JP3883154B2 - Cooling gel sheet - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cooling gel sheet to be applied when heat is generated. More specifically, the present invention relates to a cooling gel sheet that can maintain a cooling action for a long time.
[0002]
[Prior art]
In the case of sudden fever in infants, cooling to a wet cloth is a long-standing treatment. However, such moisture-containing cloth has a short cooling time and needs to be replaced frequently, and it is only placed on the forehead and is not sticky to the skin. It was necessary to replace the wet cloth.
[0003]
Under such circumstances, a cooling gel sheet in which a water retaining layer made of a contained polymer gel is provided on a support such as a nonwoven fabric has been developed and is already on the market. Such a cooling gel sheet is sticky to a cooling part such as the forehead because the water-containing polymer gel is sticky, so that it does not peel off even if the infant moves, and the cooling gel sheet has a cooling time as it is. Can be left unattended.
[0004]
Such a cooling gel sheet is composed of a support formed of a nonwoven fabric or the like, and a water-containing polymer gel layer provided on the surface of the support, and the evaporation of water when water in the water-containing polymer gel layer evaporates. Cool by heat. Therefore, as the amount of water contained in the water-containing polymer gel layer increases, the cooling time becomes longer.
[0005]
Such a water-containing polymer gel layer is generally formed by blending a water-containing polymer such as gelatin or glycerin with a highly water-containing polymer such as an acrylic resin-based water-absorbing polymer. The water content of this layer is usually Is about 70 to 90% by weight. The cooling time by the water-containing polymer gel layer having such a water content is about 2 hours. If the water content is further increased, the allowable water content of the water-absorbing polymer will be exceeded, and the stability of the water-containing polymer gel layer will deteriorate, for example, the water-absorbing polymer gel layer will stick to the skin side, etc. Inconvenience arises.
[0006]
Therefore, it was necessary to replace the conventional cooling gel sheet approximately every 2 hours. In addition, recently, a cooling gel sheet has started to be marketed in which a high water-absorbing polymer is used to increase the water content of the water-containing polymer gel layer and the cooling capacity is maintained for about 4 hours. The polymer gel layer is unstable, and the water-containing polymer gel sticks to the skin side and remains on the skin surface. Also, when actually used, the cooling time is not so long compared to the conventional cooling gel sheet. .
[0007]
OBJECT OF THE INVENTION
An object of the present invention is to provide a cooling gel sheet having a long cooling time. More specifically, an object of the present invention is to provide a cooling gel sheet that can contain water beyond the water-containing ability of the water-containing polymer and has a long cooling time.
[0008]
SUMMARY OF THE INVENTION
The cooling gel sheet of the present invention includes a support and a hydrogel that is disposed on at least one surface of the support and contains 70 to 90% by weight of water, and exhibits a cooling action by transpiration of water from the hydrogel layer. And a water-containing body that supplies water to the gel layer by contraction stress when the gel layer contracts due to evaporation of water from the water-containing gel layer. It is a feature.
[0009]
The cooling gel sheet of the present invention is a new water-absorbing gel layer utilizing the contraction stress generated by the contraction of the water-containing gel layer as the water-containing gel layer is evaporated, and the water-containing gel layer contracts. The cooling time of the cooling gel sheet is extended by supplying moisture to the tube.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Next, the cooling gel sheet of this invention is demonstrated concretely.
As shown in FIG. 1, the cooling gel sheet of the present invention comprises a support 1 and a hydrogel layer 2 provided on at least one surface of the support 1. In addition, the synthetic resin film (not shown) is normally stuck on the surface of this water-containing gel layer, and this synthetic resin film is peeled off when used.
[0011]
The support 1 forming the cooling gel sheet of the present invention is formed of cloth, non-woven fabric, paper or the like so that water from the hydrous gel layer 2 can be evaporated.
The water-containing gel layer 2 formed on the surface of the support 1 is made of a water-absorbing polymer having high water absorption such as sodium polyacrylate, gelatin, and a water retention agent (eg, glycerin, alkylene glycol). In order to increase the cooling sensation, a small amount of L-menthol or the like may be blended. The thickness of such a hydrogel layer is usually 1-5 mm.
[0012]
Each component that forms such a hydrogel layer 2 is formed of a component that does not adversely affect the human body, particularly a component that is not toxic even if an infant passes into the mouth. The sum total of each component which forms such a hydrogel layer 2 is 10-30 weight% normally. Therefore, in the conventional cooling gel sheet, the hydrogel layer contains 70 to 90% by weight of water. When this moisture evaporates, a cooling action is manifested, and this moisture also has the effect of sticking a cooling gel sheet. In conventional cooling gel sheets, the amount of water that can be used for cooling is usually the actual water content. It is about 70% by weight of water contained in the gel layer. And as the water | moisture content contained in a water-containing gel layer transpires, a water-containing gel layer will shrink | contract, and when the water content rate is usually less than 40% by weight, the adhesiveness of the surface decreases and the skin peels off.
[0013]
In the cooling gel sheet of the present invention, focusing on the fact that the cooling gel sheet contracts as the moisture contained in the water-containing gel layer evaporates as described above, and that contraction stress is expressed in the water-containing gel layer by this contraction. A water-containing body is formed in the water-containing gel layer, and water contained in the water-containing body is newly supplied to the water-containing gel layer by the shrinkage stress generated by the transpiration of water, and the cooling action is maintained for a longer time.
[0014]
The water-containing body can supply moisture contained in the water-containing body to the water-containing gel layer as the state of the water-containing body changes due to the compressive stress generated in the water-containing gel layer.
Specifically, shrinkage stress is generated in the water-containing gel layer due to the evaporation of moisture from the water-containing gel layer, so that the state of the water-containing body is changed by using this shrinkage stress and contained in this water-containing body. Moisture can be transferred to the hydrogel layer. For example, the moisture in the water-containing body can be moved to the water-containing gel layer by changing the shape of the water-containing body by the contraction stress generated in the water-containing gel layer or by destroying the water-containing body itself. In addition, the compressive stress generated in the hydrous gel layer causes changes in the properties, state, or form of the hydrous body, or, for example, the partition wall surrounding the hydrous body and partitioning the hydrous body and the hydrous gel is pulled and broken in the package. Moisture contained in can be transferred to the hydrogel layer. Further, the compressive stress generated in the hydrous gel layer may be used, for example, by compressing at least a part of the partition wall surrounding the hydrous body and partitioning the hydrous body and the hydrous gel with the compressive stress generated in the hydrous gel layer. Moisture contained in the body can be transferred to the hydrogel layer.
[0015]
That is, in the cooling gel sheet of the present invention, the water-containing body 3 is formed on the hydrous gel layer 2. For example, as shown in FIG. 1, the water-filling body 3 can be formed from a soft foamed resin in which open cells are formed on the surface of the support 1 and an aqueous medium contained in the soft foamed resin. A so-called sponge can be used as the soft foamed resin. Examples of the soft resin used here include urethane resins, polyamides, polyolefins, polysaccharides and the like. Such a soft resin can be foamed by a known method, and by increasing the expansion ratio, open cells are formed in the soft resin. In the soft resin in which the open cells are thus formed, an aqueous medium (such as water) can be contained at a higher content than the water content in the hydrous gel layer. That is, such a soft foamed resin can contain 100 to 3000 parts by weight, preferably 300 to 700 parts by weight of water with respect to 100 parts by weight.
[0016]
In FIG. 1, the water-containing body 3 is provided in a layered form between the support 1 and the hydrogel layer 2, and when the water-containing body 3 is formed in a layer like this, the thickness of the water-containing body 3 Is usually about 0.1 to 5 mm, preferably about 0.5 to 3 mm. By making the thickness of the layered water enclosure 3 within the above range, sufficient moisture can be supplied to the hydrated gel layer 2 and no uncomfortable feeling is caused when the cooled gel sheet is used. In addition, as shown in FIG. 2, the water-containing body 3 can be formed inside the hydrous gel layer 2 by, for example, recoating the hydrous gel layer 2. Furthermore, as shown in FIG. 3, a plurality of water enclosures 3, 3 can be stacked. Moreover, as shown in FIG. 4, the some water enclosure 3 and 3 can also be arrange | positioned in parallel. In addition, a partition wall (not shown) is provided on the outer periphery of the layered water-filling body 3 so that moisture contained in the water-filling body 3 does not migrate into the water-containing gel layer 2 during storage or transfer. It may be formed. The partition wall can be formed of, for example, a film having a strength that can be crushed by the shrinkage stress of the hydrous gel layer 2 caused by the evaporation of moisture, and at least one by applying external stress before use. It can be formed of a film or the like that can break the part.
[0017]
Furthermore, in the cooling gel sheet of the present invention, instead of forming the layered water-filled body 3 as described above, it may be formed of microcapsules containing an aqueous medium having an outer shell that can be crushed by contraction stress due to shrinkage of the hydrogel layer. it can. Such an aqueous medium-containing microcapsule can be produced, for example, by finely dispersing water in an oily medium in the form of droplets and forming a cured film on the surface of the finely dispersed aqueous medium droplets.
[0018]
For example, the microcapsule prepared as described above is dispersed in the water-containing gel layer-forming component, and this dispersion is applied to the surface of the support 1, for example, to form a microcapsule-shaped enclosure as shown in FIG. A cooling gel sheet having the hydrogel layer 2 in which 3 is dispersed can be formed.
[0019]
In addition, the cooling gel sheet of the present invention may have both a layered water-containing body and a microcapsule-shaped water-containing body.
The hydrated body 3 formed in this way is usually surrounded by a hydrated gel layer so that moisture in the hydrated body 3 is prevented from leaking outside the hydrated gel layer 2.
[0020]
From the water-containing body 3 as described above, moisture is gradually supplied into the water-containing gel layer 2 due to contraction stress generated in the water-containing gel layer 2 due to evaporation of the water in the water-containing gel layer 2. It is possible to maintain the cooling ability and tackiness of the hydrogel layer 2 for a long time by diffusing into the component (for example, a water-absorbing polymer) that forms.
[0021]
Although the cooling gel sheet of this invention has the support body 1, the hydrous gel layer 2, and the water-containing body 3 as mentioned above, the cooling gel sheet of this invention can be further variously modified.
[0022]
For example, in the cooling gel sheet of the present invention, the water-containing gel layer 2 is preferably blended with a bitter component. In other words, the cooling gel sheet of the present invention is formed of a component having low toxicity to the human body, and even if such a cooling gel sheet is eaten or licked, it does not have a particularly adverse effect, but an infant does not have any adverse effects. Therefore, it is preferable to blend the bitter component so as not to eat or lick the cooling gel sheet of the present invention.
[0023]
Examples of bitter ingredients that can be used in the present invention include urea, phenylurea, magnesium sulfate, caffeine, naringin, nicotine, quinine sulfate, picric acid, strychinin, 3-methyl-6-methoxy-8-hydroxy -3,4-dihydroisocoumarin, ibonomeamarone, allantolactone, lactucine, tenurine, helenaline, carnosol. Picrotoxinin, colliamine, malvinin, α-caesarpine, chaparin, fisaline A, gentiobiose, levobrucosan, methyl-β-D-glucopyranoside, gennathiopyruline, swellthiamarin, amarogentin, swellside, asperloside, loganine, plumieride, aucbin, Examples include berbenaline, jasminin, castellin, colcholine, fluoroacetophenine-4′-β-neosperidoside, quassha extract, methylthioadenosine, and denatonium benzoate. By the way, even though it is a bitter component, there are various types of bitterness. That is, the bitterness includes a component that feels repellent bitterness even in a small amount, and a component that does not become repellent bitterness in a small amount and does not become repellent bitterness unless a certain amount is ingested, the cooling gel sheet of the present invention It is desirable that the bitter component blended in the water-containing gel layer is a component that feels repellent bitterness in a small amount. In particular, in the present invention, it is preferable to use a bitter component that feels repellent bitterness at a concentration of 50 ppb or more. Further, the bitter component used in the present invention is preferably one that is as irritating as possible to the skin, mucous membrane and the like.
[0024]
Among these examples, denatonium benzoate is most preferable as a component that feels repellent bitterness in such a small amount.
Denatonium benzoate is a white crystalline material that is colorless but has intense bitterness. This denatonium benzoate can sense taste at 10 ppb and bitterness at 50 ppb. Moreover, the bitterness of this denatonium benzoate is an intense repellent bitterness. No abnormalities were observed in the ocular mucosa even when the 0.05 w / v aqueous solution of denatonium benzoate was applied to the eyeballs of mature rabbits. The 0.05 w / v aqueous solution was used in the forearm from the elbow to the wrist of the adult. The patch test results have confirmed that it does not cause any skin irritation.
[0025]
And since this denatonium benzoate is colorless, there is no change in appearance even if it is added to the hydrous gel layer, and since denatonium benzoate is odorless, there is an unpleasant odor by adding denatonium benzoate, etc. It does not occur.
[0026]
The amount of such a bitter component mixed in the hydrogel layer varies depending on the amount of the bitter component used, but in the case of the above-described denatonium benzoate, the hydrogel layer 2 is usually within a range of 0.5 to 50 ppm. When added in an amount of preferably 10 to 40 ppm, repellent bitterness appears in the hydrated gel layer, and there is no irritation to the skin, mucous membrane and the like of infants.
[0027]
The cooling gel sheet of this invention can be manufactured as follows, for example.
First, the cooling gel sheet of this invention which has a layered water-containing body prepares the gel for application | coating by mix | blending water with the component which forms a water-containing gel layer. Separately, a layered hydrated body containing water is placed on the surface of the support. In addition, you may stick this layered enclosure to a support body. Next, the coating gel prepared as described above can be applied onto the layered water enclosure, and a water-impermeable resin film or the like can be further adhered to the surface.
[0028]
In addition, after coating the coating gel on the support, after placing the layered hydrated body on the coated gel surface, the coating gel is coated on the surface, and the surface is water-impermeable. It can be manufactured by attaching a resin film or the like.
[0029]
Further, in the case of forming a microencapsulated hydrated body, water-containing microcapsules produced using microencapsulation technology are mixed when preparing a coating gel, and this coating gel is placed on a support. Further, it can be produced by applying a water-impermeable resin film or the like to the surface.
[0030]
The cooling gel sheet of the present invention thus formed contains about 1.5 to 5 times, preferably 2 to 3 times as much water as the conventional cooling gel sheet using a water-absorbing polymer, and has a long time. The cooling effect can be maintained.
[0031]
【The invention's effect】
The cooling gel sheet of the present invention has a water-filling body that supplies moisture to the water-containing gel layer due to shrinkage stress due to moisture evaporation, and exceeds the allowable limit of the water-absorbing polymer that forms the water-containing gel layer. A large amount of water can be contained. And since the moisture in the hydrated body is gradually supplied to the hydrous gel layer due to the contraction force due to the transpiration of moisture from the hydrous gel layer, the water-absorbing polymer of the hydrous gel layer does not contain excessive nests and is stable. A hydrogel layer can be formed. Therefore, the cooling gel sheet of the present invention has a longer cooling effect than the conventional cooling gel sheet and becomes unstable because the water-containing gel layer contains excessive moisture, and a part of the water-containing gel layer peels off. There is no inconvenience of sticking to the skin.
[0032]
In addition, by blending a repellent bitter component in the water-containing gel layer of the cooling gel sheet of the present invention, even if an infant puts it in the mouth, it will be discharged due to the repellent bitterness and prevent the misuse of the cooling gel sheet. it can.
[0033]
In particular, a cooling gel sheet containing denatonium benzoate as a bitter component is a very small amount of denatonium benzoate, and develops intense repellent bitterness, and does not cause irritation to the skin or mucous membranes or toxicity to the human body.
[0034]
【Example】
EXAMPLES Next, the present invention will be described in more detail with reference to examples of the present invention, but the present invention is not limited thereto.
[0035]
[Example 1]
The following components were mixed, purified water was added thereto and mixed well to make 100 parts by weight as a whole.
[0036]
Gelatin 4.0 parts by weight Sodium polyacrylate 7.0 parts by weight Glycerin 18.0 parts by weight Denatonium benzoate 0.01 parts by weight Purified water The remaining support surface is a 1.5 mm thick soft resin made of polyolefin resin. A foam was placed, and 500 parts by weight of water was impregnated with 100 parts by weight of the soft resin foam.
[0037]
Subsequently, the gel of the above composition was applied to a 1 mm thick nonwoven fabric to a thickness of 2 mm to produce a cooled gel sheet.
This cooling gel sheet adhered to the skin and the cooling effect was maintained for 6 hours.
[0038]
In addition, when a part of the gel having the above composition was put in the mouth, significant bitterness was felt.
[0039]
[Comparative Example 1]
In Example 1, a cooling gel sheet was produced in the same manner except that the gel was directly applied to the surface of the support without using the soft resin foam impregnated with water.
[0040]
This cooling gel sheet lost its adhesive force and cooling effect in 2 hours.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of a cooling gel sheet of the present invention.
FIG. 2 is a cross-sectional view showing another example of the cooling gel sheet of the present invention.
FIG. 3 is a cross-sectional view showing another example of the cooling gel sheet of the present invention.
FIG. 4 is a cross-sectional view showing another example of the cooling gel sheet of the present invention.
FIG. 5 is a cross-sectional view showing another embodiment of the cooling gel sheet of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Support body 2 ... Hydrous gel layer 3 ... Water inclusion body

Claims (7)

A support and a water-containing gel layer that is disposed on at least one surface of the support and contains 70 to 90% by weight of water, and exhibits a cooling action by the evaporation of water from the water- containing gel layer, and A cooling gel sheet, characterized in that a water-containing body that supplies water to the gel layer by a contraction stress when the gel layer contracts due to evaporation of water from the water-containing gel layer is formed in the water-containing gel layer. The water-containing body is capable of supplying moisture contained in the water-containing body to the water-containing gel layer in accordance with a change in the state of the water-containing body due to a compressive stress generated in the water-containing gel layer. The cooling gel sheet of description. The state change of the water-containing body is any one of deformation of the water-containing body, change / destruction of the shape of the water-containing body, or destruction of a partition body of the water-containing body and the hydrous gel layer. The cooling gel sheet according to Item 2. The cooling gel sheet according to any one of claims 1 to 3, wherein the water-filled body comprises a soft foamed resin in which open cells are formed and an aqueous medium contained in the soft foamed resin. The cooling gel sheet according to any one of claims 1 to 3, wherein the hydrated body comprises an aqueous medium-containing microcapsule having an outer shell that can be crushed by contraction stress due to contraction of the hydrogel. The cooling gel sheet according to any one of claims 1 to 5, wherein a bitter component is contained in the hydrated gel layer. The cooling gel sheet according to claim 6, wherein the bitter component is denatonium benzoate.

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