Disclosed is a method of designing an aerosol spray dispensing system. One or more to-be-determined attributes of the spray dispenser system are identified, including properties of a fluid to be dispensed, characteristics of the dispensing mechanism, and performance characteristic values. The identified attributes are determined using equations taking into account relationships among the properties of the fluid to be dispensed, the characteristics of the dispensing mechanism and the performance characteristic values. Once determined, the attributes are used to design the spray dispensing system.

An aerosol dispenser assembly (1) has a container (2) holding a liquid product and a liquefied gas propellant for propelling the liquid product from the container, the propellant being present in a quantity of at most about 25% by weight of the contents of the container (2). A valve (4) is attached to the container (2) for selectively dispensing the liquid product from the container (2) as a mist. The assembly (1) is configured such that the mist has a small particle size, is dispensed at an expeditious rate, and very little product is retained in the container (2) when the propellant is depleted.

An aerosol dispenser assembly (1) having a container (2) that contains a liquid product, and a propellant for propelling the liquid product from the container (2). The propellant is a dual phase hydrocarbon propellant, is free of normal butane, and is at most 25% by weight of the contents of the container. A valve (4) is attached to the container (2) for selectively dispensing the liquid product from the container (2) as a mist, the mist having an average particle size of less than 35 .mu.m (0.0014"), over at least 75% of the life of the dispenser assembly (1). The dispenser assembly (1) is capable of dispensing over 98% by weight of the liquid product from the container (2). A vapor tap (24) is formed in the valve (4) to facilitate thorough mixing of the propellant and the liquid product prior to dispensing, and a valve stem (12) is disposed in the valve (4). The valve stem (12) defines at least one stem orifice (26) for flow of the product during dispensing. The vapor tap (24) has a diameter of about 0.013" (0.330 mm) to about 0.019" (0.483 mm). A dispenser cap (16) is mounted on the valve stem (12) for actuating the valve (4) to dispense the liquid product. The dispenser cap (16) defines an exit path (28), through which the liquid product can be dispensed. A breakup bar (30) is positioned in the exit path (28) of the dispenser cap (16) to break up the liquid product in order to reduce the size of the particles before the liquid product is dispensed.

An environmentally friendly insect eradication method and apparatus for removing invasive insects from tunnels bored through and within trees and other similarly composed structures by providing a canister containing a pressurized, non-flammable, non-ozone depleting fluorocarbon propellent disposed therein with the propellent having a pre-use internal pressure in the approximate range of about 75 psig to 150 psig and where the pressure is sufficient to introduce some or all of the propellent into the internal portion of an insect tunnel bored in an invaded structure. A gas introduction nozzle is inserted into an entrance or exiting insect bore in such a manner so as to cause a valve mechanism, in operative communication with the nozzle and cannister to be displaced and allow the propellent to exit the canister and enter the internal portion of the invaded insect bore to displace or otherwise eradicate the insect.