Pressure change indicator

Claim 2

A closure device for a hermetically sealable container, said closure device comprising: a flexible panel constructed and arranged to move inwardly and outwardly with respect to the interior of the container in response to changes in pressure within the container and to assume a relatively outward position in response to at least atmospheric pressure inside the container and to assume a relatively inward position when the pressure inside the container is relatively lower, and a color concealing and revealing member exterior to said container having a portion of a major surface thereof attached to said flexible panel, said major surface being sufficiently conformed to the shape of said flexible panel to conceal at least that portion of the flexible panel underlying the outer periphery of said major surface when the flexible panel is in the relatively inward position but not sufficiently conformed To the shape of the flexible panel to conceal said portion of the flexible panel when the flexible panel is in the relatively outward position, thereby revealing a contrasting color visible on said portion of the flexible panel only when the flexible panel is in the outward position.

Claim 3

A closure according to claim 1 wherein the contrasting color visible on said portion of the flexible panel is provided by a colored coating on said portion.

Claim 4

A closure according to claim 1 wherein said color is provided by a color on said major surface of said color revealing and concealing member, said color becoming visible when the flexible panel is in said relatively outward position by means of a reflection from the said flexible panel.

Claim 5

A closure according to claim 3 wherein said portion of said flexible panel is capable of reflecting at least 50 percent of the visible light falling upon it.

Claim 6

A closure according to claim 3 wherein said portion of said flexible panel is capable of reflecting at least 65 percent of the visible light falling upon it.

Claim 7

A closure according to claim 1 wherein said color concealing and revealing member is attached to said flexible panel with an adhesive.

Claim 8

A closure according to claim 3 wherein said color concealing and revealing member is attached to said flexible panel with an adhesive.

Claim 9

A closure according to claim 7 wherein said adhesive is heat-activatible and is contained in a pigmented coating on said major surface of said color revealing and concealing member.

Claim 10

A closure according to claim 1 wherein said color visible on said portion of the flexible panel results from an irreversible heat-activated color change.

Claim 11

A closure for a hermetically sealed container, said closure being adapted to provide at least a visual indication of pressure changes within said container, said closure comprising: a top panel and an integral peripheral skirt with means on said skirt for engaging said container and holding the undersurface of said closure in sealed relation over the mouth of said container, said top panel comprising a peripheral portion which is in the plane of the top of the closure and a movable center portion capable of flexing in response to changes in pressure, said movable center portion being constructed and arranged to assume a position above the plane of the top of the closure when the pressure inside the container is at least atmospheric and to assume a position below the plane of the top of the closure when said pressure is subatmospheric, at least the movable center portion of said top panel being capable of reflecting at least 50 percent of the light falling upon it, and a button-like member having a colored undersurface, the color of said colored undersurface contrasting with the color of said movable center portion, a portion of said colored undersurface being attached to the upper surface of said movable center portion, the area of said colored undersurface being substantially coextensive with the area of said movable center portion, the shape of said colored undersurface being substantially conformed to the shape of said movable center portion only when said movable center portion is below the plane of the top of the closure, whereby the color of said colored undersurface becomes visible by reflection from said movable center portion when said movable center portion is above the plane of the top of the closure but is concealed when the movable center portion is below said plane.

Claim 12

A closure for a hermetically sealed container, said closure being adapted to provide at least a visual indication of pressure changes within said container, said closure comprising: a top panel and an integral peripheral skirt with means on said skirt for engaging said container and holding the undersurface of said closure in sealed relation over the mouth of said container, said top panel comprising a peripheral portion which is in the plane of the top of the closure and a movable center portion capable of flexing in response to changes in pressure, said movable center portion being constructed and arranged to assume a position above the plane of the top of the closure when the pressure inside the container is at least atmospheric and to assume a position below the plane of the top of the closure when said pressure is subatmospheric, at least the movable center portion of said top panel being capable of reflecting at least 50 percent of the light falling upon it, and a button-like member having a colored undersurface, the color of said colored undersurface contrasting with the color of said movable center portion, a portion of said colored undersurface being attached to the upper surface of said movable center portion, the area of said colored undersurface being substantially coextensive with the area of said movable center portion, the shape of said colored undersurface being substantially conformed to the shape of said movable center portion only when said movable center portion is below the plane of the top of the closure, whereby the color of said colored undersurface becomes visible by reflection from said movable center portion when said movable center portion is above the plane of the top of the closure but is concealed when the movable center portion is below said plane.

Claim 13

A hermetically sealed container comprising: a flexible panel constructed and arranged to move inwardly and outwardly with respect to the interior of the container in response to changes in pressure within the container and to assume a relatively outward position in response to at least atmospheric pressure inside the container and to assume a relatively inward position when the pressure inside the container is relatively lower, and a color concealing and revealing member exterior tO said container having a portion of a major surface thereof attached to said flexible panel, said major surface being sufficiently conformed to the shape of said flexible panel to conceal at least that portion of the flexible panel underlying the outer periphery of said major surface when the flexible panel is in the relatively inward position but not sufficiently conformed to the shape of the flexible panel to conceal said portion of the flexible panel when the flexible panel is in the relatively outward position, thereby revealing a contrasting color visible on said portion of the flexible panel only when the flexible panel is in the outward position.

Claim 14

A hermetically sealed container comprising: a flexible panel constructed and arranged to move inwardly and outwardly with respect to the interior of the container in response to changes in pressure within the container and to assume a relatively outward position in response to at least atmospheric pressure inside the container and to assume a relatively inward position when the pressure inside the container is relatively lower, and a color concealing and revealing member exterior tO said container having a portion of a major surface thereof attached to said flexible panel, said major surface being sufficiently conformed to the shape of said flexible panel to conceal at least that portion of the flexible panel underlying the outer periphery of said major surface when the flexible panel is in the relatively inward position but not sufficiently conformed to the shape of the flexible panel to conceal said portion of the flexible panel when the flexible panel is in the relatively outward position, thereby revealing a contrasting color visible on said portion of the flexible panel only when the flexible panel is in the outward position.