Spraying device and spraying method

Abstract

The present invention provides a spraying apparatus and spraying method that efficiently forms a fine mist of undiluted liquid in a simple manner. [Solution] The spraying device of the present invention includes a pressure-resistant container and a spray unit connected to the pressure-resistant container. The pressure-resistant container contains a mixed liquid obtained by mixing a stock solution and liquid carbon dioxide. The spray unit sprays the mixed liquid in a mist form, and the temperature range of the pressure-resistant container is above the triple point temperature of carbon dioxide and below the critical temperature.

Description

Technical Field

[0001] The present invention relates to a spraying device and a spraying method.

Background Art

[0002] Spraying devices are used in products in a wide range of fields such as hair care styling agents, skin care agents, cooling agents, fragrances, cleaning agents, various coating agents, agricultural chemicals, and lubricating oils for mechanical cutting. Conventional spraying devices use compressed gas to pressurize the stock solution and spray it in a fine mist. Examples of compressed gas include air, nitrogen, carbon dioxide gas, nitrous oxide, LP gas, etc. As the stock solution, a wide variety of substances are used depending on the field of use and the purpose of use. For example, there is an example of spraying a stock solution containing a skin care agent composition or a cooling agent composition onto the human body (for example, Patent Document 1), and there is also an example of spraying lubricating oil onto the workpiece in the cutting of metal materials (for example, Patent Document 2).

[0003] On the other hand, a spraying method and a spraying device for injecting a mixture of a coating composition and supercritical carbon dioxide fluid using supercritical carbon dioxide fluid have been disclosed (for example, Patent Document 3).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] Atomizers using compressed gas, such as those described in Patent Documents 1 and 2 above, have potential for improvement in forming a fine mist. However, when using compressed air, compressed nitrogen, or compressed carbon dioxide, there are challenges in handling the high-pressure gas, and when using LP gas as a flammable gas, there are safety concerns. Atomizers using supercritical carbon dioxide fluid, such as those described in Patent Document 3 above, have the problem of being complex and expensive because they use high-pressure containers that exceed the critical pressure of carbon dioxide.

[0006] The present invention has been made in view of the above problems, and aims to provide a spraying device and spraying method that can efficiently atomize a stock solution, which is maintained in a liquid state of carbon dioxide and is well mixed (e.g., dissolved or dispersed) with liquid carbon dioxide within a temperature and pressure range, into a fine mist using a simple method. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides the following means.

[0008] [1] A spraying device comprising a pressure vessel and a spray unit connected to the pressure vessel, The pressure vessel contains a mixed liquid obtained by mixing the stock solution and liquid carbon dioxide. The mixture is sprayed in a mist form from the spray nozzle. A spraying device in which the temperature range of the pressure vessel is above the triple point temperature of carbon dioxide and below the critical temperature. [2] The spraying apparatus according to [1], wherein the carbon dioxide in the pressure vessel is in a subcritical or high-pressure liquid state. [3] The spraying apparatus according to [1] or [2], wherein the pressure range in the pressure vessel is 0.1 MPa or more and 50 MPa or less, and the temperature range in the pressure vessel is -57°C or more and 31°C or less. [4] The spraying device according to any one of [1] to [3], wherein the maximum operating pressure of the pressure vessel is 2 MPa or more and less than the critical pressure. [5] The spraying device according to any one of [1] to [4], wherein the pressure range of the pressure vessel exceeds the triple point pressure of carbon dioxide and is less than the critical pressure. [6] The spraying apparatus according to any one of [1] to [5], wherein the pressure vessel further contains carbon dioxide gas and is in a gas-liquid equilibrium state of carbon dioxide. [7] The injection unit and the pressure vessel are directly connected, A spraying device according to any one of [1] to [6], wherein the mixed liquid is supplied from the pressure-resistant container to the spraying section. [8] Between the injection unit and the pressure vessel there is further piping, A spraying device according to any one of [1] to [7], wherein the mixed liquid is supplied from the pressure vessel to the spraying section through the aforementioned piping. [9] The pressure vessel has a mixed liquid outlet for introducing the mixed liquid into the injection section and a liquid carbon dioxide supply port for supplying the liquid carbon dioxide to the pressure vessel, A spraying device according to any one of [1] to [8] that supplies liquid carbon dioxide to the pressure-resistant container through the liquid carbon dioxide supply port.

[10] The pressure vessel has a mixed liquid outlet for introducing the mixed liquid into the injection section, a liquid carbon dioxide supply port for supplying the liquid carbon dioxide, and a stock liquid supply port for supplying the stock liquid, The liquid carbon dioxide is supplied to the pressure vessel through the liquid carbon dioxide supply port. A spraying device according to any one of [1] to [9] that supplies the stock solution to the pressure-resistant container through the stock solution supply port.

[11] The spraying apparatus according to any one of [1] to

[10] , wherein the stock solution is dissolved or dispersed in the liquid carbon dioxide in the mixed solution.

[12] The spraying apparatus according to any one of [1] to

[11] , wherein the stock solution is at least one selected from the group consisting of lemon oil, essential oil components, algal oil, paint, etc.

[13] The spraying apparatus according to any one of [1] to

[12] , wherein the mass ratio of the stock solution to the liquid carbon dioxide (stock solution / liquid carbon dioxide) in the pressure vessel is 0.01 to 0.99.

[14] The spraying apparatus according to any one of [1] to

[13] , wherein the droplet size of the atomized stock solution sprayed from the spraying unit is 0.1 nm or more and 0.5 μm.

[15] A mixing step in which the stock solution and liquid carbon dioxide are mixed inside the pressure vessel, A spraying method comprising a spraying step of spraying the mixed liquid obtained in the mixing step in a mist form, A spraying method wherein the temperature range of the mixed liquid is above the triple point temperature of carbon dioxide and below the critical temperature.

[16] The spraying method according to

[15] , wherein the liquid carbon dioxide is in a subcritical state or a high-pressure liquid.

[17] The spraying method according to

[15] or

[16] , wherein the pressure range of the mixed liquid is 0.1 MPa or more and 50 MPa or less, and the temperature range of the pressure-resistant container is -57°C or more and 31°C or less.

[18] The spraying method according to any one of

[15] to

[17] , further comprising a liquid carbon dioxide supply step of supplying the liquid carbon dioxide.

[19] A spraying method according to any one of

[15] to

[18] , further comprising a liquid carbon dioxide supply step for supplying the liquid carbon dioxide and a stock solution supply step for supplying the stock solution.

[20] The spraying method according to any one of

[15] to

[19] , wherein in the mixed liquid obtained in the mixing step, the stock solution is dissolved or dispersed in the liquid carbon dioxide.

[21] The spraying method according to any one of

[15] to

[20] , wherein the stock solution is at least one selected from the group consisting of lemon oil, essential oil components, algal oil, and paint.

[22] The spraying method according to any one of

[15] to

[21] , wherein in the pressure vessel, the mass ratio of the stock solution to liquid carbon dioxide (stock solution / liquid carbon dioxide) is 0.01 to 0.99.

[23] The spraying method according to any one of

[15] to

[22] , wherein the droplet size of the atomized stock solution sprayed in the spraying step is 0.10 nm or more and 0.50 μm. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a spraying device and a spraying method that can efficiently form a fine mist-like stock solution in a simple manner.

Brief Description of the Drawings

[0010] [Figure 1] FIG. 1 is a schematic diagram showing the spraying device of the first embodiment. [Figure 2] FIG. 2 is a schematic diagram showing another embodiment of the spraying device of the first embodiment. [Figure 3] FIG. 3 is a schematic diagram showing the spraying device of the second embodiment. [[ID=十五]] [Figure 4] FIG. 4 is a schematic diagram showing the spraying device of the third embodiment. [Figure 5] FIG. 5 is a diagram showing the relationship between the amount (g) of sprayed limonene and the amount (L) of carbon dioxide gas in Example 1 and Comparative Example 1. [Figure 6] FIG. 6 is a phase diagram of the two components of carbon dioxide and limonene.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, this embodiment will be described in detail with appropriate reference to the drawings. The drawings used in the following description may show the characteristic parts enlarged for the sake of clarity of the features of the present invention, and the dimensional ratios of each component may be different from the actual ones. The materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited thereto, and can be appropriately changed and implemented within the scope of not changing the gist thereof. <\(0000106\)><\(0000107\)>(Spraying Device)<\(0000108\)>[First Embodiment]<\(0000109\)>The spraying device of the first embodiment includes a pressure vessel 4 and a spray unit 2 connected to the pressure vessel 4, as shown in Figure 1. The pressure vessel 4 contains a mixed liquid 6 obtained by mixing a stock solution and liquid carbon dioxide. The spray unit 2 sprays the mixed liquid in a mist form. The temperature range inside the pressure vessel 4 is above the triple point temperature of carbon dioxide and below the critical temperature. The carbon dioxide in the pressure vessel may be in a subcritical or high-pressure liquid state, and it is preferable that the pressure range in the pressure vessel is 0.1 MPa or more and 50 MPa or less, and the temperature range in the pressure vessel is 57°C or more and 31°C or less. The spraying device of this embodiment may further include means for controlling the temperature or pressure of the pressure vessel to within the above temperature and pressure ranges. A pipe (not shown) may be further provided between the spraying unit and the pressure vessel, and the mixed liquid may be supplied from the pressure vessel to the spraying unit through the pipe. The spraying device of this embodiment may be configured such that the pressure vessel 4 is filled with the mixed liquid 6, as shown in the spraying device 1 of Figure 1, or it may be configured such that the pressure vessel 40 contains the mixed liquid 60 and carbon dioxide gas 80, as shown in the spraying device 10 of Figure 2. As shown in the spraying device 10 in Figure 2, when a mixture 60 and carbon dioxide 80 are present, the amount of carbon dioxide 80 (volume ratio in the pressure vessel 4) may be 1 volume% or more, 5 volume% or more, 10 volume% or more, or 30 volume% or more. It may also be 80 volume% or less, 60 volume% or less, or 40 volume% or less.

[0013] [Pressure vessel] The mixing container may have a mixing outlet for introducing the mixing liquid into the injection section and a liquid carbon dioxide supply port for supplying the liquid carbon dioxide to the pressure-resistant container. The mixed liquid outlet and the liquid carbon dioxide supply port may be a single opening formed at the same location in the mixing container. In this case, liquid carbon dioxide can first be supplied to the pressure vessel to prepare the mixed liquid of the stock solution and liquid carbon dioxide, and then the mixed liquid can be supplied to the injection unit from the same opening. Alternatively, the mixed liquid outlet and the liquid carbon dioxide supply port may be two openings formed at different locations in the mixing container. In this case, liquid carbon dioxide can first be supplied to the pressure vessel through the liquid carbon dioxide supply port to prepare the mixed liquid of the stock solution and liquid carbon dioxide, and then the mixed liquid can be supplied to the injection unit from the mixed liquid outlet. Furthermore, the supply of liquid carbon dioxide and the supply of the mixed liquid may be performed alternately in stages, such as in a batch system, or they may be supplied simultaneously, such as in a continuous system.

[0014] The carbon dioxide in the pressure vessel may be in a subcritical or high-pressure liquid state. Furthermore, the pressure range in the pressure vessel may be between 0.1 MPa and 50 MPa, and the temperature range in the pressure vessel may be between -57°C and 31°C. As long as the carbon dioxide is maintained in a liquid state in the pressure vessel, the pressure range and temperature range can be appropriately selected depending on the application. For example, if there is a pressure limit for the pressure vessel, the pressure range of the pressure vessel may be 0.55 MPa or more and 4.0 MPa or less, and the temperature range may be -57°C or more and 0°C or less, or the pressure range may be 0.55 MPa or more and 2.0 MPa or less, and the temperature range may be -57°C or more and -20°C or less, or furthermore, the pressure range may be 0.55 MPa or more and 1.0 MPa or less, and the temperature range may be -57°C or more and -40°C or less. A known method can be used to control the temperature of the pressure vessel at a low temperature. For example, the pressure vessel may have walls with an insulating structure. Also, for example, when controlling to 0°C or below, the temperature of the pressure vessel can be controlled to 0°C or below using a refrigerant.

[0015] Furthermore, for example, if the temperature range of the pressure vessel is near room temperature, the pressure range in the pressure vessel may be 4.2 MPa or more and 7.0 MPa or less, and the temperature range in the pressure vessel may be 10°C or more and 30°C or less, or the pressure range may be 5.0 MPa or more and 6.5 MPa or less, and the temperature range may be 15°C or more and 25°C or less, or the pressure range may be 5.5 MPa or more and 6.5 MPa or less, and the temperature range may be 20°C or more and 25°C or less. For example, in the embodiment described later, a liquefied carbon dioxide cylinder was used as the liquid carbon dioxide supply source. The temperature range of the pressure-resistant container was set to room temperature of 25°C and controlled to the same pressure as the liquefied carbon dioxide cylinder pressure of 6.3 MPa (25°C). A mixture was prepared by mixing the undiluted limonene (the main component of lemon oil) in the container with liquid carbon dioxide.

[0016] The temperature range and pressure range of the pressure vessel may be the same or different in the mixed liquid preparation step and the mixed liquid supply step, respectively. For example, in the mixed liquid preparation step, the temperature range may be controlled to room temperature from the viewpoint of efficiently mixing the stock solution and liquid carbon dioxide, while in the mixed liquid supply step, the temperature range may be controlled to 0°C or below.

[0017] The pressure vessel may further have a concentrate supply port for supplying the concentrate. The concentrate can be supplied to the pressure vessel through the concentrate supply port.

[0018] The pressure vessel may have a pressure-resistant structure that can withstand internal pressures at least above the critical pressure of carbon dioxide. From the viewpoint of reducing the cost of the device while achieving the objectives of the present invention, it is sufficient for the pressure vessel to have a pressure-resistant structure that can withstand internal pressures below the critical pressure of carbon dioxide, and it is not necessary for it to have a pressure-resistant structure that can withstand pressures above the critical pressure of carbon dioxide. For example, the maximum operating pressure may be 7 MPa or less, or 6.5 MPa or less. Alternatively, in usage conditions where the above temperature range is a low temperature range (0°C or below, or -20°C or below), the maximum operating pressure may be 5.0 MPa or less, 4.0 MPa or less, or 3.0 MPa or less. Furthermore, the above maximum operating pressure may be, for example, 1.0 MPa or more, or 2.0 MPa or more. Examples of the pressure vessel include pressure vessels having the above-mentioned various maximum operating pressures. The pressure vessel structure having the above-mentioned maximum operating pressure can be any known structure and is not particularly limited. Examples of the pressure vessel include pressure vessels having pressure reducing valves and safety valves that maintain the various maximum operating pressures mentioned above.

[0019] <Mixed liquid> Examples of the mixed solution include a solution obtained by dissolving the stock solution in liquid carbon dioxide, and a dispersion obtained by dispersing the stock solution in liquid carbon dioxide. The stock solution contained in the mixture may be soluble in liquid carbon dioxide, or dispersible in liquid carbon dioxide, and is not particularly limited. Examples of the stock solution include lemon oil, essential oil components, algae oil, lubricating oil for machine cutting, hair care and styling products, skin care products, cooling agents, fragrances, cleaning agents, various coating agents, pesticide compositions, and paints. The stock solution may be lemon oil, essential oil components, algae oil, or paints. In the pressure-resistant vessel, the mass ratio of the undiluted solution to the liquid carbon dioxide (undiluted solution / liquid carbon dioxide) is preferably 0.01 to 0.99.

[0020] [Injection part] The injection unit in this embodiment sprays the mixed liquid introduced from the pressure vessel to form a mist-like mixture, and as the liquid carbon dioxide evaporates, it forms fine mist-like droplets (mist) of the undiluted liquid. The injection unit is a component for discharging the mixed liquid and mainly comprises a nozzle section with discharge holes and a valve mechanism for operating the injection opening and closing. The mixed liquid is discharged from the discharge holes. The number and shape of the discharge holes are not particularly limited. There may be multiple discharge holes. The shape of the discharge holes may be circular, angular, or the like. In this embodiment of the spraying device, when the valve mechanism is opened, the pressure-resistant container is opened. As a result, the inside of the mixing container body and the spraying part or the outside are connected. The mixed liquid is sent to the spraying member and then discharged from the discharge hole. The injection unit may further have an introduction pipe. The mixture can be introduced to the injection unit from the bottom of the pressure vessel using the introduction pipe. In particular, if the pressure vessel contains carbon dioxide gas (sometimes called "carbon dioxide gas") and a mixture, and has a gas phase portion consisting of carbon dioxide gas and a liquid phase portion consisting of the mixture, the pressure of the carbon dioxide gas presses down the liquid surface of the mixture. As a result, the mixture passes through the introduction pipe and is sent to the injection member, and then discharged from the discharge hole.

[0021] The spraying apparatus of this embodiment will be further described using the following examples of the second and third embodiments. The spraying apparatus of this embodiment is not limited to these disclosures. Also, the description of parts that are the same as in the first embodiment will be omitted.

[0022] [Second Embodiment] The spraying device 100 of the second embodiment includes a pressure vessel 14 and a spray unit 12 directly connected to the pressure vessel 14, as shown in Figure 3. The pressure vessel 14 contains a mixed liquid 16 containing a stock solution and liquid carbon dioxide, and carbon dioxide gas 18. The spray unit 12 includes an introduction pipe 12-1, a valve 12-2, a spray nozzle 12-3, and a spray operation unit 12-4. The mixed liquid is introduced into the spray unit 12 from the bottom of the pressure vessel 14 through the introduction pipe 12-1. The valve 12-2 is installed between the introduction pipe 12-1 and the spray nozzle 12-3. The spray operation unit 12-4 is operated to open and close the valve 12-2 and operate the spray. As the spray unit 12 of the spraying device 100 in the second embodiment, for example, a known spray or aerosol spraying mechanism can be used. Furthermore, since a mixed liquid containing liquid carbon dioxide is used, a heating mechanism may be included in the spray unit 12 as needed. The heating mechanism can be, for example, a heating mechanism for a liquid carbon dioxide gas cylinder valve. This is because the temperature near the nozzle may decrease depending on the temperature, pressure, spray volume, spraying frequency, etc. of the pressure-resistant container 14. The pressure vessel 14 may be a pressure vessel with a maximum operating pressure of 7.5 MPa, a pressure vessel with a maximum operating pressure of 7 MPa, or a pressure vessel with a maximum operating pressure of 6.5 MPa. In this case, under normal room temperature conditions (e.g., 25°C), the carbon dioxide contained in the mixture 16 is in the liquid phase, i.e., it is liquid carbon dioxide. Furthermore, the volume ratio of the mixture and carbon dioxide (mixture:carbon dioxide) can be any supply volume ratio as long as it is such that a homogeneous phase state is formed when mixed. In the pressure vessel 14, further safety mechanisms such as a pressure regulating safety valve may be provided. For example, a safety valve with a pressure 0.5 MPa lower than the maximum operating pressure may be set. For example, if a pressure vessel with a maximum operating pressure of 7.5 MPa is used, a safety valve with a pressure of 7 MPa may be provided to prevent an abnormal pressure rise due to temperature rise. In that case, even if the ambient temperature exceeds 30°C, the internal pressure of the pressure vessel 14 will not exceed the critical pressure of carbon dioxide, and carbon dioxide will not become a supercritical fluid. The pressure vessel 14 can maintain its internal temperature at, for example, -20°C or below by using an insulating layer or a cooling mechanism. In this case, a pressure vessel 14 with a maximum operating pressure of 2.5 MPa may be used.

[0023] [Third Embodiment] The spraying device 200 of the third embodiment includes a pressure vessel 24 and an injection unit 22 connected to the pressure vessel 24 through a first pipe 23-1, as shown in Figure 4. The spraying device 200 further includes a liquefied carbon dioxide gas cylinder 25, a valve (V0) 21, a safety valve 27, and a second pipe 23-2. Liquid carbon dioxide is supplied from the liquefied carbon dioxide gas cylinder 25 to the pressure vessel 24 through the second pipe 23-2. The injection unit 22 includes a valve (v1) 22-1, a valve (v2) 22-2, and an injection port 22-3. The liquefied carbon dioxide gas cylinder 25 can be, for example, a commercially available 6.3 MPa pressure liquid carbon dioxide gas cylinder. The liquid carbon dioxide is supplied to the pressure-resistant container 24 to maintain a pressure of 6.3 MPa. The spraying device 200 of the third embodiment can prepare a mixed solution by introducing the stock solution into the pressure-resistant container 24 before supplying liquid carbon dioxide, and then introducing the liquid carbon dioxide. The spraying device 200 of the third embodiment may also have a mechanism (not shown) for supplying the stock solution. In that case, the supply of liquid carbon dioxide and the supply of the stock solution may be performed continuously or intermittently, and the amount of mixed solution sprayed may be replenished. Examples of the aforementioned liquefied carbon dioxide gas cylinders include commercially available liquefied carbon dioxide gas cylinders manufactured by Taiyo Nippon Sanso Corporation and Resonac Corporation. Examples of the first pipe 23-1 and the second pipe 23-2 include metal coils manufactured by Swagelok. Examples of valves (v0)21, (v1)22-1, and (v2)22-2 include needle valves and metering valves manufactured by Swagelok. Examples of the safety valve 27 include safety valves manufactured by JASCO Corporation.

[0024] [Applications of spraying devices] Possible applications of the spraying device of this embodiment include, for example, cosmetic sprays such as foam spray shampoos, fragrance and perfume sprays, deodorizing sprays, spray painting, and flavoring and aromatherapy for food.

[0025] (Spraying method) A spraying method according to one embodiment of the present invention includes the following two steps: (1) A mixing step in which the stock solution and liquid carbon dioxide are mixed. (2) A spraying step in which the mixed liquid obtained in the mixing step is sprayed in a mist. The temperature range of the mixture is above the triple point temperature of carbon dioxide and below the critical temperature. Preferably, the liquid carbon dioxide is in a subcritical state rather than a supercritical state. Preferably, the pressure range of the mixture is 0.1 MPa or more and 50 MPa or less, and the temperature range of the pressure vessel is -57°C or more and 31°C or less.

[0026] The spraying method of this embodiment may further include one or two of the following two steps. (3) Liquid carbon dioxide supply process for supplying liquid carbon dioxide. (4) A stock solution supply step, which involves supplying the stock solution.

[0027] In the spraying method of this embodiment, the terms "stock solution," "mixed solution," "mass ratio of stock solution to liquid carbon dioxide (stock solution / liquid carbon dioxide)," and "droplet size of the atomized stock solution sprayed in the spraying step" have the same meaning as those described in the spraying apparatus of the first to third embodiments described above. The spraying method of this embodiment may also use the spraying apparatus of the first to third embodiments. [Examples]

[0028] (Example 1) Example 1 used the spraying device 200 of the third embodiment shown in Figure 4. 5.8 g of limonene, the main component of lemon oil, was placed in the pressure vessel 24. Liquid carbon dioxide was then supplied to the pressure vessel 24 from a liquefied carbon dioxide gas cylinder to prepare a mixture of limonene and carbon dioxide. The prepared mixture was then sprayed from the nozzle by controlling valves (v1) 22-1 and (v2) 22-2. The amount of limonene sprayed was measured using the measurement method described below, and the flow rate of the sprayed carbon dioxide gas (after evaporation of liquid carbon dioxide) was measured simultaneously. The results are shown in Figure 5. Details of the apparatus, experimental conditions for the injection experiment, and evaluation method are shown below.

[0029] [Spraying device] Liquefied carbon dioxide cylinder: Resonaq Corporation liquefied carbon dioxide cylinder (99.5% purity), pressure at room temperature: 6.3 MPa Pressure vessel 24: EV series manufactured by JASCO Corporation Nozzle 22-3: Swagelok needle valve Valve (v0)21: Swagelok needle valve Valve (v1) 22-1: Swagelok needle valve Valve (v2) 22-2: Swagelok needle valve Safety valve 27: Safety valve manufactured by JASCO Corporation Piping 1 23-1: GL Science 1 / 16 inch stainless steel coil Piping 23-2: GL Science 1 / 16 inch stainless steel coil

[0030] [Experimental conditions for limonene injection experiment] Amount of limonene used: 5.8g Extraction cell (pressure-resistant container 24) internal volume: 50 cm³ 3 Internal temperature of pressure vessel 24: 25℃ Pressure: 6.3 MPa Flow rate: 4 L / min (SATP: standard ambient temperature and pressure)

[0031] [Evaluation Method] <Method for measuring the amount of limonene released> The amount of limonene released was collected using a trap cooled with ice water, and its weight was directly measured using a balance.

[0032] <Method for measuring carbon dioxide flow velocity and flow rate> The flow velocity and flow rate of carbon dioxide were measured using a dry flow meter (Shinagawa DC-2) after the mixture was adjusted to atmospheric pressure.

[0033] (Comparative Example 1) The spray experiment was conducted in the same manner as in Example 1, except that the internal temperature of the pressure vessel 24 was set to 40°C (warm bath). Similar to Example 1, the carbon dioxide flow rate and limonene emission rate were evaluated, and the results are shown in Figure 5.

[0034] (Consideration) As shown in Figure 5, under the temperature and pressure conditions of Example 1 (25°C, 6.3 MPa), carbon dioxide existed as a liquid in the pressure vessel 24, and a mixture of this liquid carbon dioxide and limonene was obtained. In contrast, under the temperature conditions of Comparative Example 1 (40°C), carbon dioxide existed as a supercritical fluid in the pressure vessel 24, and a mixture of this supercritical carbon dioxide fluid and limonene was obtained. As shown in Figure 5, under the temperature and pressure conditions in which liquid carbon dioxide exists, the amount of limonene ejected was dramatically increased compared to that of supercritical carbon dioxide.

[0035] Figure 6 shows the phase diagram of a two-component system of carbon dioxide and limonene. As shown in Figure 6, the phase equilibrium relationship is such that liquid carbon dioxide has a higher mixing ratio with limonene than supercritical carbon dioxide fluid. Under supercritical conditions like those in Comparative Example 1, not only is high-temperature operation required, but at 6.3 MPa, two phases (gas-liquid phase) appear, and high spray efficiency cannot be obtained unless the liquid phase is effectively utilized. On the other hand, under liquid carbon dioxide conditions like those in Example 1 (subcritical conditions), at 6.3 MPa, a homogeneous phase is formed under all compositional conditions, allowing lemon oil of any composition to be discharged (sprayed) all at once. Furthermore, cooling the pressure-resistant cell (pressure-resistant container 24) shifts the phase equilibrium curve to an even lower pressure side, so more efficient spraying can be expected with simpler operation. Also, under experimental conditions below room temperature, the fact that lemon oil is sensitive to heat is an important factor. [Explanation of symbols]

[0036] 1, 10, 100, 200: Spray device 2, 20, 12, 22: Injection part 4, 40, 14, 26: Pressure vessels 6, 60, 16, 26: A mixture containing the undiluted solution and liquid carbon dioxide. 12-3, 22-3: Jet nozzle 12-4: Injection operation part 12-2: Valve 12-1:Introduction tube 18: Carbon dioxide 21: Valve v0 22-1: Valve v1 22-2: Valve v2 23-1: First piping 23-2: Second piping 25: Liquefied carbon dioxide gas cylinder 27: Safety valve

Claims

1. A spraying device comprising a pressure vessel and a spray unit connected to the pressure vessel, The pressure vessel contains a mixed liquid obtained by mixing the stock solution and liquid carbon dioxide. The mixture is sprayed in a mist form from the spray nozzle. A spraying device in which the temperature range of the pressure vessel is above the triple point temperature of carbon dioxide and below the critical temperature.

2. The spraying apparatus according to claim 1, wherein the carbon dioxide in the pressure vessel is in a subcritical or high-pressure liquid state.

3. The spraying apparatus according to claim 1, wherein the pressure range in the pressure vessel is 0.1 MPa or more and 50 MPa or less, and the temperature range in the pressure vessel is -57°C or more and 31°C or less.

4. The spraying apparatus according to claim 1, wherein the maximum operating pressure of the pressure-resistant vessel is 2 MPa or more and less than the critical pressure.

5. The spraying device according to claim 1, wherein the pressure range of the pressure-resistant vessel exceeds the triple point pressure of carbon dioxide and is less than the critical pressure.

6. The spraying apparatus according to claim 1, wherein the pressure vessel may further contain carbon dioxide gas, in which case it is in a gas-liquid equilibrium state of carbon dioxide.

7. The injection unit and the pressure vessel are directly connected. The spraying device according to claim 1, wherein the mixed liquid is supplied from the pressure vessel to the spraying section.

8. There is further piping between the injection unit and the pressure vessel, The spraying device according to claim 1, wherein the mixed liquid is supplied from the pressure vessel to the spraying section through the aforementioned piping.

9. The pressure vessel has a mixed liquid outlet for introducing the mixed liquid into the injection section and a liquid carbon dioxide supply port for supplying the liquid carbon dioxide to the pressure vessel. The spraying device according to claim 1, wherein liquid carbon dioxide is supplied to the pressure-resistant container through the liquid carbon dioxide supply port.

10. The pressure vessel has a mixed liquid outlet for introducing the mixed liquid into the injection section, a liquid carbon dioxide supply port for supplying the liquid carbon dioxide, and a concentrate supply port for supplying the concentrate, The liquid carbon dioxide is supplied to the pressure vessel through the liquid carbon dioxide supply port. The spraying apparatus according to claim 1, wherein the concentrate is supplied to the pressure-resistant container through the concentrate supply port.

11. The spraying apparatus according to claim 1, wherein in the mixed liquid, the stock solution is dissolved or dispersed in the liquid carbon dioxide.

12. The spraying apparatus according to claim 1, wherein the stock solution is at least one selected from the group consisting of lemon oil, essential oil components, algal oil, paint, etc.

13. The spraying apparatus according to claim 1, wherein the mass ratio of the stock solution to the liquid carbon dioxide (stock solution / liquid carbon dioxide) in the pressure-resistant container is 0.01 to 0.

99.

14. The spraying apparatus according to claim 1, wherein the droplet size of the atomized undiluted liquid sprayed from the spraying unit is 0.1 nm or more and 0.5 μm.

15. A mixing step is performed inside the pressure vessel, in which the stock solution and liquid carbon dioxide are mixed. A spraying method comprising a spraying step of spraying the mixed liquid obtained in the mixing step in a mist form, A spraying method wherein the temperature range of the mixed liquid is above the triple point temperature of carbon dioxide and below the critical temperature.

16. The spraying method according to claim 15, wherein the liquid carbon dioxide is in a subcritical state or a high-pressure liquid.

17. The spraying method according to claim 15, wherein the pressure range of the mixed liquid in the pressure-resistant container is 0.1 MPa or more and 50 MPa or less, and the temperature range is -57°C or more and 31°C or less.

18. The spraying method according to claim 15, further comprising a liquid carbon dioxide supply step of supplying the aforementioned liquid carbon dioxide.

19. The spraying method according to claim 15, further comprising a liquid carbon dioxide supply step for supplying the liquid carbon dioxide and a stock solution supply step for supplying the stock solution.

20. The spraying method according to claim 15, wherein in the mixed liquid obtained in the mixing step, the stock solution is dissolved or dispersed in the liquid carbon dioxide.

21. The spraying method according to claim 15, wherein the stock solution is at least one selected from the group consisting of lemon oil, essential oil components, algal oil, and paint.

22. The spraying method according to claim 15, wherein in the pressure-resistant vessel, the mass ratio of the stock solution to the liquid carbon dioxide (stock solution / liquid carbon dioxide) is 0.01 to 0.

99.

23. The spraying method according to claim 15, wherein the droplet size of the atomized stock solution sprayed in the spraying step is 0.1 nm or more and 0.5 μm.

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