EP0123557A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Flexible ferromagnetic marker for the detection of objects having markers secured thereto
Assignee: 3M Co
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Filing: 1984-04-25
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Granted: —
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Expires: 2004-04-25
Abstract
Abstract A marker adapted to be used with cloth or fabric articles to enable the detection thereof in an electromagnet article surveillance system within which the marker generates a detectable signal related to an alternating electromagnetic field applied within an interrogation zone, wherein the marker comprises an elongated strip of amorphous ferromagnetic ribbon sealed on all major surfaces within flexible polymeric cover layers having a low rate of water vapor transmission, and a high degree of thermal stability, puncture resistance and conformability, such that the articles having the marker included therein may be subjected to repeated flexing and high temperature and humidity conditions such as encountered in commercial laundry operations without affecting the magnetic properties of the marker, while also not appreciably stiffening the article itself, thus being readily attached to or concealed therein.
Inventors
- 👤 Earl B. C/O Minnesota Mining And Hoekman
- 👤 Samuel C/O Minnesota Mining And Montean
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 19:04
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411; D; D06; D06H; D06H1/00; D06H1/04; G01; G01V; G01V15/00; G08B13/2428; G08B13/2437; G08B13/2442; G08B13/2445; G11; G11B; G11B33/00; G11B33/02; G11B33/04; G11B33/0405; G11B33/0488
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
169 words
A marker (10, 34) adapted for use in an electromagnetic article surveillance system wherein said marker generates a detectable signal related to an alternating electromagnetic field applied within an interrogation zone, said marker comprising an elongated section (12, 36) of a ferromagnetic amorphous metal having a ratio of length to square root of cross sectional area of at least 150, characterized by cover layers (14, 16 and 38, 40) of substantially continuous and flexible polymeric material in the range of 0.025 to 0.3 mm thick which seal all major surfaces of said metal section therebetween, said polymeric material exhibiting at temperatures up to 85°C a rate of water-vapor transmission and degrees of hydrolytic stability and puncture resistance sufficient to enable the marker to be subjected to at least fifty commercial laundrying cycles without appreciable change in those parameters, while also having a high degree of conformability so as to enable the marker to be affixed to or inserted in cloth or fabric articles without appreciable stiffening of the articles.
Claim 2
Dependent Claim
169 words
A marker (10, 34) adapted for use in an electromagnetic article surveillance system wherein said marker generates a detectable signal related to an alternating electromagnetic field applied within an interrogation zone, said marker comprising an elongated section (12, 36) of a ferromagnetic amorphous metal having a ratio of length to square root of cross sectional area of at least 150, characterized by cover layers (14, 16 and 38, 40) of substantially continuous and flexible polymeric material in the range of 0.025 to 0.3 mm thick which seal all major surfaces of said metal section therebetween, said polymeric material exhibiting at temperatures up to 85°C a rate of water-vapor transmission and degrees of hydrolytic stability and puncture resistance sufficient to enable the marker to be subjected to at least fifty commercial laundrying cycles without appreciable change in those parameters, while also having a high degree of conformability so as to enable the marker to be affixed to or inserted in cloth or fabric articles without appreciable stiffening of the articles.
Claim 3
Dependent Claim
46 words
A marker according to Claim 1, characterized by said metal section being formed with rounded ends (26), thereby avoiding the presence of sharp edges which tend to concentrate stress upon bending or flexing of the marker, thus causing the section to pierce the polymeric cover layers.
Claim 4
Dependent Claim
44 words
A marker according to Claim 1, characterized by said polymeric layers being formed with rounded ends (28), thereby avoiding the presence of sharp edges tending to protrude out of or from cloth or fabric articles within or upon which the marker may be affixed.
Claim 5
Dependent Claim
19 words
A marker according to Claim 1, further characterized by an adhesive layer (18) on at least one outer surface.
Claim 6
Dependent Claim
17 words
A marker according to Claim 4, characterized by said adhesive layer being either thermoplastic or pressure sensitive.
Claim 7
Dependent Claim
24 words
A marker according to Claim 1, characterized by said polymeric layers being adhesively or thermoplastically bonded together outside the edges of said metal strip.
Claim 8
Dependent Claim
17 words
A marker according to Claim l, characterized by said metal strip being totally sealed within said layers.
Claim 9
Dependent Claim
15 words
A marker according to Claim 1, characterized by said polymeric material comprising a polyester-urethane film.
Claim 10
Dependent Claim
51 words
A marker according to Claim 1, further characterized by at least one section of magnetizable material (42, 44, 46,'48, 50, 52, 54) which when magnetized biases said strip causing the signal produced thereby when in said interrogation zone to be detectably different than when said section is in an unmagnetized condition.
Claim 11
Dependent Claim
27 words
A marker according to claim 1, characterized by said metal section being. a strip having a thickness of less than 0.075 mm sealed between substantially planar covers.
Claim 12
Dependent Claim
13 words
A marker according to claim 1, characterized by an additional outer fabric layer.
References Cited (Backward Citations)
No citation records indexed.
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