CA2234446A1 - High pressure swirl atomizer - Google Patents

Abstract

An atomizing nozzle having a plurality of vanes, a swirl chamber, and a discharge orifice is provided for dispensing a liquid spray. The plurality of vanes extend outwardly from the swirl chamber and are in fluid communication therewith. The discharge orifice is generally concentric and in fluid communication with the swirl chamber. The atomizing nozzle provides a fine atomized spray when used in manually-actuated pump type dispensers.

Description

CA 02234446 l998-04-09 W O 97/13S84 PCT~US96/16427 E~GH PRESSURE SWIRL ATOMIZER

TECHNICAL FIELD
The present invention relates generally to the field of fluid ~tQmi7~tion, and more particularly to an improved fluid ~loll~llg nozzle for use in m~ml~lly-~ctll~ted pump dispensers which is capable of generating a fine liquid spray.

BACKGROIJND OF THE INVENTION
Fluid atomizing nozzles are widely used in applications for dispensing of various consumer hygiene, health, and beauty care products (e.g., hair spray dispensers, aerosoi deodorant spray dispensers, nasal spray dispensers and the like).
More specifically, devices incorporating fluid atomizing nozzles for dispensing conc~mPr products are generally of either the m~n-~lly_~ct~-~ted pump type or the aerosol type. Manually-act~ted pump dispensers typically include a piston and cylinder arr~ngpmpnt which converts force input by the user (e.g., sq--eP7ing a pump lever or depress.l g a finger button) into fluid pressure for atomizing the liquid product to be tlicrçn.ced The liquid product is generally directed into an atomizing nozzle having a swirl c~l~mbP,r where the rotating fluid forms a thin conical sheet which breaks into lip~...e~.ls and discrete particles or drops upon exiting to the ambient en~;.on.n~
Aerosol dispensers, on the other hand, typically incorporate a pressurized gas (e.g., generally a form of propane, isobutane or the like) which is soluble with the liquid product to aid in ~lo...;~;Qn. When the liquid product is dischal~ed from the p~n.cç~, much in the same manner as with a m~n~qlly actu~ted dispenser, the gas "flashes off'' (i.e., sepal~l~s out ofthe liquid and returns to its gaseous state), thereby ~c~ictinS~ the ~lon,~alion process by causing some of the liquid to break apart into i~,iq.n~...lc and discrete particles or drops. Thus, the liquid in an aerosol type ~1icpencPr is atc.l-"~ed by both the phase change of the pressurized gas as well as by the ~wi lin~ motion of the liquid as it exits the swirl cl.~...l,çr. It has been found, however, that aerosol propellants are often not plefe..cd such as for reasons ofen~i.on.n~ l concellls for PY~mrle Nozzles desi~P,d for operation with an aerosol ~ dispenser, however, will generally not produce the same spray characteristics when adapted for use in a m~n-l~lly ~c~tl~ted pump dispenser.
The spray characteristics of an aloll~i-,g nozzle (e.g., drop size, spray angle,spray penetration and p~ alion) can be illlpOI l~ll for achieving consumer s~ticf~ction with a dispellscd product. For ~ ~A...rlç7 in hair spray applications, it can CA 02234446 l998-04-09 W O 97/13584 PCT~US96/16427 be advantageous to generate a spray having a smaller mean particle size (e.g., generally about 40 microns), as sprays with larger particle sizes may create a perceptively "wet" or "sticky" spray because the drying time for the larger particles is co..es~,ondingly longer. One method for decreasing an atomized spray's mean particle size is to increase the liquid pressure, which, in turn, increases the angular velocity of the liquid within the swirl chamber and generally results in a thinner film and hence a finer spray. However, because the required increase in pressure mustgenerally be accomplished in a m~n~lly-~ctll~ted pump r~i~p~n~er by increasing the hand ~rt~tion force, this type of ~ pen.eer may be less desirable to consumers because of the increased effort required for its operation. Consequently, an atomizing nozzle which can generate a spray having the desired mean particle size of about 4G microns with the lowest possible hand ~chl~tion force would be desirable for use in m~nll~lly-act~l~ted pump dispensers. Heretofore, this combination of features has not been available.
The spray characteristics of an atomizing nozzle are generally a function of the viscosity of the liquid to be ~icp~n.~ed, the pressure of the liquid, and the ~eo.,.el.~ of the alo,-li~-,g nozzle (e.g., orifice ~ meter, swirl chamber ~ meter~
vane cross section~l areas and the like). The prior art in the fluid i.lo~ g industry close~ a variety of fluid atomizing nozzles for use in m~ml~lly-actll~ted pump dh,l~ense-, or, in aerosol dispensers, in which these parameters have been co.nbilled to achieve specific spray characteristics. For example, commercially available lQ~ g nozzles may be adapted for use in m~ml~lly-~r.tl-~ted pump dispensers of co~.. er products. The con~lne-Gial alo.. i~ing nozzles of which the applicant is aware are generally co,-.l..ised of a plurality of generatly radial vanes which exit into a swirl Ch~ /G. being generally concentric with a dischalge orifice. These known ~lo...;,;n~ nozzles typically have a swirl chamber rli~n ete~ in a range of between about 0.75 mm and about 1.5 mrn, an individual vane exit area in a range of bet~,veen about 0.045 mm and about 0.20 mm, and a discharge orifice di~mPter in a range ofbetween about 0.25 mm and about 0.50 rnm. It has, however, been observed by the applicant that in order for these alo--.~--g nozzles to form a spray having the desired 40 micron particle size, fluid inlet pressures greater than or equal to 200 psig are required.
In the patent area, U.S. Patent No. 4,979,678 to Ruscitti et al. discloses an ~o-n;,;.~g nozzle having a series of spiral turbulence Gh~nn~ which exit into a turbulence cl.a---ber that is coaxial with the nozzle exit orifice. U.S. Patent No.
5,269,495 to Dobbeling similarly illustrates a high pressure atomizer having a liquid feed ~nmllu~, a plurality of straight radial supply ducts, and a turbulence chamber W O 97/13584 PCT~US96/16427 with an exit orifice. The liquid enters the turbulence chamber through the radial supply ducts where it impinges upon liquid e-lLtli,.g from an opposing turbulence duct. This impingPmPnt is to create a "shearing action" which allegedly atomizes the liquid. This atomizer, however, is taught as requiring, inlet fluid pressures appro~ching 2200 psig to achieve this "shearing" effect.
While the above rli~c~ ed prior atomizing nozzles may function generally s~ficf~tQrily for the purposes for which they were ~e~igner~, it is desirable to provide an improved ato~ * nozzle with structural and operational advantages of finer spray characteristics with convenient and effiri~nt manual activation. Heretofore there has not been available an atol.~--g nozzle for use in a m~n~ y-actl~ted pump dispenser having a simple, easily m~n--f~ctl-rably swirl chamber and vanes whichwould be capable of producing an atolui~ed liquid spray having a 40 micron or less mean particle size with a required activation liquid pressure generally below 200 psig.

SUMMARY OF THE INVENTION
An ato--fi~-* nozzle is provided which is capable of producing a spray of liquid product having about a 40 micron particle size with an activation liquid pressure of about 160 psig. The ~lo...;~ nozzle comprises a supply structure fortransporting a pressurized liquid from a co..la;-lel, a plurality of generally radial vanes, a swirl chamber having a chamber ~ mP~ter~ and a discharge orifice having an orifice ~ mptçr.
The plurality of vanes are in fluid communication with the swirl chamber and have a generally decreasing individual vane cross sectional area toward the swirl .h~...l-r,r. The swirl cl~ -bPr is similarly in fluid cQmmlln;~tiQn with the discha-ge orifice for releasing an atomized liquid product to the ambient environment The plurality of vanes pler~-~bly have a c~m~ five vane exit area being in a range of between about 0.18 mm2 and about 0.36 mm2 in combination with a swirl rll~mhPr ...e~e. of between about 1.3 mm and about 2.0 mm. It is more p,er~,.ed, however,that the plurality of vanes con~i~tC of three vanes with each vane having an individual vane exit area being in a range of between about 0.06 mm2 and about 0.12 mm2, and with the discharge orifice having an orifice .I;h.... lP- being about 0.35 mm.

BRIl~F DESCRIPTION OF THE DRAWINGS
While the speçifir~ti~rl cQnr~ es with claims particularly pointing out and ~lictin~.tly rl~imin~ the present invention, it is believed the same will be better understood from the following description taken in conj~lnction with the accol.lpal.j~ng drawings in which:

CA 02234446 l998-04-09 W O 97/13584 PCTrUS96/16427 FIG. 1 is an enlarged cross sectional view of an atomizing nozzle made in accordance with the present invention;
FIG. 2 is an enlarged cross sectional view of the nozzle body of FIG. 1, illustrated without its nozzle insert for clarity;
FIG. 3 is a rear elevational view of the nozzle insert of the ato~ .g nozzle ofFIG. l;
FIG. 4 is an enlarged cross sectional view ofthe nozzle insert in FIG. 3, taken along line 4-4 thereof;
FIG. 5 is a graphical illustration of the general relationship between swirl cll~--ber ~i~mepr and individual vane exit area in an ~tO~ 7;l~g nozzle; and FIG. 6 is a graphical illustration of the general rel~tionchip between liquid pressure and mean particle size of an atomizing nozzle of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the present l~.eÇt:.. t;d embodiments ofthe invention, an example of which is illustrated in the acco--lpal.ying drawings wherein like numerals in-iir~te the same ~ nl~ont~ throughout the views. FIG. 1 is an enlarged cross secti~ n~l view of an ~tomi7ing nozzle 15 made in accordance with the present invention for use in a m~m-~lly-~ctu~tecl pump type liquid product dispenser.
.At~mi~ing nozzle 15 comprises a nozzle body 20 and a nozzle insert 21. As best illustrated in FIGS. 1 and 2, nozzle body 20 can ~refe,ably be provided with a generally cylindrically shaped interior and may have various external configurations or structures which may aid the user in operation of the dispenser (e.g., raisedpin~, surfaces, dep-tss;ons for finger pl~c~mf~nt and the like). Nozzle body 20 is further illustrated as inrlllding nozzle feed p~c~ge 22 disposed therein for receiving feed tube 23, such as by a frictional i..le,rel~nce fit between passage 22 and feed tube outer surface 24. The frictiona1 co.~eclion, more commrJnly known as a press fit, ,en feed tube outer surface 24 and nozzle feed passage 22 can p-t;re,ably b snug but removable to f~rilit~te cl~ g or rinsing of debris which may otherwise build up and clog the atc,...,~ g nozzle.
~ ;re.~bly, the co~ onding surfaces of nozzle feed passage 22 and feed tube outer surface 24 are provided of approp.iale size and material to effectively create a seal therebetween so that there will be generally no liquid flow between the surfaces when the di~pens~r is in operation. Although it is pt~;r~-led that nozzle feed tube 23 be r~;lained by simple frictional interaction with nozzle feed passage 22, it will be understood by one skilled in the art that feed tube 23 may be connected to nozzle feed passage 22 by alternate means such as adhesive connections, welding, CA 02234446 l998-04-09 W O 97/13584 PCT~US9G/16427 merh~nical connectin~ structures (e g, threads, tabs, slots, or the like), or by integral m~nllf~chlre with nozzle passage 22.
Feed tube 23 is to provide fluid comm~miC~tion with a suitable liquid storage container (not shown) so that the liquid product to be ~iepPneed may be L.~.ls~-o.led from the container to ato-- ~ing nozzle 15 Feed tube 23 may ,ol~re,~bly form part of a valve stem for a conventional piston and cylinder ~l~'~g~ ~ ~nt or other dispensing arr~ngPmPnt (not shown) which generates the liquid pressure required for operation of atomizing nozzle 15.
A generally plug-shaped insert post 26 is preferably disposed a~ cPnt feed tube 23, as best illustrated in FIGS. 1 and 2. Insert post 26 p~Çt;~bly has a s~1bst~nti~lly planar end surface 28 a~ cPnt its distal end, and insert post surface 30 End surface 28 is generally circular shaped when viewed from the direction indicated by the arrow in FIG. 2 Insert post 26 can be a separate structure which may be ~tt~çheci to nozzle body 20 by a meçh~nic~l means (e.g, threaded, press fit or the lilce), but will preferably be integrally formed with nozzle body 20 for ~eimrli~ity of m~nllf~ctllre (such as by injection molding) Supply cha...l)el 32 generally forms an annulus which is bounded by post surface 30 and inside wall 34 P,ert:l~bly, supply . h~ ~he 32 is a~ c~nt to and in fluid comm~-niC~tion with feed tube 23 to initially receive fluid from the storage container.
As best seen in FIGS 3 and 4, nozzle insert 21 is p-ert-~ly generally cup-shaped, having a cavity 38 with a cavity surface 39 and an end face 40 Located CPnt to end face 40 and generally CQI~'e~lniC with the cenle-line of 38 is swirlchamber 42, illustrated with a ch~..k di~mpter CD Swirl chamber 42 preferably has a generally conical shape for flow Pffi~i~ncy (i.e, minim~l pressure drop), though other commoll co,~"--a~ions such as bore shapes may also be sl it~bl~
A discharge orifice 44 having a predGIt..,~ned orifice di~metPr (OD) is preferably located ~djacPnt to and generally conce.l~-ic with swirl chamber 42.
Disch~ye orifice 44 thereby provides fluid comm~niG~tion between swirl chamber 42 and the ~llb-'t ~t en~/iro,l---e--~. As best illustrated in FIG 3, a plurality of grooves 46 are preferably disposed on end face 40 PYt~n-ling generally radially inward fromcavity surface 39 to conical swirl ch~mhf~r 42 In a p.er~l.ed embodiment, each groove 46 connecl~ generally tangentially with swirl chamber 42 and nozzle insert 36 has at least two spaced grooves 46. In the embodiment shown, nozzle insert 36 has three grooves 46 disposed generally radially and eqlli~iet~nt about swirl chamber 42, as best illustrated in FIG. 3.
The inside wall 34 of supply chan.l)e. 32 is preferably sized to receive and frictionally retain nozzle insert 21. Alternatively, nozzle insert 21 may include a ring CA 02234446 l998-04-09 W O 97/13584 PCTrUS96/16427 or other locking device (not shown) for m.och~nically mating with a sl~t or similar structure corresponding with the locking device (not shown) and disposed about inside wall 34 so that nozzle insert 21 will be positively retained within nozzle body 20. Preferably, the surfaces of inside wall 34 and insert surface 37 are sized such that when assembled in contact with each other, they will create an effective seal and there will be generally no liquid flow between the surfaces when the dispenser is in operation.
When nozzle insert 21 has been fully assembled with inside wall 34 of nozzle body 20 such that end surface 28 and end face 40 are in contact (as best illustrated in FIG. 1), a plurality of generally lec~ P,~l~r vanes 48 and a supply ~nmllll~ 50 are ned Supply ~nmllll~ 50 is preferably formed beLv~ n cavity surface 39 and post surface 30, and extends along at least a portion of the length of cavity surface 39 such that supply ~nmllllc 50 is in fluid comm~n:c~tion with both supply chamber 32 and one or more contiguous vanes 48.
Vanes 48 are plel~l~bly defined by the juxta position of end surface 28 of insert post 26 and grooves 46 of insert 21. Each vane 48 has a res--ltir~ width W and height H which, in turn, defines a vane cross sectional area A in accordance with the equation:

A = W * H

Thus, the individual vane exit area EA of each vane exit 52 is the product of exit width EW of that vane and height H, while the individual vane inlet area L~ of each vane inlet 54 is similarly the product of height H and the inlet width IW. The cum~ tive vane inlet area for an aloll--~g nozzle made in accordance with this invention is, Il.e.t~olt" the s~mm~tion of the individua1 vane inlet areas IA while similarly the cum~ tive vane exit area for an alo~ lg nozzle is the s~mm~tion ofthe individual vane exit areas EA.
Pl-,fw-.,d vanes 48 will feature a contin~lol~sly inwardly decreasing width so that EW is generally less than IW while height H is generally con~la.ll over the length of each vane 48. Because height H is prefw~ly ~ ed generally consl~r.l over the radial length of vane 48, the ratio of the vane exit area EA to vane inlet area IA is generally equal to the ratio of the vane exit width EW to vane inlet width IW.
Consequently, both ratios preferably define the nall~Wing conrol.n~ion of each vane 48. This narrowing confollll~lion ~-e~lably provides a continuously acceleratingliquid flow within each vane 48 as the liquid traverses each vane 48 in a direction from supply challll,cr 32 toward swirl chall~L,el 42.

W O 97/13584 PCTrUS96/16427 Although it is preferable that the width (and similarly the cross sectional areaA if the vane height H is consl~l) of each vane 48 continuously decreases inwardly from cavity surface 39, it has been found that the spray characteristics of liquid dispensed from nozzles made according to this invention are generally il~e~ ;ve to the amount of decrease in the vane width W. Thus, it is believed generally that the ratio of the vane exit width EW to the vane inlet width IW, and likewise the ratio of vane exit area EA to the vane inlet area IA (if vane height is consl~), may vary in a range from about 0.10 to about 1.0 without generally deviating from the scope of this invention.
Not int~?n~in~ to be bound by any particular theory, it is believed that proper ~lim~ncioning of the cross sectional exit area EA of vanes 48 in cooperation with the proper sizing of cllamber diameter CD and orifice ~ metçr OD is critical to achieving the spray characteristics of the present invention. For example, it has been observed that as chamber ~ meter CD and individual and c~-m~ tive vane exit areas increase, the Sauter Mean Diameter (i.e., a quotient ~e~lesç~ g the average particle size of a spray) of a given spray generally decreases accolding to the following equation, and as graphically illustrated in FIG. 5:
SMD = 44.6 - 57.1 * (CD * EA) where SMD = Sauter Mean Diameter in microns.
CD = Chamber fli~m.o,t~r for values generally in a range of between about 0.5 mm and about 1.5 mm.
EA = Individual vane exit area for values generally in the range of between about 0.02 mm2 and about 0.07 mrn2.

Although FIG. 5 in~ic~tes a generally decreasing particle size as individual vane exit area EA and/or çh~mher di~ eler CD increase, data generally in-lic~t~c that the Sauter Mean DiallleLel of a resulting spray was found to generally increase if the individual vane exit area EA is about 0.12 mm2 and cl-alllber rli~meter CD is about 2.0 mm.
Based on the fore~,oi-lg relationships, it is believed that plerelled embo-lim~ntc of the present invention will have a c~-m~ tive vane exit area (i.e., a sllmm~ti~n of the individual vane exit areac EA) in a range of between about 0.18 mm2 and about 0.36 mm2 and generally a challll~er ~ meter CD in a range of between about 1.3 mm and about 2.0 mm, and most preferably the chamber ~
CD being in a range of between about 1.4 rmn and about 1.5 mm. It has been foundby the applicant that these ple~lled emborlimentc will generally produce a spray CA 02234446 l998-04-09 W O 97/13584 PCT~US96/16427 being in the range of between about 38 microns to about 43 microns with a liquidpressure being in the range of between about 160 psig to about 200 psig.
Nozzle body 20, feed tube 23, and nozzle insert 21 may be constructed from any subst~nti~lly rigid material, such as steel, ~lnmimlm or their alloys, fiberglass, or plastic. However, for economic reasons, each is most plc:re,~bly composed of polyethylene plastic and formed by injection moll1in~, although other processes such as plastic welding or adhesive connectiQn of app,~pliale parts are equally applicable.
In operation of a prere,l~d embodiment of the present invention, liquid product is provided from a container through feed tube 23 under pressure created by a m~nll~lly-~ctu~ted piston and cylinder arrangement, or other m~ml~lly actu~tedpump device. The fluid, upon exiting feed tube 23 enters supply chamber 32 whereupon it longitu-~inAlly traverses nozzle body 20 and enters supply annulus 50.
The pressurized liquid then passes through supply annulus 50 and is directed into the plurality of vanes 48. ~lthollgh it is prefe".,d that feed tube 23, supply ch~mhçr 32 and supply annulus 50 cooperate to transport the liquid from the corllainer to the plurality of vanes 48, it should be understood that other supply structures (e.g., ch~nn~olc, chambers, reservoirs etc.) may be equaUy suitable singly or in combination for this purpose. rler~,~bly, the liquid is continuously accelerated by the decreasing cross sectional area A of each vane 48 which directs the liquid radially inward toward swirl ch~"ber 42. The accelerated liquid plefe.~bly exits the vanes 48 generallytangentially into swirl chamber 42, and the rot~ti~-n~l energy imparted to the liquid by each vane 48 and the 1~-1g~ ;Al mo~.,."t;nl into swirl r~ h~ 42 generally creates a low pressure region adjacent the center of swirl .~ .,.h~l 42. This low pressureregion will tend to cause ambient air or gas to p~.,c;l,~e into the core of swirl chamber 42. The liquid then exits swirl çh~mb~r 42 as a thin liquid film (surrounding afol~ ;oned air core) and is directed through discharge orifice 44 to the a",bie"l en~,;.ol~n~ . Upon discha~e, inherent instabilities in the liquid film cause the liquid to break into lig~ment~ and then discrete particles or d,oplelst thus forming a spray.
As best illustrated in FIG. 6, a p~cr~ ;d embodiment of the present invention genelales a spray of liquid particles or dlu~'et~ having a mean particle size of about 40 microns at a fluid ples~.lle of around 160 psig when used to dispense a fluidhaving a viscosity of about 10 ce.,lipoise. For co~"pa~ison only, the best knownco,...~P~,ially available nozzle of which the appli~ l is aware which may be adapted for use in a manual~ u~ted pump di~pe~se~ generally produces a spray having a mean particle size of about 40 microns at a pressure about 200 psig or more for a liquid of such viscosily. The appro~ e 40 psig p~ ul~ red~lctiQn in that exampleto achieve generally a 40 micron mean particle size advantageously l~itnCl~tes into a CA 02234446 l998-04-09 W O 97/13584 PCT~US96/16427 lower input force to create the necçc~ry fluid pressure. Consequently, the user of a m~ml~lly-~ctll~ted pump type dispenser Co~ g an atomizing no_zle embodying the present invention would have to exert less force to achieve generally a 40 micron spray, and the device itself would presumably be easier and less expensive to m~mlf~cture due to the lower pressure requirements.
While the structure of the present invention is not intçnded to be limited to the dispensing of any specific product or category of products, it is recognized that the structure of the prerel,ed embodiments is particularly efficient and applicable for the dispensing, at pressures about 160 psig, of liquid products having a viscosity, density, and surface tension generally about 10 centipoise, 25 dynes per cPntimetP~
respectively. It will be understood by one skilled in the art, however, that deviation from these values for applopli~le di~rele.~l applications and/or for dispensing of various liquids and viscosities should be possible without af~ecting the spray characteristics of the present invention. For example, it is believed that the viscosity of the liquid to be ~ pP~n~e(l may vary from about 5 cps to 20 cps without deviating from the scope of this invention.
The fol~oi"g description of the pler~lled embo~imPnt~ of the invention has been presented for purposes of illustration and description. It is not inten-~ed to be PYh~lstive or to limit the invention to the precise form disclosed. Mo~ifi~tic)ns or variations are possible and conlelllpla~ed in light of the above te~chingc by those skilled in the art, and the embodiments ~icc~lcsed were chosen and desclil,ed in order to best illustrate the principles of the invention and its practical application, and indeed to thereby enable ~Itili7~tiQn of the invention in various embotlimPntc and with various moriific~tions as are suited to the particular use contemplated. It is intPn-lPd that the scope of the invention be defined by the claims appended hereto.

Claims (8)

What is claimed is:

1. An atomizing nozzle for dispensing a liquid from a container in the form of aspray of liquid particles, the atomizing nozzle including a supply structure fortransporting a liquid under pressure from a container, a discharge orifice in fluid communication and generally concentric with the swirl chamber, the atomizing nozzle characterized in that it further includes;

an orifice diameter of preferably 0.35 mm;
a plurality of generally radial vanes;

a swirl chamber in fluid communication with the plurality of vanes and having a chamber diameter;

the swirl chamber diameter preferably being in a range of between 1.3 mm and 2.0 mm, more preferably being in a range of between 1.4 mm and 1.5 mm; and the plurality of vanes generally decreasing in cross sectional area toward the swirl chamber and having a cumulative vane exit area being in a range of between0.18 mm2 and 0.36 mm2.

2. The atomizing nozzle according to claim 1, characterized in that it further includes three vanes, each vane having an individual vane exit area being in a range of between 0.06 mm2 and 0.12 mm2.

3. An atomizing nozzle for dispensing a liquid from a container, the atomizing nozzle including a discharge orifice being disposed generally concentric with the swirl chamber and in fluid communication therewith a substantially cup shaped nozzle insert having an insert surface and a cavity with an end face and a nozzle body for receiving and retaining the nozzle insert, the nozzle body having a supply chamber for receiving the liquid to be atomized under pressure from the container, and an insert post being disposed generally within the supply chamber and having an end surface, the atomizing nozzle characterized in that it further includes;

an orifice diameter of preferably 0.35 mm;

a plurality of generally radial grooves disposed on the end face;

a swirl chamber adjacent the end face having a chamber diameter and being disposed generally concentric with the cavity and in fluid communication with the grooves, the chamber diameter preferably being in a range of between 1.3 mm and 2.0 mm, more preferably being in a range of between 1.4 mm and 1.5 mm; and a plurality of generally radial vanes substantially defined by the end surface and the grooves, the plurality of vanes being in fluid communication with the supply chamber and generally decreasing in cross sectional area toward the swirl chamber and having a cumulative vane exit area being in a range of between 0.18 mm2 and 0.36 mm2.

4. The atomizing nozzle according to claim 3, characterized in that it further includes three vanes, each vane having an individual vane exit area being in a range of between 0.06 mm2 and 0.12 mm2.

5. A method of dispensing a liquid from a manually-actuated pump dispenser, characterized in that it includes the following steps:

providing an atomizing nozzle having, in successive fluid communication, a supply chamber, a plurality of generally radial vanes, a swirl chamber, and a discharge orifice;

providing a liquid having a viscosity being in range of between 5 cps to 20 cps from a container to the atomizing nozzle at a pressure below 200 psig by manually actuating a pump device;

directing the liquid into the plurality of generally radial vanes;
directing the liquid via the radial vanes into the swirl chamber;

creating an atomized spray by directing the liquid from the swirl chamber and through the discharge orifice such that the mean particle size of the liquid particles is in a range of between 38 microns to 43 microns.

6. The method according to claim 5, characterized in that the step of providing the atomizing nozzle further includes providing an atomizing nozzle having a cumulative vane exit area being in a range of between 0.18 mm2 and 0.36 mm2.

7. The method according to claim 5 or 6, characterized in that the step of providing the atomizing nozzle further includes providing an atomizing nozzle having a swirl chamber diameter being in a range of between 1.3 mm and 2.0 mm.

8. The method according to claim 5, 6 or 7, characterized in that the step of providing the atomizing nozzle further includes providing an atomizing nozzle having an orifice diameter of 0.35 mm.