JP5000095B2 - Method for producing organic crystal particles - Google Patents

Description

  The present invention relates to a method for producing organic crystal particles. More specifically, the present invention relates to a method for producing organic crystal particles suitably used as a raw material for cosmetics, daily necessaries such as shampoos, rinses and soaps, and paints and inks.

  Organic crystal particles exhibit various colors and gloss by changing their particle size and shape, so they are used as cosmetics, daily necessaries such as shampoos, rinses and soaps, as well as paints and inks.

  Here, in order to mix organic crystal particles into cosmetics and the like, it is required that the organic solvent and the like be reduced as much as possible for hygiene purposes. Therefore, the manufacturing method which does not use an organic solvent etc. is preferable.

As a method for obtaining particles of an organic compound without using an organic solvent or the like, a method of dissolving and crystallizing in supercritical carbon dioxide is known (for example, see Patent Document 1).
JP-A-6-24787

  Patent Document 1 describes a method of crystallizing 4-isopropyl-5-methylphenol using supercritical carbon dioxide. However, in this method, since the organic compound is dissolved in supercritical carbon dioxide, the type and amount of the organic compound that can be treated are limited by the solubility of the organic compound. The amount of crystallization obtained also in Patent Document 1 is less than 0.01 (g crystals / dissolution tank mL).

  Therefore, the present invention provides a method for producing organic crystal particles that can efficiently produce organic crystal particles that are fine, excellent in slipperiness, touch, etc. over a wide range of organic compounds, and that substantially does not require an organic solvent. The issue is to provide.

That is, the gist of the present invention is as follows.
(1) filling a pressure-resistant container with a low-molecular crystalline organic compound having a polar group;
(2) injecting a fluid into the pressure vessel to bring the fluid into a subcritical or supercritical state and melting the organic compound filled in step (1); and (3) cooling and / or cooling the inside of the pressure vessel. Alternatively, the present invention relates to a method for producing organic crystal particles, including a step of solidifying the organic compound melted in step (2) to form organic crystal particles under reduced pressure.

  According to the method for producing organic crystal particles of the present invention, dry organic crystal particles excellent in slipperiness, touch, etc., which are suitably used as a raw material for cosmetics, daily necessaries such as shampoos, rinses, soaps, and paints and inks. Can be efficiently manufactured.

The method for producing organic crystal particles of the present invention comprises:
(1) filling a pressure-resistant container with a low-molecular crystalline organic compound having a polar group;
(2) injecting a fluid into the pressure vessel to bring the fluid into a subcritical or supercritical state and melting the organic compound filled in step (1); and (3) cooling and / or cooling the pressure vessel. The process includes the step of solidifying the organic compound melted in step (2) to form organic crystal particles under reduced pressure, and the operation of melting a predetermined organic compound in a subcritical or supercritical fluid. One feature is to do.

  In this operation, the predetermined organic compound is not dissolved in the predetermined fluid, that is, not dissolved in the predetermined fluid, but is present in the predetermined fluid in a state where a part of the compound is dissolved.

The organic compound used in the present invention is a low-molecular crystalline organic compound having a polar group. In this specification, a crystalline organic compound refers to an organic compound having a crystal structure. In the present specification, the polar group means a substituent having a high affinity for a polar liquid, that is, a liquid in which a molecule has an electric dipole. Examples of polar groups include, but are not limited to, —OH, —COOH, —COO—, —CO—, —O—, —NH ₂ , —NH—, —CON— and the like. In the present specification, a low molecule means a molecule less than a polymer, that is, a molecule having a weight average molecular weight of less than 10,000, preferably a molecule of 50 to 5000, more preferably a molecule of 100 to 1000. Here, the weight average molecular weight can be measured by gel filtration chromatography. Examples of the organic compound include amphiphilic compounds such as alcohols such as 1-octadecanol, ethers such as distearyl ether, esters such as ethylene glycol distearate, sphingolipid E (pharmaceutical name: And sphingolipids such as N- (hexadecyloxyhydroxypropyl) -N-hydroxyethylhexadecanamide). These organic compounds can be used alone or in admixture of two or more. In addition, as the shape at the time of using the said organic compound as a raw material, a lump shape, a granule, the melted liquid etc. are mentioned, for example, A granule is especially preferable.

《Filling process》
In the step (1), a low molecular crystalline organic compound having a polar group is filled in a pressure resistant container.

  The pressure vessel used in the present invention is not particularly limited as long as it is a closed system, can withstand the temperature and pressure to be used, and has an exhaust mechanism for performing a decompression operation. For example, a known container made of stainless steel or the like is used. Moreover, what was equipped with the stirring mechanism for stirring the contents is preferable.

  The filling amount of the organic compound in the pressure vessel may be larger than the solubility in the fluid that has been changed to the supercritical state or the subcritical state in the step (3), but the upper limit is 10,000 times the solubility from the viewpoint of suppressing aggregation. The following is preferable, 1000 times or less is more preferable, and 100 times or less is more preferable.

  Further, from the viewpoint of improving the dispersibility of the organic compound in the fluid, a dispersion aid may be used. Examples of the dispersion aid include a polymer dispersant. These dispersing aids can be used alone or in admixture of two or more. The filling amount of the dispersion aid into the pressure vessel is not particularly limited as long as it can improve the dispersibility of the organic compound, but is preferably 50 parts by weight or less, more preferably 20 parts by weight or less with respect to 100 parts by weight of the organic compound. More preferably, it is 10 parts by weight or less.

  When the predetermined amount of the organic compound is filled in the pressure vessel, the pressure vessel is sealed.

<Melting process>
In the step (2), a fluid is injected into the pressure vessel, the fluid is brought into a subcritical or supercritical state, and the organic compound is melted. Here, the subcritical state refers to a state where the temperature is equal to or higher than the critical temperature of the fluid, or the pressure is equal to or higher than the critical pressure of the fluid, and the supercritical state refers to the critical temperature of the fluid and both the temperature and the pressure. A state that is above the critical pressure. For example, when the fluid is carbon dioxide, the subcritical state means a state where the temperature is 31.1 ° C. or higher and the pressure is less than 7.38 MPa, or the temperature is lower than 31.1 ° C. and the pressure is 7.38 MPa or higher. The critical state is a state where the temperature is 31.1 ° C. or higher and the pressure is 7.38 MPa or higher. The range of the temperature and pressure of the fluid in the subcritical or supercritical state is not particularly limited because it varies depending on the fluid used. In the case where carbon dioxide is used as a fluid as described above, the condition setting for setting the subcritical or supercritical state may be performed with reference to a phase diagram (temperature-pressure curve) of carbon dioxide (for example, , "Thermal Calculation Handbook" (Japan Management Association), page Db14, Table 22).

  The fluid used in the present invention is not particularly limited as long as it is a fluid that becomes a supercritical or subcritical state in the step (2), and examples thereof include carbon dioxide, water, nitrogen, methane, ethane, methanol, and ethanol. Among these, carbon dioxide is preferable from the viewpoints that the critical conditions are mild, nonflammable, nontoxic and inexpensive.

  As a method for bringing the fluid into a subcritical or supercritical state, for example, the pressure vessel is heated to a predetermined temperature, and then the fluid is injected into the vessel using a high pressure pump or the like to increase the pressure in the vessel. A method of injecting a fluid into a pressure vessel using a high-pressure pump or the like to increase the pressure in the vessel, and subsequently raising the temperature of the vessel to a predetermined temperature, or injecting a fluid into the pressure-resistant vessel using a high-pressure pump or the like And raising the pressure in the container and simultaneously raising the temperature of the container to a predetermined temperature.

  In this specification, the term “melting” refers to a state that occurs in an organic compound when the temperature of a subcritical or supercritical fluid is equal to or higher than the melting point of the organic compound at a subcritical or supercritical pressure. The melting of the organic compound can be visually confirmed by, for example, a meltability test using a high-pressure cell with an observation window.

  In the step (2), the weight ratio of the amount of the organic compound melted in the fluid to the amount of the organic compound dissolved in the fluid (melting amount / dissolving amount) is determined by crystallization from the melt. From the viewpoint of giving priority, it is preferably 0.1 or more, more preferably 0.1 to 100000, still more preferably 1 to 10000, and even more preferably 10 to 1000.

  In the step (2), it is preferable to disperse the molten organic compound for the purpose of suppressing aggregation and controlling the particle size. In this specification, dispersion refers to a state in which molten organic compounds are dispersed as particles in a subcritical or supercritical fluid. The dispersion of the organic compound can be visually confirmed by, for example, a dispersibility test using a high-pressure cell with an observation window. Examples of the dispersion method include application of mechanical dispersion force such as stirring, addition of the dispersion aid, and the like. In addition, when dispersing by stirring, by changing the rotation speed of stirring, the shape of the stirring blade, etc., when using a dispersion aid, by changing the type or amount of the dispersion aid, Can be controlled. The time of dispersion may be immediately after adjusting the temperature and pressure to predetermined conditions as described above, or may be performed during the adjustment.

《Solidification process》
In the step (3), the pressure resistant vessel is cooled and / or decompressed to solidify the molten organic compound to form organic crystal particles.

  The temperature after cooling is less than the melting point of the organic compound at atmospheric pressure. The cooling method and the cooling time are not particularly limited. In addition, it is preferable to perform cooling, stirring the contents in a container. By stirring, the size of the obtained organic crystal particles can be reduced, and it becomes easy to produce particles having a uniform particle size distribution. The shape, rotation speed, and the like of the stirring blade can be appropriately determined according to the container to be used.

  The decompression can be performed by discharging the fluid from the pressure vessel. In addition, it is preferable to carry out pressure reduction, stirring the contents in a pressure vessel like cooling. Moreover, you may perform pressure reduction simultaneously with cooling. Further, the decompression may be performed in one stage, in multiple stages, or may be performed by discharging organic crystal particles together with the fluid as will be described later.

  The organic crystal particles may be recovered by reducing the pressure inside the pressure vessel to atmospheric pressure, then opening the pressure vessel and collecting the organic crystal particles from within the vessel, adjusting the fluid discharge rate from the pressure vessel, The organic crystal particles may be discharged to the outside of the pressure vessel and recovered together with the discharge of. In the method of collecting outside the pressure vessel, aggregation can be reduced, and the particle size can be changed depending on the temperature and pressure conditions in the vessel when discharging outside the vessel. Furthermore, the contents can be continuously discharged by introducing the fluid into the container simultaneously with the discharge of the fluid and the organic crystal particles to the outside of the pressure resistant container. The recovered organic crystal particles can be further crushed and used.

  Thus, desired organic crystal particles can be obtained. The shape of the organic crystal particles is not particularly limited, but plate-like particles are preferable. “Plate-like particles” refers to those having a ratio of the minor axis to the thickness (minor axis / thickness) of 2 or more. The ratio is preferably 3 or more, more preferably 5 or more, and still more preferably 10 or more. The upper limit is usually about 1000.

  The short diameter of the organic plate-like particles is not particularly limited, but is preferably 0.1 to 2000 μm, more preferably 0.1 to 400 μm, and still more preferably 0.1 to 80 μm. On the other hand, the major axis is not particularly limited, but is preferably 0.1 to 3000 μm, more preferably 0.1 to 500 μm, and still more preferably 0.1 to 100 μm. The minor axis and the major axis can be measured based on, for example, a scanning electron microscope (SEM) photograph of organic plate-like particles. In the present specification, the minor axis means the interval when the interval between the parallel lines is minimized when the image of the organic plate-like particles in the SEM photograph is sandwiched between two parallel lines, while the major axis is Means the interval between the parallel lines when the organic plate-like particle image is sandwiched between two parallel lines in a direction perpendicular to the parallel lines when the minor axis is defined.

  The organic crystal particles obtained by the production method of the present invention can be suitably used as a raw material for cosmetics, daily necessities such as shampoos, rinses and soaps, and paints and inks.

  An example of the apparatus used in the following Examples 1-3 and Comparative Examples 1-2 is shown in FIG. The apparatus includes a cylinder 1, a filter 2, a cooling unit 3, a supply pump 4, a check valve 5, a heater 6, a stirring blade 7, a pressure vessel 8, a motor M, a valve V-1, an exhaust valve V-2, and a pressure. A total P-1 is provided. The structural units of the apparatus are arranged in a positional relationship as shown in FIG. 1 and are connected via respective pipes.

Example 1
Sphingolipid E (manufactured by Kao Corporation, N- (hexadecyloxyhydroxypropyl) -N-hydroxyethylhexadecanamide) (10 g) was filled in a pressure vessel (100 mL) 8 and sealed. Carbon dioxide was supplied from the carbon dioxide cylinder 1 to the pressure vessel 8 and further heated to adjust the inside of the tank to 85 ° C. and 30 MPa, and held for 120 minutes. The amount of sphingolipid E filled corresponds to about 170 times the solubility of sphingolipid E under these conditions.

  Subsequently, the inside of the pressure vessel 8 was cooled to 50 ° C. The pressure after cooling was 16 MPa. Thereafter, carbon dioxide was gradually discharged from the exhaust valve V-2, and the pressure in the pressure vessel 8 was reduced from 16 MPa to atmospheric pressure. During the decompression step, the temperature in the pressure vessel 8 was maintained at 45 ° C. After reducing the pressure to atmospheric pressure, the pressure vessel 8 was opened, and organic crystal particles were collected from the inside of the vessel.

  The obtained organic crystal particles were observed by SEM (manufactured by Keyence Corporation), and a micrograph (magnification: 2000 times) of the largest one in the visual field is shown in FIG. It can be seen from the photograph shown in FIG. 2 that the obtained organic crystal particles are plate-like particles having a major axis of 60 μm and a minor axis of 10 μm. The organic crystal particles were dried and excellent in slipperiness and feel.

Example 2
1-octadecanol (manufactured by Sigma-Aldrich Japan) (5.0 g) was filled in a pressure vessel (100 mL) 8 and sealed. By supplying carbon dioxide from the carbon dioxide cylinder 1 to the pressure vessel 8 and further raising the temperature, the inside of the tank is adjusted to 60 ° C. and 30 MPa, and the contents are held for 10 minutes while stirring the contents at 1200 rpm by the stirring blade 7. . At this time, it was observed that 1-octadecanol was dispersed and clouded. The amount of 1-octadecanol charged corresponds to about 25 times the solubility of 1-octadecanol under these conditions.

  Subsequently, the pressure vessel 8 was cooled to 45 ° C. while stirring was maintained at 1200 rpm. The pressure after cooling was 23 MPa. Thereafter, carbon dioxide was gradually discharged from the exhaust valve V-2 while stirring was maintained at 1200 rpm, and the pressure in the pressure vessel 8 was reduced from 23 MPa to atmospheric pressure. During the decompression step, the temperature in the pressure vessel 8 was maintained at 45 ° C. After reducing the pressure to atmospheric pressure, the pressure vessel 8 was opened, and organic crystal particles were collected from the inside of the vessel.

  The obtained organic crystal particles were observed with SEM (manufactured by Keyence Corporation), and a photomicrograph (magnification: 2000 times) of the largest in the field of view is shown in FIG. From the photograph shown in FIG. 3, it can be seen that the obtained organic crystal particles are plate-like particles having a major axis of 35 μm and a minor axis of 30 μm. The organic crystal particles were dried and excellent in slipperiness and feel.

Example 3
Sphingolipid E (manufactured by Kao Corporation, N- (hexadecyloxyhydroxypropyl) -N-hydroxyethylhexadecanamide) (3.0 g) was filled in a pressure vessel (100 mL) 8 and sealed. By supplying carbon dioxide from the carbon dioxide cylinder 1 to the pressure vessel 8 and further raising the temperature, the inside of the tank is adjusted to 85 ° C. and 27 MPa, and the contents are held for 10 minutes while being stirred at 1400 rpm by the stirring blade 7. . At this time, it was observed that the sphingolipid E was dispersed and clouded. The amount of sphingolipid E filled corresponds to about 50 times the solubility of sphingolipid E under these conditions.

  Subsequently, the pressure vessel 8 was cooled to 55 ° C. while stirring was maintained at 1400 rpm. The pressure after cooling was 23 MPa. Thereafter, carbon dioxide was gradually discharged from the exhaust valve V-2 while maintaining stirring at 1400 rpm, and the pressure in the pressure-resistant vessel 8 was reduced from 23 MPa to atmospheric pressure. During the decompression step, the temperature in the pressure vessel 8 was maintained at 45 ° C. After reducing the pressure to atmospheric pressure, the pressure vessel 8 was opened, and organic crystal particles were collected from the inside of the vessel.

  The obtained organic crystal particles were observed with SEM (manufactured by Keyence Corporation), and a photomicrograph (magnification: 2000 times) of the largest one in the field of view is shown in FIG. From the photograph shown in FIG. 4, it can be seen that the obtained organic crystal particles are plate-like particles having a major axis of 20 μm and a minor axis of 5 μm. The organic crystal particles were dried and excellent in slipperiness and feel.

Example 4
Sphingolipid E (manufactured by Kao Corporation, N- (hexadecyloxyhydroxypropyl) -N-hydroxyethylhexadecanamide) (15 g) was filled in a pressure vessel (100 mL) 8 and sealed. By supplying carbon dioxide from the carbon dioxide cylinder 1 to the pressure vessel 8 and further raising the temperature, the inside of the tank is adjusted to 85 ° C. and 7 MPa, and the contents are held for 60 minutes while being stirred at 110 rpm by the stirring blade 7. . At this time, it was observed that the sphingolipid E was dispersed and clouded. The amount of sphingolipid E filled corresponds to about 250 times the solubility of sphingolipid E under these conditions.

  Subsequently, stirring was stopped and the inside of the pressure vessel 8 was cooled to 50 ° C. The pressure after cooling was 5.8 MPa. Thereafter, carbon dioxide was gradually discharged from the exhaust valve V-2, and the pressure in the pressure vessel 8 was reduced from 5.8 MPa to atmospheric pressure. During the decompression step, the temperature in the pressure vessel 8 was maintained at 45 ° C. After reducing the pressure to atmospheric pressure, the pressure vessel 8 was opened, and organic crystal particles were collected from the inside of the vessel.

  The obtained organic crystal particles were observed with SEM (manufactured by Keyence Corporation), and a photomicrograph (magnification: 2000 times) is shown in FIG. From the photograph shown in FIG. 5, it can be seen that the obtained organic crystal particles are the largest in the field of view and are plate-like particles having a major axis of 15 μm and a minor axis of 8 μm. The organic crystal particles were dried and excellent in slipperiness and feel.

Comparative Example 1
1-Octadecanol (manufactured by Sigma-Aldrich Japan) (5.0 g) and ion-exchanged water (80 g) were filled in a glass container (100 mL) and sealed. While stirring the contents with a magnetic stirrer, the temperature was raised to 65 ° C. and held for 10 minutes. During stirring, it was observed that 1-octadecanol was dispersed and clouded.

  Subsequently, the glass container was cooled in a 20 ° C. water bath while stirring was maintained. After cooling, 1-octadecanol aggregated into a lump and crystal particles could not be obtained.

Comparative Example 2
Sphingolipid E (3.0 g) and ion-exchanged water (80 g) were filled in a glass container (100 mL) and sealed. While stirring the contents with a magnetic stirrer, the temperature was raised to 85 ° C. and held for 10 minutes. During stirring, sphingolipid E was dispersed and clouded.

  Subsequently, the glass container was cooled in a 20 ° C. water bath while stirring was maintained. After cooling, sphingolipid E aggregated into a lump and crystal particles could not be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the high quality organic crystal particle which can be used conveniently for cosmetics, cosmetics, a coating material, ink etc. can be provided, for example.

It is a schematic explanatory drawing which shows an example of the apparatus which can be used in this invention. 2 is a photomicrograph (2000 magnifications) of organic crystal particles obtained in Example 1. 2 is a photomicrograph (2000 magnifications) of organic crystal particles obtained in Example 2. 2 is a photomicrograph (2000 magnifications) of organic crystal particles obtained in Example 3. 2 is a photomicrograph (2000 magnifications) of organic crystal particles obtained in Example 4.

Explanation of symbols

1 cylinder 2 filter 3 cooling unit 4 supply pump 5 check valve 6 heater 7 stirring blade 8 pressure vessel M motor V-1 valve V-2 exhaust valve P-1 pressure gauge

Claims (4)

(1) filling a pressure-resistant container with a low-molecular crystalline organic compound having a polar group;
(2) A fluid made of carbon dioxide is injected into the pressure vessel to bring the fluid into a subcritical or supercritical state, and heated to a temperature equal to or higher than the melting point of the organic compound filled in step (1). And (3) cooling the inside of the pressure vessel and solidifying the molten organic compound in step (2) to form organic crystal particles, The method for producing organic crystal particles, wherein the low-molecular crystalline organic compound having a polar group is 1-octadecanol or N- (hexadecyloxyhydroxypropyl) -N-hydroxyethylhexadecanamide . In step (2), the weight ratio of the amount of the organic compound dissolved in the amount and the fluid of an organic compound which is melted in a fluid (molten amount / amount dissolved) is 10 to 1000, according to claim 1 Symbol The manufacturing method described. The production method according to claim 1, wherein the organic crystal particles are organic plate-like particles. The production method according to claim 3, wherein the organic plate-like particles have a minor axis of 0.1 to 400 μm and a major axis of 0.1 to 500 μm.