Coating apparatus

Abstract

A coating apparatus is provided that includes: a supply device configured to supply a supercritical fluid; a mixing device configured to produce a mixture of the supercritical fluid and a functional additive; and a spraying device having a plurality of nozzle holes configured to spray the mixture supplied from the mixing device onto a substrate.

Description

FN202501228[DESCRIPTION][Title of Invention]COATING APPARATUS[Technical Field]

[0001] The present disclosure relates to a coating apparatus.[Background Art]

[0002] Conventional water-based dyeing of fabrics generally uses chemical agents such as solvents and surfactants. However, this method generates a large amount of waste liquid and consumes a large amount of energy in the drying process after dye application, resulting in a very high environmental burden. To address these issues, dyes that use supercritical carbon dioxide, which can be easily removed from the substrate by heating after application, have been studied.

[0003] For example, Patent literature 1 discloses a technique in which supercritical carbon dioxide is supplied from a fluid storage container, while a solvent or a functional additive in which a solid material is dissolved in a solvent is supplied from a reaction liquid container. These are pressurized and transported by a pump to be mixed together. Then, the resulting mixed fluid is discharged from a single nozzle and applied onto filamentous fibers.[Citation Fist][Patent Literature][PTL 1]Japanese Patent No. 5129756[Summary of Invention][Technical Problem]

[0004] However, since the apparatus disclosed in Patent literature 1 is configured to apply a dye onto fine fibers, it cannot efficiently apply a functional additive onto substrates having a large width.

[0005] An object of the present disclosure is to efficiently apply a functional additive onto a substrate.[Solution to Problem]

[0006] In order to solve the above problems, the present disclosure provides a coating apparatus including: a supply device configured to supply a supercritical fluid; a mixing device configured to produce a mixture of the supercritical fluid and a functional additive; and aFN202501228spraying device having a plurality of nozzle holes configured to spray the mixture supplied from the mixing device onto a substrate.[Advantageous Effects of Invention]

[0007] According to embodiments of the present invention, the functional additive can be efficiently applied onto the substrate.[Brief Description of Drawings]

[0008] A more complete appreciation of embodiments of the present disclosure and many of the attendant advantages and features thereof can be readily obtained and understood from the following detailed description with reference to the accompanying drawings.FIG. 1 is a schematic configuration diagram illustrating a coating apparatus according to one embodiment of the present invention.FIG. 2 is a schematic configuration diagram of a supply device and a mixing device.FIG. 3 is a perspective view of a spraying device.FIG. 4 is a schematic diagram of a flow channel member as seen from a substrate side.FIGs. 5A and 5B are cross-sectional views of a flow channel member perpendicular to a width direction and a substrate conveying direction, respectively.FIG. 6 is a perspective view of a modification of a flow channel member.FIG. 7 is a cross-sectional view of a flow channel member in which plate materials are stacked.FIG. 8 is diagram illustrating a modification of nozzle holes formed in a flow channel member.FIG. 9 is a diagram illustrating a modification of the arrangement of nozzle holes formed in a flow channel member.FIG. 10 is a diagram illustrating a spraying device including a plurality of flow channel members.FIG. 11 is a schematic configuration diagram illustrating a modification of a heating device of a coating apparatus.FIG. 12 is a schematic configuration diagram illustrating another modification of a heating device of a coating apparatus.FIG. 13 is a schematic configuration diagram illustrating yet another modification of a heating device of a coating apparatus.The accompanying drawings are intended to depict embodiments of the present disclosure and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. Also, identical or similar reference numerals designate identical or similar components throughout the several views.[Description of Embodiments]

[0009] FN202501228In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that have a similar function, operate in a similar manner, and achieve a similar result.Referring now to the drawings, embodiments of the present disclosure are described below. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.Hereinafter, embodiments according to the present invention are described with reference to the drawings. Note that in each drawing, the same or corresponding parts are designated by the same reference signs, and redundant description is appropriately simplified or omitted.

[0010] FIG. 1 is a schematic configuration diagram illustrating a coating apparatus according to one embodiment of the present invention.

[0011] As illustrated in FIG. 1, a coating apparatus 1 includes a supply device 10, mixing devices 20A to 20C, spraying devices 30A to 30C, heating devices 40A to 40C, an unwinder 61 serving as a feed-out member, and a rewinder 62 serving as a take-up member. The supply device 10 supplies supercritical carbon dioxide, which is a supercritical fluid, to the mixing devices 20A to 20C. Each of the mixing devices 20A to 20C produces a mixture (hereinafter simply referred to as “mixture”) by mixing the supercritical carbon dioxide with corresponding functional additives 21 A to 21C. The spraying devices 30A to 30C spray the mixture onto a substrate 50. The unwinder 61 holds the substrate 50 in a rolled form and feeds out the substrate 50 in the direction of arrow A, which indicates the conveying direction of the substrate, by rotating itself. The rewinder 62 takes up the substrate 50 that has been fed out in the direction of arrow A by rotating itself. Except for the differences in the types of functional additives 21 A to 21C being mixed, the mixing devices 20A to 20C, the spraying devices 30A to 30C, and the heating devices 40A to 40C have the same configuration and are hereinafter collectively referred to simply as the mixing device 20, the spraying device 30, and the heating device 40, respectively. Further, the functional additives 21 A to 21C are also collectively referred to as the functional additive 21.

[0012] The substrate 50 is conveyed in the direction of arrow A while being supported by a plurality of conveyance rollers 63 between the unwinder 61 and the rewinder 62. The unwinder 61 serving as the feed-out member, the rewinder 62 serving as the take-up member, and the conveyance rollers 63 constitute a conveyance unit of the present embodiment for conveying the substrate 50.

[0013] FN202501228The substrate 50 may be made of any suitable material selected according to the application. The substrate 50 of the present embodiment is a fabric, and a polymer material such as, for example, polyester, polypropylene, nylon, acrylic, polyurethane, vinylon, or aramid can be used. Further, it is preferable to use a polymer film or a polymer fiber as the substrate 50.

[0014] The supercritical carbon dioxide supplied from the supply device 10 is mixed with the functional additive 21 in the mixing device 20. The resulting mixture including the functional additive is then sprayed onto the substrate 50 by the spraying device 30. The heating device 40 heats the substrate 50 at positions downstream of spraying positions El to E3 of the respective spraying devices 30A to 30C in the substrate conveying direction. In this manner, the functional additive 21 is absorbed into the substrate 50.

[0015] By arranging the plurality of mixing devices 20A to 20C along the conveyance path of the substrate 50, a plurality of types of functional additives 21 A to 21C can be applied to and fixed on the substrate 50. Accordingly, the substrate 50 can be provided with multiple functions, such as by forming coatings of multiple colors on the substrate 50.

[0016] When a solvent or a solution obtained by dissolving a solid material in a solvent is used as the functional additive 21, an increase in environmental burden due to the large amount of solvent used becomes a problem. However, in the present embodiment, the environmental burden can be reduced by using a solid powder as the functional additive. However, in a case where the functional additive is poorly soluble in the supercritical carbon dioxide, a solvent such as ethanol may be used as a solubilizing aid.

[0017] Next, configurations of the supply device 10 and the mixing device 20 are described with reference to FIG. 2. FIG. 2 is a schematic configuration diagram of the supply device and the mixing device.

[0018] As illustrated in FIG. 2, the supply device 10 includes a cylinder 11, a high-pressure valve 101, a cooler 12, a high-pressure pump 13, a heater 14, and a back-pressure valve 102. The cylinder 11 stores carbon dioxide. The cooler 12 cools the liquid carbon dioxide supplied from the cylinder 11 to a saturation temperature or lower. The high-pressure pump 13 pressurizes the cooled liquid carbon dioxide to a predetermined pressure (e.g., a critical pressure of 7.3 MPa). The heater 14 heats the liquid carbon dioxide supplied from the high-pressure pump 13 to a predetermined temperature (e.g., a critical temperature of 31 °C) to bring it into a supercritical state. The back-pressure valve 102 returns an excess portion of the liquid carbon dioxide supplied from the high-pressure pump 13 to the downstream side of the high-pressure pump 13. As the high-pressure pump 13, a volumetric plunger pump isFN202501228preferably used, and a double plunger pump capable of controlling the discharge amount and preventing pulsation can be employed.

[0019] In particular, the supply device 10 of the present embodiment includes the cooler 12. The cooler 12 functions to lower the temperature of the liquid carbon dioxide by cooling during delivery, thereby maintaining it in a liquefied state. This enables quantitative delivery of the liquid carbon dioxide by the high-pressure pump 13. Further, the heater 14 is provided in the supply device 10 downstream of the cooler 12 in the liquid delivery direction. Specifically, the liquid carbon dioxide cooled by the cooler 12 is heated by the heater 14 to be brought into a supercritical state, thereby improving its solubility with the functional additive 21 that is mixed in the mixing device 20. Thus, by providing both the cooler 12 and the heater 14 in the supply device 10, it is possible to achieve both good liquid delivery performance in the supply device 10 and good solubility between the supercritical fluid and the functional additive 21 in the mixing device 20.

[0020] Examples of the cooler 12 include a chiller device that cools an object to be cooled by circulating cooling water. Further, examples of the high-pressure pump 13 include a double plunger pump capable of controlling the liquid discharge amount and preventing pulsation. However, the cooler 12 and the high-pressure pump 13 are not limited to these examples. Further, as the heater 14 heating the fluid, a heat exchanger (evaporator) is used. However, the configuration of the heater 14 is not limited to this example.

[0021] The mixing device 20 includes a high-pressure container 22, a stirring mechanism 23, a motor 24, a heater 25, and a waste liquid container 26. A high-pressure valve 103 is provided in the piping connecting the supply device 10 and the mixing device 20. A high-pressure valve 104 is provided in the piping connecting the mixing device 20 and the spraying device 30 (see FIG. 1). A high-pressure valve 105 is provided in the piping connecting the high-pressure container 22 and the waste liquid container 26.The supercritical carbon dioxide is sent into the high-pressure container 22 via the high-pressure valve 103. Inside the high-pressure container 22, the supercritical carbon dioxide and the functional additive 21 are stirred and mixed by the stirring mechanism 23. The resulting mixture is sent in the direction of arrow B through the high-pressure valve 104 and a piping 27, and is supplied to the spraying device 30.The stirring mechanism 23 is driven by the motor 24.

[0022] In the present embodiment, by providing the high-pressure container 22 in the mixing device 20, the functional additive 21 can be introduced into the high-pressure container 22 by means of pressure. Accordingly, as compared to a method in which the functional additive 21 is delivered using, for example, a liquid-feeding pump, even a solid powder-type functionalFN202501228additive 21 as in the present embodiment can be efficiently conveyed to the stirring position. As an example of the high-pressure container 22, a cylindrical container made of stainless steel having an outer diameter of 150 mm and an inner diameter of 65 mm can be mentioned. However, the configuration of the high-pressure container 22 is not limited thereto.

[0023] Examples of the stirring mechanism 23 include, but are not limited to, a magnetic impeller (a rotor having blades that rotate by a driving force from the motor), a single-shaft screw, a twin-screw that intermeshes, a twin-shaft mixer having a plurality of intermeshing or overlapping stirring elements, a kneader having spiral stirring elements that intermesh with each other, and a static mixer.

[0024] The solubility of the functional additive 21 in carbon dioxide depends on pressure and temperature, and tends to increase as the pressure or temperature increases. Thus, by detecting and appropriately controlling the pressure and temperature inside the high-pressure container 22 using a pressure gauge and a thermometer, the amount of the functional additive 21 sprayed from the spraying device 30 can be adjusted.

[0025] Further, it is preferable that each piping through which carbon dioxide, or the mixture of carbon dioxide and the functional additive 21, passes includes a mechanism maintaining the interior of the piping at a predetermined temperature. It is preferable to provide a heating mechanism or a heat-insulating member around the piping. The high-pressure container 22 and the piping 27 may be maintained at different temperatures.

[0026] After the coating operation is completed, the excess functional additive 21 remaining in the high-pressure container 22 can be discharged together with the supercritical carbon dioxide into the waste liquid container 26 by opening the high-pressure valve 105.

[0027] The heating device 40 includes a heating means, which can promote the diffusion of the functional material 21 into the substrate 50 by increasing the temperatures of the substrate 50 and the functional material 21 applied on the substrate 50. Examples of the heating means include, but are not limited to, conductive heating, convective heating, and radiant heating. However, from the viewpoints of reducing heating time and improving thermal efficiency, an infrared-type heating device can be preferably used. Further, the wavelength of the infrared rays can be appropriately selected depending on the object to be heated. By providing a radiation thermometer inside the heating device 40 to measure the surface temperature of the substrate 50, the substrate 50 can be heated to a desired temperature. Further, by providing, together with the radiation thermometer, a thermometer detecting the ambient temperature inside the heating device 40, overheating of the heating device 40 and the substrate 50 can be prevented, thereby ensuring the safety of the coating apparatus.FN202501228

[0028] Next, the detailed configuration of the spraying device is described with reference to FIG. 3 to FIG. 5B. FIG. 3 is a perspective view of the spraying device, FIG. 4 is a schematic view of the flow channel member as seen from the substrate side in a direction perpendicular to the coating surface of the substrate, FIG. 5A is a cross-sectional view taken along a direction perpendicular to the width direction, and FIG. 5B is a cross-sectional view taken along a direction perpendicular to the conveying direction of the substrate.

[0029] As illustrated in FIG. 3, the spraying device 30 includes a flow channel member 31. The flow channel member 31 extends in the direction of arrow C, which corresponds to the width direction of the substrate 50. The width direction of the substrate 50 refers to the direction, along the surface of the substrate 50, perpendicular to the conveying direction of the substrate 50.

[0030] One end of the flow channel member 31 is connected to the piping 27 via a joint 33. The mixture is supplied from the mixing device 20 (see FIG. 2) to the flow channel member 31 through the piping 27.

[0031] As illustrated in FIG. 4, a plurality of nozzle holes 32 are provided in the flow channel member 31. The plurality of the nozzle holes 32 are arranged side by side along the width direction of the substrate. A region indicated by the double -headed arrow D in FIG. 4 represents a passage region in the width direction of the substrate. In the present embodiment, the nozzle holes 32 are provided outside the passage region of the substrate in the width direction. In the present embodiment, the nozzle holes 32 are formed as circular through-holes having a circular cross section.

[0032] As illustrated in FIG. 5A, the flow channel member 31 is a tubular member having a circular cross section. As illustrated in FIG. 5B, the nozzle holes 32 are formed on the substrate side of the flow channel member 31. In the present embodiment, the nozzle holes 32 are formed at equal intervals in the width direction of the substrate. However, the arrangement is not limited thereto. The mixture flows through the flow channel, which is a hollow portion inside the flow channel member 31, and the mixture including the functional additive is sprayed onto the substrate through each of the nozzle holes 32.

[0033] The nozzle holes 32 can be formed by any known method such as mechanical processing, electrical discharge processing, or laser processing, and the appropriate method can be selected as needed in consideration of the shape of the nozzle holes, and the thickness and material of the flow channel member.

[0034] FN202501228By opening the high-pressure valve 104 illustrated in FIG. 2, the mixture of the supercritical carbon dioxide and the functional additive 21 is supplied from the flow channel inside the piping 27 to the flow channel member 31, and is sprayed from the nozzle holes 32. In the present embodiment, since the multiple nozzle holes 32 are provided in the width direction of the substrate, the functional additive can be sprayed over the entire width direction of the substrate. Accordingly, the functional additive 21 can be applied efficiently to the substrate, thereby improving the productivity of the coating apparatus. In the present embodiment, the dye as the functional additive 21 is uniformly applied to a fabric as the substrate 50, thereby dyeing the entire surface of the fabric.

[0035] In particular, by feeding the mixture including the supercritical fluid under high pressure through the piping 27 and into the flow channel member 31, the mixture can be made to flow with almost no pressure difference between the upstream side and downstream side.Accordingly, even when using the long flow channel member 31 and a simple configuration in which the nozzle holes 32 are formed without any special spraying mechanism on the spray side, the mixture can be uniformly sprayed from each of the nozzle holes 32. As a result, the functional additive can be applied uniformly in the width direction of the substrate 50.

[0036] Further, when a water-based dye is used as the functional additive, a large amount of waste liquid is generated, and a large amount of energy is required for drying. In contrast, by applying to the substrate the mixture of the functional additive 21 and the supercritical fluid as in the present embodiment, the functional additive can be applied to the substrate with a small environmental burden.

[0037] As illustrated in FIG. 1, in the present embodiment, three spraying devices 30A to 30C are disposed from the upstream side in the conveying direction of the substrate 50. The spraying devices 30A to 30C spray the mixture of mutually different functional additives 21 A to 21C and the supercritical carbon dioxide. In the present embodiment, dyes are used as the functional additive 21, and different colored dyes are used for the functional additives 21 A to 21C. By appropriately adjusting the pressure and temperature of each high-pressure container 22, thereby adjusting the application amount of each dye, the substrate 50 can be colored to a desired color tone.

[0038] Specifically, as the functional additives 21 A to 21C in the present embodiment, disperse dyes are used. Examples thereof include C.I. Disperse Red (e.g., C.I. Disperse Red 1, C.I. Disperse Red 13, C.I. Disperse Red 54, C.I. Disperse Red 60, etc.), C.I. Disperse Blue (e.g., C.I.Disperse Blue 1, C.I. Disperse Blue 3, C.I. Disperse Blue 7, C.I. Disperse Blue 14, C.I.Disperse Blue 301, C.I. Disperse Blue 354, etc.), and C.I. Disperse Yellow (e.g., C.I. Disperse Yellow 3, C.I. Disperse Yellow 5, C.I. Disperse Yellow 7, C.I. Disperse Yellow 42, etc.). ItFN202501228should be noted that the number of spraying devices, the number of heating devices, as well as the types and number of functional materials, are not limited to these examples.

[0039] In the present embodiment, as illustrated in FIG. 4, the nozzle holes 32 are also provided outside the passage region D in the substrate width direction. This configuration allows the coating concentration of the functional additive on the substrate to be uniform across the width direction.That is, the functional additive sprayed from each nozzle hole 32 spreads as it is sprayed onto the substrate, and the coating ranges of the functional additive sprayed from the multiple nozzle holes 32 overlap on the substrate. Consequently, at the ends in the width direction, the number of nozzle holes 32 whose coating ranges overlap is smaller at the ends than at the center, resulting in a lower coating concentration at the ends than at the center. Thus, by providing the nozzle holes 32 outside the passage region D in the width direction of the substrate, as in the present embodiment, the ends where the coating concentration is lower can be positioned outside the passage region of the substrate, thereby enabling the coating concentration of the functional additive to be made uniform across the substrate.

[0040] The tubular flow channel member 31 may have, for example, a circular cross section as illustrated in FIG. 3, or a rectangular cross section as illustrated in FIG. 6. For example, even if the substrate 50 has a large width, such a flow channel member 31 can be formed at low cost by using a standard piping specified in standards such as ISO 1127 and ASTM A2699.

[0041] Further, the flow channel member 31 illustrated in FIG. 6 can also be formed, as illustrated in FIG. 7, by stacking multiple plate materials 35. The plate materials 35 may be joined together, for example, by diffusion bonding. In this case, the shape of the flow channel in the flow channel member 31 can be freely changed by partially changing the length of the plate materials, or the like. Thus, the flow channel inside the flow channel member 31 can be formed with a high degree of freedom.

[0042] The flow channel member 31 is designed taking into consideration its pressure resistance, corrosion resistance, and the coating amount applied to the substrate. Specifically, these functions are satisfied by appropriately setting parameters such as the material and thickness of the flow channel member 31, the nozzle dimensions, the pitch between nozzles, and the distance between the nozzle holes and the substrate. As the material for the flow channel member 31, it is preferable to use stainless steel (SUS304, SUS316, etc.) or a nickel-based alloy such as Inconel (registered trademark, particularly Inconel 600, Inconel 625, Inconel 718, Inconel X750, etc.) or Hastelloy (registered trademark, particularly Hastelloy B2, Hastelloy B3, Hastelloy C276, or Hastelloy C22).

[0043] FN202501228Further, as illustrated in FIG. 8, the nozzle holes 32 can be formed as wide holes extending in the width direction. This configuration allows the supercritical carbon dioxide to expand more easily in the substrate width direction when the mixture including the functional additive is sprayed from the nozzle holes 32, enabling the functional additive to be sprayed over a wider range in the width direction. Consequently, the functional additive can be applied more efficiently over a wider range. The phrase “nozzle holes 32 being wide in the width direction” means that, when the nozzle holes 32 are viewed from the substrate side in a direction perpendicular to the coating surface of the substrate, the length of each nozzle hole in the width direction is longer than its length in the direction perpendicular to the width direction. Alternatively, in terms of the length of the nozzle holes 32 along the surface of the flow channel member 31, the length of each nozzle hole 32 in the width direction may be longer than its length in the direction intersecting the width direction.

[0044] Further, the nozzle holes 32 may be formed in multiple rows. For example, as illustrated in FIG. 9, the nozzle holes 32 can be formed in two rows, a nozzle row 320A and a nozzle row 320B, each having the nozzle holes 32 aligned in the width direction. In FIG. 9, the nozzle holes 32 in the nozzle row 320A and the nozzle row 320B are offset from each other in the width direction, so that the nozzle holes 32 are arranged alternately in the width direction. In other words, when viewed in a direction perpendicular to the coating surface of the substrate, as viewed in FIG. 9, the nozzle holes 32 are arranged in a staggered pattern. This allows the amount of functional additive applied to the substrate to be more uniform in the width direction, thereby improving the functionality of the functional additive. Further, by providing the multiple rows of the nozzle holes 32, the spray amount of the functional additive can be increased, thereby improving the coating speed of the coating apparatus. However, three or more nozzle rows may be provided, and the arrangement of the nozzle holes can be selected appropriately.

[0045] Further, the spraying device may be configured to include multiple flow channel members. For example, as illustrated in FIG. 10, a flow channel member 31A and a flow channel member 3 IB can be arranged side by side in the substrate conveying direction. In the present embodiment, the nozzle rows 320A and 320B are formed respectively on the flow channel members 31A and 3 IB. However, multiple nozzle rows may also be provided. Then, the nozzle holes 32 of the nozzle rows 320A and 320B are arranged in a staggered pattern. In the present embodiment as well, the amount of functional additive applied to the substrate can be made more uniform in the width direction. Also, in the present embodiment, it is possible to increase the spraying amount of the functional additive, thereby improving the coating speed of the coating apparatus. For example, the mixture is supplied to the flow channel member 31 A and the flow channel member 3 IB via a branched piping from the common mixing device. However, the mixture may be supplied to them from different mixing devices.FN202501228

[0046] Next, a modification of the heating device provided in the coating apparatus is described with reference to FIG. 11 to FIG. 13.

[0047] As illustrated in FIG. 11, the coating apparatus 1 includes a single heating device 40 located downstream of the spraying devices 30A to 30C in a substrate conveying direction A. That is, after the mixture is sprayed onto the substrate 50 by the spraying devices 30A to 30C, heating is performed by the heating device 40. Compared to the configuration illustrated in FIG. 1, this allows the coating apparatus 1 to be made more compact and cost-effective.

[0048] The coating apparatus 1 illustrated in FIG. 12 includes, in addition to the heating devices 40A to 40C of FIG. 1, an upstream heating device 41 located upstream of the spraying devices 30A to 30C in the substrate conveying direction A. The upstream heating device 41 is, for example, an infrared-type heating device. In the present embodiment, the substrate 50 can be preheated upstream of the spraying positions El to E3 of the spraying devices 30, thereby improving the absorption of the functional additive 21 into the substrate 50.

[0049] Further, the coating apparatus 1 illustrated in FIG. 13 includes a downstream heating device 42, in addition to the heating devices 40A to 40C provided downstream of the respective spraying devices 30A to 30C. The downstream heating device 42 includes a plurality of heating rollers 43. The heating rollers 43 contact the substrate 50 to heat the substrate 50. As a result, the absorption of the functional additive 21 into the substrate 50 can be further improved.

[0050] The above configurations of the heating devices illustrated in FIG. 1 and FIG. 11 to FIG. 13 may be combined.

[0051] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0052] The supercritical fluid refers to a fluid under supercritical conditions at the critical temperature or higher and at the critical pressure or higher. For example, the supercritical carbon dioxide fluid refers to carbon dioxide fluid under supercritical conditions at a temperature of 31.1 °C or higher, which is the critical temperature of carbon dioxide, and a pressure of 7.48 MPa or higher, which is the critical pressure of carbon dioxide.

[0053] Further, the supercritical fluid can be used together with an entrainer (solubilizing aid).Examples of the entrainer include, but are not limited to: an alcohol such as methanol,FN202501228ethanol, or propanol; a ketone such as acetone or methyl ethyl ketone; and an organic solvent such as toluene, ethyl acetate, or tetrahydrofuran. These may be used alone or in combination of two or more types.

[0054] The functional additive is not particularly limited and can be appropriately selected depending on the purpose and the physicochemical properties of the substrate. Examples thereof include, but are not limited to, a dye, a preservative, an antifungal agent, a waterproofing agent, a conductive agent, a UV absorber, a strength enhancer, an oxidizing agent, a neutralizing agent, a metal or a catalyst deactivator, a slip agent, a light stabilizer, an anti-blocking agent, a lubricant, a fire retardant, a coupling agent, a processing aid, an antistatic agent, a nucleating agent, and a foaming agent. Of these, a dye is preferable for dyeing applications, and a preservative, an antifungal agent, a waterproofing agent, and a conductive agent are preferable for other various applications. These agents may be used alone or in combination of two or more types. Specifically, two or more agents may be mixed and applied in a single application step, or two or more agents may be applied individually in two or more application steps.

[0055] As the functional additive, it is preferable to select a substance that does not elute from the substrate under actual use conditions and that is substantially insoluble in the substrate under normal conditions, or, if soluble, dissolves only in an extremely small amount.

[0056] Examples of the dye include, but are not limited to, a disperse dye, an acid dye, an acid mordant dye, a basic dye, a direct dye, a vat dye, a reactive dye, and a naphthol dye. Of these, a disperse dye in the above embodiment is preferable because it exhibits excellent solubility in the supercritical carbon dioxide fluid. Note that when performing water-based dyeing using the disperse dye, a dispersant can be included to stably disperse the disperse dye in water.

[0057] Examples of the above disperse dye include, but are not limited to, Disperse Yellow 54, Disperse Yellow 122, Disperse Yellow 124, Disperse Yellow 128, Disperse Yellow 134, Disperse Yellow 140, Disperse Orange 5, Disperse Orange 25, Disperse Orange 37, Disperse Orange 93, Disperse Orange 103, Disperse Orange 112, Disperse Orange 134, Disperse Orange 370, Disperse Green 7, Disperse Violet 61, Disperse Violet 63, Disperse Brown 1, Disperse Brown 13, Disperse Blue 14, Disperse Blue 27, Disperse Blue 54, Disperse Blue 56, Disperse Blue 176, Disperse Blue 182, Disperse Blue 193, Disperse Red 60, Disperse Red 146, Disperse Red 199, Disperse Red 202, Disperse Red 204, and Disperse Red 291. These may be used alone or in combination of two or more types.

[0058] Examples of the preservative and the antifungal agent include, but are not limited to, MARUKACIDE YP-DP (manufactured by Osaka Kasei Co.), AMORDEN HS (manufactured by Daiwa Chemical Industries Co., Ltd.), catechin, chitosan, flavone, acrylonitrile, and aFN202501228polyanion having multiple anionic functional groups, such as a carboxyl group, a sulfonic acid group, a sulfate group, and a phosphate group, per molecule.

[0059] Examples of the waterproofing agent include, but are not limited to, NEOSEED (manufactured by Nicca Chemical Co., Ltd.), QUEEENSET PSO-5500 (manufactured Kotani Chemical Industry Co., Ltd.), and POLONCOAT-E (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0060] Examples of the conductive agent include, but are not limited to, silver acetylacetonate, dimethyl(cyclooctadiene)platinum(II), and bis(acetylacetonato)palladium.

[0061] Examples of the UV absorber include, but are not limited to, a benzotriazole-based agent and a benzophenone-based agent.

[0062] Examples of the strength enhancer include, but are not limited to, silicone oil.

[0063] Examples of the neutralizing agent and the catalyst deactivator include, but are not limited to, zinc oxide, zinc stearate, an aliphatic amine, and an aliphatic amide.

[0064] Examples of the metal include, but are not limited to, copper, silver, nickel, and gold.

[0065] Examples of the slip agent include, but are not limited to, erucamide, oleamide, and ethylene bis-stearamide.

[0066] Examples of the light stabilizer include, but are not limited to, a benzophenone -based agent.

[0067] Examples of the anti-blocking agent include, but are not limited to, diatomaceous silica, clay, and talc.

[0068] Examples of the lubricant include, but are not limited to, an organically modified polydimethylsiloxane. Examples of the processing aid include, but are not limited to, calcium stearate and an organically modified polydimethylsiloxane.

[0069] Examples of the antistatic agent include, but are not limited to, glycerol monostearate, an ethoxylated amine, a polyethylene glycol ester, and a quaternary ammonium compound.

[0070] Examples of the foaming agent include, but are not limited to, azodicarbonamide and sodium bicarbonate.

[0071] FN202501228Aspects of the present invention are, for example, as follows.< Aspect 1 >A coating apparatus including:a supply device configured to supply a supercritical fluid;a mixing device configured to produce a mixture of the supercritical fluid and a functional additive; anda spraying device having a plurality of nozzle holes configured to spray the mixture supplied from the mixing device onto a substrate.< Aspect 2>The coating apparatus according to the < Aspect 1>, in which the supply device includes a cooler configured to cool a liquid and a heater configured to heat the liquid to convert the liquid into the supercritical fluid.< Aspect 3>The coating apparatus according to the <Aspect 1> or <Aspect 2>, in which the mixing device includes a high-pressure container in which the functional additive is put and mixed with the supercritical fluid.< Aspect 4>The coating apparatus according to any of the < Aspect 1> to < Aspect 3>, in which the functional additive is a solid powder.< Aspect 5>The coating apparatus according to any of the <Aspect 1> to <Aspect 4>, further including: a conveyance unit configured to convey the substrate; anda heating device configured to heat the substrate at a position downstream of a spraying position where the mixture is sprayed onto the substrate in a conveying direction of the substrate.< Aspect 6>The coating apparatus according to the < Aspect 5>,in which the spraying device includes a plurality of spraying devices, andthe heating device includes a plurality of heating devices respectively corresponding to the plurality of spraying devices.< Aspect 7 >The coating apparatus according to the <Aspect 5> or <Aspect 6>, further including an upstream heating device configured to heat the substrate, the upstream heating device disposed upstream of the spraying position where the mixture is sprayed onto the substrate in the conveying direction of the substrate.< Aspect 8>The coating apparatus according to any of the < Aspect 5> to < Aspect 7>, further including a downstream heating device configured to heat the substrate, the downstream heating deviceFN202501228disposed downstream of the heating device and the spraying device in the conveying direction of the substrate.< Aspect 9>The coating apparatus according to any of the < Aspect 1> to < Aspect 8>, in which the spraying device includes a flow channel member through which the mixture flows, the flow channel member extending in a width direction of the substrate and having the plurality of nozzle holes arranged side by side in the width direction.<Aspect 10>The coating apparatus according to the < Aspect 9>, in which the nozzle holes are arranged in a staggered pattern.< Aspect 11 >The coating apparatus according to the <Aspect 9> or <Aspect 10>, in which the flow path member is tubular with a circular or rectangular cross section.<Aspect 12>The coating apparatus according to any of the <Aspect 9> to <Aspect 11>, in which the flow channel member has the rectangular cross section and is formed of a plurality of plate materials stacked in a direction perpendicular to the width direction.< Aspect 13 >The coating apparatus according to any of the <Aspect 9> to <Aspect 12>, in which the flow channel member comprises stainless steel or a nickel alloy.<Aspect 14>The coating apparatus according to any of the <Aspect 9> to <Aspect 12>, in which the flow channel member comprises Inconel or Hastelloy.< Aspect 15 >The coating apparatus according to any of the <Aspect 1> to <Aspect 14>, in which each of the nozzle holes is circular.< Aspect 16>The coating apparatus according to any of the < Aspect 1> to < Aspect 15>, in which each of the nozzle holes is elongated in the width direction of the substrate.< Aspect 17 >The coating apparatus according to any of the <Aspect 1> to <Aspect 16>,in which the mixing device includes a plurality of mixing devices each including the different functional additive, andthe spraying device includes a plurality of spraying devices respectively corresponding to the plurality of mixing devices.< Aspect 18>The coating apparatus according to the < Aspect 17>,in which the functional additive is a dye, andFN202501228each of the plurality of mixing devices is configured to mix the dye with a different color and the supercritical fluid.<Aspect 19>The coating apparatus according to the < Aspect 17> or < Aspect 18>, in which the mixture sprayed from each of the plurality of spraying devices is different from each other in at least one of pressure and temperature.

[0072] The above-described embodiments are illustrative and do not limit the present invention. Thus, numerous additional modifications and variations are possible in light of the above teachings. For example, elements and / or features of different illustrative embodiments may be combined with each other and / or substituted for each other within the scope of the present invention.

[0073] This patent application is based on and claims priority to Japanese Patent Application Nos.2025-004178 and 2025-160396, filed on January 10, 2025 and September 26, 2025, respectively, in the Japan Patent Office, the entire disclosure of each of which is hereby incorporated by reference herein.[Reference Signs List]

[0074] 1 Coating apparatus10 Supply device12 Cooler14 Heater20 Mixing device22 High-pressure container30 Spraying device31 Flow channel member32 Nozzle hole40 Heating device41 Upstream heating device42 Downstream heating device50 Substrate61 Unwinder (feed-out member)62 Rewinder (take-up member)A Substrate conveying directionC Substrate width direction

Claims

FN202501228[CLAIMS]1. A coating apparatus comprising:a supply device configured to supply a supercritical fluid;a mixing device configured to produce a mixture of the supercritical fluid and a functional additive; anda spraying device having a plurality of nozzle holes configured to spray the mixture supplied from the mixing device onto a substrate.

2. The coating apparatus according to claim 1, wherein the supply device includes:a cooler configured to cool a liquid; anda heater configured to heat the liquid to convert the liquid into the supercritical fluid.

3. The coating apparatus according to claim 1 or 2, wherein the mixing device includes:a high-pressure container in which the functional additive is put and mixed with the supercritical fluid.

4. The coating apparatus according to any one of claims 1 to 3, wherein the functional additive is a solid powder.

5. The coating apparatus according to any one of claims 1 to 4, further comprising:a conveyance unit configured to convey the substrate; anda heating device configured to heat the substrate at a position downstream of a spraying position where the mixture is sprayed onto the substrate in a conveying direction of the substrate.

6. The coating apparatus according to any one of claims 1 to 5, wherein the spraying device includes:a flow channel member through which the mixture flows, the flow channel member extending in a width direction of the substrate and having the plurality of nozzle holes arranged side by side in the width direction.

7. The coating apparatus according to any one of claims 1 to 6, wherein each of the nozzle holes is circular.FN2025012288. The coating apparatus according to any one of claims 1 to 7, wherein each of the nozzle holes is elongated in a width direction of the substrate.

9. The coating apparatus according to claim 6, wherein the nozzle holes are arranged in a staggered pattern.

10. The coating apparatus according to claim 6 or 9, wherein the flow channel member is tubular with a circular or rectangular cross section.

11. The coating apparatus according to any one of claims 6, 9, and 10, wherein the flow channel member has the rectangular cross section and is formed of a plurality of plate materials stacked in a direction perpendicular to the width direction.

12. The coating apparatus according to any one of claims 1 to 11,wherein the mixing device includes a plurality of mixing devices each including a different functional additive, andthe spraying device includes a plurality of spraying devices respectively corresponding to the plurality of mixing devices.

13. The coating apparatus according to any one of claims 1 to 12,wherein the functional additive is a dye, andeach of the plurality of mixing devices is configured to mix the dye with a different color and the supercritical fluid.

14. The coating apparatus according to any one of claims 1 to 13, wherein the mixture sprayed from each of the plurality of spraying devices is different from each other in at least one of pressure and temperature.

15. The coating apparatus according to any one of claims 6, 9, 10, and 11, wherein the flow channel member comprises stainless steel or a nickel alloy.

16. The coating apparatus according to any one of claims 6, 9, 10, and 11, wherein the flow channel member comprises Inconel or Hastelloy.

17. The coating apparatus according to claim 5,wherein the spraying device includes a plurality of spraying devices, andthe heating device includes a plurality of heating devices respectively corresponding to the plurality of spraying devices.FN20250122818. The coating apparatus according to claim 5 or 17, further comprising: an upstream heating device configured to heat the substrate, the upstream heating device disposed upstream of the spraying position where the mixture is sprayed onto the substrate in the conveying direction of the substrate.

19. The coating apparatus according to any one of claims 5, 17, and 18, further comprising:a downstream heating device configured to heat the substrate, the downstream heating device disposed downstream of the heating device and the spraying device in the conveying direction of the substrate.

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