WO2011077114A1

WO2011077114A1 - Hand-held trigger sprayer

Info

Publication number: WO2011077114A1
Application number: PCT/GB2010/052083
Authority: WO
Inventors: Maud Portier; Chris Witty
Original assignee: Reckitt & Colman (Overseas) Limited
Priority date: 2009-12-24
Filing date: 2010-12-14
Publication date: 2011-06-30
Also published as: GB0922529D0

Abstract

A trigger sprayer (20) for a manually operated hand-held spraying device is described, the trigger sprayer comprises; a housing (23) having a cylinder (21) therein: a liquid inlet in communication with the cylinder; an outlet conduit in communication at one end with the cylinder and in communication at its other end with a nozzle wherein the nozzle is provided with an outlet orifice; a piston being received in the cylinder; the housing having a trigger (22) operatively coupled thereto; the trigger being operatively coupled to the piston: a precompression valve in a fluid path between the piston and the outlet orifice; the precompression valve being operable, in use, to allow liquid in a first part of the fluid path to reach the outlet orifice only after a predetermined pressure is established in the cylinder and being operable further to stop liquid from reaching the outlet orifice when the pressure in the cylinder falls below said predetermined pressure; a biasing means operable to bias the piston away from the cylinder; the precompression valve element is configured to require an activation force of >40N to be applied by a user to the trigger to achieve said predetermined pressure.

Description

Hand-Held Trigger Spraver

Field of the Invention

The present invention is related to the field of manually operated hand-held trigger sprayers with a precompression valve and particularly, but not exclusively, trigger sprayers in combination with bottles of liquid wherein the liquid is an air freshening or air fragrancing composition.

Background

Increasingly there are environmental concerns relating to the use of aerosol products to deliver fine particles of liquid, in particular concerns relate to aerosols having chlorof!uorocarbon (CFC) propeilants, although now largely discontinued and volatile organic compound (VOC) propellants generally, such propellents may aggravate low altitude pollution problems, also they pose safety issues relating to their flammable nature. One trend away from such aerosol products is to use aerosols with compressed gas propellants and, although they cause less envBOnmental concerns, they suffer from numerous performance-related drawbacks such as large particle size and impaired particle throw. Another trend away from traditional aerosol products is toward manually-operated pump-type mechanisms to force fluid through a nozzle to atomise the liquid to be sprayed.

The field of the invention relates to manually operated trigger sprayers comprising a

precompression pump mechanism. The precompression pump mechanism Is present to prevent liquid from being expelled from an outlet orifice In a nozzle of a trigger sprayer until a predetermined pressure of the liquid is reached at which point a valve is forced open to permit liquid to be sprayed from the nozzle; the spray of liquid being arrested, stopped or cut off when the pressure of the liquid being pumped by the trigger sprayer in the pumping cylinder falls below a predetermined pressure. The pre-compression pump mechanism ensures that the product will only be delivered when sufficient pressure is available for atomization of the liquid regardless of the speed or force with which the pump mechanism is activated,

A drawback of known precompression trigger sprayers is that they only offer application in localised spraying tasks and/or for spraying liquids with a large particle size; neither of these spraying qualities are useful for tasks such as air freshening or the like where large volumes of space need to be filled such as when freshening and/or fragrancing a room with small particles of air freshening composition or air fragrancing composition and/or the like. It is an aim of the present invention to address these drawbacks with known sprayers and other associated drawbacks. Summary of Inventipn

According to a first aspect of the present invention there is provided therefore a trigger sprayer for a manually operated hand-held spraying device, the trigger sprayer comprising:

a housing having a cylinder therein;

a liquid inlet in communication with the cylinder;

an outlet conduit in communication at one end with the cylinder and in communication at its other end with a nozzle wherein the nozzle is provided with an outlet orifice;

a piston being received in the cylinder;

the housing having a trigger operative!y coupled thereto;

the trigger being opera tively coupled to the piston;

a precompression valve in a fluid path between the piston and the outlet orifice;

the precompression valve being operable, in use, to allow liquid in a first part of the fluid patfi to reach the outlet orifice only after a predetermined pressure is established in the cylinder and being operable further to stop liquid front reaching the outlet orifice when the pressure In the cylinder falls below said predetermined pressure;

a biasing means operable to bias the piston away from the cylinder;

characterised in that the precompression valve element is configured to require an activation force of ≥40N to be applied by a user to the trigger to achieve said predetermined pressure.

In the context of the present invention the term "hand-held" is understood to mean that a user could hold, support and operate the trigger sprayer according to the present invention in a single hand. Further, "operatively coupled" is understood to mean that the coupling between the components can be direct, indirect or the components can be integral with each other, wherein said coupling enables at least some reciprocal movement of one of said components when the other of said components is moved. Additionally, "activation force applied by the user to the trigger" is understood to mean that the force is applied by at least one of a user's fingers at or substantially adjacent to the end of the trigger remote from the piston to which it is operatively coupled such that the user operates the trigger to impart maximum leverage from the action of the trigger.

The precompression valve preferably comprises a spring valve element, the spring in said spring valve element may be a torsion spring, such as a coil or helical compression spring, which is shortened under application of the activation force permitting liquid in the cylinder to pass from the cylinder into the outlet conduit toward the outlet orifice, wherein the activation force is applied by a user imparting at least≥40N of force on the trigger to increase the pressure of the liquid in the cylinder. Typically the spring valve element provided in known commercially available trigger sprayers would be specified to require that tfie predetermined pressure can be achieved by no more than approximately 30N of activation force being applied by a user to the trigger. It is understood that the basis for the maximum value of 30N activation force was derived from consumer testing of trigger sprayers which illustrated that greater activation forces would be unacceptable from a consumer perspective as they would require too much exertion from tie user such that an unacceptably high number of users would consider the trigger sprayer mechanism to be either broken or faulty.

Despite prejudice within the field of trigger sprayers regarding the feasibility of trigger sprayers requiring activation forces of greater than 30N, the present invention has surprisingly found that by configuring the precompression valve element to require a larger predetermined pressure than commercially available trigger sprayers improved consumer benefits can be provided including such benefits as improved mechanical break up of the sprayed liquid into particles., improved throw which are discussed below along with other hitherto unrealised benefits. in one arrangement, the spring valve element may be specified to require that the predetermined pressure needed to be applied thereto to permit liquid in the first part of the fluid path to reach the outlet orifice is achieved by≥40N of activation force being applied by a user to the trigger. Preferably the spring valve element is specified to require that the predetermined pressure needed to be applied thereto to permit liquid in the first part of the fluid path to reach the outlet orifice is achieved by≥42.5N of activation force being applied by a user to the trigger. More preferably the spring valve element is specified to require that the predetermined pressure needed to be applied thereto to permit liquid in the first part of the fluid path to reach the outlet orifice is achieved by ¾45N of activation force being applied by a user to the trigger. Even more preferably the spring valve element is specified to require that the predetermined pressure needed to be applied thereto to permit liquid in the first part of the fluid path to reach the outlet orifice is achieved by≥47.5N of activation force being applied by a user to the trigger. Most preferably the spring valve element is specified to require that the predetermined pressure needed to be applied thereto to permit liquid in the first part of the fluid path to reach the outlet orifice is achieved by≥50N of activation force being applied by a user to the trigger. Ideally the spring valve element is specified to require that the predetermined pressure needed to be applied thereto to permit liquid in the first part of the fluid path to reach the outiet orifice is achieved by≥ 52.5N of activation force being applied by a user to the trigger.

Typically the trigger component of a conventional trigger sprayer comprises a housing and a pivoting trigger having a trigger-to-plvot length of ≤50mm; the trigger-to-pivot length being the distance between the end of the trigger and a pivot point on the housing, in contrast however, a trigger sprayer according to the present invention is preferably provided with a trigger-to-pivot length of ≥5mm, and more preferably provided with a trigger-to-pivot length of 350mm, and even more preferably provided with a trigger-to-pivot length of ≥70mm , and most preferably provided with a trigger-to-pivot length of ≥75mm, and ideally provided with a trigger-to-pivot length≥80mm,

Preferably the ratio of trigger length to the piston cycle length (ie- the greatest distance the piston is capable of moving in one linear direction) is at least 6:1 , more preferably the ratio of trigger length to the piston cycle length is at least 7:1 , even more preferably the ratio of trigger length to piston cycle length is at least 8:1 , and most preferably the ratio of trigger length to piston cycle length is at least 9:1.

The trigger sprayer according to the present invention may have the nozzle and outlet orifice tuned to assist with the mechanical break-up of the liquid being sprayed such that the average particle size of the resultant sprayed particles is <100μm, preferably the average particle size of the resultant sprayed particfes is≤90,um, even more preferably the average particle size of the resultant sprayed particles is <80>m, most preferably the average particle size of the resultant sprayed particles is≤70μm , ideally the average particle size of the resultant sprayed particles is ≤60 μm.

The trigger sprayer according to the present Invention may be configured such that, in use, It is capable of spraying a liquid with a viscosity similar to water, and preferably substantially similar to water, with a throw of >50cm; the "throw" being the distance the liquid is sprayed away from the nozzle. Preferably the sprayer may be configured such that, in use, it is capable of spraying such a liquid with a throw of >100cm. More preferably the sprayer may be configured such that, in use, it is capable of spraying such a liquid with a throw of >150cm, Even more preferably the sprayer may be configured such that, in use, it is capable of spraying such a liquid with a throw of >200cm. Most preferably the sprayer may be configured such that, in use, it is capable of spraying such a liquid with a throw of >250cm. Ideally the sprayer may be configured such that, In use, it is capable of spraying such a liquid with a throw of >300cm.

The nozzle may be provided with at least one swirl chamber to impart additional re!ative velocity to the liquid to be sprayer prior to exiting the outlet orifice of the sprayer

Preferably liquid inlet, the cylinder and at feast a part of the outlet conduit is co-axial. Preferably the movement of the piston into and out of the cylinder is substantially co-axial with the liquid inlet and said at least a part of the outfet conduit. The outlet conduit is preferably L-shaped such that the ends thereof are substantially perpendicular with respect to each other +/- 30°, and preferably +/- 15° to permit a user to easily hold the trigger in one hand and target the direction they wish spray the liquid.

The housing may be configured to be connectable to a liquid container at one end of the housing and a non-movable arm to extend towards a rear side of the housing, and preferably the non- movable arm extends upwardly and rearwards toward the rear side of the housing. At the end of the non-movable arm remote from the housing the trigger may be pivotably connected thereto. The trigger is preferably arranged to extend from the pivot connection with the non-movable part of the housing to extend over the centre of the housing toward a front side of the housing. The trigger may be provided with an aperture in a part thereof that is substantially facing the front side of the housing, this aperture may permit the outlet orifice to pass therethrough to be connected to the nozzle at a foremost side of the trigger. This configuration of the housing is considered to be particularly advantageous at it permits improved leverage to be imparted by a user when operating the trigger to apply the required activation force: advantageously this improvement will not affect the ease of distribution of the trigger due to excessive increase of the footprint of the trigger which affects the ease of transport and on-sheif stacking when connected to a container of liquid.

The trigger may be a separate component that pivotally connects to the non-movable part of the housing, however, the trigger may be integral with the non-movable part of the housing but formed to permit the trigger to pivot toward or at the extremity of the non-rnovabie part.

Preferably the trigger may be directly coupled to the outlet orifice which is engaged directly with the piston or engaged directly with a rod connected to the piston. The trigger is preferabiy coupled to outlet conduit at the substantially perpendicular angle between the two ends of the conduit, in this preferred arrangement the movement of the trigger can be arranged to provide a substantially linear force co-axial with the movement of the piston in order to conserve the energy imparted by a user on the trigger and also prevent needless excess stress to be imparted to the outlet conduit and potentially promoting it to fail.

The housing may be integrally formed but can, alternatively, be made of component parts.

The biasing means is preferably a spring which may be a torsion spring, such as a coil or helical compression spring, which is shortened under application of the activation force causing movement of the piston toward and further in to the cylinder, the biasing means being operable to return the piston and in turn the trigger toward their starting positions.

According to a second aspect of the present invention there is provided therefore a trigger sprayer for a manually operated hand-held spraying device comprising:

a housing having a cylinder therein;

a liquid inlet in communication with the cylinder;

a piston being received in the cylinder;

the housing having a trigger operatively coupled thereto;

the trigger being operative coupled to the piston;

the precompression valve being operable, in use, to allow liquid in a first part of the fluid path to reach the outlet orifice only after a predetermined pressure is established in the cylinder and being operable further to stop liquid from reaching the outlet orifice when the pressure in the cylinder falls below said predetermined pressure;

a biasing means operable to bias the piston away from the cylinder;

characterised in that the precompression valve is configured to resist rupture to liquid pressures in the cylinder of ≤350,0Ό0 N/m²

Typically the precompression valve provided in a commercially available trigger sprayer is specified to require that a rupture pressure of <200,000 N/m²be present before permitting liquid to pass therethrough into the outlet conduit. In contrast however, the precompression valve provided in a trigger sprayer according to the present invention is specified to resist rupture to liquid pressures below 350,000 N/m² Preferably, the precompression valve provided in a trigger sprayer according to the present invention is specified to resist rupture to liquid pressures below 400,000 N/m², More preferably, the precompression valve provided in a trigger sprayer according to the present Invention is specified to resist rupture to liquid pressures below 450,000 N/m², Even more preferably, the precompression valve provided in a trigger sprayer according to the present invention is specified to resist rupture to liquid pressures below 500,000 N/m². Most preferably, the precompression valve provided in a trigger sprayer according to the present invention is specified to resist rupture to fiquid pressures below 550,000 N/m² Ideally, the precompression valve provided in a trigger sprayer according to the present invention is specified to resist rupture to liquid pressures below 600,000 N/m². According to a third aspect of the present invention there is provided therefore a manually operated hand-held spraying device comprising a trigger sprayer according to the first or second aspect connected to a container comprising a reservoir of liquid.

According to a fourth aspect of the present invention there is provided therefore an air freshening device wherein said device comprises manually operated hand-held spraying device comprising a trigger sprayer according to the first or second aspect connected to a container comprising a reservoir of an air freshening composition.

According to a fifth aspect of the present invention there is provided therefore an air freshening device wherein said device comprises manually operated hand-held spraying device comprising a trigger sprayer according to the first or second aspect connected to a container comprising a reservoir of an aqueous air freshening composition wherein said composition comprises:

85-95%wt water;

≤1 %wt malodour counteractant;

1-10%wt alcohol;

1-5%wt surfactant;

0.01 -5%wt fragrance;

≤%wt adjuvents; wherein %wt is of (lie composition as a whole and adds up to exactly 100%wt.

Any of the features described herein may be combined with any of the above aspects in any combination.

Description of an Embodiment

Embodiments of the invention will now be described, by way of example only, with reference to the following drawings in which;

Fig.1 shows a prior art pre-compression trigger sprayer;

Fig.2 shows a prior art pre-compression trigger sprayer in section;

Fig.3 shows side elevation of a trigger sprayer according to the present invention with a partial cutaway section; and

Fig.4 shows a perspective view of a trigger sprayer according to the present invention connected to a liquid container.

Figs. 1 &2 illustrate a prior art pre-compression trigger sprayer 1 comprising a pre-compression type pump mechanism 2 connected via a liquid inlet 3 to a diptube 4 which extends downwardly into a container of liquid 5 (shown in cutaway section). The pre-compression pump mechanism 2 is connected to an outlet conduit 6 which terminates at a nozzle 7. A trigger 8 is a!so provided, the trigger being operatively coupled to the pump mechanism 2. The trigger is pivotally mounted to a housing 9 which is shown in dotted lines.

There are a wide variety of pre-compression type pump mechanisms which may be suitable for use in the present invention, the particular trigger-type version illustrated in Figs. 1&2 is illustrative of the operating features typical of such pump mechanisms. A more detailed description of the features and components of this pump assembly may be found in EP0449046, this patent application being incorporated herein by reference. Pump assemblies of this general type are commercially available from Guala Dispensing S.p.A..

To provide clarity on the operation of the prior art pre-compression sprayers their mode of operation will be described with reference to Figs. 1&2. To begin a cycle the trigger θ is moved by a user about its pivot point 10 by user imparted finger pressure, this movement is converted into downward movement of the piston 11 and precompression valve 12 to increase the liquid pressure within a cylinder 13 of the pump 2. The pressurised liquid acts upon the precompression valve 12, causing it to open to the outlet conduit 6 once the predetermined pressure of for that valve 12 is reached. The predetermined pressure for the precompression valve can be controlled by the force which must be imparted on a pre-compression spring 14 to cause it to contract and permit movement of the valve 12 relative to the piston 11 , Thereafter the pressurised liquid travels through the outlet conduit 6 to the nozzle 7. Once the piston 11 reaches the end of its cycle length (or the trigger is released during an incomplete cycle), and pressure within the cylinder 13 diminishes to the point where the precompression valve 12 is no longer open, accordingly the valve 12 closes and liquid no longer flows to or out of the nozzle 7. Once the user releases the trigger 8 a spring 15 returns the piston 11 toward its original position and since the piston is operatively coupled to the trigger 8 reciprocal movement of the trigger 8 allows it to pivot about the pivot point 10 and return to its original position read for the next pumping cycle. This upward movement of the piston 11 imparts negative pressure within the cylinder 13 which causes a ball valve to become unseated and permit liquid to pass up the diptube 4 into tie cylinder 13, the ball valve 16 being re-seated once the pressure in the cylinder is equalised with the pressure in the container.

A pre-compression pump mechanism ensures that a liquid is only sprayed when sufficient liquid pressure is available for atomisation. The pre-compression spring 14 is tensioned to effectively block liquid flow from the cylinder 13 past the valve 12 during the perbd of initial pressure rise and during the rapid decrease of pressure at the end of the pumping cycle. Regardless of the speed or authority with which tie trigger is actuated and the piston 11 moved deeper into the cylinder 13, liquid pressure within the cylinder 13 will accumulate without liquid being discharged until the predetermined threshold pressure is reached. When the liquid pressure in the cylinder 13 begins to fall at the end of a pump stroke, the valve 12 closes as the pressure falls below this predetermined threshold pressure. This system may eliminate the emission of droplets having and unsatisfactorily large particle size and, importantly, eliminate streaming or dribble of the liquid at the end of the delivery stroke.

Turning to Figs. 3&4 a trigger pump 20 in accordance with the present invention can be seen. Fundamentally the operation thereof is analogous to a known pre-compression sprayer however a sprayer 20 according to the present invention has a series of important distinctions thereover. In order to provide the characteristics required the pre-compression spring (not shown) of a greater spring strength than hitherto used in a commercially available trigger sprayer. This increase in the spring strength permits a greater liquid pressure to be achieved in the cylinder 21 when a user activates the trigger 22 before the pre-compression valve (not shown) is permitted to let liquid pass into the liquid outlet conduit (not shown). Of course the increase in the spring strength of the pre-compression spring increases the activation force a user must impart to the trigger in order to operate the sprayer 20. Typically commercially available trigger sprayers require approximately 30 N of activation force to be applied by a user to the trigger in order to operate the trigger through an operation cycle, However, the pre-compression spring sprayer 20 is configured to require that the user must input an activation force of≥40N, but the acbvation force needed to be imparted to sprayer 20 could be as high as ¾50N or more. If a convention trigger sprayer 1 such as those described in Figs.1 &2 required such high activation forces it would simply not be possible for a vast majority of users to comfortably actuate the sprayer as they could not the required activation force through the trigger 8.

The trigger 20 has a housing 23 has an internal thread to engage with a liquid container 24 via a standard arrangement and has a top surface 25 from which extends a central conduit cover 26 and a non-movab!e arm 27, the arm 27 extend upwardly and rearwardly from the top surface 25, At the end of the non-movable arm 27 is a pivot point 28 to which the trigger 22 is plvotably connected. The trigger 22 is formed to extend from the pivot 28 over the centre of the housing toward a front side of the housing 23, The trigger has an aperture 29 in its front facing side to permit a liquid outlet orifice 30 to pass therethrough, the liquid outlet orifice being connected to a nozzle 31 at the foremost side of the trigger. The aperture 29 is sized to prevent the trigger 22 impinging on the outlet orifice 30 when the trigger is actuated and moved toward the housing 23.

The trigger sprayer shown in Figs.1&2 has a trigger-to -pivot length of approx. 50mm; wherein the trigger-to-pivot length is the distance between the end of the trigger and a pivot point on the housing. In contrast however, the trigger sprayer 20 in Figs.3&4 has a trigger-to-pivot length of 81mm. The trigger 22 is particularly advantageous over hitherto known triggers at it permits a user improved leverage to be imparled when operating the trigger 22 and, in turn, permits the user to achieve the required activation force when using a single hand to operate the sprayer 20.

A further advantage of the sprayer 20 is that by having the trigger 22 extend from the back side of the sprayer 20 to the front side thereof, a major proportion of the trigger is hidden within the footprint of the liquid container 24 and this ensures that the trigger sprayer 20 is commercially viable as the increased trigger length does not affect the ease of distribution including the ease of transport and ease of on-shelf stacking. Furthermore, the non-movable arm 27 advantageously is capable of sitting in the heel of a user^'s hand, the heel being the part of a human hand between the thumb and forefinger, to assist in preventing hand fatigue whilst operating the sprayer 20 as the heel supports a portion of the weight of the sprayer 20.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A trigger sprayer for a manually operated hand-held spraying device, trie trigger sprayer comprising:

a housing having a cylinder therein;

a liquid inlet in communication with the cylinder;

an outlet conduit in communication at one end with the cylinder and in communication at its other end with a nozzle wherein the nozzle is provided with an outJet orifice;

a piston being received in the cylinder;

the housing having a trigger operatively coupled thereto;

the trigger being operatively coupled to the piston;

a biasing means operable to bias the piston away from the cylinder;

2. A trigger sprayer according to claim 1 , wherein the precompression valve comprises a spring valve element.

3. A trigger sprayer according to claim 1 or claim 2, wherein the spring valve element is specified to require an activation force of ≥42.5N to be applied by a user to the trigger, and preferably≥45N, and more preferably≥47.5N, and even more preferably≥50N, and ideally≥ 52.5N.

4. A trigger sprayer according to any preceding claim , wherein the trigger is provided with a trigger-to-pivot length of 555mm , and preferably provided with a trigger-to-pivot length of 260mm, and more preferably provided with a trigger-to-pivot length of 570mm, and most preferably provided with a trigger-to-pivot length of 275mm , and ideally provided with a trigger-to-pivot length 280mm.

5. A trigger sprayer according to any preceding claim, wherein the ratio of trigger length to the piston cycle length is at least 6:1 , and preferably the ratio of trigger length to the piston cycle length is at least 7:1 , more preferably the ratio of trigger length to piston cycle length is at least 8:1 , and most preferably the ratio of trigger length to piston cycle length is at least 9:1.

6. A trigger sprayer according to any preceding claim, wherein the average particle size of the sprayed liquid particles is≤100μιη, and preferably is <9<なL/m, and more preferably is <80//m, and most preferably is≤70pm, and ideally is≤60μm .

7. A trigger sprayer according to any preceding claim , wherein the trigger sprayer is configured such that, in use, it is capable of spraying a liquid with a viscosity similar to water with a throw of >50cm; and preferably >10Gcm; and more preferably >150cm; and even more preferably >200cm; and most preferably >250cm; and ideally >300cm.

8. A trigger sprayer according to any preceding claim, wherein the outlet conduit is L- shaped such that tie ends thereof are substantially perpendicular with respect to each other +/- 30°, and preferably +/- 15°.

9. A trigger sprayer according to any preceding claim, wherein the housing is configured to be connectable to a liquid container at one end of the housing and has a non-movable arm that extends towards a rear side of the housing which is pivotally connected to the trigger at the end thereof such that the trigger is arranged to extend from the pivotal connection to extend over the centre of the housing toward a front side of the housing.

10. A trigger sprayer according to claim 10, wherein the trigger is provided with an aperture in a part thereof that is substantially facing the front side of the housing to permit the outlet orifice to pass therethrough to be connected to the nozzle at a foremost side of the trigger.

11. A trigger sprayer for a manually operated hand-held spraying device, the trigger sprayer comprising:

a housing having a cylinder therein;

a liquid inlet in communication with the cylinder;

a piston being received in the cylinder;

the housing having a trigger operatively coupled thereto;

the trigger being operative coupled to the piston:

the precompression valve being operable, in use, to allow liquid in a first part of the fluid path to reach the outlet orifice only after a predetermined pressure is established in the cylinder and being operable further to stop liquid from reaching the outlet orifice when the pressure in the cylinder falls below said predetermined pressure:

a biasing means operable to bias the piston away from the cylinder;

characterised in that the precompression valve is configured to resist rupture to liquid pressures in the cylinder of ≤350,000 N/m²

12. A trigger sprayer according to claim 11 , wherein the precompression valve is specified to resist rupture to liquid pressures below 400,000 N/m², and preferably to liquid pressures below 450,000 N/m², and more preferably to liquid pressures below 500,000 N/m*, and most preferably to liquid pressures below 550,000 N/m², and ideally to liquid pressures below 600,000 N/m².

13. A manually operated hand-held spraying device comprising a trigger sprayer according to any preceding claim wherein the sprayer is connected to a container comprising a reservoir of liquid.

14. An air freshening device wherein said device comprises manually operated handheld spraying device comprising a trigger sprayer according to any of claims 1-12 wherein the device is connected to a container comprising a reservoir of an air freshening composition.

15. An air freshening device wherein said device comprises manually operated hand-held spraying device comprising a trigger sprayer according to any of claims 1-12 wherein the device is connected to a container comprising a reservoir of an aqueous air freshening composition wherein said composition comprises:

85-95%wt water;

≤l %wt malodour counteractant;

1 -10%wt alcohol;

1 -5%wt surfactant;

0.01 -5%wt fragrance:

≤2%wt adju vents; wherein %wt is of the composition as a whole and adds up to exactly 100%wt.

16. A trigger sprayer substantially as described herein with reference to the drawings of Figs. 2&3.