JPS6010676Y2 - capsule - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a capsule that independently holds multiple types of substances.

Conventionally, for example, when encapsulating and simultaneously using multiple types of substances, which is inconvenient because they are mixed with hydrophilic substances, etc.
Each substance is separately encapsulated and mixed, and each substance is blocked by a coating membrane in each capsule.

In this case, each substance is encapsulated separately, so the total number of manufacturing steps is quite large.
It requires a lot of equipment and expense.

As mentioned above, the present invention proposes a capsule that can independently hold substances that would be disadvantageous if they were mixed together, and will be described in detail below.

First, to explain the outline of manufacturing the capsule of the present invention, for example, a hydrophilic substance such as a hydrophilic liquid or a hydrophilic liquid emulsified with fine powder is coated with a synthetic resin, and the coating is covered with another fine powder. The basic method is to cover the body with a film of a substance that has been adsorbed onto the body.

More specifically, the hydrophilic substance is coated with a polymer obtained by phase-separating a hydrophobic substance, and a fine powder adsorbed with a required liquid or substance is covered during or after the phase separation. The hydrophilic substance is double coated by adding a suspension dispersed in the hydrophobic substance.

The structure of the capsule thus completed is as shown in the figure.

In the figure, 1 is a core material such as a hydrophilic liquid or solid powder or an emulsion containing both, 2 is a polymer formed by phase separation and is a substantial wall material, and 3 is a phase-separated or phase-separated core material. The fine powder added after completion of the process, and 4 indicate the substances adsorbed or contained in the fine powder 3, respectively.

As the core substance 1, water, aqueous solutions of organic and inorganic substances, hydrophilic powder pigments, hydrophilic emulsions, etc. can be used.

As the wall material 2, ethyl cellulose can be used, preferably a polymer solvent dissolved in a hydrophobic medium.

The fine powder 3 includes fine powder, such as metal oxides such as aluminum oxide, silicon oxide, magnesium oxide, and titanium dioxide, cadmium sulfide, zinc sulfide, calcium carbonate, zinc carbonate, kaolin, activated clay, and glass. Fine powder, synthetic resin fine powder, etc. can be used.

The substance 4 is not particularly limited as long as it can be adsorbed or contained in the fine powder 3, and for example, colored pigments or dyes can be used.

Next, the case of making a capsule as shown in the figure will be explained in detail.

That is, in order to cover a core material such as a hydrophilic material with a wall material that has been phase-separated from an organic solvent, the core material, such as a hydrophilic material or an aqueous solution thereof, and the wall material, such as ethyl cellulose, are each dissolved in a solvent. Emulsify the substance using a homogenizer to create an emulsion of hydrophilic substances.

A non-solvent is added to this emulsion to cause phase separation, and a layer of a concentrated solution of ethyl cellulose is formed around a minute amount of hydrophilic substance to form a coating.

During this process, fine powder such as titanium dioxide adsorbed or containing liquid or solid substances is suspended in a non-solvent and the fine powder is converted into a concentrated solution of ethyl cellulose during or after phase separation. Gather into layers,
A hydrophilic substance is coated with ethyl cellulose, and the outside is coated with fine powder or a mixture of fine powder and ethyl cellulose to form a capsule.

At this time, it goes without saying that the above-mentioned substances are still adsorbed or contained in the fine powder.

In this manner, after adding an appropriate amount of the substance adsorption fine powder dispersed in a non-solvent during or after the phase separation, the mixture is cooled to about 5°C to fix the ethyl cellulose.

Since this initially contains a solvent in which the ethyl cellulose was dissolved, a complete wall material was not formed, so a non-solvent was added to replace the solvent and the ethyl cellulose capsules were completely dissolved. The capsule is completed as a solvent system.

Dry capsules can be obtained by drying and removing the nonsolvent by spray drying, freeze drying, or the like.

Now, in this capsule, if the core substance 1 and the required substance 4 adsorbed or contained in the fine powder 3 are an electron donor substance and an electron acceptor substance, respectively, they will come into contact and react for the first time by destroying the capsule. Because it can be done,
You can fully demonstrate the characteristics of this capsule.

Incidentally, here, the reaction between the required substance 4 and the core substance 1 is '
The meaning of ``reaction'' is to express the exchange of one electron, and even though part of the structure may change slightly, substance A and substance B react to form substance C. This is not a reaction in the sense that it will be rawhide.

Therefore, the fine powder 3 serves as an auxiliary agent for efficient exchange of one electron.

For example, if the core substance 1, which is a hydrophilic substance, is covered with a fine powder 3 of a pigment with great hiding power, such as titanium dioxide, the core substance 1 can be stably protected from light, and the capsules can coagulate together. It is possible to prevent coarsening.

Furthermore, even when the dried capsules are dispersed in an aqueous solution, it is possible to allow titanium dioxide, which has good dispersibility in water, to come into contact with water, without contacting ethyl cellulose, which has poor wettability with water, with water. Therefore, the capsule has good separation property against water.

Next, two or three specific manufacturing examples will be shown.

Example 1 2.3.5-triphenyltetrazolium chloride 1
1.5 parts of lithium chloride was dissolved in a mixed solution of 25 parts of polyethylene glycol (degree of polymerization 400) and 75 parts of water.
Take 10 [cc] of the aqueous solution added twice as a core material, and add this and 1.6 [cc] of ethyl cellulose to 40 [cc] of carbon tetrachloride.
Nonionic surfactant (HLB) is added to the solution dissolved in (cc).
Add 0.4 [skin] of 3.5) and emulsify with a homogenizer for about 1 minute.

Next, 40 mt of carbon tetrachloride was gradually added with stirring, and further 80 mt of petroleum ether as a non-solvent was added with stirring.
] Add.

Separately, prepare titanium dioxide (anatase type, particle size 0.1~
0.2P) 10(f) to about 0 nonionic surfactant
．． A suspension was made by dispersing it for several hours in 30 (cc) of petroleum ether to which 1% was added, and the suspension was divided into three equal parts of 1/3 each.

Among them, benzoylleucomethylene blue fine powder is added to the In amount and stirred to prepare a mixture in which the fine powder is sufficiently adsorbed and impregnated into titanium dioxide.

Now, as mentioned above, 80 [rrLL] of petroleum ether was finally added to the solution containing the core substance, but 1/3 of the titanium dioxide-petroleum ether suspension was added to this solution, and the benzoyl Add the titanium dioxide-petroleum ether suspension to which leucomethylene blue fine powder has been added, and finally add the remaining 1/3 of the titanium dioxide-petroleum ether suspension.

By carrying out the above bonding process, phase separation of ethyl cellulose is carried out, and the core material 2,3,5-triphenyltetrazolium chloride is coated with the wall material ethyl cellulose. A coating is formed.

However, during this phase separation, only a layer of concentrated solution of ethyl cellulose is present, and no film is formed.

Now, when the phase separation is completed, the ethyl cellulose is fixed by cooling to 5 [°C].

Then, in order to remove excess carbon tetrachloride from this system, the capsules are precipitated, and the petroleum ether is exchanged two or three times by decantation to create a complete petroleum ether-capsule system, and a stable capsule is completed. do.

This encapsulation solution is dried using a spray dryer.

The dried capsules thus obtained have a particle size of 50 to 10
It was in the form of a white powder with a diameter of 0 [μ], and the yield was 85 [%].

When this dried capsule is placed under the irradiation light of an ultra-high-pressure mercury lamp, it becomes clear that the core material, 2,3,5-triphenyltetrazolium chloride, is red due to the photoreduction of α.
Color development of formazan was observed.

Furthermore, when the dried capsules were added to hydrogen peroxide, a blue color was gradually developed, confirming that benzoylleucomethylene blue was contained.

Example 2 2-(P-indophenyl)- instead of 2,3.5)-diphenyltetrathulium chloride used in Example 1
Similar effects were confirmed when using 3-(P-nitrophenyl)-5-phenyltetrazolium chloride, aluminum oxide fine powder instead of titanium dioxide, and crystal violet lactam instead of benzoylleucomethylene blue.

Example 3 0.1 (9) of benzoyl leucomethylene blue to 10 parts of water
Example 1. (cc) was used as a material for the core material. Encapsulate with an ethyl cellulose film using the same method as above.

The titanium dioxide-petroleum ether suspension added during phase separation contains 3.3'-0.2 (5F) of titanium dioxide.
When (4,4'-biphenylene)-bis[25-diphenyltetrathulium chloride] is adsorbed and used,
The same results as in Example 1 were obtained.

As can be seen from the above description, according to the present invention, substances that would be inconvenient to contain in a mixed manner can be held independently in one capsule.

Moreover, when manufacturing capsules, they can be made during the manufacturing process.

In particular, coating with fine powder that adsorbs or contains a substance with properties different from that of the core material is carried out during the formation of the wall material, and therefore, the formation of the wall and the coating with fine powder are formed almost at the same time. For example, as seen in Japanese Patent Publication No. 37-12381, the core material is surrounded by a wall obtained by gelling and hardening a polymer material deposit, and then a second wall is formed on the core material. It is simple to manufacture compared to coating with reactants.

In addition, if the outer fine powder is appropriately selected, the capsule can be
Can be well dispersed in various liquids.

That is, if a hydrophilic substance is selected as the fine powder,
Regardless of the nature of the wall material surrounding the core material, it can be well dispersed in hydrophilic liquids, such as water.

Therefore, the hydrophilic liquid serving as the core substance and the encapsulating aqueous solution containing the same can coexist under different hydrogen ion concentrations.

Furthermore, the use of fine powder that adsorbs or contains a substance with properties different from that of the core substance brings about an extremely large effect.

That is, for example, in the above embodiment, the core substance (substance 1') and the substance adsorbed or contained in the fine powder (substance 3') (substance 4') are not mixed. This method is effective for manufacturing a capsule having a structure in which the substance 3' and the substance 4' must not be separated from each other.

For example, when one color-forming particle develops either red or blue color due to oxidation or reduction, substance 1' (red color-forming substance) and substance 4' (blue color-forming substance) They must not be mixed, and the substance 3' (the reaction catalyst and the substance that serves as a masking and stabilizing agent) and the substance 4' must not exist separately.

If they are separated, the action of the substance 3' will not be sufficient and the effect will be reduced.

In such a case, in the present invention, substance 4 is added to substance 3'.
Since it can be coated by adsorbing or containing ', the purpose can be fully achieved.

[Brief explanation of drawings]

The figure shows a partially cut section of a capsule according to an embodiment of the present invention. In the figure, 1 is a core material, 2 is a wall material, 3 is a fine powder, and 4 is a
indicate substances adsorbed or contained in the fine powder 3, respectively.

Claims (1)

[Scope of utility model registration request] A core material that develops color upon oxidation or reduction, a wall material that forms a wall that covers and protects the core material, and a wall material that is contained within the wall formed of the wall material that protects the core material and protects the core material. A fine powder that helps color the substance and a substance that develops a color different from that of the core substance, and a wall formed of the wall material containing the fine powder in a mixed or adsorbed state. A capsule comprising a substance that protects a core substance and develops a color different from that of the core substance upon reduction or oxidation.