CN110613630B - Sunscreen cream containing benzophenone derivative nanocrystals and preparation method thereof - Google Patents

Abstract

The invention relates to a sunscreen cream containing benzophenone derivative nanocrystals, wherein the benzophenone derivative nanocrystals are dispersed in a water phase to form a benzophenone derivative nanocrystal suspension, and then are emulsified with an oil phase; the benzophenone derivatives include oxybenzophenones and dihydroxybenzophenones. The benzophenone derivative nano-crystal suspension is prepared into the nano-crystal suspension, the accumulation of crystals enables molecules in the suspension to be different from the molecular environment in a solution, so that the gradual process in an energy dissipation cycle is faster than the speed in the solution, the ultraviolet absorption efficiency of the benzophenone derivative nano-crystal suspension is better, and the benzophenone derivative nano-crystal suspension has better sun-screening performance, efficiency and stability when being added into a sun-screening cream.

Description

Sunscreen cream containing benzophenone derivative nanocrystals and preparation method thereof

Technical Field

The invention belongs to the technical field of daily chemical industry, and particularly relates to sunscreen cream containing benzophenone derivative nanocrystals and a preparation method thereof.

Background

Benzophenone and derivatives thereof are aryl ketone compounds with very many functions and have strong absorption effect on ultraviolet light. Among them, hydroxybenzophenone (OB) and Dihydroxybenzophenone (DOB) are very common sunscreen agents used in cosmetics, and have good absorption of ultraviolet rays. According to literature reports, the sunscreen effect of OB and DOB can be explained microscopically. They absorb energy of ultraviolet rays and are excited to an excited state, and then go back to a ground state through a series of processes to complete a cycle process.

At present, the application of benzophenone derivatives as ultraviolet absorbers in the cosmetic industry is still a more traditional method, namely, the benzophenone derivatives and other oil phase components are dissolved in a hydrophobic solvent such as glycerin, and then the benzophenone derivatives and other oil phase components are uniformly mixed with a water phase component and an emulsifier to prepare the sunscreen cream. However, the conventional sunscreen agents are mainly used by directly dissolving the benzophenone derivative in the emulsion, which is said to be dissolved in the solution. And the dynamics fitting research of the femtosecond transient spectrum shows that the benzophenone derivative can complete the energy dissipation process more slowly in the solution phase.

Disclosure of Invention

The invention aims to provide a nanometer crystal containing benzophenone derivatives, which is added into sunscreen cream as a formula to improve the sunscreen performance and efficiency, and has a wide application prospect in the field of cosmetics.

A sunscreen cream comprising benzophenone derivative nanocrystals dispersed in an aqueous phase to form a suspension of benzophenone derivative nanocrystals, which is then emulsified with an oil phase.

According to the invention, OB and DOB spontaneously form nanoscale crystals after being dispersed in water. The accumulation of crystals causes the molecules in the crystals to be different from the molecular environment in the solution, so that the gradual process in the energy dissipation cycle is faster than the speed in the solution, and therefore, the efficiency of the OB and the DOB completing the energy dissipation cycle in the solution is greatly different from that of the nanocrystal.

Preferably, the benzophenone derivatives include hydroxybenzophenones and dihydroxybenzophenones.

Preferably, the composition comprises the following components in percentage by weight:

preferably, the composition comprises the following components in percentage by weight:

preferably, the preparation of the benzophenone derivative nanocrystal suspension mainly comprises: under the oscillation of an ultrasonic cleaner, slowly injecting saturated benzophenone derivative acetone concentrated solution into distilled water, carrying out ultrasonic treatment for 10-30min, and introducing nitrogen to blow away residual organic solvent to obtain clear colorless benzophenone derivative nanocrystal suspension.

The preparation method of the sunscreen cream containing the benzophenone derivative nanocrystal mainly comprises the following steps:

(1) preparing a benzophenone derivative nanocrystal suspension;

(2) mixing the benzophenone derivative nanocrystal suspension with the rest of water phase materials to obtain a water phase;

(3) preparing an oil phase;

(4) and (3) mixing the water phase obtained in the step (2), the oil phase obtained in the step (3) and an emulsifier, and emulsifying.

Compared with the prior art, the benzophenone derivative nano-crystal suspension is prepared into the nano-crystal suspension, the accumulation of the crystals enables molecules in the suspension to have different environments from molecules in a solution, so that the gradual process in an energy dissipation cycle is faster than the speed in the solution, the ultraviolet absorption efficiency of the benzophenone derivative nano-crystal suspension is better, and the benzophenone derivative nano-crystal suspension has better sun-screening performance, efficiency and stability when being added into a sun-screening cream.

Drawings

Fig. 1 is a process flow diagram for preparing sunscreen cream containing nano crystals of benzophenone derivative according to the present invention;

FIG. 2 is a graph showing the distribution of particle size of oxybenzone OB nanocrystals of the present invention;

FIG. 3 is a graph of the particle size distribution of dihydroxybenzophenone DOB nanocrystals of the present invention;

FIG. 4 is a graph of the UV-visible absorption vs. time trend of the nano-crystalline suspensions of oxybenzophenone OB and dihydroxybenzophenone DOB of the present invention; (a) is hydroxybenzophenone OB, (b) is dihydroxybenzophenone DOB;

FIG. 5 is a comparison of femtosecond transient absorption kinetic fits of hydroxybenzophenone OB and dihydroxybenzophenone DOB of the present invention in solution and a nanocrystal suspension; (a) is hydroxybenzophenone OB, (b) is dihydroxybenzophenone DOB;

FIG. 6 is a comparison XRD of single crystals and nanocrystals of hydroxybenzophenone OB and dihydroxybenzophenone DOB of the present invention; (a) is hydroxybenzophenone OB, (b) is dihydroxybenzophenone DOB;

FIG. 7 is a graph showing UV absorption spectra of a suspension of nanocrystals of oxybenzophenone OB and dihydroxybenzophenone DOB of the present invention in acetonitrile solution, acetonitrile/water at a ratio of 1:1, respectively; (a) is hydroxybenzophenone OB, and (b) is dihydroxybenzophenone DOB.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.

Example 1

Hydroxybenzophenone OB nanocrystal suspensions

The preparation of OB nanocrystals, consisting essentially of: under the shaking of an ultrasonic cleaner (the temperature is 20 ℃, the power is 100W), 10 mu l of 5mg/ml OB acetone concentrated solution is slowly injected into 10ml of distilled water, ultrasonic treatment is carried out for 20min, and nitrogen is introduced for 5min to blow away the residual organic solvent, so that clear colorless nanocrystal suspension is obtained.

Characterization of OB nanocrystals: the particle size of OB can be detected by dynamic light scattering. The mean particle size of the nanocrystals in suspension obtained using a Malvern Zetasizer Nano ZS90 nanoparticle radius and potential analyzer is shown in Table 1 and the particle size distribution is shown in FIG. 2. It is evident that the average size of the nanocrystals is 250nm, the distribution is approximately between 100 and 400, and the size of the particle size conforms to the definition of the nanocrystals.

TABLE 1 average particle size of OB nanocrystals

	Temperature (. degree.C.)	Scattering angle (°)	Average particle size (nm)
				1	25	90	270.9
2	25	90	243.7
				3	25	90	235.9

And (3) detecting the stability of the OB nanocrystals: and measuring the ultraviolet-visible spectrum of the prepared nanocrystal suspension every 5min to obtain the ultraviolet-visible absorption change within 45 min. As shown in FIG. 4, the ultraviolet-visible absorption peak of the OB nanocrystal suspension is almost unchanged within 45min (the nanocrystals can cause the ultraviolet-visible absorption to be reduced when being aggregated and settled), which indicates that the nanocrystals of the molecule can be kept stable for a long time without aggregation and settlement, and have better stability.

The OB of nanocrystals is most characterized by a faster rate of energy absorption and dissipation than OB in solution phase, as can be seen from their microscopic processes. The femtosecond transient spectrum can be used for realizing the detection of the two microscopic processes, and the service life of the ultrafast processes can be seen by performing dynamic fitting on the result. It is evident from fig. 5 that the lifetime of each process is smaller in the nanocrystal, i.e. it completes each process at a greater rate than the solution phase, and thus OB in the nanocrystal completes the process of energy dissipation faster and therefore more efficiently. Thus, the OB of the nanocrystals has better sunscreen effect than OB in the solution phase.

Example 2

Dioxybenzophenone (DOB) nanocrystal suspensions

The preparation of DOB nanocrystals mainly comprises the following steps: slowly injecting 10 mu l of DOB acetone concentrated solution with the concentration of 5mg/ml into 10ml of distilled water under the shaking of an ultrasonic cleaner (the temperature is 20 ℃, the power is 100W at the temperature), carrying out ultrasonic treatment for 20min, and introducing nitrogen for 5min to blow away the residual organic solvent, thereby obtaining a clear and colorless nanocrystal suspension.

Characterization of DOB nanocrystals: the particle size of the DOB can be detected by dynamic light scattering. The mean particle size of the nanocrystals in suspension obtained using a Malvern Zetasizer Nano ZS90 nanoparticle radius and potential analyzer is shown in Table 2 and the particle size distribution is shown in FIG. 3. It is obvious that the average particle size of the nanocrystal is 195nm, the distribution is approximately between 100-400, and the size of the particle size accords with the definition of the nanocrystal.

TABLE 2 average particle size of DOB nanocrystals

	Temperature of	Scattering angle (°)	AverageParticle size (nm)
				1	25	90	193.9
2	25	90	188.8
				3	25	90	207

Detecting the stability of the DOB nanocrystals: and measuring the ultraviolet-visible spectrum of the prepared nanocrystal suspension every 5min to obtain the ultraviolet-visible absorption change within 45 min. As shown in FIG. 4, the UV-visible absorption peak of the nanocrystal suspension of DOB is almost unchanged within 45min (the nanocrystals can cause the UV-visible absorption to be reduced when being aggregated and settled), which indicates that the nanocrystals of the molecule can be kept stable for a long time without aggregation and settlement, and have better stability.

The biggest characteristic of DOB in nanocrystals is the faster rate of energy absorption and dissipation compared to DOB in solution phase, which can be reflected from their microscopic processes. The femtosecond transient spectrum can be used for realizing the detection of the two microscopic processes, and the service life of the ultrafast processes can be seen by performing dynamic fitting on the result. It is evident from fig. 5 that the first four lifetimes of the nanocrystals are comparable to solution, but the fifth lifetime is smaller in the nanocrystal, i.e., it completes the entire excited state deactivation process at a greater rate than the solution phase, and therefore the energy dissipation process is completed more quickly at the DOB of the nanocrystal, which is more efficient. Thus the nanocrystalline DOB has a better sunscreen effect than does in the solution phase.

Example 3

A sunscreen cream containing benzophenone derivative nanocrystals has the components and the content shown in Table 3.

Table 3 components and contents of sunscreen cream containing benzophenone derivative nanocrystals

DI WATER-DIFFERED WATER	Allowance of
		Hydroxyethyl cellulose (2%)	30
Glycerol	6
		Hydroxy phenyl methyl ester	0.2
Propyl hydroxybenzoate	0.1
		Bis (hydroxymethyl) imidazolidinyl urea	0.2
Allantoin Allantoin	0.1
		Caprylic/capric triglyceride GTCC	4
Tristearin-PEG-100 stearate	3
		Hexadecanol and octadecanol	3
DC345 cyclomethicone oil	4
		Titanium dioxide KM1204	2
ISP557, ethylhexyl methoxycinnamate	7.5
		Parsol5000, 4-methylbenzylidene camphor	2.5
Parsol1789, butyl methoxydibenzoylmethane	2.5
		Benzophenone derivative nanocrystals	2.5
VE	0.4
		EDTA-Na2	0.05
Bisabolol	0.2
		Essence	0.3
Phenoxyethanol	0.2

The preparation method mainly comprises the following steps:

(1) preparing a benzophenone derivative nanocrystal suspension;

(2) mixing the benzophenone derivative nanocrystal suspension with the rest of water phase mixture to obtain a water phase;

(3) preparing an oil phase;

(4) and (3) mixing the water phase obtained in the step (2), the oil phase obtained in the step (3) and an emulsifier, and emulsifying.

Comparative example 1

The benzophenone derivative nanocrystal in example 3 was replaced with a saturated benzophenone derivative solution, and the other components and the contents thereof were the same. The preparation method comprises dissolving saturated solution of benzophenone derivative and other oil phase components in glycerol, and mixing with water phase component and emulsifier to obtain sunscreen cream.

Sunscreen Performance test

The sunscreen cream prepared in example 3 and comparative example 1, and a commercial sunscreen product senegal are subjected to an effect test for preventing sunshine:

60 volunteer subjects are randomly divided into three groups, 20 persons in each group are respectively smeared with the sunscreen cream prepared in the example 3 and the sunscreen product sold in the comparative example 1, the sunscreen cream and the sunscreen product sold in the sengto are used for fast sun protection, the sunscreen cream and the sunscreen product are smeared on the face and the naked part of the body once a day after the face is cleaned in the morning, and the sunscreen cream and the sunscreen product are continuously smeared for 30 days. The sunscreen effect and the sensation of use were then scored and averaged, with the results shown in table 4. Note: the sun-screening effect is divided into 5 points, and 5 points are the highest points, which shows that the sun-screening effect is good and very satisfactory; 4, the sun protection is better; 3, well sun-proof; the sunscreen effect was very poor when the score was 3 or less. The using feeling comprises whether the product is greasy or not, whether the product is uniformly coated or not and the like, wherein the total score is 5, and the score of 5 is the highest score, which means that the product is not greasy and is uniformly coated and is very satisfactory; 4, the use feeling is better; 3 points are good in use feeling, and less than 3 points are very greasy and uneven in application.

Table 4 grading test of sunscreen, commercial sunscreen zishengan sunscreen of example 3 and comparative example 1

	Sunscreen of example 3	Sunscreen of comparative example 1	The senior hall is fast to the sun
				Sunscreen effect	4.5	3.6	4.8
Feeling of use	4.2	4.0	4.6

Claims (6)

1. A sunscreen cream comprising benzophenone derivative nanocrystals, wherein the benzophenone derivative nanocrystals are dispersed in an aqueous phase to form a benzophenone derivative nanocrystal suspension, which is then emulsified with an oil phase.

2. The sunscreen cream containing nanocrystals of benzophenone derivatives according to claim 1 wherein said benzophenone derivatives comprise oxybenzophenones and dihydroxybenzophenones.

3. The sunscreen cream containing the nano-crystals of the benzophenone derivative according to claim 1 is characterized by comprising the following components in percentage by weight:

4. the sunscreen cream containing the nano-crystals of the benzophenone derivative according to claim 1 is characterized by comprising the following components in percentage by weight:

5. the sunscreen cream containing benzophenone derivative nanocrystals according to claim 1, wherein the suspension of benzophenone derivative nanocrystals is prepared by a method comprising essentially of: under the oscillation of an ultrasonic cleaner, slowly injecting saturated benzophenone derivative acetone concentrated solution into distilled water, carrying out ultrasonic treatment for 10-30min, and introducing nitrogen to blow away residual organic solvent to obtain clear colorless benzophenone derivative nanocrystal suspension.

6. The method for preparing sunscreen cream containing nano crystals of benzophenone derivative according to claim 1, which mainly comprises the following steps:

(1) preparing a benzophenone derivative nanocrystal suspension;

(2) mixing the benzophenone derivative nanocrystal suspension with the rest of water phase mixture to obtain a water phase;

(3) preparing an oil phase;

(4) and (3) mixing the water phase obtained in the step (2), the oil phase obtained in the step (3) and an emulsifier, and emulsifying.

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