Viscous product dispensing squeeze bottle having a self-venting automatic shut-off valve

Claim 1

A viscous product dispensing package comprising a squeeze bottle made of elastic material and containing the viscous product, said bottle having a mouth provided with a dispensing valve that is elastically biased normally closed and opened by the pressure of said product when the product is displaced to the valve by squeezing and at least partially collapsing the bottle so as to dispense at least a portion of the product through the valve, elastic return of the bottle to its uncollapsed condition after said squeezing requiring the venting of air into the bottle to replace said portion of the product, said valve having at least one permanently open passage extending from the outside of the bottle to its inside and having a flow area related to the viscosities of air and said product so as to permit air to be sucked therethrough to permit said elastic return to the bottle and block gravitational flow of said product through the passage, said valve having a rigidly positioned rigid valve head having a periphery, and an elastically flexible diaphragm having a central opening with a periphery normally pressed on said periphery of the valve head by the elasticity of the diaphragm when the valve is in its normally closed condition, said passage being formed through said rigid valve head and the valve head having an outside exposed substantially directly to the ambient air outside of said valve.