04907321 is referenced by 69 patents and cites 25 patents.

An interlocking closure device including two closure elements arranged to be interlocked over a predetermined length, each of said closure elements having different colors for establishing visually the completeness of the occlusion of the closure elements by providing color different from the closure elements when said closure elements are occluded, wherein the improvement comprises the introduction of a color change enhancement member in the internal channel of a translucent closure element whereby the closing and opening of the closure device is more easily detected by visual inspection.

Title
Enhanced color change interlocking closure strip
Application Number
64959
Publication Number
4907321
Application Date
January 31, 1989
Publication Date
March 13, 1990
Inventor
John W Williams
Oak Lawn
IL, US
Agent
Gary L Wamer
Assignee
First Brands Corporation
CT, US
IPC
B65D 77/10
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