Hydrogel composition for a mask base and method for manufacturing a hydrogel using same

Abstract

A hydrogel composition includes 0.1 to 10 wt % of a cross-linking agent, 0.2 to 6 wt % of a gelling polymer, 0.5 to 20 wt % of a polyhydric alcohol, and 70 to 90 wt % of purified water to maintain a form without a supporter, be stable without fluidization even when a hydrogel is immersed in cosmetics or pharmaceuticals, and allow the cosmetics or the pharmaceuticals to be uniformly delivered to skin.

Claims

1. A hydrogel composition for a mask base comprising: 0.1 to 10 wt % of a cross-linking agent based on a total weight of the hydrogel composition, wherein the cross-linking agent is a mixture of an acryl-based cross-linking polymer and a styrene-based copolymer, and wherein the mixture of the acryl-based cross-linking polymer and the styrene-based copolymer is added in a weight ratio of 2:8 to 8:2; 0.2 to 6 wt % of a gelling polymer, based on a total weight of the hydrogel composition; 0.5 to 20 wt % of a polyhydric alcohol, based on a total weight of the hydrogel composition; and 70 to 90 wt % of purified water, based on a total weight of the hydrogel composition.

2. The hydrogel composition of claim 1, wherein the acryl-based cross-linking polymer is a sodium acrylate/C10-30 alkyl acrylate crosspolymer or a potassium acrylate/C10-30 alkyl acrylate crosspolymer.

3. The hydrogel composition of claim 1, wherein the styrene-based copolymer is one or more selected from the group consisting of an acrylate/ethylhexyl acrylate/hema/styrene copolymer, a butylene/ethylene/styrene copolymer, an ammonium acrylate/methylstyrene/styrene copolymer, an N-vinylpyrrolidone/styrene, and a styrene/acrylate copolymer.

4. The hydrogel composition of claim 1, wherein the gelling polymer is one or more selected from the group consisting of galactomannan, glucomannan, guar gum, locust bean gum, poloxamers, agar, algin, carrageenan, xanthan gum, and gellan.

5. The hydrogel composition of claim 1, wherein the polyhydric alcohol is one or more selected from the group consisting of 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 3-chloro-1,2-propanediol, 2-chloro-1,3-propanediol, and glycerin.

6. A method of manufacturing a hydrogel composition for a mask base of claim 1, the method comprising: adding a cross-linking agentto purified water at room temperature and then performing stirring at a temperature of 40 to 85 C. to manufacture an aqueous solution; dissolving a gelling polymer in a polyhydric alcohol at room temperature, adding the polyhydric alcohol containing the gelling polymer to the aqueous solution, and stirring the resulting solution at 40 to 80 C. to manufacture a hydrogel composition; performing compression coating of the hydrogel composition in a thickness of 0.5 to 2 mm; cooling a hydrogel composition layer that is subjected to the compression coating at room temperature to manufacture the hydrogel; and heat-treating the cooled hydrogel at a temperature of 40 to 85 C. for 12 to 36 hours.

7. The method of claim 6, further comprising: molding the heat-treated hydrogel into a target form; and immersing the molded hydrogel in cosmetic or pharmaceutical solutions.

8. The method of claim 6, wherein strength of the cooled hydrogel is 1.5 to 7.0 kg/cm.sup.2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other aspects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

(2) FIG. 1 is a flowchart showing a method of manufacturing a hydrogel according to an embodiment of the present invention; and

(3) FIG. 2 shows stability of hydrogels manufactured according to Example 1 and Comparative Example 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Best Mode

(4) The present invention relates to a hydrogel composition for a mask base, a form of which is maintained without a supporter and has stable properties, even when a hydrogel is immersed in cosmetics or pharmaceuticals, and a method of manufacturing a hydrogel using the same.

(5) Hereinafter, the present invention will be described in detail.

(6) The hydrogel composition for the mask base includes a cross-linking agent, a gelling polymer, a polyhydric alcohol, and purified water, and a functional additive may be further added according to a use.

(7) Each constituent component will be described below in detail.

(8) The cross-linking agent is an acryl-based cross-linking polymer, a styrene-based copolymer, or a mixture thereof, and the content of the cross-linking agent is 0.1 to 10 wt % and preferably 0.5 to 7 wt %. When the content of the cross-linking agent is less than 0.1 wt %, the gel may be suspended, and when the content is greater than 10 wt %, a residue remains on skin and the gel is fluidized.

(9) The acryl-based cross-linking polymer acts as a bridge, forms a thin film to improve adhesion force and maintain moisture when the hydrogel is used on skin, and provides the soft sense of touch to the hydrogel, and specific examples may include a sodium acrylate/C10-30 alkyl acrylate crosspolymer or a potassium acrylate/C10-30 alkyl acrylate crosspolymer.

(10) Further, the styrene-based copolymer is a film former, physical properties of the gel are increased when cross-linking is performed by heat treatment, and specific examples may include one or two or more selected from the group consisting of an acrylate/ethylhexyl acrylate/hema/styrene copolymer, a butylene/ethylene/styrene copolymer, an ammonium acrylate/methylstyrene/styrene copolymer, a styrene/VP copolymer, and a styrene/acrylate copolymer.

(11) The acryl-based cross-linking polymer and the styrene-based copolymer are added in a weight ratio of 2:8 to 8:2 and preferably 3:7 to 7:3.

(12) In the case where the weight ratio of the acryl-based cross-linking polymer and the styrene-based copolymer is outside the range of 2:8 to 8:2, when the hydrogel is used on skin, viscosity is changed to allow the hydrogel to flow down along skin, and absorption qualities are reduced, and thus it is difficult to charge the cosmetics or the pharmaceuticals in the hydrogel.

(13) The gelling polymer adjusts a form and strength of the gel, and specific examples may include one or two or more selected from the group consisting of galactomannan, glucomannan, guar gum, locust bean gum, pluronic, agar, algin, carrageenan, xanthan gum, and gellan. The content of the gelling polymer is 0.2 to 6 wt % and preferably 0.5 to 5 wt %. When the content of the gelling polymer is less than 0.2 wt %, the form of the gel can be maintained but strength of the gel is high and flexibility is reduced, and thus a close contact property to skin is reduced, and when the content is greater than 6 wt %, it is difficult to maintain the form because the gel droops, it is difficult to manufacture the hydrogel due to reduced elasticity, and adhesion to skin is reduced.

(14) The polyhydric alcohol provides flowability to the hydrogel so that the hydrogel comes into close contact with skin and the cosmetics or the pharmaceuticals permeate skin.

(15) Specific examples of the polyhydric alcohol may include one or two or more selected from the group consisting of 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 3-chloro-1,2-propanediol, 2-chloro-1,3-propanediol, and glycerin.

(16) The polyhydric alcohol is used in a content of 0.5 to 20 wt % and preferably 2 to 15 wt %. When the content of the polyhydric alcohol is less than 0.5 wt %, flowability cannot be provided to the hydrogel, and when the content is greater than 20 wt %, the hydrogel may have viscosity.

(17) Further, the functional additive provides stability and functionality to the hydrogel and may be added if necessary, and specific examples may include one or two or more selected from the group consisting of methylparaben, propylparaben, a kojic acid, an -hydroxy acid, imidazolidinyl urea, Twin 80, and retinol.

(18) The functional additive is used in a content of 0.5 to 3 wt % and preferably 1 to 2 wt %.

(19) The content of purified water is 70 to 90 wt % and preferably 75 to 85 wt %. When the content of purified water is less than 70 wt %, even in the case that a temperature is increased, a gel state may not be changed into a fluidization state, and when the content is greater than 90%, the gel is not formed.

(20) Further, the present invention provides a method of manufacturing the hydrogel using the hydrogel composition, and the method will be described with reference to FIG. 1.

(21) The hydrogel is manufactured by the method including adding the cross-linking agent to purified water at room temperature (23 to 27 C.) and then performing stirring at high temperatures to manufacture the aqueous solution in operation S110, adding the gelling polymer to the polyhydric alcohol at room temperature to dissolve the gelling polymer and then adding the polyhydric alcohol containing the gelling polymer to the aqueous solution to manufacture the hydrogel composition in operation S120, performing compression coating of the hydrogel composition in operation S130, cooling a hydrogel composition layer that is subjected to the compression coating at room temperature to manufacture the hydrogel in operation S140, and heat-treating the cooled hydrogel in operation S150. Further, the method further includes molding the heat-treated hydrogel into a target form in operation S160, and immersing the molded hydrogel in the cosmetic or the pharmaceutical solutions in operation S170 after operation S150. Moreover, the functional additive may be further added to operation S110.

(22) During operation S110, the cross-linking agent is added to purified water and then stirred at a temperature of 40 to 85 C. to manufacture the aqueous solution. Purified water and the cross-linking agent are stirred at the temperature of 40 to 85 C. to be easily thermally cross-linked with a mixture manufactured during the following operation S120.

(23) During operation S120, the gelling polymer is separately dissolved in the polyhydric alcohol, added to the aqueous solution manufactured during operation S110, and stirred at 40 to 80 C. for 0.5 to 2 hours to manufacture the hydrogel composition.

(24) When a stirring temperature of the aqueous solution manufactured during operation S110 and the mixture manufactured during operation S120 is less than 40 C., since the gelling polymer is not dissolved well, physical properties of the hydrogel are reduced, and when the stirring temperature is greater than 80 C., since viscosity of the hydrogel composition is increased, it is difficult to obtain a form and strength is reduced.

(25) Further, when a stirring time is less than 0.5 hours, since the gelling polymer is not uniformly dissolved, strength of the hydrogel is reduced, and when the stirring time is greater than 2 hours, since a gelling ratio of a polymer chain is reduced, strength of the hydrogel is reduced.

(26) During operation S130, compression coating of the hydrogel composition is performed in a thickness of 0.5 to 2 mm by using a roll coater device to form the hydrogel composition layer. When a thickness of the hydrogel composition layer is less than 0.5 mm, since the thickness is small, the hydrogel is torn when the hydrogel adheres to skin, and since the amount of the cosmetics or the pharmaceuticals permeating the gel is small, the cosmetics or the pharmaceuticals are not sufficiently delivered to skin, and when the thickness is greater than 2 mm, since the thickness is large, the hydrogel provides the sense of uncomfortableness and flows down when the hydrogel adheres to skin.

(27) As another example, a film may be compression-coated with the hydrogel composition in a thickness of 0.5 to 2.0 mm by a compression coating device to form the hydrogel composition layer. In this case, the film is not particularly limited as long as the film is easily stripped from the hydrogel and does not affect physical properties of the hydrogel, but a polyethylene terephthalate (PET) film may be used. Further, a non-woven fabric may be provided on another surface of the hydrogel composition layer provided with the film on a surface thereof.

(28) During operation S140, the hydrogel composition layer that is subjected to compression coating is cooled at room temperature for 0.5 to 48 hours to manufacture the hydrogel. When cooling is performed for a period of time of less than 0.5 hours, the hydrogel composition layer having a fluidized phase does not have a form.

(29) During operation S150, a cooled sheet is heat-treated in a drier at 40 to 85 C. for 12 to 36 hours in order to sufficiently charge the cosmetics or the pharmaceuticals in the hydrogel. When a heat treatment time is less than 12 hours, since heat treatment is not ensured, strength is similar to that of a hydrogel in the related art, and hydration or fluidization of the gel occurs when the cosmetics or the pharmaceuticals permeates, and thus the hydrogel cannot be used, and when the heat treatment time is greater than 36 hours, since the hydrogen is excessively dried, a permeation time of the cosmetics or the pharmaceuticals is increased.

(30) The hydrogel manufactured during operation S160 is molded into a target form during operation S160, and the liquid cosmetics or pharmaceuticals are charged in the molded hydrogel during operation S170.

(31) The hydrogel provided according to the present invention has strength of 1.5 to 7 kg/cm.sup.2.

(32) Further, the hydrogel of the present invention may be maintained in form without a separate base therein, and is maintained in form without fluidization of the gel even when the hydrogel is immersed in the cosmetics or the pharmaceuticals.

(33) The film may be provided on a surface of the hydrogel manufactured using compression coating of the hydrogel composition in order to prevent damage to the hydrogel during transportation, and the non-woven fabric may be provided on another surface thereof in order to sufficiently absorb the cosmetics or the pharmaceuticals.

(34) When the cosmetics or the pharmaceuticals are charged in the hydrogel, the cosmetics or the pharmaceuticals are infiltrated into the non-woven fabric to permeate the hydrogel, thus being uniformly charged in the surface of the hydrogel.

(35) Further, when the hydrogel provided with the film and the non-woven fabric is used, the non-woven fabric and the film are separated and only the hydrogel is used.

Mode for Invention

(36) Examples will be given hereinafter to help understanding of the present invention, but the following Examples have been described in an illustrative manner, and it is to be understood that various modifications and amendments will be apparent to those skilled in the art without departing from the spirit of the invention, and the modifications and the amendments naturally fall into the scope of the appended claims.

Example 1

(37) 2 wt % of the sodium acrylate/C10-30 alkyl acrylate cross polymer as the acryl-based cross-linking polymer and 3 wt % of the styrene/VP copolymer as the styrene-based copolymer were added to 72 wt % of purified water, and then stirred at 60 C. Separately, 2 wt % of carrageenan, 0.5 wt % of xanthan gum, and 0.5 wt % of locust bean gum as the gelling polymer were mixed with 20 wt % of glycerin as the polyhydric alcohol, added to the aqueous solution, and stirred at 70 C. for 2 hours to manufacture the hydrogel composition.

(38) After compression coating of the manufactured hydrogel composition was performed in a thickness of 1.0 mm by using the roll coater device, the hydrogel composition was cooled at room temperature for 1.5 hours. The cooled sheet was heat-treated in the drier (Sejong Scientific, Co., Ltd., DRY OVEN SJ-201DL) at 50 C. for 13 hours to manufacture the hydrogel.

Example 2

(39) The same procedure as Example 1 was performed to manufacture the hydrogel, except that 3 wt % of the potassium acrylate/C10-30 alkyl acrylate crosspolymer as the acryl-based cross-linking polymer, 4 wt % of the styrene/acrylate copolymer as the styrene-based copolymer, 70.2 wt % of purified water, 20 wt % of glycerin, and 1.8 wt % of carrageenan and 1.0 wt % of glucomannan were used as the gelling polymer.

Example 3

(40) The same procedure as Example 1 was performed to manufacture the hydrogel, except that 6 wt % of the butylene/ethylene/styrene copolymer as the styrene-based copolymer was used as the cross-linking agent, and 17 wt % of the polyhydric alcohol, 74.7 wt % of purified water, and 1.0 wt % of carrageenan, 0.8 wt % of xanthan gum, and 0.5 wt % of glucomannan were used as the gelling polymer.

Example 4

(41) The same procedure as Example 1 was performed to manufacture the hydrogel, except that 5 wt % of the sodium acrylate/C10-30 alkyl acrylate cross polymer as the acryl-based cross-linking polymer was used as the cross-linking agent, and 71.4 wt % of purified water, 20 wt % of glycerin, and 2.3 wt % of carrageenan, 0.5 wt % of algin, and 0.8 wt % of locust bean gum were used as the gelling polymer.

Comparative Example 1

(42) The same procedure as Example 1 was performed to manufacture the hydrogel, except that the acryl-based cross-linking polymer and the styrene-based cross-linking polymer are not used, and 20 wt % of glycerin as the polyhydric alcohol, and 2 wt % of carrageenan, 0.5 wt % of xanthan gum, and 0.5 wt % of locust bean gum as the gelling polymer were dispersed in 77 wt % of purified water.

Test Example

(43) The liquid cosmetics were impregnated in the hydrogel manufactured in the Examples and the Comparative Examples to measure physical properties, and the results are described in the following Table 1.

(44) 1. Absorbancy of the hydrogel: After the manufacturing initial weight of the manufactured hydrogel was measured, the weight after the hydrogel was deposited in the cosmetics or the pharmaceuticals for one day (weight after deposition) was measured to evaluate absorbancy calculated by the following Equation.
Absorbancy(%)={(weight after depositioninitial weight)/(initial weight)}100[Equation]

(45) 2. Stability: The hydrogel was cut to have a size of 2 cm2 cm and then immersed in the phosphate buffer solution (pH 7.4, 80 ml), and the physical change of the gel (fluidization of the gel) was measured in the shaking incubator rotating at 200 rpm under the condition of 37 C. by the naked eye after 60 minutes, 5 hours, 10 hours, and 24 hours, and evaluated based on the following evaluation standard.

(46) : Maintenance of properties

(47) O: The gel is fluidized in an area of less than 10% of the total area

(48) : The gel is fluidized in an area of less than 30% of the total area

(49) : The gel is fluidized in an area of less than 50% of the total area

(50) X: The gel is fluidized in an area of less than 70% of the total area

(51) 3. Strength: Compressive strength of the gel was measured by using the SUN Rheo Meter Compac-100 II (Sun Scientific Co., Ltd., Japan). The sample for measuring compressive strength was cylindrical and had the width of 50 mm and the length of 50 mm.

(52) When compressive strength was measured, the adapter had the diameter of 10 mm, the entrance (admission) distance was 0.15 mm, and maximum stress of the load cell was 10 kg (maximum 20 kg).

(53) TABLE-US-00001 TABLE 1 Example Example Example Example Comparative Classification 1 2 3 4 Example 1 Hydrogel absorbancy 240 220 190 170 120 Stability 60 minutes 5 hours 10 hours X 24 hours X Strength (kg/cm.sup.2) 6.4 5.3 5.4 5.1 1.0

(54) As shown in Table 1, it was confirmed that Examples 1 to 4 of the present invention had excellent absorbancy, stability (fluidization of the gel), and strength. On the other hand, absorbancy, stability, and strength of Comparative Example 1 were not excellent as compared to Examples 1 to 4.

(55) FIG. 2 shows stability of the hydrogel manufactured according to Example 1 and Comparative Example 1, and it could be confirmed that the gel was not fluidized but stable properties were maintained even after 24 hours in Example 1 but the gel was fluidized after 24 hours in Comparative Example 1.