A kind of preparation method of dimethicone cream

Abstract

The present invention relates to a preparation method of a dimethicone cream, comprising the following steps: step 1, adding carbomer to purified water, freezing at 20°C, stirring, until carbomer is completely dissolved, and obtaining a carbomer transparent gel; step 2, mixing dimethicone, white vaseline and carbomer transparent gel and stirring evenly to obtain a pre-emulsified gel system; step 3, adding sorbic acid and purified water to stearic acid polyoxyethylene (40) ester, heating to dissolve, and obtaining an aqueous phase; step 4, adding the aqueous phase to the pre-emulsified gel system, stirring evenly to obtain a secondary emulsified paste; step 5, grinding the secondary emulsified paste in a colloid mill to obtain a dimethicone crude cream; step 6, sending the dimethicone crude cream into a homogenizer, high-speed homogenization, and obtaining a dimethicone cream. The product of the present invention is oily, smooth, and has a small particle size; and the product quality is stable.

Description

Technical Field

[0001] The invention relates to the technical field of pharmaceutical preparations, and in particular to a method for preparing a dimethicone cream. Background Art

[0002] Dimethicone, also known as methyl silicone oil and polydimethylsiloxane liquid, is a low molecular weight liquid polyoxysilane structure, a colorless, tasteless, odorless, non-toxic oily liquid; the molecular formula is CH3[Si(cH3)2]nSi(CH3)3, and is widely used in insulation, heat-resistant, moisture-proof fillers, high-efficiency defoaming agents, release agents, lubricants and surface treatment agents. Dimethicone made into emulsion or cream and applied to human skin has a lubricating effect, is non-irritating, and is easy to spread.

[0003] In pharmacy, different dosage forms are suitable for different methods of administration. Compared with emulsions, gels, and solutions, creams are more suitable for smooth, hairless skin, diffuse, hyperkeratotic symptoms, and use on the palms, soles, and other parts of the body. Creams are divided into oil-in-water (O / W) type and water-in-oil (W / O) type. Dimethicone cream is an oil-in-water cream. When dimethicone cream is used alone on the skin, it is a multifunctional cream that combines skin care and beauty. At the same time, dimethicone is also commonly used to treat symptoms such as chapped skin, eczema, and senile pruritus.

[0004] Dimethicone cream is a hospital preparation product included in the "Beijing Medical Institution Preparation Regulations" published in 2014. At present, most of the products produced by the existing preparation methods of dimethicone cream have problems such as rough properties, poor stability, and not conducive to transdermal absorption.

[0005] Therefore, a method for preparing a dimethicone cream is now proposed, which can make the prepared dimethicone cream product have good properties, stable quality, is conducive to transdermal absorption, and has a simple component composition. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for preparing a dimethicone cream, which can make the prepared dimethicone cream product have good properties, stable quality, is conducive to transdermal absorption, and has a simple component composition.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] A method for preparing a dimethicone cream, wherein the raw materials for preparing the dimethicone cream include: 100 parts of dimethicone, 20 parts of white vaseline, 5 parts of carbomer, 100 parts of polyoxyl (40) stearate, 1 part of sorbic acid, and 274 parts of purified water;

[0009] The preparation method of the dimethicone cream comprises the following steps:

[0010] a. Add 5 parts of carbomer to 50 parts of purified water, freeze at -20°C, and stir every 6 minutes until the carbomer is completely dissolved to obtain a carbomer transparent gel;

[0011] b. Mix 100 parts of dimethicone, 20 parts of white vaseline and carbomer transparent gel and stir evenly to obtain a pre-emulsified gel system;

[0012] c. Add 1 part of sorbic acid and 224 parts of purified water to 100 parts of polyoxyl (40) stearate, heat to 100° C.-120° C. to dissolve, and obtain an aqueous phase;

[0013] d. Add the aqueous phase to the pre-emulsified gel system and stir evenly to obtain a secondary emulsified paste;

[0014] e. Grinding the secondary emulsified paste in a colloid mill to obtain a crude dimethicone cream;

[0015] f. Send the crude dimethicone cream into a homogenizer and homogenize at a high speed of 8000-12000 rpm to obtain a dimethicone cream.

[0016] The main chain of dimethicone molecule is based on Si-O-Si bond, and the side chain is -CH3. The side group has little steric hindrance, and the molecular chain can rotate almost freely. At the same time, the interaction between -CH3 and -CH3 is weak, which makes the intermolecular force of silicone oil weak. The special structure of this molecular composition makes it highly physically and chemically inert, safer during use, easy to apply, and will not cause pores to be clogged or stain clothing.

[0017] Carbomer, also known as carbonyl ethylene copolymer or carbopol, is a high molecular weight polymer obtained by cross-linking polyalkyl sucrose or polyalkyl pentaerythritol with acrylic acid. It is a white loose powder and is often used as an excipient in topical gels. Carbomer has a strong hydrophilicity. The dry powder of carbomer has a very strong hygroscopicity. When it is directly put into water or other polar solvents, it is easy to form a mass or incomplete wetting.

[0018] Furthermore, the viscosity of the dimethicone oil is 1000cs-1500cs.

[0019] The molecular formula of dimethicone is CH3[Si(cH3)2]nSi(CH3)3, with an average molecular weight of 5000 to 100000. Depending on the molecular weight, the kinematic viscosity ranges from 1.0×10-6 to 100000×10-6 square meters / second.

[0020] Furthermore, in the step f, the homogenization time is 10-20 minutes to obtain a dimethicone cream with reduced viscosity.

[0021] Furthermore, the grinding time in step e is 0.5-1 hour. The colloid mill has the effects of dispersing, emulsifying and homogenizing the paste.

[0022] Sorbic acid is a highly effective and safe preservative recommended by the Food and Agriculture Organization and the World Health Organization. It is widely used in food, beverage, tobacco, pesticide, cosmetics and other industries. Since sorbic acid contains carbonyl and conjugated double bonds in its molecular structure, the carbonyl group increases the acidity of sorbic acid and inhibits the growth of microorganisms. The conjugated double bonds can combine with the sulfhydryl groups of microbial enzymes, thereby destroying the enzyme system structure, making the enzyme inactive, and ultimately inhibiting the reproduction of microorganisms to achieve the effect of preservation.

[0023] Preferably, the mixing and stirring speed in step b is 600 rpm, and the mixing and stirring time is 0.5-1 hour.

[0024] In a specific embodiment of the present scheme, the step a is specifically as follows: slowly and evenly add 5 parts of carbomer to 50 parts of purified water, stir and put into a refrigerator to freeze, take out and stir once every 6 minutes, the freezing temperature is -20°C, and after freezing for 30 minutes, a carbomer transparent gel is obtained.

[0025] Stearic acid polyoxyl (40) ester is a non-ionic surfactant, which is not in an ionic state in the solution, has high stability, is not easily affected by strong electrolyte inorganic salts, and is not easily affected by acids and alkalis. It also has good compatibility with other types of surfactants.

[0026] Dimethicone and white vaseline are oil phase substances, and carbomer transparent gel is mixed with dimethicone and white vaseline to form a pre-emulsified gel system. In this process, carbomer has the dual functions of thickener and emulsifier. During the mixing process, it can be observed that the oily substance emulsifies and disappears, and the viscosity of the mixture increases, thereby obtaining a pre-emulsified gel system. The pre-emulsified gel system is mixed with the aqueous phase, and further emulsified with polyoxyl (40) stearate to obtain a secondary emulsified paste. The secondary emulsified paste is ground with a colloid mill to obtain a dimethicone crude cream. After secondary emulsification and grinding, the viscosity of the dimethicone crude cream is lower than that of the pre-emulsified gel system, but its viscosity is still higher than that of an ointment product. A homogenizer is used to homogenize the dimethicone crude cream to reduce the viscosity, thereby obtaining an ointment product with suitable viscosity.

[0027] The beneficial effects of the present invention are:

[0028] (1) In this scheme, dimethicone, white vaseline, and carbomer transparent gel are first mixed and emulsified to obtain a pre-emulsified gel system, which is then mixed with an aqueous phase prepared from polyoxyl (40) stearate, sorbic acid, and purified water, and finally ground and homogenized to prepare a stable dimethicone cream, that is, dimethicone, white vaseline, and carbomer gel are first preliminarily emulsified to form a pre-emulsified gel system, which is then secondary emulsified with polyoxyl (40) stearate to obtain a cream product with a relatively complex emulsified state, and finally the viscosity is adjusted by mechanical force to obtain a cream product with reliable quality, stable chemical properties, and a particle size of 2-3 μm;

[0029] (2) Carbomer and polyoxyl (40) stearate have good compatibility, and the combination of the two can ensure that the cream after high-speed shearing has suitable viscosity and good stability. It can also remain stable for 3 months at a temperature of 30°C ± 2°C and a relative humidity of 60% ± 5%, without "emulsification" and without changes in particle size. Therefore, this solution can prepare a dimethicone cream product with good product properties, stable quality and good transdermal absorption.

[0030] (3) The formula ingredients of this scheme are relatively simple, and the raw materials used are relatively safe, which is conducive to avoiding the occurrence of allergic symptoms; and the dimethicone cream prepared by this scheme is an acidic cream, which is suitable for use on human skin. The addition of sorbic acid as an antibacterial agent is safe and reliable, and the antibacterial effect of sorbic acid in the acidic cream is enhanced. Therefore, the dimethicone cream prepared by this scheme has a good antibacterial effect, is suitable for skin use, and can be stably stored for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the dimethicone cream prepared in Example 1;

[0032] Figure 2 Schematic diagram of the dimethicone cream prepared in Example 2;

[0033] Figure 3 Schematic diagram of the dimethicone cream prepared in Example 3;

[0034] Figure 4 Schematic diagram of the dimethicone cream prepared in Comparative Example 1;

[0035] Figure 5 Schematic diagram of the dimethicone cream prepared in Comparative Example 2;

[0036] Figure 6 This is a schematic diagram of Example 1 after being placed for 3 months;

[0037] Figure 7 This is a schematic diagram of Example 2 after being placed for 3 months;

[0038] Figure 8 This is a schematic diagram of Example 3 after being placed for 3 months;

[0039] Fig. 9 This is a schematic diagram of Comparative Example 1 after being placed for 3 months;

[0040] Fig.10 This is a schematic diagram of Comparative Example 2 after being placed for 3 months. DETAILED DESCRIPTION

[0041] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments, but the protection scope of the present invention is not limited to the following.

[0042] Example 1

[0043] A method for preparing a dimethicone cream comprises the following steps:

[0044] (1) Add 5 g of carbomer to 50 g of purified water, stir, and then put into a refrigerator for freezing. Take it out and stir it every 6 minutes until the carbomer is completely dissolved to obtain a carbomer transparent gel;

[0045] (2) 100 g of dimethicone, 20 g of white vaseline and carbomer transparent gel were mixed and stirred for 0.5 hour at a stirring speed of 600 min / rev until the pre-emulsified system was obtained;

[0046] (3) adding 1 g of sorbic acid and 224 g of purified water to 100 g of polyoxyl (40) stearate, and then heating to 100° C. to dissolve, thereby obtaining an aqueous phase;

[0047] (4) slowly adding the aqueous phase into the pre-emulsified gel system and stirring evenly to obtain a secondary emulsified paste;

[0048] (5) grinding the secondary emulsified paste in a colloid mill, and grinding for 0.5 hours using the shear force of the colloid mill to form a crude dimethicone cream;

[0049] (6) The crude dimethicone cream was homogenized in a homogenizer at high speed, 8000 rpm, for 10 minutes to obtain a dimethicone cream.

[0050] Among them, the viscosity of dimethicone is 1000cs.

[0051] Furthermore, step (1) is specifically as follows: slowly and evenly add 5 g of carbomer to 50 g of purified water, stir and then put into a refrigerator for freezing, take out and stir once every 6 minutes, the freezing temperature is -20°C, and after freezing for 30 minutes, a carbomer transparent gel is obtained.

[0052] The dimethicone cream obtained in this example performs as follows Figure 1As shown, the pH was detected to be 5.

[0053] Example 2

[0054] A method for preparing a dimethicone cream comprises the following steps:

[0055] (1) Add 5 g of carbomer to 50 g of purified water, stir, and then put into a refrigerator for freezing. Take it out and stir it every 6 minutes until the carbomer is completely dissolved to obtain a carbomer transparent gel;

[0056] (2) 100 g of dimethicone, 20 g of white vaseline and carbomer transparent gel were mixed and stirred for 40 minutes at a stirring speed of 600 min / rev until the pre-emulsified system was obtained;

[0057] (3) adding 1 g of sorbic acid and 224 g of purified water to 100 g of polyoxyl (40) stearate, and then heating to 110° C. to dissolve the mixture to obtain an aqueous phase;

[0058] (4) slowly adding the aqueous phase into the pre-emulsified gel system and stirring evenly to obtain a secondary emulsified paste;

[0059] (5) grinding the secondary emulsified paste in a colloid mill for 40 minutes using the shear force of the colloid mill to allow the aqueous phase to merge with the pre-emulsified gel system to form a crude dimethicone cream;

[0060] (6) The crude dimethicone cream was homogenized in a homogenizer at high speed, 10,000 rpm, for 15 minutes to obtain Figure 2 Simethicone cream as shown.

[0061] Among them, the viscosity of dimethicone is 1000cs.

[0062] Furthermore, step (1) is specifically as follows: slowly and evenly sprinkle 5 g of carbomer into 50 g of purified water, stir and put into a refrigerator for freezing, take out and stir once every 6 minutes, the freezing temperature is -20°C, and after freezing for 30 minutes, a carbomer transparent gel is obtained.

[0063] Example 3

[0064] A method for preparing a dimethicone cream comprises the following steps:

[0065] (1) Add 5 g of carbomer to 50 g of purified water, stir, and then put into a refrigerator for freezing. Take it out and stir it every 6 minutes until the carbomer is completely dissolved to obtain a carbomer transparent gel;

[0066] (2) 100 g of dimethicone, 20 g of white vaseline and carbomer transparent gel were mixed and stirred for 50 minutes at a stirring speed of 600 min / rev until the pre-emulsified system was obtained;

[0067] (3) adding 1 g of sorbic acid and 224 g of purified water to 100 g of polyoxyl (40) stearate, and then heating to 120° C. to dissolve the mixture to obtain an aqueous phase;

[0068] (4) slowly adding the aqueous phase into the pre-emulsified gel system and stirring evenly to obtain a secondary emulsified paste;

[0069] (5) grinding the secondary emulsified paste in a colloid mill for 50 minutes using the shear force of the colloid mill to allow the aqueous phase to merge with the pre-emulsified gel system to form a crude dimethicone cream;

[0070] (6) The crude dimethicone cream was homogenized in a homogenizer at high speed, 12000 rpm, for 20 minutes to obtain Figure 3 Simethicone cream as shown.

[0071] Among them, the viscosity of dimethicone is 1500cs.

[0072] Furthermore, step (1) is specifically as follows: slowly and evenly sprinkle 5 g of carbomer into 50 g of purified water, stir and put into a refrigerator for freezing, take out and stir once every 6 minutes, the freezing temperature is -20°C, and after freezing for 30 minutes, a carbomer transparent gel is obtained.

[0073] Comparative Example 1

[0074] The product composition and the process flow of the preparation method in this comparative example are the same as those in Example 1, except that the process parameters of this comparative example are the same as those of the existing dimethicone cream preparation method, and no homogenizer is used for homogenization.

[0075] (1) Add 5 g of carbomer to 50 g of purified water, stir and freeze in a -20°C refrigerator, take out and stir every 6 minutes, and after 30 minutes, the carbomer is completely dissolved to obtain a carbomer transparent gel;

[0076] (2) 100 g of 1000 cs dimethicone, 20 g of white vaseline and carbomer transparent gel were mixed and stirred for 50 minutes at a stirring speed of 600 min / rev until the pre-emulsified system was obtained;

[0077] (3) adding 1 g of sorbic acid and 224 g of purified water to 100 g of polyoxyl (40) stearate, and then heating to 70° C. to dissolve the mixture to obtain an aqueous phase;

[0078] (4) slowly adding the aqueous phase into the pre-emulsified gel system and stirring evenly to obtain a secondary emulsified paste;

[0079] (5) The secondary emulsified paste is put into a colloid mill for grinding. The shear force of the colloid mill is used for grinding for 30 minutes to allow the water phase to merge with the pre-emulsified gel system to obtain Figure 4 Simethicone cream as shown.

[0080] Comparative Example 2

[0081] The product composition of this comparative example is the same as that of the existing dimethicone cream preparation method, as shown in Table 1, and the preparation method of this comparative example is the same as that of Example 1.

[0082] (1) 1000 cs of dimethicone was mixed with stearic acid, lanolin and white vaseline and stirred for 50 minutes at a stirring speed of 600 min / rev to form an oil phase;

[0083] (2) Add an appropriate amount of purified water to 200 ml of ethylparaben, triethanolamine, and glycerol, heat to 100°C, dissolve and stir to form an aqueous phase;

[0084] (3) slowly adding the water phase to the oil phase, putting it into a colloid mill for grinding, and using the shear force of the colloid mill to grind for 30 minutes to merge the water phase and the oil phase to form a crude dimethicone cream;

[0085] (4) The crude dimethicone cream was homogenized in a homogenizer at high speed at 8000 rpm for 10 minutes to prepare a Figure 5 Simethicone cream as shown.

[0086] Table 1 Product composition

[0087] materials Dimethicone Stearic acid Lanolin White Vaseline Ethylparaben Triethanolamine glycerin Purified water Dosage(g) 100g 74.5g 10g 35g 0.5g 10g 20g 250g

[0088] Experimental example

[0089] Comparison of test results of dimethicone cream products:

[0090] 1. Take samples of the dimethicone creams prepared in Example 1, Example 2, Example 3, Comparative Example 1, and Comparative Example 2, respectively, smear, and observe the particle size of the prepared products under a microscope:

[0091] (1) The product prepared in Example 1 is oily and smooth; the particle size observed under a microscope is generally 1 μm, and the largest is 2-4 μm;

[0092] (2) The product prepared in Example 2 is oily and smooth; the particle size observed under a microscope is generally 1 μm, and the largest is 2-3 μm;

[0093] (3) The product prepared in Example 3 is oily and smooth; the particle size observed under a microscope is generally 1 μm, and the largest is 2-3 μm;

[0094] (4) The product prepared in Comparative Example 1 has uneven properties, particles, and incomplete emulsification; the particle size observed under a microscope is generally 30-35 μm, and the largest is 40-50 μm;

[0095] (5) The product prepared in Comparative Example 2 has a fine texture and incomplete emulsification. The particle size observed under a microscope is generally 3-4 μm, and the largest is 5-7 μm.

[0096] 2. Place the products prepared in Example 1, Example 2, Example 3 and the products prepared in Comparative Example 1 and Comparative Example 2 in a constant temperature and humidity chamber: at a temperature of 30°C ± 2°C and a relative humidity of 60% ± 5%. After 3 months, observe the product properties and particle size under a microscope:

[0097] (1) The properties of the product prepared in Example 1 remain unchanged: smooth and tender (such as Figure 6 As shown); under the microscope, the particle size is generally 1μm, and the largest is 2-4μm;

[0098] (2) The properties of the product prepared in Example 2 remained unchanged: smooth and smooth (such as Figure 7 The particle size observed under a microscope is generally 1 μm, which is 2-3 μm.

[0099] (3) The properties of the product prepared in Example 3 remain unchanged: smooth and tender (such as Figure 8 As shown); under the microscope, the particle size is generally 1μm, and the largest is 2-3μm;

[0100] (4) Product properties of Comparative Example 1: The appearance of the paste is completely stratified, with obvious coarse particles (such as Fig. 9 The particle size observed under a microscope is generally 40-50μm, and the largest is 55-60μm;

[0101] (5) Product properties of Comparative Example 2: The appearance of the paste is completely stratified, and the fineness is slightly changed (such as Fig.10 The particle size observed under a microscope is generally 5-7 μm, and the largest is 8-10 μm.

[0102] Conclusion: It can be seen from the experimental examples that the products prepared in Examples 1, 2 and 3 of the present invention are oily and smooth, and have a smaller particle size than that of the product prepared in the comparative example, which is conducive to transdermal absorption; after being placed in a constant temperature and humidity drying oven for 3 months, there is no "demulsification" change of separation of oil phase components and water phase components, and the particle size does not change, indicating that the product formula proposed in the present invention is prepared by the method of the present invention, and the dimethicone cream product has stable quality and good properties.

[0103] The reason for the demulsification and stratification in Comparative Example 1 may be that the sorbic acid was not completely dissolved, the materials were not mixed evenly, and the viscosity was not adjusted by homogenization, resulting in larger particles and poor properties of the subsequent product, which was easy to stratify and demulsify after long storage.

[0104] In the present invention, the carbomer adopts the pharmaceutical excipient carbomer B type.

[0105] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for preparing a dimethicone cream, characterized in that: The raw materials for preparing the dimethicone cream include: by weight, 100 parts of dimethicone, 20 parts of white vaseline, 5 parts of carbomer, 100 parts of polyoxyl (40) stearate, 1 part of sorbic acid, and 274 parts of purified water; The preparation method of the dimethicone cream comprises the following steps: a. Add 5 parts of carbomer to 50 parts of purified water, freeze at -20°C, and stir every 6 minutes until the carbomer is completely dissolved to obtain a carbomer transparent gel; b. Mix 100 parts of dimethicone, 20 parts of white vaseline and carbomer transparent gel and stir evenly to obtain a pre-emulsified gel system; c. Add 1 part of sorbic acid and 224 parts of purified water to 100 parts of polyoxyl (40) stearate, heat to 100°C-120°C to dissolve, and obtain an aqueous phase; d. Add the aqueous phase to the pre-emulsified gel system and stir evenly to obtain a secondary emulsified paste; e. Grinding the secondary emulsified paste in a colloid mill to obtain a crude dimethicone cream; f. Send the crude dimethicone cream into a homogenizer and homogenize at a high speed of 8000-12000 rpm to obtain a dimethicone cream; The viscosity of the dimethicone oil is 1000cs-1500cs.

2. A method for preparing a dimethicone cream according to claim 1, characterized in that: In the step f, the homogenization time is 10-20 minutes to obtain a dimethicone cream with reduced viscosity.

3. A method for preparing a dimethicone cream according to claim 2, characterized in that: The grinding time in step e is 0.5-1 hour.

4. A method for preparing a dimethicone cream according to claim 3, characterized in that: The mixing speed in step b is 600 rpm, and the mixing time is 0.5-1 hour.

5. A method for preparing a dimethicone cream according to claim 4, characterized in that: The step a is specifically as follows: 5 parts of carbomer are slowly and evenly added to 50 parts of purified water, and then put into a refrigerator for freezing after stirring, and taken out and stirred once every 6 minutes, the freezing temperature is -20°C, and the carbomer transparent gel is obtained after freezing for 30 minutes.

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