JPH11188079A - Method of manufacturing seamless capsule grain - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily manufacture capsule grains so that the thickness of their coatings is uniform even if each liquid that is emitted from each nozzle has low interfacial tension between each the liquid and its surface. SOLUTION: A multiple nozzle that is composed of plural nozzles which are arranged in a concentric circle as a layer is used for this manufacturing method. Each nozzle that composes of the multiple nozzle has a straight pipe of which the taper is smaller than l/10 at the emitting part of the multiple nozzle. The length of the straight pipe should be longer than that of each nozzle to which the pipe corresponds. The end of the emitting hole of the inner nozzles should be on the same level as that of the most outer nozzles or it should be interior.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing seamless capsule particles. More specifically, a seamless material containing a liquid having a low interfacial tension at the liquid-liquid surface between adjacent liquids discharged from each nozzle, which can be suitably used for pharmaceuticals, foods, luxury goods, bath products, cleaning products, and the like. The present invention relates to a method for producing capsule particles.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a seamless capsule, a multiple nozzle having a tapered inner wall of one nozzle has been used (JP-A-59-112833, JP-A-3-52639). Bulletin, Tokuhei 3-0333
No. 38, JP-A-7-53356, JP-A-8-
No. 10313).

[0003] However, when the multiple nozzles are used, the multilayer liquid column jet when the liquid for forming capsules is discharged from the multiple nozzles is disturbed, so that the thickness of the obtained capsule particle film becomes uneven, There is a disadvantage that it is difficult to perform encapsulation using a content liquid having a liquid-liquid surface tension of 20 mN / m or less between liquids adjacent to each other discharged from each nozzle.

Therefore, as an apparatus for making the thickness of the capsule particle film uniform, there has been proposed a seamless capsule manufacturing apparatus in which the position of the multiple nozzles can be adjusted in a direction crossing the flow of the curing liquid. (Japanese Patent Laid-Open No. 5-13)
No. 8012).

[0005] However, when the above-mentioned seamless capsule manufacturing apparatus is used, a complicated operation of searching for the optimum position of each nozzle according to the composition of the content liquid and the coating liquid is required. Further, when manufacturing various kinds of capsules, the optimum position of each nozzle is different depending on the composition of the capsule, so that the optimum position must be adjusted accurately, and a complicated apparatus for moving each nozzle is required. There is a drawback that requires.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and has been made in view of the above-mentioned prior art, and when manufacturing seamless capsule particles, the liquid-liquid level of adjacent liquids discharged from each nozzle is reduced. It is an object of the present invention to provide a method capable of easily producing capsule particles having a uniform film thickness even when the interfacial tension is low.

[0007]

That is, the gist of the present invention is as follows.
A method for producing seamless capsule particles using multiple nozzles formed by concentrically laminating a plurality of nozzles with a gap therebetween, wherein each nozzle constituting the multiple nozzle is a discharge unit of the multiple nozzle. Has a straight tubular portion with a taper of 1/10 or less, the length of the straight tubular portion of each nozzle is equal to or more than the inner diameter of each corresponding nozzle, and the inner side of the outermost nozzle constituting the multiple nozzle Wherein the end face of the discharge port of the nozzle is located on the same plane as the end face of the discharge port of the outermost nozzle, or is located inside the end face of the discharge port of the outermost nozzle. It relates to a manufacturing method.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for producing capsule particles of the present invention, each nozzle constituting a multi-nozzle has a straight tubular portion having a taper of 1/10 or less at a discharge portion of the multi-nozzle. The length of the straight tubular portion of the nozzle is equal to or larger than the inner diameter of each corresponding nozzle, and the end face of the outlet of the nozzle inside the outermost nozzle constituting the multiple nozzle is the outlet of the outermost nozzle. Is characterized in that multiple nozzles are used on the same plane as the end face of the nozzle or inside the end face of the discharge port of the outermost nozzle.

In the present invention, since the multiple nozzles are used, even when the liquid-liquid level interfacial tension between adjacent liquids discharged from each nozzle is low,
An excellent effect that capsule particles having a uniform film thickness can be easily produced is exhibited.

The number of laminations of the plurality of nozzles constituting the multi-nozzle is not particularly limited, and may be appropriately determined according to the layer of capsule particles to be formed.

For example, if the capsule has one inner layer, the number of nozzles may be double, and if the capsule has two layers, the number of nozzles may be two. It suffices if it is triple.

According to the present invention, capsule particles having two or more inner layers, which have been difficult to produce, can be produced particularly easily. In this case, the number of nozzles constituting the multiple nozzles is three or more.

The gap between the plurality of stacked nozzles serves as a passage for the coating liquid component or the content liquid component. The nozzles are stacked concentrically. The central axis of each nozzle may not be the same axis, but is preferably the same axis from the viewpoint of obtaining uniform capsule particles.

One of the major features of the present invention is that each of the nozzles used in the multiple nozzle has a straight tubular portion having a taper of 1/10 or less at the discharge portion.

Thus, the nozzle has a taper of 1/1.
Since it has a straight tubular portion of 0 or less, even when the liquid-liquid level interfacial tension between adjacent liquids discharged from each nozzle is low, it is easy to produce capsule particles having a uniform film thickness. The excellent property that can be obtained is exhibited.

The nozzle having the straight tubular portion may be provided with a taper. However, even when a liquid having a low interfacial tension is used, capsule particles having a uniform film thickness can be easily formed. From the viewpoint that the taper can be manufactured, the taper is 1/10 or less, preferably 1/50 or less, more preferably 1/100 or less, and in particular, the taper is not provided. preferable.

The cross-sectional shape perpendicular to the axis of each nozzle constituting the multi-nozzle is not particularly limited.
Examples include polygons such as quadrilaterals, ellipses, and circles.
Among these shapes, the circular shape is preferable from the viewpoint of obtaining capsule particles having a uniform shape.

The straight tubular portion of the nozzle refers to a portion having a straight pipe shape in the discharge portion of the multiple nozzle. Specifically, for example, when the multiple nozzle shown in FIG. taking as an example, L ₂ moieties in L ₁ portion, the middle nozzle 3 at the inner nozzle 2, the outer nozzle 4
L ₃ portion corresponds in.

In the present invention, there is also one great feature in that the length of each of the straight tubular portions is equal to or larger than the inner diameter of each nozzle. With such a configuration, discharge is performed from each nozzle. Capsule particles can be easily produced even when a liquid having a low interfacial tension of liquid-liquid level between adjacent liquids of, for example, 20 mN / m or less is used.

The fact that the length of the straight tubular portion of the nozzle is equal to or larger than the inner diameter of the nozzle means, specifically, for example, in the triple nozzle 1 shown in FIG. , The length L ₁ of the straight tubular portion of the inner nozzle 2 is the inner diameter d ₁
It means above.

The length of the straight tubular portion of each nozzle is preferably at least twice the inner diameter of each nozzle, more preferably at least three times, from the viewpoint of obtaining more uniform capsule particles. It is particularly preferred that the ratio be 5 times or more.

Further, in the present invention, the end face of the discharge port of the nozzle located inside the outermost nozzle (the outermost nozzle of the multiple nozzle) constituting the multiple nozzle is the discharge port of the outermost nozzle. Another major feature is that a configuration is adopted in which it is located on the same plane as the end face of the outermost nozzle or inside the end face of the discharge port of the outermost nozzle.

In the present invention, by adopting such a configuration, the interfacial tension of the liquid-liquid surface between adjacent liquids discharged from each nozzle is, for example, 20 as described above.
Even when a liquid having an interfacial tension of not more than mN / m is used, capsule particles can be easily produced.

Specifically, the fact that the end face of the discharge port of the nozzle located inside the outermost nozzle constituting the multiple nozzle is coplanar with the end face of the discharge port of the outermost nozzle means, for example, In the triple nozzle 1 as shown in FIG. 1, the end face P of the discharge port of the outer nozzle 4 which is the outermost nozzle
Means that the end faces of the discharge ports of the inner nozzle 2 and the middle nozzle 3 are on the same plane.

In the present specification, "coplanar" means that the end face of the discharge port of the nozzle located inside the outermost nozzle is -10 to 1 of the inner diameter of the discharge port of the outermost nozzle.
Within the range of 0%, it means that it may protrude or enter the inside of the side surface of the discharge port of the outermost nozzle.

Further, the fact that the end face of the discharge port of the nozzle located inside the outermost nozzle constituting the multiple nozzle is located inside the end face of the outermost nozzle is specifically described in, for example, FIG. In the triple nozzle 1 as shown in FIG. 1, when the outer nozzle 4 which is the outermost nozzle and the middle nozzle 3 which is inside the outer nozzle 4 are taken as an example, the end of the outlet of the middle nozzle 3 As shown in FIG. 1, this means that the length is longer than the end of the discharge port of the outer nozzle 4 by the length h and inside the end face P of the discharge port of the outer nozzle 4.

When the multi-nozzle is constituted by a plurality of nozzles other than the outermost nozzle, the end faces of the discharge ports of the inner nozzles are all flush with the end face of the discharge port of the outermost nozzle. Although it is preferable to produce uniform capsule particles, the end faces of the discharge ports of the plurality of nozzles inside the outermost nozzle are only part of the end faces of the discharge ports of the outermost nozzle. It is more preferable that all of the plurality of nozzles inside the outermost nozzle are inside the end face of the discharge port of the outermost nozzle.

In the present invention, the end face of the discharge port of the nozzle located inside the outermost nozzle is within a range of within twice the inner diameter of the outermost nozzle, preferably within a range of within one time. Being located inside the end face of the discharge port of the outermost nozzle, for example, has a low interfacial tension in which the liquid-liquid surface interfacial tension between adjacent liquids discharged from each nozzle is 20 mN / m or less. Even when a liquid is used, it is desirable because capsule particles can be easily produced.

In the case where the multi-nozzle is composed of three or more nozzles, the end face of the discharge port of the nozzle located inside the outermost nozzle projects beyond the plane of the end face of the discharge port of the outermost nozzle. If not, they do not all need to be on the same plane, and may be in an uneven relationship.However, in the present invention, the nozzles inside the outermost nozzle are sequentially arranged in the central direction of the multi-nozzle. It is preferable that the outermost nozzle is formed so as to be recessed from the end face of the discharge port. In this case, the steps between the nozzles inside the outermost nozzle may be the same or different. In the present invention, when each of the nozzles inside the outermost nozzle is sequentially formed in the center direction of the multiple nozzles so as to be recessed from the end face of the discharge port of the outermost nozzle, a step between the nozzles is formed. Is usually preferably about 10 to 100% of the inner diameter of the outermost nozzle from the viewpoint of forming uniform capsules.

The outer shape of the outermost nozzle constituting the multiple nozzle is not particularly limited. For example, the outer cross-sectional shape may be a straight tube or a tapered shape. Among these shapes, the tapered shape is such that when encapsulation is performed with the tip of the multi-nozzle immersed in the curing liquid, the curing liquid smoothly enters the liquid for forming capsule particles,
This is a preferable shape because capsule particles can be produced in a stable state.

The tapered shape is not particularly limited. For example, the tapered shape may be a shape having a continuously changing taper, for example, a parabolic shape or a curved shape having an arbitrary radius.

Although there is no particular limitation on the inclination of the taper, a portion (end point) having a length equal to the outer shape of the end of the discharge port of the outermost nozzle from the start point of the taper on the side closer to the end face of the outermost nozzle. The average taper is preferably 5/1 or less, for example, in order to prevent the encapsulation yield from decreasing when forming multilayer droplets in the downward curing liquid, and 2/1 or less. More preferably, it is particularly preferably at most 1/1.

The length of the taper is not particularly limited. For example, when a multilayer liquid droplet is formed in a descending curing liquid, the curing liquid flows smoothly to improve the encapsulation yield. In view of this, the length is preferably equal to or greater than the outer diameter of the end of the discharge port of the outermost nozzle, more preferably equal to or greater than twice the outer diameter, and particularly preferably equal to or greater than 5 times. preferable.

The outer shape of the outermost nozzle may be any shape such as polygonal, elliptical or circular in cross section perpendicular to the axis, but in the present invention, it is preferably circular.

The length of the linear portion at the tip of the discharge portion of the outermost nozzle (the portion between the end of the discharge port and the starting point of the tapered shape: the portion indicated by Q in FIG. 1) is particularly long. Although not limited, the outer diameter of the outermost nozzle is 5 times or less, preferably 3 times or less, more preferably 1 time or less, and particularly preferably 0.5 times or less. It is desirable to avoid a decrease in the encapsulation yield when forming droplets.

The thickness of the nozzle in the linear portion at the tip of the discharge portion of the outermost nozzle is preferably not less than 0.03 mm from the viewpoint of nozzle strength. When performing encapsulation, it is preferably 5 mm or less, more preferably 2 mm or less, and still more preferably 1 mm or less, in order to prevent the thickness of the formed capsule film from becoming uneven. preferable.

The inner diameter of the discharge port of the outermost nozzle is appropriately limited depending on the size of the obtained capsule particles. In the present invention, from the viewpoint of producing capsule particles having a uniform film, usually, The size of the capsule to be manufactured
It is preferably 500%, preferably 20 to 300%, more preferably 30 to 200%, particularly preferably 50 to 150%.

The outermost nozzle is provided on the inner surface of the discharge portion.
Straight tubular part (L in FIG. 1) _Three) Length
Without limitation, obtain capsules with uniform film thickness
From the viewpoint of the inner diameter of the outermost nozzle,
It is preferably 10 times or less the inner diameter of the nozzle.

The thickness of the nozzles inside the outermost nozzles constituting the multi-nozzle is preferably 1% or more of the inner diameter of each nozzle to improve the concentricity of the nozzles and improve encapsulation. Is desirable, and 3
0% or less, preferably 20% or less, more preferably 1% or less.
5% or less is desirable from the viewpoint of improving the capsule yield of a liquid having a low interfacial tension in which the liquid-liquid surface interfacial tension between adjacent liquids discharged from each nozzle is, for example, 20 mN / m or less.

As described above, the multiple nozzles used in the present invention are formed by concentrically laminating a plurality of nozzles with a gap provided between them, and a liquid ejected through the gap provided between the nozzles is provided. Passage. Such a gap is appropriately selected such that the maximum and minimum flow velocity ratio of each liquid discharged from the discharge port of each nozzle in the discharge port is in the range of 1 to 5 times, but the pressure loss in the flow path is reduced. To do so,
It is desirable that the thickness be 0.03 mm or more, preferably 0.05 mm or more, more preferably 0.07 mm or more.

The maximum and minimum flow velocity ratio of each liquid discharged from the discharge port of each nozzle is not particularly limited, but in order to facilitate encapsulation of a liquid having a low interfacial tension,
Usually, it is desirable that it is preferably 1 to 3 times, particularly preferably 1 to 2 times. Each flow rate can be determined by dividing the flow rate of the liquid flowing into each nozzle per unit time by the area of the discharge port. At this time,
In a multiple nozzle, as shown in FIG.
The angle α formed by the taper provided up to the straight tubular portion is not particularly limited, but is usually 0.1 to 85 °.
It is preferred that it is about.

The material of each nozzle constituting the multi-nozzle is not particularly limited, but various steels represented by stainless steel, aluminum, copper, titanium, various alloys, glass, ceramics, fluororesin, plastics, etc. Is raised. Among these, stainless steel represented by SUS304, SUS430, SUS316, etc. is preferable from the viewpoint of workability and durability.

The liquid discharged from the multiple nozzles is composed of a coating liquid component and a content liquid component. The types of these liquids are appropriately selected depending on the structure of the capsule, and adjacent liquids ejected from the multiple nozzles are selected such that they are substantially not mixed or hardly mixed like water and oil. As the content liquid component, an oily component, a water-soluble component, a surfactant component, a heterogeneous oil-in-water dispersion, a water-in-oil dispersion and a suspension solution which are homogeneous solutions are used.

Specific examples of the liquid and the curing liquid discharged from the multiple nozzles include, for example, liquids described in JP-A-6-55060, and these liquids are appropriately used depending on the application. Can be selected and used.

The coating liquid does not necessarily need to be discharged from the outermost nozzle.
When a double nozzle is used, a capsule liquid having two inner layers can be manufactured by discharging the coating liquid from the second nozzle from the outside of the quadruple nozzle and discharging the curing liquid from the outermost nozzle.

In producing seamless capsule particles,
The seamless capsule particles can be obtained by vibrating the multilayer liquid column discharged from the multiple nozzles to generate small droplets. There is no particular limitation on the method of applying vibration to the multilayer liquid column. For example, a method of applying vibration to the multilayer liquid column by applying vibration to the nozzle, or a method of discharging one or more of the liquids discharged from the nozzle from the nozzle. A method of applying vibration before being performed, a method of applying vibration to the multilayer liquid column by the pulsating flow of the cooling liquid of the external phase of the multilayer liquid column discharged from the nozzle, setting a vibration ring on the outer periphery of the multilayer liquid column discharged from the nozzle, A method of giving vibration to the multilayer liquid column is exemplified. Among these methods, in order to efficiently perform encapsulation using a liquid having a low interfacial tension, a method of applying a vibration to at least one of the liquids discharged from the nozzle before the liquid is discharged from the nozzle. preferable.

It is preferable that the frequency given to the multilayer liquid column is appropriately selected according to the liquid column linear velocity and the liquid viscosity used. The frequency to be given is not limited, but is usually preferably about 1 to 2000 Hz.

In the present invention, a method of obtaining liquid droplets without applying vibration can be used.

The multilayer droplet may be generated in any of a gas phase and a liquid phase. When the liquid is formed in the liquid phase, the liquid may be formed in a static liquid without a liquid flow, but it is preferable to form the liquid in a descending flow or an ascending flow using a droplet forming tube. Further, the position of the end face of the nozzle may be either a gas phase or a liquid phase, but is preferably a liquid phase when forming a multilayer droplet in the liquid phase.

The temperature of each liquid discharged from the multi-layer nozzle is not particularly limited, but is usually preferably about 0 to 100 ° C.

The viscosity of each liquid discharged from the multiple nozzles is
Although not particularly limited, when measured with a B-type viscometer, the temperature of each of the discharged liquids is usually 0.1 to 1000.
cP, preferably 1 to 800 cP.

Conventionally, the interfacial tension of the liquid-liquid surface between adjacent liquids discharged from multiple nozzles has been appropriately selected to be 20 to 60 mN / m in order to produce uniform capsule particles.

On the other hand, in the manufacturing method of the present invention, since the multiple nozzle as described above is used,
Even when a liquid discharged from each nozzle and having a liquid-liquid level interfacial tension between adjacent liquids of 20 mN / m or less is used, uniform seamless capsule particles can be easily produced. .

The interfacial tension is such that the end face of the pipe is perpendicular to the longitudinal direction of the pipe, and the diameter a (m
m) using a pipette with a scale of 1 mm having a hole in which a liquid having a relatively high specific gravity is put into the pipette, and an end of the pipette is inserted into a liquid having a low specific gravity, The liquid in the liquid is adjusted by a cock so that the liquid droplet generation interval is 1 second or more, the number of liquid droplets until a certain amount of liquid flows out, and the volume of the liquid flowing out is divided by the number of liquid droplets. After determining the size of the droplet and calculating the equivalent diameter d assuming that the droplet is spherical, the formula: d / a = 1.74 (σ / (a ² gΔρ)) ^0.38 [wherein a is the capillary diameter (m), d is the size of the droplet (m), g is the gravitational acceleration (9.8 kg / sec ² ), σ
Is the interfacial tension (mN / m), Δρ is the density difference (kg / m ³ )
Is shown).

[0055]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention.

[Composition of Capsule Solution] (A) Coating Solution 40 parts by weight of gelatin AP-100 (trade name, manufactured by Nitta Gelatin Co., Ltd.), 4 parts by weight of glycerin, and 56 parts by weight of ion-exchanged water were stirred at 70 ° C. After being dissolved and deaerated, it was used as a coating solution.

(B) Oil Component A Solution 30 parts by weight of a citrus fruit-based flavor and 70 parts by weight of tri (caprylate capric acid) glycerin were mixed by stirring at room temperature to prepare an oily component A solution. The viscosity is 20 with a B-type viscometer.
cP (temperature 25 ° C.). The specific gravity was 0.946. The interfacial tension with water was 12.0 mN / m.

(C) Oily component B liquid 24.2 parts by weight of bergamot flavor and 75.8 parts by weight of isopropyl palmitate were mixed by stirring to obtain an oily component B liquid. The viscosity was measured at 9.3 cP with a B-type viscometer (temperature 25
° C). The specific gravity was 0.861. The interfacial tension with water was 25.3 mN / m.

(D) Oil-in-water dispersion A solution prepared by dissolving 20 parts by weight of a bergamot-based flavor and 12.5 parts by weight of a surfactant, polyoxyethylene (6) sorbitan monooleate, was stirred with a homomixer and ion-exchanged water. 67.5 parts by weight was added dropwise over 5 minutes, and the mixture was subjected to phase inversion emulsification to obtain an oil-in-water dispersion. The viscosity is 40.5c with a B-type viscometer.
P (temperature 25 ° C.). The specific gravity was 0.985. The interfacial tension of the oil component B with respect to the oil-in-water dispersion was 3.7 mN / m.

(E) Curing liquid Tri (caprylic capric acid) glycerin was used as a curing liquid.

The interfacial tension was determined by the following equation using a capillary having an inner diameter of 1 mm. The interfacial tension with respect to the coating liquid was set to be substantially equal to that of water.

D / a = 1.74 (σ / (a ² gΔρ)) ^0.38 [where a is the capillary diameter, d is the size of the droplet, g is the gravitational acceleration, σ is the interfacial tension, and Δρ is the density. Show the difference)

[Type of Nozzle] In each embodiment, FIG.
The nozzle having the structure shown in FIG. Note that FIG.
The abbreviations described therein mean those described in Table 1. When the nozzle used is a double nozzle, the inner nozzle is omitted.

In Table 1, a negative value ("-") indicates that the outermost nozzle protrudes from the end face of the discharge port.

[0065]

[Table 1]

Example 1 Using the nozzle A, a coating liquid of 70 ° C. was oscillated from the outermost nozzle at a flow rate of 11.2 ml / min, and an oily component B liquid was oscillated at a flow rate of 25.0 ml / min from the innermost nozzle at a frequency of 34 Hz. And simultaneously discharged into a curing liquid at 5 ° C. to obtain seamless capsule particles. The capsule particles are dried at room temperature so that the water content of the capsules is 10% or less, and the average particle diameter is 3%.
mm capsule particles were obtained.

The yield of the obtained capsule particles was 97%. The uniformity of the film thickness was 129% as determined according to the following method.

[Uniformity of film thickness] After the capsule was dried, its center was cut and the thickness of the film at the cut end was observed with a microscope (× 200). Measure the film thickness. In addition, observation was performed about five obtained capsules.

The uniformity of the coating thickness was determined according to the formula: [Uniformity of coating thickness] = (average of maximum coating thickness 最大 average of minimum coating thickness) × 100 (%). The uniformity of the film thickness is 100%
The closer to, the more uniform the film thickness.

Example 2 Seamless capsule particles were obtained in the same manner as in Example 1 except that the nozzle B was used.

The yield was 96%. The uniformity of the film thickness was 133%.

Example 3 Seamless capsule particles were obtained in the same manner as in Example 1 except that the nozzle C was used and the oil component A was used as the innermost liquid.

The yield was 99%. The uniformity of the film thickness was 103%.

Example 4 Using the nozzle D, the coating liquid at 70 ° C. was flowed from the outermost nozzle at a flow rate of 12.5 ml / min, and the oil component B liquid was flowed from the middle nozzle at a flow rate of 25.1 ml / min. The dispersion was vibrated at a flow rate of 15.0 ml / min at a frequency of 40 Hz and simultaneously discharged into a curing liquid at 5 ° C. to obtain seamless capsule particles. The capsule particles were dried at room temperature so that the water content of the capsules was 10% or less, to obtain capsule particles having an average particle diameter of 3 mm.

The yield was 95%. The uniformity of the film thickness was 125%.

Example 5 Seamless capsule particles were obtained in the same manner as in Example 4 except that the nozzle E was used.

The yield was 97%. The uniformity of the film thickness was 104%.

Comparative Example 1 Capsule particles were obtained in the same manner as in Example 1 except that the nozzle F was used.

The yield was 97%, but the uniformity of the film thickness was 217%.

Comparative Example 2 Capsule particles were obtained in the same manner as in Example 3 except that the nozzle G was used.

The yield was 21% and the uniformity of the film thickness was 24.
3%.

Comparative Example 3 Capsule particles were obtained in the same manner as in Example 3 except that the nozzle H was used.

The yield was 13% and the uniformity of the film thickness was 27%.
5%.

Comparative Example 4 Capsule particles were obtained in the same manner as in Example 4 except that the nozzle I was used.

The yield is 5% and the uniformity of the film thickness is 235.
%Met.

Comparative Example 5 Capsule particles were produced in the same manner as in Example 4 except that the nozzle J was used, but no capsule particles were obtained.

From the results of Examples 1 to 5, it is found that when the multiple nozzles of the present invention are used, compared with the case where the nozzles of Comparative Examples 1 to 5 are used, the liquid discharged from each nozzle is It is understood that capsule particles having a uniform film thickness can be obtained even when the liquid surface has a low interfacial tension.

The present invention includes the following inventions. (1) A multiple nozzle in which a plurality of nozzles are stacked concentrically with a gap therebetween, and each of the nozzles constituting the multiple nozzle has a taper of 1/10 or less at a discharge portion of the multiple nozzle. The straight tube portion of each nozzle, the length of the straight tube portion of each nozzle is equal to or more than the inner diameter of each corresponding nozzle, and the discharge port of the nozzle inside the outermost nozzle constituting the multiple nozzle A multi-nozzle, wherein an end face is on the same plane as an end face of the discharge port of the outermost nozzle, or is located inside the end face of the discharge port of the outermost nozzle. (2) The nozzle according to (1), wherein the end faces of the discharge ports of the nozzles located inside the outermost nozzles constituting the multiple nozzles are all flush with the end faces of the discharge ports of the outermost nozzle. Multiple nozzles.

[0089]

By using the multiple nozzles of the present invention, capsule particles having a uniform film thickness can be easily formed even when the liquid-liquid level interfacial tension between the liquids discharged from each nozzle is low. The effect that it can be manufactured is produced.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing one embodiment of a multiple nozzle used in the manufacturing method of the present invention.

FIG. 2 is a schematic explanatory view of a multiple nozzle used in Examples and Comparative Examples of the present invention.

[Explanation of symbols]

 1 triple nozzle 2 inner nozzle 3 middle nozzle 4 outer nozzle

Claims (6)

[Claims] 1. A method for producing seamless capsule particles using multiple nozzles in which a plurality of nozzles are stacked concentrically with a gap provided therebetween, wherein each of the nozzles constituting the multiple nozzles is The discharge portion of the multiple nozzle has a straight tubular portion having a taper of 1/10 or less, and the length of the straight tubular portion of each nozzle is equal to or more than the inner diameter of each corresponding nozzle. The end face of the discharge port of the nozzle located inside the outer nozzle is on the same plane as the end face of the discharge port of the outermost nozzle, or is located inside the end face of the discharge port of the outermost nozzle. A method for producing seamless capsule particles. 2. The discharge nozzle according to claim 1, wherein the end faces of the discharge ports of the nozzles located inside the outermost nozzles constituting the multi-nozzle are flush with the end faces of the discharge ports of the outermost nozzle. A method for producing seamless capsule particles. 3. The thickness of a nozzle inside the outermost nozzle constituting the multiple nozzle is one of the inner diameter of the nozzle.
The method for producing seamless capsule particles according to claim 1 or 2, wherein the content is 30% to 30%. 4. An end face of a discharge port of a nozzle located inside the outermost nozzle is within the end face of the discharge port of the outermost nozzle within a range of not more than twice the inner diameter of the outermost nozzle. Item 5. The method for producing seamless capsule particles according to any one of Items 1 to 3. 5. The multi-nozzle is composed of three or more nozzles, and each nozzle constituting the multi-nozzle is successively depressed from the end face of the discharge port of the outermost nozzle toward the center of the multi-nozzle. The method for producing seamless capsule particles according to claim 1, wherein the capsule particles are formed. 6. The method for producing seamless capsule particles according to claim 1, wherein an interfacial tension of a liquid-liquid surface between adjacent liquids discharged from each nozzle is 20 mN / m or less.