildup. On the other hand, ice pillows, ice sacs, or chemical ice sacs are excellent in sustained cooling effect, but are disadvantageous in that they take a long time to prepare, do not catch up with sudden heat generation, fall off the forehead when they move, are very easy to use, are hard and difficult to use, etc. There is.

[0003] For this reason, recently, an adhering type coolant obtained by laminating a gel base material for cooling on a sheet-like base material made of a non-woven fabric or the like has been developed. The demand for such products is increasing due to reasons such as difficulty in dropping and a longer lasting cooling effect than wet towels once applied, and various products have been sold by various companies.

[0004] These coolants, like wet towels,
It utilizes the mechanism of lowering skin temperature by using the heat of vaporization of water (see FIG. 1 (A)). Therefore, the cooling base material used in the cooling agent contains a large amount of water. However, natural water-soluble polymers such as tragacanth gum, karaya gum, gum arabic, sodium alginate, mannan, gelatin, pectin, etc., which have self-retaining and adhesive properties, or polyvinyl alcohol (PV
A), a hydrogel base material prepared from polyacrylic acid or a salt thereof, or a synthetic polymer such as carboxyvinyl polymer (CVP) is generally used.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cooling composition excellent in cooling / cooling effect and a sheet-like coolant using the same. In particular, an object of the present invention is to provide a cooling composition excellent in long-term durability, in which an excellent cooling effect is maintained over a long period of time, and a sheet-like coolant using the same.

[0006]

According to the general underheating mechanism shown in FIG. 1, cooling of an object to be cooled such as skin is
Since the moisture contained in the cooling base material evaporates and the heat absorbed from the object to be cooled is radiated from the base material, the base material contains more water to increase the evaporation amount of the water. By doing so, it is thought that a cooling agent that maintains the cooling effect for a longer time can be prepared. The present inventors have been studying the development of a cooling composition and a cooling agent based on this concept, and found that in addition to polyacrylic acids and polyvalent metals, an N-vinylacetamide polymer was used as a base material component. In spite of a decrease in water evaporation (water volatility) as compared with the case where no N-vinylacetamide polymer is used, the cooling effect is surprisingly maintained with a high cooling effect and excellent in long-term durability. It was found that the material could be prepared. Furthermore, the present inventors have found that this cooling composition is not only superior in persistence but also in the initial cooling capacity immediately after use as compared with the case where the N-vinylacetamide polymer is not used, and this cooling composition has It has been confirmed that a coolant that maintains a superior cooling effect over a long period of time can be prepared by using the same. The present invention has been developed based on such knowledge.

That is, the present invention is a cooling composition shown in the following (1) to (3). (1) 1-19.5% by weight of polyacrylic acid, 0.1-17.5% by weight of N-vinylacetamide polymer, 0.05-1% by weight of polyvalent metal and 80% by weight of water Cooling compositions containing more than 95% by weight. (2) The cooling composition according to (1), which has a pH of 4 to 6.5. (3) The cooling composition according to (1) or (2), further comprising at least one selected from the group consisting of polyhydric alcohols, acids, acid salts, fresheners, and high molecular substances.

The present invention further provides the following sheet-like coolant using the above-mentioned cooling composition as a cooling substrate. (4) A sheet-like coolant obtained by laminating the cooling composition according to any one of (1) to (3) on a sheet-like substrate.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The cooling composition according to the present invention comprises 1 to 19.5% by weight of polyacrylic acid and 0.1 to 0.1% of polyvalent metal.
0.5 to 1% by weight of an N-vinylacetamide polymer in an amount of 0.5%.
1-17.5% by weight and more than 80% by weight of water 95
It is characterized in that it is contained at a ratio of not more than% by weight.

Here, the polyacrylic acids include polyacrylic acid, salts of polyacrylic acid and copolymers of acrylic acid and acrylic acid, and polymethacrylic acid, salts of polymethacrylic acid and methacrylic acid. And a methacrylic acid salt. Regarding polyacrylic acids, whether linear or branched,
Although the molecular weight is not particularly limited, those having a molecular weight of 10,000 to 10,000,000 are usually used. From the viewpoint of increasing the gel strength and stably retaining more water,
Particularly, those having a molecular weight of 1,000,000 to 7,000,000 are desirable.

The polyacrylic acid includes not only a polymer obtained by polymerizing ordinary (meth) acrylic acid but also a (meth) acrylic acid polymer such as a carboxyvinyl polymer (Carbopol (registered trademark)). Partially cross-linked ones can also be suitably used.

The salt of poly (meth) acrylic acid is not particularly limited, but is preferably a monovalent metal of poly (meth) acrylic acid such as sodium poly (meth) acrylate and potassium poly (meth) acrylate. Salts; alkanols of poly (meth) acrylic acid such as poly (meth) acrylic acid monoethanolamine, poly (meth) acrylic acid diethanolamine, poly (meth) acrylic acid triethanolamine, poly (meth) acrylic acid methyldiethanylamine Amine salts include ammonium salts of poly (meth) acrylic acid. Preferably poly (meth) such as sodium salt
It is a monovalent metal salt of acrylic acid.

These polyacrylic acids may be used alone or in any combination of two or more. Since polyacrylic acids having a molecular weight of 1,000,000 or more are generally difficult to obtain, when a polyacrylic acid having a molecular weight in the range is used, a salt of polyacrylic acid and polyacrylic acid (for example, a sodium salt) is used. It is desirable to use them in combination. However, this is not the case if it becomes easy to obtain polyacrylic acid having a molecular weight of 1,000,000 or more in the future.

When polyacrylic acid and a salt of polyacrylic acid are used in combination, their mixing ratio is such that the average molecular weight is 200
It is not particularly limited as long as it is adjusted to be at least 10,000, preferably at least 4 million, but specifically, from 0:10 to 9: 1.
(Weight ratio) Preferably, a ratio of 2: 1 to 1: 2 (weight ratio) is exemplified.

The mixing ratio of the polyacrylic acid to 100% by weight of the cooling composition of the present invention is usually 1 to 19.5% by weight, preferably 2 to 12% by weight, and more preferably 3 to 3% by weight.
8% by weight.

In the present invention, polyvalent metals are used for the purpose of broadly including polyvalent metals, salts thereof and polyvalent metal compounds. These polyvalent metals are not particularly limited as long as they are divalent or more and can crosslink the above-mentioned polyacrylic acids, and not only one kind but also a combination of two or more kinds can be used.

The amount of these polyvalent metals to be added to 100% by weight of the cooling composition of the present invention is usually 0.05 to 1% by weight, preferably 0.05 to 0.5% by weight, more preferably 0 to 0.5% by weight. 0.08 to 0.3% by weight. Such polyvalent metals contribute to maintaining the shape retention of the gel. If the compounding ratio is reduced to more than 0.05% by weight, crosslinking becomes insufficient and the strength of the gel becomes insufficient, and the shape retention of the obtained gel body is reduced. Tends to decrease.

As the polyvalent metals, polyvalent metals such as magnesium, calcium, zinc, cadmium, aluminum, titanium, manganese, cobalt and nickel are preferred.
Examples thereof include salts and compounds thereof. From the viewpoints of skin safety, productivity, and gel properties, aluminum, magnesium, calcium or a compound thereof is more preferable, and an aluminum compound is particularly desirable.

Here, aluminum compounds include hydroxides such as aluminum hydroxide and aluminum magnesium hydroxide; and inorganic or organic acids such as aluminum chloride, aluminum sulfate, dihydroxyaluminum aminoacetate, kaolin and aluminum stearate. Normal salts or basic salts thereof; double salts such as aluminum alum; and aluminates such as sodium aluminate, inorganic aluminum complex salts, and organic aluminum chelate compounds, as well as synthetic hydrotalcite and aluminum metasilicate Examples include magnesium acid, aluminum nitrate, aluminum sulfate, EDTA-aluminum, aluminum allantoinate, aluminum acetate, aluminum glycinal and the like. These aluminum compounds may be used alone or in any combination of two or more.

These aluminum compounds may be water-soluble or hardly soluble in water. When an aluminum compound that is hardly soluble in water is used, a crosslinking reaction can be promoted by adding an acid for adjusting the rate to the gel reaction system. Here, as the acid, an organic acid, particularly an organic acid containing a hydroxyl group or a salt thereof can be preferably exemplified. Examples of these crosslinking reaction rate regulators include organic acids such as citric acid, lactic acid, tartaric acid, gluconic acid, glycolic acid, malic acid, fumaric acid, metasulfonic acid, maleic acid, and acetic acid. In addition, organic acid salts or bases having chelating or coordinating ability for metal ions such as sodium EDTA, urea, triethylamine and ammonia, and hydrochloric acid, phosphoric acid, sulfuric acid, nitric acid and hydrobromic acid, etc. Inorganic acids can be used.

The N-vinylacetamide polymer used in the present invention includes a homopolymer of N-vinylacetamide having a repeating unit represented by the following general formula (1):

[0022]

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For example, an N-vinylacetamide copolymer comprising one or more kinds of repeating units represented by the following general formula (2)

[0024]

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(Wherein, R represents a hydrogen atom or a methyl group, and M represents a hydrogen atom or an alkali metal atom) or a crosslinked product thereof.

Here, with respect to the copolymer of N-vinylacetamide, the monomer copolymerizable with N-vinylacetamide used in the present invention not only improves the viscosity of the polymer but also converts the composition into a patch form. Is added for the purpose of giving a crosslinking point at the time of the above-mentioned general formula (2)
Acrylic acid, sodium acrylate, potassium acrylate, methacrylic acid, sodium methacrylate, potassium methacrylate, and the like represented by Further, it is preferable that the repeating unit (1) and the repeating unit (2) are in the range of 50 to 100: 50 to 0% by weight.

The N-vinylacetamide polymer used in the present invention is a crosslinked product of the above homopolymer or copolymer for the purpose of increasing gel strength, imparting structural viscosity and reducing stickiness to the skin. It is desirable that This crosslinked product can be produced by adding a crosslinking agent when polymerizing N-vinylacetamide.

The crosslinking agent is not particularly limited, but includes, for example, N, N-1,4-butylenebis (N-vinylacetamide), N, N-1,6-hexylenebis (N-vinylacetamide), N, N-decylenebis (N-vinylacetamide), N, N-3-oxa-
1,5-pentylenebis (N-vinylacetamide),
N, N-3,6-dioxaoctylenebis (N-vinylacetamide), N, NP-xylenebis (N-vinylacetamide), N, N'-diacetyl-N, N'-
Divinyl-1,4-bisaminomethylcyclohexane,
Tetraallyloxyethane, triallyl phosphate, trimethylolpropane diallyl ether, sucrose allyl ether, N, N'-methylenebisacrylamide, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di ( Compounds having two or more unsaturated groups in one molecule, such as meth) acrylate, polyethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol triallyl ether, divinylbenzene, and divinyl ether Can be

The crosslinking agent is used in a weight ratio of 1/10 to 1/2000, preferably 1/20 to 1/200, based on the total amount of the N-vinylacetamide and the monomer represented by formula (2).
Used in the range of 500.

These N-vinylacetamide polymers may be used alone or in any combination of two or more.

As the N-vinylacetamide polymer, for example, PNVA (GX manufactured by Showa Denko KK)
-205), the same PNVA (NA-010), the same PNVA
Commercially available products such as the (NA-300) series can be used.

The mixing ratio of the N-vinylacetamide polymer to 100% by weight of the cooling composition of the present invention is usually 0.1 to 17.5% by weight, preferably 0.1 to 10% by weight, more preferably 0 to 10% by weight. 0.1 to 3% by weight. If the amount is less than 0.1% by weight, sufficient water retention and skin adhesion tend not to be exhibited.

The cooling composition of the present invention contains water in addition to the above-mentioned components, and has a water content at a standard condition of more than 80% by weight and 95% by weight or less per 100% by weight of the final composition. Preferably, it is more than 80% by weight and 90% by weight or less, more preferably more than 80% by weight and 85% by weight or less.

The composition has a moisture releasing property in which the water content is gradually evaporated from the surface over time. For this reason, based on the fact that the latent heat of evaporation during moisture evaporation is deprived, the composition always keeps a temperature lower than room temperature, and when the composition is applied to a cooling object such as skin, the composition evaporates from the cooling object. The object to be cooled can be cooled by removing heat in the form of latent heat. As described above, since the water contained in the composition is the main source of the cooling action, it is considered that the greater the content, the better the cooling effect.

The above-mentioned N-vinylacetamide polymer exhibits an excellent water-retaining ability in the composition of the present invention, so that a large amount of water as described above is retained in the cooling composition of the present invention. Becomes possible. The cooling composition of the present invention is not only excellent in the initial cooling effect immediately after use (pasting), but also has an exceptionally excellent cooling effect such that the excellent cooling effect is maintained for a long time.
As shown in Experimental Example 2 described later, it is considered that this effect is not merely due to the large water content but is largely due to the inclusion of the N-vinylacetamide polymer. The N-vinylacetamide polymer itself has a high water retention (water retention), and as shown in Experimental Example 1, it is generally mixed with it to evaporate (evaporate) water in the application system. Is suppressed. On the other hand, it is the conventional recognition that the cooling action of the coolant of the class of the present invention is caused by the dissipation of heat of vaporization together with the evaporation of moisture from the cooling base material. It is considered that the more water vaporized (evaporated) from the cooling base material, the higher the cooling effect. Considering these facts, the present invention shows that in a system in which water evaporation (evaporation) is suppressed by blending an N-vinylacetamide polymer, the initial and long-term cooling effects are significantly improved as compared with a system not blended with N-vinylacetamide polymer. Can be said to be a surprising effect that cannot be expected from the conventional common sense described above.

The cooling composition of the present invention may contain any of the above-mentioned components, but may further contain a polyhydric alcohol. Such a polyhydric alcohol is useful as a dispersion medium for polyacrylic acids, and also serves as a binder for dispersing and emulsifying an oil component such as l-menthol in water, and further imparts moisturizing properties and wettability, and provides a feeling of use. Contribute to improvement.

The polyhydric alcohol is not particularly limited by the shape such as linear or branched, the molecular weight, etc., and any one which is generally used as long as it is safe for the object to be cooled is used. be able to. Specific examples include glycerin, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, and the like.
Among them, glycerin, propylene glycol, dipropylene glycol and butylene glycol are preferred. These may be used alone or in combination of two or more.

The proportion of the polyhydric alcohol to be added to the cooling composition of the present invention is appropriately selected from the range of usually 0 to 18% by weight per 100% by weight of the cooling composition. Preferably, it is in the range of 2 to 15% by weight and 5 to 10% by weight.

The cooling composition of the present invention may further contain a cellulose derivative.

The addition of the cellulose derivative is useful in improving the processability of the composition of the present invention showing a non-Newtonian fluid, improving the stability of the gel, and simplifying the adjustment of the viscosity.

The cooling composition of the present invention may further contain a polymer.

The compounding of the polymer substance is useful in improving the processability of the composition of the present invention showing a non-Newtonian fluid, improving the stability of the gel, and simplifying the adjustment of the viscosity.

Such high-molecular substances include cellulose or its derivatives, starch or its derivatives, and vinyl-type high-molecular compounds. Specifically, as a derivative of cellulose, carboxymethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxymethylethylcellulose, hydroxypropylcellulose, hydroxypropylcellulose phthalate methylcellulose, cellulose acetate, cellulose acetate hydroxymethylethylcellulose, methylcellulose, ethylcellulose or an alkali thereof Metal salts and the like; carboxymethyl starch and hydroxypropyl starch as starch derivatives; and polyvinyl alkyl ethers as vinyl polymer compounds;
Polyvinyl alcohol, polyvinyl acetate, methyl vinyl ether / maleic anhydride copolymer, polyvinylpyrrolidone, carboxylvinyl polymer, vinylpyrrolidone / vinylalkylaminoacrylic acid copolymer, styrene maleic acid copolymer, ethylene-vinyl acetate copolymer A polymer and a vinyl acetate-polyvinyl alcohol copolymer can be exemplified. These can be used alone or in combination of two or more. Preferably, it is cellulose or a derivative thereof, and more preferably, a sodium salt of carboxymethyl cellulose.

The amount of these high molecular substances is appropriately selected from the range of 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, per 100 parts by weight of the composition.

In the cooling composition of the present invention, other polymers other than those described above can be added and blended, and these can be sufficiently compatible with the above-mentioned components or become cloudy. Preferably, they are compatible to a certain extent. For example, these polymers include rubber-based thickening substances such as silicone rubber, acrylic rubber, and natural rubber; guar gum,
Thickening polysaccharides such as locust bean gum, pullulan, etc .; (meth) acrylate-based adhesive substances containing alkyl (meth) acrylate as a main component; and polyether-based thickening substances such as polyethylene oxide. .
Preferably, these are added to such an extent that the physical properties of the cooling composition of the present invention are not affected.

The cooling composition of the present invention may further contain, if necessary, a preservative, a preservative, a stabilizer, a fragrance, a coloring agent, in addition to the above-mentioned components, as long as the physical properties thereof are not affected. pH adjuster, limonene, camphor, peppermint oil or l
-A cooling agent such as menthol, a humectant, a stimulant, a disinfectant, an antibacterial agent, a tackifier, a shape retaining agent, a thickener and the like can be blended.

It is preferable that the cooling composition of the present invention generally has an acidic to weak acidity from the viewpoint of shape retention and cooling action. Preferably pH 4-6.5, more preferably pH 4.
It is desirable to have a pH of 5-6. PH adjusters used to adjust the composition to such a pH range include tartaric acid, citric acid, phosphoric acid, lactic acid, gluconic acid, glycolic acid, malic acid, fumaric acid, methsulfonic acid,
Examples thereof include organic acids such as maleic acid, acetic acid, and ethylenediaminetetraacetic acid, and inorganic acids such as hydrochloric acid, phosphoric acid, sulfuric acid, nitric acid, and hydrobromic acid.

The cooling composition of the present invention is produced by mixing each component of the composition and dissolving it in water. For example, specifically, a composition containing a polyacrylic acid, an N-vinylacetamide polymer and a polyvalent metal is dispersed or dissolved, and the composition is gradually added to water and kneaded to form a gel. The method for preparing can be exemplified. Also,
The manufacturing process may include a degassing process. The degassing method is not particularly limited, but is preferably degassing by a physical treatment such as mesh filtration degassing or vacuum degassing from the viewpoint that the dispersion density of the solvent system is not increased. Qi is preferred.

The cooling composition of the present invention is excellent in endothermic effect and can exhibit its excellent cooling effect continuously based on its high water content and containing N-vinylacetamide polymer. . Further, the cooling composition of the present invention can stably retain a large amount of water, and therefore does not exude the contained water even when compressed.
Even when the water content is as high as 5% by weight, it does not enter a fluidized state due to a decrease in consistency, and in this respect, it has a characteristic of being excellent in self-retaining property. In addition, it has a suitable elasticity and strong adhesiveness even in a high water-containing state, and in this respect, it has a feature that it does not select an application target or a sticking place. In particular, this excellent adhesiveness is due to the inclusion of the N-vinylacetamide polymer, and by containing this component, it exerts strong adhesiveness even on cosmetic-applied skin or oily skin. be able to. Further, the cooling composition of the present invention is useful in that it has no irritation and can be safely stuck to the skin and used, and can be easily peeled off without remaining.

Based on such properties, such a cooling composition can be used as a cooling medium for a cooling agent, which can be directly attached to an object to be cooled by utilizing its adhesiveness. Further, it can be used as a base material for a medicated patch (preparation for transdermal absorption) which is also used for cooling.

Such a substrate can be molded and prepared as a sheet-like coolant by itself. However, in consideration of handleability and usability, the cooling composition is applied and spread on a sheet-like substrate. In other words, it is preferable to have a form in which a layer made of the cooling composition is laminated on a sheet-like substrate.

Accordingly, the present invention provides a sheet-like coolant having such a form.

Here, the sheet-like substrate is capable of supporting the above-mentioned cooling composition, and has an appropriate moisture permeability so as not to hinder the moisture release (water evaporation) of the cooling composition. There is no particular limitation as long as it is a material, and various woven fabrics, nonwoven fabrics, films and the like can be used.

When a woven or nonwoven fabric is used as the base material, the material is not particularly limited.
Natural fibers such as hemp and wool; cellulosic fibers such as rayon and acetate; synthetic fibers such as nylon, vinylon, styrene, polypropylene, polyethylene, polyethylene terephthalate and acrylic; and natural fibers such as cotton, hemp and wool. When using a film as the substrate, the material is not particularly limited, but specifically, styrene, polypropylene, polyethylene terephthalate,
Examples include polyethylene.

The thickness of the sheet-like base material is not particularly limited as long as the moisture-releasing property of the cooling composition is not hindered.
Usually, it is 1 to 1000 μ, preferably 10 to 500 μ.

It is preferable that the sheet-like base material has an appropriate elasticity so that when the coolant is applied to the skin, it conforms to the outer shape of the application site.

The thickness of the pressure-sensitive adhesive cooling composition formed by coating, spreading and laminating on such a sheet-like substrate is not particularly limited.
It is 0.00000, preferably 500-5,000.

The sheet-like coolant of the present invention basically comprises
Although it consists of a cooling composition and a sheet-like substrate, from the viewpoint of handleability and hygiene, if necessary, a release film that is removed and removed at the time of use should be laminated on the surface of the cooling composition. Is preferred.

The release film is not limited, but may be polyester, polypropylene, polyethylene,
Nylon, vinyl chloride, polyethylene terephthalate and the like can be used.

The external shape of the sheet-like coolant of the present invention is not particularly limited, and it can be appropriately selected and prepared according to the application object, the sticking place and the like.

The sheet-like cooling agent of the present invention can be produced according to a conventionally known method using the cooling composition prepared as described above. A method in which the composition is uniformly spread-coated on the substrate and a sheet-like substrate is laminated thereon. In this case, the laminate can be pressed by a roller in order to further fix the laminate.

The sheet-like coolant of the present invention is not only applied to the forehead at the time of heat generation, but also cools eyes, chins, legs, feet, etc., and provides an emergency coolant and muscular for bruises and sprains. It can be used as an analgesic and sedative aid for pain, for cooling down muscles after sports, can be cooled immediately without any hassle, can be used disposably, and can be used for a long time This is useful in that the cooling effect is maintained over a long period of time. Further, the cooling patch of the present invention,
Pharmaceutical products such as transdermal preparations (pastes and cataplasms); daily necessities (drinks, foods, cosmetics, and medical use) that are expected to have a cooling effect such as a freshness-preserving agent and a cold-holding agent; It can also be used as cosmetics such as packs that are expected to be used.

[0063]

EXAMPLES The contents of the present invention will be specifically described with reference to the following examples, comparative examples, and experimental examples, but the present invention is not limited to these examples. Unless otherwise specified,% means weight% in the following Examples and the like. Examples 1 and 2, Comparative Examples 1 and 2

[0064]

[Table 1]

Each cooling composition was prepared according to the formulation shown in Table 1. Specifically, for Example 1 and Comparative Examples 1 and 2, sodium polyacrylate and a crosslinked N-vinylacetamide polymer (hereinafter, also simply referred to as NVA) in a mixture of concentrated glycerin and dipropylene glycol, The components of the dried aluminum hydroxide gel, polyvinyl alcohol and carboxyvinyl polymer were dispersed and mixed, and this was gradually added to purified water and kneaded. Next, L-menthol (a cooling agent) and a coloring agent are added thereto, and adjusted to each pH with L-tartaric acid (a pH adjuster).
A cooling composition was obtained. In Example 2, each component of the polyacrylic acid / Na polyacrylate copolymer, the crosslinked product of N-vinylacetamide polymer, the dried aluminum hydroxide gel, and the preservative was mixed, and this was gradually added to purified water. It was added and kneaded. Next, L-tartaric acid (pH adjuster) was added thereto to adjust the pH to 5.5 to obtain a cooling composition. Each of the cooling compositions thus obtained was used as a cooling substrate as a release paper made of polypropylene (5 cm × 11
cm) was coated with a knife coater to a thickness of about 4 mm, and a nonwoven fabric was pressed thereon to prepare a sheet-like coolant (Examples 1 and 2, Comparative Examples 1 and 2).

EXPERIMENTAL EXAMPLE 1 Moisture Retaining Ability (Moisture Volatility) Using the sheet-like coolant of Example 1 (with NVA) and Comparative Example 1 (without NVA), the cooling composition used for each patch was prepared. Water holding power, in other words, water volatility (evaporation) was compared. Specifically, the temperature of each patch was 25 ° C,
The weight of the cooling composition was measured over time by leaving it in an environment with a humidity of 50 to 60%, and the water retention capacity (water volatility) of the cooling composition used was evaluated from the weight loss. The results are shown in FIG.

As can be seen from the results shown in FIG. 2, the cooling composition containing the crosslinked N-vinylacetamide polymer (Example 1) was compared with the cooling composition containing no N-vinylacetamide polymer (Comparative Example 1). Thus, the volatilization (evaporation) of water was significantly slow, indicating that the water retention ability was excellent.

Experimental Example 2 Cooling Effect by N-Vinylacetamide Polymer (NVA) The cooling effect of each sheet-like coolant of Example 1 (with NVA) and Comparative Example 1 (without NVA) was compared. Specifically, each patch was placed on a hot plate set so that a current of 0.7 W always flows, and the temperature was measured over time on a hot plate immediately below the patch. The measurement was terminated when the cooling power of the patch was completely lost and the temperature did not rise, and the temperature at that time was defined as the end point temperature. From the following formula, the cooling temperature at each measurement point was obtained, and the cooling temperature was -2 ° C.
The time maintained below was evaluated as an effective cooling time (hour) in which an effective cooling effect was exhibited.

<Equation> Cooling temperature (° C.) = (Temperature at each measurement time−End point temperature) +4 In the above equation, 4 is added at the end because the metal plate of the hot plate is different from human skin. This is because the specific heat is different and the cooling temperature tends to fall, so that it is suitable for application to actual human skin.

FIG. 3 shows the results. As can be seen from FIG. 3, the effective cooling time of the sheet-like coolant containing no N-vinylacetamide polymer cross-linked product (NVA) (Comparative Example 1) was about 6 hours, whereas the sheet containing NVA did not. The effective cooling time of the liquid coolant (Example 1) is about 8 hours,
It is understood that the cooling effect is remarkably maintained by adding VA. Regarding the cooling temperature immediately after use (initial stage), the cooling temperature of Comparative Example 1 containing no NVA was −4 ° C., whereas that of the patch of the present invention containing NVA (Example 1) was −5. It was 5 ° C., and it was found that the initial cooling effect was remarkably excellent by containing NVA, and this excellent cooling effect was maintained for a long time. That is, according to the cooling composition containing NVA, it is possible to prepare a long-lasting coolant which is excellent not only in the cooling effect immediately after use but also in the cooling effect in long-time use.

As shown in Experimental Example 1, the cooling composition containing NVA is less water-volatile than the cooling composition containing no NVA. The excellent cooling effect cannot be explained only by the principle of heat of vaporization, which has been conventionally considered as a mechanism of lower heat. Although not restricted, heat circulation probably occurs inside the cooling composition (FIG. 1 (B)), possibly due to the fact that the thermal conductivity of the cooling composition is further improved by containing NVA (FIG. 1 (B)). It is thought that the cooling power becomes stronger by combining with cooling. Experimental Example 3 Cooling Effect by pH Example 1 (with NVA, pH 5.5) and Comparative Example 2 (N
The cooling effect of each sheet-like coolant having VA and pH 7) was compared in the same manner as in Experimental Example 2.

FIG. 4 shows the results. As can be seen from FIG. 4, the effective cooling time of the sheet-like coolant (Comparative Example 2) in which the cooling composition was adjusted to pH 7 was about 6 hours, whereas the cooling composition was adjusted to pH 5.5. The effective cooling time of the obtained sheet-like coolant (Example 1) is about 8 hours, and it can be seen that the cooling effect is remarkably maintained by adjusting the pH to the acidic side. From these results, according to the cooling composition whose pH is adjusted to be acidic to weakly acidic such as 5.5, it is possible to prepare a long-lasting coolant excellent in cooling effect in long-term use. found.

Experimental Example 4 Adhesive Strength Test Each sheet-like coolant of Example 1 (with NVA) and Comparative Example 1 (without NVA) was evaluated for adhesive strength to skin. Specifically, as a skin sample, artificial leather (sample 1) as a sample imitating the scalp, and an artificial leather (cosmetic (foundation) applied to the surface as a sample simulating makeup or other oily skin (foundation)) Samples 2) were prepared, and the above-mentioned sheet-like coolant was attached to the surfaces of these samples. The cooling agent was placed on a horizontal surface with the artificial leather facing upward, and a constant load (1 kg) was applied from above (artificial leather side) for 10 seconds. After 10 seconds, remove the coolant from the artificial leather and fix it on a horizontal base with double-sided tape with the non-woven fabric side down,
100g / cm 2cm ² (contact area) cylindrical metal rod from above
^The resistive force against the bar when pressed against with a load of ² and pulled up again was measured as the adhesive strength.

Table 2 shows the results.

[0075]

[Table 2]

As can be seen from the results, the sheet-like coolant prepared by blending the N-vinylacetamide polymer crosslinked product (NVA) with the cooling substrate (Example 1) was prepared without blending it. Compared with the sheet-like coolant (Comparative Example 1), the adhesive strength to the skin was significantly higher, indicating that NV
A was considered to be a component that contributes to improving the adhesive strength of the cooling composition in the present invention. In particular, from the results for the specimen 2, it is found that the cooling agent not containing NVA (Comparative Example 1) significantly lowers the adhesive strength to the makeup skin and the oily skin, whereas the cooling agent containing NVA (Example) 1) was almost the same as the above-mentioned adhesive force to the background, and maintained a strong adhesive force. From this, NVA enhances the adhesive force of the cooling composition (cooling substrate) regardless of the presence or absence of cosmetics, oils, etc. on the surface of the object to be adhered, thereby achieving strong adhesiveness. You can see the contribution.

Experimental Example 5 Evaluation of Safety The sheet-like coolant produced in Examples 1 and 2 was applied to the skin of the leg of an adult male, and the skin on the applied part was observed to determine whether there was any redness, paleness, edema, etc. And the presence or absence of complaints of abnormal sensations such as itching and tingling. As a result, no abnormality was observed, and the safety of the sheet-like coolant of the present invention on the skin was confirmed.

[0078]

The cooling composition of the present invention is excellent not only in the initial cooling effect (cooling power) immediately after use, but also in the excellent cooling effect for a long time, and is excellent in the cooling durability. . Therefore, the cooling composition of the present invention is used as various cooling agents or cooling agents for the purpose of cooling or cooling, and as a cooling substrate for sheet-like cooling agents (pastes, packs, sheet materials). be able to. Further, the cooling composition of the present invention has a water holding power, self-retaining property and adhesiveness,
Furthermore, since it is less irritating to the skin, it can be directly applied to human skin as an adhesive cooling substrate. According to such a cooling composition, a long-lasting coolant in which an excellent cooling effect is maintained for a long time from the beginning can be prepared.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 (A) shows the mechanism of lower heat (a sheet-like coolant, a wet towel, a chemical ice pillow)
Ice pillow / ice sac). (B) in the figure shows the mechanism of the estimated underheating for the sheet-like coolant of the present invention.

FIG. 2 shows the results of a comparison experiment over time of the weight loss (water holding power (water volatility)) of the sheet-shaped coolant of Example 1 (with NVA) and Comparative Example 1 (without NVA) in Experimental Example 1. FIG.

FIG. 3 is a diagram showing the results of a comparison experiment over time of the cooling effect of the sheet-shaped coolant of Example 1 (with NVA) and Comparative Example 1 (without NVA) in Experimental Example 2.

FIG. 4 shows the results of Example 1 (with NVA, p
FIG. 12 is a diagram showing the results of a comparative experiment over time of the cooling effect of the sheet-shaped coolant of Comparative Example 2 (N5.5 with NVA, pH 7).

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08L 39/00 C08L 39/00 C09K 5/06 C09K 5/06 Z F-term (Reference) 4C099 AA02 CA03 CA04 GA02 HA05 HA09 LA14 LA16 4J002 AB013 AB023 AB043 BG01W BJ00X CH023 DD076 DE076 DE146 DE186 DF036 DG046 DH027 DJ036 EC047 EC057 EF027 EF077 EG046 FD140 FD330 GB00

Claims (4)

[Claims] 1. A polyacrylic acid comprising 1 to 19.5% by weight,
A cooling composition containing 0.1 to 17.5% by weight of an N-vinylacetamide polymer, 0.05 to 1% by weight of a polyvalent metal, and water in an amount of more than 80% by weight and 95% by weight or less. . 2. The cooling composition according to claim 1, which has a pH of 4 to 6.5. (3) at least one selected from the group consisting of polyhydric alcohols, acids, acid salts, fresheners and high molecular substances;
3. The cooling composition according to claim 1 or 2, comprising a seed. 4. A sheet-like coolant obtained by laminating the cooling composition according to claim 1 on a sheet-like substrate.