04829641 is referenced by 84 patents and cites 9 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
7/64959
Publication Number
4829641
Application Date
June 22, 1987
Publication Date
May 16, 1989
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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