CN-122005353-A - Oil-in-water microsphere for wrapping cosmetic active

Abstract

The invention discloses an oil-in-water (o/w) microsphere for wrapping cosmetic active substances, wherein in the microsphere, a water phase forms a shell layer to wrap an inner oil phase, the core composition of the inner oil phase comprises oil-soluble active substances or dispersible substances, and the shell layer water phase can provide good protection and isolation effects and simultaneously meet good skin feel required by cosmetic application. After the active substances are wrapped by the wrapping technology, the unstable active substances can isolate external water, air, ultraviolet rays, other incompatibilities and the like, and reactions such as oxidization, hydrolysis and the like are reduced, so that the stability of the active substances is greatly improved.

Inventors

• MA GUANGYUAN
• QIAO JIAN
• ZHANG HUIJUN
• Bao Rigen
• ZHOU HONGDOU

Assignees

• 上海观辰悦彩生物科技有限公司

Dates

Publication Date

20260512

Application Date

20260319

Claims (10)

1. 1. The oil-in-water microsphere for wrapping the active matter is characterized in that a water phase in the microsphere forms a shell layer to wrap an inner oil phase, the core composition of the inner oil phase comprises the oil-soluble active matter or the dispersible matter, the outer diameter of the microsphere is 0.2-4mm, and the storage modulus G 'of the microsphere is 0.5kPa or more and G' or less and 20kPa or less.
2. 2. The oil-in-water microsphere for encapsulating an active according to claim 1, wherein the microsphere has an inner diameter size of 0.1-3mm and an inner diameter/outer diameter of 0.1-0.9:1.
3. 3. The oil-in-water microsphere for encapsulating an active according to claim 1, wherein the aqueous phase comprises a gelling agent and optionally a cross-linking agent, the gelling agent being present in an amount of 0.1-50% and the cross-linking agent being present in an amount of 0-5% by mass of the aqueous phase.
4. 4. The oil-in-water microsphere for encapsulating an active according to claim 3, wherein the gel comprises at least one of cellulose gum, agar, gelatin, chitosan, gellan gum, carrageenan, guar gum, gum arabic, konjac gum, sodium alginate, locust bean gum, sodium hyaluronate, xanthan gum, sclerotium gum, magnesium aluminum silicate, bentonite, carbomer, acrylic polymers, and the crosslinking agent comprises dipotassium EDTA or calcium EDTA.
5. 5. The oil-in-water microsphere for encapsulating an active of claim 1, wherein the core composition of the inner oil phase further comprises a lipid, the lipid comprising 0.5-99.5% by mass of the inner oil phase.
6. 6. The oil-in-water microsphere for encapsulating an active according to claim 5, wherein the grease comprises at least one of glycerol tri (ethylhexanoate), caprylic/capric triglyceride, coco-caprylate/caprate, isononyl isononanoate, cetyl ethyl hexanoate, candelilla wax, rice bran wax, palm wax, ceresin, spermaceti, montan wax, microcrystalline wax, myristyl myristate, jojoba wax, beeswax, lanolin, jojoba oil, squalane, vegetable oil, and silicone oil.
7. 7. The oil-in-water microsphere for encapsulating an active of claim 1, wherein the oil-soluble active comprises at least one of retinol and its derivatives, vitamin C derivatives, vitamin E and its derivatives, coenzyme Q10, unsaturated plant extracts, sunscreens, essential oils.
8. 8. The oil-in-water microsphere encapsulating an active of claim 1, wherein the dispersible material comprises at least one of zinc oxide, titanium dioxide, iron oxide, pearlescence, mica.
9. 9. A method of preparing oil-in-water microspheres for encapsulating actives according to any one of claims 1-8, wherein the method employs a continuous flow peer shear microfluidic process comprising the steps of: S1, respectively injecting a water phase, an outer oil phase and an inner oil phase into a micro-channel of a micro-fluidic device, wherein the outer oil phase shears the water phase flowing in the same direction into outer liquid drops, and the outer liquid drops flow out to a receiving pipe after being generated; s2, shearing the inner phase oil into the outer liquid drops by the water phase flowing in the same direction to form O/W liquid drops coated with active substances, and collecting and cooling.
10. 10. The preparation method of the micro-channel according to claim 9, wherein the water phase, the outer oil phase and the inner oil phase are respectively injected into the micro-channel through a pneumatic pump, the inner diameter of the micro-channel at the generation position of the inner core is 50-500 um, the outer diameter of the outer liquid drop generation position is 900-2000 um, the flow rate of the solution is controlled by adjusting the parameters of the pressure pump, the corresponding pressure of the water phase is 8-13 kpa, the corresponding pressure of the outer oil phase is 10-18 kpa, and the corresponding pressure of the inner oil phase is 2-8 kpa.

Description

Oil-in-water microsphere for wrapping cosmetic active Technical Field The invention belongs to the technical field of cosmetics and applications, and particularly relates to an oil-in-water (o/w) microsphere for wrapping cosmetic active substances. Background Oil-soluble actives are very common in cosmetics, and many are highly sensitive, such as retinol, coenzyme Q10, most antioxidants, which are exposed to two major natural enemies, oxygen and light. They are susceptible to oxidation, decomposition, isomerization, etc. chemical reactions, leading to deactivation. Taking retinol as an example, retinol is recognized as one of the most effective anti-aging and skin rejuvenating ingredients. However, retinol is extremely sensitive to light, heat, and oxygen and is highly susceptible to degradation and oxidative deactivation in conventional formulations. Traditional cream formulations, while providing basic protection, have far from ideal. This not only results in the product becoming ineffective during shelf life, yellowing in color, and a change in smell, but also results in a much lower dosage actually used by the consumer than the indicated dosage, and a great deal of disruption is achieved. Therefore, it becomes important to develop an innovative protection system that can address unstable oil-soluble actives. The droplet microfluidic technology (Microfluidics) is a technology for generating and controlling monodisperse micro droplets by utilizing an immiscible fluid in a microchannel, and has the advantages of small volume of generated droplets, easily controllable particle size, high monodispersity and the like. The droplet microfluidic technology based on an oil-in-water (O/W) structure is the necessary choice and key technological breakthrough to deal with the pain point of the industry. However, the production of microcapsules for cosmetics by using the droplet microfluidic technology is still in the primary stage, and stability and use feeling cannot be considered. The phenomenon that the stability and the use feeling cannot be simultaneously achieved in the millimeter-sized microcapsule is more remarkable than in the micrometer-sized or nanometer-sized microcapsule. For greater stability, the microspheres are prepared using a single or more rigid wall material (e.g., certain brittle polymers), which may give rise to a pronounced "grainy", "rubbed" or even "gritty" feel when applied, or a hard feel when broken, and difficult breakage. And the microspheres are broken to leave more scraps and sticky matters, are difficult to uniformly spread, have obvious slag feel and film feel, have poor use feel for consumers, are limited in practical application, and are fresh in the market of millimeter-sized oil-in-water microsphere products. CN 117064767A discloses an oil-in-water composition excellent in skin feel, an external skin preparation and a method for preparing the same, which at least comprises water as a medium, oily particles having optical isotropy, oily crystals having optical anisotropy, wherein the oily crystals and the oily particles are both distributed in the water. Compared with the conventional oil-in-water system, the solid oil of the patent application exists in an aqueous phase in a crystal form (the physical form is flaky crystal or lamellar crystal, rather than spherical after being emulsified), so that the spreadability and the freshness are greatly improved, and no blocking feeling is realized. Meanwhile, the solid oil can form a layer of closed film on the surface of the skin, and has good moisturizing performance. However, the oil-in-water composition is an open emulsion system and does not belong to microcapsules nor does it naturally provide a teaching of how to balance stability and feel in use of millimeter-scale microcapsules. Disclosure of Invention The present invention aims to overcome the above-mentioned disadvantages of the prior art by providing an oil-in-water (o/w) capsule for encapsulating (destabilizing oil-soluble) oil-soluble actives. The use feeling of the microbeads is simultaneously considered on the premise of ensuring the stability of the active substances. In the context of this patent application, "actives" refer to "functional ingredients" or "functional ingredients" in cosmetics, e.g., moisturizing and barrier repair agents: ceramides, whitening and freckle-removing agents: ascorbyl palmitate, glabridin, phenethyl resorcinol, anti-aging agents: retinol, retinol palmitate, retinal, polypeptides (e.g., acetyl hexapeptide-8, palmitoyl tripeptide-5, cyclic peptides), coenzyme Q10, sunscreens: octocrylene, ethylhexyl triazone. The active ingredients of the cosmetics are encapsulated in the oily inner core by utilizing a microfluidic technology, the outer layer is a water-based shell layer, and the water-based shell layer is equivalent to a protection cabin. After the active substances are wrapped by the wrapping technology, the unstable active substances can i