Washing-liquid discharge nozzle and method for washing object to be washed

Abstract

A nozzle (1) is a washing-liquid discharge nozzle. The nozzle (1) preferably has a discharge plate (2) provided with one or more through holes (21) from which liquid is discharged. Each through hole (21) preferably has a tapered shape in which the inner diameter thereof decreases in a discharge direction F of liquid L. The inner diameter of a discharge port (23) of each through hole (21) is preferably 10 to 200 μｍ, more preferably 20 to 150 μｍ, and even more preferably 20 to 110 μｍ.

Description

Cleaning liquid discharge nozzle and cleaning method for object to be cleaned

[0001] The present invention relates to a cleaning liquid ejection nozzle and a method for cleaning an object to be cleaned.

[0002] Conventionally, cleaning devices that clean the surface of an object to be cleaned by discharging a liquid onto the surface have been known. For example, Patent Document 1 proposes a cleaning device that includes a liquid spray nozzle having a spray nozzle hole, a pressurized liquid supply unit that pressurizes the liquid and sends it to the liquid spray nozzle, and a control unit that controls the operation of the pressurized liquid supply unit to cause the liquid sprayed from the spray nozzle hole to fly in a state in which the liquid is broken up into droplets from a continuous stream.

[0003] US2022 / 266266A1

[0004] The present invention relates to a cleaning liquid ejection nozzle. In one embodiment, the nozzle preferably includes an ejection plate having one or more through-holes through which a liquid is ejected. In one embodiment, the through-hole preferably has a tapered shape in which the inner diameter decreases in the ejection direction of the liquid. In one embodiment, the inner diameter of the ejection opening in the through-hole preferably ranges from 10 μm to 200 μm.

[0005] The present invention also relates to a cleaning method using a cleaning liquid discharge nozzle. In one embodiment, it is preferable to discharge a liquid from the discharge port of the through hole and apply the liquid to a portion to be cleaned of the object to be cleaned, thereby removing dirt from the surface of the object to be cleaned.

[0006] FIG. 1(a) is a perspective view showing a preferred embodiment of the liquid ejection nozzle of the present invention. FIG. 1(b) is a cross-sectional view taken along line II of FIG. 1(a). FIG. 2(a) is an enlarged cross-sectional view of the through-hole shown in FIG. 1. FIG. 2(b) is an enlarged cross-sectional view showing another embodiment of the through-hole. FIG. 3 is a plan view of the ejection plate of the nozzle shown in FIG. 1. FIG. 4(a) is a plan view showing the arrangement of the through-holes shown in FIG. 3. FIG. 4(b) is a plan view showing another embodiment of the arrangement of the through-holes. FIG. 5 is a view equivalent to FIG. 2 showing another embodiment of the through-hole according to the present invention. FIG. 6 is a side view schematically showing a state in which liquid is ejected in a continuous stream from the nozzle shown in FIG. 1. FIG. 7 is a perspective view illustrating how to use the nozzle shown in FIG. 1, showing how to cleanse the skin. FIG. 8 is an enlarged perspective view illustrating how to use the nozzle shown in FIG. 1, showing how to cleanse the surface of teeth. FIG. 9 is a side photograph showing how liquid is ejected from a conventional liquid ejection nozzle. Fig. 10 is a side photograph showing a state in which liquid is discharged from the liquid discharge nozzle of the present invention.Fig. 11 is a view corresponding to Fig. 2 showing still another embodiment of a through hole according to the present invention. Detailed Description of the Invention

[0007] A cleaning device that discharges a liquid onto the surface of an object to be cleaned to clean the surface is preferably capable of safely and efficiently cleaning dirt from the surface of the object to be cleaned. However, the discharged liquid in the cleaning device tends to spread or disperse (see FIG. 9 ), making it difficult to accurately apply the liquid to the desired area. As a result, the liquid may hit unintended areas, such as getting into the eyes. In addition, there are cases where it is difficult to efficiently clean the surface of the object to be cleaned. The cleaning device described in Patent Document 1 does not consider how to suppress the dispersion of the discharged liquid, leaving room for improvement.

[0008] Therefore, the present invention relates to a cleaning liquid discharge nozzle that can accurately apply liquid to dirt on the surface of an object to be cleaned, and can safely and efficiently clean the dirt from the surface of the object to be cleaned, and a method for using the same.

[0009] A cleaning liquid discharge nozzle 1 (hereinafter also referred to as "nozzle 1") of the present invention will be described below with reference to a preferred embodiment. The nozzle 1 of the present invention is typically used to clean a surface S to be cleaned, including keratinous materials, teeth, etc. The object to be cleaned is preferably a human, but may also be a non-human animal, such as a pet dog or cat. Keratinous materials include skin, scalp, hair, nails, etc. Skin includes skin on the face, arms, hands, feet, back, etc. Dirt on the surface S to be cleaned with the nozzle 1 typically includes sebum, sweat, dead skin cells, pollen, yellow sand, PM2.5, mud, sand, viruses, food, dental plaque, etc. The nozzle 1 has a flow path for liquid L therein.

[0010] The nozzle 1 of the present invention preferably includes a cylindrical base 4 in which a large-diameter cylinder 46 and a small-diameter cylinder 45 having an inner diameter smaller than that of the large-diameter cylinder 46 are connected together, and a discharge plate 2 fixed to the large-diameter cylinder 46 (see FIG. 1(a)). Typically, the base 4 has the small-diameter cylinder 45 connected to one axial end of the large-diameter cylinder 46, with the axial directions of the large-diameter cylinder 46 and the small-diameter cylinder 45 aligned (see FIG. 1(b)). Typically, the opening of the large-diameter cylinder 46 on the axial opposite side to the small-diameter cylinder 45 is closed by the discharge plate 2.

[0011] A liquid supply unit (not shown) that supplies the liquid L is typically connected to the end of the small-diameter cylinder 45 opposite the large-diameter cylinder 46 in the axial direction. The liquid supply unit typically includes a supply pump. The liquid supply unit is controlled by the supply pump to apply pressure for discharging the liquid L. This is preferably configured to supply a predetermined amount of liquid L to the nozzle 1 continuously or discontinuously, or to stop the supply. The small-diameter cylinder 45 of this embodiment has a flange 49 at the end opposite the large-diameter cylinder 46 in the axial direction. The flange 49 protrudes radially outward from the outer circumferential surface of the small-diameter cylinder 45, and is provided with a locking portion (not shown) for connecting a supply hose provided by the liquid supply unit.

[0012] The nozzle 1 typically has a discharge direction F along the axial direction of the base 4. This discharge direction F typically coincides with the axial direction of the large-diameter tube 46 and the small-diameter tube 45. Hereinafter, the end of the nozzle 1 facing the discharge plate 2 in the discharge direction F will be referred to as the "tip end" and the end opposite the discharge plate 2 in the discharge direction F will be referred to as the "base end." In the nozzle 1, the internal spaces of the large-diameter tube 46 and the small-diameter tube 45 preferably communicate with each other in the discharge direction F. This allows the internal spaces to form a flow path for the liquid L. The liquid L supplied to the nozzle 1, i.e., the liquid L supplied from the opening on the base end side of the small-diameter tube 45, moves through the small-diameter tube 45, the large-diameter tube 46, and the discharge plate 2 in this order. In the base 4 of the present invention, the length of the small-diameter tube 45 in the discharge direction may be longer than that of the large-diameter tube 46. That is, the base 4 may have a mushroom shape in a cross section along the discharge direction F (see FIG. 1( b)).

[0013] The discharge plate 2 is a sheet-like member and preferably has a front surface and a back surface. The back surface of the discharge plate 2 is typically the surface facing the large-diameter tube 46 of the base 4. The discharge plate 2 preferably covers the entire opening at the tip end of the large-diameter tube 46 and is liquid-tightly joined to the large-diameter tube 46 by a joint 5 formed along the periphery of the opening. Such a joint 5 can be formed by known joining methods such as heat fusion, ultrasonic waves, or adhesives. The discharge plate 2 may be a flat plate as shown in FIG. 1( b) or a curved plate that is entirely or partially curved. The front surface or back surface of the discharge plate 2 may be smooth or uneven. The discharge plate 2 preferably has one or more through holes 21 penetrating the discharge plate 2 in the thickness direction. The through hole 21 preferably has an inlet 22 through which the liquid L flows and an outlet 23 through which the liquid L is discharged in the discharge direction F. The inlet 22 and the outlet 23 are in communication with each other, and the central axes of the inlet 22 and the outlet 23 are aligned. The liquid L supplied to the nozzle 1 is discharged to the outside of the nozzle 1 through the through-hole 21. A typical example of this is shown in Figure 1(b).

[0014] The through hole 21 of the present invention typically has a circular shape in a cross section perpendicular to the discharge direction F. The cross-sectional shape of the through hole 21 is not particularly limited, and may be a square, an ellipse, or the like. From the viewpoint of improving the uniformity of the discharge pressure in the through hole 21, it is preferable that the cross-sectional shape of the through hole 21 is a circular shape.

[0015] The ejection plate 2 has a first direction X and a second direction Y perpendicular to the first direction X in a plan view (see FIG. 3 ). The ejection plate 2 typically has a plurality of through holes 21 arranged in a dispersed state in a plan view. That is, the plurality of through holes 21 are arranged in a dispersed state in the first direction X and the second direction Y. A typical ejection plate 2 has a through hole row 21L in which the plurality of through holes 21 are arranged at intervals along the second direction Y. Furthermore, two or more rows of the through hole rows 21L are provided at intervals in the first direction X. The positions of the through holes 21 constituting the through hole rows in the second direction Y of adjacent through hole rows 21L adjacent to each other in the first direction X are aligned with each other. Alternatively, the nozzle 1 may have only one through hole row 21L.

[0016] The discharge plate 2 typically has a through-hole arrangement region 21R in which two or more through-holes 21 are arranged. The through-hole arrangement region 21R typically has two or more rows of the aforementioned through-hole rows 21L arranged therein. The contour shape of the through-hole arrangement region 21R in a plan view can be any shape, such as a circle, an ellipse, a rectangle, a hexagon, or a substantially square shape with rounded corners. A typical example is shown in FIG. 3 . The contour shape of the through-hole arrangement region 21R is the contour shape of an area defined by a virtual line K connecting the outer edges of the through-holes 21 located most outward in either or both of the first direction X and the second direction Y in a plan view.

[0017] The through-holes 21 in the discharge plate 2 preferably have a tapered shape in which the inner diameter decreases in the discharge direction F of the liquid L. That is, the inner diameter of the through-holes 21 preferably gradually decreases from the inlet 22 toward the outlet 23. The cross-sectional shape of the through-holes 21 along the discharge direction F preferably has a pair of tapered edges 21a, 21b that extend to converge toward the central axis of the outlet 23. From the viewpoint of reducing pressure loss, the pair of tapered edges 21a, 21b of the present invention are preferably curved edges that curve toward the central axis of the outlet 23 (see FIGS. 2(a) and 2(b)). In the cross-sectional view of the through-holes 21 along the discharge direction F, the portion where the tapered edges 21a, 21b exist is also referred to as the "tapered portion 24." The entire area of ​​the through-holes 21 in the discharge direction F from the inlet 22 to the outlet 23 may have the tapered portion 24. A typical example of this is shown in FIG. 2(a). Furthermore, the through hole 21 may partially have a tapered portion 24 on the discharge port 23 side in the discharge direction F. A typical example of this is shown in FIG. 2( b). In the latter case, the through hole 21 typically has a non-tapered portion 25 with a constant inner diameter on the inlet 22 side in the discharge direction F. The non-tapered portion 25 is a portion where the edge of the through hole 21 is parallel to the axial direction (discharge direction F) in a cross-sectional view of the through hole along the discharge direction F. Note that, from the viewpoint of further suppressing diffusion of the liquid L, it is preferable that the tapered portion 24 be formed closer to the discharge port 23 side in the discharge direction F than the non-tapered portion 25.

[0018] When the shape of the through-hole 21 in plan view is circular, the circle is not limited to a perfect circle, and may be an ellipse. When the through-hole 21 is an ellipse, for example, the ratio of the minor axis to the major axis (minor axis / major axis) is preferably less than 1.0, more preferably 0.98 or less, and even more preferably 0.95 or less. The diameter of the ellipse is the equivalent circle diameter converted into the diameter of a perfect circle with the same cross-sectional area.

[0019] From the viewpoint of improving the ejection performance, the inner diameter D2 of the ejection port 23 of the through-hole 21 is preferably 10 μm or more, more preferably 20 μm or more. From the viewpoint of improving the detergency, the inner diameter D2 of the ejection port 23 of the through-hole 21 is preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 110 μm or less.

[0020] It is practically difficult to form small-diameter, straight through-holes, for example, straight through-holes with an inner diameter of 250 μm or less, by machining. For example, drilling with a drill makes it difficult to form uniform holes due to the strength of the small-diameter drill and deformation caused by heat and vibrations generated in small areas during drilling, and it is also not easy to obtain small-diameter drills. Furthermore, forming the through-holes by means other than machining, such as a laser processing machine, raises issues such as an increase in the size of the processing machine and high installation costs and / or processing costs for the processing machine.

[0021] The discharge plate 2 of the present invention preferably has one or more through holes 21, each having an inner diameter D2 of the discharge port 23 within the aforementioned range, and the through holes 21 preferably have a tapered shape in which the inner diameter decreases in the discharge direction F of the liquid L. The inventors discovered that when liquid L is discharged from a nozzle 1 having such a configuration, the liquid L flows straight from each through hole 21 as an independent continuous stream (see FIGS. 6 and 10 ). More specifically, they discovered that the liquid discharged from each through hole 21 is less likely to diffuse or disperse. In particular, when there are multiple through holes 21, the liquid discharged from each through hole 21 does not merge, and the individual discharged liquids do not disperse, so that they accurately hit the area to be cleaned in a substantially linear continuous stream. This prevents the liquid L from hitting unintended areas, such as the eyes. Furthermore, because the liquid L can be accurately applied to the desired area, such as the stain, the cleaning time can be shortened and the amount of liquid L used can be reduced. As a result, stains on the object to be cleaned can be efficiently cleaned. Furthermore, the nozzle 1 of the present invention discharges the liquid L from the through-hole 21 whose outlet 23 has an inner diameter within the aforementioned range, thereby softening the contact (contact) with the area to be cleaned. This reduces damage to the area to be cleaned, allowing the dirt on the object to be cleaned to be safely cleaned. In this way, the nozzle 1 of the present invention can safely and efficiently clean dirt on the surface of the object to be cleaned while minimizing damage to the area to be cleaned.

[0022] From the viewpoint of further improving the linearity of the ejected liquid L, the inner diameter D1 of the inlet 22 in the through hole 21 is preferably 20 μm or more, and more preferably 50 μm or more, provided that it is larger than the inner diameter D2 of the ejection port 23. From the viewpoint of further suppressing the diffusion and dispersion of the ejected liquid L and enabling a larger water flow per unit area of ​​the part to be cleaned by reducing the distance between adjacent ejection ports 23, the inner diameter D1 of the inlet 22 in the through hole 21 is preferably 500 μm or less, more preferably 400 μm or less, and even more preferably 350 μm or more, provided that it is larger than the inner diameter D2 of the ejection port 23.

[0023] From the viewpoint of further improving the linearity of the discharged liquid L, the ratio (D1 / D2) of the inner diameter D1 of the inlet 22 to the inner diameter D2 of the discharge outlet 23 is preferably greater than 1.0, more preferably greater than 1.1, and even more preferably greater than 1.5. From the viewpoint of further preventing the diffusion and dispersion of the discharged liquid L and enabling a greater water flow per unit area of ​​the area to be cleaned by reducing the distance between adjacent discharge outlets 23, the ratio (D1 / D2) of the inner diameter D1 of the inlet 22 to the inner diameter D2 of the discharge outlet 23 is preferably equal to or less than 40, more preferably equal to or less than 20, and even more preferably equal to or less than 10. Taking the above into consideration, the ratio (D1 / D2) of the inner diameter D1 of the inlet 22 to the inner diameter D2 of the discharge outlet 23 is preferably greater than 1.0 and equal to or less than 40, more preferably equal to or greater than 1.1 and equal to or less than 20, and even more preferably equal to or greater than 1.5 and equal to or less than 10.

[0024] In the nozzle 1 of this embodiment, it is preferable to change the dimensions of the through hole 21 as appropriate depending on the area to be cleaned on the object to be cleaned. For example, when the nozzle 1 is used to clean skin, from the viewpoints of preventing nozzle clogging and further improving cleansing performance, the inner diameter D2 of the outlet 23 is preferably 15 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, and even more preferably 40 μm or more. Furthermore, from the viewpoints of further improving cleansing performance and further suppressing splashing of the liquid L during cleaning, the inner diameter D2 of the outlet 23 is preferably 100 μm or less, more preferably 80 μm or less, even more preferably 70 μm or less, and even more preferably 60 μm or less.

[0025] When using nozzle 1 to cleanse skin, the inner diameter D1 of inlet 22 is preferably 20 μm or more, more preferably 100 μm or more, even more preferably 150 μm or more, and even more preferably 200 μm or more, from the viewpoint of further improving the linearity of the discharged liquid L. Furthermore, from the viewpoint of applying a larger water flow per unit area of ​​the part to be cleaned by shortening the distance between adjacent discharge ports 23, the inner diameter D1 of inlet 22 is preferably 500 μm or less, more preferably 400 μm or less, and even more preferably 350 μm or less.

[0026] When the nozzle 1 of the present invention is used to clean the oral cavity, the inner diameter D2 of the outlet 23 is preferably 50 μm or more, more preferably 60 μm or more, and even more preferably 70 μm or more, from the viewpoint of further improving plaque removal from interdental areas, tooth surfaces, etc. Furthermore, from the viewpoint of softer contact (contact) with the oral cavity, the inner diameter D2 of the outlet 23 is preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 130 μm or less.

[0027] When the nozzle 1 is used to clean the oral cavity, the inner diameter D1 of the inlet 22 is preferably 70 μm or more, more preferably 100 μm or more, even more preferably 150 μm or more, and even more preferably 200 μm or more, from the viewpoint of further improving the linearity of the discharged liquid L. Furthermore, from the viewpoint of applying a larger amount of water flow per unit area of ​​the part to be cleaned by shortening the distance between adjacent discharge ports 23, the inner diameter D1 of the inlet 22 is preferably 700 μm or less, more preferably 400 μm or less, and even more preferably 350 μm or less.

[0028] From the viewpoint of improving the linearity of the ejected liquid L, the length T of the ejection flow path formed by the through-hole 21 of the nozzle 1 is preferably 100 μm or more, and more preferably 200 μm or more. From the viewpoint of reducing the pressure loss of the ejected liquid L, the length T of the ejection flow path is preferably 3000 μm or less, more preferably 2000 μm or less, and even more preferably 1000 μm or less.

[0029] In the present invention, the through hole arrangement region 21R is typically formed in a part of the ejection plate 2. That is, the ejection plate 2 of the present invention typically has the through hole arrangement region 21R in which a plurality of through holes 21 are formed, and a non-through hole arrangement region in which no through holes 21 are formed. In the ejection plate 2 of the present invention, the non-through hole arrangement region typically surrounds the periphery of the through hole arrangement region 21R in a plan view. This makes it more difficult for the ejection pressure applied to the ejection plate 2 to be dispersed, thereby further improving the cleaning power.

[0030] In order to further suppress dispersion of the discharge pressure and enhance the cleaning power, the unit area (1 cm ) of the discharge plate 2 when the nozzle 1 is viewed from above is ２The number N of through holes 21 per unit area (hereinafter also referred to as "the number N of through holes 21 per unit area") is preferably 1500 / cm ２ or less, more preferably 1000 particles / cm ２ More preferably, 500 particles / cm or less ２ From the viewpoint of increasing the number of nozzles and further improving the cleaning efficiency, the number N of through holes 21 per unit area is preferably 20 / cm ２ More preferably, 50 particles / cm ２ More preferably, 100 particles / cm ２ The number N of the through holes 21 per unit area can be calculated by the following method.

[0031] <Method of calculating the number N of through holes 21 per unit area> The number N of through holes 21 is calculated by dividing the total area (cm ) of the through hole arrangement region 21R in which the through holes 21 are arranged in a dispersed manner in the planar direction when the nozzle 1 is viewed from above. ２ ) and the number of through holes 21 included in the region, the number of through holes / total area of ​​the through-hole arrangement region 21R can be calculated.

[0032] In the present invention, it is preferable that all of the through holes 21 present in the ejection plate 2 have a tapered shape having the above-mentioned configuration. At least some of the plurality of through holes 21 may have a tapered shape. From the viewpoint of further suppressing coalescence of the ejected liquid L, the proportion of the through holes 21 having a tapered shape to the total number of through holes 21 is preferably 50% or more and 100% or less, more preferably 80% or more and 100% or less.

[0033] To ensure that the water flow is directed precisely at the area to be cleaned, the area ratio of the through-hole region 21R in the discharge plate 2 is preferably 10% or more, and more preferably 50% or more. To further suppress dispersion of the discharge pressure and further enhance cleaning power, the area ratio is preferably 100% or less, and more preferably 80% or less.

[0034] From the viewpoint of further suppressing coalescence of the ejected liquid L, the distance G between the centers of adjacent through holes 21 is preferably 0.1 mm or more, more preferably 0.2 mm or more, when the nozzle 1 is viewed in a plan view. From the viewpoint of further improving cleaning power, the distance G is preferably 3 mm or less, more preferably 2 mm or less. When the through holes 21 are adjacent to each other in both the first direction X and the second direction Y, only one of the distance Gx between the centers of adjacent through holes 21 in the first direction X and the distance Gy between the centers of adjacent through holes 21 in the second direction Y may be within the above-mentioned range. Both the distance Gx and the distance Gy may be within the above-mentioned range (see FIG. 4( a)).

[0035] In the nozzle 1 of the present invention, the positions of the through holes 21 constituting adjacent through hole rows 21L in the first direction X do not have to match in the second direction Y. Typically, the phases of the arrangement of the through holes 21 in adjacent through hole rows 21L in the first direction X are shifted, and the through holes 21 are arranged in a staggered pattern overall. When the positions in the second direction Y of the through holes 21 constituting adjacent through hole rows 21L in the first direction X do not match, the distance Gx between the centers of the through holes 21 adjacent in the first direction X is defined as the distance along the first direction X between the through holes 21 constituting adjacent through hole rows 21L in the first direction X. An example is shown in FIG. 4( b ).

[0036] Next, the constituent materials of the nozzle 1 will be described. From the viewpoint of improving the handleability and processability of the material, the discharge plate 2 in the nozzle 1 preferably contains a thermoplastic resin. More preferably, the discharge plate 2 is formed from a base sheet containing a thermoplastic resin. The thermoplastic resin may contain one or more selected from polyolefin, polyester, polyamide, polyamideimide, polyetheretherketone, polyetherimide, polycarbonate, polyvinyl chloride, acrylic resin, polystyrene resin, etc. The polyolefin may contain one or more selected from polypropylene, polyethylene, etc. The polyester may contain one or more selected from polyethylene terephthalate, polybutylene terephthalate, polyfatty acid ester, polylactic acid, polycaprolactone, polybutylene succinate, etc. The polyamide may contain one or more selected from nylon, etc. From the viewpoint of biodegradability, it is preferable to contain a polyfatty acid ester. The polyfatty acid ester may contain one or more selected from polylactic acid and polyglycolic acid.

[0037] When the joint 5 is formed by fusion, from the viewpoint of ease of forming the joint, it is preferable that the base 4 of the nozzle 1 is formed containing the same type of thermoplastic resin as the discharge plate 2. Note that when the joint 5 is formed using an adhesive, the base 4 may be formed of a material different from that of the discharge plate 2, and may be made of, for example, metal.

[0038] From the viewpoint of further improving the moldability and dimensional stability of the through hole 21, the mass ratio of the thermoplastic resin contained in the nozzle 1 to the total mass of the nozzle 1 is preferably 50 mass% or more, more preferably 70 mass% or more. Furthermore, a functional agent may be optionally added to the nozzle 1 to impart various effects. In this case, the mass ratio of the thermoplastic resin contained in the nozzle 1 to the total mass of the nozzle 1 is preferably 100 mass% or less. Here, the various functional agents may be one or more selected from antibacterial agents, bactericides, moisturizing agents, flow improvers, antistatic agents, colorants, etc.

[0039] While the present invention has been described based on preferred embodiments, it is not limited to the above-described embodiments and can be modified as appropriate. There are no particular limitations on the arrangement pattern of the through holes 21. For example, typically, in the nozzle 1, the through holes 21 are arranged in an array (single or multiple rows). In addition to an array, any arrangement is possible, such as an arrangement in which multiple through holes 21 are arranged to form any shape, such as a circle or a star. The above-described through holes 21 have a funnel-shaped cross section along the ejection direction F. When the cross section along the ejection direction F is funnel-shaped, the laterally opposing edges of the through holes 21 may be curved or, as shown in FIG. 5 , may be linear.

[0040] In the examples shown in FIGS. 2 and 5 described above, both surfaces of the through hole 21, i.e., the surface where the inlet 22 opens and the surface where the outlet 23 opens, are flat. Alternatively, as shown in FIG. 11 , the through hole 21 may have a raised portion formed by deformation of the discharge plate 2 around the periphery of the through hole 21. For example, the discharge plate 2 may be deformed so that both the surface where the inlet 22 opens and the surface where the outlet 23 opens face the discharge direction F around the periphery of the through hole 21. Note that, even when the discharge pressure is increased to increase the discharge speed and discharge flow rate of the liquid L, it is preferable that the through hole 21 have flat both surfaces, as shown in FIGS. 2 and 5 , in order to further suppress coalescence of the discharged liquid L. As shown in FIG. 11 , if a raised portion is formed around the periphery of the through hole 21, the tip of the raised portion may be deformed by external force such as rubbing, which may make the discharged liquid more likely to spread or disperse.

[0041] A cleaning method using the nozzle 1 of the present invention configured as described above will now be described. The cleaning method using the nozzle 1 of the present invention is preferably performed by connecting the nozzle 1 to a liquid supply unit 20 filled with liquid L. For example, the nozzle 1 is connected to the liquid supply unit 20 that supplies the liquid L, and the liquid L is supplied to the liquid supply unit 20 by a known liquid supply means such as a constant-rate liquid delivery pump. The liquid L is then discharged in a straight line from the discharge ports 23 of each through-hole 21 in a discharge direction F. By applying the discharged liquid L to the area to be cleaned on the object to be cleaned, dirt on the surface of the object to be cleaned can be removed. Note that the liquid supply unit 20 is applied with pressure for discharging the liquid L under the control of a supply pump that constitutes the supply unit. This is preferably configured so that a predetermined amount of liquid L is continuously or discontinuously supplied toward the nozzle discharge port, or the supply can be stopped.

[0042] In the cleaning method using the nozzle 1 of the present invention, it is also preferable that the liquid L ejected from the through-holes 21 contact the area to be cleaned of the object to be cleaned in a state in which the liquid L comprises a substantially linear continuous flow. Furthermore, it is preferable that at a given moment during cleaning, the liquid L is continuously flowing from the outlet 23 to the area to be cleaned of the object to be cleaned without interruption (see FIGS. 7 and 8 ). By ejecting the liquid L from the through-holes 21 and contacting the surface S of the object to be cleaned in a state in which the liquid L comprises a substantially linear continuous flow, the liquid L can be accurately applied to the desired area, thereby efficiently cleaning the surface S of the object to be cleaned. This improves the linearity of the ejected liquid L, allowing the liquid L to be accurately applied to the dirt on the surface S of the object to be cleaned.

[0043] Here, the "substantially linear continuous flow" is a straight flow along the discharge direction F, and is the main discharge form of the liquid L immediately after being discharged from the through-hole 21. The liquid L discharged from the through-hole 21 may include one or more "substantially linear continuous flows," as well as liquid flows or droplets that are more intermittent than the continuous flows. The "substantially linear continuous flow" can be confirmed by the following method.

[0044] <Method for Confirming a Substantially Linear Continuous Flow> The nozzle is connected to a liquid supply unit with the discharge direction F aligned horizontally. Liquid L is supplied to the nozzle so that the discharge speed from the discharge port 23 is 10 m / sec or more and 40 m / sec or less, causing the liquid L to be discharged from the discharge port 23 of the through-hole 21. Five seconds after the start of discharge, an image of the liquid L being discharged from the nozzle 1 is taken. In the obtained image, a liquid flow along the discharge direction F from the through-hole 21 is selected, and the ratio J is calculated using the following formula. A liquid flow with a ratio J of 10 or more is defined as a "substantially linear continuous flow." Ratio J = Continuous length of liquid flow La / Width of liquid flow Wa The "continuous length of liquid flow La" is the maximum length of the continuous liquid flow between the discharge port 23 in the discharge direction F and a position P 30 mm away. The "width of liquid flow Wa" is the width of the liquid flow at the position P, which is the length perpendicular to the continuous direction of the liquid flow (discharge direction F).

[0045] In a cleaning method using the nozzle 1 of the present invention, from the viewpoint of suppressing damage to the object to be cleaned, it is preferable to set the distance between the discharge port 23 and the area to be cleaned to be 0.5 mm or more, more preferably 1 mm or more. From the viewpoint of further improving cleaning power, applying the liquid to the desired area with greater precision, and suppressing splashing of the liquid L to the surrounding area, it is preferable to set the distance between the discharge port 23 and the area to be cleaned to be 300 mm or less, more preferably 100 mm or less, even more preferably 50 mm or less, and particularly preferably 30 mm or less.

[0046] In the cleaning method using the nozzle 1 of the present invention, from the viewpoint of further improving cleaning power, it is preferable to set the ejection speed of the liquid L to preferably 10 m / sec or more, more preferably 12 m / sec or more, and even more preferably 15 m / sec or more. From the viewpoint of suppressing damage to the object to be cleaned and suppressing the liquid L from splashing around, it is preferable to set the ejection speed of the liquid L to preferably 40 m / sec or less, more preferably 35 m / sec or less, and even more preferably 30 m / sec or less. The ejection speed can be measured by the following method.

[0047] <Method of measuring the discharge rate> The liquid L is supplied to the nozzle, and the discharge flow rate (mm ３ / sec) was measured, and the flow rate was calculated based on the total area (mm ２ ) to obtain the discharge velocity (discharge flow rate of liquid per unit time / total area of ​​discharge ports 23). When the discharge plate 2 has a plurality of through-holes 21, the total area of ​​the discharge ports 23 is obtained by multiplying the area of ​​each discharge port 23 by the total number of discharge ports 23 (through-holes 21).

[0048] In the cleaning method using the nozzle 1 of the present invention, from the viewpoint of further improving cleaning power, it is preferable to set the supply pressure of the liquid L to preferably 0.05 MPa or more, more preferably 0.1 MPa or more. From the viewpoint of suppressing damage to the object to be cleaned, it is preferable to set the supply pressure of the liquid L to preferably 10 MPa or less, more preferably 5 MPa or less, and even more preferably 1 MPa or less. The supply pressure is the set pressure value of the supply pump.

[0049] From the viewpoint of further suppressing coalescence of the ejected liquid L and further improving cleaning power, the viscosity of the liquid L used in the present invention is preferably 0.5 mPa·s or more, more preferably 1 mPa·s or more. From the viewpoint of further improving ejection properties, the viscosity of the liquid L is preferably 40 mPa·s or less, more preferably 30 mPa·s or less. The viscosity of the liquid L described above is a value measured at 30°C using a B-type viscometer (TVB-10 type viscometer, manufactured by Toki Sangyo Co., Ltd.). The measurement conditions in this case are rotor No. M1, a rotation speed of 60 rpm, and a measurement time of 60 seconds.

[0050] In the cleaning method using the nozzle 1 of the present invention, the total discharge flow rate of the liquid L discharged from the nozzle 1 is preferably 10 mL / min or more, more preferably 20 mL / min or more, and even more preferably 40 mL / min or more, from the viewpoint of ensuring the amount of liquid L necessary for cleaning. Furthermore, from the viewpoint of preventing the liquid L from splashing around, the total discharge flow rate of the liquid L discharged from the nozzle 1 is preferably 1000 mL / min or less, more preferably 500 mL / min or less, and even more preferably 300 mL / min or less.

[0051] In the cleaning method using the nozzle 1 of the present invention, the discharge flow rate per through hole 21 is preferably 0.05 mL / min or more, more preferably 0.5 mL / min or more, and even more preferably 1.0 mL / min or more, from the viewpoint of ensuring the amount of liquid L necessary for cleaning. Furthermore, from the viewpoint of preventing the liquid L from splashing around, the discharge flow rate per through hole 21 is preferably 50 mL / min or less, more preferably 10 mL / min or less, and even more preferably 5 mL / min or less. The discharge flow rate per through hole 21 is an average value obtained by dividing the total discharge flow rate of the liquid L discharged from the nozzle 1 by the number of through holes 21.

[0052] In a cleaning method using the nozzle 1 of the present invention, from the viewpoint of further improving cleaning power, it is preferable to carry out the cleaning with a discharge load of the liquid L set to preferably 0.01 N or more, more preferably 0.1 N or more. From the viewpoint of suppressing damage to the object to be cleaned, it is preferable to carry out the cleaning with a discharge load of the liquid L set to preferably 1.0 N or less, more preferably 0.4 N or less. A method for measuring the discharge load will be explained in the examples below.

[0053] The liquid L used in the present invention may contain one or more components used in ordinary detergent compositions, provided that the effects of the present invention are not impaired. When the liquid L contains water, the water content is preferably 20% by mass or more, more preferably 40% by mass or more. A preferred example of the liquid L is a liquid containing a surfactant, for example, an aqueous liquid containing a surfactant at a critical micelle concentration or more.

[0054] Liquid L may contain one or more selected from water, surfactants, polyhydric alcohols, oils, polysaccharides, organic solvents, inorganic or organic salts, moisturizing ingredients, silicone derivatives, polyoxyalkylenes, pH adjusters, anti-inflammatory agents, disinfectants, preservatives, sequestering agents, antioxidants, UV absorbers, anionic polymers, nonionic polymers, amphoteric polymers, fragrances, thickeners, vitamins, and colorants. The silicone derivative may contain one or more selected from polyoxyalkylene-modified silicones. The polyoxyalkylene may contain polyethylene glycol / polypropylene glycol / polybutylene glycol-8 / 5 / 3 glycerin. The pH adjuster may contain one or more selected from acids and alkalis. The anti-inflammatory agent may contain one or more selected from glycyrrhetinic acid, glycyrrhizin, and derivatives thereof. The disinfectant may contain isopropylmethylphenol. The colorant may contain one or more selected from natural pigments and tar pigments.

[0055] The surfactant may include one or more selected from anionic surfactants, nonionic surfactants, amphoteric surfactants, and cationic surfactants. The polyhydric alcohol may include one or more selected from dihydric alcohols, trihydric or higher alcohols, sugars, and sugar alcohols. The oil may include one or more selected from linear or branched hydrocarbon oils, ester oils, and higher alcohols. The polysaccharide may include one or more selected from xanthan gum, cationized xanthan gum, diutan gum, welan gum, xylitol, erythritol, pullulan, and the like.

[0056] The organic solvent may include one or more selected from lower alcohols, aromatic alcohols, cellosolves, and carbitols. The lower alcohol may include one or two selected from ethanol and isopropyl alcohol. The aromatic alcohol may include one or two selected from benzyl alcohol and benzyloxyethanol. The cellosolve may include one or two selected from ethyl cellosolve and butyl cellosolve. The carbitol may include one or two selected from ethyl carbitol and butyl carbitol. The inorganic or organic salt may include one or two selected from sodium sulfate, sodium carbonate, sodium bicarbonate, potassium chloride, sodium chloride, magnesium chloride, and sodium citrate. The moisturizing component may include one or two or more selected from sugars and derivatives thereof, amino acids and derivatives thereof, animal and plant protein derivatives, and animal and plant extracts.

[0057] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0058] Examples 1 to 9 Nozzles having a configuration similar to that of the nozzle 1 shown in FIG. 1 were manufactured. The through holes 21 of the nozzles were arranged in the same pattern as that shown in FIG. 3. In Examples 1 to 9, the inner diameters of the outlet and inlet of each through hole 21 of the nozzle, the length of the outlet flow path formed by the through holes 21, the number N of through holes per unit area, and the area ratio of the through hole arrangement region 21R in the outlet plate 2 were varied as shown in Table 1. All through holes 21 had a tapered shape in which the inner diameter decreased in the direction of liquid ejection. More specifically, the pair of tapered edges 21a, 21b of the through hole 21 were curved edges that curved toward the central axis of the outlet 23 throughout the entire area in the ejection direction from the inlet to the outlet (see FIG. 2(a)). The number N of through holes per unit area was calculated using the method described above. The substrate sheet used was a sheet containing 100% by mass of polyethylene terephthalate, a thermoplastic resin, and the substrate sheet was laser processed from the side where the inlet was formed to form the discharge plate 2. The base 4 was manufactured using the same material as the discharge plate 2. The discharge plate 2 was joined to the large-diameter cylinder 46 of this base 4 by heat fusion. In the obtained nozzle 1, the inner diameter of the through-hole 21 in the discharge plate 2 decreased in the discharge direction.

[0059] Comparative Example 1 The nozzle plate 2 of Example 1 was inverted and joined to the large-diameter cylinder 46. That is, the nozzle plate 2 was joined so that the inner diameter of the through-hole 21 had an inverse tapered shape, increasing in the direction of discharge. Apart from this, a nozzle was manufactured in the same manner as in Example 1.

[0060] [Comparative Examples 2 and 3] Nozzles were prepared having through holes with a constant inner diameter and a straight shape in cross section. In Comparative Example 2, a nozzle with two through holes was prepared, and in Comparative Example 3, a nozzle with one through hole was prepared. In Table 1, "-" indicates that no evaluation was performed. [Comparative Examples 4 and 5] Nozzles were manufactured using the same method as Comparative Example 1, except that a sheet containing 100% by mass of polylactic acid was used as the thermoplastic resin. Table 1 shows the thickness of the nozzle at the portion where the through holes were formed, as the length of the discharge flow path formed by the through holes 21. [Comparative Example 6] A nozzle was manufactured using the same method as Example 1, except that the inner diameter of the discharge port was 250 μm.

[0061] [Evaluation of Straightness] The nozzles obtained in the Examples and Comparative Examples were evaluated for straightness, i.e., whether they could accurately apply the liquid to the object to be cleaned, using the following method. A syringe with a capacity of 1 mL or more was prepared as a liquid supply unit. Water was used as the liquid. The syringe was filled with water, and the nozzles obtained in the Examples and Comparative Examples were connected to the tip of the syringe. Water was ejected so that the ejection direction was parallel to the horizontal. The ejection operation was performed so that the ejection speed was 10 m / sec or more. The liquid was photographed 5 seconds after ejection, and the inclinations of five water streams randomly selected from the image were calculated. The average value was taken as the inclination of the water stream, and the straightness was evaluated according to the following criteria. The inclination of the water stream refers to the angle between the water stream and a line parallel to the horizontal, where the line is set to 0°. Evaluation criteria A: The inclination of the water flow is less than 15 degrees. B: The inclination of the water flow is 15 degrees or more but less than 30 degrees. C: The inclination of the water flow is 30 degrees or more.

[0062]

[0063] As is clear from the results shown in Table 1, when the through-hole has a tapered shape in which the inner diameter decreases in the direction of liquid ejection and the inner diameter of the ejection port is 10 μm or more and 200 μm or less, the ejected liquid has excellent straightness. This suppresses the diffusion of the water flow and is expected to accurately direct multiple water streams to the desired position on the area to be cleaned. Note that while the nozzle of Comparative Example 6 was rated A for straightness (see Table 1), each Example was superior to the nozzle of Comparative Example 6 in terms of splashing of liquid L during cleaning and damage to the area to be cleaned (see, for example, Tests 10 and 15 in Table 4).

[0064] [Tests 1 to 17 on Skin Cleansing] The nozzles obtained in Examples 1, 2, 4 to 9, and Comparative Examples 1, 2, and 4 to 6 were evaluated for cleansing ability and damage to the area to be cleaned using the following methods. Specifically, achieving both [evaluation of cleansing ability] and [evaluation of splashing of liquid during cleaning] demonstrated that the nozzles could efficiently clean dirt from the surface of the object to be cleaned, and that the nozzles were excellent in [evaluation of damage to the area to be cleaned], demonstrating excellent safety.

[0065] Area to be cleaned: A 30 mm square area of ​​skin on the inner side of a human forearm was used as the area to be cleaned. The skin color Ea of bare skin before application of the model comedo sebum and before cleaning was measured using a spectrophotometer (Konica Minolta, Inc., "CM-600d"). Formation of model stain: A model comedo sebum with the composition shown in Table 2, in which carbon black was dispersed, was prepared. 30 μg of model comedo sebum was applied to the area to be cleaned, and then excess model comedo sebum from the surface was scraped off six times with a 15 mm wide spatula. The model comedo sebum remaining on the area to be cleaned was allowed to dry for 30 minutes to form the model stain. After the model stain was formed, the skin color Eb (100% value) after the model stain was formed was measured in the same manner using the spectrophotometer. Cleaning method: The nozzle obtained in the Examples and Comparative Examples was connected to a liquid supply unit for supplying liquid. The nozzle was moved so that the liquid L ejected from the nozzle hit the entire target area evenly, and the area was cleaned for 10 seconds to remove dirt. When cleaning using the nozzle obtained in each example, the liquid L ejected from the through-hole 21 contacted the target area of ​​the object to be cleaned in the form of a substantially linear continuous flow. A sensory evaluation of the sensation of use was performed based on the pain felt when the liquid L hit the target area. The distance between the ejection port and the target area was 5 mm. The ejection speed, supply pressure, state of the ejected liquid, and proportion J of the liquid L are shown in Tables 3 and 4. The proportion J was calculated according to the method described above. In Tests 1 to 16, an aqueous solution containing 2% by mass of a surfactant (polyoxyethylene (2) lauryl ether sodium sulfate, "EMAL 227" manufactured by Kao Corporation) was used as the liquid L. In Test 17, an aqueous solution containing 2% by mass of a surfactant (polyoxyethylene sorbitan monolaurate (20E.O.), "Rheodor TW-L120" manufactured by Kao Corporation) was used as liquid L. Subsequently, the area to be cleaned was rinsed by pouring 40 mL of tap water over it. It was then air-dried. The skin color Ec of the area to be cleaned after air-drying was measured in the same manner using the spectrophotometer described above, and this was taken as the skin color Ec after cleansing.

[0066] The viscosity of the undiluted Liquid L used in Tests 1 to 16 was 2.5 mPa s at 30° C. The viscosity of the undiluted Liquid L used in Test 17 was 2.9 mPa s at 30° C. The viscosity of the undiluted Liquid L was measured using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd., TVB-10 model viscometer, measurement conditions: rotor No. M1, 60 rpm, 30° C., 60 seconds).

[0067]

[0068]

[0069]

[0070] [Total Discharge Flow Rate] The mass of the liquid L discharged from the nozzle is measured, and the mass is divided by the specific gravity of the liquid L and the discharge time, and the value converted to a value per unit time (min) is taken as the total discharge flow rate. The discharge time is 10 seconds.

[0071] [Evaluation of cleansing ability] Cleansing ability was evaluated on a four-point scale based on the cleansing rate E obtained by the following formula: Cleansing rate E (%) = [1 - (bare skin color Ea - skin color after cleansing Ec) / (bare skin color Ea - skin color after model stain formation Eb)] x 100 Evaluation criteria A: Cleansing rate E is 80% or more. B: Cleansing rate E is 60% or more and less than 80%. C: Cleansing rate E is 40% or more and less than 60%. D: Cleansing rate E is less than 40%.

[0072] [Evaluation of liquid splashing during cleaning] For the nozzles obtained in Examples 1, 2, 4 to 9, and Comparative Examples 1, 2, and 4 to 6, liquid splashing during cleaning was evaluated using the following method. Bioskin (manufactured by Beaulux, cheek skin model, Φ50 mm) was attached to the center of a piece of drawing paper (2912 mm x 3084 mm) with double-sided tape. The nozzles obtained in the Examples and Comparative Examples were connected to a liquid supply unit that supplies liquid. The liquid ejected from the nozzle was applied to the center of the Bioskin for 10 seconds. The distance from the nozzle to the center of the Bioskin was 5 mm.

[0073] The liquid that had splashed around before hitting the Bioskin and the liquid L that had splashed around after hitting the Bioskin were observed. The distance S between the center of the Bioskin and the liquid L that had splashed to the farthest point from the center of the Bioskin and adhered to the drawing paper was measured. The shorter the distance S, the less liquid splashed during cleaning.

[0074] [Evaluation of damage to the area to be cleansed] The pain felt when the liquid flow hit the skin of the area to be cleansed was evaluated sensorily according to the three-level scale described below. These evaluations were carried out by two Japanese women in their 30s and 40s. In cases where the evaluation results of the two women differed, the evaluation result of the person who felt more pain is shown. Evaluation criteria A: Almost no pain felt B: Slight pain felt C: Pain felt

[0075] [Tests 18 to 20 for Oral Cleaning] The nozzles obtained in Examples 2, 3, and Comparative Example 3 were evaluated for cleansing performance and safety using the following methods. Specifically, the nozzles achieved both excellent results in [Model Plaque Removal Performance Evaluation] and small values ​​in [Evaluation by Discharge Load Measurement], indicating efficient cleaning of dirt from the surface of the object to be cleaned. The nozzles also demonstrated excellent safety through excellent results in [Evaluation of Usability When a Liquid Flow is Directed against Teeth or Gums]. The [Total Discharge Flow Rate] was calculated as described above. [Evaluation of Model Plaque Removal Performance] Artificial plaque (model-specific artificial plaque) manufactured by Nissin Co., Ltd. was uniformly applied to the surface of a circular area (10 mm in diameter) on a flat acrylic plate. After leaving the plate for approximately 5 minutes, liquid was discharged from each nozzle so as to direct a water flow toward the artificial plaque, and cleansing performance was evaluated. The measurement conditions were: distance between the nozzle and the area to be cleaned: 10 mm, discharge time: 5 seconds, liquid: water, and discharge pressure: 0.5 MPa. The cleansing performance evaluation criteria were as follows. The results are shown in Table 5. To evaluate the cleansing ability, the area where the artificial plaque had been applied after cleaning was photographed with a digital camera. The image obtained was analyzed using image analysis software WinROOF to determine the area of ​​the artificial plaque that had been cleaned.

[0076] The nozzles obtained in Example 2, Example 3, and Comparative Example 3 were evaluated for damage to the area to be cleaned using the following method. [Evaluation of the feeling of use when the liquid flow is applied to the teeth or gums] Eight adults in their 30s to 50s served as subjects. They were asked to clean their teeth or gums using each of the nozzles of Example 2, Example 3, and Comparative Example 3. They were asked to evaluate the feeling of use when the liquid flow was applied. The cleaning conditions were: discharge distance: 10 mm, discharge time: 5 seconds, liquid: water, discharge pressure: 0.5 MPa. The evaluation was based on a majority vote of the highest score (evaluation result) obtained by each subject, and the evaluation criteria were as follows. The results are shown in Table 5. A: There was little irritation to the gums, and the contact felt comfortable when used. B: There was some irritation to the gums. C: There was strong irritation to the gums.

[0077] [Evaluation by Discharge Load Measurement] A flat plate (40 mm x 40 mm) was attached to the tip of the measuring part of a digital force gauge (ZTS-20N manufactured by Imada Co., Ltd.). The maximum discharge load was measured when a water jet was discharged from the nozzles obtained in Example 2, Example 3, and Comparative Example 3. The measurement conditions were discharge distance: 10 mm, discharge time: 5 s, liquid: water, and discharge pressure: 0.5 MPa. With the discharge direction F aligned vertically, the water jet was discharged from the nozzle toward the flat plate. The load was measured. The results are shown in Table 5.

[0078]

[0079] As is clear from the results shown in Tables 3 to 5, the nozzles of Examples 1 to 9 ejected water with a more straight-line flow than the nozzles of Comparative Examples 1 to 5, allowing the water flow to be accurately directed at the area to be cleaned. Furthermore, in addition to excellent cleansing performance, there was less splashing of Liquid L, minimizing the impact on areas other than the area to be cleaned. Consequently, damage to the area to be cleaned was reduced. The nozzles of Examples 1 to 9 were evaluated as having the same straight-line flow as Comparative Example 6, but there was less splashing of Liquid L. These results demonstrate that the nozzles of the present invention and the cleaning methods using these nozzles can accurately direct the ejected liquid at dirt on the surface of the object to be cleaned, allowing for safe and efficient cleaning of dirt from the surface of the object to be cleaned.

[0080] According to the present invention, it is possible to provide a liquid discharge nozzle for cleaning that can accurately apply the discharged liquid to dirt on the surface of the object to be cleaned, and can safely and efficiently clean the dirt on the surface of the object to be cleaned.

Claims

1. A cleaning liquid discharge nozzle having a discharge plate with one or more through holes through which liquid is discharged, the through holes having a tapered shape in which the inner diameter decreases in the direction of liquid discharge, and the inner diameter of the discharge outlet in the through hole is 10 μm or more and 200 μm or less.

2. The cleaning liquid discharge nozzle according to claim 1, wherein the inner diameter of the discharge port is 20 μm or more and 150 μm or less, preferably 20 μm or more and 110 μm or less.

3. A cleaning liquid discharge nozzle according to claim 1 or 2, wherein the inner diameter of the inlet of the through hole is 20 μm or more and 500 μm or less, preferably 50 μm or more and 400 μm or less, and more preferably 50 μm or more and 350 μm or less.

4. A cleaning liquid discharge nozzle according to any one of claims 1 to 3, wherein the ratio of the inner diameter of the discharge outlet to the inner diameter of the inlet in the through hole is greater than 1.0 and not greater than 40, preferably 1.1 or greater and 20 or less, and more preferably 1.5 or greater and 10 or less.

5. A cleaning liquid discharge nozzle according to any one of claims 1 to 4, wherein the length of the discharge flow path formed by the through holes is 100 μm or more and 3000 μm or less, preferably 200 μm or more and 2000 μm or less, and more preferably 200 μm or more and 1000 μm or less.

6. The cleaning liquid discharge nozzle according to any one of claims 1 to 5, wherein the discharge plate includes a thermoplastic resin.

7. A cleaning liquid discharge nozzle according to any one of claims 1 to 6, wherein the liquid discharge nozzle preferably contains a thermoplastic resin in an amount of 50% by mass or more, preferably 50% by mass or more and 100% by mass or less, and more preferably 70% by mass or more and 100% by mass or less, based on the total mass of the nozzle.

8. The unit area (1 cm) of the discharge plate ２ The number of through holes per square centimeter is 20 per square centimeter. ２ More than 1500 pieces / cm ２ Preferably 50 or less per cm ２ More than 1000 pieces / cm ２ More preferably, 100 particles / cm or less ２ More than 500 pieces / cm ２ The cleaning liquid discharge nozzle according to any one of claims 1 to 7, wherein:

9. A cleaning liquid discharge nozzle according to any one of claims 1 to 8, wherein the liquid discharge nozzle comprises a cylindrical base in which a large diameter cylinder and a small diameter cylinder having an inner diameter smaller than that of the large diameter cylinder are connected together, the small diameter cylinder is connected to one axial side of the large diameter cylinder, and the opening of the large diameter cylinder on the opposite side of the axial direction from the small diameter cylinder is closed by the discharge plate.

10. A liquid discharge nozzle for cleaning according to claim 9, wherein a supply pump for supplying liquid is connected to the end of the small diameter cylinder opposite to the end of the large diameter cylinder in the axial direction.

11. A liquid discharge nozzle for cleaning as described in claim 9 or 10, wherein the internal spaces of the large diameter cylinder and the small diameter cylinder communicate with each other in the discharge direction, and the internal spaces form a flow path for the liquid.

12. A cleaning liquid discharge nozzle according to any one of claims 9 to 11, wherein the small diameter cylinder is longer in the discharge direction than the large diameter cylinder.

13. A cleaning liquid discharge nozzle according to any one of claims 1 to 12, wherein the cross-sectional shape of the through-hole along the discharge direction has a pair of tapered edges that extend so as to converge towards the central axis of the discharge port, and the pair of tapered edges are curved edges that curve towards the central axis of the discharge port.

14. A cleaning liquid discharge nozzle according to any one of claims 1 to 13, wherein the through hole has a tapered shape over the entire area in the discharge direction from the inlet to the discharge outlet.

15. A cleaning liquid discharge nozzle according to any one of claims 1 to 13, wherein the through hole has a tapered portion and a non-tapered portion, the tapered portion being formed closer to the discharge port than the non-tapered portion.

16. A cleaning liquid discharge nozzle as described in any one of claims 1 to 15, wherein when the liquid discharge nozzle is viewed in a plane, the distance between the centers of adjacent through holes is 0.1 mm or more and 3 mm or less, preferably 0.2 mm or more and 2 mm or less.

17. A liquid discharge nozzle for cleaning described in any one of claims 1 to 16, wherein when the liquid discharge nozzle is used to cleanse skin, the inner diameter of the discharge port is 15 μm or more and 100 μm or less, preferably 20 μm or more and 80 μm or less, more preferably 30 μm or more and 70 μm or less, and even more preferably 40 μm or more and 60 μm or less.

18. A liquid discharge nozzle for cleaning described in any one of claims 1 to 17, wherein when the liquid discharge nozzle is used to cleanse skin, the inner diameter of the inlet of the through hole is 20 μm or more and 500 μm or less, preferably 100 μm or more and 400 μm or less, more preferably 150 μm or more and 350 μm or less, and even more preferably 200 μm or more and 350 μm or less.

19. A liquid discharge nozzle for cleaning described in any one of claims 1 to 16, wherein when the liquid discharge nozzle is used to clean the oral cavity, the inner diameter of the discharge outlet is 50 μm or more and 200 μm or less, preferably 60 μm or more and 150 μm or less, and more preferably 70 μm or more and 130 μm or less.

20. A liquid discharge nozzle for cleaning described in any one of claims 1 to 16 or 19, wherein when the liquid discharge nozzle is used to clean the oral cavity, the inner diameter of the inlet of the through hole is 70 μm or more and 700 μm or less, preferably 100 μm or more and 400 μm or less, more preferably 150 μm or more and 350 μm or less, and even more preferably 200 μm or more and 350 μm or less.

21. A cleaning liquid discharge nozzle according to any one of claims 1 to 20, wherein the discharge plate is a flat plate or a curved plate that is curved in whole or in part.

22. A cleaning liquid discharge nozzle according to any one of claims 1 to 21, wherein the front or back surface of the discharge plate is a smooth surface or an uneven surface.

23. A cleaning liquid discharge nozzle according to any one of claims 1 to 22, wherein the discharge plate has a through-hole arrangement region in which the through-holes are formed and a non-through-hole arrangement region in which the through-holes are not formed, and the area ratio of the through-hole arrangement region to the discharge plate is preferably 10% or more and 100% or less, more preferably 50% or more and 80% or less.

24. A cleaning method using a cleaning liquid discharge nozzle according to any one of claims 1 to 23, wherein a liquid is discharged from the discharge port of the through-hole and directed at a part of the object to be cleaned, thereby removing dirt from the surface of the object to be cleaned.

25. A cleaning method according to claim 24, in which the distance between the discharge port and the area to be cleaned is set to 0.5 mm or more and 300 mm or less, preferably 1 mm or more and 100 mm or less, more preferably 1 mm or more and 50 mm or less, and even more preferably 1 mm or more and 30 mm or less, to remove dirt from the surface of the object to be cleaned.

26. A cleaning method according to claim 24 or 25, in which the liquid is ejected at a speed of 10 m / sec or more and 40 m / sec or less, preferably 12 m / sec or more and 35 m / sec or less, and more preferably 15 m / sec or more and 30 m / sec or less, to remove dirt from the surface of the object to be cleaned.

27. A cleaning method according to any one of claims 24 to 26, in which the liquid supply pressure is set to 0.05 MPa or more and 10 MPa or less, preferably 0.1 MPa or more and 5 MPa or less, and more preferably 0.1 MPa or more and 1 MPa or less to remove dirt from the surface of the object to be cleaned.

28. A cleaning method according to any one of claims 24 to 27, wherein the liquid discharged from the through-hole is brought into contact with the part to be cleaned of the object to be cleaned in a state including one or more continuous flows.

29. A cleaning method according to any one of claims 24 to 28, wherein the liquid discharged from the through-hole is brought into contact with the part to be cleaned of the object to be cleaned in a state where the liquid comprises a substantially linear continuous flow.

30. The cleaning method according to claim 29, wherein the substantially linear continuous flow has a ratio J expressed by the following formula of 10 or more: Ratio J = Continuous length of liquid flow / Width of liquid flow 31. A cleaning method according to any one of claims 24 to 30, wherein the viscosity of the liquid is 0.5 mPa·s or more and 40 mPa·s or less, preferably 1 mPa·s or more and 30 mPa·s or less.

32. A cleaning method according to any one of claims 24 to 31, wherein the total discharge flow rate of the liquid is 10 mL / min or more and 1000 mL / min or less, preferably 20 mL / min or more and 500 mL / min or less, and more preferably 40 mL / min or more and 300 mL / min or less.

33. A cleaning method according to any one of claims 24 to 32, wherein the area to be cleaned is one or more selected from keratinous materials and teeth.

34. A cleaning method according to claim 33, wherein the keratinous material includes one or more areas selected from skin, scalp, hair, and nails, and preferably the skin includes skin in one or more areas selected from face, arms, hands, feet, and back, and the liquid discharge nozzle has a flow path for the liquid therein.

35. Use of the liquid discharge nozzle according to any one of claims 1 to 23 for removing dirt from the surface of an object to be cleaned.

Images