JPS60172344A - Preparation of microcapsule - Google Patents

Abstract

PURPOSE:To prepare microcapsules easily by discharging a core component and a shell component simultaneously from a nozzle for the core component and a nozzle for the shell component provided to the outside periphery of the core component nozzle by centrifugal force under hardening conditions of the shell component. CONSTITUTION:A nozzle 1 for a core component is connected to a core componenet tank 6 and a nozzle 2 for a shell component is connected to a shell components tank 7, and a nozzle 3 for a hardening agent is connected to a hardening agent tank 8, respectively, and plural numbers of said nozzles are provided to a rotary head 5. The core component and the shell component are discharged simultaneously from the tip end of the nozzles by a feeding means such as pumps, and are scattered in a housing by the centrifugal force generated by the revolution of the rotary head. In this stage, the core component is encapsulated by the shell component, and the shell component is hardened by the hardening agent.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing microcapsules.

Conventionally known methods for producing microcapsules include a spray method and a coacervation method. These methods have difficulty in completely microencapsulating the core component, and when the core component is liquid, this liquid tends to leach onto the capsule surface, and many capsules tend to aggregate with each other and become independent. It is virtually impossible to encapsulate the structure.

On the other hand, as a method for manufacturing independent capsules that completely cover the core component, the core component and the film component are simultaneously discharged into the coolant from a multiple nozzle having a nozzle for the film component on the outer periphery of the nozzle for the core component, and the surface tension A method of forming a completely covered capsule by the action of With this method, it is virtually impossible to industrially obtain capsules with a diameter of 500 μI11 or less due to the relationship between nozzle diameter and surface tension.

The present invention is characterized in that the multiple nozzles are mounted on a rotary head.
The present invention provides a method for producing fine independent microcapsules by the action of centrifugal force.

That is, the present invention relates to a method for producing microcapsules, characterized in that the core component and the film component are simultaneously released from a core component nozzle and a film component nozzle provided on the outer periphery of the core component by centrifugal force under conditions for curing the film component. .

An example of an apparatus suitable for manufacturing the microcapsules of the present invention is shown in FIGS. 1 and 2.

FIG. 1 is a side sectional view of a rotary head (5) suitable for carrying out the method of the present invention, and FIG. 2 is a view of the rotary head seen from below. The nuclear component nozzle (1) is a nuclear component tank (6),
The film component nozzle (2) is connected to the film component tank (7), and the curing agent nozzle (3) is connected to the curing agent tank (8), respectively, and a plurality of them are arranged on the rotating head (5).

The core component and the film component are simultaneously discharged from the nozzle tip by a supply means such as a pump, and are scattered into the housing by the centrifugal force caused by the rotation of the Shiken head. In this case, the core component is encapsulated by the skin component, and the skin component is hardened by the hardening agent discharged from the hardening agent nozzle. The curing agent does not necessarily need to be ejected from the curing agent nozzle, and the interior of the Howtank may be placed under curing conditions.

Typically, as shown in Figure 1, a hardening agent nozzle is provided around the outer periphery of a film component nozzle, whereby the film components are released from the nozzle and simultaneously come into contact with the hardening agent and become microencapsulated. is carried out efficiently. Although this may be carried out with the rotating head immersed in the curing agent liquid, the action of centrifugal force will be reduced by the resistance caused by the liquid, making it difficult to obtain independent microcapsules. Howtanking may be carried out under a hardening agent gas atmosphere or under a cooling atmosphere.

The core component may be any material as long as it can be discharged from the nozzle in liquid form at room temperature or in a heated state. Specifically, for example, various pharmaceutical aqueous solutions, oils containing dissolved medicines, perfumes, cosmetics, foods, industrial chemicals, etc. are exemplified. These have a viscosity of 500 cps or less, preferably 1 to 30 cI+s, when discharged from the nozzle. 1. j to I O-20
cI! The composition or nozzle temperature is adjusted so that s.

The film component is not compatible with the core component and is liquid when discharged from the nozzle, but any film component that can maintain the film at room temperature after curing may be used. When the core component is an aqueous solution, waxes, hardened oils, resins, etc. are suitable, and a refrigerant such as liquid nitrogen, liquid air, ice water, 161 fat hardening agent, etc. may be used as a hardening agent. Preferably, a refrigerant having a temperature of -20° C. or lower is used, and in particular, these refrigerants are discharged from a hardening agent nozzle. When the core component is oily, it is an oleophobic substance,
For example, gelatin or the like may be used as a film component.

Furthermore, there are various methods such as a method in which an aqueous polymer solution such as a polyacrylic acid aqueous solution is used as a film component, a flocculant such as calcium chloride as a hardening agent, and a force method in which a compound having active hydrogen is crosslinked with a crosslinking agent. A typical combination of a film component and a hardening agent is one in which the film component is hardened by cooling, such as a hardened oil, and the hardening agent is a refrigerant such as liquid nitrogen.

The film component has a viscosity of 500c when released from the nozzle.
ps or less, preferably 1 to 30 cps, especially 10 to 20 cps
Adjust the film component composition or temperature so that cps is achieved.

The rotary head (5) is preferably in the shape of a truncated cone and is provided with multiple nozzles, usually from 3 to 10, on its sides.

The rotation speed is preferably about 1,000 to 40,000 rpm.

The nozzle for the core component has a diameter of 100 to 2000 μm, particularly preferably 300 to 500 μm, and is preferably installed at a position of 2 to 20 cI◎ from the rotation axis of the rotating hand.

The nozzle for the film component is arranged concentrically around the outer periphery of the nozzle for the core component. Slit outer diameter 500-400()μ11. In particular, it is suitable to have a slit-like opening of 600 to 1000 μm.

When provided, the curing agent nozzle is installed concentrically around the outer periphery of the film component nozzle. Outer diameter 1000~8
01) 0 μm1, especially 1200 to 60()00 μm is suitable.

By using the method of the present invention, it is possible to easily obtain microcapsules with a particle size of 100μ or less, in which the core component is substantially covered with a film component.

[Brief explanation of drawings]

FIG. 1 shows a side view of a rotary head for carrying out the method of the invention. FIG. 2 shows a view of the rotary head of FIG. 1 viewed from below. (1) Nozzle for core component (2) Nozzle for film component (3)
Hardening agent nozzle (4) Multiple nozzle (5) Rotating)'
(6) Core component tank (7) Film component tank (8) Hardening agent tank (9) Housing (part of ceiling)

Claims (1)

[Scope of Claims] 1. A microorganism characterized in that a core component and a film component are simultaneously discharged from a core component nozzle and a skin provided on the outer periphery of the core component nozzle under conditions for curing the film component by centrifugal force. Capsule manufacturing method. 2. The manufacturing method according to item 1, wherein the film component is liquid under heating and solid at room temperature, and curing is performed at low temperature. 3. The manufacturing method according to item 2, wherein curing is performed with liquid nitrogen or liquid air. 4. The production method according to item 1, wherein the core component is an aqueous chemical solution. 5. The manufacturing method according to item 1, wherein the core component has a viscosity of 1 to 30 el)s when discharged from a nozzle. 6. Skin +1! W T&, viscosity J change during nozzle discharge is 1
~3()Cl)S The manufacturing method according to item 1. 7. The manufacturing method according to item 1, wherein the centrifugal force is 1xio5-2X108dyne. 8. A plurality of multiple nozzles (4) consisting of a core component nozzle (1), a film component nozzle (2) having at least one slit on its outer periphery, and a slit-shaped curing agent nozzle (3) on its outer periphery. A microcapsule manufacturing device equipped with a rotary head (5) inside the houkung. 9. The diameter of the nuclear component nozzle (1) is 100 to 2000μI
9. The apparatus according to claim 8, which is II. 10. The film component nozzle (2) has one slit,
9. The device according to claim 8, wherein the outside diameter is between 500 and 2500 μm. 11. The outer diameter of the hardening agent nozzle is 1000 to 8000μ.
9. The device according to claim 8, wherein n. 12. The core component is the nozzle 2-20 mm from the center of the rotating head.
9. The device of claim 8, wherein the device is located at cI11. 13. Apparatus according to clause 8, wherein the rotating shaft rotates at 1000-40000 rpm.